A membrane is a barrier that prevents entry of materials. Membranes can be permeable, which allows certain materials to go in and out of the barrier based on a variety of factors. Permeable Membrane in Biology In biology, a simple example of a permeable membrane is a cell wall. In both plant and animal cells, the cell wall is a permeable membrane that allows the passage of particular substances while preventing others. This is known as semi-permeability. Semi-permeability is found in plant and animal cells. The passage of substances is Read More

The term podcast was created in 1999 and depending on source, officially accepted in either 2003 or 2004. It is a combination of the word “iPod” and the word “broadcast.” An iPod is not required to enjoy podcasting, and podcasts can be played back on virtually all MP3-capable playback devices, or home computers, once they the Podcast stream has been downloaded in MP3 format. Podcasts are subscription-based like a magazine. And like TiVo, only the information that you’re interested in is delivered. You select what you’d like to listen to, Read More

A VCD (Video CD) is a video format or CODEC that has been used for video playback in DVD and VCD players since its adoption in 1993 by the video industry. The format allows 800 megabytes of VCD information to be stored on an 80 minute CD. The most recent version of the VCD format has a playback control (PBC) that is similar to that found on DVD menus. End-users do have the need arise; however, to convert the audio tracks on a VCD to MP3 format for use on Read More

One of the technology terms that most people have become accustomed to hearing either at work or while surfing the Internet is the database. The database used to be an extremely technical term, however with the rise of computer systems and information technology throughout our culture, the database has become a household term. A database is a structured collection of records or data that is stored in a computer system. In order for a database to be truly functional, it must not only store large amounts of records well, but Read More

Personal RFID tracking units are personal tracking units that depend on RFID or Radio Frequency Identification technology. Personal RFID tracking units allow users to identify and locate objects and individuals within a specific facility or area. Although personal RFID tracking units are not as popular or as common as other forms of personal tracking units and are rarely integrated into other devices such as GPS, they can be used for many of the same purposes. While personal RFID tracking units can be used in a wide range of applications, they Read More

In a doubly linked list, also called a two-way list, each node is divided into three parts: The first part, called the previous pointer field, contains the address of the preceding element in the list. The second part contains the information of the list. The third part, called the next pointer field, contains the address of the succeeding element in the list. In addition, two pointer variables, named head and tail, are used that contain the address of first element and the address of last element of the list. Implementation Read More

A set top box is an electronic device that is used to convert an externally received signal or transmission into a viewable format that can be displayed on a television/display device. Set top boxes have been used in some form since the 1950s. Its capabilities have significantly advanced over the past several decades. How Do Set Top Boxes Work? Set top boxes process digital information and are no longer simple signal converters. Currently, they can function as video game consoles, Digital Media Receivers, and media extenders. The most common set Read More

A QAM tuner (Quadrature Amplitude Modulation tuner) is a device that allows television sets to receive digital channels. QAM tuners are included in most modern television sets, although there are many that have not yet been upgraded to process digital channels. QAM tuners can be used in conjunction with a set top box or “cable box,” or by itself to receive unscrambled digital channels such as public access channels, basic channels, local broadcast channels, and cable radio channels. QAM tuners are similar to ATSC (Advanced Television Systems Committee) tuners, the Read More

The Error Loading Operating System error appears when an operating system fails to load properly. This error is localized to the Microsoft Windows XP operating system, so users of other operating systems should not face this problem. Essentially, the Error Loading Operating System error occurs at a point between the computer’s BIOS running checks on the system’s hardware and the actual launching of the operating system. This error is usually accompanied by a black screen and occurs directly after the installation of Windows XP. What Causes this Error? The Error Read More

Troubleshooting Exchange Server 2003 Installation A few reasons for an Exchange Server 2003 installation failing are listed here: The permissions being used for the installation are incorrect: To install Exchange Server 2003, the following permissions are needed: To initially run ForestPrep in a forest to update/extend the Active Directory schema – Member of the Schema Admins group and Enterprise Admins group. To run ForestPrep in a forest after the initial instance – Exchange Administrator permissions at the Exchange organization level. To run DomainPrep to prepare for Exchange Server 2003 installation Read More