Monday, March 24, 2008

Mobile Phone Radiation and Health

Since the beginning of mobile phones, apprehensions have been raised about the potential health forces from regular use. As mobile phone penetrations grew past fixed landline penetration levels in 1998 in Finland and from 1999 in Sweden, Denmark and Norway, the Scandinavian health authorities have run permanent long term studies of effects of mobile phone radiation effects to humans, and in particular children. Numerous studies have reported no significant relationship among mobile phone use and health. Studies from the Institute of Cancer Research, National Cancer Institute and researchers at the Danish Institute of Cancer Epidemiology in Copenhagen for model showed no link between mobile phone use and cancer. The Danish study only covered analog mobile phone tradition up through 1995, and subjects who started mobile phone tradition after 1995 were counted as non-users in the study. The health concerns have grown as mobile phone saturation rates throughout Europe reached 80%–90% levels earlier in this decade and prolonged experience studies have been carried out in almost all European countries again most reporting no effect, and the most alarming studies only coverage a possible effect. However, a study by the International Agency for Research on Cancer of 4,500 users found a borderline statistically important link between tumor frequency on the same side of the head as the mobile phone was used on and mobile phone usage.

Monday, March 17, 2008

The Telephone

The telephone is a telecommunications device that is used to transmit and receive sound (most commonly speech), generally two people conversing but occasionally three or more. It is one of the most universal household appliances in the world today. Most telephones operate through transmission of electric signals over a complex telephone network which allows almost any phone user to communicate with almost anyone.

Monday, March 10, 2008

Supercomputer

The term Super Computing was first used by New York World newspaper in 1920 to refer to the huge custom built tabulators IBM had made for Columbia University. A supercomputer is a computer that leads the world in terms of processing capacity, mostly speed of calculation, at the time of its introduction. Supercomputers introduced in the 1960s were designed mainly by Seymour Cray at Control Data Corporation (CDC), and led the market into the 1970s until Cray left to form his own company, Cray Research. He then took over the supercomputer market with his original designs, holding the top spot in supercomputing for 5 years (1985–1990). In the 1980s a large number of smaller competitors entered the market, in a parallel to the making of the minicomputer market a decade earlier, but many of these disappeared in the mid-1990s "supercomputer market crash". Today, supercomputers are characteristically one-of-a-kind custom designs produced by "traditional" companies such as IBM and HP, who had purchased many of the 1980s companies to gain their experience, although Cray Inc. still specializes in structure supercomputers.

The term supercomputer itself is rather fluid, and today's supercomputer tends to become tomorrow's also-ran. CDC's near the beginning machines were simply very fast single processors, some ten times the speed of the fastest machines offered by other companies. In the 1970s most supercomputers were dedicated to running a vector processor, and a lot of the newer players developed their own such processors at lower price points to enter the market. In the later 1980s and 1990s, attention turned from vector processors to enormous parallel processing systems with thousands of simple CPUs; some being off the shelf units and others being custom designs. Today, parallel designs are based on "off the shelf" RISC microprocessors, such as the PowerPC or PA-RISC, and most current supercomputers are now highly-tuned computer clusters using commodity processors combined with custom interconnects.

Tuesday, March 04, 2008

Natural Science

Natural sciences form the foundation for the applied sciences. Together, the natural and applied sciences are distinguished starting the social sciences on the one hand, and from the humanities, theology and the arts on the other. Though Mathematics, statistics, and computer science are not considered natural sciences, they supply many tools and frameworks used within the natural sciences.

Alongside this established usage, the phrase natural sciences is also sometimes used more narrowly to refer to its everyday usage, that is, related to natural history. In this sense "natural sciences" may refer to the biology and perhaps also the earth sciences, as illustrious from the physical sciences, including astronomy, physics, and chemistry.

Within the natural sciences, the word hard science is sometimes used to describe those sub-fields that rely on experimental, quantifiable data or the scientific method and focus on accuracy and objectivity. These generally include physics, chemistry and many of the sub-fields of biology. By contrast, soft science is often used to explain the scientific fields that are more reliant on qualitative research, including the social sciences.

There is some explore, collectivelly known as graphism thesis, that indicates that natural science relies on graphs more than soft sciences and mathematics do.