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Determination of Monitoring Control Value for Concrete Gravity Dam Spatial Deformation Based on POT Model
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作者 Zhiwen Xie Tiantang Yu 《Computer Modeling in Engineering & Sciences》 SCIE EI 2023年第6期2119-2135,共17页
Deformation can directly reflect the working behavior of the dam,so determining the deformation monitoring control value can effectively monitor the safety of dam operation.The traditional dam deformation monitoring c... Deformation can directly reflect the working behavior of the dam,so determining the deformation monitoring control value can effectively monitor the safety of dam operation.The traditional dam deformation monitoring control value only considers the single measuring point.In order to overcome the limitation,this paper presents a new method to determine the monitoring control value for concrete gravity dam based on the deformations of multi-measuring points.A dam’s comprehensive deformation displacement is determined by the measured values at different measuring points on the positive inverted vertical line and the corresponding weight of eachmeasuring point.The projection pursuit method(PPM)combined with the grey wolf optimization(GWO)algorithm is used to determine the weight of each measuring point according to the spatial correlation distribution characteristics of dam deformation.The peaks over threshold(POT)model based on the extreme value theory is adopted to determine the monitoring control value with the obtained dam comprehensive deformation displacement.In addition,the POTmodel is improved with the automatic threshold determinationmethod based on the 3σcriterion in probability theory and the GWO algorithm,which can avoid subjectivity and randomness in determining the threshold.The results of the engineering application show the feasibility and applicability of the proposed method. 展开更多
关键词 Concrete gravity dam DEFORMATION monitoring control value PPM GWO POT
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Thinking about Value Realization of Ecological Products under the Background of Urban-rural Integration in Chengdu“Western Control”Area
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作者 ZHANG Xuequan ZHANG Yi 《Journal of Landscape Research》 2023年第2期59-62,共4页
Chengdu's development strategy of“western control”has laid a solid ecological background for 8 western districts,cities and counties and cultivated good ecological resources.The integrated urban-rural developmen... Chengdu's development strategy of“western control”has laid a solid ecological background for 8 western districts,cities and counties and cultivated good ecological resources.The integrated urban-rural development in the new era will realize the balanced development of urban and rural areas and give full play to the value of rural ecological resources through the“powerful combination”of urban and rural areas.To realize the urban-rural integration and high-quality rural development in Chengdu“western control”area,it is necessary to enhance the awareness of ecological resources and ecological products,and carry out unified planning of ecological infrastructure,ecological material products and ecological service products in the whole“western control”area.Meantime,ecological restoration must be carried out scientifically,and scene design for value transformation of ecological products should be implemented innovatively. 展开更多
关键词 Western control Urban-rural integration Ecological products Ecological value transformation
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Simulation Study on Heat Value Control System of Natural Gas Used for Color TV Tubes Production 被引量:1
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作者 郑斌 《Journal of Beijing Institute of Technology》 EI CAS 2006年第3期283-287,共5页
In order to know the character of the heat value control system, determine the influence of natural gas quality and flow on the heat value, and learn how to adjust the parameters of control system, the model of the wh... In order to know the character of the heat value control system, determine the influence of natural gas quality and flow on the heat value, and learn how to adjust the parameters of control system, the model of the whole system is established, and simulation of the system is adopted in Matlab/Simulink. The simulation result shows that the feedback system with feed-forward block controls the heat value very well, and the simulation result can effectively guide the engineering design of the heat value control system, and the efficiency of engineering is improved. 展开更多
关键词 natural gas heat value control system simulation
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An Upper Limit for Iterative Learning Control Initial Input Construction Using Singular Values 被引量:1
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作者 Naser Alajmi Ali Alobaidly +2 位作者 Mubarak Alhajri Salem Salamah Muhammad Alsubaie 《Intelligent Control and Automation》 2017年第3期154-163,共10页
Selecting a proper initial input for Iterative Learning Control (ILC) algorithms has been shown to offer faster learning speed compared to the same theories if a system starts from blind. Iterative Learning Control is... Selecting a proper initial input for Iterative Learning Control (ILC) algorithms has been shown to offer faster learning speed compared to the same theories if a system starts from blind. Iterative Learning Control is a control technique that uses previous successive projections to update the following execution/trial input such that a reference is followed to a high precision. In ILC, convergence of the error is generally highly dependent on the initial choice of input applied to the plant, thus a good choice of initial start would make learning faster and as a consequence the error tends to zero faster as well. Here in this paper, an upper limit to the initial choice construction for the input signal for trial 1 is set such that the system would not tend to respond aggressively due to the uncertainty that lies in high frequencies. The provided limit is found in term of singular values and simulation results obtained illustrate the theory behind. 展开更多
关键词 ITERATIVE Learning control INITIAL INPUT Selection SINGULAR valueS
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Series-parallel Hybrid Vehicle Control Strategy Design and Optimization Using Real-valued Genetic Algorithm 被引量:14
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作者 XIONG Weiwei YIN Chengliang ZHANG Yong ZHANG Jianlong 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2009年第6期862-868,共7页
Despite the series-parallel hybrid electric vehicle inherits the performance advantages from both series and parallel hybrid electric vehicle, few researches about the series-parallel hybrid electric vehicle have been... Despite the series-parallel hybrid electric vehicle inherits the performance advantages from both series and parallel hybrid electric vehicle, few researches about the series-parallel hybrid electric vehicle have been revealed because of its complex co nstruction and control strategy. In this paper, a series-parallel hybrid electric bus as well as its control strategy is revealed, and a control parameter optimization approach using the real-valued genetic algorithm is proposed. The optimization objective is to minimize the fuel consumption while sustain the battery state of charge, a tangent penalty function of state of charge(SOC) is embodied in the objective function to recast this multi-objective nonlinear optimization problem as a single linear optimization problem. For this strategy, the vehicle operating mode is switched based on the vehicle speed, and an "optimal line" typed strategy is designed for the parallel control. The optimization parameters include the speed threshold for mode switching, the highest state of charge allowed, the lowest state of charge allowed and the scale factor of the engine optimal torque to the engine maximum torque at a rotational speed. They are optimized through numerical experiments based on real-value genes, arithmetic crossover and mutation operators. The hybrid bus has been evaluated at the Chinese Transit Bus City Driving Cycle via road test, in which a control area network-based monitor system was used to trace the driving schedule. The test result shows that this approach is feasible for the control parameter optimization. This approach can be applied to not only the novel construction presented in this paper, but also other types of hybrid electric vehicles. 展开更多
关键词 series-parallel hybrid electric vehicle control strategy DESIGN OPTIMIZATION real-valued genetic algorithm
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Accuracy Assignment Study of Tank Fire Control System Based on Value Analysis Method
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作者 窦丽华 张佳 陈杰 《Journal of Beijing Institute of Technology》 EI CAS 2006年第4期411-415,共5页
A method of accuracy assignment based on value analysis method (VAM) in tank fire control system (TFCS) is proposed. From the analysis of primary error sources and their error transfer relationships, the mathemati... A method of accuracy assignment based on value analysis method (VAM) in tank fire control system (TFCS) is proposed. From the analysis of primary error sources and their error transfer relationships, the mathematical model is built on the basis of VAM to solve the accuracy assignment problem. Simulation results show the validation and feasibility of the proposed method. It can help designer of tank fire control system work out an optimal system more efficiently and more economically. 展开更多
关键词 tank fire control system(TFCS) accuracy assignment value analysis method(VAM)
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Diagnostic value of interleukin-8 in colorectal cancer:A case-control study and meta-analysis 被引量:4
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作者 Wen-Jun Jin Jin-Ming Xu +2 位作者 Wen-Li Xu Dong-Hua Gu Pei-Wei Li 《World Journal of Gastroenterology》 SCIE CAS 2014年第43期16334-16342,共9页
AIM:To assess the diagnostic value of serum interleukin-8(IL-8)in the detection of colorectal cancer(CRC).METHODS:An original study was conducted to explore the potential value of IL-8 in CRC diagnosis.Receiver operat... AIM:To assess the diagnostic value of serum interleukin-8(IL-8)in the detection of colorectal cancer(CRC).METHODS:An original study was conducted to explore the potential value of IL-8 in CRC diagnosis.Receiver operating characteristic(ROC)analysis was performed and the area under the curve(AUC)value was calculated.PUBMED and EMBASE were searched(to October,2013),supplemented with manual screening for relevant publications.Meta-analysis methods were applied to pool sensitivity,specificity,positive and negative likelihood ratios,and diagnostic odds ratios and to construct a summary receiver-operating characteristic(s ROC)curve.Heterogeneity across studies was checked by the I2 test and Deek’s funnel plot method was applied to test publication bias.RESULTS:In our original study,serum IL-8 yielded an AUC of 0.742[95%CI:0.635-0.849].The sensitivity and specificity were 85.42%and 54.05%,respectively,at a cut-off value of 5.39.In this meta-analysis,we included five studies with 668 CRC patients and 374controls and one study in our own center with 48 CRC patients and 37 controls.The pooled sensitivity and specificity of IL-8 were 0.69(95%CI:0.42-0.87)and0.85(95%CI:0.68-0.94)for CRC detection.Besides,the area under the s ROC curve was 0.86(95%CI:0.82-0.88).Subgroup analysis suggested that there was no heterogeneity in the Asian subgroup but some in the European subgroup.In addition,no publication bias was found according to the Deek’s funnel plot asymmetry test.CONCLUSION:Serum IL-8 is a promising biomarker for CRC detection and may become a clinically useful tool to identify high-risk patients. 展开更多
关键词 INTERLEUKIN-8 COLORECTAL cancer DIAGNOSTIC value C
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Decentralized robust H-infinity descriptor output feedback control for value-bounded uncertain descriptor large-scale systems 被引量:6
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作者 Yongfang XIE Weihua GUI Zhaohui JIANG 《控制理论与应用(英文版)》 EI 2006年第2期193-200,共8页
For a class of value-bounded uncertain descriptor large-scale interconnected systems, the decentralized robust H∞ descriptor output feedback control problem is investigated. A design method based on the bounded real ... For a class of value-bounded uncertain descriptor large-scale interconnected systems, the decentralized robust H∞ descriptor output feedback control problem is investigated. A design method based on the bounded real lemma is developed for a decentralized descriptor dynamic output feedback controller, which is reduced to a feasibility problem for a nonlinear matrix inequality (NLMI). It is proposed to solve the NLMI iteratively by the idea of homotopy, where some of the variables are fixed alternately at each iteration to reduce the NLMI to a linear matrix inequality (LMI). A given example shows the efficiency of this method . 展开更多
关键词 Descriptor output feedback value-bounded uncertainty Decentralized H-infinity control Homotopy method LMI
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A Control Theoretical Model of Web Service Value Development
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作者 Anthony S. White Doreen Nielsen Michael Censlive 《Open Journal of Modelling and Simulation》 2019年第2期125-147,共23页
This paper describes a control theoretical model of collaborative value development. This model is designed to assist managers in choosing parameters that are critical to the development process in service design and ... This paper describes a control theoretical model of collaborative value development. This model is designed to assist managers in choosing parameters that are critical to the development process in service design and support their Business Model. This methodology uses control system modelling of web-based service value generation implemented in SIMULINK/MATLAB. An application based on public domain Wikipedia data is used to validate and develop the model. A control theoretic model applied to the creation of Wikipedia articles shows very good agreement with Wikipedia published data for the time dependent growth in articles produced, and editors used, well within the variability of parametric data listed publically justifying the principle equations used in the model. This development and fine tuning of the model has been limited by the publically available data. To obtain a more accurate model in this area would need the co-operation of web service organisations to reveal confidential data. This modelling procedure can produce a decision support process for service design and could, with modification be applied much more widely to other choices in service design/implementation, even allowing for user contribution to be evaluated. This work shows how subjective judgements on value and other intangibles need to be continually re-evaluated. Such methodology has not been applied elsewhere to value generation applications. It could be used to rank contributions from co-creators for reward sharing. 展开更多
关键词 Service value control THEORETICAL Model Simulink Simulation WIKIPEDIA DEVELOPMENT
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Consensus Control With a Constant Gain for Discrete-time Binary-valued Multi-agent Systems Based on a Projected Empirical Measure Method 被引量:5
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作者 Ting Wang Min Hu Yanlong Zhao 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2019年第4期1052-1059,共8页
This paper studies the consensus control of multiagent systems with binary-valued observations.An algorithm alternating estimation and control is proposed.Each agent estimates the states of its neighbors based on a pr... This paper studies the consensus control of multiagent systems with binary-valued observations.An algorithm alternating estimation and control is proposed.Each agent estimates the states of its neighbors based on a projected empirical measure method for a holding time.Based on the estimates,each agent designs the consensus control with a constant gain at some skipping time.The states of the system are updated by the designed control,and the estimation and control design will be repeated.For the estimation,the projected empirical measure method is proposed for the binary-valued observations.The algorithm can ensure the uniform boundedness of the estimates and the mean square error of the estimation is proved to be at the order of the reciprocal of the holding time(the same order as that in the case of accurate outputs).For the consensus control,a constant gain is designed instead of the stochastic approximation based gain in the existing literature for binary-valued observations.And,there is no need to make modification for control since the uniform boundedness of the estimates ensures the uniform boundedness of the agents’states.Finally,the systems updated by the designed control are proved to achieve consensus and the consensus speed is faster than that in the existing literature.Simulations are given to demonstrate the theoretical results. 展开更多
关键词 Binary-valued observations CONSENSUS control CONSTANT GAIN convergence rate multi-agent systems projected empirical measure method
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Cost control based on value chain paying equal attention to earning more income and cutting down expense 被引量:1
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作者 HAN Zhi-qing 《Journal of Modern Accounting and Auditing》 2007年第11期14-18,40,共6页
关键词 成本控制 价值链 收益 支出 收入 成本会计
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Using Singular Value to Set Output Disturbance Limits to Feedback ILC Control
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作者 Rashid Alzuabi Athari Alotaibi Humoud Alqattan 《Intelligent Control and Automation》 2022年第2期17-24,共8页
Iterative Learning Control is an effective way of controlling the errors which act directly on the repetitive system. The stability of the system is the main objective in designing. The Small Gain Theorem is used in t... Iterative Learning Control is an effective way of controlling the errors which act directly on the repetitive system. The stability of the system is the main objective in designing. The Small Gain Theorem is used in the design process of State Feedback ILC. The feedback controller along with the Iterative Learning Control adds an advantage in producing a system with minimal error. The past error and current error feedback Iterative control system are studied with reference to the region of disturbance at the output. This paper mainly focuses on comparing the region of disturbance at the output end. The past error feed forward and current error feedback systems are developed on the singular values. Hence, we use the singular values to set an output disturbance limit for the past error and current error feedback ILC system. Thus, we obtain a result of past error feed forward performing better than the current error feedback system. This implies greater region of disturbance suppression to past error feed forward than the other. 展开更多
关键词 Iterative Learning control Disturbance Output Singular values
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An Academic Summary of the International Seminar on “Comparison of the Human Rights value between the East and the West in Epidemic Prevention and Control”
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作者 滕锐 崔萌洁 HU Liang 《The Journal of Human Rights》 2020年第4期515-526,共12页
The international video seminar"Comparison of the Human Rights Values between the East and the West in Epidemic Prevention and Control",hosted by the Institute of Human Rights Law of Huazhong University of S... The international video seminar"Comparison of the Human Rights Values between the East and the West in Epidemic Prevention and Control",hosted by the Institute of Human Rights Law of Huazhong University of Science and Technology,was successfully held on May 30,2020.Against the background of the fight against the CO VID-19 pandemic,this seminar fostered exchanges and discussions on human rights values.As the first country that has contained the epidemic successfully,China shared its experience in the practice of human rights values in epidemic prevention and control,while experts from various countries also shared different human rights values embodied in epidemic prevention and control.This seminar allowed for demonstration of the situation of human rights protection in different countries and regions and exchanges of dilemmas and countermeasures during the specific practice of human rights protection.In the collision of different views and the exchange of multi-dimension dialogues,the seminar called for a sense of a global community of health for all and aimed to foster solidarity and international cooperation for greater contributions to the human rights protection in global epidemic prevention and the development of human rights worldwide. 展开更多
关键词 human rights values epidemic prevention and control the east and the west
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The Study of the Application of the Gray Relevancy Analysis to the Value Chain Based Cost Control 被引量:1
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作者 Xinmin Dai Bin Hao 《Journal of Modern Accounting and Auditing》 2006年第2期22-28,共7页
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The Influence of Spiritual Values on Work Motivation, Management Control, and Quality of Financial Information on IFIs in Indonesia
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作者 Firman Menne Muhammad Ali +1 位作者 Abd. Hamid Habbe Yohanis Rura 《Journal of Modern Accounting and Auditing》 2016年第11期537-555,共19页
关键词 印度尼西亚 信息质量 财务信息 管理控制 精神价值 金融机构 偏最小二乘法 数据分析方法
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VFP中输入类控件和控制类控件value属性的使用
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作者 王亚军 《电脑知识与技术》 2007年第6期1326-1326,1359,共2页
在visual FoxPro 6.0(以下简称VFP)中,输入类和控制类控件value属性的值在程序设计过程中经常会用到,不同控件value属性的值对数据的输入、编辑、查询等控制操作都有重要影响。本文介绍了Visual Foxpro 6.0中输入类和控制类控件va... 在visual FoxPro 6.0(以下简称VFP)中,输入类和控制类控件value属性的值在程序设计过程中经常会用到,不同控件value属性的值对数据的输入、编辑、查询等控制操作都有重要影响。本文介绍了Visual Foxpro 6.0中输入类和控制类控件value属性的各种取值及意义.用实例说明如何通过value属性控制当前记录各字段的取值以及如何解决value属性取值和字段内容不一致等问题,以便使不同字段的内容在VFP程序设计中得到有效控制。 展开更多
关键词 输入类控件 控制类控件 value属性 数据绑定
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Perceived Benefits of Using Value Engineering on Road Projects in Ghana 被引量:2
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作者 James Cofie Danku Philip Agyekum Antwi 《World Journal of Engineering and Technology》 2020年第2期217-236,共20页
The need for Optimum Value benefit realization on Road Projects in developing countries has become topical. While the traditional Cost Control project management process only aligns actual costs with budgeted costs, V... The need for Optimum Value benefit realization on Road Projects in developing countries has become topical. While the traditional Cost Control project management process only aligns actual costs with budgeted costs, Value Engineering (VE) is a sustainable and systematic innovative methodology for establishing the best functional balance among desired features of a project. A Value Engineering (VE) study was conducted with the aim of examining the benefits associated with its use on Road Projects in Ghana. This study employed a two-stage research procedure: desk study and field research. The literature review identified the Optimum Value benefits associated with VE road project management technique as increased Confidence Level in Contract Compliance, reliable Implementation Level of Construction Delivery and enhanced Effectiveness Level of Project Sustainability. A quantitative survey research design based on a purposive sampling technique of selecting respondents was adopted. Employing closed-ended questions, 40 sets of questionnaires were issued to professionals in Road Infrastructure and Support Agencies (RISA) under the Ministry of Roads and Highways (MRH) in the Eastern Region of Ghana. At a response rate of 85%, descriptive statistical analysis (Means, Standard Deviations and Variances) and inferential statistical analysis of variance (ANOVA) test were used to process the data and determine whether there was any significant difference between VE benefit parameters and the groups of respondents. The results revealed that road professionals are familiar with the VE process but solely use Cost Control project management technique. Road professionals recognized the high Optimum Value benefits of professionally ethical Contract Compliance, efficient Construction Delivery and functionally viable Project Sustainability on VE road project management process. 展开更多
关键词 OPTIMUM value COST control value ENGINEERING ROAD PROJECTS Ghana
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Quantifying the Indirect Benefits of Transport Infrastructures and Value Capture Ways in Transportation
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作者 翁东风 仝允桓 费奇 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2001年第4期28-36,共9页
Urban transportation is closely related to land use. The changes of transportation cost and accessibility have a direct impact on land use and land prices. Land exploitation and land use play a role of redistributing ... Urban transportation is closely related to land use. The changes of transportation cost and accessibility have a direct impact on land use and land prices. Land exploitation and land use play a role of redistributing traffic flow in the urban districts. Real property values are regarded as a sole comprehensive index representing all the benefits generated by transport investment. We have applied the theory of time value on transportation to land price model to evaluate the increased value of real estate resulting from improved accessibility. Agency responsible for the development of urban transport infrastructure can capture part of the financial benefit gained by real estate development through a variety of value capture. This enables us to transfer indirect benefit of transport infrastructure construction to transport enterprise and achieve a benign cycle between urban transport investment and land exploitation. 展开更多
关键词 COSTS Highway traffic control INVESTMENTS Motor transportation value engineering
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Steering laws analysis of SGCMGs based on singular value decomposition theory
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作者 张景瑞 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2008年第8期1013-1021,共9页
The steering laws of single gimbal control moment gyros (SGCMGs) are analyzed and compared in this paper for a spacecraft attitude control system based on singular value decomposition (SVD) theory. The mechanism o... The steering laws of single gimbal control moment gyros (SGCMGs) are analyzed and compared in this paper for a spacecraft attitude control system based on singular value decomposition (SVD) theory. The mechanism of steering laws escaping singularity, especially how the steering laws affect singularity of gimbal configuration and the output torque error, is studied using SVD theory. Performance of various steering laws are analyzed and compared quantitatively by simulation. The obtained results can be used as a reference for designers. 展开更多
关键词 single gimbal control moment gyros singular value decomposition steering law SINGULARITY
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A NEW EFFICIENT METHOD TO BOUNDARY VALUE PROBLEM FOR BALLISTIC ROCKET GUIDANCE
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作者 刘新建 袁天保 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2005年第10期1375-1381,共7页
The exploitation of rocket guidance technology on the basis of the guidance law of Space Shuttle and Pegasus rocket was performed. A new efficient method of numerical iteration solution to the boundary value problem w... The exploitation of rocket guidance technology on the basis of the guidance law of Space Shuttle and Pegasus rocket was performed. A new efficient method of numerical iteration solution to the boundary value problem was put forward. The numerical simulation results have shown that the method features good performances of stability, robustness, high precision, and algebraic formulas in real computation. By virtue of modern DSP (digital signal processor ) high speed chip technology, the algorithm can be used in real time and can adaot to the requirements of the big primary bias of rocket guidance. 展开更多
关键词 rocket guidance and control bounoary value problem numerical iteration
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