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论行为管理手段的“四制”关系 被引量:1
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作者 陈蛇 陈朝龙 《西南交通大学学报(社会科学版)》 2006年第1期105-108,共4页
管理行为不同层次的矛盾有其特殊性,可以选择不同的方法加以解决。制度在行为管理手段中有其适用范围,此外,机制、“人制”、自制也是行为管理的另外三种有效手段,这四种行为管理手段有着各自的特点和适用范围,有鉴别地应用好这四种行... 管理行为不同层次的矛盾有其特殊性,可以选择不同的方法加以解决。制度在行为管理手段中有其适用范围,此外,机制、“人制”、自制也是行为管理的另外三种有效手段,这四种行为管理手段有着各自的特点和适用范围,有鉴别地应用好这四种行为管理手段,可以有效地解释行为管理的现象,并可指导行为管理实践。 展开更多
关键词 “人制”
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关于航天工业实施“人制管理”的思考
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作者 夏国洪 《航天工业管理》 2001年第5期3-8,共6页
关键词 航天工业 “人制管理” 管理创新 企业
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Deep learning models semi-automatic training system for quality control of transthoracic echocardiography
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作者 QIAN Sunnan WENG Hexiang +7 位作者 CHENG Hanlin SHI Zhongqing WANG Xiaoxian GUO Guanjun FANG Aijuan LUO Shouhua YAO Jing QI Zhanru 《中国医学影像技术》 CSCD 北大核心 2024年第8期1140-1145,共6页
Objective To explore the value of deep learning(DL)models semi-automatic training system for automatic optimization of clinical image quality control of transthoracic echocardiography(TTE).Methods Totally 1250 TTE vid... Objective To explore the value of deep learning(DL)models semi-automatic training system for automatic optimization of clinical image quality control of transthoracic echocardiography(TTE).Methods Totally 1250 TTE videos from 402 patients were retrospectively collected,including 490 apical four chamber(A4C),310 parasternal long axis view of left ventricle(PLAX)and 450 parasternal short axis view of great vessel(PSAX GV).The videos were divided into development set(245 A4C,155 PLAX,225 PSAX GV),semi-automated training set(98 A4C,62 PLAX,90 PSAX GV)and test set(147 A4C,93 PLAX,135 PSAX GV)at the ratio of 5∶2∶3.Based on development set and semi-automatic training set,DL model of quality control was semi-automatically iteratively optimized,and a semi-automatic training system was constructed,then the efficacy of DL models for recognizing TTE views and assessing imaging quality of TTE were verified in test set.Results After optimization,the overall accuracy,precision,recall,and F1 score of DL models for recognizing TTE views in test set improved from 97.33%,97.26%,97.26%and 97.26%to 99.73%,99.65%,99.77%and 99.71%,respectively,while the overall accuracy for assessing A4C,PLAX and PSAX GV TTE as standard views in test set improved from 89.12%,83.87%and 90.37%to 93.20%,90.32%and 93.33%,respectively.Conclusion The developed DL models semi-automatic training system could improve the efficiency of clinical imaging quality control of TTE and increase iteration speed. 展开更多
关键词 ECHOCARDIOGRAPHY quality control artificial intelligence
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Improved YOLOv8-Based Target Detection Algorithm for UAV Aerial Image
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作者 JIANG Mao-xiang SI Zhan-jun 《印刷与数字媒体技术研究》 CAS 北大核心 2024年第4期86-96,共11页
In response to the challenge of low detection accuracy and susceptibility to missed and false detections of small targets in unmanned aerial vehicles(UAVs)aerial images,an improved UAV image target detection algorithm... In response to the challenge of low detection accuracy and susceptibility to missed and false detections of small targets in unmanned aerial vehicles(UAVs)aerial images,an improved UAV image target detection algorithm based on YOLOv8 was proposed in this study.To begin with,the CoordAtt attention mechanism was employed to enhance the feature extraction capability of the backbone network,thereby reducing interference from backgrounds.Additionally,the BiFPN feature fusion network with an added small object detection layer was used to enhance the model's ability to perceive for small objects.Furthermore,a multi-level fusion module was designed and proposed to effectively integrate shallow and deep information.The use of an enhanced MPDIoU loss function further improved detection performance.The experimental results based on the publicly available VisDrone2019 dataset showed that the improved model outperformed the YOLOv8 baseline model,mAP@0.5 improved by 20%,and the improved method improved the detection accuracy of the model for small targets. 展开更多
关键词 UAV YOLOv8 Attentional mechanisms Multi-scale detection MPDIoU
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GUIDANCE AND CONTROL FOR AUTOMATIC LANDING OF UAV 被引量:1
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作者 曹云峰 陶勇 沈勇璋 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2001年第2期229-235,共7页
A scheme of guidance and control is presented to meet the requirements for automatic landing of unmanned aerial vehicles (UAVs) based on the airborne digital flight control system and radio tracker on ground station. ... A scheme of guidance and control is presented to meet the requirements for automatic landing of unmanned aerial vehicles (UAVs) based on the airborne digital flight control system and radio tracker on ground station. An automatic landing system is realized for an unmanned aerial vehicle. The results of real time simulation and flight test are given to illustrate the effectiveness and availability of the scheme. Results meet all the requirements for automatic landing of the unmanned aerial vehicle. 展开更多
关键词 automatic landing unmanned aerial vehicle GUIDANCE NAVIGATION flight control
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Force assistant master-slave telerehabilitation robotic system 被引量:4
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作者 李会军 宋爱国 《Journal of Southeast University(English Edition)》 EI CAS 2008年第1期42-45,共4页
A prototype of the master slave telerehabilitation robotic system with force feedback is developed. This system contains a pair of robots with the master being operated by the therapist and the slave following the mas... A prototype of the master slave telerehabilitation robotic system with force feedback is developed. This system contains a pair of robots with the master being operated by the therapist and the slave following the master to guide the patients to exercise. A slave device with a slave controller is designed to stretch and mobilize the impaired elbow joints accurately and safely. A master device with a master controller is designed to control/monitor the procedure of treatment and assess the outcome of treatment remotely and accurately. By using the twoport network theory and the circuit equivalent impedance models, the position-force control scheme is designed to generate force feedback for the therapist who is to be informed of the interaction force between the subject and the robot arm during exercise. Experiments were conducted with a healthy male. Results show that the therapist can guide the patient to exercise by the master arm and can feel the interaction forces between the impaired arm and the robot. Compared with the traditional therapy, this system is more cost-efficient, more convenient and safer for both the stroke patients and the clinicians. 展开更多
关键词 TELEREHABILITATION force feedback ROBOT positionforce control scheme
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FUZZY ADAPTIVE CONTROL OF FLEXIBLE-LINK ROBOT MANIPULATOR 被引量:1
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作者 倪受东 吴洪涛 +1 位作者 袁祖强 嵇海平 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2004年第3期200-205,共6页
A fuzzy adaptive control method is proposed for a flexible robot manipulator. Due to the structure characteristics of the flexible manipulator, the vibration modes must be controlled to realize the high-precision tip ... A fuzzy adaptive control method is proposed for a flexible robot manipulator. Due to the structure characteristics of the flexible manipulator, the vibration modes must be controlled to realize the high-precision tip position. The Lagrangian principle is utilized to model the dynamic function of the single-degree flexible manipulator incorporating the assumed modes method. Simulation results of the fuzzy adaptive control method in the location control and the trajectory tracking with different tip disturbances are presented and compared with the results of the classic PD control. It shows that the controller can obtain the stable and robust performance. 展开更多
关键词 flexible robot manipulator Lagrangian function assumed mode method fuzzy adaptive control
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NEW METHOD FOR SAFETY ASSESSMENT OF PARALLEL ROUTES 被引量:1
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作者 隋东 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2009年第1期36-43,共8页
A new safety assessment method for parallel routes is presented. From the aspects of safety guard system of air traffic control(ATC) and considering the flight conflict as causing event of air collision accidents, t... A new safety assessment method for parallel routes is presented. From the aspects of safety guard system of air traffic control(ATC) and considering the flight conflict as causing event of air collision accidents, this paper fosters a four-layer safety guard of controller command, short-term conflict alerts (STCAs), pilot visual avoidance, and traffic alert collision avoidance system(TCAS). Then, the problem of parallel routes collision risk is divided into two parts:the calculation of potential flight conflict and the analysis of failure probability of the four-layer safety guard. A calculation model for controller interference times is induced. By using cognitive reliability and error analysis method(CREAM),the calculation problem to failure probability of controller sequencing flight conflicts is solved and a fault tree model of guard failure of STCA and TCAS is established. Finally, the Beijing-Shanghai parallel routes are taken as an example to be calculated and the collision risk of the parallel routes is obtained under the condition of radar control. Results show that the parallel routes can satisfy the safety demands. 展开更多
关键词 air traffic control human factors safety assessment short-term conflict alerts traffic alert collision avoidance system
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FUZZY COORDINATION AND FORCE/POSITION CONTROL OF ROBOTIC MANIPULATOR
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作者 乔兵 尉忠信 朱剑英 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 1999年第1期55-60,共6页
It is crucial for implementing force/position control of robotic manipulator under the constraint of unknown environment to determine the force control and the position control directions. This paper presents an on l... It is crucial for implementing force/position control of robotic manipulator under the constraint of unknown environment to determine the force control and the position control directions. This paper presents an on line algorithm to real timely estimate the tangent and the normal vectors of the constraint surface based on the measured contact force under the consideration of frictional force. A fuzzy synthesis policy is proposed to coordinate the conflict between the compliant force control and the stiff position control. An experimental study on an AdeptThree, a SCARA type robotic manipulator, is conducted. The experimental results show that the policy presented in the paper is effective. 展开更多
关键词 robotic manipulator force/position control CONSTRAINTS COORDINATION fuzzy synthesis
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On Structure,production,and market of bamboo-based panels in China 被引量:23
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作者 蒋身学 张齐生 姜树海 《Journal of Forestry Research》 SCIE CAS CSCD 2002年第2期151-156,165,共6页
Since bamboo has the advantages of straight grain, beautiful color, high strength and toughness, and excellent abrasion resistance, bamboo-based panels have been widely used in the fields of vehicle, construction, shi... Since bamboo has the advantages of straight grain, beautiful color, high strength and toughness, and excellent abrasion resistance, bamboo-based panels have been widely used in the fields of vehicle, construction, ship building, furniture, and decoration to partly take the place of wood, steel, plastic etc in China. This paper briefly described the basic component units, including strip, sliver, and particle, of bamboo-based panel and pointed out that to design the structure of bamboo-based panels should follow the principle of symmetric structure, surface forming method, and structuring principle of equalizing stress. According to the processing methods and formation of component units, the authors classified the bamboo-based panels in China into 13 types and presented the manufacturing technique and uses of the bamboo products, such as plybamboo, bamboo flooring, and bamboo-wood composite products in detail. In the last part of the paper, much information were offered on the output, market, and selling prospect of each type of bamboo-based panels. 展开更多
关键词 Bamboo-based panel Component units STRUCTURE Production process MARKET
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An adaptive switching control approach for trajectory tracking of robotic manipulators 被引量:1
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作者 杨振 费树岷 +2 位作者 王芳 鲍安平 刘顾全 《Journal of Southeast University(English Edition)》 EI CAS 2016年第2期183-186,共4页
In order to design a suitable controller which can achieve accurate trajectory tracking and a good control performance, and guarantee the stability and robustness of a robot system due to external disturbances error a... In order to design a suitable controller which can achieve accurate trajectory tracking and a good control performance, and guarantee the stability and robustness of a robot system due to external disturbances error and internal parameter variations, an adaptive switching control strategy is proposed. The proposed scheme is designed under the condition of bounded distances and consists of an adaptive switching law and a PD controller. Based on the Lyapunov stability theory, it is proved that the proposed scheme can guarantee the tracking performance of the robotic manipulator and is adapted to varying unknown loads. Simulations are carded out on a two-link robotic manipulator, which illustrate the feasibility and validity of the proposed control scheme and the robustness for variational payloads. 展开更多
关键词 adaptive control switch control roboticmanipulator trajectory tracking
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IMPROVED PARTICLE SWARM OPTIMIZATION ALGORITHM FOR INTELLIGENTLY SETTING UAV ATTITUDE CONTROLLER PARAMETERS
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作者 浦黄忠 甄子洋 +1 位作者 王道波 胡勇 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2009年第1期52-57,共6页
An improved particle swarm optimization (PSO) algorithm is investigated in the optimization of the attitude controller parameters of unmanned aerial vehicle (UAV). Considering the stagnation phenomenon in the late... An improved particle swarm optimization (PSO) algorithm is investigated in the optimization of the attitude controller parameters of unmanned aerial vehicle (UAV). Considering the stagnation phenomenon in the later phase of the basic PSO algorithm caused by the diversity scarcity of particles, a modified PSO algorithm is presented. For the basic PSO algorithm, the velocity of each particle is adjusted according to the inertia motion, the swarm previous best position and its own previous best position. However, in the improved PSO algorithm, each particle only learns from another randomly selected particle with higher performance, besides keeping the inertia motion. The inertia weight of the improved PSO algorithm is a random number. The modification decreases the uncertain parameters of the algorithm, simplifies the learning mechanism of the particle, and enhances the diversity of the swarm. Furthermore, a UAV attitude control system is built, and the improved PSO algorithm is applied in the optimized tuning of four controller parameters. Simulation results show that the improved PSO algorithm has stronger global searching ability than the common PSO algorithms, and obtains better UAV attitude control parameters. 展开更多
关键词 unmanned aerial vehicle attitude control particle swarm optimization
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Question and Countermeasure Research of Human Living Environment Designs in New Countries 被引量:1
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作者 王影 《Agricultural Science & Technology》 CAS 2010年第6期134-136,154,共4页
In the view of new rural living environment,problems existing in the construction of current new rural living environment were analyzed so as to propose some theoretical ideas and ways for resolving the problems exist... In the view of new rural living environment,problems existing in the construction of current new rural living environment were analyzed so as to propose some theoretical ideas and ways for resolving the problems existing in the design of new rural living environment. 展开更多
关键词 Living environment layout Adjust measures to local conditions INFRASTRUCTURE
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A novel algorithm of normal attitude regulation for the designed end-effector of a flexible drilling robot 被引量:5
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作者 张来喜 王兴松 《Journal of Southeast University(English Edition)》 EI CAS 2012年第1期29-34,共6页
An end-effector for a flexible drilling robot is designed, and a novel four-point algorithm of normal attitude regulation for this end-effector is presented. Four non-coplanar points can define a unique sphere tangent... An end-effector for a flexible drilling robot is designed, and a novel four-point algorithm of normal attitude regulation for this end-effector is presented. Four non-coplanar points can define a unique sphere tangent to them in spatial geometry, and the center point of the sphere and the radius can be calculated. The shape of a workpiece surface in the machining area is approximately regarded as such a sphere. A vector from the machining point to the center point is thus approximately regarded as a normal vector to the workpiece surface. By this principle, the algorithm first measures four coordinates on the curve in the drilling region using four sensors and calculates the normal vector at the drilling point, then calculates the error between the normal vector and the axis of the spindle. According to this error, the algorithm further figures out the angles of two revolving axes on the end- effector and the displacements of three linear axes on the robot main body, thus it implements the function of adjusting the spindle to be perpendicular to the curve at the drilling point. Simulation results of two kinds of curved surfaces show that accuracy and efficiency can be realized using the proposed algorithm. 展开更多
关键词 four-point position regulation END-EFFECTOR flexible drilling robot drilling machining on curved surface
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Cloning and Expression Analysis of a Human Putative Tumor Suppressor Gene Homologue from Rice
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作者 葛晓春 宗晖 +3 位作者 詹树萱 陈继超 孙崇荣 曹凯鸣 《Acta Botanica Sinica》 CSCD 2002年第5期562-566,共5页
A gene homologous to the human Putative tumor suppressor gone QM, designated OSQM1, was isolated from rice (Oryza sativa L.) genomic DNA library using through homology screening. It contained 4 exons and 3 introns, en... A gene homologous to the human Putative tumor suppressor gone QM, designated OSQM1, was isolated from rice (Oryza sativa L.) genomic DNA library using through homology screening. It contained 4 exons and 3 introns, encoding a protein of 219 amino acids with 46 basic amino acids, leading to a high isoelectric point of 11.02. Homology search showed that this gene existed in eukaryotes and highly conserved throughout eukaryotes, suggesting an essential role of this gene. Northern Not analysis showed that it was expressed in various rice organs, but at lower level in developing flower and callus tissue than in other vegetative organs. Its expression levels in roots and leaves were influenced by different environmental factors. 展开更多
关键词 tumor suppressor gene QM EUKARYOTES
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The Role of Predominant Expression of Th2 Type Cytokines Gene in the Genesis and Development of Human Gliomas 被引量:1
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作者 李刚 胡永生 +3 位作者 李新钢 张庆林 贾德泽 宫崧峰 《The Chinese-German Journal of Clinical Oncology》 CAS 2003年第4期227-230,252,253,共6页
Objective: To explore the expression of Th1/Th2 cytokines gene in human gliomas and its role in the genesis and development of human gliomas.Methods: Using IL-2 and IFNγ as Th1 type cytokines, IL-4, IL-6 and IL-10 as... Objective: To explore the expression of Th1/Th2 cytokines gene in human gliomas and its role in the genesis and development of human gliomas.Methods: Using IL-2 and IFNγ as Th1 type cytokines, IL-4, IL-6 and IL-10 as Th2 type cytokines, the biological activity of cytokines in the supernatant of glioma cell lines was assayed by ELISA method, and the gene expression of Th1/Th2 cytokines in human glioma cells, glioma infiltrating lymphocytes and glioma cell lines were detected by RT-PCR.Results: There was predominant expression of Th2 type cytokines in human glioma cells, glioma infiltrating lymphocytes and glioma cell lines, but there was no such expression in normal brain tissues.Conclusion: It suggested that there is a relationship between the Th2 type cytokines expression in human gliomas and the immunosupressive status of human glioma patients. The predominant expression of Th2 type cytokines may play an important role in the genesis and development of human gliomas. Key words glioma - Th1/Th2 - gene expression - RT-PCR This project was supported by a grant from National Natural Sciences foundation of China (No. 30271335). 展开更多
关键词 GLIOMA TH1/TH2 gene expression RT-PCR
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Antibiotic Activity of Seven Fungicides against Alternaria panax Whetz 被引量:1
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作者 唐铭浩 张雪 +1 位作者 邢淑欢 李翔国 《Agricultural Science & Technology》 CAS 2016年第12期2862-2865,共4页
[Objective] This study was conducted to screen suitable fungicides to con-trol ginseng leaf blight caused by Alternaria panax_Whetz. [Method] The antifungal activity of seven fungicides against A. panax_ was determine... [Objective] This study was conducted to screen suitable fungicides to con-trol ginseng leaf blight caused by Alternaria panax_Whetz. [Method] The antifungal activity of seven fungicides against A. panax_ was determined based on mycelial growth rate in vitro. [Result] The results of in vitro antibiotic activity assay showed that there were significant differences in inhibition rate among different concentration treatments of each of the seven fungicides. Toxicity test results showed that among the seven fungicides, difenoconazole had the smal est EC50 (0.61 mg/L), fol owed by streptomycin and captan, with EC50 value lower than 100 mg/L. [Conclusion] A fungicide which had strong antifungal activity on A. panax was screened out, and the results wil provide a theoretical basis for further field trial. 展开更多
关键词 FUNGICIDE Alternaria panax Whetz Antibiotic activity
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Studies on gallstone in China 被引量:21
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作者 Jing-Sen Shi~1 Jing-Yun Ma~2 Li-Hong Zhu~2 Bo-Rong Pan~2 Zuo-Ren Wang~2 Lian-Sheng Ma~2 1 Research Laboratory of Hepato-biliary Surgery,First Hospital of Xi’an Jiaotong University2 The WJG Press,P.O.Box 2345,Beijing 100023,China 《World Journal of Gastroenterology》 SCIE CAS CSCD 2001年第5期593-596,共4页
INTRODCTlONGallstone is one of the common primary diseases of bile system. Chinese researchers have done comprehensive and thorough studies on it, but there are still some problems we have not solved. It is necessary ... INTRODCTlONGallstone is one of the common primary diseases of bile system. Chinese researchers have done comprehensive and thorough studies on it, but there are still some problems we have not solved. It is necessary to review the achievements we have made in this field recently, to summarize the experiences and find the tendency so as to provide a sound foundation for the researches in the new century. Due to the popularization of molecular biological research methods, a rapid development of modern imaging techniques and medical equipment, the basic and clinical studies of cholelithiasis have set foot on the fast lane. Studies on the cause of cholelithiasis formation and its prevention have covered areas from epidemiological investigation at macroscopical level to molecular biological researches at microcosmic level. Clinical studies include prevention and treatment of cholelithiasis with traditional Chinese medicine, popularization of micro-injury surgery,treatment of complicated calculus of bile duct, and other aspects. 展开更多
关键词 China CHOLELITHIASIS CONTROL Humans
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An improved artificial bee colony algorithm for steelmaking–refining–continuous casting scheduling problem 被引量:12
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作者 Kunkun Peng Quanke Pan Biao Zhang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2018年第8期1727-1735,共9页
Steelmaking–refining–Continuous Casting(SCC) scheduling is a worldwide problem, which is NP-hard. Effective SCC scheduling algorithms can help to enhance productivity, and thus make significant monetary savings. Thi... Steelmaking–refining–Continuous Casting(SCC) scheduling is a worldwide problem, which is NP-hard. Effective SCC scheduling algorithms can help to enhance productivity, and thus make significant monetary savings. This paper develops an Improved Artificial Bee Colony(IABC) algorithm for the SCC scheduling. In the proposed IABC, charge permutation is employed to represent the solutions. In the population initialization, several solutions with certain quality are produced by a heuristic while others are generated randomly. Two variable neighborhood search neighborhood operators are devised to generate new high-quality solutions for the employed bee and onlooker bee phases, respectively. Meanwhile, in order to enhance the exploitation ability, a control parameter is introduced to conduct the search of onlooker bee phase. Moreover, to enhance the exploration ability,the new generated solutions are accepted with a control acceptance criterion. In the scout bee phase, the solution corresponding to a scout bee is updated by performing three swap operators and three insert operators with equal probability. Computational comparisons against several recent algorithms and a state-of-the-art SCC scheduling algorithm have demonstrated the strength and superiority of the IABC. 展开更多
关键词 Artificial bee colony Steelmaking–refining–continuous casting Hybrid flowshop scheduling Variable neighborhood search
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Control for Intelligent Manufacturing: A Multiscale Challenge 被引量:7
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作者 Han-Xiong Li Haitao Si 《Engineering》 SCIE EI 2017年第5期608-615,共8页
The Made in China 2025 initiative will require full automation in all sectors, from customers to production. This will result in great challenges to manufacturing systems in all sectors. In the future of manufacturing... The Made in China 2025 initiative will require full automation in all sectors, from customers to production. This will result in great challenges to manufacturing systems in all sectors. In the future of manufacturing, all devices and systems should have sensing and basic intelligence capabilities for control and adaptation. In this study, after discussing multiscale dynamics of the modern manufacturing system, a five-layer functional structure is proposed for uncertainties processing. Multiscale dynamics include: multi-time scale, spacetime scale, and multi-level dynamics. Control action will differ at different scales, with more design being required at both fast and slow time scales. More quantitative action is required in low-level operations, while more qualitative action is needed regarding high-level supervision. Intelligent manufacturing systems should have the capabilities of flexibility, adaptability, and intelligence. These capabilities will require the control action to be distributed and integrated with different approaches, including smart sensing, optimal design, and intelligent learning. Finally, a typical jet dispensing system is taken as a real-world example for multiscale modeling and control. 展开更多
关键词 System modeling Process control Artificial intelligence MANUFACTURING Jet dispensing
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