Tushar Enterprises

CCTV:-
Closed-circuit television camera
Closed-circuit television (CCTV) is the use of video cameras to transmit a signal to a specific place, on a limited set of monitors. It differs frombroadcast television in that the signal is not openly transmitted, though it may employ point to point (P2P), point to multipoint, or mesh wireless links. Though almost all video cameras fit this definition, the term is most often applied to those used for surveillance in areas that may need monitoring such as banks, casinos, airports, military installations, and convenience stores. Videotelephony is seldom called "CCTV" but the use of video in distance education, where it is an important tool, is often so called.[1][2]
In industrial plants, CCTV equipment may be used to observe parts of a process from a central control room, for example when the environment is not suitable for humans. CCTV systems may operate continuously or only as required to monitor a particular event. A more advanced form of CCTV, utilizing digital video recorders[3] (DVRs), provides recording for possibly many years, with a variety of quality and performance options and extra features (such as motion-detection and email alerts). More recently, decentralized IP cameras, some equipped with megapixel sensors, support recording directly to network-attached storage devices, or internal flash for completely stand-alone operation. Surveillance of the public using CCTV is particularly common in many areas around the world.
The analysis found that:
Surveillance systems were most effective in parking lots, where their use resulted in a 51% decrease in crime;
Public transportation areas saw a 23% decrease in crimes;
Systems in public settings were the least effective, with just a 7% decrease in crimes overall. When sorted by country, however, systems in the
Closed-circuit television (CCTV) cameras can produce images or recordings for surveillance[1] purposes, and can be either video cameras, or digital stills cameras.
Video cameras are either analogue or digital, which means that they work on the basis of sending analogue or digital signals to a storage device such as a video tape recorder or desktop computer or laptop computer.
Analogue
Can record straight to a video tape recorder which are able to record analogue signals as pictures. If the analogue signals are recorded to tape, then the tape must run at a very slow speed in order to operate continuously. This is because in order to allow a three hour tape to run for 24 hours, it must be set to run on a time lapse basis which is usually about four frames a second. In one second, the camera scene can change dramatically. A person for example can have walked a distance of 1 meter, and therefore if the distance is divided into four parts, i.e. four frames or "snapshots" in time, then each frame invariably looks like a blur, unless the subject keeps relatively still.
Analogue signals can also be converted into a digital signal to enable the recordings to be stored on a PC as digital recordings. In that case the analogue video camera must be plugged directly into a video capture card in the computer, and the card then converts the analogue signal to digital. These cards are relatively cheap, but inevitably the resulting digital signals are compressed 5:1 (MPEG compression) in order for the video recordings to be saved on a continuous basis.
Another way to store recordings on a non-analogue media is through the use of a digital video recorder (DVR). Such a device is similar in functionality to a PC with a capture card and appropriate video recording software. Unlike PCs, most DVRs designed for CCTV purposes are embedded devices that require less maintenance and simpler setup than a PC-based solution, for a medium to large number of analogue cameras.
Some DVRs also allow digital broadcasting of the video signal, thus acting like a network camera. If a device does allow broadcasting of the video, but does not record it, then it's called a video server. These devices effectively turn any analogue camera (or any analogue video signal) into a network TV.
Digital
These cameras do not require a video capture card because they work using a digital signal which can be saved directly to a computer. The signal is compressed 5:1, but DVD quality can be achieved with more compression (MPEG-2 is standard for DVD-video, and has a higher compression ratio than 5:1, with a slightly lower video quality than 5:1 at best, and is adjustable for the amount of space to be taken up versus the quality of picture needed or desired). The highest picture quality of DVD is only slightly lower than the quality of basic 5:1-compression DV.
Saving uncompressed digital recordings takes up an enormous amount of hard drive space, and a few hours of uncompressed video could quickly fill up a hard drive. Holiday uncompressed recordings may look fine but one could not run uncompressed quality recordings on a continuous basis. Motion detection is therefore sometimes used as a work around solution to record in uncompressed quality.
However, in any situation where standard-definition video cameras are used, the quality is going to be poor because the maximum pixel resolution of the image chips in most of these devices is 320,000 pixels (analogue quality is measured in TV lines but the results are the same); they generally capture horizontal and vertical fields of lines and blend them together to make a single frame; the maximum frame rate is normally 30 frames per second.
That said, multi-megapixel IP-CCTV cameras are coming on the market. Still quite expensive, but they can capture video images at resolutions of 1, 2, 3, 5 and even up to 11 Mpix. Unlike with analogue cameras, details such as number plates are easily readable. At 11 Mpix, forensic quality images are made where each hand on a person can be distinguished. Because of the much higher resolutions available with these types of cameras, they can be set up to cover a wide area where normally several analogue cameras would have been needed.
Network
IP cameras or network cameras are analogue or digital video cameras, plus an embedded video server having an IP address, capable of streaming the video (and sometimes, even audio).
Because network cameras are embedded devices, and do not need to output an analogue signal, resolutions higher than CCTV analogue cameras are possible. A typical analogue CCTV camera has a PAL (768×576 pixels) or NTSC (720×480 pixels), whereas network cameras may have VGA (640×480 pixels), SVGA (800×600 pixels) or quad-VGA (1280×960 pixels, also referred to as "megapixel") resolutions.
An analogue or digital camera connected to a video server acts as a network camera, but the image size is restricted to that of the video standard of the camera. However, optics (lenses and image sensors), not video resolution, are the components that determine the image quality.
Network cameras can be used for very cheap surveillance solutions (requiring one network camera, some Ethernet cabling, and one PC), or to replace entire CCTV installations (cameras become network cameras, tape recorders become DVRs, and CCTV monitors become computers with TFT screens and specialised software. Digital video manufacturers claim that turning CCTV installations into digital video installations is inherently better).
There continues to be much debate over the merits and price-for-performance of Network cameras as compared to analog cameras. Many in the CCTV industry claim that many analog cameras can outperform network cameras at a lower price.
Digital still cameras
These cameras can be purchased in any high street shop and can take excellent pictures in most situations.
The pixel resolution of the current models have easily reached 7 million pixels (7-mega pixels). Some point and shoot models like those produced by Canon or Nikon boast resolutions in excess of 10 million pixels.
At these resolutions, and with high shutter speeds like 1/125th of a second, it is possible to take jpg pictures on a continuous or motion detection basis that will capture not only anyone running past the camera scene, but even the faces of those driving past.
These cameras can be plugged into the USB port of any computer (most of them now have USB capability) and pictures can be taken of any camera scene. All that is necessary is for the camera to be mounted on a wall bracket and pointed in the desired direction.
Modern digital still cameras can take 500 kb snapshots in the space of 1 second, and these snapshots are then automatically downloaded by the camera software straight to the computer for storage as timed and dated JPEG files. The images themselves don't need to stay on the computer for long. If the computer is connected to the Internet, then the images can automatically be uploaded to any other computer anywhere in the world, as and when the pictures are taken.
The user does not need to lift a finger except to simply plug the camera in and point it in the desired direction. The direction could just as easily be the street outside a house, or the entrance to a bank or underground station.
Digital still cameras are now being made with in-built wireless connectivity, so that no USB cable is required; images are simply transmitted wirelessly through walls or ceilings to the computer.
EPABX:-
A business telephone system is a multiline telephone system typically used in business environments, encompassing systems ranging from small key systems to large-scale private branch exchanges.
A business telephone system differs from an installation of telephones with multiple lines in that the central office lines used are accessible in key systems from multiple telephone stations in the system, and that such a system often provides additional features related to call handling. Business telephone systems are often broadly classified into key systems, hybrid systems, and private branch exchanges.
A key system was originally distinguished from a private branch exchange (PBX) in that it did not require an operator or attendant at the switchboard to establish connections between the central office trunks and stations, or between stations. Technologically, private branch exchanges share lineage with central office telephone systems, and in larger or more complex systems, may rival a central office system in capacity and features. With a key system, a station user could control the connections directly using line buttons, which indicated the status of lines with built-in lamps.
CBX – computerized branch exchange
EPABX – electronic private automatic branch exchange
PABX – private automatic branch exchange
EPABX is an abbreviation that stands for Electronic Private Automatic Branch Exchange. It comes under the category of business phone systems which serve a business environment. Multi-line connections can be made through a single telephonic connection. It is an office equipment of immense use for telephonic connectivity with extensions of a single phone line. It can be rented from office equipment suppliers too.

Business Phone System for Office Communication
EPABX has proven to be of immense use in communicating within office, making routine work simpler. It can be defined as a switching system for calls that enables both internal as well as external switching functions in an organization. Typically up to 10,000 subscribers can be accommodated by a single EPABX system.
Range of Functions
EPABX as a business phone system possesses a versatile range of functions. The numerous tasks that can be performed by EPABX are listed below.
Auto Attendant
Automatic call distributor
Automated directory services (where callers can be routed to a given employee by keying or speaking the letters of the employee's name)
Automatic ring back
Call accounting
Call forwarding on absence
Call forwarding on busy
Call park
Call pick-up
Call transfer
Call waiting
Conference call
Custom greetings
Customized Abbreviated dialing (Speed Dialing)
Direct Inward Dialing
Direct Inward System Access (DISA) (the ability to access internal features from an outside telephone line)
Do Not Disturb (DND)
Follow-me
Music on hold
Night service
Shared message boxes (where a department can have a shared voicemail box)
Voice mail
Voice paging (PA system)
Components of EPABX
Internal switching network.
Microcontrollers and microcomputer for arbitrary data processing for control and the logic.
Logic cards, switching and control cards, power cards and related devices to facilitate operation.
Stations or telephone sets, sometimes called lines.
External Telco trunks that deliver signals to and from the EPABX.
Console or switchboard allows the operator to control incoming calls.
UPS, connecting wiring, cabinets and other housing materials.
The selection of an EPABX must be carefully done based on a detailed study of the traffic flow and needsof the office. They make communication within office easier and hence become a requisite as a business phone system in an office environment.

Fire alarm:
A fire alarm is a sounder. The sounders make a siren or a similar noise to let people know that there is a fire. Some companies that make fire alarms are Wheelock and Simplex. Sometimes, old-fashioned fire alarms are metal bells.
An alarm sounder is a device that will make a loud noise when the fire is discovered and the fire system set off with either a manual or an automatic system. The loud sound created will alert anyone at the building or site that there is a fire so they can escape safely. Many fire alarm systems also have flashing lights. These are important for deaf people who cannot hear the fire alarm.
Fire alarms are often used in schools and other places during