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AERODYNAMIC CHARACTERISTICS ABOUT MINING DUMP TRUCK AND THE IMPROVEMENT OF HEAD SHAPE

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Journal of Hydrodynamics 2008年第6期20卷 713-718页

作者： WEI Xiu-ling WANG Guo-qiang FENG Su-li College of Mechanical Science and engineering Jilin University Changchun 130022 China department of Aeronautic Mechanical engineering Aviation University of Air force Changchun 130022 China Fundamental Science department Armor Technique Institute Changchun 130117 China

The external flow field around a certain mining dump truck was simulated. The airflow structure and the aerodynamic drag were discussed, and the relationship between airflow characteristics and aerodynamic drag were obtained. In order to solve the problem of head shape of the truck, three scenarios including edge rounding, installing splitter planes and their combination were put forward to improve the head shape through numerical simulation and analysis. The model and method were selected to be three dimensional and time-independent. The Reynolds-averaged Navier-Stokes equations were solved using the finite volume method. The RNG k-ε model was chosen for the closure of the turbulent quantities. The results show that the third scenario is the best one, because of its aerodynamic characteristics being better than those of unimproved model.

关键词： dump truck external flow field numerical simulation

Selection of Weather Parameters for air-Conditioning System Design for Buildings with Long Thermal Lag

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湖南大学学报（自然科学版） 2009年第S1期36卷 79-82页

作者： GE Lian-feng1,2,LEI Ming3,CHEN You-ming1,2(1.College of Civil engineering,Hunan university,Changsha,Hunan 410082,china 2.Key Laboratory of Building Safety and Energy Efficiency,MOE,china (3.aviation Theory department,aviation university of air force,changchun,Jilin 130022,china) College of Civil engineering Hunan University Changsha 410082 China Key Laboratory of Building Safety and Energy Efficiency China aviation Theory department Aviation University of Air Force Changchun 130022 China

Two building factors-a longer thermal lag of more than one hour for building envelops and a lag of indoor radiation to convert into cooling load-have impact on the instantaneous heat input and instantaneous cooling *** the two factors should be taken into account when selecting the weather parameters for air-conditioning system *** paper developed a new statistic method for the rational selection of coincident solar irradiance,dry-bulb and wet-bulb *** method was applied to historic weather records of 25 years in Hong Kong to generate coincident design weather *** the results show that traditional design solar irradiance,dry-bulb and wet-bulb temperatures may be significantly overestimated in many conditions,and the design weather data for the three different constructions is not kept constant.

关键词： building construction thermal lag system capacity design weather data air-conditioning

The Research on Regenerative Furnace Combustion Control Based on Multi-scale Wavelet Network

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The Research on Regenerative Furnace Combustion Control Base...

2009中国控制与决策会议

作者： Yang Xiao Hong~1,You Wen~2,Zhang Yan~3 1.department of aviation Control engineering,aviation university of air force,changchun 130021 2.department of Electric engineering and Electronic Science,Chang Chun university of Technology 130012 3.department of Computer Science,aviation university of air force,changchun 130022,china

＜正＞This article proposes a compound control *** is based on the multi-resolution wavelet controller,the sub-controller and the PID-NNC master-controller and integrated with the WNN wavelet neural network *** strategy can be used to overcome effectively bad influences caused by the system initiation,the control mode,the object change and the exterior disturbance to the regenerative furnace in the process of combustion temperature *** strategy has such characteristics as quick response,small overshoot,high stable state precision,strong robustness and etc. It can not be realized easily by conventional PID control,which has been proved by the simulation *** offers a new way for applying the wavelet transformation in the steel metallurgy controlling domain and a new direction for saving energy and reducing consumption.

关键词： Regenerative Furnace Multi-scale Wavelet Network Dual-crossing Temperature Control

Compact Broad Dual-Band Antenna Using A Shorted Patch with A Thick air Substrate for Wireless Body Area Network Application

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Compact Broad Dual-Band Antenna Using A Shorted Patch with A...

2011 4th IEEE International Symposium on Microwave,Antenna,Propagation and EMC Technologies for Wireless Communications

作者： Guangdong Liu Degong Wang Fulu Jin Shuo Chang aviation Electronic engineering department aviation university of air force changchun china

In this paper,a compact broadband antenna operated at 2.45 GHz and 5.8 GHz with the patch size of 22×16mm is *** both simulated and tested results,the desired broadside pattern,and also the bandwidth of 100MHz （4%） for 2.45 GHz and of 200MHz （3.5%） for 5.8 GHz are *** bandwidths are large enough to meet the requirements of wireless body area network,*** antenna gain is measured as about 0.5 dBi and 1.5 dBi for the lower and higher resonant frequency,*** resonant frequency are both slightly shift down when the antenna is placed near human body.

关键词： antenna wireless body area network WLAN

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基于混合式控制结构的多机器人编队控制研究

计算机工程与应用 2010年第11期46卷 49-52页

作者：雷艳敏朱齐丹冯志彬哈尔滨工程大学自动化学院哈尔滨150001 长春大学电子信息工程学院长春130022 空军航空大学航空救生系长春130021

针对多机器人的编队控制问题,提出把基于Motor Schema的反应式控制结构和分层式结构结合起来,设计了一种混合式体系结构。根据反应式结构设计了四种基本行为,并提出利用模糊神经网络来设计各种行为。最后利用神经元来融合各种行为的输... 详细信息

针对多机器人的编队控制问题,提出把基于Motor Schema的反应式控制结构和分层式结构结合起来,设计了一种混合式体系结构。根据反应式结构设计了四种基本行为,并提出利用模糊神经网络来设计各种行为。最后利用神经元来融合各种行为的输出作为最终的输出,控制执行器来执行动作。该方法提高了整个编队系统的智能性和环境适应性。通过仿真验证了该方法的可行性和有效性。

关键词：编队控制体系结构模糊神经网络神经元

The Endpoint Forecast of AOD Stove Ferroalloy Steel-Making Based on Wavelet Neural Network

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The Endpoint Forecast of AOD Stove Ferroalloy Steel-Making B...

2010 Chinese Control and Decision Conference

作者： Yangxiao Hong~1,Xu Jing~2,Yanghong Tao~3 1.department of aviation Control engineering,aviation university of air force,changchun,130021 2.department of Neurology Internal Medicine,First Hospital of Jilin university,changchun,130012 3.department of Electric engineering and Electronic Science,Chang Chun university of Technology 130012,china

＜正＞The AOD stove ferroalloy steel-making endpoint temperature and the ingredient are the control objectives of AOD stove ferroalloy steel-making,which has serious nonlinear relations with variables such as oxygen blown quantity and the quantity of molten steel and is unable to measure continuously *** article develops a set of AOD stove smelt ferroalloy end-point control model based on the wavelet neural network and some actual data of a 180t AOD ferroalloy stove in Jilin Ferroalloy Factory to conduct the model verification *** forecasting the end-point temperature and the carbon content and gathering the spot operating data and the practical application,we can see that the double hit probability of carbon and temperature reaches above 80%.

关键词： AOD Stove Ferroalloy Forecast Wavelet Neural Network

The Research on the Automatic Measurement of Frequency Characteristics of Opto-electronic Platform

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The Research on the Automatic Measurement of Frequency Chara...

2010 International Conference on Computer,Mechatronics, Control and Electronic engineering (CMCE 2010)

作者： Hui Liu1,2,Siyuan Gao1,Bo Liu1,Juan Chen1,Hongguang Jia1 1.changchun Institute of Optics,Fine Mechanics and Physics,Chinese Academy of Sciences changchun,Jilin Province,china 2.Graduate university of Chinese Academy of Science Beijing,china Wei Liang aviation ordnance engineering department,aviation university of air force changchun,Jilin Province,china

A new frequency characteristic test method is proposed based on the digitization characteristics of opto-electronic platform servo *** a digital processing controller is used to automatically test the entire process and tested data are uploaded to a PC through CAN-bus,and then the tested data are transferred into accurate transfer function with the Levy *** we discuss the testing steps,the data processing,the extraction,the Bode diagram plotting and the model identification in *** corresponding experiments are carried out,and the results show that the method is simple with the features of high efficiency,high precision and engineering feasibility.

关键词： Index Terms-opto-electronic platform Levy identification frequency characteristics measurement correlation analysis

Study on active vibration control technique based on cantilever beam

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Study on active vibration control technique based on cantile...

2010 International Conference on Computer,Mechatronics, Control and Electronic engineering (CMCE 2010)

作者： Dong Jingshi1, Guo Kang1, Zheng Wei1, Shen Chuanliang1,Cheng Guangming1 1.College of Mechanical Science and engineering 2.College of Automotive engineering Jilin university changchun,china Ding Ji department of Mechanical engineering aviation university of air force changchun,china

In order to solve the contradiction between lightweight and noise of a vibrating cantilever beam, active control actuated by piezoelectric ceramics is presented in this study. The dynamic model of the cantilever beam is established by finite element method (FEM). The piezoelectric actuator excited by control signal is bonded near the fixed end of the cantilever beam to suppress the beam's first vibration mode. The control signal is collected by a sensor and processed by the quadratic optimal control theory. Experiment results show that the amplitude of the active controlled cantilever beam is reduced to 48.2% than the uncontrolled one under constant external excitation.

关键词： active control cantilever beam piezoelectric actuator finite element method LabVIEW

基于Opt-rec多小波数字水印嵌入新方法

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计算机工程与应用 2004年第36期40卷 33-34,72页

作者：杨建波陈贺新王选贺吉林大学通信工程学院

以图像作水印且提取时不需要原图像的数字水印技术面临许多挑战,因而,有关这种技术的研究文献很少。该文首次提出了一种基于遗传算法和Opt-rec多小波、利用奇偶性嵌入灰度图像的公开水印新技术。Opt-rec多小波具有对称性、正交性、在眼... 详细信息

以图像作水印且提取时不需要原图像的数字水印技术面临许多挑战,因而,有关这种技术的研究文献很少。该文首次提出了一种基于遗传算法和Opt-rec多小波、利用奇偶性嵌入灰度图像的公开水印新技术。Opt-rec多小波具有对称性、正交性、在眼0,1演有限支撑、无边界失真,对前置滤波器选取具有任意性,因而Opt-rec多小波比普通小波具有更为广泛的应用前景。选择适应度函数,在适当的约束条件下,通过遗传算法,对不同的图像自适应地得到Opt-rec多小波变换的前置滤波器和后置前置滤波器;将灰度水印图像分解成位图,宿主图像进行一层多小波分解,每个低频系数嵌入1比特水印信息;若嵌入“1”,使对应的低频系数四舍五入为奇数,嵌入“0”,则使其为偶数,相反亦可。该算法提取的水印无失真,可以改善水印系统不可感知性和不可统计性。实验结果表明,该方法抗剪切攻击能力较强,但其抵抗噪声、压缩等处理的能力较差。

关键词：数字水印 Opt-rec多小波遗传算法相关度鲁棒性透明性