基于无人机的火灾检测系统设计与实现

针对传统森林火灾检测手段响应速度慢、效率低、误报率高等问题,设计了无人机搭载的由云台和相机组成的图像采集平台,通过火灾智能识别技术,实时识别监测火灾的发生,并达到了自动抵近侦察及实时态势感知的效果。在火灾智能识别算法方面,提出了improved-YOLOv3算法,通过在特征交互阶段增加yolo层,加强了网络对特征的融合度,从而增加了网络的检测能力。通过与性能相似的网络进行对比测试,验证了改进算法的有效性。测试结果表明,提出的算法检测准确率高、漏检率低、推理速度快,能够适用于实际火灾现场监测。     

海峡两岸非正规聚落火灾现状分析研究

全球城镇化进程显著提高了人民的物质生活水平和城市基础设施。然而,南北半球区域性经济发展不平衡导致全球依然有10亿人居住在生活水平较低和消防防治水平十分落后的非正规聚落中。近些年,国内外非正规聚落火灾频繁发生,但是有关中国大陆和台湾地区非正规聚落的火灾研究却处于初步阶段。为加深对海峡两岸非正规聚落火灾的理解和认识,通过中国大陆和台湾地区学者的合作开展了调查研究,简要概述了两岸非正规聚落的房屋类型和火灾危险性;并调研总结了两岸非正规聚落现有的火灾研究现状;根据两岸非正规聚落的成因和形态,简要总结了其火灾风险和消防问题。研究发现：中国大陆的非正规聚落主要分为棚户区、城中村、群租房、临时住所和部分少数民族传统村落等;台湾地区的非正规聚落主要分为违章使用和既有合法建筑两种形态：违章使用多见于违法分租、铁皮加盖与违法使用(农地自行盖房舍),既有合法建筑主要包括三合院、四合院、古迹历史建筑物和原住民部落等。两岸非正规聚落的房屋类型和火灾隐患具有共性,亟需开展更多的科学研究。     

室内火灾烟雾对微波衰减的影响研究

针对建筑室内火灾烟雾环境对微波信号的干扰问题,利用火灾标准实验间和微波实验装置,研究棉绳阴燃、聚氨酯明火等四种典型火灾烟雾对频率分别为600 MHz和2.7GHz微波衰减特性的影响规律。在有和无火灾烟雾环境下,对比分析入射波频率、烟雾浓度、烟雾类型对微波衰减的影响。实验结果表明,四种火灾烟雾对微波传播有明显衰减,且衰减量均随烟雾浓度的增加而增加,而衰减速率逐渐减小。频率以及不同特性类型的烟雾对微波衰减特性的规律不同。最后,计算并修正了室内火灾烟雾环境下微波衰减因子模型的衰减因子,提高了该模型在火灾烟雾环境下的适用性和准确性。     

Potential of weed species applied to remediation of soils contaminated with heavy metals

To screen out a series of ideal plants that can effectively remedy contaminated soils by heavy metals is the main groundwork of phytoremediation engineering and the first step of its commercial application on a large scale. In this study, accumulation and endurance of 45 weed species in ]6 families from an agricultural site were in situ examined by using the pot-culture field experiment, and the remediation potential of some weed species with high accumulation of heavy metals was assayed. The results showed that Solanum nigrum and Conyza canadensis can not only accumulate high concentration of Cd, but also strongly endure to single Cd and Cd-Pb-Cu-Zn combined pollution. Thus 2 weed species can be regarded as good hyperaccumulators for the remediation of Cd-contaminated soils. Although there were high Cd-accumulation in Artemigia selengensis, Znula britannica and Cephalanoplos setosum, their biomass was adversely affected due to action of heavy metals in the soils. If the problem of low endurance to heavy metals can be solved by a reinforcer, 3 weed species can be perhaps applied commercially.     

Vulnerability of land systems to fire: Interactions among humans,climate, the atmosphere,and ecosystems

Fires are critical elements in the Earth System, linking climate, humans, and vegetation. With 200–500 Mha burnt annually, fire disturbs a greater area over a wider variety of biomes than any other natural disturbance. Fire ignition, propagation, and impacts depend on the interactions among climate, vegetation structure, and land use on local to regional scales. Therefore, fires and their effects on terrestrial ecosystems are highly sensitive to global change. Fires can cause dramatic changes in the structure and functioning of ecosystems. They have significant impacts on the atmosphere and biogeochemical cycles. By contributing significantly to greenhouse gas (e.g., with the release of 1.7–4.1 Pg of carbon per year) and aerosol emissions, and modifying surface properties, they affect not only vegetation but also climate. Fires also modify the provision of a variety of ecosystem services such as carbon sequestration, soil fertility, grazing value, biodiversity, and tourism, and can hence trigger land use change. Fires must therefore be included in global and regional assessments of vulnerability to global change. Fundamental understanding of vulnerability of land systems to fire is required to advise management and policy. Assessing regional vulnerabilities resulting from biophysical and human consequences of changed fire regimes under global change scenarios requires an integrated approach. Here we present a generic conceptual framework for such integrated, multidisciplinary studies. The framework is structured around three interacting (partially nested) subsystems whose contribute to vulnerability. The first subsystem describes the controls on fire regimes (exposure). A first feedback subsystem links fire regimes to atmospheric and climate dynamics within the Earth System (sensitivity), while the second feedback subsystem links changes in fire regimes to changes in the provision of ecological services and to their consequences for human systems (adaptability). We then briefly illustrate how the framework can be applied to two regional cases with contrasting ecological and human context: boreal forests of northern America and African savannahs.     

城市的发展与火灾防治

随着经济的快速增长，火灾将会成为一个突出的灾害问题。作为经济发展中心的城市，火灾危险因素大大增加，因此，在城市的发展和改造过程中，应当同时抓好防火安全保障体系的建设，大力发展消防科技，并应加强防火安全教育，以便把火灾危害减少到最低限度     

隔油调节罐设计浅论

就隔油调节罐设置的目的、容积的确定、设置的位置、收油设施的设计、污油的加热排泥、排油的操作控制、消防措施及污油的输送等问题阐述了自己的看法。     

Developing a CFD heat transfer model for applying high expansion foam in an LNG spill

Liquefied natural gas (LNG) is widely used to cost-effectively store and transport natural gas. However, a spill of LNG can create a vapor cloud, which can potentially cause fire and explosion. High expansion (HEX) foam is recommended by the NFPA 11 to mitigate the vapor hazard and control LNG pool fire. In this study, the parameters that affect HEX foam performance were examined using lab-scale testing of foam temperature profile and computational fluid dynamics (CFD) modeling of heat transfer in vapor channels. A heat transfer model using ANSYS Fluent® was developed to estimate the minimum HEX foam height that allows the vapors from LNG spillage to disperse rapidly. We also performed a sensitivity analysis on the effect of the vaporization rate, the diameter of the vapor channel, and the heat transfer coefficient on the required minimum height of the HEX foam. It can be observed that at least 1.2 m of HEX foam in height are needed to achieve risk mitigation in a typical situation. The simulation results can be used not only for understanding the heat transfer mechanisms when applying HEX foam but also for suggesting to the LNG facility operator how much HEX foam they need for effective risk mitigation under different conditions.     

Investigation on the self-decomposition and explosion hazard of azo compounds

Azo compounds are self-reactive chemicals that violently produce flammable gases with heat release (i.e., an exothermic reaction). However, the explosion mechanism and ignition probability of azo compounds have not been clearly defined for storage or transportation. In this study, explosion scene analyses and various pyrolysis tests were performed to evaluate the thermal decomposition characteristics and explosion phenomena of azo compounds in a storage facility. The chemical debris collected from a fire scene was determined to be similar to the pyrolyzate of one of the tested azo compounds used by Py-GCMS. The minimum amounts of azo compounds, which could be ignited by self-decomposition heat, were calculated from the results of differential scanning calorimetrys and the heat transfer equation. The results were used to discuss a safety and response strategy for preventing the propagation of an explosion accident, namely a chemical backdraft.     

Topical scientific and practical issues of wildland fire problem

Problem of wildfires has not been resolved anywhere in the world. Mere increase of technical power does not lead to desirable results. Forests of developed countries burn as actively as those in Africa or in Russia. The main reasons of wildfire problem are as follows: (1) Constant wandering of dry seasons over the planet causing outbreaks of wildfires. (2) Unpredicted self-development of ordinary wildfires into awful fire disasters. (3) Difficulties in delivery and use of heavy machines on hardly accessible territories. (4) Absence of a perfect technique for economic evaluation of how effectively the wildfire control system works. (5) Absence of the system of payments encouraging wildfire fighters. To solve the problem of wildfires in Russia it is necessary to: (1) Create the Russian wildfire behaviour and fire effects prediction system on the basis of the developed classification of vegetation fuels and methods of their mapping as well as maximum utilization of forest inventory information and Geographic Information System (GIS). (2) Elaborate a technique of proper wildfire monitoring including estimation of vegetation damage. (3) Improve daily rating of regional fire danger. (4) Improve fire-preventive arrangement of the territory covered by vegetation, the main goal being creation of favourable conditions for active fire management. (5) Choose the main direction in elaboration of fire-fighting means and methods taking into account their universality, simplicity, reliability, etc. (6) Elaborate an improved technique for estimation of economic effectiveness of the wildfire control system. (7) Develop international cooperation of scientists and professionals in fire management.