Superconductors and Superconductivity :: physics science superconductor

Before Kamerlign Onnes, in 1908, was able to liquefy helium and bring its temperature down to about 1K, it had been known that the resistance of a metal falls when cooled below room temperature. However, it was not known what value the resistance would approach if the temperature was reduced towards 0K until Onnes, while experimenting with platinum, discovered that, its resistance fell when cooled to a very low value that depended on the metal’s purity. As the temperature of mercury was reduced toward 0K, the value of the resistance would fall smoothly until the resistance fell extremely suddenly at about 4K. Below 4K, mercury passed into a new state with electrical properties unlike those previously known: this new state that mercury had entered was called the â€Å"superconducting state.† Superconductivity can be destroyed if a sufficiently strong magnetic field is applied. A metal in this state has very unique magnetic properties that are unlike those at normal temperatures. A superconductor is often referred to as the perfect diamagnetic. Diamagnetic, ideally, are a class of materials that do not conserve magnetic flux, but expel it. A superconductor is classified as a perfect diamagnetic because by all measurable standards the magnetic flux within the material is zero. Electrons have a wave-like nature so an electron moving through a metal can be represented by a plane wave progressing in the same direction. A metal has a crystalline structure with the atoms lying on a repetitive lattice; a plane wave can pass through a perfectly periodic structure without being scattered into other directions. An electron is able to pass through a perfect crystal without any loss of momentum of its original direction. That is why it is important for superconductors to have very low impurities; any fault in the periodicity of the crystal will scatter the electron wave and introduce some resistance. This is called the residual resistance and it is independent of the temperature. Thermal vibrations also increase the resistance so when the temperature is lowered, the thermal vibrations of the atoms decrease and so the electrons are less frequently scattered. In short, the resistance of a metal is dependent on the purity of a metal and its temperature: metals with few impurities reach a superconducting state at low temperatures. The superconductivity state of a metal exists only in a certain range of temperature and field strength.

IT Applications and Groupware Essay

Groupware Technology uses software that collaborate the work of different groups. It is based on internal networks and centralized storage space. The purpose is to facilitate fast communication without physical contact. Groupware includes email, workflow, calendaring, instant messaging and conferencing. Implementation Strategies The three main strategies for effective implementation and use of groupware are as follows: Understanding the Organizational Requirements This is the most important part for implementation any technology or group in an organization. Different organizations require different groupware products as they have different requirements. (Hills) A groupware that is good for one organization might turn out to be a disaster for another. Therefore it is necessary to understand the requirements of the organization before implementing any new technology. This involves the study of underlying business processes and work flows, mapping them and then identifying gaps and areas which need improvement or need to be automated. The goals of the company, its organization structure and size are important factors in evaluating what is best for the company. Large companies with great number of employees require higher level of collaboration as compared to small companies and therefore need more complex technology. The communication structure within the organization is also an important factor. Some organizations follow a strict and formal stru cture of conversing while others rely on less formal way. Thus the communication style needs to be understood before implementing technology to automate it. Lastly the new technology must blend well with the existing systems. Most of the organization do not follow a sharing culture and people like to work independently and are reluctant to share information. Implementing Groupware technology in such an organization will not be effective as people would oppose any change that will be threat to their existing culture. The solution lies in first changing the organization culture and then implementing the new technology. The company should promote a collaborative culture that encourages people to work in teams and share their work and ideas. (Hills) Managing and Training People People are an important asset of any organization. If their needs and requirements are not satisfied then any change introduced in bound to fail.   Unless the technology is accepted by the users, any investment in that technology would be a complete failure. People usually oppose change because they like doing the things they have always been done. Therefore it is important to understand their concerns, problems and interactions before implementing the groupware technology. They need to be assured that the new technology is not to replace them but to make their work more efficient and fast. Employees most fear the loss of control and privacy as groupware makes everything available to everyone through a centralized system. These fears can be overcome by making people a part of implementation process and involving them as much as possible. Moreover people do not like to follow standard operating procedure and follow the more convenient methods. Thus the actual work practices need to be studied and incorporated in the groupware systems. (Hills) The success of any investment in technology depends on how readily it is accepted by the users. Therefore whenever a new technology is introduced the user must be trained to use it. They must be made to feel secure and assured that the technology is to improve their work. Organizations must hold training and interview sessions to cover all their needs and to involve them in the implementation process as much as possible. The purpose and benefits of the new groupware technology must be well communicated. 3. Using the Right Technology and Tools Once the organization and people requirements are well understood, the organization knows which technology is suitable for them. However other than the organizational structure and people, the technology infrastructure of the organization is also an important factor. There are four main factors to consider:  · Internal Network Structure The groupware technology is meant to provide a shared environment through collaboration and therefore require good understanding of the existing network technology. Network delays, User interface, audio/video quality, notifications and concurrency control are vital considerations since they all affect the user experience. (Brinck, 1998) If the existing Networks of the company are not up to the standard and face considerable delays and suffer from slow response time then implementing any new technology would do no good but will actually make things worse. Therefore organizations must upgrade their technology infrastructure including internal networks to utilize full benefit of the new technology.  · Collaborative tools One of the challenges in the collaborative environment is the tracking of shared documents. In a shared environment documents are used by multiple people and there exist multiple copies of the same document in different places. This makes hard to identify which the final version of the document. So Tracking and Version Control tools in groupware keep a record of all changes in a document and present the user with one final version. Features like Digital Signatures also help in tracking documents by storing information about who holds the document at what time and what changes were made. (Miller, 2005)  · Maintaining Privacy and Control Since collaborative systems allow sharing of information, thus Privacy and Security are the two major challenges faced by organizations implementing groupware. However some information is private and needs to be protected. The collaborative environment of groupware technology allows all information to be available to everyone at all time. This may lead to unauthorized access of information. One way to protect confidential information is to gives users control over what information they want to share. Also enforcing controls over what information a user can view saves private information to be seen by users who do not require it.   (Brinck , 1998)  · Consistency and Concurrency In groupware systems, one document is viewed by multiple users. Therefore it is important that consistency is maintained and all users view the same type of information. For example if one user has red color for a particular document and the other user has a blue color for the same document then this will create confusion. All users must be view the same data. To avoid this misunderstanding users must now what information is private and what information is shared. It is also important that users are provided customized view as all users don’t require everything. However customization requirements must not conflict with consistency. Every user must know how others are viewing the information. (Brinck, 1998) Concurrency is coordinating multiple tasks that are done at the same time. In a shared environment one document can be accessed by multiple users. This causes problems like one person accessing the document for all the time, unauthorized access and conflicting changes made by all users. To avoid such issues techniques like floor control, locking and merging is used. In this only one person can control over who accesses the document and for what time. The person who wants to access the document locks it so that other users can just view it without modifying. Similarly all users can edit the document during the time it is locked with them. In the end all the changes by different users are merged together so that the users have one final document at the end. (Brinck, 1998) Conclusion Technology infrastructure including the internal networks of the organization is important  issue that needs attention for any new technology implementation. However the social impact  cannot be ignored. It is highly required for successful implementation that the technology fulfills  the needs of users and is accepted by them.

Genetically Modified Organisms The Most Natural Or...

As an American, I have always been aware that my country does not have the most natural or healthy diet. We live in a country with 160,000 fast food restaurants and grocery stores filled with processed foods that can be quickly prepared for the convenience of the consumer. The food industry may make your daily meals and snacking easy and affordable; however, it is important to remember the nutritional value of the foods you are consuming and the affects they may have on your health. When eating non-organic food, whether from a restaurant or a store, remember that almost all of the food shares one ingredient; GMO s. GMO s, or Genetically Modified Organisms, are plants or animals whose cells have been genetically altered with genes from†¦show more content†¦An antifreeze gene can be added to crops so that unexpected cold cannot harm seedlings. By creating crops that can withstand drought, it makes it more convenient for farmers to grow crops in regions that usually aren’t suitable for specific plants. With the vast world hunger existing today, not everyone is getting the nutrition needed to survive; therefore, certain nutrients can be added to crops to help aid nutrient deficiencies. The benefits of genetic engineering may seem feasible; however, each can be disputed. These modified crops pose a risk on the environment and the health of people and animals. When you go into the supermarket, 90% of the foods around you are processed. Within those processed foods about 80% of them contain GM ingredients. In 2014, according to the United States Department of Agriculture (USDA), 94% of soybeans, 93% of corn, 96% of cotton, and 90% of sugar beets are genetically modified. Another study shows that 88% of canola oil is modified. Other produce includes sugarcane, potatoes, papaya, squash, beets, peas, vegetable oils, etc.The list of modified ingredients does not seem vast; however, these ingredients are found in thousands of processed foods such as baby formula, any sort of cake mix, sugar, cookies, potato chips, bread, pop tarts, Gatorade, cereal, candy, soda, juice, condiments, cheese, pasta and sauces, etc. Common food brands such as Chef Boyardee, Frito-Lay, Betty Crocker, Morningstar, Nestle, Heinz, Banquet,