Chelation-photoelectric concept for fire detection

An exploratory study has been made of the adsorption of incipient combustion gases on metal surfaces and organic metal chelate coated metal surfaces. Data obtained in this study suggest that a smoke or fire detection system could be based on the adsorption-photoelectric effects observed.     

Principles for fire detection

A fundamental approach has been undertaken to provide principles for fire detection. Basic relationships have been developed for heat and chemical compound detectors and applied to duct and enclosure environments.     

通信指挥车整体设计思路

按照中华人民共和国国家标准《消防通信指挥系统设计规范》,结合市域的实际情况,对大型通信指挥车在车辆、通信设备选型、结构设置、综合布线、空调、防雷设施等方面进行了深入细致的研究     

Photoacoustic gas detection for fire warning

A detector for measuring the gas concentration of carbon dioxide based on an infrared photoacoustic principle is presented. Many molecules and particles in the atmosphere cause extinction of an incident beam of infrared radiation due to absorption and scattering processes. The absorption occurs at wavelengths which are very specific for each molecule. In the miniaturized gas detector presented the ambient gas enters a small cell (approx. 1 cm³) via a diffusion membrane. The gas is irradiated with pulsed infrared light at the specific absorption wavelength for carbon dioxide. The absorption of the radiation energy by the gas molecules causes slight variations of the pressure inside the measuring cell which can be detected with a commercial microphone. The amplified and subsequently linearized microphone signal is proportional to the gas concentration present. The applicability of the photoacoustic principle for the detection of combustion gases is discussed.     

Photoacoustic gas detection for fire warning

A detector for measuring the gas concentration of carbon dioxide based on an infrared photoacoustic principle is presented. Many molecules and particles in the atmosphere cause extinction of an incident beam of infrared radiation due to absorption and scattering processes. The absorption occurs at wavelengths which are very specific for each molecule. In the miniaturized gas detector presented the ambient gas enters a small cell (approx. 1 cm³) via a diffusion membrane. The gas is irradiated with pulsed infrared light at the specific absorption wavelength for carbon dioxide. The absorption of the radiation energy by the gas molecules causes slight variations of the pressure inside the measuring cell which can be detected with a commercial microphone. The amplified and subsequently linearized microphone signal is proportional to the gas concentration present. The applicability of the photoacoustic principle for the detection of combustion gases is discussed.     

火灾探测性能综合评估试验平台设计

建筑的多功能、多用途使火灾探测器的应用环境变得日趋复杂，对产品的综合性能提出了更高的要求。针对特殊应用场所的特点，模拟和仿真探测器的应用环境，建立了一个集成平台对探测器的综合性能进行评估和测试。对总体方案和各部件单元的设计过程进行了论述。实际测试结果表明：系统达到预期设计目标，可以作为火灾仿真和探测器性能评估的专用工具，评估结果可以为产品改进和新产品开发提供帮助，也可以为工程评标和最终用户服务。     

谈我国社会和谐消防的构想

在分析当前消防工作现状的基础上,提出构建和谐消防的措施.     

Principles for a video fire detection system

The video fire detection system is based on the charge coupled devices camera and is introduced in this paper for its principles, fire criterion and system construction. The system is especially suitable to detect fires in large spaces and inhospitable environments.     

A design method for flaming fire detection

The scientific basis of a design method for the detection of flaming fires is reviewed. The equations required to calculate detector spacings are included and the selection of appropriate design input parameters is discussed. Limitations of the method and areas for further research are identified. The design method has been implemented and proposed for inclusion in NFPA Standard 72E-1984 as Appendix C by the 72E-M Committee. Center for Fire Safety Studies Worcester Polytechnic Institute     

Video image fire detection for shipboard use

The objective of this work was to evaluate the effectiveness of commercial video image fire detection systems for small, cluttered spaces as would be found on Navy ships. The primary goal was to establish an understanding of the performance sensitivity and limitations of the video image detection (VID) systems to various setup and environmental conditions that may occur onboard ship while exposed to a range of flaming and smoldering fire sources and potential nuisance alarm sources. The response of the VID systems was benchmarked against standard fire alarm systems using addressable ionization and photoelectric smoke detectors.     

Signal detection aspects in automatic fire detection

Automatic fire detectors can be considered as signal detectors for a special “signal-in-noise” detection problem. The paper uses the classical model for the measurable signal x(t) = s(t) + n(t) and gives an analysis of the signal component s(t), which is generated by the fire and which is to be detected. Using a general matched filter concept in combination with rather general properties of the fire signal component s(t), several forms of fire signal detectors can be developed which are optimum detectors in a rather general sense. These detectors are given as simple signal processing algorithms which can be realized by using a microprocessor or a special integrated electronic circuit. The efficiency of fire detectors depends very much on the behavior of the noise component n(t) which in the practical case of heat or smoke detection must be considered as highly self-correlated, in other words n(t) varies slowly with time compared with the fire signal component s(t). In this case it is nearly impossible to calculate the detector efficiency in advance for signal detection situations which may be interesting for practical cases.

In order to study the behavior and the efficiency of these detectors a Monte Carlo method has been used, and a measuring procedure has been established with suitable accuracy and in a way which covers the practical need.     

基于Web的火灾探测信息数据库系统

基于Web的火灾探测信息数据库系统是将标准试验火数据、应用环境数据、异常干扰事件数据、火灾烟雾颗粒形貌、粒径分布数据以及火灾气体成分数据等,以文字、图表、照片、视频等方式呈现在网络上,促进了消防领域相关研究的信息化.     

Engineering early warning fire detection

Fire detection system installations are not cut and dried. The author discusses the elements that must be considered when designing a detection system. Particular emphasis is placed on the ionization type of detector. Pyrotronics, Inc.     

A new test method for automatic fire detection devices

A new test method is proposed in which all automatic fire detectors, regardless of sensor type, would be subjected to a series of the same test fires. Note: Mr. Bright presented this paper at the 80th Annual Meeting of the National Fire Protection Association in Houston, Texas, May 1976.     

A trend-duration and gradient detector for automatic fire detection

Fire signals from sensors have a trend-duration characteristic, but such disturbance trends last only a short time. Step-shaped signals from fire sensors do not have a large trend value, although they may indicate a rapidly growing fire. Conventional trend algorithms cannot recognize the signal gradient. In this paper, a trend-duration and trend-gradient detector is proposed for automatic fire detection. The detector can distinguish fire signals from noise using a trend-duration algorithm. The fire smoke density (if smoke sensors are used) can be determined with the gradient algorithm. In order to indicate the level of the smoke density, fuzzy logic is applied to the gradient determination.     

融合显著性注意机制火灾探测与识别

基于人眼视觉注意机理,提出了一种融合显著性注意机制的火灾探测与识别方法,即眼见为实。通过模拟人眼视觉,融合显著性注意机制提取图中重要信息,剔除冗余数据,确定疑似火灾区域,然后使用多类型SVM 训练和学习。实验表明,提出的融合显著性注意机制结合多函数核SVM 的探测方法具有准确度高、稳定性好、总体性能优良等优点。