Reliable Level in Solids Using High Power Small Package Design

How many more technologies will emerge in the world market for measuring continuous level for solids and liquids materials? It seems to be an unending barrage of advertisements with statements of performance, high success, breakthroughs, reliability, and on and on, but are these level technologies really fact or fiction in their claims? With all of the level technologies at the availability of end users, it is becoming really difficult for people to make a wise selection of what technology will provide them with the best results for their application. There are many factors involved in deciding which technology is best suited for a level application, not to mention the thoughts of the technologies cost, the installation time, and the learning curve, if any, on the technology chosen. In the market for level measurement, there are technologies that are being pushed as the end all, beat all solution for liquids and solids level, but let me tell that there is no universal technology. There are some technologies that will have a broader application base for solving level, but never, ever rely on just one for your measurements. Focusing on continuous level will be the direction of this article and a detailed discussion on the mystique of microwave radar as the "chosen" technology.

Is it the panacea for all level applications? The answer is absolutely not, as overshadowed in the background of this highly promoted technology is the technology of acoustic wave. Not to be mistaken with ultrasonic wave, but this acoustic wave technology uses low frequency design harnessed within a short cylindrical, but narrow diameter transducer package. Different than anyone else on the market today, but this unique design drives the low frequency resonating mass to produce a pressure wave at the face of the transducer. With this pulsing to the face of the sensor, there is a self-cleaning effect that eliminates any type of build-up. So, low frequency (5 KHz to 30 KHz) combined with high power provides measurement capability in the toughest of applications. Now, I am not saying that acoustic wave technology is the chosen "ultimate" technique for measuring level. There are technologies and there are application conditions, and the two items have to be considered together and not separately. Many companies make the mistake of trying to shoe horn fit one technology into a plethora of applications, and this does not work well at all. Understand the application, and what the parameters are, as well as the customers' requirements, and then discuss the technology for the measurement.

So, if there isn't a universal technology for measuring level in liquids or solids, why is microwave radar being sold into a large majority of level applications? It is being falsely promoted as the solution to almost every application, and has claims that it can perform under all conditions of duress. Conditions of duress would be heavy dust in the airspace, heavy build-up on the antenna emitter, wet and moist conditions, the ability to read through foam, high temperatures, and just plain every other condition that other technologies fail at. Many, many times over, one can visit a plant site and see microwave radar designs installed in applications where they should not have been used, and yet they were embellished to be the solution. With microwave radar technology, like any other technology in the marketplace, there are advantages and limitations for its applicability and performance success. These things need to be understood by the end users.

Microwave radar is not the ultimate solution for all level applications, and that's what this article will further point out. For this technology, difficult application conditions for liquids such as heavy vapors above the liquid surface, high temperatures beyond 300 F, pressures in excess of 50 psig, and turbulent conditions on the material surface would deem this technology as the most suited. It does not mean though that another technology could not be considered such as guided wave radar, capacitance, or differential pressure, but when presented with conditions, it makes sense to evaluate each technology and perform a process of elimination. With these conditions stated, would traditional ultrasonic be applicable? The answer is no and the reason being is that the vapors from the hydrocarbon will stratify with the changes in temperature in the vessel. The speed of sound depends on the temperature of air and it highly affected by the vapor density in the airspace. Errors in the measurement will occur if the air medium is different than pure air as the sound wave will be somewhat attenuated and travel will change. Additionally, the ultrasonic technology will be affected by the condensation in the vessel caused by the changing temperatures, as traditional ultrasonic is usually transducer frequencies of 40 to 55 KHz. With this higher frequency band, there are no self-cleaning properties because there is not enough power to create a pressure wave on the transducer face. So microwave radar would be an ideal choice for this liquid application.

As seen from above in the liquids market, microwave radar has its place and can work quite well in applications, especially when there are some harsh conditions like heavy vapors, strong turbulence, and temperature/pressure extremes. But again, it is not the broad brush solution to every level application, and that's what has to be understood. Level applications that have build-up as a possibility are a real question mark for any technology. Applying a contact technology in an application with build-up or coating is not the smart choice. In that case, the application of a non-contact technology should be the first thing on the mind and then the thought about the type of build-up. Regardless of the build-up on the sensor of microwave or acoustic wave, there has to be either maintenance schedule of cleaning performed on a periodic basis OR the use of a self-cleaning technique to keep the build-up or coating off of the transducer face. It's not to say that acoustic wave is the solution with any build-up, as it does depend upon the dielectric of the build-up from a microwave radar standpoint, but in general, the high power pressure wave created does eliminate the coating from happening.

Now, when the application involves the measurement of solids materials, like powders, grains, metal ores like copper, iron, coal, and cement materials, then applying the right technology takes additional thought. From a microwave wave radar perspective, the technology was introduced into the solids level market in the 2003 timeframe, and was promoted as being the new technology for measurement in all solids applications. Think about it from a level standpoint, a technology that could be the solution to difficult solids applications with conditions like heavy dust, dealing with angles of repose, long range measurements beyond 200 feet, high temperatures, and more. Although the technology sounds admirable and stellar in thought, it doesn't fit the bill from a universal applicability standpoint. It has hit the level market and portrayed as the technology that could provide reliable and accurate measurements under any conditions. The microwave technology absolutely took the level market by storm, and in many cases, cannibalized other technologies in the process, especially in the solids industry. The use of non-contact ultrasonic and acoustic wave has taken a direct hit from a loss of sales standpoint and it is a result of the over promotion of microwave radar.

Certainly, the technology does warrant merit as it is a very solution oriented design, however, when it comes to solids and the addition of moisture into any application, there are no self-cleaning properties like acoustic wave. With the measurement of solids, it must be emphasized that there are industries that have dry solids, and then applications which have moisture. When one speaks about the mining industry (coal, non-ferrous and ferrous minerals), reducing the heavy dust in the environment through the use of water sprayers is an absolute necessity for the work force. There is so much excessive dust throughout a mining site because raw rock and ore material is transported to machinery that performs crushing, movement via conveyor belts, dropping from one transfer chute or another, and is a dust nightmare. So with that said, most mining operations today will make use of water in a spray form that is located at filter screens, ROM bins, rock crushers, conveyor transport, and many more. With powder and water mist combined, the parts of any containment, conveyor belts, transfer chutes, and such will be coated with heavy scaling or build-up. So for level measurement and the notion to keep things clean so that performance can continue, either there has to be lots of periodic maintenance to keep the sensing elements clear of coating or the technology must have that feature built in somehow. Hereto the technology of acoustic wave which has the built in capability to keep the propagating sensor surface free of coating or build-up regardless of the material being wet or dry.

This technology of acoustic wave is what I would refer to as a diamond in the rough, or a pearl hidden behind the shell simply because it has been considered to be the same as ultrasonic technology. Ok, the technologies are similar; however, there is no comparison when it comes to performance in tough solids applications with heavy, wet build-up, moisture in the environment, or shear brute transmission over long ranges in the nastiest airspace conditions. And the magic behind this acoustic wave technology is not just the frequency, as it is a combination of low frequency, like 20 to 5 KHz, along with high power to a narrow diameter balanced resonating mass, and adaptive modulating gain control. Actually, the secret is in the formula for all three of these variables, which is mechanical transducer design, power & energy distribution, and adaptive software control. In the solids industry and level measurement, it isn't just software that will yield the successful results for these harsh application conditions.

When applying acoustic wave technology, the choice of the transducer frequency is not based upon the range of the measurement, but it is really a function of what's in the containment. And with low frequency, high power acoustic wave, it's not really how dusty the airspace above the surface is, but more about the environment inside the containment. If there is moisture, then the frequency will need to be lowered, and accordingly, the power to move that larger resonating mass is taken into account. Let it be understood though that with lower frequency, the energy to the transducer is NOT increased, but distributed differently so that there is focus out into the airspace and not elsewhere. The acoustic technology is not affected by moisture content from an operational standpoint as would microwave radar. Remember that microwave radar is a function of the dielectric value of the material. With air being 1 and water being 80, the low dielectric materials of 1.5 to 10 are insulators, and will be fairly non-absorbing of microwave signals. If the microwave radar transmitter is measuring dry powders, and there is a dust cover over the antenna, then the application is relatively easy. Adversely though, and this is important to understand, that if there is any moisture entrained or apparent in the solids material that causes coating or build-up, then the microwave non-contact radar is virtually doomed for successful performance. The acoustic wave technology is not affected by the coating or build-up because the low frequency and high power create strong frequent pressure wave activity on the transducer face and this keeps the material off. This pulsing power on the transducer provides the self-cleaning feature that gives the performance under these tough conditions.

In addition to the self-cleaning properties for clean signal propagation on acoustic wave in wet, moist dusty environments, it is of great merit to discuss the other noted features that allow this technology to stand out amongst others and raise this sleeping giant of a technology.

The low frequency combined with the high energy allows this design to be used in solids applications without the typical aiming assembly for dealing with angles of repose. Enough focused energy is produced from the transducer face, and then a focalizer is used to harness the energy so that signal reflection back from the material surface is collected.
Inherent false echoes and excessive ringing will occur with traditional ultrasonic technology as most of the transducers are mounted onto flanges that contact metal containment structures. A simple acoustical coupling abatement flange is designed now to completely isolate the transducer and eliminate the ringing issues.
Acoustic wave design is impervious to any crosstalk directly related to electrical noise (variable frequency drives, pumps, etc.) because the signal coming out of the transducers are digital RS485 in their output and not some small millivolt output. Additionally, with the balanced transducer design at the crystal array, any noise is also not a problem.
Acoustic wave technology deals extremely well with low bulk density materials. The issue with low bulk density materials (lightweight powders that have a soft surface) is that energy from microwave devices will allow the energy to pass through the material, and provide a small amount of reflection back, but mostly propagate through the material and reflect off of the metal containment bottom. Obviously, this is not an accurate measurement. The acoustic wave technology will allow much of the signal to reflect back due to some design features, which makes it ideal for these applications.

The message that should be clear from this article is that every technology for level measurement has its place in applications. Whether it is liquids or solids materials, the selection of the technology must be reviewed carefully and all application conditions of dust, condensation, wet material, turbulence, mounting, surface conditions, temperature & pressure, and many more have to be considered. One technology like microwave radar should not be considered the universal solution to all level measurement applications. As pointed out in this article, there are other technology solutions that will fit more appropriately in an application, and one that has been lying quietly in the background like acoustic wave, especially for nasty solids materials, fits the conditions to provide top notch performance. With almost 30 years of experience in the level industry, it has been seen countless times where a microwave radar design or other technology has been installed in the wrong application, yet it was promoted to the customer as the right technology. The hype for microwave radar needs to be filtered, as it is being sold as the technology for anything, when in fact it is finding more problems now as the application installed base increases. Don't overlook the sleeping giant of acoustic wave as good things can come in small packages.

Applying the right level technology is an engineered process, and should not be a commodity sale. A careful review of the application conditions as well as the customers' requirements should be examined before just offering something that has been promoted as the ultimate solution. Whether the customer is in the liquids or solids industry, the right level solution will provide many years of good successful performance with a low cost of ownership.

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Advantages Of Small Chamber Confocal Sputtering Equipment For Research And Development

One popular method of Physical Vapor Deposition (PVD) is Sputtering, which has numerous product applications. Whereas commercial Sputter systems are often geared to large scale production volume of established processes, there is also a need for smaller scale sputtering systems for research and development where versatility is generally more important than volume throughput. These same smaller sputtering systems can also serve for lower volume initial production.

This paper will discuss some of the features and capabilities that can be available in smaller Sputter systems geared to low volume work such as research and development, in particular the use of a confocal arrangement of multiple targets around the perimeter of a circular rotating substrate stage, all angled in toward it.

Smaller chamber size has advantages of lower cost and smaller laboratory footprint, and the use of small circular cathodes also limits the investment required for target materials. At today's prices, a large gold target may cost nearly as much as the piece of equipment. Also, those small circular cathodes, available commercially from several sources, almost always have clamp on targets, making target material changes fast and easy and making it practical to be able to own and utilize targets of numerous different materials to support development work on many fronts.

It is possible to configure such a system in any desired orientation, for sputter down, sputter up, or sputter horizontally. This full tri axis capability can utilize any desired pumping configuration such as cryo or turbo. It is also possible to have just a simple single chamber, to be fully vented for loading and unloading, or to add either a manual or mechanized transfer arm load lock.

One key configuration element for maximal versatility is a rotating substrate stage centered within a ring of cathodes such that they are all angled in toward it in a confocal arrangement giving each the ability to provide adequate deposition coverage across the entire stage surface as it rotates, giving acceptable uniformity on the substrate or substrates. With adequate power supplies and controls, these cathodes can be fired individually or can be fired two (or more) at a time for co-deposition.

Any desired type(s) and quantity of cathode power supplies can be used, such as RF, DC, or pulsed DC. But these power supplies will be smaller than the ones required for large high volume tools, and thus less expensive, and the lower power cathodes reduce the demand for such facility support as total electrical power required or cooling water required.

Gas systems can include multiple gas channels, as would be desired for reactive sputtering, and can have either upstream or downstream pressure control as desired.

Another feature that can add to the total versatility for experimentation and process development is to have substrate stage temperature capability. Most commonly this is a stage heater, but some degree of cooling, while a bit more involved, is also possible. Such optional things as substrate bias can also be done, as well as features such as sputter etch or ion beam.

The number of cathodes, as well as their physical position and orientation, can be fixed - the lowest cost option - or can have some degree of mechanical adjustment capability such as angle or distance.

Obviously, adding more cathodes will force a somewhat larger chamber, and each additional cathode or power supply or other feature mentioned above carries some cost elements,. But if the features are needed, they are needed, whether in a smaller platform or a larger system. In general, any feature that could be put in a large system could be put in a small one.

Adding features to the smaller sputtering system will undoubtedly cost less than adding the same features to a larger, higher throughput system. This smaller chamber, confocal cathode array approach remains a viable way to have all the features you need at a lower cost than most other approaches to configuring a sputtering system to support development work, whether in a commercial facility or a university laboratory.

Author Norm Hardy's a Process Engineer at Semicore, a worldwide supplier of high performance Physical Vapor Deposition PVD coatings on a variety of materials. To find out more about Semicore's PVD Coating Equipment, and magnetron sputtering systems please visit our website http://www.semicore.com/sputtering-systems

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Dedicated Server Hosting - Starting Small

If you're on a budget or have been troubled paying rented servers lately, then it's time to create your own dedicated server once and for all. Creating your own dedicated server can help you save up - not just from monthly bills - but with extra cost. Extra cost that is derived from extra services from your host company. Extra services which you can do on your own.

Server hosting also gives you the opportunity to make business out of it. Yes, if you have a computer - which is updated (recommended), a good router, and an unlimited internet connection, then your set to have your own dedicated server. You might also need to provide a network attached storage for data storage purposes.

By the way, how will I create income with it? You can create income by being the server instead of renting the server. You can start with small business server hosting. You can lease the extra space on your server to others. This is often called as virtual hosting.

What do I get when I start my own dedicated server? Aside from generating income, you will also have enough bandwidth for your business. You will have unlimited websites, storage, and databases. You will also personally monitor them 24/7. And freedom from paying bills.

Hosting a server is a great business nowadays. Businesses are starting to evolve. E-commerce is everywhere. And almost everybody has a website. Your market will be targeted on small scale and middle scale businesses. But it won't be long, you will become a competitor of your previous hosting company.

Although, there are major considerations when hosting a dedicated server. First, you will need to have a background of networking, scripting languages, and databases. You will need to manage all the processes involve in a server hosting business. But don't worry about that, there are lots of schools offering such courses, and no later in time, you will hire specialists to do the work for you.

You can also engage in business with email host providers. Or be an email host provider instead. Perhaps, that could also be an added feature for your hosting services.

As you can see, there are good things you can get from hosting your own server. Aside from the money, you are in control of all data. Plus, you can utilize your extra computers to expand your network. You can earn up from $ 300 to $ 500 dollars a month with just one customer. Of course, that's less the extra services like 24/7 monitoring, higher-type of security, and extra email service.

And come to think of it, you will have no problems expanding your other business online since you own all the space. And who knows, Google might find your hosting business competitive and feasible? Who knows they might do business with you.

If you have enough capital and equipments right now, why don't you start hosting your own server today? Don't worry about the technical requirements for now. Just think of how much money and influence you can acquire from hosting your own dedicated server.

Find out more how to start your small business server hosting for free. Razon L. Quin is an e-commerce consultant and affiliated with giant email hosts providers.

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iPad Development For Small Businesses - Tips On How To Hire the Right iPad Developer

The roaring success of the first iPad captured the interest of entrepreneurs worldwide. The unparalleled success of later versions of iPad demonstrated that this Apple device is here to stay. During the last couple of years, numerous businesses have harnessed the power of iPad apps to generate revenue and promote products. While it is easy for large companies and organizations to hire iPad developers from India, China, Philippines or Indonesia to cut down the cost of iPad application development, most small businesses and entrepreneurs find it difficult to take full advantage of offshore software development.

As the iPad grows more and more popular, small businesses and start-ups across the world are opening their eyes to the benefits of developing an app for iPad. However, the high costs of app development in US, UK and Europe make it difficult for them to benefit from iPad app development. Offshore development is a seemingly simple solution to this problem: small businesses can reduce the cost of development by 50-60% by outsourcing their IT projects.

Unfortunately, iPads have not been around for a long time. So, it is not very easy for entrepreneurs to find competent developers who can do justice to their project. Large organizations have extensive experience with offshore development, and they can afford to spend a more money. Consequently, they do not face too much trouble in finding efficient iPad developers. But things are not that easy for entrepreneurs or small business owners. If you are a small business owner or entrepreneur, the following tips will help you hire a decent iPad developer for your iPad app development project:

Freelancer vs. Professional: If you are planning to develop a simple app, you can hire a freelancer to build it for you. Freelancers are usually ready to work for cheap, but it is difficult to find trustworthy freelance developers. On the other hand, hiring a reliable iPad developer from a reputed offshore company will cost a tad more. First, you need to decide whether you want a freelancer or a professional.

Check Background, Seek References: If you are planning to hire a freelancer, you should insist on seeing references. There are too many frauds out there who'll take your money and vanish into thin air. Even when you hire iPad programmers from a company, it is best to check their background. LinkedIn can be a pretty useful tool in this situation. Also, hiring someone who has references from your friends or acquaintances is a good idea. Do not hesitate to ask for references and work samples - most of the genuine developers will be more than happy to oblige.

Talk with Others Who've Done It Before: It should not be difficult to find friends or business acquaintances who have successfully outsourced their iPad development projects. If you are unsure of what you are looking for, talk to a friend who has some experience of offshore development. This will also help you get a clear idea of how outsourcing works.

Understand iPad Development: Many small businesses get ripped off because they do not know anything about the development process. You need someone in your company who understands the basic of iPad app development. Discuss different aspects of your project with the potential hires and let them see that you know a bit about iPad programming.

Ask Questions: It may not be possible for you to discuss technical details, but you can question your potential developer regarding the process of development. Ask him about the tools and technologies he intends to use; ask him to give you an exact date of delivery. Depending on the scope and complexity of the project, tablet app development may take as long as 2-6 months or as little as 2-4 weeks. If you are planning to develop a simple, conventional app, it shouldn't take too long to develop.

While it may not be possible for you to follow each and every tip, you can apply some of the ideas in this article to evaluate the suitability of the iPad developers. Even if you do not have the time to understand the basics of iPad development, you can get a clear idea regarding the suitability of a programmer by looking at his previous work. In addition, talking to the iPad app developer will also help you get some idea about his suitability or unsuitability for your project.

With many options available on the market, you can hire expert iPad developer from a reputed offshore mobile and web development company. You can get customized iPad applications at affordable rates without compromising with quality.

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