Welcome to your go-to guide on slip ring induction motors, an essential component in various industries due to their unique features and performance characteristics. They are a subtype of induction motors, defined by the inclusion of slip rings—a crucial feature that significantly enhances their performance through additional control capabilities, especially during start-up and variable speed conditions.
A Detailed Exploration of Slip Ring Induction Motor Construction
Slip ring induction motors are engineered to address complex operational needs where control over starting conditions and speed variation is pivotal. These motors stand out due to their distinctive construction, characterized by the presence of sliding contacts known as slip rings, which differentiate them from their squirrel cage counterparts.
Breaking Down Construction Elements with a Diagram
To visualize the internal architecture of a slip ring induction motor, consider a diagram that slices the motor open, revealing its inner workings as follows:
- Stator: The stator is the stationary part of the motor, encased in a robust, typically cast-iron frame. It houses a set of electrical windings or coils that when energized, create a rotating magnetic field. These windings are distributed equally in slots along the inner periphery to ensure a uniform magnetic field.
- Rotor: At the heart of the motor is the rotor, which consists of a shaft and a cylindrical core with winding embedded along its length, resembling the stator’s structure. However, unlike the short-circuited windings in a squirrel cage rotor, this winding is brought out to the slip rings.
- Slip Rings and Brushes: Attached to the rotor’s shaft are the slip rings—typically made of conductive materials like copper or brass. Carbon brushes maintain electrical contact with the slip rings as they rotate, allowing the connection of resistors or other control devices in series with the rotor windings.
- External Resistance: The external resistance, connected through the brush and slip ring assembly, can be adjusted to control the motor’s performance. This adjustable resistance circuit is key to the unique capabilities of the slip ring motor.
Deciphering the Role of Each Component
The stator sets the motion in play with its electronically provoked magnetic field. The rotor, influenced by this magnetic environment, attempts to catch up with the speed of the magnetic field—a pursuit hindered intentionally by the insertion of resistance via the slip rings. By controlling this external resistance, one can influence the starting torque: decreasing resistance increases torque, providing the gentle startup and customizable speed necessary for certain applications.
The slip rings maintain a steady conductive path to the rotating rotor, allowing for continual adjustment of the motor’s behavior without the need for direct wiring that would tangle as the rotor turns. The brushes, although making contact with the slip rings, are designed to wear down and are therefore replaceable to ensure the long-term functionality of the motor.
In operation, adjusting the resistance can modulate several performance parameters of the motor. For example:
- At startup, increased resistance in the rotor circuit can lead to a higher starting torque, crucial for applications with heavy loads.
- During operation, adjusting resistance can help manage acceleration or deceleration, providing a granular level of speed control advantageous in precise applications such as textile processing or crane operations.
Understanding how these components depend on each other makes it clear why maintenance of slip rings and brushes is essential—they are the mainstays of the motor’s controllability. A well-maintained slip ring motor can thus provide reliable service in challenging industrial settings where standard motors might fall short.
Deciphering the Operational Principles of Slip Ring Induction Motors
Slip ring induction motors leverage the power of electromagnetic induction, much like other induction motors. However, they integrate an additional capability—controlling the rotor circuit’s resistance via slip ring, an enhancement that allows them to exhibit greater operational adaptability than typical induction motors.
Understanding the Working Principle
In a slip ring induction motor, the principle of operation is rooted in the formation and interaction of magnetic fields. As the stator windings are energized with an alternating current, they generate a rotating magnetic field. The strength and direction of this rotating magnetic field change in sync with the current’s phase changes. The rotor, placed in proximity to the stator, experiences this varying magnetic field.
The continually changing magnetic field induces a current in the rotor windings, owing to Faraday’s law of electromagnetic induction. The electrical energy generated within the rotor creates its magnetic field—a reaction field trying to catch up with the rotating magnetic field of the stator. But due to Lenz’s Law, which states that an induced current opposes the cause that produced it, the rotor always lags, creating a ‘slip’.
How Principles Enable Efficient Operation
Here’s where slip-ring technology steps in to demonstrate its significance. The rotor in a slip ring induction motor is not only driven by the induced current but, through the slip rings, also allows manipulation of the rotor circuit’s resistance. By changing the resistance—inserted into the rotor circuit via the slip rings—operators can influence vital motor characteristics.
- Controlled Starting Current: By increasing the resistance at startup, the motor can limit the starting current, preventing a sudden inrush that might overload the power supply or cause heating within the motor.
- High Starting Torque with Low Current: Increasing the slip—through added resistance—also augments the starting torque. As the rotor speed increases, the resistance can be gradually cut off, allowing the motor to accelerate smoothly to its full speed without compromising stability.
- Variable Speed Control: Adjusting the rotor resistance, hence the slip, also allows fine-tuning of the motor’s speed—an invaluable trait for applications demanding different operating speeds.
In effect, the operational principles of slip ring induction motors—electromagnetic induction with controllable rotor resistance—contribute to efficient performance, especially in challenging applications requiring high starting torque and variable speed control. Indeed, by accepting the ‘slip’ as an inherent feature and harnessing it through slip rings, these motors demonstrate a blend of power and sophistication.
From an operational perspective, understanding these powerful principles allows for optimal utilization and effective maintenance. Varying the resistance introduces different elements into the rotor circuit, enabling the dynamic, adaptable operation often required in industrial applications. This unrivaled versatility is a testament to the inherent efficiency of slip ring induction motors’ working principles.
Slip Ring Induction Motor Formula: Core of Motor Design and Performance
Electrical motors’ key operational parameters are governed by mathematical formulas, and the slip ring induction motor is no exception. The Eldring equation, a cornerstone to understanding and analyzing these motors, delivers critical insights into how changing variables impact motor performance.
Introduction to the Theoretical Framework
The Eldring equation for rotor current, represented as 𝐼r = 𝑈r / (𝑅r + 𝑠𝑋), provides an integral framework for understanding slip ring induction motor performance. In this equation:
- 𝐼r is the rotor current.
- 𝑈r is the rotor voltage.
- 𝑅r is the rotor resistance.
- 𝑠 is the slip.
- 𝑋 is the rotor reactance.
The rotor current is inversely proportional to the sum of the rotor resistance and the product of the slip and rotor reactance. At startup (when the slip, s=1), increasing rotor resistance via the slip rings decreases the rotor current and increases starting torque—a crucial performance aspect.
Translating the Formula to Real-World Scenarios
This formula underpins how a change in rotor resistance impacts the motor’s operational characteristics. To illustrate, consider a scenario where a slip ring induction motor faces a heavy load at startup:
- By manipulating the skirt part of the formula, 𝑅r + 𝑠𝑋, we can augment the starting conditions. At startup, slip (s) equals 1, and if we increase the rotor resistance (𝑅r), we decrease current (𝐼r) but enhance motor torque—a prerequisite for heavy startup loads.
- Conversely, during normal operation (s<1), reducing rotor resistance optimizes efficiency by maintaining a lower rotor current (𝐼r) without sacrificing the requisite torque.
Herein lies the elegance of the Eldering equation—it not only provides a theoretical framework for understanding the core principles of operation but also translates this understanding into hands-on motor control and design optimization.
** Building upon the Formula for Motor Performance and Design**
The Eldring formula holds a central place in comprehending the slip ring induction motor performance. It describes the relationship between several operational parameters opening up the path to optimize these variables tailored to specific requirements.
It is worth noting that this formula also underpins the design of slip ring induction motors:
- During the design phase, knowing the intended operational conditions (load type, required torque, etc.), engineers can apply the Eldring equation to decide the rotor resistance, reactance, and other properties to manufacture a motor that satisfies the required specifications.
- Post-production, engineers can again lean on the Eldring equation to devise optimal control strategies—modulating external resistance for desired current and torque based on real-time loads and performance needs.
Therefore, the Eldring equation is vital to both conceptualize performance characteristics and apply them practically—correctly predicting the interaction of different motor parameters with load conditions. Understanding and employing this formula can thus help operators harness the full potential of their slip ring induction machine, refining its efficiency, reliability, and longevity in various industrial settings.
Speed Control Landscape of Slip Ring Induction Motors
Slip ring induction motors are revered for their controllable operational dynamics, and mastering their speed is a testament to the sophistication they bring to motor technology. Various techniques harness the innate features of these motors to achieve precise speed regulation.
Exploring the Methods of Speed Control
The control of slip ring induction motor speed primarily revolves around the manipulation of slip—since the speed of the induction motor is directly determined by the slip relative to the synchronous speed of the rotating magnetic field produced by the stator. The following methods delineate the main approaches for managing motor speed:
- Rotor Resistance Control: By increasing resistance in the rotor circuit through the slip rings, the slip is increased, which effectively reduces the motor speed. This method is simple and provides a smooth control of acceleration and deceleration. However, it may lead to inefficiencies due to resistive losses.
- Varying the Stator Voltage: Changing the stator voltage influences the torque produced by the motor. A decrease in voltage reduces the torque and thus the speed, but this method is less effective as it gives a nonlinear torque-speed characteristic and can result in lower torque capabilities.
- Frequency Control with VFDs (Variable Frequency Drives): A highly efficient method for controlling the speed of slip ring induction motors is by varying the supply frequency using VFDs. By adjusting the frequency, the synchronous speed changes, which allows for a wide range of speed control with reduced power losses compared to rotor resistance control.
- Cascade Control: A more complex method involves connecting two motors in a cascade configuration. Here, the slip power of the first motor (controlled motor) is used to drive the second motor (secondary motor). By doing so, a range of stable operating speeds can be achieved. This method is particularly useful for applications that need a broad range of speed control.
Understanding Impact on Efficiency and Application
Speed control mechanisms within slip ring induction motors are not merely about achieving the desired speed but also play a crucial role in optimizing the motor’s efficiency and matching the motor’s application-specific requirements.
- Efficiency Considerations: Rotor resistance control, while versatile and simple, can dissipate a considerable amount of energy in the form of heat due to added resistive components. This is where the use of VFDs shines, as they control speed more efficiently without significant energy loss. Variable frequency drives adjust the motor’s electrical input, preserving the motor’s efficiency across varied loads and speeds.
- Application Suitability: The chosen method for speed control must align with the application’s demands. For instance, applications that require high torque at low speeds may benefit from rotor resistance control. In contrast, applications that need energy-efficient speed control over a wide range of speeds, like conveyors or pumps, favor the use of VFDs.
Each technique reflects a compromise between precision, efficiency, complexity, and cost. As the industry needs to evolve and demand more versatile and energy-efficient solutions, the integration of advanced controls, such as VFDs, is becoming increasingly prominent. Mastery over slip ring induction motor speed not only embodies an understanding of these control methods but also the expertise to deploy them effectively—tailoring operations to the intricate dance of industry requirements and technological possibilities.
The Heart of Slip Ring Induction Motors
In the realm of induction motors, a key component sets apart certain models and lends them their specific name—slip rings. These motor parts may seem modest in size, but their operational and design aspects wield a profound influence on the motor’s performance and flexibility.
Understanding the Function of the Slip Ring
The raison d’être of the slip ring is to transfer an electrical signal or power from a stationary system (the stator) to a rotating part (the rotor). Pivotal to the motor’s operation, this mechanism involves:
- In a slip ring induction motor, three slip rings are mounted on the rotor’s shaft.
- The motor’s rotor windings’ end connections are brought out and connected to these slip rings.
- Carbon-brush contacts, stationary and connected to the motor’s external circuit, slide on the slip rings as the rotor starts rotating.
- Through this physical connection, the slip rings enable the transfer of electricity to the rotor circuit, even during rotation.
But there’s more to this dynamic than just electrical transmission. By adding external resistance via this slip rings at startup, the motor can control the starting current and enhance torque—an essential function that distinguishes slip ring induction motors from their squirrel cage counterparts.
Venturing into Design and Material Considerations
Designing and constructing slip rings call for thorough deliberation as these components must withstand continuous use, voltage surges, and temperature fluctuations while maintaining reliable electrical contact.
- Materials: The predominant material used in slip rings is copper or a copper alloy. This choice is due to copper’s excellent electrical conductivity. However, the surface of the copper slip rings is typically plated with a noble metal (like silver, gold, or rhodium) to reduce wear and improve surface quality.
- Design: The slip rings’ size and number are typically determined by the power to be transmitted and the motor’s overall dimensions. Their positioning, mechanical strength, and compatibility with brush materials must also be considered to ensure efficient operation. For the brushes, graphite or metal graphite composites are commonly used, offering a balance of good electrical contact and minimal wear on the slip rings.
Both the material and design considerations attest to the demand for robustness, reliability, and electrical efficiency. By balancing these factors, slip rings not only fulfill their role but also underpin the broader capabilities and performance of slip ring induction motors.
Conclusively, the slip rings act as a dynamic bridge between static and rotating motor parts, enabling functionalities that broaden the range of applications for slip ring induction motors. So, while being humble in size, they exhibit an importance that is anything but—indeed, they form the very heart of a slip ring induction motor. Understanding their role, design, and material considerations illuminates the intricate and carefully deliberated operations that go into every motor run cycle.
Deciphering Excellence in Slip Ring Induction Motor Manufacturing
When it comes to incorporating slip ring induction motors into industrial applications, selecting a motor from a reputable manufacturer is paramount. The difference between manufacturers often lies in their innovation, quality, and reliability—all of which directly influence the motor’s performance and longevity.
Review of Standout Manufacturers
While the global market is dotted with numerous entities, a few have risen through the ranks by establishing themselves as paragons of slip ring induction motor production. These top manufacturers are distinguishable by their:
- Innovation: Leaders in the field typically invest heavily in Research & Development (R&D) to refine motor efficiency, and power density, and tailor solutions to niche applications. They pave the way with advanced design features like improved cooling systems, the use of durable materials, and the integration of smart sensors that monitor motor performance.
- Customization: Premier manufacturers offer custom-designed motors that are specifically engineered to operate under the unique demands of intricate applications. Whether to conform to specific torque-speed characteristics, fit into limited spaces, or handle harsh environmental conditions, their ability to customize motors adds significant value.
- Quality and Durability: Their products consistently meet high-quality standards ensured by rigorous testing protocols, from raw materials inspection to finished product endurance tests. Moreover, these manufacturers often provide more durable components that can withstand the rigors of continuous industrial operation.
Criteria for the Ideal Motor Supplier
The selection of a suitable slip ring induction motor supplier hinges on several critical factors that align with application-specific requirements:
- Technical Specifications Compatibility: The motor should meet the precise electrical and mechanical requirements of the application, including power rating, voltage, slip range, and starting torque.
- Application Environment: Suppliers should be chosen based on their experience in building motors for similar industrial environments. Motors operating in extreme temperatures, dusty or wet conditions, hazardous locations, or under fluctuating load conditions demand suppliers with specialized knowledge and proven solutions.
- After-Sales Support: Reliable after-sales support is crucial. Look for suppliers who provide comprehensive maintenance services, ready availability of spare parts, and prompt technical support to mitigate downtime risks.
- Regulatory Compliance: It’s essential to select a supplier whose products are compliant with national and international regulatory standards, ensuring safe operation and the possibility of integration in markets worldwide.
- Cost vs. Performance Balance: While initial cost is a factor, it should be weighed against long-term benefits like energy efficiency, reduced maintenance, and the motor’s lifespan. A supplier that offers a well-balanced cost-performance ratio can contribute significantly to operational cost savings.
Choosing the right slip ring induction motor manufacturer is not an exercise in selecting a generic product off the shelf—it’s about finding a partner that can deliver a motor solution attuned to the symphony of specific industrial demands, with the durability to endure and the resourcefulness to support. As such, the decision process is both an exacting technical evaluation and a strategic business consideration.
Balance of Merits and Concerns: Evaluating Slip Ring Induction Motors
Striking a balance between motor requirements and available motor technologies is central to efficient and cost-effective industrial operations. Among the numerous contenders, slip ring induction motors uphold a unique repertoire of advantages, albeit accompanied by certain drawbacks. Here, we provide an objective appraisal of these motors—guiding you to a holistic understanding of when these motors are the best choice.
Assessment of Pros and Cons
Like all technologies, slip ring induction motors present a range of pros and cons that inherently influence their suitability for various applications:
- Controlled Startup: Equipped with external rotor resistance, they offer a high starting torque with a low starting current—a significant advantage for applications that require high torque at startup.
- Speed Regulation: Slip ring motors afford the user granular control of speed using rotor resistance, which can be crucial for applications demanding varying speeds.
- Load Fluctuation Resistance: These motors showcase resilience against load fluctuations, and they can operate at elevated slips without overheating.
- Maintenance: Due to the presence of slip rings and brushes that require periodic maintenance and replacement, these are high-maintenance motors compared to others like squirrel cage induction motors.
- Size and Cost: Due to the additional components (slip rings and brushes), slip ring motors are typically larger and more expensive than comparable squirrel cage motors.
- Efficiency Concerns: Rotor resistance control, while affording speed control, can lead to power dissipation as heat, affecting energy efficiency.
Comparison with Other Motor Types
Given this balance of benefits and drawbacks, slip ring induction motors emerge as suitable candidates compared to other motor types in certain scenarios:
- Start-Up Conditions: With their high starting torque and reduced starting current, these motors excel over squirrel cage induction motors in applications needing a ‘powerful push’ at the start (e.g., heavy machinery, crushers, or lift elevators).
- Speed Variation: When there’s a need for effective speed regulation under varying load conditions (like in certain types of compressors and mills), slip ring motors outshine fixed-speed counterparts like split-phase or capacitor start motors.
- Limitations of Other Motor Types: In instances where a direct online (DOL) start would lead to a current overshoot, or where a variable frequency drive (VFD) would be too costly, a slip ring induction motor presents an attractive alternative.
In conclusion, the efficacy of slip ring induction motors is a matter of purpose and context rather than an absolute metric. The astute engineer must weigh up the advantages and disadvantages, delving beyond mere technical specifications to consider issues of maintenance, cost, size, and efficiency when deciding on the choice of motor. The case for the slip ring induction motor is a testament to the art of discerning wisdom in technological trade-offs—an ability that illuminates the pathway toward optimally configured industrial systems.
The Slip Ring Induction Motor Across the Application Spectrum
The versatility of slip ring induction motors plays out in their ability to serve a variety of industrial and commercial applications. This adaptability, stemming from their unique features like high starting torque and finely adjustable speed, makes them go-to solutions in specific operational contexts. Let’s delve into an overview of these applications and illustrate some real-world examples of this motor’s aptness.
Industrial and Commercial Applications
Slip ring induction motors have found their niche in a range of areas:
- Pumps & Compressors: In water treatment facilities and oil refineries, these motors drive large pumps and compressors, thanks to their ability to handle variations in load and provide superior speed control.
- Conveyor Systems: In industries like mining and heavy manufacturing, their high starting torque proves advantageous in running heavy-duty conveyor belts.
- Crushers and Mills: Applications involving significant moment of inertia at start-up, like crushers and mills, make good use of the slip ring motors’ capacity to deliver high starting torque without drawing a high starting current.
- Elevators: They’re preferred in high-capacity elevators employed in commercial buildings and industries where load fluctuates noticeably.
- Wind Turbines: High-capacity wind turbines use these motors for their controlled start-up and ability to handle variations in wind speed.
Case Studies Illustrating Optimal Use
It’s through real-world examples that the advantages of slip ring induction motors truly take center stage:
- Mining Operations: Consider a heavy-load rock crusher used in mining. These machines require a substantial force to break down large rocks into manageable sizes. To procure this force, high torque is necessary during start-up—an arena where slip ring induction motors excel.
- Wind Energy Generation: In the case of a wind turbine, wind speed and, therefore, the electrical generation load can vary significantly. Here, the slip ring induction motor’s capacity to cope with load variations and provide proportional speed control proves optimal. Using rotor resistance, the generator can adapt to fluctuating wind speeds, which stabilizes power generation.
In such instances, the broad adaptability of slip ring induction motors cuts across diverse industrial terrains. This ability to conform to dynamic operational needs, whether it’s a high starting torque or adept speed variation, places them in an indispensable position in many technological realms—an everyday testament to their engineering brilliance. The judicious application of these motors, informed by realistic expectations and an understanding of their natural habitat, paves the way for optimal industrial and commercial operations.
By understanding the intricacies that surround slip ring induction motors, we can appreciate their unique value proposition in diverse industries. Despite their challenges, these motors continue to hold their ground, delivering unparalleled control benefits in several applications. Looking forward, advancements in design and technology may further enhance their performance efficiencies, making them an asset worth understanding and considering in any electric motor discourse.


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The GPL Presents: “What’s Wrong With My HousePlant?”
About This Event
Join the Greenfield Public Library, in collaboration with the Tewksbury Public Library, for the virtual program What’s Wrong With My House Plant?, on Thursday May 4, at 2 pm.
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For more information and to register for the talk, go to https://us02web.zoom.us/webinar/register/3016794309644/WN_FqTxyrBCTSa_RLSedRdqog
***Please note: This program will NOT be recorded.
This program, sponsored by the Tewksbury Cultural Council, the Friends of the Tewksbury Public Library, and the Friends of the Greenfield Public Library, is free and open to the public.

domain: library


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domain: geography


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Treatment of all in-contact pets Most flea shampoos contain pyrethrins or organophosphates and do a good job of getting rid of louse infestations. Topical insecticides like imidacloprid (Advantage) applied topically every 2 weeks will also kill lice.
Also, Do You Know Does flea and tick spray kill lice?
PESTICIDE SPRAYS DO LITTLE OR NOTHING TO CONTROL LICE. NEVER treat your home, car, furni- ture, beds, pillows, or clothing with pesticides (e.g. ‘lice bombs,’ flea bombs, sprays, etc.) in an attempt to control head lice. You will expose yourself and your family to unnecessary pesticide risk.
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Similarly, Best Dog Flea and Tick Shampoo – Flea Shampoo for Cats
Frequently Asked Questions(FAQ)
Can flea shampoo be used on human hair?
Can you use dog/cat flea shampoos on humans? Another possible treatment for fleas in human hair is using dog or cat flea shampoo. According to some opinions, this should be fine. However, pet flea shampoo might contain chemicals or pesticides that can be dangerous for humans.
What is the fastest way to get rid of dog lice?
Insecticide shampoos and lime-sulfur dips are generally considered safe and effective for the removal of lice on dogs. They should generally be used weekly for a period of four to six weeks. Comb through the fur with a lice comb after each treatment can remove dead lice from the fur.
Can you use flea treatment for nits?
One study providing preliminary data found that a concentration of 0.2 % on an adult was effective and safe. However, Animal Products (e.g Advantage Flea Treatment) contain about 10 % imidacloprid, a 50 x greater dose. Lindane is a toxic pesticide which was once used in New Zealand to treat head lice.
Does Dawn dish soap kill lice?
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Pediculicides, particularly ivermectin lotion, are the strongest measures to get rid of a lice infestation. Pediculicides or medications that kill lice are the strongest measures to get rid of a lice infestation.
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Getting rid of head lice Unfortunately, even a shampoo as effective as Head & Shoulders won’t help when it comes to head lice.
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You shouldn’t use dog shampoo to treat lice on humans. It’s true that it may contain some of the same active ingredients as some anti-lice shampoos. However, dog shampoo is not made for and has not been tested on humans.
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What are fleas? Fleas, like lice, are small wingless insects. Unlike lice, which can only crawl, fleas can jump from one host (such as a pet) to another. Fleas mainly feed on non-human hosts but are able to infest humans.
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Comb the hair (using a fine toothed comb) thoroughly to remove dead fleas and eggs. Tea tree oil based shampoos are also very effective for killing fleas in hair. The oil is anti-parasitic and anti-microbial in nature which can kill fleas and their eggs.
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Dog lice hook onto dog hair and are difficult to dislodge. Infestations move from one animal to another and from contaminated bedding and grooming tools. Before using any treatments, ask your veterinarian to tell you what product is safest for your dog.

domain: pet


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Zero-G has released Ecstatic Grooves, a collection of sample accurate drum and percussion loops, hand crafted drums and fx, all sculpted from the ground up to satisfy the needs of the most demanding DJs and dance producers and ready to drop into your tracks with the minimum of trouble and the maximum of impact.
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- Kontakt2 Instruments
- Reason Refill
- 1650 Rex2 Files (Stylus Compatible)
- 2200 Acidized Wav Files
- 2200 Aiff Apple loop Files
For full product info including demo songs and PDF of the full contents list, visit the Ecstatic Grooves web page on the Zero-G website.
Ecstatic Grooves has a recommended retail price of $109.95 / €90 / £59.95.

domain: artistic


text:
I guess since this is the series finale, things were going to get all patched up. But wasn't it too happy? Bonnie gets buried, Beck figures out that the government is corrupt, the Rangers are off the hook, they get the bomb to Texas, Hawkins lives, and Stanley and Mimi get married. I thought it was a little out of character for the show to work out. But this being the finale, maybe it's understandable.
Don't get me wrong, I liked the finale. Hawkins and Jake's trip to get the bomb was the most, and maybe only, exciting part. I loved the parts with Jake in the plane. I guess it was lucky he knew how to operate that thing. Right? I like how Beck finally came to his senses. It was a nice little surprise for his men to see the truth too. I also like Johnston's flag being put up. It was like he was part of the episode. The only ones who were missing were Darcy and the kids. I know that they added no benefit to the story, but his being the finale and all, they should just be there.
So long, Jericho, you will be missed. There are many shows that have long overdue series finales, but you weren't one of them. But sometimes even the most beloved shows end. Like Hawkins said, you made history; maybe not as a long-lasting award-winning series you could have been but as the one with the biggest fanbase.

domain: entertainment


text:
[Dixielandjazz] New Keyboard
steveheist35 at gmail.com
Mon Dec 15 07:09:52 PST 2014
An inflatable piano - gosh, that would be like sleeping on an air mattress
and just as bad LOL
I found an excellent piano called a Williams Allegro piano - bought it from
Guitar Center for $200!!!
Weighs 40 lbs., 88 key, weighted, has voices but I use it as a controller...
I love the feel of it and you can't beat the price!!!
Steve "Stubby" Heist
From: Andy Ling
Sent: Monday, December 15, 2014 6:55 AM
To: Steve Heist
Cc: Dixieland Jazz Mailing List
Subject: Re: [Dixielandjazz] New Keyboard
> Bob wrote:
> >A few pumps on the tire pump and I have a full 88 keyboard that plays
> sounds like a Bösendorfer.
> It sounds so plausable. I'm not sure yet if Bob is pulling our collective
I guess it must be one of these
To unsubscribe or change your e-mail preferences for the Dixieland Jazz
Mailing list, or to find the online archives, please visit:
Dixielandjazz mailing list
Dixielandjazz at ml.islandnet.com
More information about the Dixielandjazz

domain: hobby


|Publication number||US7591307 B2|
|Application number||US 11/518,392|
|Publication date||Sep 22, 2009|
|Filing date||Sep 7, 2006|
|Priority date||Sep 7, 2006|
|Also published as||CA2662762A1, CA2662762C, CN101517191A, CN101517191B, US20080060808, WO2008030620A1|
|Publication number||11518392, 518392, US 7591307 B2, US 7591307B2, US-B2-7591307, US7591307 B2, US7591307B2|
|Inventors||James Garland Gibson|
|Original Assignee||Sondex Ltd|
|Export Citation||BiBTeX, EndNote, RefMan|
|Patent Citations (38), Non-Patent Citations (2), Referenced by (2), Classifications (12), Legal Events (4)|
|External Links: USPTO, USPTO Assignment, Espacenet|
The invention relates to a method of and system for determining the free point in a drill pipe.
Drill pipes are used in the extraction of natural resources such as oil, water, gas and other hydrocarbons from underground deposits. In a drilling operation, a rotating drill bit is used to create a bore hole or well extending from the surface, through intervening layers of earth or rock, to a deposit. A metal drill pipe is used to line the bore hole and is added in sections as the drilling progresses. Individual sections of the drill pipe may be secured to each other by screwing together threaded connector portions. The threaded sections are generally referred to as collars, as the external diameter may be locally increased.
The drill pipe sections are inserted into the bore hole from the surface. However, as they are lowered into the bore hole, it is possible that one or more of the sections will become wedged in a restriction in the earth or rock formation. The location in the bore hole where this occurs is called the stuck point. The section immediately above the stuck point is referred to as the ‘free point’.
The section of drill pipe that has become stuck is a problem, as it means that further drilling cannot continue. In such circumstances it is common practice to ‘back off’ and recover as much of the drill pipe and equipment as possible for later use, possibly abandoning the drill pipe below the stuck point and redrilling in a different direction from a higher point in the bore hole. This will require that the threaded collar immediately above the stuck point is identified, and that explosive charges are detonated to loosen the threads while reverse torque is applied. It is therefore desirable to determine the exact location of the stuck point.
A number of devices are known for this purpose, and will now be described by way of introduction. All such devices rely on the fact that torque or stretch, applied at the surface will be transmitted to all sections of the drill pipe above the stuck point, but to none below the stuck point.
U.S. Pat. No. 2,902,640 describes a device for determining whether a thread is responding to reverse torque, and illustrates the general principle. A device having an inductor, or sensor coil, and at least one bar magnet coaxially aligned with the sensor coil is paid out into the drill pipe. The ends of the coil are attached to a galvanometer at the surface so that any change in the magnetic field provided by the magnet will result in a change in the magnetic flux threading the coil and a detectable change in current measured by the galvanometer. The lines of magnetic flux generally flow though the metallic casing of the drill pipe. Thus, while ever the device moves though the drill pipe in locations away from a threaded section, the magnetic flux will stay constant, as the diameter and construction of the drill pipe section will not vary significantly. Where a threaded section occurs however, the lines of magnetic flux encounter the threading collar. The different diameter and construction of the drill pipe collar cause a resulting change in the lines of magnetic flux, as the coil moves relative to the collar. This change in the magnetic field causes an induced current to flow in the sensor coil which can be detected at the surface to indicate that the device is located at a threaded connector portion. The device is then held in position, while a torque is applied at the surface. If the threaded connector portion is free to move, the resulting motion of the threads of the two drill pipe sections will cause a further disruption in the magnetic field with a corresponding induced current being generated in the sensor coil. By detecting this second current signal, coincident with the application of the torque, the threaded section can be determined as being free to move. However, if the threaded sections are jammed then the application of the torque will not cause any motion, and no current signal will be detected coincident with the application of the torque. This method suffers from the fact that the threads at the selected collar may well be firmly locked, while threads higher up may be less tight, and hence undo themselves before the test can be made.
U.S. Pat. No. 3,004,427 shows a more complicated device that works on similar principles. The device has two connected axially rotatable sections, each carrying one of two co-operating cores. The cores are located adjacent each other and mounted for independent rotational movement. The relative position of the co-operating cores with respect to each other is initially set by applying a direct current to a coil located on one of the cores. In doing so, that core becomes magnetised and attracts the other into a start position. If the upper section of the device is located in part of the drill pipe that is free to move, and the lower device section is located in a part that is stuck, then a torque applied to the drill pipe will cause the upper section of the device to rotate away from the lower section. The two cores also therefore rotate away from each other causing an air gap in the magnetic circuit, and hence a significant change in the self inductance of the sensor coil, which is excited with an AC voltage during the test. If the two sections of the device are both located in a stuck section of the drill pipe, then there is no relative motion of the two cores and no change is detected.
Both of these devices require stationary measurements to be made at a series of individual locations in the bore hole, so that location of the stuck point is a laborious and iterative process.
Another device with a different mode of operation is also known from U.S. Pat. No. 4,440,019. The device writes magnetic spots or marks along the length of the wall of the drill pipe by discharging a surface capacitor bank through a sensor coil. The effect is similar to the writing of a signal onto magnetic tape. Once the marks have been made, the device is recovered and lowered once again into the drill pipe, while the location of the magnetic spots is logged using the sensor coil. The movement of the sensor coil past the magnetic mark causes an induced voltage in the sensor coil, indicating the position of the mark for a sensor log. A twisting or longitudinal force is then applied to the drill string causing stress in the string. The induced strain has been found to substantially erase all of the magnetic spots above the stuck point. The device is then reinserted into the bore hole to measure the location of the magnetic marks once again. As all of the spots above the stuck point will have been erased, the location of the stuck point can be deduced from comparison of the logs before and after the drill pipe was flexed, and in particular from the position of the highest remaining magnetic mark in the second log.
This device suffers from a number of problems. First, it is necessary to rig up and lower a fishing tool to retrieve the expensive measurement equipment from the vicinity of the drill bit. Then, it is necessary to rig up and lower, often on a different cable, the device to make two or three excursions into the drill pipe, first to write the magnetic marks, and subsequently to read them before and after the tension is applied. Also, the strength of the magnetic mark that is detected depends on the speed at which the detector coil passes through the magnetic field in the pipe. In order to produce a good signal and a reliable log, it is therefore necessary to move the sensor coil at substantially the same speed while the logs are being produced. The coil sensitivity is in practice also limited.
The running costs of a drilling rig dictates that a drilling company locate the position of a stuck point with minimum delay. In view of the above problems, we have therefore appreciated that there is a need for an improved method of determining the stuck point, and an improved system for use with the method, that saves time and is more sensitive.
The invention is defined in the independent claims to which reference should now be made. Advantageous features of the invention are set out in the dependent claims.
Preferred embodiments of the invention will now be described by way of example with reference to the drawings, in which:
A preferred embodiment of the invention will now be described with reference to
The down hole device 2 is located within the drill pipe or casing 3 within the bore hole. At the bottom end of the drill pipe is a drill bit 10 mounted on one or more heavy drill collars 11. The drill bit and collar, and the drill pipe, form what is known as a drill string. In
An MWD sensor is a device for taking periodic measurements of the down hole conditions in the bore hole and transmitting the resulting data to the surface for confirming the direction of drilling and other analysis. The sensor data will often be transmitted to the surface via a mud pulse, created by a mud pulser apparatus in the vicinity of the sensor. The pulse then propagates upwards in the bore hole to the surface recording device 7. The measurements may also be stored in memory in the MWD sensor and retrieved when the sensor is recovered from the well. Typically, an MWD sensor will include a sensitive magnetic field sensor 21 and associated control circuitry for detecting the magnetic field strength in the bore hole in three dimensions. In doing so, the orientation of the drill bit relative to the magnetic field of the earth can be determined. The MWD device of the preferred embodiment however comprises modified control circuitry for operating the sensor. This will now be described in more detail with reference to
Sensor 21 is a three dimensional magnetic field sensor. These typically comprise three individual sensors, each orientated with respect to the others to detect the magnetic field strength in a respective one of the x, y and z directions. Various types of magnetic field sensor could however be used, such as sensitive flux-gates, magnetoresistive devices, Hall Effect devices, or any static sensing directional magnetometer.
Sensor 21 is connected to control unit 22, and to memory unit 23. The control unit 22 is further connected to the memory unit 23, and to transmitter device 24 and receiver device 25. According to the preferred embodiment of the invention, the control unit and sensor have two distinct modes of operation. The first mode provides an indication of the underground orientation of the drill string with respect to the magnetic field in known fashion. In this mode, the control unit 22 is arranged to take periodic measurements via the sensor and operate the transmitter device 24, typically a mud pulser, such that the measurements are transmitted to the surface. The second mode is activated only when the drill bit or drill pipe has become stuck, and the MWD sensor is to be retrieved from the bore-hole. As explained above, it will be appreciated that although a drill bit that has become stuck may be abandoned it is desirable to recover as much of the expensive equipment used in the bore-hole as possible.
In the second mode, the magnetic sensor is configured to detect the stuck point of the drill pipe as will be explained below. In this mode, the control unit also takes measurements of the magnetic field, and stores these in memory 23 or transmits them to the surface. Preferably, the control unit is instructed to switch from the first mode of operation to the second mode of operation via a control signal received at receiver 25. This may be a mud pulse or other telemetry signal, or a command from the fishing tool via magnetic or electrical coupling.
In the first mode of operation, the control unit takes readings from the sensor at a rate reflecting the drilling tool's slow movement through the underground rock or earth formations. On switching to the second mode however, now made available by the preferred embodiment of the invention, the control unit 22 increases the rate at which readings from the sensor are taken, so as to correspond to the MWD sensor's much faster ascent in the bore hole when it is being retrieved. In the first mode, the sensors are read every 10 to 20 seconds, commensurate with the drill penetration rate through the rock or earth formation, in order to achieve 1 or 2 samples per foot of distance. During retrieval of the MWD sensor, the speed is 1500 to 3000 feet/hour, and the marks are ideally read at 0.5 inch intervals. The sampling rate in the second mode is therefore around 10 to 20 samples per second. In the preferred embodiment, the frequency of the first and second modes can therefore be seen to differ by around a factor of 100.
Referring again to
Control apparatus 6 may comprise a computer program arranged to control the operation of the down hole device 2, such as the MWD sensor, as well as or separately to the fishing tool 16. This or another computer program may be provided to operate on the data obtained from the magnetic field sensor in order to provide one or more traces indicating the position of the magnetic marks in the bore hole. This computer program may be provided at the surface or within either the down hole device 2 or fishing tool 16.
A preferred method for detecting the stuck point using the apparatus described above will now be described. With reference to
First, the fishing tool with the device 19 for writing magnetic marks is lowered into the bore-hole on the wireline. By means of the surface control systems, current is pulsed into the coil of the fishing tool at regular intervals so as to leave detectable magnetic marks in the metal drill pipe. The fishing tool is lowered into the borehole until the fishing grapple 18 contacts and engages with the connector 13 of the MWD sensor.
A control signal is sent to the MWD sensor to switch the device from the first sensing mode to the second sensing mode. As explained above, the length of time between readings is preferably smaller in the second mode than in the first, because the MWD sensor will move more quickly during the retrieval process, than when its motion is from the drilling action of the drill string. The switching command signal may be transmitted from the surface to the MWD device via mud pulse, or other means. In alternative embodiments, the command signal may be transmitted to the MWD sensor via the fishing tool. For example, once the two devices are connected, a signal may be transmitted by a direct electrical connection, such as a plug/socket connection, or indirectly via inductive or short-hop telemetry coupling.
Once the MWD device is operating in the second sensing mode, it is drawn upwards in the borehole by the fishing tool and the action of the wireline. The control unit takes readings from the magnetic field sensor and either stores these in memory or transmits them to the surface via the retrieval tool. A log of the positions of the magnetic marks in the borehole is produced. If the log is stored in memory, it may be recovered once the MWD device reaches the surface and is extracted from the borehole.
Once the MWD sensor has reached the top of the well, or thereabouts, a torque or pull is applied to the top of the drill pipe to erase or diminish the magnetic marks above the stuck point. The assembly of fishing tool and MWD sensor is then lowered into the borehole and retrieved once again. As before, the control unit takes readings from the magnetic field sensor as the MWD device is raised in the borehole and a log of positions of the magnetic marks in the borehole is produced. As is known in the art, comparison of the two records will then reveal that the marks above the stuck point, which have become stressed, have become weaker, allowing the precise location of the stuck point to be determined.
The use of a three dimensional magnetic field sensor means that a comparison can be made of the different directional field components of the magnetic marks, allowing greater detection sensitivity. The data obtained from the magnetic field sensors is therefore preferably input into one or more algorithms in order to give a number of different outputs or traces. Any or all of the algorithms may be employed to provide multiple log traces thus maximising the visibility of the stuck point when the two log passes are compared. Alternatively, the choice of algorithm may depend on the geometry of flux pattern created by the marking coil and the particular pole piece arrangements. Remembering that the three sensors are configured to give x, y and z signals (the z axis is in the longitudinal direction of the borehole, while the x and y axes are orthogonal) suitable choices of algorithm from which logs may be derived are:
All of these algorithms provide a log signal which is insensitive to the rotational orientation of the tool along the axis of the borehole. This is important to achieve log consistency, as the sensors are likely to rotate around the longitudinal axis of the borehole during the logging process. Logs could be derived from one or more of the above, alone or in combination.
The technique described above allows the retrieval of the down hole equipment and the determination of the free point to be determined from only two excursions into the bore hole. This is in comparison with the three excursions necessary to retrieve the MWD and determine the stuck point in the prior art. A drilling company can therefore save considerable time and expense.
Additionally, as the sensing of the magnetic marks is achieved using the sensors of the MWD, the speed at which the MWD sensor is moved through the drill pipe does not affect the magnitude of the mark detected. Where a coil is used both to write the marks and detect them, the detected strength of the mark is dependent on the rate of change of the magnetic field not the actual strength of the mark itself.
A number of alternative methods and apparatus for determining the stuck point are also contemplated. For example, in an alternative embodiment the data obtained by the MWD sensor may be stored in the fishing tool, and/or transmitted to the surface by the wireline connection 8. Additionally, the fishing tool itself may be provided with a three dimensional magnetic field sensor to detect the magnetic marks made by the coil. In this way, the fishing tool both writes and reads the marks, and an MWD sensor supporting the two modes of operation described above is unnecessary. In a further alternative embodiment, the three dimensional sensor may be incorporated into the stuck point sensor of the prior art. Although, this would not allow the advantageous method described above, it would allow the magnetic marks to be detected with greater accuracy, and without any distorting effects resulting from the speed at which the device is moved.
|Cited Patent||Filing date||Publication date||Applicant||Title|
|US2902640||Dec 15, 1954||Sep 1, 1959||Foster Jack E||Detection of stuck point in wells|
|US3004427||Apr 29, 1957||Oct 17, 1961||Dia Log Tubular Survey Company||Free point indicator for determining the point at which stuck pipe is free in a well|
|US4440019||May 28, 1982||Apr 3, 1984||Marshall W Ray||Free point indicator|
|US4444050||Nov 18, 1981||Apr 24, 1984||Halliburton Company||Freepoint indicator|
|US4675029||Nov 21, 1984||Jun 23, 1987||Geoenergy International, Corp.||Apparatus and method for treating the emission products of a wood burning stove|
|US4766764 *||Feb 25, 1987||Aug 30, 1988||Halliburton Company||Magnetic freepoint sensor utilizing spaced hall effect devices|
|US5479989||Jul 12, 1994||Jan 2, 1996||Halliburton Company||Sleeve valve flow control device with locator shifter|
|US5564502||Jan 30, 1995||Oct 15, 1996||Halliburton Company||Well completion system with flapper control valve|
|US5622223||Sep 1, 1995||Apr 22, 1997||Haliburton Company||Apparatus and method for retrieving formation fluid samples utilizing differential pressure measurements|
|US5741962||Apr 5, 1996||Apr 21, 1998||Halliburton Energy Services, Inc.||Apparatus and method for analyzing a retrieving formation fluid utilizing acoustic measurements|
|US5758724||Jan 6, 1997||Jun 2, 1998||Enlink Geoenergy Services, Inc.||Underground heat exchange system|
|US6065540 *||Feb 8, 1999||May 23, 2000||Schlumberger Technology Corporation||Composite coiled tubing apparatus and methods|
|US6250371||Dec 12, 1999||Jun 26, 2001||Enlink Geoenergy Services, Inc.||Energy transfer systems|
|US6594394||Jul 22, 1999||Jul 15, 2003||Geoenergy, Inc.||Fast compression and transmission of seismic data|
|US6672371||Jan 26, 1999||Jan 6, 2004||Enlink Geoenergy Services, Inc.||Earth heat exchange system|
|US6694766||Aug 21, 2002||Feb 24, 2004||Enlink Geoenergy Services, Inc.||Power generation systems with earth heat transfer|
|US6955219||Jul 3, 2003||Oct 18, 2005||Enlink Geoenergy Services, Inc.||Earth loop installation with sonic drilling|
|US7093657||Oct 10, 2005||Aug 22, 2006||Enlink Geoenergy Services, Inc.||Earth loop installed with sonic apparatus|
|US7270182||Aug 18, 2006||Sep 18, 2007||Enlink Geoenergy Services, Inc.||Earth loop installed with sonic apparatus|
|US20020070017||Dec 7, 2000||Jun 13, 2002||Soliman Mohamed Y.||Method and apparatus for treating a wellbore with vibratory waves to remove particles therefrom|
|US20020104643||Aug 15, 2001||Aug 8, 2002||Amerman Thomas R.||Energy systems|
|US20040031585||Jul 17, 2003||Feb 19, 2004||Johnson Howard E.||Earth loop energy systems|
|US20040194914||Jan 5, 2004||Oct 7, 2004||Johnson Howard E.||Bottom member and heat loops|
|US20050240351||Oct 18, 2004||Oct 27, 2005||Weatherford/Lamb, Inc.||Method for determining a stuck point for pipe, and free point logging tool|
|US20050269081||Jun 8, 2004||Dec 8, 2005||Rose Lawrence C||Positive engagement indicator for wireline fishing operations|
|US20060122780||Nov 10, 2003||Jun 8, 2006||Geoenergy, Inc||Method and apparatus for seismic feature extraction|
|US20070012446||Aug 18, 2006||Jan 18, 2007||Johnson Howard E Jr||Earth loop installed with sonic apparatus|
|US20080042870 *||Aug 15, 2007||Feb 21, 2008||Schlumberger Technology Corporation||Method of determination of a stuck point in drill pipes by measuring the magnetic permeability of pipes|
|EP0196829A2||Mar 20, 1986||Oct 8, 1986||Halliburton Company||Well tool|
|EP0692610A2||Jul 11, 1995||Jan 17, 1996||Halliburton Company||Downhole sleeve valve and stimulation tool|
|EP1644671A1||Jun 14, 2004||Apr 12, 2006||Enlink Geoenergy Services, Inc.||A method of constructing a geothermal heat exchanger|
|EP1647669A1||Oct 12, 2005||Apr 19, 2006||Weatherford/Lamb Inc.||Method for determining a stuck point for pipe, and free point logging tool|
|GB2158245A||Title not available|
|NO20022539A||Title not available|
|WO1986003141A1||Nov 7, 1985||Jun 5, 1986||Geoenergy International Corp.||Apparatus and method for treating the emission products of a wood burning stove|
|WO1999063282A1||Jun 1, 1999||Dec 9, 1999||Enlink Geoenergy Services, Inc.||Earth heat exchange system|
|WO2004044615A2||Nov 10, 2003||May 27, 2004||Geoenergy, Inc.||Method and apparatus for seismic feature extraction|
|WO2005062196A2||Dec 13, 2004||Jul 7, 2005||Geoenergy, Inc.||Method and apparatus for efficient data acquisition and interpolation|
|1||Prior Art Search on "espacenet" dated Jun. 9, 2007 (8 pages).|
|2||Search Report from the UK Patent Office dated Sep. 6, 2007 (4 pages).|
|Citing Patent||Filing date||Publication date||Applicant||Title|
|US20160230532 *||Nov 1, 2013||Aug 11, 2016||Halliburton Energy Services, Inc.||High Performance Wire Marking for Downhole Cables|
|US20170058662 *||Aug 31, 2015||Mar 2, 2017||Curtis G. Blount||Locating pipe external equipment in a wellbore|
|U.S. Classification||166/250.13, 175/40, 166/66.5|
|Cooperative Classification||E21B47/0905, E21B31/00, E21B47/09, E21B23/00|
|European Classification||E21B47/09, E21B23/00, E21B47/09B, E21B31/00|
|Nov 28, 2006||AS||Assignment|
Owner name: APPLIED ELECTRONICS SYSTEMS INC., LOUISIANA
Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:GIBSON, JAMES GARLAND;REEL/FRAME:018557/0472
Effective date: 20060918
|Aug 12, 2009||AS||Assignment|
Owner name: SONDEX LIMITED, UNITED KINGDOM
Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:APPLIED ELECTRONIC SYSTEMS INC.;REEL/FRAME:023088/0612
Effective date: 20090811
|Mar 14, 2013||FPAY||Fee payment|
Year of fee payment: 4
|Mar 22, 2017||FPAY||Fee payment|
Year of fee payment: 8


text:
Perimeter Hotel is a newly renovated hotel located in Don Juico, Angeles City, Pampanga. Everything here is made for the guests' convenience. Set with a budget-friendly ambiance where every room is provided with air conditioning, cable TV, hot and cold water, free hot tea or coffee and safety deposit box for your valuable items. A Jacuzzi room can be booked for those who want a bigger space and get relaxed after a long tiring day.
We put our hearts in serving our guests with nice, quiet and affordable stay.2 hot bars so you won't miss the fun in the city.
What are you waiting for? Grab the opportunity to be here in Perimeter Hotel!

domain: travel


text:
The Hollows is on the North Shore of Lake Travis, 30 miles from Austin Texas.
Located in the 1,800 acre Hollows Resort is a gated community of custom homes, villas, and home sites
located on the North Shore of Lake Travis; complete with swimming pools, whirlpools, volleyball, picnic areas,
planned activities, swimming, beach entry to the lake, event centers and miles of hiking trails.
Beach Club Swimming Pools
The Hollows Resort offers 4 separate pools; an infinity pool, children’s pool and shallow sunbathing pools.
The Smokehouse at the pool area is a great place to BBQ your own meal. The covered seating area is
perfect for the family or large groups.
Sand Volleyball Court at The Beach Club. Everyone is invited!
Get your own game together.
The workout area at the Beach Club, available for your use.
Join your friends for a quick workout before swimming.
Over 10 miles of paved walking, biking, and hiking trails are at The Hollows.
Bring your dog(s), they will love you.
Key-less locks make entry easy for your family plus you can reset your own code!
You will receive you private code by email or text message before check-in.
The code works from 3:00pm on your check-in day to 11:00am on your check-out day.
Everyone in you cottage can use the code and never need a key!
The Hollows Resort Private Marina
Available for use during your stay when you make arrangements for slip rental from the Marina Staff.
Call 512-635-3166 for information. Voted 2006 & 2009 Marina of the Year out of over fresh & salt water
marinas by the Texas Marina Association!
175 covered wet slips (sizes 8′ – 80′); powerboats, T-head space for houseboats.
Utilities: electric, water, phone, cable, wireless internet
Restrooms + shower facilities
Hospitality deck and kitchen for events
Private swim area
(1 mobile by barge and 1 at store); Boat launch ramp
There are two Smokehouses for your use. One is a Smokehouse at the pool area and another at the top of the Hill.
Use either and cook on the professional BBQ grills and smokers, then relax in the large covered area.
There are plenty of tables for everyone and a GIANT fireplace.
Over 10 miles of walking, biking and hiking trails run throughout the Hollows Resort.


Teen Driving Safety Webinar
Age recommendation: Adults only, Teens
Roads in the U.S. are the deadliest they’ve been in years – and the National Safety Council (NSC) estimates a 19% increase in motor vehicle crash deaths in New Jersey from 2020-22.
Tragically, traffic crashes remain the No. 1 cause of preventable death for teens in the United States, and according to the latest available data, the number of traffic deaths for teens is up nearly 16%.
Needless to say, parental involvement is needed now more than ever, and more must be done to protect future generations by equipping them with knowledge and resources to keep themselves and others safe on the roads.
NSC is hosting a free webinar for parents, focusing solely on New Jersey’s most vulnerable road users and providing crucial driving data, specific laws to know for your state, as well as simple tips and resources for parents to help them stay involved as their teens learn to drive.
Anyone can register to attend this free, virtual event.


text:
Hd — Wake Up, L.A.
The world of L.A. city government is a small one indeed. So small, in fact, that three out of four likely voters in a Los Angeles Times poll published last week said they had not heard or read about Proposition 8, the charter reform measure.
Frankly, we’re not surprised. Despite being the center of a months-long public policy debate, which voters will act on this week, charter reform was never destined to be a hot topic in L.A. It doesn’t involve movie stars, police shoot-outs or weird cults. It has barely received any notice on the 11 o’clock news.
Its sole purpose is to make government work more fairly and efficiently, which, in turn, should make the city a better place to be.
That sounds nice in concept, but it’s a process unlikely to be realized until at least the turn of the century a time frame too far off for many of us to take seriously. It also is being promoted and funded by politicians and friends of politicians hardly an inviting prospect.
Add to that is the internal bickering over how the reform effort should be implemented. A group being led by Mayor Richard Riordan has proposed the creation of an elected citizens’ panel, with the authority to go directly to the voters on charter reform recommendations. Those panel members will be elected this week in addition to voting yes or no on whether a commission should be created in the first place.
The City Council, meanwhile, has created a 21-member appointed panel to overhaul the 72-year-old charter, but the Council maintains veto power on any recommendations. Some Council members consider the Riordan-led approach an effort to provide more power to the mayor’s office.
Given the conflict within City Hall itself, it’s little wonder that so many voters have tuned out.
Establishing the need for charter reform through passage of Proposition 8 is a no-brainer. City government has been paralyzed by a cumbersome, out-of-date charter over 700 pages long that dilutes power to the point where no one seems to be in charge. It also has created an unwieldy structure in which the city budget has ballooned from $1 billion to $4 billion over the past 20 years and where local bureaucrats hold the real power.
The trick is in doing something about it but more to the point, finding commonality in the approach. We support the citizens’ panel approach as the most logical first step in the process and salute the efforts of Mayor Riordan towards that end. (The power-grabbing argument by the Council is absurd, given that Riordan will be out of office long before the updated charter is ever completed.)
Giving the Council veto power on charter reform is a recipe for disaster; it’s like giving college students the prerogative of changing the final grades they receive. Only a body caught up in their own power would offer such an alternative.
The biggest challenge, though, is generating a broad-based interest in the process. On this front, we are not encouraged (and Tuesday’s expected low voter turnout doesn’t raise our hopes). It goes without saying that L.A. is not an especially civic-minded town, and getting the attention of the community at large on something as complex as a city charter will not be easy. Frankly, it might be impossible.
But the only thing worse than not changing the charter is changing it with minimal representation. That’s a real recipe for disaster.

domain: sociology


text:
Hello! I do not have a response regarding what you should take, BUT want you to know I am exactly where you are! Three level lumbar fusion on 02/05/18, no staples thank goodness (they used glue), but am weaning myself off of pain meds ( I don’t like their side effects, as you stated). Weaning off the pain meds leaves me susceptible to flare ups when I do my PT or go for my daily walks three times a day. I surely hope someone answers the question you posed, as I would like to know! Wishing you the best of luck in your recovery! Stay strong!
The compounds found within cannabis (known as cannabinoids) are very similar to the ones produced naturally by our bodies. These cannabinoids have been observed to relieve the symptoms of various conditions by attaching themselves to particular receptors in the brain, thereby blocking or boosting certain signals. This can help bring calm to an otherwise stressful situation.
CBD (Cannabidiol) is a naturally occurring compound found in the hemp plant (Cannabis Sativa). NuLeaf Naturals firmly believes that our organic CBD oil may improve the lives of individuals suffering from certain mental and physical ailments. The best of today’s science is on our side. A nonprofit called Project CBD has examined a wealth of peer-reviewed scientific research and concluded that cannabis oil may be therapeutic for individuals with conditions such as:
MMA fighter Joe Schilling describes (paraphrased) how cannabis oil killed cancer in his father, “I was able to visit my dad in the hospital. My dad’s prognosis was that he was going to die soon from cancer. He agreed to Cannabis Oil therapy, with CBD but not THC. There was cancer in his lung, cancer in his brain, cancer in his chest, a massive tumor was on his neck. We gave CBD oil to him for something like 7 months. He decided against chemo, he did not want to do it.” Schilling notes his father’s poor diet choices and refusal to take vitamins and states, “the doctors did their tests and graphs, you know the things that they do, and amazingly, 90% of the cancer was gone. I have no doubt what so ever that it was the CBD oil that killed the cancer because he was doing absolutely nothing else correctly. The 10% of the cancer that was still alive was surrounded by dead cells and was going to die out too.”
Due to hemp’s identity as a bioaccumulator, it is incredibly important that any products made using hemp are properly tested for any outside contamination. HempMeds® does just that – three times over – in order to produce the safest products on the market. Our safety tested process starts at our hemp’s harvest, where it is tested for outside contaminants. Following importation into the U.S., our CBD hemp oil is tested again by an ISO / IEC 17025:2005 accredited lab to check for microbes, mold, heavy metals, and other possible contaminants, as well as for potency of the cannabinoids present. Finally, after our hemp oil is formulated into our many products, they are batch tested to make sure that the final product is ready to be shipped to your door and safely used by you and your family.
Good morning! I’ve been researching CBD oil for a couple of years and I’ve tried a few CBD oils. I am very satisfied with the one I am presently taking which meets all of the requirements stated, organically grown in the US, laboratory tested for quality etc . If anyone would like more information I’d be happy to help. Just shoot me an email at [email protected] I’m a firm believer in the benefits of CBD oil and finally found one that works for me!
If you are vaporizing CBD-dominant strains of cannabis, bioavailability is through the alveoli, tiny sacs in the lungs, clarifies Kilham. If you are taking CBD strain capsules, he suggests eating some fat or oil, like a handful of nuts or some full-fat yogurt, to improve absorption and bioavailability. Cannabinoids are fat-loving molecules. They are taken up readily into the small intestine with a bit of dietary fat.
Unfortunately, it’s not always easy for consumers to determine which CBD brands and product claims’ are trustworthy. With the growth in popularity of CBD oil, new brands and merchants are coming out every day with promises to offer you the best, high-quality supplement. However, there are few regulations, if any, to help monitor and regulate these claims.
Some industry insiders argue that organic, pharmaceutical-grade ethanol, which is a grain alcohol, is optimal and eliminates certain toxins and residues in the raw plant material itself. But others say that while this extraction method yields a high amount of cannabinoids and is GRAS (Generally Recognized as Safe) for human consumption, it destroys the plant’s waxes, leading to a less potent oil.
It’s a truism to state that pain is an inevitable part of life. And it’s true that we all, from time to time, experience pain that is short-lived and treatable. But those who deal with chronic pain know the debilitating, life-sucking reality of this condition. And traditional medications often come with long lists of side effects which can be as debilitating as the pain itself.
The manufacturer will probably give you a recommended dosage, but bear in mind that this isn’t set in stone. What you need to find is your own minimum effective dose. “Minimum effective dose” is a medical term which refers to the amount of a substance you need for the results you want, and above which, the substance doesn’t increase in effectiveness.
The main difference between CBD and Hemp is that Hemp does not contain CBD. CBD and hemp oils are made from different parts of the plant and have different purposes. CBD is a compound found in industrial hemp, and we utilize a whole plant CO2 extraction that allows us to draw the CBD from the plant material and filter out unnatural substances, maximizing pure CBD concentration. While CBD is extracted from the entire plant, minus the seeds, hemp is extracted only from the seeds. Hemp oil is made from pressing hemp seeds and is used in a variety of products. Hemp-seed oil is used as a protein supplement for food, as varnish for wood and, because of its remedial properties for hair and skin, as an ingredient in lotion and soap products. You can buy hemp-seed oil online or at certain food stores, where you can learn about more ways to incorporate it into your diet and hygiene. CBD oil is generally used for medicinal purposes and has shown great promise in treating inflammation, pain, sleeping disorders and even certain types of epileptic seizures.
I appreciate your efforts in writing this article & don’t mean to disparage you, but there’s so much information that goes into this discussion & people need to be prepared ahead of time. One very important note is to make sure that nothing in the CBD will be contraindicated with many prescription medications, especially for diabetes, hypertension, blood thinners & anti-platelets for example. If a company’s website says their formula is a “proprietary blend”, call before you buy, please!
“Barely in its infancy, the CBD medical market is still largely unregulated; quality control is meager at best, and consumers are largely unaware what to look for when shopping …,” explains Carlos Frias of the Texas Wellness Center. Frias, who has been with the cannabis industry for more than 15 years, has seen, firsthand, the shadiness that exists in the CBD market.
This is a hugely beneficial effect of CBD. Free radicals are the culprits when it comes to oxidative damage and inflammation. But CBD’s antioxidant properties can help to combat the negative effects of everyday exposure to elements that increase the production of free radicals. These elements include pervasive, but hugely unsurprising, things like:
However, since the 1950s it has been lumped into the same category of marijuana, and thus the extremely versatile crop was doomed in the United States. Industrial hemp is technically from the same species of plant that psychoactive marijuana comes from. However, it is from a different variety, or subspecies that contains many important differences. The main differences between industrial hemp and marijuana will be discussed below.
CBD in all forms has enormous potential. Doctors are excited, the wellness community is excited, and I personally slather hemp CBD on my face to keep eczema at bay and put dropperfuls under my tongue to deal with anxiety. But, like all things marketed as panaceas, be skeptical and do your research before buying. If you’re interested trying CBD, always talk to your doctor first (particularly if you’re on other medication, which can interact with the cannabinoid). Start with a small dose and work your way up
Are you looking to buy CBD-rich oil? Finding the right CBD oil can be a daunting task, especially if you are a newbie. There are many ways of acquiring your Cannabinoid (CBD) oil. You can purchase the product online, from brick and mortar store, co-ops, dispensaries, and natural herbalists. CBD oil products can be made from extracts of either hemp plants or Marijuana Plants. Depending on your preferred mode of ingestion, the hemp-extracted oil is available in a range of applications including tinctures, topicals, vaporizers, vape pens, transdermal patches and as infused edibles.

domain: chemistry


text:
"My impression," [Kwame Anthony] Appiah writes, "is that many well-intentioned, non-racist academics … who are not black, feel that in criticizing" certain ideas "they risk … exposing themselves, dare I suggest, to the risk of being accused" of "contributing to racism." This is not, he goes on, "to put it mildly, in the best interests of learning," and "it is also often condescending," reflecting as it does "a refusal to think seriously about racism" and to make it possible "to distinguish racism from other things." And thus do we find that ideas — even ideas like "racism," "privilege," "microaggressions" — can come to lead lives unimagined by their progenitors. "Stalking a lost deed," said Milan Kundera 40 years ago, of those Czech intellectuals who found, to their horror, that they had given their allegiance to platinum-plated "progressive" ideas that would soon be used to betray them or silence them.
Saturday, March 19, 2016
… How 'Safe Spaces' Stifle Ideas - The Chronicle of Higher Education. (Hat tip, Dave Lull.)


ROLL ON TO ZOOM IN
DPMS Panther Arms .308 Oracle A-TACS Centerfire Rifle
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text:
THANKSGIVING SIDES (32)
LIBBY'S® PUMPKIN (20)
LOW CALORIE (17)
SMOOTHIES AND SHAKES (20)
|EVERY FEW MINUTES|
|Spices: Seeds and Barks Bantam Library of Culinary Arts|
|by Jill Norman|
Part of a series which contains information about traditional and nouvelle food, including the revival of forgotten dishes and original recipes fr...
Tip: Try seed cucumber for more results.

domain: food


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text:
FORT MYERS, Fla. — A small group of protesters stood along Colonial Boulevard Wednesday, holding signs and waving flags.
They believe masks at school need to be a parental choice and not the schools.
The group is calling for parents to decide when it comes to masks on Lee County School campuses this school year.
The School District is currently making them mandatory for everyone.
One parent Fox 4 spoke to says she consulted with two doctors and then made an educated decision. She believes the decision should be left up to the families themselves.
The protesters say they will not stop protesting and would like a meeting with the school district to discuss other options.

domain: news


text:
This cool little cabinet not only gives you extra storage space but will also decorate any room it's placed it. It's made of mango wood crafted with a detailed pattern in the door that resembles beautiful and majestic mountains. A fine contrast between the organic wood and the cold and hard mountains that are pictured on the front. The natural colours of the wood may vary which makes every cabinet unique.
Estimated delivery time 2-3 weeksL40xH60xW30cm

domain: design


The sartorial confusion of Pervez Musharraf is deepening. Yesterday the Pakistani president swept through hishilltop palace wearing a smart dark suit and polished shoes. But the power behind him, as ever, was pure khaki
Leader: The answer is that this is no mere fad; the dollar's slide has been coming for ages. Although it has turned into an outright plummet since this summer's market turmoil, the currency has been in gradual descent for about five years.


text:
Tabor City ('teɪbɜːr ) is a town in Columbus County, North Carolina, United States. It is the southernmost town in the county. It is located just north of the North Carolina/South Carolina line, about north of Myrtle Beach, South Carolina, and is just north of Loris, South Carolina. The population was 2,511 as of the 2010 census.
According to Swanton (1952), before the arrival of the Europeans, the area was home to the Cape Fear Indians, the Waccamaw Indians, and the Saponas.
During the Revolutionary War, men from the area joined with the rebels in the Battle of Brown Marsh. The Loyalists won, marking the high point of their efforts to defeat the revolution in the southern theater. Men from the area may have also aided the American forces in the Battle of Moore's Creek Bridge, which had a much more favorable outcome for the Americans. The Siege of Charleston saw troops from the coastal Carolinas unsuccessfully defen

domain: history


• Ideal for commercial use. Includes a carrying case with
• Highly efficient and accurate due to its advanced
• Hold Function: saves measurements for convenient
reading and recording.
• Auto-off function: the meter shuts off automatically after
10 minutes of non-use to conserve batteries.
• Measurement Range: 0-9990 ppm. From 0-999 ppm, the
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• Display: large and easy-to-read LCD screen.
• Factory Calibrated: the meters are calibrated with a 342
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• Very Affordable
• Warranty: 3 Years


SREE KAVITHA ENGINEERING COLLEGE
UNDER THE SUPERVISION OF:
Karepalli – 507122,Khammam Dt, TS
ELECTRONICS AND COMMUNICATION
A LANE BOUNDARY DETECTION
METHOD BASED ON HIGH DYNAMIC
• HDR CAMERA
• LANE DETECTION OF HDR IMAGE
• MERGING OF IMAGES
• DIFFERENTIAL EXPOSED IMAGES
• MERG HIGH DYNAMIC RANGE IMAGE
• IMPROVED METHOD BASED ON HDR
• ADVANTAGES AND DISADVANTAGES
• CONCLUSION AND FUTURE SCOPE
Every year many vehicle departure accidents
happen due to the driver's carelessness.
Lane Departure Warning System (LDWS) is a kind of
system which can relieve the stress of the drivers and reduce
But most traffic scences have greater dynamic range than
digital camera at present.
ADAS are systems which can help the drivers in their driving
process. They are designed with a safe Human-Machine Interface and it
should increase car safety and more generally road safety.
Nowadays the most common ADAS are navigation system, adaptive
cruise control (ACC) system, lane departure warning system (LDWS), lane
change assistance system, collision avoidance system, night vision, traffic
sign recognition and so on.
Dynamic range is the ratio between the largest light intensity and the
smallest possible light intensity values in a scene. The dynamic range in most
scenes in the natural environment is larger than 10^5
DIFFICULT SCENES FOR LDWS
Affected by adverse light conditions such as reflective road
surfaces, road with the shadows of the trees
LANE DETECTION ON HDR
TAKE DIFFERENTLY EXPOSED IMAGES
Tocci’s method is the most suitable for the real time
system like the lane departure warning system.
Images taken by a camera continuous with changing
exposure time. In the first row, the images exposure time are
1/250 second, 1/1000 second, 1/60 second. In the second
row, the images exposure time are 1/60 second,1/250second,
We can find out a lot of pixels are white in the properly-
exposure image., and in the under-exposure image most
pixels are almost black while in the over-exposure image
most pixels are almost white.
HISTOGRAM OF THE PROPERLY-EXPOSURE IMAGE HISTOGRAM OF UNDER-
HISTOGRAM OF THE OVER-EXPOSURE
LANE DETECTION OF HDR
RECOVER THE RESPONSE FUNCTION OF THE CAMERA:
We use the method Debevec proposed to calculate the
response function .Let us call the response function f. It can
be assumed that Zij is the gray scale value of the pixel which
is numbered i and exposure time is Δtj. Ei is the real
luminance of the point in the scene that pixel i take. They
meet the equation as:
MERG OF HIGH DYNAMIC RANGE
We use the differently exposed images and the
camera response function to merge a 32 bit
image and then tone mapping it to a 8 bit
AUTO EXPOSED IMAGE AND HDR IMAGE OF THE SAME SCENE
HISTOGRAM OF THE HDR
Edge detection of the image is to detect the
edge of the surrounding pixels have a gray-scale
step-like changes or changes in the roof of a
collection of pixels. In the images taken for lane
detection, the lane in the image is different from
the road. So we can detect the lane use EDGE
We use Sobel operator to detect the lane
boundary. The Sobel operator use the weighted
difference of the gray scale value of the field
point of each point in the image.
Before detect the line, we should do the image threshold
segmentation first. Image binaryzation is the procedure of
separating the target and the background.
The algorithm assumes that the image to be thresholded
contains two classes of pixels or bi-modal histogram,
then calculates the optimum threshold separating those
two classes so that their combined spread.
The final step of the detection is to detect the boundary of
the lane. Most of the lane are straight line or clothoid curve,
we can use hough transform to detect the line.
Carried out in voting procedure.
This voting procedure is carried out in the parameter space,
in the parameter space the object candidates are obtained as
local maxima in an accumulator space that is constructed by
the algorithm for computing the Hough transform.
IMPROVED METHOD BASED ON HDR IMAGE
Exposure fusion is an alternative way to merge high dynamic range
images. Compared with the traditional HDR merging method, it
leaves out many computation procedures. By fusion the different
exposed images, the image has greater dynamic range than one
image. But without scientific calculations, the image merged by
exposure fusion is not as good as the image merged in the
traditional HDR merging method.
The improved method
As we all know, color image has red, green, blue channels, in the high
dynamic range merging procedure, we should calculate three times to merge a
HDR image. And the time of calculate one channel is very long. But the
computation on binary images is very quick.
So we propose a improve method.
The lane detection procedure of the method based on HDRimage is as
shown in and the lane detection procedure of the improved method
Exposure fusion in the improved method
The lane detection system is a real-time system. We should consider the
computation time first.
If we choose a complex exposure fusion method, it will not use in a real
lane departure warning system.
PROCEDURE OF THE METHOD BASED ON HDR IMAGE
FLOW CHART REPRESENTATION
PROCEDURE OF THE IMPROVED
Lane Departure Warning System (LDWS) is a kind of system
which can relieve the stress of the drivers and reduce traffic
The high dynamic range image can improve the accuracy of the
lane detection method.
We proposed an improved method based on exposure fusion to
reduce the computational time of the system.
Processing of merging HDR image is very time consuming. It
makes HDR image can't be used in real-time LDWS.
We proposed an improved method based on exposure fusion
to reduce the computational time of the system.
After a series of experiments, we get the
computation time use each method. The average
computation time on a single image is about 40ms, the
average computation on HDR image is about 2 seconds, and
the computation time use the improved method is about
100ms. We can get the method based on high dynamic
range images cost too much time, it can’t be used in the
system. But the improved method based on exposure fusion
costs about 65ms, it can be used in the real-time system.
Edge detection result of the auto exposed images
and high dynamic range image
We use three images with different exposure to merge a high dynamic
range image and detect the lane in the HDR image.
The experimental results show that the high dynamic range image can
improve the accuracy of the lane detection method. However, the processing of
merging HDR image is very time consuming. It makes HDR image can't be
used in real-time LDWS.
We proposed an improved method based on exposure fusion to reduce the
computational time of the system.
The average computation time of with the improved method based
on exposure fusion is about 100ms. It meets the need of the lane
departure warning system.
In order to detect the lane in the image, future work on develop a
high dynamic range camera system should be excavated and utilized.
By incorporating a departure warning system, the functionalities of
the lane marking system can be enhanced.
Hough transform can be implemented on FPGA board. FPGA
implementation consumes less power also it is very compact and fast.