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A Review of Recent Trends in Quantum Thermodynamics and a System’s Behavioural Analysis of the Universe Originating as a Quantum Energy System
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作者 Stephen J. Palmer 《Journal of Modern Physics》 CAS 2023年第1期60-71,共12页
This paper combines a review of recent advances in quantum thermodynamics, including work on objective collapse (Zurek’s quantum Darwinism) and quantum gravity (Verlinde’s quantum gravity explanation), with a redefi... This paper combines a review of recent advances in quantum thermodynamics, including work on objective collapse (Zurek’s quantum Darwinism) and quantum gravity (Verlinde’s quantum gravity explanation), with a redefinition of entropy generation as systems’ change process. These concepts are used as systems’ behaviour analysis tools to allow us to revisit Hartle and Hawking’s 1983 quantum universe and develop a hypothesis for how physically a universe starting in a quantum state could evolve into our current universe, based on systems analysis. The outcome of this analysis raises a question: do we already have the elements of a “theory of everything” hiding in plain sight within recent advances in quantum thermodynamics? 展开更多
关键词 Exergy Entropy Quantum Thermodynamics Systems Behavioural analysis Quantum Universe
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Contribution of the MERISE-Type Conceptual Data Model to the Construction of Monitoring and Evaluation Indicators of the Effectiveness of Training in Relation to the Needs of the Labor Market in the Republic of Congo
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作者 Roch Corneille Ngoubou Basile Guy Richard Bossoto Régis Babindamana 《Open Journal of Applied Sciences》 2024年第8期2187-2200,共14页
This study proposes the use of the MERISE conceptual data model to create indicators for monitoring and evaluating the effectiveness of vocational training in the Republic of Congo. The importance of MERISE for struct... This study proposes the use of the MERISE conceptual data model to create indicators for monitoring and evaluating the effectiveness of vocational training in the Republic of Congo. The importance of MERISE for structuring and analyzing data is underlined, as it enables the measurement of the adequacy between training and the needs of the labor market. The innovation of the study lies in the adaptation of the MERISE model to the local context, the development of innovative indicators, and the integration of a participatory approach including all relevant stakeholders. Contextual adaptation and local innovation: The study suggests adapting MERISE to the specific context of the Republic of Congo, considering the local particularities of the labor market. Development of innovative indicators and new measurement tools: It proposes creating indicators to assess skills matching and employer satisfaction, which are crucial for evaluating the effectiveness of vocational training. Participatory approach and inclusion of stakeholders: The study emphasizes actively involving training centers, employers, and recruitment agencies in the evaluation process. This participatory approach ensures that the perspectives of all stakeholders are considered, leading to more relevant and practical outcomes. Using the MERISE model allows for: • Rigorous data structuring, organization, and standardization: Clearly defining entities and relationships facilitates data organization and standardization, crucial for effective data analysis. • Facilitation of monitoring, analysis, and relevant indicators: Developing both quantitative and qualitative indicators helps measure the effectiveness of training in relation to the labor market, allowing for a comprehensive evaluation. • Improved communication and common language: By providing a common language for different stakeholders, MERISE enhances communication and collaboration, ensuring that all parties have a shared understanding. The study’s approach and contribution to existing research lie in: • Structured theoretical and practical framework and holistic approach: The study offers a structured framework for data collection and analysis, covering both quantitative and qualitative aspects, thus providing a comprehensive view of the training system. • Reproducible methodology and international comparison: The proposed methodology can be replicated in other contexts, facilitating international comparison and the adoption of best practices. • Extension of knowledge and new perspective: By integrating a participatory approach and developing indicators adapted to local needs, the study extends existing research and offers new perspectives on vocational training evaluation. 展开更多
关键词 MERISE Conceptual Data Model (MCD) Monitoring Indicators Evaluation of Training Effectiveness Training-Employment Adequacy Labor Market Information Systems analysis Adjustment of Training Programs EMPLOYABILITY Professional Skills
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Using structured systems analysis to design an integrated system for transport planning and environmental analysis 被引量:3
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作者 S. P. Losee A. L. Brown (Faculty of Environmental Sciences , Griffith University, Nathan, Queensland, Australia, 4111) 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 1996年第2期129-144,共16页
This paper applies Yourdon's (1989) structured systems analysis techniques to transport planning, and the environmental analysis of transport plans. It is usual for planners to treat these activities as separate p... This paper applies Yourdon's (1989) structured systems analysis techniques to transport planning, and the environmental analysis of transport plans. It is usual for planners to treat these activities as separate processes or 'systems'. Six serious shortcomings are identified in prevailing approaches to accounting for the environmental impacts of transport plans. The application of systems analysis has elucidated opportunities for overcoming these problems by integrating the two processes. The paper highlights the benefits of using these methods to direct research into, and development of, an integrated transport planning- environmental analysis system. Techniques applied are data flow diagrams, a Venn diagram and an entity-relationship diagram. Significant potential exists for integration within a geographic information system(GIS), although adoption of integrated methods by transport planners is likely to be incremental. Research confirms the usefulness of systems analysis in guiding the development of a GIS application to accommodate integrated transport planning and environmental analysis. Systems analysis also facilitates more careful and effective design of the databases underlying GIS analysis. 展开更多
关键词 transport planning travel demand modelling GIS environmental planning systems analysis.
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Experimental and Simulation Analysis of Two-Tone and Three-Tone Photodetector Linearity Characterizing Systems 被引量:1
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作者 费嘉瑞 黄永清 +3 位作者 刘悠欣 刘凯 段晓峰 任晓敏 《Chinese Physics Letters》 SCIE CAS CSCD 2017年第11期110-113,共4页
Two measurement techniques are investigated to characterize photodetector linearity. A model for the two-tone and three-tone photodetector systems is developed to thoroughly investigate the influences of setup compone... Two measurement techniques are investigated to characterize photodetector linearity. A model for the two-tone and three-tone photodetector systems is developed to thoroughly investigate the influences of setup components on the measurement results. We demonstrate that small bias shifts from the quadrature point of the modulator will induce deviation into measurement results of the two-tone system, and the simulation results correspond well to experimental and calculation results. 展开更多
关键词 OIP Experimental and Simulation analysis of Two-Tone and Three-Tone Photodetector Linearity Characterizing Systems IMD dBm
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Dynamic Stability Analysis of Linear Time-varying Systems via an Extended Modal Identification Approach 被引量:2
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作者 Zhisai MA Li LIU +3 位作者 Sida ZHOU Frank NAETS Ward HEYLEN Wim DESMET 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2017年第2期459-471,共13页
The problem of linear time-varying(LTV) system modal analysis is considered based on time-dependent state space representations, as classical modal analysis of linear time-invariant systems and current LTV system mo... The problem of linear time-varying(LTV) system modal analysis is considered based on time-dependent state space representations, as classical modal analysis of linear time-invariant systems and current LTV system modal analysis under the "frozen-time" assumption are not able to determine the dynamic stability of LTV systems. Time-dependent state space representations of LTV systems are first introduced, and the corresponding modal analysis theories are subsequently presented via a stabilitypreserving state transformation. The time-varying modes of LTV systems are extended in terms of uniqueness, and are further interpreted to determine the system's stability. An extended modal identification is proposed to estimate the time-varying modes, consisting of the estimation of the state transition matrix via a subspace-based method and the extraction of the time-varying modes by the QR decomposition. The proposed approach is numerically validated by three numerical cases, and is experimentally validated by a coupled moving-mass simply supported beam exper- imental case. The proposed approach is capable of accurately estimating the time-varying modes, and provides anew way to determine the dynamic stability of LTV systems by using the estimated time-varying modes. 展开更多
关键词 Linear time·varying systems · Extended modal identification · Dynamic stability analysis · Time·varying modes
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Systems Analysis in the Study of the Political Elite
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作者 Nadezhda Ponomarenko 《Chinese Business Review》 2015年第7期354-359,共6页
The main topic of the research is applying of systems approach in studying of political elite. This approach was applied in the analysis of Russia's regional power elite (1991 to 2010). The elite was studied as a c... The main topic of the research is applying of systems approach in studying of political elite. This approach was applied in the analysis of Russia's regional power elite (1991 to 2010). The elite was studied as a complex self-reference system oriented at its own environment, not only in an adaptive way, but first and foremost in structure. The systems approach specifies the following conceptual framework of the study: self-reference, system boundaries, and interaction between the political elite and the surrounding world. Application of the systems analysis to studying the political elite enabled to analyze the structure and functions of the elite, create a model of elitogenesis, and receive study matrix. 展开更多
关键词 political elite system SELF-REFERENCE boundaries of the political elite political elite systems analysis structure of political elite
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The Gene Expression Patterns of Peripheral Blood Mononuclear Cells in Patients with Systemic Lupus Erythematosus
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作者 李守新 江薇 +3 位作者 黄睿 王晓慧 刘文 沈寿引 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2007年第4期367-371,共5页
This study examined the gene expression patterns of peripheral blood mononuclear cells (PBMCs) in patients with systemic lupus erythematosus (SLE) by using serial analysis of gene expression (SAGE) technology. F... This study examined the gene expression patterns of peripheral blood mononuclear cells (PBMCs) in patients with systemic lupus erythematosus (SLE) by using serial analysis of gene expression (SAGE) technology. Following the construction of serial analysis of gene expression (SAGE) library of PBMCs collected from 3 cases of familial SLE patients, a large scale of tag Sequencing was performed. The data extracted from sequencing files was analyzed with SAGE 2000 V 4.5 software. The top 30 expressed genes of SLE patients were uploaded to http://david.niaid.nih.gov/david/ease.htm and the functional classification of genes was obtained. The differences among those expressed gene were analyzed by Chi-square tests. The results showed that a total of 1286 unique SAGE tags were identified from 1814 individual SAGE tags. Among the 1286 unique tags, 86.8% had single copy, and only 0.2% tags had more than 20 copies. And 68.4% of the tags matched known expressed sequences, 41.1% of which matched more than one known expressed sequence. About 31.6% of the tags had no match and could represent potentially novel genes. Approximately one third of the top 30 genes were ribosomal protein, and the rest were genes related to metabolism or with unknown functions. Eight tags were found to express differentially in SAGE library of SLE patients. This study draws a profile of gene expression patterns of PBMCs in patients with SLE. Comparison of SAGE database from PBMCs between normal individuals and SLE patients will help us to better understand the pathogenesis of SLE. 展开更多
关键词 systemic lupus erythematosus of serial analysis gene expression peripheral blood mononuclear cells
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滚-跳多运动模式球形机器人的动力学仿真研究 被引量:1
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作者 于源 吴怀松 +1 位作者 焦志伟 李秉洋 《北京化工大学学报(自然科学版)》 CAS CSCD 北大核心 2023年第1期89-96,共8页
复杂的探索环境对探测机器人的通行能力提出了更高要求,具有多种运动模式的球形机器人是探测机器人领域的研究热点之一。通过对球形机器人内部构件质量分布的调节,设计了一种基于单摆驱动式的滚-跳多运动模式球形机器人,其具有滚动、转... 复杂的探索环境对探测机器人的通行能力提出了更高要求,具有多种运动模式的球形机器人是探测机器人领域的研究热点之一。通过对球形机器人内部构件质量分布的调节,设计了一种基于单摆驱动式的滚-跳多运动模式球形机器人,其具有滚动、转向、爬坡与跳跃4种基本运动能力;随后,又根据球形机器人的设计方案建立了球形机器人4种基本运动动力学方程。利用Automatic Dynamics Analysis of Mechanical Systems(ADAMS)软件构建该球形机器人虚拟样机并对其进行了滚动、转向、爬坡与跳跃的动力学仿真,最后以此为依据计算滚动、转向、爬坡与跳跃运动性能的仿真值,并制作实验室样机验证了动力学仿真的正确性。 展开更多
关键词 球形机器人 多运动模式 动力学仿真 Automatic Dynamics analysis of Mechanical Systems(ADAMS)
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Reliability Analysis of Unmanned Aerial Vehicles Flight Control System Based on Reliability Analysis Technologies
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作者 CAI Shuang JIANG Guangjun 《Journal of Donghua University(English Edition)》 EI CAS 2018年第3期264-269,共6页
The unmanned aerial vehicles( UAV) has been becoming more and more important in the aviation industry.Despite the superior performance and advanced technology,major accident of UAV happens frequently due to the impact... The unmanned aerial vehicles( UAV) has been becoming more and more important in the aviation industry.Despite the superior performance and advanced technology,major accident of UAV happens frequently due to the impact of their systems,long distance of remote control and skill of manipulator technology.According to the application of engineering application,failure mode effects and criticality analysis( FMECA),failure reporting analysis and corrective action comprehensive analysis systems( FRACAS)and fault tree analysis( FTA)( 3 F) were combined.And also a set of user-friendly,more time,more efficient and accurate reliability analysis system were explored. 展开更多
关键词 failure mode effect and criticality analysis(FMECA) failure reporting analysis and corrective action comprehensive analysis systems(FRACAS) fault tree analysis(FTA) 3F integrated system analysis
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An Analysis of Mutual Interference in Radar Systems Using Dual-Band (Ka / X) Antennas
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作者 DU Shimin, Beijing Institute of Radio Measurement, P.O.Box 3923-2, Beijing 100854, China WANG Baofa, Beijing University of Aeronautics and Astronautics, Beijing, China WU Yi, No.2 Radio Instrument Factory of Beijing, Beijing, China 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 1992年第4期84-87,共4页
An analysis of mutual interfering sources on RF systems using dual-band (Ka / X) radar is presented. The purpose of this paper is to improve operational performance of the system from the point of view of EMC design. ... An analysis of mutual interfering sources on RF systems using dual-band (Ka / X) radar is presented. The purpose of this paper is to improve operational performance of the system from the point of view of EMC design. The experimental dual-band antenna system have decreased the disturbing effects of most mutual interfering sources. 展开更多
关键词 ANTENNAS KA An analysis of Mutual Interference in Radar Systems Using Dual-Band
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Workshop on Simulation and Systems Analysis for Rice Production(SARP) held at CNRRI
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作者 ZHU Defeng,CNRRI 《Chinese Rice Research Newsletter》 1995年第4期12-12,共1页
SARP Workshop on risk analysis of agroecological zonation and optimization of crop rotation was held at CNRRI’s research center on 24—27 Oct, 1995. Experts from Philippines, India, China, and IRRI were present in th... SARP Workshop on risk analysis of agroecological zonation and optimization of crop rotation was held at CNRRI’s research center on 24—27 Oct, 1995. Experts from Philippines, India, China, and IRRI were present in the workshop. Participants exchanged the research results on the field of land use, soil erosion. optimization of rice—wheat, rice—peanut, rice—corn cropping system in the different environments, risk analysis of rice based cropping system, nitrogen balance in rice based cropping system with system approach, demonstrated models used in their studies, and discussed the ongoing cooperative research. 展开更多
关键词 SIMULATION held at CNRRI Workshop on Simulation and Systems analysis for Rice Production SARP
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Multi-Actor Geo-Collaborative Device for Collecting Household Waste in Urban Areas: A Case Study of Lamkansa District, Casablanca, Morocco 被引量:1
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作者 Abdessalam Hijab Eric Henry Hafida Boulekbache 《Intelligent Information Management》 2021年第6期269-285,共17页
The aim of this paper is to develop a Multi-Actor Geo-Collaborative Device to improve the processes of household waste collect (HWC) in urban areas. The proposed device will be tested in the Lamkansa district, in the ... The aim of this paper is to develop a Multi-Actor Geo-Collaborative Device to improve the processes of household waste collect (HWC) in urban areas. The proposed device will be tested in the Lamkansa district, in the southwestern part of Casablanca city, Morocco. The approach used is a systemic analysis of communication in order to act on a territory. We have been inspired by several methodological developments concerning multi-actor processes of land use planning. We focused our work on the involvement of the inhabitants in the process of household waste collect. The results show that the urban population can help and contribute to the development of complementary solutions to improve the urban environment and their living environment. Moreover, by integrating citizens in HWC processes, as well as decision communication, we can reduce household waste management costs and make it faster and more efficient, through a geo-collaborative, participatory and incentive logic. The approach described in this article is original, not only considering the technologies used to present and share the collected information, but also regarding the concept of integrating several actors in a collaborative/incentive mode. It arouses great interest by combining geomatics with communication and information sciences. It contributes to improve the participation of the inhabitants in the life of their urban environment in order to establish a reinforced dialogue on the future of their city and public health. Also, it involves the development and testing of new devices and tools for multi-actor collaboration. 展开更多
关键词 ICT GIS systemic analysis Communication and Collaboration Processes Population Participation Household Waste and Urban Environment Lamkansa
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Establishment of the Basic Theory of Fuze Safety Systems
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作者 范宁军 马宝华 《Journal of Beijing Institute of Technology》 EI CAS 1993年第2期153-160,共8页
Presents a series of new concepts and design ideas about the fuze safety system, establishing thereby a proposed theory and relevant mathematical descriptions. The basic the- ory indicates that any fuze safety system ... Presents a series of new concepts and design ideas about the fuze safety system, establishing thereby a proposed theory and relevant mathematical descriptions. The basic the- ory indicates that any fuze safety system is a physical system comprising finite safety ele- ments each of which can independently affect the system's states, and the arming process is a dynamic one in which the extent of safety of the system changes only gradually. The theory and method can be used to analyse the arming process and to guide the development of fuze safety systems. 展开更多
关键词 FUZE fuze safety systems analysis / safety and arrming system
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Integrated watershed management:evolution,development and emerging trends 被引量:4
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作者 Guangyu Wang Shari Mang +4 位作者 Haisheng Cai Shirong Liu Zhiqiang Zhang Liguo Wang John L.Innes 《Journal of Forestry Research》 SCIE CAS CSCD 2016年第5期967-994,共28页
Watershed management is an ever-evolving practice involving the management of land, water, biota, and other resources in a defined area for ecological, social, and economic purposes. In this paper, we explore the foll... Watershed management is an ever-evolving practice involving the management of land, water, biota, and other resources in a defined area for ecological, social, and economic purposes. In this paper, we explore the following questions: How has watershed management evolved? What new tools are available and how can they be integrated into sustainable watershed management? To address these questions, we discuss the process of developing integrated watershed management strategies for sustainable manage- ment through the incorporation of adaptive management techniques and traditional ecological knowledge. We address the numerous benefits from integration acrossdisciplines and jurisdictional boundaries, as well as the incorporation of technological advancements, such as remote sensing, GIS, big data, and multi-level social-eco- logical systems analysis, into watershed management strategies. We use three case studies from China, Europe, and Canada to review the success and failure of integrated watershed management in addressing different ecological, social, and economic dilemmas in geographically diverse locations. Although progress has been made in watershed management strategies, there are still numerous issues impeding successful management outcomes; many of which can be remedied through holistic management approaches, incorporation of cutting-edge science and technology, and cross-jurisdictional coordination. We conclude by high- lighting that future watershed management will need to account for climate change impacts by employing techno- logical advancements and holistic, cross-disciplinary approaches to ensure watersheds continue to serve their ecological, social, and economic functions. We present three case studies in this paper as a valuable resource for scientists, resource managers, government agencies, and other stakeholders aiming to improve integrated watershed management strategies and more efficiently and successfully achieve ecological and socio-economic management objectives. 展开更多
关键词 Adaptive management Climate change impacts Social-ecological systems analysis Traditional ecological knowledge Watershed management
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A Cognitive Memory-Augmented Network for Visual Anomaly Detection 被引量:6
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作者 Tian Wang Xing Xu +1 位作者 Fumin Shen Yang Yang 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2021年第7期1296-1307,共12页
With the rapid development of automated visual analysis,visual analysis systems have become a popular research topic in the field of computer vision and automated analysis.Visual analysis systems can assist humans to ... With the rapid development of automated visual analysis,visual analysis systems have become a popular research topic in the field of computer vision and automated analysis.Visual analysis systems can assist humans to detect anomalous events(e.g.,fighting,walking alone on the grass,etc).In general,the existing methods for visual anomaly detection are usually based on an autoencoder architecture,i.e.,reconstructing the current frame or predicting the future frame.Then,the reconstruction error is adopted as the evaluation metric to identify whether an input is abnormal or not.The flaws of the existing methods are that abnormal samples can also be reconstructed well.In this paper,inspired by the human memory ability,we propose a novel deep neural network(DNN)based model termed cognitive memory-augmented network(CMAN)for the visual anomaly detection problem.The proposed CMAN model assumes that the visual analysis system imitates humans to remember normal samples and then distinguishes abnormal events from the collected videos.Specifically,in the proposed CMAN model,we introduce a memory module that is able to simulate the memory capacity of humans and a density estimation network that can learn the data distribution.The reconstruction errors and the novelty scores are used to distinguish abnormal events from videos.In addition,we develop a two-step scheme to train the proposed model so that the proposed memory module and the density estimation network can cooperate to improve performance.Comprehensive experiments evaluated on various popular benchmarks show the superiority and effectiveness of the proposed CMAN model for visual anomaly detection comparing with the state-of-the-arts methods.The implementation code of our CMAN method can be accessed at https://github.com/CMANcode/CMAN_pytorch. 展开更多
关键词 Cognitive computing density estimation MEMORY visual analysis systems visual anomaly detection.
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Modelling User Needs:Students as Enterprise Analysts 被引量:1
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作者 GIANMARIO Motta THIAGO Barroero Daniele Sacco 《计算机教育》 2012年第10期64-68,共5页
We illustrate a case study,where students designed enterprise architectures,that were not only welcome but successfully implemented.The success key was threefold.First the analysis framework,that integrates all the as... We illustrate a case study,where students designed enterprise architectures,that were not only welcome but successfully implemented.The success key was threefold.First the analysis framework,that integrates all the aspects of the systems that are relevant to users,namely user interface,rules,and information.Second,the analysis approach,that guides,trough confirmatory sessions,to elicit real requirements from users.Third,the model-to-model transformation,that assures consistency from the highest aggregate abstraction down to an executable model. 展开更多
关键词 Enterprise Architecture User Requirements Requirements Collection analysis Systems analysis Software Engineering Education Business Process analysis User Needs
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DESIGN OF RECONFIGURABLE MANUFACTURING SYSTEMS WITH STRONGLY COUPLED NATURE 被引量:1
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作者 LANG Sherman Y T 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2007年第1期91-95,共5页
Today's manufacturing cnvironmem forces manufacturing companies to make as many product variations as possible at affordable costs within a short time. Mass customisation is one of most important technologies for com... Today's manufacturing cnvironmem forces manufacturing companies to make as many product variations as possible at affordable costs within a short time. Mass customisation is one of most important technologies for companies to achieve their objectives. Efforts to mass customisation should be made on two aspects: (1) To modularize products and make them as less differences as possible; (2) To design manufacturing resources and make them provide as many processes variations as possible. This paper reports our recent work on aspect (2), i.e. how to design a reconfignrable manufacturing system (RMS) so that it can be competent to accomplish various processes optimally; Reconfignrable robot system (RRS) is taken as an example. RMS design involves architecture design and configuration design, and configuration design is further divided in design analysis and design synthesis. Axiomatic design theory (ADT) is applied to architecture design, the features and issues of RRS configuration design are discussed, automatic modelling method is developed for design analysis, and concurrent design methodology is presented for design synthesis. 展开更多
关键词 Mass customisation Reconfignrable manufacturing systems Reconfignrable robotic system analysis Synthesis Architecture Adaptability Reconfignrability Configuration design
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Combination of terrestrial reference frames based on space geodetic techniques in SHAO:methodology and main issues 被引量:2
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作者 Bing He Xiao-Ya Wang +1 位作者 Xiao-Gong Hu Qun-He Zhao 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2017年第9期1-14,共14页
Based on years of input from the four geodetic techniques (SLR, GPS, VLBI and DORIS), the strategies of the combination were studied in SHAO to generate a new global terrestrial reference frame as the material reali... Based on years of input from the four geodetic techniques (SLR, GPS, VLBI and DORIS), the strategies of the combination were studied in SHAO to generate a new global terrestrial reference frame as the material realization of the ITRS defined in IERS Conventions. The main input includes the time series of weekly solutions (or fortnightly for SLR 1983-1993) of observational data for satellite techniques and session-wise normal equations for VLBI. The set of estimated unknowns includes 3- dimensional Cartesian coordinates at the reference epoch 2005.0 of the stations distributed globally and their rates as well as the time series of consistent Earth Orientation Parameters (EOPs) at the same epochs as the input. Besides the final solution, namely SOL-2, generated by using all the inputs before 2015.0 obtained from short-term observation processing, another reference solution, namely SOL- 1, was also computed by using the input before 2009.0 based on the same combination of procedures for the purpose of comparison with ITRF2008 and DTRF2008 and for evaluating the effect of the latest six more years of data on the combined results. The estimated accuracy of the x-component and y-component of the SOL- 1 TRF-origin was better than 0.1 mm at epoch 2005.0 and better than 0.3 mm yr- 1 in time evolution, either compared with ITRF2008 or DTRF2008. However, the z-component of the translation parameters from SOL-1 to ITRF2008 and DTRF2008 were 3.4 mm and -1.0 ram, respectively. It seems that the z-component of the SOL-1 TRF-origin was much closer to the one in DTRF2008 than the one in ITRF2008. The translation parameters from SOL-2 to ITRF2014 were 2.2, -1.8 and 0.9 mm in the x-, y- and z-components respectively with rates smaller than 0.4 mmyr-1. Similarly, the scale factor transformed from SOL-1 to DTRF2008 was much smaller than that to ITRF2008. The scale parameter from SOL-2 to ITRF2014 was -0.31 ppb with a rate lower than 0.01 ppb yr-1. The external precision (WRMS) compared with IERS EOP 08 C04 of the combined EOP series was smaller than 0.06 mas for the polar motions, smaller than 0.01 ms for the UT1-UTC and smaller than 0.02 ms for the LODs. The precision of the EOPs in SOL-2 was slightly higher than that of SOL-1. 展开更多
关键词 astrometry w reference systems -- techniques: interferometers -- methods: data analysis
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DECENTRALIZED ROBUST CONTROL FOR UNCERTAIN FLEXIBLE SPACE STATION
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作者 Wang Qing Chen Xinhai(College of Astronautics, Northtvestern Pclytechnical University, Xi’an, China, 710072) 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 1996年第3期162-168,共7页
A decentralized variable-structure robust control technique for uncertain large-scale systems is proposed and using the proposed technique. a decentralized robust control system for uncertain flexible space station is... A decentralized variable-structure robust control technique for uncertain large-scale systems is proposed and using the proposed technique. a decentralized robust control system for uncertain flexible space station is designed. The designed robust control system can guarantee the stability and safe operation of space station in a wide range of system parameters variations and highly intensive external disturbances. In addition. because decentralized adaptation laws for the upper bounds of system uncertainties are introduced, the control technique is particularly applicable to the uncertain flexible space station with complex structure whose bounds of system uncertainties can not be determined or vary with time. 展开更多
关键词 flexible space structures ROBUSTNESS control systems design systems analysis adaptive control
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System Simulation Science and Simulation System Technology
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作者 Chuanyuan, Wen 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 1993年第4期2-11,共10页
This paper mainly discusses the following problems: the important meaning and special function of simulation system; the definition, contents and relationship of system and system simulation science; the definition an... This paper mainly discusses the following problems: the important meaning and special function of simulation system; the definition, contents and relationship of system and system simulation science; the definition and technology of simulation system and its equipments; and systematic description and exploration in relation to the developing trend of system simulation science and simulation system technology. 展开更多
关键词 Analog computers Control systems Digital computers Flight simulators Mathematical models Systems analysis Systems engineering Systems science Technology
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