The Tech Storror

Data Transmission System Asynchronous Transmission: A data transmission system in which characters are transmitted from sender to receiver is called asynchronous transmission. In this method the sender does not require any primary storage medium for data transmission. Main features of asynchronous data transmission: (i) The sender does not require any primary storage device for data transmission. (ii) In this method of data transmission the sender can transmit the data at any time and the receiver can also transmit it. (iii) In this method of data transmission, the time between the transmission of one character and the transmission of another character may vary rather than be equal. (iv) Each character has a start bit at the beginning and end transmission is also called start/stop transmission. Advantages, Disadvantages and Uses of Asynchronous Data Transmission Advantages of asynchronous data transmission: (i) At any time the sender can send data and the receiver can receive it. (ii) ...

Modulation and Demodulation Modulation Audio or video waves received through transducers, known as signal webs, are difficult to transmit over long distances. High frequency carrier waves are used to transmit these signal waves over long distances as radio waves. The amplitude, frequency or phase of this carrier wave is changed according to the instantaneous value of the signal wave. Such changes are called modulation. In other words, mixing the signal with the carrier wave is called modulation. Modulation is mainly of two types, namely Amplitude Modulation (AM) and Frequency Modulation (FM). Use of Modulation: How far a real signal can be transmitted by a transmitter depends on two factors, namely -- (i) Transmitting Frequency (ii) Transmitter Power Modulation is used to send the signal farther. Different types of modulation methods: (1) Amplitude Modulation (AM) (ii) Frequency Modulation (FM) (iii) Pulse Modulation (PM) (iv) Frequency Shift Keying (FSK)  (v) Quadrature Amplitude ...

Wireless media: Wireless communication is a type of communication system that does not require any type of cable. In wireless communication, the sending device connects one computer to another computer or one device to another device through the radio web. Characteristics of Wireless Media: Wireless media do not use electrical or optical conductors or wires. In most cases, the Earth's atmosphere acts as the physical path for data transmission. Wireless systems are used when there are obstacles in the way of data transmission and installation of wired media is problematic. The three types of wireless media are -- (i) Radio Wave  (ii) Microwave   (ii) Infrared Radio wave: Network data is transmitted through radio transmission in the same way that signals are transmitted in radio. In this case every computer in the network can receive the signal sent by it. Radio wave frequencies are limited to 10 kHz to 1 GHz. The limited electromagnetic spectrum between 10 kilohertz and...

Transmission media: When a PC communicates or wants to communicate with another PC, it has to take the help of some transmission media. The most commonly used media in the network are twisted pair cable, coaxial cable, fiber optic cable. Nowadays, the use of optical fiber is increasing greatly. Radio wave, microwave and infrared technologies are prominent among wireless media. Among these mediums, optical fiber has the highest data transfer speed. The type of medium used in a network depends on the type and location of that network. The connection system for exchanging information between the sender and the remote receiving end is called a channel. The means or methods used to implement the channel are called media. such as-- (i) Cable or wire. (ii) Common telephone lines. (ii) Radio waves. (iv) Microwave. (v) Geo-satellite systems etc. Cable or Wire: Cable is an important medium in data communication. Cables are generally used for data transfer over short range networking such as LAN...

 Symptoms of a virus infected computer  A virus infected computer shows the following symptoms: (i) the computer takes longer than normal to start up; (ii) programs used on a daily basis run slower than normal; (iii) the program takes longer to load; (iv) accidentally deletes or hides any files; (v) takes longer than usual to store information; (vi) New software or hardware is not compatible and various messages are displayed (vii) abnormally reduced hard disk space; (viii) parts of the file are altered and marked abnormally; (ix) reduced printer speed in printing; (x) decrease or increase the size of command.com files; (xi) changes the size or name of files with an .EXE or COM extension; (xii) Overall system performance is impaired.

Software maintenance tools Software maintenance tools and system tools used in Windows operating system for software maintenance are backup, character map, disk clean-up, disk defragmentation, file and setting transfer wizard, schedule task, security center, system information and system restore. Below are descriptions of three commonly used tools (Disk Clean-up, Scan Disk or Check Disk, and Disk Defragmentation): (a) Disk clean-up: Many unnecessary files accumulate in the computer system at various times, such as temporary files, files downloaded from the Internet, files stored in Recycle Bin. All these files occupy the memory or space of the computer system. All these unnecessary file systems can be deleted using disk clean-up tool. The following unnecessary files can be deleted using disk clean-up tool. * Temporary Internet files * Downloaded program files * Deposit file in recycle bin * Temporary files (b) Scan Disk: If there is any error in the saved file, it can be corrected us...

Based on the interface, operating systems are divided into two categories, namely: (i) Text or character-based operating system (ii) Image-based operating system. Text or letter-based operating systems: In text-based operating systems, commands are executed by typing them in the command prompt according to their structure. Commands are written using letters, words, numbers, symbols, etc. To work in this system, the user needs to know the commands and syntax in advance and work by writing commands according to the syntax. Being color based this operating system is difficult and boring to work with. Commands have to be typed by keyboard only. A. Network, Internet system is not working. This system requires relatively little memory to operate, cannot run multiple programs simultaneously, supports only one user, and requires the use of a keyboard to move the cursor. No pictures, images or icons can be used in this command. Examples: MS-DOS, TOS, BOS, UNIX et cetera. Characteristics of tex...

Basic concepts of operating system The main purpose of the operating system is to-- • Creation of working environment: The operating system that creates a better working environment, the better and improved the operating system. • Coordinator: It coordinates between hardware and software. It acts as a coordinator between user tasks and all devices. • Automatic management: When a problem arises, it automatically understands what to do. If the appropriate solution is not provided, the operating system may automatically shut down the computer by itself. • Control of computer operations: The objective of the operating system is to control the speed of input/output operations by programs. • Memory management: helps the computer to work faster in stages by storing different files so that they can be found easily. this • Working based on priority: All the tasks that are directed to the computer are carried out based on priority. • Input/Output Management (I/O Management): It is the task o...

Register The register is a FF or memory element group, which works to store digital information together. It stores data in binary system. An FF can store one bit of digital data. The number of FFs needed to store a word depends on the number of bits in that word. For example, a group of 8 FFs is required to store a word of 8 bits. Thus, registers are groups of FFs or memory elements that work together to store digital information. In various digital systems, such as-  (i) Microprocessors of computers  (ii) Arithmetic and logic circuits.  Types of Registers: Registers are divided into different categories according to the type of work. Such as— (i) Temporary registers,  (ii) Flag registers,  (iii) General purpose registers are of 2 types based on providing inputs and outputs, namely—  (i) Serial and  (ii) Parallel. Four types according to data shifting or mode, namely : (i) SISO (ii) SIPO (iii) PISO (iv) PIPO Based on data shifting it is three types,...

Personal Information Manager: Personal information management is an important task for increasing office efficiency. People adopt various measures to manage this personal information. Eg: diary, notebook, electronic diary etc. People adopt these methods to perform the right task at the right time. Diaries are very important for managing many important information such as addresses, telephone numbers etc. Electronic diaries are now popular for personal information management. Various necessary information of daily life can be stored and used through this diary. Electronic diaries have a mechanism to signal the user for proper performance at specified times. Apart from that, many important information can be stored in the memory for future use through this diary. The work of personal information management can be done more easily through computers. A user's personal information can be neatly arranged through the large memory of the computer and various software. With the speed of co...

Introduction to Open Office: Open Source or the open software forum for all is publishing and promoting an integrated software called Open Office worldwide for free use by all. Open Office is a leading general office management software for word processing, spreadsheets, presentations, graphics, database etc., which increases office productivity manifold. This software can be downloaded and used completely free of charge with the facility of use on any type of computer in different languages. Current versions of Open Office software can easily import or export data or files used in other Office suites. Open Office has the facility to save documents or files in international open standard formats. This ensures the portability of OpenOffice files. Among the various programs in the OpenOffice.org suite are -- Their word processing program is called Writer.  And their spreadsheet analysis program is called Calc. The presentation program is Impress. The database program is Base. The pa...

Digital Office Management Basics and Elements: Basis of Digital Office Management The backbone of digital office management is the resource sharing network or connectivity through which various data and information can travel securely between each entity of the office. Office management can only be completed if information and flow can be ensured between each element of the office. A secure network is needed to ensure and secure office data flow. Networking refers to interconnected sharing of resources. Secure data sharing is considered the foundation of digital office management. To exchange this secure information, the network must also be secured. Components of Digital Office Management: The following 5 components or resources are required to create a modern office management system, namely (i) Hardware Resources (ii) Software Resources (iii) Data resources (iv) Network resources (v) Human resources. Human resource: The main component or resource of the office management system is...

Advantages of digital office management: (i) Constant communication of employees with the office: The main advantage of digital office management is that the office worker can always be connected to the office wherever he is. Any information can be provided at any time between each entity in the office. As a result, absence of a person from the office does not normally disrupt the functioning of the office. (ii) Non-inconsistency of data: In a traditional office environment, since the same information is written in multiple files, due to inconsistency, inconsistency or mismatch may be created between different data. For example, a regular customer's address has been changed in the sales section but not in the account section. There can be no data inconsistencies in digital office management. Because the authenticity and validity of the data is verified at various stages. (iii) Easier sharing and availability of data: There may be a need to exchange data between different department...

The word office is derived from the Latin word officium, whose Bengali term is office. Office in general sense is workplace, where people work. Office is needed to run the enterprise. Enterprise used to mean any business, venture or company, but now enterprise means large multinational corporations, universities, hospitals, research laboratories and government institutions, industries. And management means using information and communication technology and control systems to automate processes, so that minimal human intervention is required. Therefore, office management means the secretarial activities of the office through the application of information and communication technology (such as the preparation of necessary documents of the office, documentation and storage of documents, exchange of correspondence, internal and external communication, etc.) Also means done digitally. Automating routine office tasks is the main task of digital office management. Through digital office manag...

Electronic funds transfer is the transfer of money electronically through telephone and network. In this process, the amount of money is reconciled and modernized only through the account without exchanging the actual money between the accounts of different branches of the bank through electronic means. Banks use Automatic Teller Terminals or Machines (ATMs) for convenience and security in transactions. Bank cards with magnetic ink stripes are also used to perform bank transactions with data. Data is entered through a short key pad and inserted into the bank card terminal. Miniature video displays and printers are used for return signals. This card can be inputted in the bank or computer and can be withdrawn at any time of the day or night. The computer verifies the customer's signature, requiring no staff.

The World Wide Web is the largest repository of human knowledge in the world today. Through the Internet, people are constantly enriching this knowledge base and can use it for their various needs. But the unfortunate thing is that the benefits of using this vast wealth of knowledge around the world are limited to a lucky few. As of 2003, only 7% of the world's 6.4 billion people have access to the Internet. Rest of the population is deprived of this internet. The Internet will be fully worthwhile only when its benefits reach the majority of people in the world. The digital divide is a multifaceted problem. Hence experts from different perspectives have identified it in different ways. In this age of information and communication technology, the digital divide is defined based on the use of the Internet. In general, it can be said that the digital divide. A gap between an individual or a community created by access to the Internet, access to knowledge, and limited access to online ...

Today we will know the story of the birth of internet. How this internet came about, who made it etc.   The Internet is a wide area computer network spanning the globe. It is an international network made up of numerous LAN, MAN, ONE network connections. The number of networks connected to the Internet is currently in the thousands and the number of connected computers is over ten billion, and these numbers are growing rapidly. The early activities of the Internet began with the ARPANET. In 1969, the United States Department of Defense conducted a research project It connects four universities of the country through an experimental computer network. The name of this network is ARPANET. Initially, the use of this network was open to research institutes and universities. Later it spread in almost all areas. The term Internet was coined in 1982 with the invention of the TCP/IP protocol used to connect different networks. After that the number of internet users increased rapidly. The p...

The Information and Communication Technology Development Index was presented for the first time in the 2009 publication titled "Measuring the Information Society" by the International Telecom Union. Currently, various countries around the world are measuring information and communication technology using the Information and Communication Technology Development Index. It should be noted that information and communication technology National development is directly related to the development of communication technology and the following factors can be measured by the Information and Communication Technology Development Index, namely - (i) Advancement of information and communication technology for the development of a country (ii) Digital divide (iii) Stages and evolution of development of information and communication technology at different times (iv) Determining the role, scope and to-do of information and communication technology in the growth and development of the country...

Elements of Information and Communication Technology: The development of modern civilization is dependent on the application of information and communication technology. Computing, microelectronics, telecommunications, nanotechnology, bioinformatics, e-commerce, e-government etc. are closely related to information and communication technology. Database development technology, software development technology, network, printing and reprographic technology, information and storage technology are some of the elements required to use the different aspects. These elements are- (i) Hardware or machinery (ii) Software or Programs (iii) Related persons including humanware or computer users iv) Data or Information v) Network or communication media and (vi) Procedures etc. Types of information and communication technology: Information and communication technology can be divided into several categories. namely (i) Computing or information systems : All types of electronic data processing including...

Information technology, communication technology or telecommunications, consumer electronics (the radio, television, refrigerator, cassette recorder, DVD, Blu-ray disc, camcorder, camera etc. sub-industry of the electronics industry) and the entertainment or games industry were previously separate. All these sectors were developing according to some rules of their own. Their type of service, target group, market entrepreneurship, marketing etc. were different. For example - radio or television broadcasting, telephone conversation, online access to computers were all different and their services were also different. They were governed by separate policies, which were formulated by different policy makers. Data used in all these industries are text, audio, video, image, graphics, which can be expressed digitally. Digital convergence is the combination of different technologies to integrate and effectively manage them in one medium. Telecommunications, data processing and voice and image ...