MIDI for beginners :: Computer Science

MIDI for beginners Background The acronym MIDI stands for Musical Instrument Digital Interface. A Musical Instrument is a machine that makes sounds which humans have decided to call music. Digital means information that is encoded in numerical form, i.e. numbers, while Interface means a machine which facilitates communication between two or more systems. In practical terms, MIDI is a standard way for all sorts of modern musical equipment to talk to each other. This equipment commonly consists of things like keyboards, computer sequencers, synthesisers, and samplers, but it also includes mixers, tape recorders, effects generators, guitars, drum kits, wind instruments etc. The MIDI Standard was designed in the early 80's by a partnership between Roland and Sequential Circuits, two of the largest synthesiser manufactures of the time. This came about because of pressure from keyboard players, who wanted a universal interface standard for all their synthesisers to comply to. They were fed up with different synthesiser corporations using their own communications standard which were incompatible with those of other corporations. After the publication of the MIDI standard in 1984, other musical equipment manufactures quickly began to implement it in the designs of their products and MIDI became a world wide standard. A major advantage of MIDI over old analogue interface standards, such as CV (Control Voltage), is that it is possible to transfer up to sixteen channels of data down one cable, as opposed to CV's one channel per cable. Another major advantage of MIDI is that it enables computers equipped with MIDI to be used to write music and control musical equipment. This is done with programs called sequencers. They can give a very high degree of control over music, impossible through conventional means. Another advantage of MIDI is that it is now a world wide standard, insuring that practically all professional electronic music equipment will be compatible with it. Having sixteen channels to transfer MIDI data can also be a limitation when you want to use more than sixteen channels. However, this problem can be got around by using two or more midi interfaces each giving sixteen channels. Another limitation of MIDI is that you can not use it to transfer real time digital audio. MIDI information is transferred by sending a digital signal down a wire from one system to another. This digital data takes the form of binary numbers, physically transferred by sending zero volts for zero or off and plus five volts for one or on. Certain binary numbers convey certain types of information, for example a certain binary number will tell the device that a note on a keyboard has been pressed. This is called a note on event and the

Legal Aspects of Air Transportation

Legal Aspects of Air Transportation Kevinn A. Narvaez Y00285940 AWSC 3200 Air Transportation Prof. Ocasio Table of Contents IntroductionPage 3 Main EssayPage 4 ConclusionPage 6 ReferencesPage 7 Introduction: Air Transportation is one of the fastest growing sectors of the late 20th and early 21st centuries, as such, it is subject to an increasing legal requirements. Many legal requirements has to do with the financial side of the air transportation business, specifically financial and documentation matters. These legal requirements are usually decided via yearly ICAO and IATA meetings, but also via special conferences, such as the Chicago Conference and the Havana Conference, where major changes in international air transportation were made. In this project we will look at some of the different legal measures taken to ensure fair competition and standardize business practices in the international air transportation industry. We will also look at some of the international agreements regarding air transportation, and the effects that they have had on the industry. Main Essay: International air transportation is an example of a politically- dependent business. International agreements and disagreements affect were, how, when, and how frequently air carriers fly to international destinations. A clear example of this is the embargo against Cuba, flights from the United States to Cuba are extremely heavily regulated. In many other instances, politics have played an important role in determini ng international air transportation policy, and as such, international air transportation, is in a constant state of flux. A tragic example of a flight that was caught in the bad side of international disputes was Korean Airlines Flight 007, which was shot down over the former Soviet Union during September of 1983, a period during which relationships between East and West were at a straining point. Likewise, many laws affect the citizens of a particular nation, such as the Fly America Act, which obligates United States federal employees and their families to fly primarily on air carriers from the United States. This functions as a trade boon for American air carriers, virtually guaranteeing large revenues on international flights as well as domestic flights. 4 The Fly America Act was not the first legal action placed on international air transportation, we can go as far back the Chicago and Havana Conventions, and find evidence of legal actions imposed on air transportation. These legal actions are numerous, and include the â€Å"Nine Freedoms of the Air,† and the Montreal Convention, which establishes legal boundaries and requirements for law suits involving air carriers and passengers. Of course, the legal effects of air transportation have an effect on the economics of the business, when nations go to war, and declare blockades, airlines have to increase ticket prices to cover operational risks and other factors not planned for. With increased cost comes less reward, and eventually, the airline may have to shut down the route due to excessive costs. 5 Conclusion: The legal aspects of air transportation are numerous, and their effects are not only far-reaching, but powerful in their scope. As such, many airliners are subject to their rule, and have had to adjust their operations to compensate for these legal bindings. As we have seen, the legal affects don't just encompass laws and trade agreements, but also international politics and disputes. More often than not, air carriers prefer to not operate in areas that have been involved in international conflicts, for the sake of the passengers and the aircrew. The future of air transportation law is highly unpredictable, with nations making and breaking agreements every day. However, this does not exclude the airline industry from adapting to the changing legal climate as it has done in the past. Hopefully, in the future more agreements like the â€Å"Open Skies† act and the â€Å"Nine Freedoms of the Air† will cause the airline industry to flourish. 6 References: Air Transportation; Xunta de Galicia. Retrieved on 27/Nov/2009http://www. bygalicia. eu/en/keys_to_internationalisation/logistics_and_distribution/transport/air_transport/ International Civil Aviation, various, Retrieved on 27/Nov/2009 http://www. centennialofflight. gov/essay/Government_Role/Intl_Civil/POL19. htm Air Transport Law and Policy in the 1990's: Controlling the Boom, Aberson, Emile; Mendes de Leon, Pablo. Kluwer Academic Publishers. 1991 http://books. google. com. pr/books? id=yEvwGJnaZ-YC&pg=PA157&lpg=PA157&dq=legal+aspects+air+transport&source=bl&ots=QDO9UM67k4&sig=GjFZpfrImlsDED3UvuGuDUKHVZE&hl=en&ei=0nAWS4ecEs2ztgfMraj7BA&sa=X&oi=book_result&ct=result&resnum=3&ved=0CBIQ6AEwAjgy#v=onepage&q=legal%20aspects%20air%20transport&f=false Korean Air Lines Flight 007, various, retrieved on 27/Nov/2009 http://en. wikipedia. org/wiki/Korean_Air_Lines_Flight_007 Montreal Conference, ICAO. Retrieved on 28/Nov/2009 28/Nov. 2009http://www. jus. uio. no/lm/air. carriage. unification. convention. montreal. 1999/ 7

How to Make Pure Sand (Silicon Dioxide) in a Lab

Sand that you find on a beach consists of several minerals and organic matter. If you could separate out the impurities, you would have pure sand, which is silica or silicon dioxide. Here is how to prepare pure sand yourself in the lab. It is an easy project that only requires a few chemicals. Ingredients for Sand sodium silicate (make sodium silicate yourself)sodium bisulfatewater Make Pure Sand Mix together 5 ml sodium silicate solution and 5 ml water.In a separate container, use a glass stirrer to mix 3.5 grams sodium bisulfate into 10 mL of water. Keep stirring until the sodium bisulfate dissolves.Mix the two solutions together. The resulting gel that forms at the bottom of the liquid is orthosilicic acid.Place the orthosilicic acid into a heat-safe glass or porcelain dish and heat it over a burner flame for about 5 minutes. The orthosilicic acid dries to form silicon dioxide, SiO2, which is your pure sand. Sand is non-toxic, but it presents an inhalation hazard since the small particles could become trapped in your lungs if inhaled. Therefore, enjoy your sand, but dont play with it like you might with natural sand.