The rapid development of microelectronics technology, detection sensor technology, communication and networking technologies has led to new changes in the field of urban fire detection and fire communication technology. Its main features are reflected in the advancement of fire detection and alarm time, the improvement of the reliability of fire detection alarms, the detection and alarm of fires in special places, the networking of fire detection and alarm systems, the intelligentization of fire-fighting linkage control, and the fire-fighting communications network technology and computer alarms. Command management. This article discusses the status quo of the development of urban fire detection alarms and fire communication technologies and the main problems. It also proposes new concepts such as fire forecasting and multi-information fire detection and sensing.
The new technology of urban fire detection, alarm and fire communication is a science that studies and solves the problem of fire after impending fire and fire. With the minimum cost, to achieve a reliable fire detection and alarm, and can minimize the fire damage, is an important performance indicators and continuous research difficulties in the pursuit of fire detection and alarm. To this end, people have studied urban fire detection and fire communication technologies through various channels. It is a comprehensive application technology involving various disciplines such as optics, electronics, sensing technology, information processing technology, control theory, logic, network science, computer technology, and combustion theory.
Advancement of fire detection and alarm time Some special important units and places such as computer centers, power dispatching command centers, post and telecommunications hubs, graphic and file information centers, semiconductor production workshops, nuclear power plants, etc., play a role in national economic and social production and life. Important role. Various electrical and electronic equipments and instruments in these places are highly concentrated and in long-term operation. There are many hidden fire hazards caused by overload, overheating, and short circuit of electrical equipment. Once a fire occurs, it will cause major economic losses to the country and give society Bring a major impact; in the event of a fire or explosion in a flammable or explosive location, it will be difficult to save in time. Given the importance and particularity of these places, the common types of temperature and smoke detection and alarm systems are no longer sufficient, and super-early fire detection and warning techniques must be used.
Some developed countries attach great importance to the research and product development of ultra-early fire detection and alarm technology. As early as the 1980s, Japan, the United States, the United Kingdom, Switzerland, Germany, Australia, and other countries have started technical research and product development in this field. At present, research and development of laser-type high-sensitivity smoke detectors and aspirators High-sensitivity fire detection alarm system and gas fire detection alarm system and other ultra-early fire detection and alarm products. These systems use the principle of laser particle counting and laser scattering to monitor the protected space, and determine whether or not a fire can occur with the increase in the particle volume per unit volume. The potential fire risk can be identified within hours or days before the fire occurs. To achieve ultra-early fire alarms. Compared with the common smoke detection and alarm system, the detection sensitivity of this system is improved by two orders of magnitude or more. However, at present, this technology is limited to the detection of smoke particles, and is still limited in application environment by application.
The use of gas and gas components in the detection of fire products in the early stages of the fire or the elements that constitute the fire detection technology is also another promising aspect of ultra-early fire detection. Experts believe that while researching the ultra-early-fire detection technology, fire detection alarms are divided into two phases: fire detection and fire prediction. New processing methods and concepts are explored. Using new concept guidance techniques will promote super early Development of fire detection technology.
Fire detection, fire detection and special sensor technology in special places New technology in flammable and explosive places Once an explosion occurs, the spread of fire is extremely fast and difficult to control. People have specially developed and developed a method to detect the concentration of combustible gas prior to a fire and explosion accident. Linear fire detection and warning systems for fire and explosion hazards. It adopts the optical principle and utilizes the difference in the spectral characteristics of different gases to detect the gas concentration. It fundamentally solves the problems of poor stability and short life of point-type combustible gas sensor elements. When used for large-area combustible gas detection and alarm, the performance price is compared. High, its principle can also be expanded to monitor the leakage of gas in other places.
However, the current special site fire detection alarm is still limited to a fixed form of research, and the related research on the prediction and detection of mobile dangerous goods and chemical disaster accidents is still at a blank stage.
The improvement of the reliability of the fire detection and alarm system The improvement of the reliability of the fire detection and alarm system is first reflected in the use of intelligent technologies to process the fire information provided by the sensors. People use multiple fire detection algorithms and composite multi-sensing sensing methods to provide more complete and reliable information for judging fires.
(I) Update of fire detector function One of the most important features of modern fire detectors is that the decision function and decision-making power are not only separated from the concept, but have also been implemented separately in practical applications. The early decision function and the determination decision were combined into one, which was realized by the sensor device provided in the detector, so that the processing problem was rigid and susceptible to interference. The judgment function and judgment decision power of modern fire detection sensors are controlled by software, which can filter out interferences, identify true and false fires, improve the reliability of the system, and realize intelligent determination of fires.
In addition, high-tech such as fuzzy logic and neural networks are used to distinguish fires, and it can also greatly improve the reliability of fire detection. Some fire-fighting linkage control devices and even control modules also begin to have intelligent functions. The discriminant function is further subdivided and two-level (or multi-level) discrimination is implemented to improve the performance and reliability of the fire detection and alarm system.
(II) Adoption of multiple information technologies Early fire detectors responded to fire information by outputting information of '0' or '1', that is, switching quantity. Other information only reflected whether the switch was normal or not and whether it could operate. While modern fire detectors monitor the fire process, some detectors essentially only act as sensors. Therefore, the amount of fire information increased significantly. On the other hand, fire information provided by various single sensors is mixed with non-fire information, which makes it difficult to distinguish fires from fire information provided by sensors. People began to study sensors based on new detection principles (such as gas sensors, etc.) and The composite detector monitors the multi-parameters of the fire process and is equipped with intelligent discrimination technology to achieve the purpose of reducing false alarms and improving reliability.
The identification of subtle features is also a way to identify fires from the perspective of providing information. The use of a single-chip microcomputer intelligent fire detector can break the passive situation in which the sample is controlled by the controller and actively acquire the very important information that is important for identifying true and false fire parameters.
Assessment of fire detection and alarm system Since the 1990s, the industrialization of fire detection and alarming in China has developed rapidly. There are more than 100 companies engaged in the production of fire detection and alarm products, and the annual production value reaches several billion yuan, which has become a high-tech industry in China. One of the components of foreign products has also entered the Chinese market. In China, about 2 million new fire detectors are installed in buildings each year, and about 80% of them are intelligent fire detection and alarm systems with fire detection algorithms. Because such systems rely on detection algorithms to determine the fire, the effectiveness of the fire detection algorithm becomes the key to determine the system performance. Under the existing technical conditions, it is still difficult to estimate and test the performance of fire detection algorithms for such products under complex and variable environmental conditions and after long-term operation. Only the detection methods of ordinary fire detection and alarm systems can be used to achieve high intelligence. The inspection of fire detection and alarm products has restricted its effectiveness.
At present, the mainstream products of China's fire detection and alarm system are intelligent fire detection and alarm products. Intelligent fire detection algorithms based on fuzzy logic and artificial neural network technology are gradually being applied in fire detection and alarm systems. The correction and improvement of algorithms and verification of the validity of algorithms all require the detection of fires.
However, the assessment technology of fire detection algorithms is a complex system engineering. Due to many reasons such as technical force, capital investment, and research and development cycle, the country has not carried out this research work scientifically and systematically. China's fire detection and alarm industry product and quality inspection technology has also affected the improvement of China's fire detection and alarm product technology and related product market competitiveness.
Networking of fire detection and alarm systems Networked fire detection and alarm systems refer to the application of computer data communication technologies to fire detection and alarm systems, and exchange of network protocols between controllers or between detectors, between systems and between systems. Data information, to achieve automatic fire alarm system level function set, remote data call management, automatic alarm, network monitoring and network communications services and other functions. Networking is the direction of the development of automatic fire alarm systems. With it, it can solve the problems of large-scale, super-large fire control projects with many control points and automatic alarms.
In order to effectively manage the fire detection and alarm system and give full play to its role, it is very important to implement network monitoring and management of the fire detection and alarm system. Such products and technologies have matured and are applied in practical projects with good results. However, at present, the communication protocols of fire detection and alarm systems of various manufacturers are various and independent, and there is no uniform format, which is not conducive to the development of fire detection and alarm systems. Therefore, with the development of the network of fire detection and alarm systems, network protocols will become one of the hot spots of concern.
Fire Communications Computer Management Fire communications are an important part of the urban public infrastructure and social security system. The fire communication command system in China is based on the actual situation in China. It uses computer application technology to link the main technologies and equipment of the fire command center, fire station, fire scene, and security inspection unit to the four links. The fire communication command system adopts a method of receiving fire alarms in a centralized manner and directly delivering tasks. It replaces ordinary telephone alarm methods, adds computer-assisted decision-making and scientific management, and shortens the response time of invoking fire extinguishing plans, determining driving directions and other fire fighting command information. , to make fire acceptance procedurally and standardized.
The system receives the fire automatic alarm signal through the monitoring device, can display the caller's calling number, user name, address and other related information in real time, quickly determine the fire site through various ways, and provide the geographical map and the best driving route of the misfire site in time. Such as, at the same time corresponding to the display of the fire station near the fire station and other related fire fighting capabilities. The system can also automatically and manually compile joint dispatching plans based on fire categories, fire levels, fire fighting power, weather and geography environment, fire fighting and rescue tactical technology and other relevant factors, and deliver outbound orders to each fire station to greatly enhance the effectiveness of fire fighting operations.
Fire communication network technology Fire communication network technology is an important foundation for realizing fire communication. In the 70s and 80s of the last century, fire communication was mainly composed of wireless communication equipment as a fire communication network. Modern fire communication was an integrated fire communication network consisting of a combination of wired and wireless devices and computers, and its contents and complexity were enormous. Variety.
Some developed countries adopt geographic information technology, database technology, digital program control technology, digital signal processing technology, automatic control technology, satellite positioning technology, image transmission technology, voice digital processing technology, expert system network technology, etc. in the construction of fire communication command system. Modern high-tech, improve the system's scientific automation. The urban fire communication command system currently being developed in China is also basically equipped with the above technical functions or has corresponding interfaces, so as to gradually form an urban disaster prevention and disaster relief integrated system.
The application of simulation technology as an emerging application technology has played a role in many important fields. Fire-fighting operations command simulation training and the use of simulation technology to study, analyze, and formulate fire-fighting operational plans are very important for training combatants with modern fire-fighting operational qualities and improving fire-fighting efficiency. At present, the simulation system suitable for fire protection is still a blank in the world. China should carry out such research by combining the relevant human, material, and financial resources with the national conditions.
Release date:2012/2/27 14:48:58
Submersible Deep Well Pump
Deep Well Pump,Submersible Multistage Pump,Submersible Pump
Pump & Vacuum Equipment CO.,Ltd , http://www.nssubmersiblepumps.com