Library security reading room
The Library Guard Project
The alarm system of the books is located in the borrowing channels or the chief entrances/exits or other readers’ exits in the library.
Set the system detecting antennae and set the EM strips in the books at the same time. When the readers check out, the librarian degaussed the books by the deactivator to let the books pass the detector successfully. If someone checks out without the normal rules then the system could detect the books and alarm immediately to make he (she) recheck when he (she) passes the detecting antennae.
the technical principles of the electromagnetic wave alarm system
The basic principle is to detect if the objects have the EM strips by the transformations of the alternating magnetic field to prevent thefts. The electromagnetic identify technology is chief technology.
The electromagnetic technique detects by the alternating magnetic field produced by the low frequency from 10Hz to the 20KHz of the detecting antennae (transmitting antenna & receiving antenna). It detects the EM strips of the objects. The strips are PoMo alloy soft strips with cragged hysteresis loop. The polarities of the strips will be magnetized periodically over and over again when they were inside the alternating magnetic field of the transmitting antenna. The magnetic flux density B of the strips changes jumpily near the place where the external magnetic intensity H spans 0 (non-linear characteristic), then the harmonic wave would be produced whose frequency is the baseband of the transmitting antenna, and the receiving antenna will receive and process the wave and produce the alarm signal.
The working principle flow of the library alarm system
1. Set the EM strips inside the books.
2. Set the detectors at the library exit channels.
3. Degauss the books by the special deactivator after the normal checking.
4. The books without normal checking (that have the strips inside) will make the door detectors alarm and stop the readers.
The function of the electronic alarm system of the library
1. Preventing thefts. The system changed the old ways that the workers have to gaze at the readers or the workers have to take good care of the books in case that someone would steal the books. The system make the books protect themselves and solve the stealing problem totally. That could reduce the lost books and make the librarians work easier.
2. Alarm. The system could stop the readers stealing with a tough and polite way. It could avoid the disputes between persons and it could protect the profit of the library, meanwhile respecting the human rights. The system could warn and stop the thieves psychologically.
3. Improve the borrowing atmosphere. Many readers hate the old gazing way. The system could create a better atmosphere that readers could borrow books freely, and it could improve the relationship between the librarians and the readers which make the circumstance more comfortable.
4. Beautify the circumstance. The system is a high-tech product with beautiful appearance, it could beautify the circumstance when protecting the books. The system is a new trend for the libraries.
This project is composed by detecting channels, monitor, EM strips detectors, EM deactivator/reactivator and adhesive strips.
◆ The working scope of the monitor: the libraries of the colleges and universities, public libraries, Xinhua bookstores, record stores, medicine markets, cloth markets and other nonmetal markets.
◆ Please pay attention to the following problems before choosing electronic monitors:
1. The earth lines of the console must be earthed well.
2. All the metal conductors must be far away from the detecting doors at least a meter to avoid reducing the sensitivity and increasing misinformation.
3. If the exit distance is less than 1.5m you could use the single channel with two security doors and a console. The distance of each channel is about 800~1000mm (according to the length of the strips). The detecting distance could be 1200mm if using hard tag.
4. If the exit distance is more than 1.5m you could use double channels with three security doors and a console. And you could use three channels or four channels if the exit distance is wider.
5. There are two kinds of strips by their material: one is cobalt strip which is chiefly made of cobalt. They have better sensitivity consistency and the circumstance has little influence on the strips. They are too tough to break. But there are more expensive. The other one is iron strip which is chiefly made of iron. They are cheaper to popularize but they are fragile and easy to break. The circumstance could influence them easily so they should not be affixed inside the books or the objects directly by the gluewater because this can reduce the sensitivity of the iron strips seriously, so we must use the adhesive strips.
6. You could choose different security doors according to different taste. We have many kinds of security doors such as digital doors, digital environmental protecting & low power & low noise security doors, microcomputer security doors and software debugging security doors. According to the material we have wood painting doors, wood carved doors, resin doors, plastic doors, marble doors, transparent crystal acrylic plate doors and so on.
◆ the design for the libraries
1. Use composite strips with an EM deactivator/reactivator for lending libraries. Because the composite strips could be magnetized or be degaussed, the system would not alarm after the detecting and degaussing. To avoid readers breaking the strips, you could use another “strips detecting monitor” to detect if the strips are broken. The books could be magnetized first and then be detected on the monitor, if the strips are broken the monitor would alarm and vice versa in returning.
2. You could use the permanent strips for the books prohibited borrowing. The strips couldn’t be magnetized or degaussed, so we call them permanent strips.
Notes: the distance of the single channel is 75~100cm and the distance of the double channels is 150~200cm.
2. the introduction of the chief anti-theft products
The electromagnetic principle of the alarm system (recommended)
Detecting antenna: ES001 alarm system is a domestic high-grade anti-theft system at present.
ES001 the system in a makeup market
A. The system has a good stability and reliability with import digital managing technique and accessories. Working frequency: 2KHz.
B. The system has a powerful anti-jamming capability with import MPU technology and special anti-jamming circuit, it could avoid misinformation in the largest extent and it has a high degree of sensitivity with the minimal blind spots in China.
C. The power of the product is only 6w. It has a long life and a low power which is greatly lower than any other simulators.
D. Our company is the only one with multi-channel online in-phase technology in China and each channel could alarm.
E. It is a real digital product and progressive component composed by 13 integrate circuits.
F. The system is the first product designed with industrial concept. It has graceful and modern appearance with luxurious acryl glass surface. It could be set with soleplate or without soleplate.
G. The digital motherboard has a huge anti-jamming power and it only has a little influence on the computer monitors.
H. It could avoid misinformation in the largest extent with the total digital inner intermodulation technology.
I. The system will turn off the receiving circuitries automatically when receiving interference signals and it will turn on and come back to the normal power-on status automatically after the interference. (Improve the anti-jamming power.)
J. The system with memorizing running parameter makes long-distance debugging easier and makes operation & maintenance easier.
The EM strips:
According to the sorts we have cobalt strips and iron strips.
According to the functions we have permanent strips and composite strips.
1. Permanent strips that couldn’t be magnetized or degaussed.
The magnetism of the strips exists forever and they couldn’t be decoded. They are cheaper. They have high alarm rates and they could be hided easily. And we also have the double-sided adhesive strips that make the operation easier.
2. Composite strips that could be magnetized or degaussed.
They could be decoded but have a little higher price than permanent ones. And we also have the double adhesive strips that make the operation easier. Length: 40, 50, 60, 80, 100, 120, 160 (mm).
According to the appearance we have permanent naked strips, adhesive strips and barcode adhesive strips.deactivator/reactivator
This machine is matched just for the composite strip tags. It could only be useful when using composite strip tags.
It is the first decoding machine with infrared ray opposite sending technology in China. It only works when objects being decoded in the degaussing status, which could prolong the using time efficiently.
EM Strips Detector
The detectors are match products of the digital monitor system and they are mainly used to detect if the books (objects) have strip tags inside or mainly used to detect the strips sensitivity of the returning books or detect if the tags are still there. Their simulated skin veneer makes them top-grade and beautiful. They are stable, low power consumption, easy operated and so on, and they are so small that you could put them anywhere