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PLE spectra analysis of the sub-structure in the absorption spectra of CdSeS quantum dots 被引量:2
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作者 刘炳灿 潘学琴 +1 位作者 田强 吴正龙 《Chinese Physics B》 SCIE EI CAS CSCD 2006年第5期1067-1070,共4页
The semiconductor CdSeS quantum dots (QDs) embedded in glass are analysed by means of absorption spectra, photoluminescence (PL) spectra and photoluminescence excitation (PLE) spectra. The peaks of absorption sp... The semiconductor CdSeS quantum dots (QDs) embedded in glass are analysed by means of absorption spectra, photoluminescence (PL) spectra and photoluminescence excitation (PLE) spectra. The peaks of absorption spectra shift to lower energies with the size of QD increasing, which obviously shows a quantum-size effect. Using the PLE spectra, the physical origin of the lowest absorption peak is analysed. In PLE spectra, the lowest absorption peak can be deconvoluted into two peaks that stem from the transitions of 1S3/2-1Se and 2S3/2-1Se respectively. The measured energy difference between the two peaks is found to decrease with the size of QD increasing, which agrees well with the theoretical calculation for the two transitions. The luminescence peak of defect states is also analysed by PLE spectra. Two transitions are present in the PLE, which indicates that the transitions of 1S3/2 1Se and 2S3/2 1Se are responsible for the defect states luminescence. 展开更多
关键词 CdSeS PL spectra PLE spectra defect state
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Analysis on Thermal Current Field in Powertrain Cabin of Tracked Vehicles With Electric Transmission System Configuration-2 被引量:1
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作者 张豫南 李瀚飞 +4 位作者 颜南明 尚颖辉 王冬 李源 袁文涛 《Defence Technology(防务技术)》 SCIE EI CAS 2007年第1期1-6,共6页
The electric transmission system congfiguration-2 is one of the main electric drives for tracked vehicles. The geometrical model for the power-train cabin is established and the preliminary design for its cooling syst... The electric transmission system congfiguration-2 is one of the main electric drives for tracked vehicles. The geometrical model for the power-train cabin is established and the preliminary design for its cooling system is implemented. The mathematic model is established for thermal current field computation, simulation and analysis in the powertrain cabin. The three-dimensional structure of the powertrain cabin is optimized. The validity of the cooling system design is proved. The foundation for optimizing the whole electric transmission system configuration is laid. 展开更多
关键词 履带车辆 电传动系统 电传系舱室 热流场 结构优化 数学模型
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Statistical Analysis of Human Reliability of Armored Equipment 被引量:1
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作者 刘维平 曹伟国 任晶 《Defence Technology(防务技术)》 SCIE EI CAS 2007年第3期230-234,共5页
Human errors of seven types of armored equipment, which occur during the course of field test, are statistically analyzed. The human error-to-armored equipment failure ratio is obtained. The causes of human errors are... Human errors of seven types of armored equipment, which occur during the course of field test, are statistically analyzed. The human error-to-armored equipment failure ratio is obtained. The causes of human errors are analyzed. The distribution law of human errors is acquired. The ratio of human errors and human reliability index are also calculated. 展开更多
关键词 数理统计学 装甲装备 操作错误事故 统计量
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Adjusting the Parameters of PI Regulator in All-electrical Tank Gun Control System by Computer Program
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作者 臧克茂 贺跃 +1 位作者 李匡成 李长兵 《Defence Technology(防务技术)》 SCIE EI CAS 2005年第2期140-145,共6页
Both the traverse subsystem and the elevation subsystem of the all-electrical tank gun control system are composed of electrical drive control system respectively. The parameters of PI regulator in these electrical dr... Both the traverse subsystem and the elevation subsystem of the all-electrical tank gun control system are composed of electrical drive control system respectively. The parameters of PI regulator in these electrical drive control systems affect the performance of the control system seriously. Up to now, there is not a simple and practical method for choosing regulator parameters, which are usually determined by repeated and continual readjustment. This method is low efficient, and the parameters got are not always optimal. A method for on-line adjusting the parameters of PI regulator in the electrical drive control system by computer program is introduced in this paper. The function of adjusting PI parameters of the electrical drive control system is realized by PC program written by VC++ and controlling program written by assemble language and by the communication between PC and DSP completed by the control MSCOMM in VC++6.0. The method as mentioned above which is applied for an all-electrical tank gun control system under development is proved very available, a better performance might be obtained for the all-electrical tank gun control system easily. 展开更多
关键词 PI REGULATOR SERIAL communication all-electrical TANK GUN control system
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Vibration Severity Monitoring and Evaluation of Armored Vehicle Transmission
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作者 樊新海 王传菲 +1 位作者 安钢 王战军 《Defence Technology(防务技术)》 SCIE EI CAS 2009年第4期256-260,共5页
Vibration monitoring and vibration severity evaluation of armored vehicle transmission are realized by additional sensors. An algorithm of vibration severity in frequency domain is presented. The algorithm has powerfu... Vibration monitoring and vibration severity evaluation of armored vehicle transmission are realized by additional sensors. An algorithm of vibration severity in frequency domain is presented. The algorithm has powerful applicability for signal type and flexible selectivity for frequency range,and avoids the processing of signal conversion used calculus and filtering compared to the algorithm of vibration severity in time domain. An applied example is given in company with attentive proceedings and measures for improving evaluation effect. 展开更多
关键词 MECHANICS armored vehicle TRANSMISSION condition monitoring vibration standard vibration severity
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Numerical Simulation of Airflow Field and Structure Improvement in Engine Compartment of Armored Vehicles with Electric Transmission
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作者 王宪成 索文超 牛庆银 《Defence Technology(防务技术)》 SCIE EI CAS 2008年第1期7-12,共6页
When the mechanical drive is changed into the electric transmission,the cooling system of the engine compartment should be altered to meet the new requirement for the increasing in equipment such as electric apparatus... When the mechanical drive is changed into the electric transmission,the cooling system of the engine compartment should be altered to meet the new requirement for the increasing in equipment such as electric apparatus.In order to predict and analyze the rationality of cooling system in the virtual engine compartment,the numerical simulation of airflow fields in the engine compartment by using computational fluid dynamics(CFD) technique is necessary.An armored vehicle with electric transmission in the research is taken as the research object.The physical model and mathematical model for the computation of 3D air flow and heat transfer in the engine compartment of an armored vehicle with electric transmission is established.Turbulent flow in the compartment is described by using the standard k-ε two-equation turbulence model.The temperature and velocity fields of 3D air flow in the engine compartment are numerically simulated and analyzed based on different fan's flux.A theoretical basis for determination of the fan's flux is given by the simulation results.The positions of the air-vent shutter are analyzed.The simulation results show that the different positions of the air-vent shutter can lead to different cooling efficiencies. 展开更多
关键词 流体力学 装甲车 机舱 数字模拟
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Sliding wear behavior of high velocity arc sprayed Fe-Al coating 被引量:5
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作者 朱子新 徐滨士 +1 位作者 马世宁 张伟 《China Welding》 EI CAS 2003年第1期1-5,共5页
The friction and wear behavior of Fe Al intermetallics based coating produced by high velocity arc spraying technique under dry sliding at room temperature were investigated using a ball on disc tribotester. The ef... The friction and wear behavior of Fe Al intermetallics based coating produced by high velocity arc spraying technique under dry sliding at room temperature were investigated using a ball on disc tribotester. The effect of sliding speed on friction coefficient and wear of the coating was studied. The worn surface of the coating was analyzed by scanning electron microscope (SEM) to explore sliding friction and wear mechanism. The results show that the variations of friction coefficient can be divided into three distinct steps during the trail. Both the friction coefficient and the wear of the coating increase with increased sliding speed due to accelerated crack propagation rate and lamellar structure with poor ductility of the coating. The coating surface is subjected to alternately tensile stress and compression stress during sliding wear process, and the predominant wear mechanism of the coatings appears to be brittle fracture and delamination. 展开更多
关键词 Fe Al intermetallics COATING friction and wear behavior high velocity arc spraying
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Analysis on Dynamic Response of Hard-Soft-Hard Sandwich Panel Under Blast Loading 被引量:2
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作者 DONG Yongxiang FENG Shunshan JIN Jun 《Transactions of Tianjin University》 EI CAS 2006年第B09期233-237,共5页
Surface contact explosion experiments have been performed for the study of dynamic response of the hard-soft-hard sandwich panel under blast loading. Experimental results have shown that there are four damage modes, i... Surface contact explosion experiments have been performed for the study of dynamic response of the hard-soft-hard sandwich panel under blast loading. Experimental results have shown that there are four damage modes, including explosion cratering, scabbing of the backside, radial cracking induced failure and circumferential cracking induced failure. It also illustrates that the foam material sandwiched in the multi-layered media has an important effect on damage patterns. The phenomena encountered have been analyzed by the calculation with ALE method. Meanwhile, the optimal analysis of foam material thickness and position in the sandwich panel were performed in terms of experimental and numerical analysis. The proper thickness proportion of the soft layer is about 2.0% to the thickness of sandwich panel and the thickness of the upper hard layer and lower hard layer is in the ratio of ? to 3 under the condition in this paper when the total thickness of soft layer remains constant. 展开更多
关键词 dynamic response sandwich panel blast loading foam material
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Path planning for MIG surfacing of robot-based remanufacturing system 被引量:2
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作者 朱胜 梁嫒嫒 《China Welding》 EI CAS 2006年第4期59-62,共4页
Robot-based remanufacturing system can scan the worn parts and develop the corresponding models, compare them with the standard model, calculate the weld deposit, implement welding path planning, and repair the worn p... Robot-based remanufacturing system can scan the worn parts and develop the corresponding models, compare them with the standard model, calculate the weld deposit, implement welding path planning, and repair the worn parts with MIG surfacing automatically. This paper investigates the welding path planning after calibrating, scanning and model rebuilding. The following aspects are contained: introducing the planning principle, selecting the suitable welding process based on welding parameters (current and speed), calculating welding overlap quantity by the superposition method. Also, it has been verified that good weld profile can be obtained with the optimized parameters. 展开更多
关键词 robot-based remanufacturing system path planning welding parameters welding overlap
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Study on Effects of Oxydal on Diesel Engine Combustion
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作者 王宪成 孙志新 +1 位作者 王益军 马向平 《Defence Technology(防务技术)》 SCIE EI CAS 2010年第2期81-84,共4页
Based on the analysis of the high temperature decomposition of oxydal(H2O2)and the combustion of diesel engine,the effects of H2O2 on the improvement of diesel combustion were studied.An oxydal spray system was design... Based on the analysis of the high temperature decomposition of oxydal(H2O2)and the combustion of diesel engine,the effects of H2O2 on the improvement of diesel combustion were studied.An oxydal spray system was designed to inject H2O2/water mixture into the manifold.The experiment was carried out on a 1135 diesel engine bench.The results show that H2O2 injection can make the curve of heat release rate move forward and decrease its peak value.The specific fuel consumption is decreased a little,while both NOx and PM emission are obviously reduced. 展开更多
关键词 power machinery engineering diesel engine H2O2 COMBUSTION EMISSION
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Analysis and Comparison of Electric Drive System Projects of Military Tracked Vehicles
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作者 廖自力 马晓军 +1 位作者 赵玉慧 臧克茂 《Defence Technology(防务技术)》 SCIE EI CAS 2007年第2期81-85,共5页
The electric drive system characteristics of different projects for tracked vehicles are analyzed.For the two most typical projects,the parameters of power,torque and rotating speed and others of drive motor are figur... The electric drive system characteristics of different projects for tracked vehicles are analyzed.For the two most typical projects,the parameters of power,torque and rotating speed and others of drive motor are figured out under the condition of satisfying adequate steering performance of the tracked vehicles.General opinions on the two projects are brought forward and conclusions are drawn. 展开更多
关键词 机械工程 轨道 装甲车 汽车工程
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Investigation on in-flight particle velocity in supersonic plasma spraying 被引量:3
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作者 李长青 马世宁 叶雄林 《China Welding》 EI CAS 2005年第1期80-84,共5页
In-flight particle velocity and flux distribution were measured using CCD thermal spray monitor system during supersonic plasma spray processing with nano-structured Al_2O_3-TiO_2 feed stocks. According to the results... In-flight particle velocity and flux distribution were measured using CCD thermal spray monitor system during supersonic plasma spray processing with nano-structured Al_2O_3-TiO_2 feed stocks. According to the results of particle flux measurement, the largest radian of the divergent particle stream is about 0.2. Within the measuring range, top speed of in-flight particles reached 800m/s. Particle acceleration was accomplished within 4cm down stream of the nozzle. Average particle velocity (about 450m/s) exceeded local sound speed (340m/s) even at a mean standoff distance of 17cm. With increasing mean standoff distance, average velocity of in-flight particle decreased according to a parabolic rule approximately. Image diagnosis showed that the result of in-flight particle velocity measurement is credible. 展开更多
关键词 SUPERSONIC plasma spraying in-flight particle VELOCITY CCD image process
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Progress of remanufacturing engineering and future technology expectation 被引量:3
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作者 Bin-Shi Xu 《Advances in Manufacturing》 SCIE CAS 2013年第1期8-12,共5页
After development for decades, abroad remanufacturing has formed a complete industrial system. At present, the research emphases are on marking logistics management and market cultivation theory of remanufacturing pro... After development for decades, abroad remanufacturing has formed a complete industrial system. At present, the research emphases are on marking logistics management and market cultivation theory of remanufacturing products, and so on. The Chinese remanufacturing starts fairly late. After 10 years of development, it formed a remanufacturing mode with Chinese characteristics that is sustained by high-tech industries, using the surface engineering technology to restore the size and improve properties, and combining manufacturing, study and research together. The remanufacturing mode is not only circular but also economic. With the development of science and technology, future remanufacturing technology will break the previous limits, explore and understand the limits of micro machining. It will carry out the waste product remanufacturing in the micro-nano scale, and extend the remanufacturing industry to a more broad space. 展开更多
关键词 Sustainable development Remanufacturingindustry - Surface engineering - Micro-nano machining
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Research on Gear-broken Fault Diagnosis in a Tank Gearbox 被引量:1
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作者 安钢 李胜利 +1 位作者 樊新海 赵沛然 《Defence Technology(防务技术)》 SCIE EI CAS 2007年第4期251-255,共5页
A fault diagnosis method of working position gear in a tank gearbox is put forward based on simulating the fault of working position gear in an actual tank,extracting the envelope of vibration signal by Hilbert transf... A fault diagnosis method of working position gear in a tank gearbox is put forward based on simulating the fault of working position gear in an actual tank,extracting the envelope of vibration signal by Hilbert transformation amplitude demodulation method,and zooming the low-frequency band to envelope signal. 展开更多
关键词 坦克 变速箱 齿轮断裂 故障诊断 特征提取
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Five modified boundary scan adaptive test generation algorithms 被引量:1
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作者 Niu Chunping Ren Zheping Yao Zongzhong 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2006年第4期760-763,768,共5页
To study the diagnostic problem of Wire-OR (W-O) interconnect fault of PCB (Printed Circuit Board), five modified boundary scan adaptive algorithms for interconnect test are put forward. These algorithms apply Glo... To study the diagnostic problem of Wire-OR (W-O) interconnect fault of PCB (Printed Circuit Board), five modified boundary scan adaptive algorithms for interconnect test are put forward. These algorithms apply Global-diagnosis sequence algorithm to replace the equal weight algorithm of primary test, and the test time is shortened without changing the fault diagnostic capability. The descriptions of five modified adaptive test algorithms are presented, and the capability comparison between the modified algorithm and the original algorithm is made to prove the validity of these algorithms. 展开更多
关键词 boundary scan adaptive test interconnect test algorithm.
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Upper Bounds of the Rates of Decay for Solutions of the Boussinesq Equations
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作者 Ying Liu 《Acta Mathematicae Applicatae Sinica》 SCIE CSCD 2011年第1期105-114,共10页
In this paper, upper bounds of the L2-decay rate for the Boussinesq equations are considered. Using the L2 decay rate of solutions for the heat equation, and assuming that the solutions of the Boussinesq equations are... In this paper, upper bounds of the L2-decay rate for the Boussinesq equations are considered. Using the L2 decay rate of solutions for the heat equation, and assuming that the solutions of the Boussinesq equations are smooth, we obtain the upper bounds of L2 decay rate for the smooth solutions and difference between the solutions of the Boussinesq equations and those of the heat system with the same initial data. The decay results may then be obtained by passing to the limit of approximating sequences of solutions. The main tool is the Fourier splitting method. 展开更多
关键词 the Boussinesq equations L2 decay Fourier splitting method
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A New Primary Lazy Update Propagation Protocol for Replicated Databases
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作者 YANG Zhao-hong GONG Yun-zhan BI Xue-jun 《Wuhan University Journal of Natural Sciences》 EI CAS 2006年第1期263-268,共6页
This paper proposes a new primary lazy update protocol, PTCS (Primary Transaction Commit Schedule). In the PTCS protocol, a serializable primary transaction schedule is generated firstly and then the secondary trans... This paper proposes a new primary lazy update protocol, PTCS (Primary Transaction Commit Schedule). In the PTCS protocol, a serializable primary transaction schedule is generated firstly and then the secondary transactions are committed according to the serializable primary transaction schedule. PTCS protocol can guarantee serializability if the data copy graph contains no directed circles. It can also be ex tended to eliminate all requirements on the data copy graph. Compared to earlier works, PTCS protocol not only imposes a much weaker requirement on the data placement, but also avoids the deadlock caused by transaction waits and extra message overhead. The performance experiments show that the degradation of the performance caused by the replica man- agement of the PTCS protocol is tolerable. 展开更多
关键词 data replication global serializability data copy graph
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Technology of self-repairing and reinforcement of metal worn surface
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作者 Yi Xu Fei Gao +2 位作者 Bo Zhang Feng Nan Bin-Shi Xu 《Advances in Manufacturing》 SCIE CAS 2013年第1期102-105,共4页
Researches on self-repairing material (serpentine phyllosilicate) of our team in the past few years, such as ultrafining treatment, surface modification, self-repairing mechanism, the effect of rare metal on the sel... Researches on self-repairing material (serpentine phyllosilicate) of our team in the past few years, such as ultrafining treatment, surface modification, self-repairing mechanism, the effect of rare metal on the self-repairing performance of serpentine, were introduced summarily. The phyllosilicate of serpentine shows excellent tribologi- cal and self-repairing performance for metal worn surface as additive in lubricant. 展开更多
关键词 Self-repairing performance - Self-repairingmechanism - Serpentine
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Existence,Orbital Stability and Instability of Solitary Waves for Coupled BBM Equations
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作者 Li-wei Cui 《Acta Mathematicae Applicatae Sinica》 SCIE CSCD 2009年第1期1-10,共10页
This paper is concerned with the orbital stability/instability of solitary waves for coupled BBM equations which have Hamiltonian form. The explicit solitary wave solutions will be worked out first. Then by detailed s... This paper is concerned with the orbital stability/instability of solitary waves for coupled BBM equations which have Hamiltonian form. The explicit solitary wave solutions will be worked out first. Then by detailed spectral analysis and decaying estimates of solutions for the initial value problem, we obtain the orbital stability/instability of solitary waves. 展开更多
关键词 Solitary wave orbital stability/instability spectral analysis decaying estimate
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Robotic GMAW forming remanufacturing technology 被引量:6
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作者 Sheng Zhu 《Advances in Manufacturing》 SCIE CAS 2013年第1期87-90,共4页
Robotic GMAW forming process with the advantages of high productivity and high bond strength has become an important forming remanufacturing technology. In this paper, our recent research achievements are introduced a... Robotic GMAW forming process with the advantages of high productivity and high bond strength has become an important forming remanufacturing technology. In this paper, our recent research achievements are introduced and our development prospect on robotic GMAW forming remanufacturing is declared. 展开更多
关键词 REMANUFACTURING GMAW forming ROBOT
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