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回转窑掺烧高炉煤气的计器系统
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作者 贾飙 《马钢技术》 2001年第C00期28-29,共2页
本文介绍了第三烧 玫回转窑掺烧高炉煤气的计器系统,包括煤气压力与流量的检测、煤气流量孔板的选定、煤气累积量折编制及其使用后的效益。
关键词 高炉煤气 流量累积 流量计量 计器系统 回转窑 掺烧
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Several Classes of Two-weight or Three-weight Linear Codes and Their Applications
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作者 Shen Hongyan Liu Haibo 《数学理论与应用》 2024年第3期25-49,共25页
Recently,linear codes with a few weights have been extensively studied due to their applications in secret sharing schemes,constant composition codes,strongly regular graphs and so on.In this paper,based on the Weil s... Recently,linear codes with a few weights have been extensively studied due to their applications in secret sharing schemes,constant composition codes,strongly regular graphs and so on.In this paper,based on the Weil sums,several classes of two-weight or three-weight linear codes are presented by choosing a proper defining set,and their weight enumerators and complete weight enumerators are determined.Furthermore,these codes are proven to be minimal.By puncturing these linear codes,two classes of two-weight projective codes are obtained,and the parameters of the corresponding strongly regular graph are given.This paper generalizes the results of[7]. 展开更多
关键词 Weil sum Linear code Complete weight enumerator Minimal code Strongly regular graph
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State Estimation Method for GNSS/INS/Visual Multi-sensor Fusion Based on Factor Graph Optimization for Unmanned System
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作者 ZHU Zekun YANG Zhong +2 位作者 XUE Bayang ZHANG Chi YANG Xin 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2024年第S01期43-51,共9页
With the development of unmanned driving technology,intelligent robots and drones,high-precision localization,navigation and state estimation technologies have also made great progress.Traditional global navigation sa... With the development of unmanned driving technology,intelligent robots and drones,high-precision localization,navigation and state estimation technologies have also made great progress.Traditional global navigation satellite system/inertial navigation system(GNSS/INS)integrated navigation systems can provide high-precision navigation information continuously.However,when this system is applied to indoor or GNSS-denied environments,such as outdoor substations with strong electromagnetic interference and complex dense spaces,it is often unable to obtain high-precision GNSS positioning data.The positioning and orientation errors will diverge and accumulate rapidly,which cannot meet the high-precision localization requirements in large-scale and long-distance navigation scenarios.This paper proposes a method of high-precision state estimation with fusion of GNSS/INS/Vision using a nonlinear optimizer factor graph optimization as the basis for multi-source optimization.Through the collected experimental data and simulation results,this system shows good performance in the indoor environment and the environment with partial GNSS signal loss. 展开更多
关键词 state estimation multi-sensor fusion combined navigation factor graph optimization complex environments
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Initial Alignment Technique for SINS of Vehicles in the Moving State 被引量:17
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作者 缪玲娟 沈军 +1 位作者 刘伟 杨勇 《Journal of Beijing Institute of Technology》 EI CAS 2002年第3期234-239,共6页
An initial alignment technique for the strapdown inertial navigation system (SINS) of vehicles in the moving state is researched. By selecting an odometer as the system’s external sensor, the mathematical model for t... An initial alignment technique for the strapdown inertial navigation system (SINS) of vehicles in the moving state is researched. By selecting an odometer as the system’s external sensor, the mathematical model for the alignment in the moving state is established and the observability of the system is analyzed. The results show that the SINS can successfully achieve the precision alignment in 10 min when the vehicle is moving toward the prearranged place after its staying for several seconds to perform the coarse alignment. The precision of alignment can also be improved in the moving state compared with that in the static state. 展开更多
关键词 strapdown inertial navigation system initial alignment Kalman filter
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Device Robust-Design by Using Response Surface Methodology
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作者 谢晓锋 鲁勇 +1 位作者 张文俊 杨之廉 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2002年第8期817-824,共8页
Device robust-design is inherently a multiple-objective optimization problem.Using design of experiments (DoE) combined with response surface methodology (RSM) can satisfy the great incentive to reduce the number of t... Device robust-design is inherently a multiple-objective optimization problem.Using design of experiments (DoE) combined with response surface methodology (RSM) can satisfy the great incentive to reduce the number of technology CAD(TCAD) simulations that need to be performed.However,the errors of RSM models might be large enough to diminish the validity of the results for some nonlinear problems.To find the feasible design space,a new method with objectives-oriented design in generations that takes the errors of RSM model into account is presented.After the augment design of experiments in promising space according to the results of RSM model in current generation,the feasible space will be emerging as the model errors deceasing.The results on FIBMOS examples show that the methodology is efficient. 展开更多
关键词 response surface methodology design of experiments device robust-design
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MONTE CARLO SIMULATION OF RADIATION FIELD OPTIMIZATION FOR MEDICAL LINAC 被引量:2
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作者 赵洪斌 张新 +2 位作者 包尚联 黄斐增 李泉凤 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2010年第1期7-12,共6页
A method for designing an X-ray flatness filter for medical electron linac is developed. It is used in the optimization process in the electron beam radiation system. Monte Carlo simulation method is used and two exam... A method for designing an X-ray flatness filter for medical electron linac is developed. It is used in the optimization process in the electron beam radiation system. Monte Carlo simulation method is used and two examples of real radiation system optimization processes for China-made medical electron linac are provided: 15 MV X- ray system of BJ-20 linac, and 12 MeV electron system of BJ-14. Results are verified by using the traditional method. 展开更多
关键词 linear accelerators computer simulation and Monte Carlo methods radiation system optimization flatness filter design
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Maneuvering target tracking using threshold interacting multiple model algorithm
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作者 徐迈 山秀明 徐保国 《Journal of Southeast University(English Edition)》 EI CAS 2005年第4期440-444,共5页
To avoid missing track caused by the target maneuvers in automatic target tracking system, a new maneuvering target tracking technique called threshold interacting multiple model (TIMM) is proposed. This algorithm i... To avoid missing track caused by the target maneuvers in automatic target tracking system, a new maneuvering target tracking technique called threshold interacting multiple model (TIMM) is proposed. This algorithm is based on the interacting multiple model (IMM) method and applies a threshold controller to improve tracking accuracy. It is also applicable to other advanced algorithms of IMM. In this research, we also compare the position and velocity root mean square (RMS) errors of TIMM and IMM algorithms with two different examples. Simulation results show that the TIMM algorithm is superior to the traditional IMM alzorithm in estimation accuracy. 展开更多
关键词 maneuvering target tracking Kalman filter interacting multiple model (IMM) threshold interacting multiple model (TIMM)
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Application and optimization design of non-obstructive particle damping-phononic crystal vibration isolator in viaduct structure-borne noise reduction
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作者 SHI Duo-jia ZHAO Cai-you +3 位作者 ZHANG Xin-hao ZHENG Jun-yuan WEI Na-chao WANG Ping 《Journal of Central South University》 SCIE EI CAS CSCD 2024年第7期2513-2531,共19页
The problems associated with vibrations of viaducts and low-frequency structural noise radiation caused by train excitation continue to increase in importance.A new floating-slab track vibration isolator-non-obstructi... The problems associated with vibrations of viaducts and low-frequency structural noise radiation caused by train excitation continue to increase in importance.A new floating-slab track vibration isolator-non-obstructive particle damping-phononic crystal vibration isolator is proposed herein,which uses the particle damping vibration absorption technology and bandgap vibration control theory.The vibration reduction performance of the NOPD-PCVI was analyzed from the perspective of vibration control.The paper explores the structure-borne noise reduction performance of the NOPD-PCVIs installed on different bridge structures under varying service conditions encountered in practical engineering applications.The load transferred to the bridge is obtained from a coupled train-FST-bridge analytical model considering the different structural parameters of bridges.The vibration responses are obtained using the finite element method,while the structural noise radiation is simulated using the frequency-domain boundary element method.Using the particle swarm optimization algorithm,the parameters of the NOPD-PCVI are optimized so that its frequency bandgap matches the dominant bridge structural noise frequency range.The noise reduction performance of the NOPD-PCVIs is compared to the steel-spring isolation under different service conditions. 展开更多
关键词 non-obstructive particle damping phononic crystal vibration isolator band gap optimization floating-slab track bridge structure-borne noise control particle swarm optimization
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Speed Sensorless Vector Control of Induction Motor Based on Reduced Order Extended Kalman Filter 被引量:1
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作者 杨文强 贾正春 许强 《Journal of Southeast University(English Edition)》 EI CAS 2001年第1期41-45,共5页
A speed sensorless vector control system of induction motor with estimated rotor speed and rotor flux using a new reduced order extended Kalman filter is proposed. With this method, two rotor flux components are sele... A speed sensorless vector control system of induction motor with estimated rotor speed and rotor flux using a new reduced order extended Kalman filter is proposed. With this method, two rotor flux components are selected as the state variables, and the rotor speed as an estimated parameter is regarded as an augmented state variable. The algorithm with reduced order decreases the computational complexity and makes the proposed estimator feasible to be implemented in real time. The simulation results show high accuracy of the estimation algorithm and good performance of speed control, and verify the usefulness of the proposed algorithm. 展开更多
关键词 extended Kalman filter flux estimation speed estimation speed sensorless vector control induction motor
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Sea water temperature auto-monitoring system based on general packet radio service (GPRS) 被引量:1
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作者 张文孝 高国栋 慕关羽 《Agricultural Science & Technology》 CAS 2006年第3期13-18,共6页
This paper introduces the design and implementation of sea-water temperature auto-monitoring system based on General Packet Radio Service (GPRS). This system integrates modern wireless communication technology, the ... This paper introduces the design and implementation of sea-water temperature auto-monitoring system based on General Packet Radio Service (GPRS). This system integrates modern wireless communication technology, the signal gathering technology and computer network technology. MSC1210 microcontroller is used in data collection device in order to make system accurate and fast. In addition, wireless and Internet technologies are used for transferring and displaying collected field data. A prototype system has been completed and tested in field trials. The results proved the feasibility and usefulness of this system for monitoring the temperature. By using this system, a lot of resources and money can be saved. 展开更多
关键词 SENSOR MSC1210 GPRS remote monitor
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ATTITUDE MEASUREMENT ON HIGH-SPINNING PROJECTILE USING MAGNETIC SENSORS AND ACCELEROMETERS 被引量:5
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作者 李玎 卜雄洙 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2008年第2期106-112,共7页
In allusion to the limitations of the traditional attitude measurement system consisting of a three-axis magnetic sensor and two accelerometers on high-spinning projectile, a new scheme comprised of two magnetic senso... In allusion to the limitations of the traditional attitude measurement system consisting of a three-axis magnetic sensor and two accelerometers on high-spinning projectile, a new scheme comprised of two magnetic sensors and two accelerometers installed in a particular way is given. The configuration of the sensors is described. The calculation method and the mathematical model of the projectile attitude based on the sensor configuration are discussed. The basic calculation method including the Magsonde Window, the proof of the ratios of maximums and minimums and the calculation of the attitude angles are analyzed in theory. Finally, the system is simulated under the given conditions. The simulation result indicates that the estimated attitude angles are in agreement with the true attitude angles. 展开更多
关键词 PROJECTILE MAGNETOMETERS accelerometers attitude solution digital simulation
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High-performance channel estimation and compensation scheme for OFDMreceivers with IQ imbalances 被引量:1
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作者 束锋 童娟娟 +3 位作者 李隽 王进 顾晨 陆锦辉 《Journal of Southeast University(English Edition)》 EI CAS 2014年第4期416-421,共6页
A pilot pattern across two orthogonal frequency division multiplexing OFDM symbols with a special structure is designed for the channel estimation of OFDM systems with inphase and quadrature IQ imbalances at the recei... A pilot pattern across two orthogonal frequency division multiplexing OFDM symbols with a special structure is designed for the channel estimation of OFDM systems with inphase and quadrature IQ imbalances at the receiver.A high-efficiency time-domain TD least square LS channel estimator and a low-complexity frequency-domain Gaussian elimination GE equalizer are proposed to eliminate IQ distortion.The former estimator can significantly suppress channel noise by a factor N/L+1 over the existing frequency-domain FD LS where N and L+1 are the total number of subcarriers and the length of cyclic prefix and the proposed GE requires only 2N complex multiplications per OFDM symbol.Simulation results show that by exploiting the TD property of the channel the proposed TD-LS channel estimator obtains a significant signal-to-noise ratio gain over the existing FD-LS one whereas the proposed low-complexity GE compensation achieves the same bit error rate BER performance as the existing LS one. 展开更多
关键词 inphase and quadrature IQ imbalance equalizer channel estimation time domain frequency domain least square
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法定浓度计及使用这些仪器的标准分析方法
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《中国环境监测》 CAS CSSCI CSCD 北大核心 1992年第6期3-19,共17页
2.1关于法定浓度计:计量法施行令(昭和47年政令第151号)及其修订本(昭和53年政令第394号)中规定的浓度计有以下20种类型。 (1)浮称型浓度计;(2)电化学分析浓度计:a、电位差式浓度计,b、电导式浓度计,c、极谱仪,d、电量式浓度计,e、离子... 2.1关于法定浓度计:计量法施行令(昭和47年政令第151号)及其修订本(昭和53年政令第394号)中规定的浓度计有以下20种类型。 (1)浮称型浓度计;(2)电化学分析浓度计:a、电位差式浓度计,b、电导式浓度计,c、极谱仪,d、电量式浓度计,e、离子选择电极式浓度计,f、原电池式浓度计,g、接触燃烧式浓度计,h、氢火焰离子化式浓度计;(3)磁式浓度计;(4)光学分析式浓度计:a、分光光度计,b、火焰光度计,c、原子吸收分光光度计,d、比色计(包括光电比色计),e、光散射式浓度计,f、紫外线式浓度计,g、非分散型红外线式浓度计,h、化学发光式浓度计;(5)放射线式浓度计;(6)气相色谱仪。 展开更多
关键词 浓度计 分光光度法 计器 火焰原子吸收法 满刻度 标准分析方法 光度滴定法 PH计 自动检测器 通则
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A FAST KALMAN FILTER FOR INTEGRATED GPS/INS BASED ON U-D FACTORIZATION
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作者 何秀凤 陈永奇 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 1998年第2期8-13,共6页
A fast U D factorization based Kalman filter for the 21 state integrated global positioning system and inertial navigation system (GPS/INS) is developed from the point of engineering implementation. The conventio... A fast U D factorization based Kalman filter for the 21 state integrated global positioning system and inertial navigation system (GPS/INS) is developed from the point of engineering implementation. The conventional Kalman filter is widely used for integration of GPS/INS, however, due to the model and numerical computation errors, the Kalman filter may diverge in engineering implementation. In order to solve this problem, an extended Kalman filter based on the U D factorization is proposed. Moreover, the high order integrated system suffers from the problem of long computation time, leading to difficulties in real time applications. An algorithmic approach is developed to improve the computational speed. A typical aircraft trajectory is simulated to compare the improvement in the computational speed and the navigation accuracy using the conventional Kalman filter and the fast Kalman filter based on the U D factorization. The results indicate that the methods proposed in this paper are very effective in overcoming these problems for the high dynamic integrated GPS/INS system. 展开更多
关键词 GPS INS Kalman filter computer simulation
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A Low-Power-Consumption 9bit 10MS/s Pipeline ADC for CMOS Image Sensors 被引量:1
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作者 朱天成 姚素英 李斌桥 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2007年第12期1924-1929,共6页
A low-power-consumption 9bit 10MS/s pipeline ADC,used in a CMOS image sensor,is proposed. In the design, the decrease of power consumption is achieved by applying low-power-consumption and large-output-swing amplifier... A low-power-consumption 9bit 10MS/s pipeline ADC,used in a CMOS image sensor,is proposed. In the design, the decrease of power consumption is achieved by applying low-power-consumption and large-output-swing amplifiers with gain boost structure, and biasing all the cells with the same voltage bias source, which requires careful layout design and large capacitors. In addition,capacitor array DAC is also applied to reduce power consumption,and low threshold voltage MOS transistors are used to achieve a large signal processing range. The ADC was implemented in a 0.18μm 4M-1 P CMOS process,and the experimental results indicate that it consumes only 7mW, which is much less than general pipeline ADCs. The ADC was used in a 300000 pixels CMOS image sensor. 展开更多
关键词 pipeline ADC low power design CMOS image sensor large signal processing range
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DESIGN & REALIZATION ON GPS/INS INTEGRATED NAVIGATION SYSTEM 被引量:1
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作者 刘建业 孙永荣 +1 位作者 何秀凤 袁信 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 1998年第2期14-20,共7页
This paper deals with the research of the GPS/INS integrated navigation system applying Extended Kalman Filter, which involves integrated principles, scheme and technology of combining with real INS and GPS receiver d... This paper deals with the research of the GPS/INS integrated navigation system applying Extended Kalman Filter, which involves integrated principles, scheme and technology of combining with real INS and GPS receiver data. Emphases are placed on the modeling of system errors and implementation of the integrated system. Both loose and tightly coupled GPS/INS integrated in schemes are analyzed. On the basis of our experience accumulated in the research of GPS/INS for many years, the GPS/INS integrated navigation developing system is developed. It can be put into efficient and economic use in the study and design of integrated navigation system. It plays an important role in the aeronautical and astronautical fields in China. This system is not only a computer aided design software but also a semi physical simulation system by obtaining real INS and GPS receiver data. So the key software unit of the developing system could be conveniently transferred into practical engineering software in actual hardware integrated system. The application of this system shows that the design ideas and integrated scheme of this development system are successful, and can achieve good navigation result. 展开更多
关键词 integrated navigation system inertial navigation Kalman filter navigation computer GPS
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Structural design and experimental research of microwave radiation heater for asphalt pavements 被引量:2
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作者 朱松青 史金飞 《Journal of Southeast University(English Edition)》 EI CAS 2009年第1期68-73,共6页
In order to improve the efficiency of heating and the uniformity of temperature distribution in recycling asphalt mixtures, a pyramidal radiation heater is designed. The principles of designing horn surface size and a... In order to improve the efficiency of heating and the uniformity of temperature distribution in recycling asphalt mixtures, a pyramidal radiation heater is designed. The principles of designing horn surface size and antenna length are established according to the law of energy conservation and microwave antenna radiation theory. Modeling and simulation are carried out using IE3D software. The simulation results demonstrate that, with a fixed horn surface size, the shortened electric antenna length is the main factor leading to the improved heating uniformity. On the other hand, with a fixed antenna length and diminished surface size, the standing wave ratio decreases with the improved radiation efficiency. Furthermore, the efficiency of radiation drops with increased distance between the horn surface and the asphalt pavement. Microwave heating experiments are carried out using this type of heater. The temperature distribution of asphalt samples is obtained by the grid temperature measurement method, and Matlab simulation is performed. The experimental results are in good agreement with the simulation. 展开更多
关键词 asphalt mixtures microwave heating temperature distribution microwave radiation heater structural design
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A Novel Analytical Model for Surface Electrical Field Distribution and Optimization of TFSOI RESURF Devices 被引量:1
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作者 何进 张兴 +1 位作者 黄如 王阳元 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2001年第4期402-408,共7页
A novel analytical model for the thin film silicon on insulator (TFSOI) reduced surface field (RESURF) devices has been proposed.Based on the 2-D Poisson equation solution,the analytical expressions for the surface po... A novel analytical model for the thin film silicon on insulator (TFSOI) reduced surface field (RESURF) devices has been proposed.Based on the 2-D Poisson equation solution,the analytical expressions for the surface potential and field distributions are derived.From this analysis,the optimum design condition for the maximum breakdown voltage is obtained.The dependence of the maximum breakdown voltage on the drift region length is examined and the relationship between the critical doping concentration and the front- and back- interface oxide layer thickness is discussed.The numerical simulation performed by the advanced semiconductor simulation tool,DESSIS-ISE,has been shown to support the analytical results. 展开更多
关键词 TFSOI RESURF devices surface electric field distribution potential profile breakdown voltage optimum design
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OPTIMIZATION OF AIRPORT TAXIING PLANNING DURING CONGESTED HOURS BASED ON IMMUNE CLONAL SELECTION ALGORITHM 被引量:1
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作者 柳青 吴桐水 宋祥波 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2012年第3期294-301,共8页
In order to ease congestion and ground delays in major hub airports, an aircraft taxiing scheduling optimization model is proposed with schedule time as the object function. In the new model, the idea of a classical j... In order to ease congestion and ground delays in major hub airports, an aircraft taxiing scheduling optimization model is proposed with schedule time as the object function. In the new model, the idea of a classical job shop-schedule problem is adopted and three types of special aircraft-taxi conflicts are considered in the constraints. To solve such nondeterministic polynomial time-complex problems, the immune clonal selection algorithm(ICSA) is introduced. The simulation results in a congested hour of Beijing Capital International Airport show that, compared with the first-come-first-served(FCFS) strategy, the optimization-planning strategy reduces the total scheduling time by 13.6 min and the taxiing time per aircraft by 45.3 s, which improves the capacity of the runway and the efficiency of airport operations. 展开更多
关键词 aircraft taxiing schedule airport operation control hub airport congested hours immune clonal selection algorithm(ICSA)
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Study on Blade Mould CAD/CAM for Hydrodynamic Torque COnverters
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作者 项昌乐 阎清东 吕红梅 《Journal of Beijing Institute of Technology》 EI CAS 1998年第2期172-177,共6页
Aim To develop blade mould CAD/CAM system of torque converter. Methods The mouldconsisted of four parts and an interactive computer program was developed to design a blade mould of torque converter based on UG at wor... Aim To develop blade mould CAD/CAM system of torque converter. Methods The mouldconsisted of four parts and an interactive computer program was developed to design a blade mould of torque converter based on UG at workstation. Results As compar- ed to manual modeling, it is showed in the application that this means not only improves the accuracy of blade shape and manufacture efficiency of converter, but also reduces costs. Conclusion It is proved that this CAD/CAM system is successful, and it opens up widely prospects for design and manufacture of the blade elementsand their moulds. 展开更多
关键词 hydrodynamic torque converter MOULD CAD /CAM
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