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Sliding Mode Predictive Control of Main Steam Pressure in Coal-fired Power Plant Boiler 被引量:4
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作者 史元浩 王景成 章云锋 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2012年第6期1107-1112,共6页
Since the combustion system of coal-fired boiler in thermal power plant is characterized as time varying, strongly coupled, and nonlinear, it is hard to achieve a satisfactory performance by the conventional proportio... Since the combustion system of coal-fired boiler in thermal power plant is characterized as time varying, strongly coupled, and nonlinear, it is hard to achieve a satisfactory performance by the conventional proportional integral derivative (PID) control scheme. For the characteristics of the main steam pressure in coal-fired power plant boiler, the sliding mode control system with Smith predictive structure is proposed to look for performance and robustness improvement. First, internal model control (IMC) and Smith predictor (SP) is used to deal with the time delay, and sliding mode controller (SMCr) is designed to overcome the model mismatch. Simulation results show the effectiveness of the proposed controller compared with conventional ones. 展开更多
关键词 coal fired power plant boiler combustion system main steam pressure sliding mode control Smith predictor internal model control
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Fire Blight Disease Caused by Erwinia amylovora on Rosaceae Plants in Kyrgyzstan and Biological Agents to Control This Disease 被引量:15
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作者 Tinatin Doolotkeldieva Saykal Bobusheva 《Advances in Microbiology》 2016年第11期831-851,共21页
Erwinia amylovora species were isolated from the blossoms, exudates, infected fruits, leaves and bent branches of diseased apple, pear and hawthorn trees, selected in the Chy, Osh and Jalal Abad regions. Biochemical a... Erwinia amylovora species were isolated from the blossoms, exudates, infected fruits, leaves and bent branches of diseased apple, pear and hawthorn trees, selected in the Chy, Osh and Jalal Abad regions. Biochemical and pathogenicity tests, alongside PCR analyses, were conducted to identify the local isolates of Erwinia amylovora. The alternative antagonistic microorganisms which combat bacterium E. amylovora were tested within in vitro and in vivo conditions. The results revealed the ability of Streptomyces antagonistic bacteria to decrease fire blight severity on pear and apple trees during the first stage of the fire blight disease in leaf tissues. Streptomyces strain C1-4 suppressed E. amylovora disease symptoms in the leaf tissues and excised apple and pear shoots. The incidence of fire blight on leaves was reduced by about 70% with two applications of bacterial antagonists. Further studies at different locations in Kyrgyzstan, using large scale application, would allow for stronger recommendations to be made, including studies and recommendations on their ability to prevent disease and to use them as main components in an integrated pest management program. 展开更多
关键词 Biological control Agents Fire Blight Erwinia amylovora Antagonistic Bacteria
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Developing Environment of Hierarchical and Distributed Real-Time Fire-Control Network 被引量:1
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作者 He Jianhua(Northwestern Polytechnical University, Xi’an 710072, P. R. China)(This project was supported by the Astronautics Foundation.) 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 1998年第4期1-7,共7页
This paper introduces a hierarchical real-time environment for developing ship-bornefire-control system. Advanced computer networks are used to simulate the system with the requiredengagement scenario, including own-s... This paper introduces a hierarchical real-time environment for developing ship-bornefire-control system. Advanced computer networks are used to simulate the system with the requiredengagement scenario, including own-ship and parameters, and data processing and transmission,mission calculation, graphical supervision and gunnery ballistics outputting. The simulation systemis able to receive instruction from, or send information to the command-control center. Furthermore,the system can also be used to compare various designed schemes and analyze the accuracy andeffectiveness of the system. 展开更多
关键词 Distributed network Fire-control RS-485 communication Software environment
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Intelligent Design and Implementation of Missile Fire Control System
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作者 谢春思 王敏庆 +2 位作者 李卫海 刘喜作 金良安 《Defence Technology(防务技术)》 SCIE EI CAS 2006年第4期297-300,共4页
Missile fire control system is the core of ship-based missile weapon system, whose safeguard level has direct relation with the attack ability of naval vessels. After a long period of deep investigation and research, ... Missile fire control system is the core of ship-based missile weapon system, whose safeguard level has direct relation with the attack ability of naval vessels. After a long period of deep investigation and research, it was found that, in one missile fire control system, there are such problems as single safeguard system, low ratio of cost to efficiency, etc. By adopting intelligent control techniques and many measures to multiple securities, the new type of assistant system is designed, some difficult problems are solved, such as fixed project channel and unitary means of missiles, which can make the equipment carry out combat mission reliably and continuously. 展开更多
关键词 海基导弹武器系统 火力控制系统 智能设计 智能控制 费效比
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Tank Fire Control Systems Accuracy Assignment Based on Fuzzy Comprehensive Judgment Method
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作者 刘文果 陈杰 窦丽华 《Journal of Beijing Institute of Technology》 EI CAS 2003年第4期347-351,共5页
A method of accuracy assignment based on fuzzy comprehensive judgment method (FCJM) in tank fire control system is proposed. From the flowing route of the error sources and their respective correlative signals, the tr... A method of accuracy assignment based on fuzzy comprehensive judgment method (FCJM) in tank fire control system is proposed. From the flowing route of the error sources and their respective correlative signals, the transfer functions of several sources are analysed by means of mathematic simulation, and FCJM is applied to obtain the cost comprehensive factor for each part of system, combining its error sensitivity factor the mathematical model is built to solve the accuracy assignment problem. Simulation result shows the proposed method can help designer of tank fire control system work out an optimal system more efficiently and more economically. 展开更多
关键词 fire control system accuracy assignment error sources fuzzy comprehensive judgment
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Simulation on an optimal combustion control strategy for 3-D temperature distributions in tangentially pc-fired utility boiler furnaces
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作者 WANGXi-fen ZHOUHuai-chun 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2005年第2期305-308,共4页
The control of 3-D temperature distribution in a utility boiler furnace is essential for the safe, economic and clean operation of pc-fired furnace with multi-burner system. The development of the visualization of 3-... The control of 3-D temperature distribution in a utility boiler furnace is essential for the safe, economic and clean operation of pc-fired furnace with multi-burner system. The development of the visualization of 3-D temperature distributions in pc-fired furnaces makes it possible for a new combustion control strategy directly with the furnace temperature as its goal to improve the control quality for the combustion processes. Studied in this paper is such a new strategy that the whole furnace is divided into several parts in the vertical direction, and the average temperature and its bias from the center in every cross section can be extracted from the visualization results of the 3-D temperature distributions. In the simulation stage, a computational fluid dynamics(CFD) code served to calculate the 3-D temperature distributions in a furnace, then a linear model was set up to relate the features of the temperature distributions with the input of the combustion processes, such as the flow rates of fuel and air fed into the furnaces through all the burners. The adaptive genetic algorithm was adopted to find the optimal combination of the whole input parameters which ensure to form an optimal 3-D temperature field in the furnace desired for the operation of boiler. Simulation results showed that the strategy could soon find the factors making the temperature distribution apart from the optimal state and give correct adjusting suggestions. 展开更多
关键词 tangentially-fired boilers combustion control three-dimensional temperature distributions adaptive genetic algorithm
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Accuracy Assignment Study of Tank Fire Control System Based on Value Analysis Method
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作者 窦丽华 张佳 陈杰 《Journal of Beijing Institute of Technology》 EI CAS 2006年第4期411-415,共5页
A method of accuracy assignment based on value analysis method (VAM) in tank fire control system (TFCS) is proposed. From the analysis of primary error sources and their error transfer relationships, the mathemati... A method of accuracy assignment based on value analysis method (VAM) in tank fire control system (TFCS) is proposed. From the analysis of primary error sources and their error transfer relationships, the mathematical model is built on the basis of VAM to solve the accuracy assignment problem. Simulation results show the validation and feasibility of the proposed method. It can help designer of tank fire control system work out an optimal system more efficiently and more economically. 展开更多
关键词 tank fire control system(TFCS) accuracy assignment value analysis method(VAM)
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Control of ecological environmental pollution in fire accident
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作者 YANG Jie 《Ecological Economy》 2017年第3期234-240,共7页
The fire causes water pollution, air pollution and toxic gas pollution to our surrounding environment, and it seriously affects our living environment. People's awareness of environmental protection is increasing ... The fire causes water pollution, air pollution and toxic gas pollution to our surrounding environment, and it seriously affects our living environment. People's awareness of environmental protection is increasing year by year, and environmental pollution caused by the fire is also being controlled. This article briefly introduces the fire accident's impact on the environment, the systematic analysis of the fire accident in the source of pollution and its harm. Combined with the existing way of fire fighting and rescue fire accident, the pollution control method is proposed. 展开更多
关键词 fire accident ecological environment pollution control
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基于ColdFire微处理器的消防报警控制器设计 被引量:2
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作者 张云洲 吴成东 +1 位作者 薛定宇 王宏日 《东北大学学报(自然科学版)》 EI CAS CSCD 北大核心 2008年第6期790-793,共4页
为提高分布式消防报警系统的处理能力和反应速度,采用32位ColdFire微处理器MCF5282设计了一款消防报警控制器.阐述了系统结构及硬件接口扩展电路的设计,给出了系统信息流图和软件设计思想.该系统能够完成复杂的联动控制逻辑运算处理,具... 为提高分布式消防报警系统的处理能力和反应速度,采用32位ColdFire微处理器MCF5282设计了一款消防报警控制器.阐述了系统结构及硬件接口扩展电路的设计,给出了系统信息流图和软件设计思想.该系统能够完成复杂的联动控制逻辑运算处理,具有很强的智能性和良好的实时反应能力.实际应用表明,高性能微处理器的引入使消防报警控制器的性能得到了较大的提高. 展开更多
关键词 ColdFire微处理器 消防报警 控制器 硬件扩展 信息处理
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General design principle of artillery for firing accuracy 被引量:3
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作者 Linfang Qian Guangsong Chen +1 位作者 Minghao Tong Jinsong Tang 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2022年第12期2125-2140,共16页
In this paper,based on the topological description method,the kinematic and dynamic equations of the projectile flight and projectile-artillery coupling system during the whole process of firing are constructed.The fa... In this paper,based on the topological description method,the kinematic and dynamic equations of the projectile flight and projectile-artillery coupling system during the whole process of firing are constructed.The factors that can affect the projectile burst points,namely the state parameters of the projectile on the muzzle and state parameters of the barrel muzzle,as well as the factors that affect the barrel muzzle state parameters,are analyzed.On this basis,the design principle of artillery firing accuracy is proposed.The error analysis and the corresponding inverse problem,the extraction method of key parameters affecting artillery implicated motion,the conformal and control method of rotating band are analyzed and presented.Finally,the presented method is verified through a vehicle mounted howitzer case,and the muzzle state parameter interval is obtained meeting the given firing accuracy.In addition,the sensitivity analysis of artillery parameters shows that the less the correlation between the parameters and the barrel,the less the influence on the projectile implicated motion.The analysis of the coupling effect between rifling and the rotating band shows that the uniform rifling is the optimal form for the conformal of the rotating band during firing. 展开更多
关键词 firing accuracy Projectile-artillery coupling Rotating band conformal Sensitivity analysis Error control
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Improving control effects of absence seizures using single-pulse alternately resetting stimulation (SARS) of corticothalamic circuit 被引量:5
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作者 Denggui FAN Yanhong ZHENG +1 位作者 Zecheng YANG Qingyun WANG 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2020年第9期1287-1302,共16页
Presently,we develop a simplified corticothalamic(SCT)model and propose a single-pulse alternately resetting stimulation(SARS)with sequentially applying anodic(A,“+”)or cathodic(C,“−”)phase pulses to the thalamic ... Presently,we develop a simplified corticothalamic(SCT)model and propose a single-pulse alternately resetting stimulation(SARS)with sequentially applying anodic(A,“+”)or cathodic(C,“−”)phase pulses to the thalamic reticular(RE)nuclei,thalamus-cortex(TC)relay nuclei,and cortical excitatory(EX)neurons,respectively.Abatement effects of ACC-SARS of RE,TC,and EX for the 2 Hz-4 Hz spike and wave discharges(SWD)of absence seizures are then concerned.The m∶n on-off ACC-SARS protocol is shown to effectively reduce the SWD with the least current consumption.In particular,when its frequency is out of the 2 Hz-4 Hz SWD dominant rhythm,the desired seizure abatements can be obtained,which can be further improved by our proposed directional steering(DS)stimulation.The dynamical explanations for the SARS induced seizure abatements are lastly given by calculating the averaged mean firing rate(AMFR)of neurons and triggering averaged mean firing rates(TAMFRs)of 2 Hz-4 Hz SWD. 展开更多
关键词 epileptic absence seizure spike and wave discharge(SWD) single-pulse alternately resetting stimulation(SARS) mean field model averaged mean firing rate(AMFR) seizure control
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Fire blight disease, a fast-approaching threat to apple and pear production in China 被引量:29
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作者 ZHAO Yu-qiang TIAN Yan-li +4 位作者 WANG Li-min GENG Guo-min ZHAO Wen-jun HU Bai-shi ZHAO You-fu 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2019年第4期815-820,共6页
Fire blight, caused by Erwinia amylovora, is a devastating disease of apples and pears, causing enormous economic losses around the world. The disease is indigenous to North America and has spread to more than 50 coun... Fire blight, caused by Erwinia amylovora, is a devastating disease of apples and pears, causing enormous economic losses around the world. The disease is indigenous to North America and has spread to more than 50 countries since its discovery in 1870 s. Recent reports of the disease in China's neighboring countries, including South Korea, Kyrgyzstan, and Kazakhstan, pose great threat to the world's leading producer of apples and pears. This mini-review intends to provide an update on the disease, pathogen biology, epidemiology, and control. It will also provide some perspectives and suggestions for the apple and pear industry and growers in China, which will face the imminent threat of this devastating disease. 展开更多
关键词 fire blight ERWINIA amylovora BIOLOGY epidemiology DISEASE control
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Mercury Emission From Coal-fired Power Plants in China 被引量:29
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作者 YIN Libao ZHUO Yuqun +3 位作者 XU Qisheng ZHU Zhenwu DU Wen AN Zhongyi 《中国电机工程学报》 EI CSCD 北大核心 2013年第29期I0001-I0014,共14页
燃煤是最大的人为汞排放源之一,燃煤电厂的汞排放控制问题也越来越为人们所关注。该文将目前公布的中国电厂的汞排放数据进行筛选汇总,得到18个电厂的汞排放数据,通过对比和分析,总结出了符合我国燃煤电厂特点的一般性汞排放规律。... 燃煤是最大的人为汞排放源之一,燃煤电厂的汞排放控制问题也越来越为人们所关注。该文将目前公布的中国电厂的汞排放数据进行筛选汇总,得到18个电厂的汞排放数据,通过对比和分析,总结出了符合我国燃煤电厂特点的一般性汞排放规律。结果表明:与美国煤种相比,我国的燃煤具有低氯、高灰的特性,这不利于汞的排放控制;循环流化床燃烧可能会因燃尽率的不同而较煤粉炉燃烧易获得较高的Hgp;空气污染控制设备的使用能够有效地减少汞排放,选择性催化还原+静电除尘器/布袋除尘器+石灰石-石膏湿法脱硫(SCR+ESP/FF+WFGD)组合的平均脱汞率可达71.48%;SCR的大规模应用可能会将汞大量转移到飞灰和脱硫石膏中,带来二次污染的问题。 展开更多
关键词 燃煤电厂 汞排放 中国 燃煤发电 微量元素 神经系统 排放源 污染物
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Influence of key factors on deflection of bonded prestressed concrete simply supported slabs subjected to fire 被引量:3
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作者 郑文忠 欧阳志为 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2010年第5期615-621,共7页
In order to validate the accuracy of nonlinear fire simulation programs,comparison analysis is carried out between simulation and experiment induced from small-scale specimens,and then fire resistance of large-scale p... In order to validate the accuracy of nonlinear fire simulation programs,comparison analysis is carried out between simulation and experiment induced from small-scale specimens,and then fire resistance of large-scale prestressed concrete slabs is further investigated through parameter expansion.The influences on fire resistance ratings controlled by deflection are explored and discussed,including effective span,concrete cover thickness,load level,prestress degree,effective prestress,composite reinforcement index and other factors.The calculated results indicate that fire resistance ratings of large-scale bonded prestressed concrete simply supported slabs are bigger than those of small-scale ones.Finally,the calculation formulas of fire resistance ratings controlled by deflection are established,which rationally consider the influence of effective span,concrete cover thickness,load level,composite reinforcement index and so on key factors. 展开更多
关键词 bonded prestressed concrete simply supported slabs fire resistance ratings controlled by deflection
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Toxicity and Efficacy of Two Emulsifiable Concentrates of 2-Tridecanone against Red Imported Fire Ants 被引量:2
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作者 Jian Chen 《Advances in Entomology》 2016年第1期37-46,共10页
2-tridecanone is a major constitute of defensive secretion in tawny crazy ants, Nylanderia fulva that is an ant species reported to be able to displace red imported fire ants, Solenopsis invicta in the field. 2-tridec... 2-tridecanone is a major constitute of defensive secretion in tawny crazy ants, Nylanderia fulva that is an ant species reported to be able to displace red imported fire ants, Solenopsis invicta in the field. 2-tridecanone was proven to be toxic to S. invicta. Although 2-tridecanone is commercially available, utilization of this naturally occurring compound in fire ant management has received little attention. In this study, toxicity and efficacy of two 2-tridecanone formulations were assessed against S. invicta. Two emulsifiable concentrates were prepared using 2-tridecanone as an active ingredient, vegetable oil as a solvent and polyoxyethylene tridecyl ether as a surfactant. Piperonyl butoxide (PBO) was used as a synergist in one formulation. Both formulations showed significant toxicity in laboratory bioassays. In a field trial, at application rate of 5.28 mL/L and 14 days after mound drench treatment, 100% control was achieved for formulation with PBO and 90% control for the formulation without PBO. In conclusion, both formulations had significant efficacy against S. invicta. Due to the low mammalian toxicity of 2-tridecanone, no involvement of hazardous synthetic organic solvents, no phytotoxicity at applied concentrations, and relatively low cost, both formulations are promising alternatives to commercial insecticide products for fire ant mound drench. The outstanding efficacy of both formulations observed in this study warrants further research on their efficacy against other pest insects. 展开更多
关键词 Defensive Chemical Fire Ant control Mound Drench
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Distance Control and Positive Security for Intrinsic Equipment Working in Explosive Potential Atmospheres 被引量:2
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作者 Emil Pop Gabriel-Ioan Ilcea Ionut-Alin Popa 《Engineering(科研)》 2018年第3期75-84,共10页
In this paper, intrinsic safety and positive security distance control for an up/down elevator which extracts the materials from an underground coal mine is approached. For a better understanding of intrinsic safety a... In this paper, intrinsic safety and positive security distance control for an up/down elevator which extracts the materials from an underground coal mine is approached. For a better understanding of intrinsic safety and positive security, the first part of the paper describes the potential risk the workers are facing while working in dangerous environments like coal mining with “grisou” atmospheres and what the conditions of an unfortunate event to take place are. We presented the diagram and working principle for intrinsic safety equipment used in potential explosive areas based on which we modeled and simulated the intrinsic and positive security distance control in order to get a software solution for it. We created an algorithm and simulated the process in Matlab Simulink. The simulation results done in Matlab Simulink were then entered into a Moeller PLC using a ladder-type programming language. For protection against explosive atmospheres, the PLC is inserted into a metal housing with intrinsic protection and Positive Security. 展开更多
关键词 Fire TRIANGLE DISTANCE control POSITIVE SECURITY Explosion Risk INTRINSIC Safety
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STUDY ON THE EFFECT OF CLIMATE CHANGE ON FOREST FIRE IN HEILONGJIANG PROVINCE
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作者 姜乃准 段文标 朱峰 《Journal of Northeast Forestry University》 SCIE CAS CSCD 1996年第1期26-28,共3页
According to the data of historical climate passed 100 years, the comprehensive effect of various factors, including seawater temperature,sunspots activities, volcanic explosion, co2 concentration,o3 con centration an... According to the data of historical climate passed 100 years, the comprehensive effect of various factors, including seawater temperature,sunspots activities, volcanic explosion, co2 concentration,o3 con centration and atmospheric circulation index,climate change of Heilong jiang province,was analyzed.The tendency of climate change of Heilong jiang province in the next ten years was predicted. The influence of climate change on forest fire was put forward and response strategy was briefly discussed. 展开更多
关键词 CLIMATE CHANGE FOREST FIRE FOREST FIRE control
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APPLICATION OF DIRECT BTT GUIDANCE LAW BASED ON NONLINEAR INVERSE SYSTEM THEORY TO INTEGRATED FIRE/FLIGHT SYSTEMS(IFFS)
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作者 Ma Xiaojun Zhang Minglian Wen Chuanyuan(Faculty 305, Beijing University Of Aeronautics and Astronautics,Beijing, China, 100083) 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 1996年第4期305-311,共7页
To counter BTT guidance mode, new relative motion equations of the targetaircraft and the attack aircraft are proposed. The inverse system theory of the nonlinearcontrol is used, and the direct BTT-180 guidance comman... To counter BTT guidance mode, new relative motion equations of the targetaircraft and the attack aircraft are proposed. The inverse system theory of the nonlinearcontrol is used, and the direct BTT-180 guidance command is solved, which can operatethe attack aircraft to automatically complete the flight mission of the preceding stage ofthe terminal weapon delivery, and thus the automatic attack is extended from the stage ofthe terminal weapon delivery to the preceding stage of the terminal weapon delivery. 展开更多
关键词 fire control flight control nonlinear systems inverse system direct BTT guidance law automatic control ATTACK
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Mathematical Modeling of Crown Forest Fire Spread
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作者 Valeriy Perminov 《Open Journal of Forestry》 2012年第1期17-22,共6页
Mathematical model of forest fire was based on an analysis of known experimental data and using concept and methods from reactive media mechanics. In this paper the assignment and theoretical investigations of the pro... Mathematical model of forest fire was based on an analysis of known experimental data and using concept and methods from reactive media mechanics. In this paper the assignment and theoretical investigations of the problems of crown forest fire spread in windy condition were carried out. In this context, a study—mathematical modeling—of the conditions of forest fire spreading that would make it possible to obtain a detailed picture of the change in the temperature and component concentration fields with time, and determine as well as the limiting condition of fire propagation in forest with fire break. 展开更多
关键词 FOREST FIRE MATHEMATICAL Model Turbulence Ignition FIRE SPREAD control Volume Discrete ANALOGUE
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The Effects of SO_3 in Flue Gas on the Operation of Coalfired Units and Countermeasures
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作者 Hu Yufeng Xue Jianming 《Meteorological and Environmental Research》 CAS 2017年第5期120-124,共5页
There exists a certain amount of SO_3 in flue gas discharged from coal-fired power plants. With the operation of the selective catalystic reduction( SCR) denitrification system,SO_3 concentration in the flue gas incre... There exists a certain amount of SO_3 in flue gas discharged from coal-fired power plants. With the operation of the selective catalystic reduction( SCR) denitrification system,SO_3 concentration in the flue gas increases,which will lead to fouling,erosion and plugging of downstream equipment. In this study,the main effects of SO_3 on the safety,stability and efficiency of units were analyzed,and measures to control SO_3 were proposed. 展开更多
关键词 Coal-fired flue gas SO3 Operation of units control of SO3
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