bckground

3/01/2011

Application Software

Application software, also known as an application or an "app", is computer software designed to help the user to perform singular or multiple related specific tasks. It helps to solve problems in the real world. Examples include enterprise software, accounting software, office suites, graphics software, and media players.

Application software is contrasted with system software and middleware, which manage and integrate a computer's capabilities, but typically do not directly apply them in the performance of tasks that benefit the user. A simple, if imperfect, analogy in the world of hardware would be the relationship of an electric light bulb (an application) to an electric power generation plant (a system). The power plant merely generates electricity, not itself of any real use until harnessed to an application like the electric light that performs a service that benefits the user.


Terminology 

In information technology, an application is a computer program designed to help people perform an activity. An application thus differs from an operating system (which runs a computer), a utility (which performs maintenance or general-purpose chores), and a programming language (with which computer programs are created). Depending on the activity for which it was designed, an application can manipulate text, numbers, graphics, or a combination of these elements.

Application software classification

An application suite consists of multiple applications bundled together. They usually have related functions, features and user interfaces, and may be able to interact with each other, e.g. open each other's files. Business applications often come in suites, e.g. Microsoft Office, OpenOffice.org, and iWork, which bundle together a word processor, a spreadsheet, etc.; but suites exist for other purposes, e.g. graphics or music.

Enterprise software addresses the needs of organization processes and data flow, often in a large distributed environment. (Examples include financial systems, customer relationship management (CRM) systems, and supply-chain management software). Note that Departmental Software is a sub-type of Enterprise Software with a focus on smaller organizations or groups within a large organization. (Examples include Travel Expense Management and IT Helpdesk)

Educational software is related to content access software, but has the content and/or features adapted for use in by educators or students. For example, it may deliver evaluations (tests), track progress through material, or include collaborative capabilities.

Mobile applications run on hand-held devices such as mobile phones, personal digital assistants, and enterprise digital assistants: see mobile application development.

Product engineering software is used in developing hardware and software products. This includes computer aided design (CAD), computer aided engineering (CAE), computer language editing and compiling tools, Integrated Development Environments, and Application Programmer Interfaces. YUH ZEIT * A command-driven interface is one in which you type in commands to make the computer do something. You have to know the commands and what they do and they have to be typed correctly. DOS and UNIX are examples of command-driven interfaces.


Wireless Sensor Network (WSN)


A Wireless Sensor Network (WSN) consists of spatially distributed autonomous sensors to monitor physical or environmental conditions, such as temperaturesoundvibrationpressure, motion or pollutants and to cooperatively pass their data through the network to a main location. The more modern networks are bi-directional, enabling also to control the activity of the sensors.

The development of wireless sensor networks was motivated by military applications such as battlefield surveillance; today such networks are used in many industrial and consumer application, such as industrial process monitoring and control, machine health monitoring, environment and habitat monitoring, healthcare applications, home automation, and traffic control.

The WSN is built of "nodes" - from a few to several hundreds or even thousands, where each node is connected to one (or sometimes several) sensors. Each such sensor network node has typically several parts: a radio transceiver with an internal antenna or connection to an external antenna, a microcontroller, an electronic circuit for interfacing with the sensors and an energy source, usually a battery.

A sensor node might vary in size from that of a shoebox down to the size of a grain of dust, although functioning "motes" of genuine microscopic dimensions have yet to be created. The cost of sensor nodes is similarly variable, ranging from hundreds of dollars to a few pennies, depending on the complexity of the individual sensor nodes.

Size and cost constraints on sensor nodes result in corresponding constraints on resources such as energy, memory, computational speed and communications bandwidth. The topology of the WSNs can vary from a simple star network to an advanced multi-hop wireless mesh network. The propagation technique between the hops of the network can be routing or flooding.




Area monitoring

Area monitoring is a common application of WSNs. In area monitoring, the WSN is deployed over a region where some phenomenon is to be monitored. A military example is the use of sensors to detect enemy intrusion; a civilian example is the geo-fencing of gas or oil pipelines.  When the sensors detect the event being monitored (heat, pressure), the event is reported to one of the base stations, which then takes appropriate action (e.g., send a message on the internet or to a satellite). Similarly, wireless sensor networks can use a range of sensors to detect the presence of vehicles ranging from motorcycles to train cars.

Machine health monitoring

Wireless sensor networks have been developed for machinery condition-based maintenance (CBM)as they offer significant cost savings and enable new functionalities. In wired systems, the installation of enough sensors is often limited by the cost of wiring. Previously inaccessible locations, rotating machinery, hazardous or restricted areas, and mobile assets can now be reached with wireless sensors.

Air pollution monitoring

Wireless Sensor Networks have been deployed in several cities (Stockholm, London or Brisbane) to monitor the concentration of dangerous gases for citizens. The sensor nodes can control important parameters like CO, CO2, NO2 or CH4, which are generated by vehicles and industry, and have a severe impact in the human health. This way, the public institutions have a good tool to design plans to reduce pollution, improve the air quality and ensure the compliance with current legislation.

Agriculture

Using wireless sensor networks within the agricultural industry is increasingly common; using a wireless network frees the farmer from the maintenance of wiring in a difficult environment. Gravity feed water systems can be monitored using pressure transmitters to monitor water tank levels, pumps can be controlled using wireless I/O devices, and water use can be measured and wirelessly transmitted back to a central control center for billing. Irrigation automation enables more efficient water use and reduces waste.

The main characteristics of a WSN include:

*      Power consumption constrains for nodes using batteries or energy harvesting
*      Ability to cope with node failures
*      Mobility of nodes
*      Dynamic network topology
*      Communication failures
*      Heterogeneity of nodes
*      Scalability to large scale of deployment
*      Ability to withstand harsh environmental conditions
*      Easy of use
*      Unattended operation.

2/28/2011

Web Search Engine


A web search engine is designed to search for information on the World Wide Web and FTP servers. The search results are generally presented in a list of results and are often called hits. The information may consist of web pages, images, information and other types of files. Some search engines also mine data available in databases or open directories. Unlike web directories, which are maintained by human editors, search engines operate algorithmically or are a mixture of algorithmic and human input.

How web search engines work




Web search engines work by storing information about many web pages, which they retrieve from the html itself. These pages are retrieved by a Web crawler (sometimes also known as a spider) — an automated Web browser which follows every link on the site. Exclusions can be made by the use of robots. text. The contents of each page are then analyzed to determine how it should be indexed (for example, words are extracted from the titles, headings, or special fields called Meta tags).

WebCrawler is a meta search engine that blends the top search results from Google, Yahoo!, Bing Search (formerly MSN Search and Live Search), Ask.com,  About.com, MIVA, Look Smart and other popular search engines. WebCrawler also provides users the option to search for images, audio, video, news, yellow pages and white pages. WebCrawler is a registered trademark of Info Space, Inc.

WebCrawler was originally a separate search engine with its own database, and displayed advertising results in separate areas of the page. More recently it has been repositioned as a meta search engine, providing a composite of separately identified sponsored and non-sponsored search results from most of the popular search engines.



Some search engines, such as Google, store all or part of the source page (referred to as a cache) as well as information about the web pages, whereas others, such as AltaVista, store every word of every page they find. This cached page always holds the actual search text since it is the one that was actually indexed, so it can be very useful when the content of the current page has been updated and the search terms are no longer in it. 

When a user enters a query into a search engine (typically by using key words), the engine examines its index and provides a listing of best-matching web pages according to its criteria, usually with a short summary containing the document's title and sometimes parts of the text. 

Most search engines support the use of the Boolean operators AND, OR and NOT to further specify the search query. Boolean operators are for literal searches that allow the user to refine and extend the terms of the search. The engine looks for the words or phrases exactly as entered. Some search engines provide an advanced feature called proximity search which allows users to define the distance between keywords.

Most Web search engines are commercial ventures supported by advertising revenue and, as a result, some employ the practice of allowing advertisers to pay money to have their listings ranked higher in search results. Those search engines which do not accept money for their search engine results make money by running search related ads alongside the regular search engine results. The search engines make money every time someone clicks on one of these ads.

MARKET SHARE AND WARS

According to Net Market share. In December 2010, rankings the market share of web search engine, showed Google is 84.65%, Yahoo is 6.69%, Baidu is 3.39%, Bing is 3.29% and other is 1.98%. The Google's worldwide market share peaked at 86.3% in April, 2010. In the United States, Google held a 63.2% market share in May 2009, according to Nielsen Net Ratings. In the People's Republic of China, Baidu held a 61.6% market share for web search in July 2009.


2/27/2011

The less you know, the more you make.


"Salary Theorem" states that "Engineers and Scientists can never earn as much as Business Executives and Sales People." 

This theorem can now be supported by a mathematical equation based on the following two postulates:

1. Knowledge is Power.
2. Time is Money.

As every engineer knows:
Power = Work / Time

Since:
Knowledge = Power
Time = Money

It follows that:
Knowledge = Work/Money.

Solving for Money, we get:
Money = Work / Knowledge.

Thus, as Knowledge approaches zero, Money approaches infinity, regardless of the amount of work done.

Conclusion:
The less you know, the more you make. 

Why it's better to be a Woman!


1. We got off the Titanic first. 

2. We can be groupies. Male groupies are stalkers.

3. We can cry and get off speeding fines. 

4. We've never lusted after a cartoon character or the central female figure in a computer game.

5. Taxis stop for us. 

6. Men die earlier, so we get to cash in on the life insurance. Haha..

7. We don't look like a frog in a blender when dancing. 

8. Free drinks, free dinners, free movies ... (you get the point). 

9. We can hug our friends without wondering if she thinks we're lessy. 

10. New lipstick gives us a whole new lease on life. 

11. We can congratulate our team-mate without ever touching her. 

12. If we're dumb, some people will find it cute. 

13. We have the ability to dress ourselves. 

14. If we marry someone 20 years younger, we're aware that we look like an idiot. 

15. Our friends won't think we're weird if we ask whether there's spinach in our teeth. 

16. There are times when chocolate really can solve all your problems. 

17. We'll never regret piercing our ears. 

18. We can fully assess a person just by looking at their shoes.

19. We know which glass was ours by the lipstick mark. 

20. We have enough sense to realize that the easiest way to get out of being lost is to ask for directions. Huhu..
J