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An Intelligent Quality Control Method for Manufacturing Processes Based on a Human–Cyber–Physical Knowledge Graph
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作者 Shilong Wang Jinhan Yang +2 位作者 Bo Yang Dong Li Ling Kang 《Engineering》 SCIE EI CAS CSCD 2024年第10期242-260,共19页
Quality management is a constant and significant concern in enterprises.Effective determination of correct solutions for comprehensive problems helps avoid increased backtesting costs.This study proposes an intelligen... Quality management is a constant and significant concern in enterprises.Effective determination of correct solutions for comprehensive problems helps avoid increased backtesting costs.This study proposes an intelligent quality control method for manufacturing processes based on a human–cyber–physical(HCP)knowledge graph,which is a systematic method that encompasses the following elements:data management and classification based on HCP ternary data,HCP ontology construction,knowledge extraction for constructing an HCP knowledge graph,and comprehensive application of quality control based on HCP knowledge.The proposed method implements case retrieval,automatic analysis,and assisted decision making based on an HCP knowledge graph,enabling quality monitoring,inspection,diagnosis,and maintenance strategies for quality control.In practical applications,the proposed modular and hierarchical HCP ontology exhibits significant superiority in terms of shareability and reusability of the acquired knowledge.Moreover,the HCP knowledge graph deeply integrates the provided HCP data and effectively supports comprehensive decision making.The proposed method was implemented in cases involving an automotive production line and a gear manufacturing process,and the effectiveness of the method was verified by the application system deployed.Furthermore,the proposed method can be extended to other manufacturing process quality control tasks. 展开更多
关键词 Quality control Human-cyber-physical ternary data knowledge graph
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The Impact of Optimizing Details in the Operating Room on the Level of Knowledge, Attitude, and Practice of Hospital Infection Prevention and Control by Surgeons, as Well as the Effectiveness of Infection Control
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作者 Yuanyuan Zhang 《Surgical Science》 2024年第7期421-429,共9页
Objective: This paper aims to explore the impact of optimizing details in the operating room on the level of knowledge, attitude, and practice of hospital infection prevention and control by surgeons, as well as the e... Objective: This paper aims to explore the impact of optimizing details in the operating room on the level of knowledge, attitude, and practice of hospital infection prevention and control by surgeons, as well as the effectiveness of infection control. Methods: From January 2022 to June 2023, a total of 120 patients were screened and randomly divided into a control group (routine care and hospital infection management) and a study group (optimizing details in the operating room). Results: Significant differences were found between the two groups in the data of surgeons’ level of knowledge, attitude, and practice in hospital infection prevention and control, infection rates, and nursing satisfaction, with the study group showing better results (P Conclusion: The use of optimizing details in the operating room among surgeons can effectively improve surgeons’ level of knowledge, attitude, and practice in hospital infection prevention and control, reduce infection occurrence, and is worth promoting. 展开更多
关键词 Optimizing Details in the Operating Room Infection Level of knowledge ATTITUDE and Practice Infection control
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Knowledge and awareness of infection control practices among nursing professionals:A cross-sectional survey from South Asia and the Middle East
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作者 Kanwalpreet Sodhi Gunjan Chanchalani +17 位作者 Muktanjali Arya Gentle S Shrestha Juhi N Chandwani Manender Kumar Monika G Kansal Mohammad Ashrafuzzaman Anushka D Mudalige Ashraf Al Tayar Bassam Mansour Hasan M Saeed Madiha Hashmi Mitul Das Nehad N Al Shirawi Ranjan Mathias Wagih O Ahmed Amandeep Sharma Diptimala Agarwal Prashant Nasa 《World Journal of Critical Care Medicine》 2023年第3期176-187,共12页
BACKGROUND The proficiency of nursing professionals in the infection prevention and control(IPC)practices is a core component of the strategy to mitigate the challenge of healthcare associated infections.AIM To test k... BACKGROUND The proficiency of nursing professionals in the infection prevention and control(IPC)practices is a core component of the strategy to mitigate the challenge of healthcare associated infections.AIM To test knowledge of nurses working in intensive care units(ICU)in South Asia and Middle East countries on IPC practices.METHODS An online self-assessment questionnaire based on various aspects of IPC practices was conducted among nurses over three weeks.RESULTS A total of 1333 nurses from 13 countries completed the survey.The average score was 72.8%and 36%of nurses were proficient(mean score>80%).43%and 68.3%of respondents were from government and teaching hospitals,respectively.79.2%of respondents worked in<25 bedded ICUs and 46.5%in closed ICUs.Statistically,a significant association was found between the knowledge and expertise of nurses,the country’s per-capita income,type of hospitals,accreditation and teaching status of hospitals and type of ICUs.Working in high-and upper-middleincome countries(β=4.89,95%CI:3.55 to 6.22)was positively associated,and the teaching status of the hospital(β=-4.58,95%CI:-6.81 to-2.36)was negatively associated with the knowledge score among respondents.CONCLUSION There is considerable variation in knowledge among nurses working in ICU.Factors like income status of countries,public vs private and teaching status of hospitals and experience are independently associated with nurses’knowledge of IPC practices. 展开更多
关键词 knowledge ATTITUDE Policy compliance Infection control Infection control practices Nurses
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Quantum Algorithm of Imperfect KB Self-organization. Pt II: Robotic Control with Remote Knowledge Base Exchange
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作者 A.G.Reshetnikov S.V.Ulyanov 《Artificial Intelligence Advances》 2021年第2期44-70,共27页
The technology of knowledge base remote design of the smart fuzzy con­trollers with the application of the"Soft/quantum computing optimizer"toolkit software developed.The possibility of the transmission... The technology of knowledge base remote design of the smart fuzzy con­trollers with the application of the"Soft/quantum computing optimizer"toolkit software developed.The possibility of the transmission and commu­nication the knowledge base using remote connection to the control object considered.Transmission and communication of the fuzzy controller’s knowledge bases implemented through the remote connection with the control object in the online mode apply the Bluetooth or WiFi technologies.Remote transmission of knowledge bases allows designing many different built-in intelligent controllers to implement a variety of control strategies under conditions of uncertainty and risk.As examples,two different models of robots described(mobile manipulator and(“cart-pole”system)inverted pendulum).A comparison of the control quality between fuzzy controllers and quantum fuzzy controller in various control modes is presented.The ability to connect and work with a physical model of control object without using than mathematical model demonstrated.The implemented technol­ogy of knowledge base design sharing in a swarm of intelligent robots with quantum controllers.It allows to achieve the goal of control and to gain additional knowledge by creating a new quantum hidden information source based on the synergetic effect of combining knowledge.Develop­ment and implementation of intelligent robust controller’s prototype for the intelligent quantum control system of mega-science project NICA(at the first stage for the cooling system of superconducted magnets)is discussed.The results of the experiments demonstrate the possibility of the ensured achievement of the control goal of a group of robots using soft/quantum computing technologies in the design of knowledge bases of smart fuzzy controllers in quantum intelligent control systems.The developed software toolkit allows to design and setup complex ill-defined and weakly formal­ized technical systems on line. 展开更多
关键词 Quantum software engineering Quantum algorithm Group of intelligent robots Multi-agent system Intelligent control Fuzzy controller Remote transmission of knowledge knowledge synergetic
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Criteria Selecting Knowledge Base in the FuzzyController of the Electrohydraulic Position Control System
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作者 高建臣 吴平东 《Journal of Beijing Institute of Technology》 EI CAS 1998年第1期84-91,共8页
Aim To analyse the influence of knowledge base on the performance of the fuzzy controller of the electrohydraulic position control system,and to determine their selection cri- teria. Methods Experiments based on diffe... Aim To analyse the influence of knowledge base on the performance of the fuzzy controller of the electrohydraulic position control system,and to determine their selection cri- teria. Methods Experiments based on different membership functions,scaling factors and con-trol rules were done separately.The experiment results and the influence of different know- ledge base on the control performance were analysed in theory so that criteria of selcting knowledge base can be summarized correctly.Results Knowledge base,including membershipfunctions, scaling factors and control rules,has a crucial effect on the fuzzy control system.Suitably selected knowledge base can lead to good control performance of fuzzy control sys-tem. Conclusion Being symmetric,having an intersection ratio of 1 and satisfying width con- dition are three necessities for selecting membership functions.Selecting scaling factors dependson both the system requirement and a comprehensive analysis in the overshoot,oscillation, rising time and stability. Integrity and continuity must be guaranteed when determining control rules. 展开更多
关键词 fuzzy control knowledge base position control systems fuzzy sets
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The DAO to MetaControl for MetaSystems in Metaverses:The System of Parallel Control Systems for Knowledge Automation and Control Intelligence in CPSS 被引量:24
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作者 Fei-Yue Wang 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2022年第11期1899-1908,共10页
An investigation and outline of MetaControl and DeControl in Metaverses for control intelligence and knowledge automation are presented.Prescriptive control with prescriptive knowledge and parallel philosophy is propo... An investigation and outline of MetaControl and DeControl in Metaverses for control intelligence and knowledge automation are presented.Prescriptive control with prescriptive knowledge and parallel philosophy is proposed as the starting point for the new control philosophy and technology,especially for computational control of metasystems in cyberphysical-social systems.We argue that circular causality,the generalized feedback mechanism for complex and purposive systems,should be adapted as the fundamental principle for control and management of metasystems with metacomplexity in metaverses.Particularly,an interdisciplinary approach is suggested for MetaControl and DeControl as a new form of intelligent control based on five control metaverses:MetaVerses,MultiVerses,InterVerses,TransVerse,and DeepVerses. 展开更多
关键词 Metacontrol MetaSystems Metaverses CPSS DAO Decontrol Prescriptive control Parallel control Computational control knowledge Automation control Intelligence Parallel Intelligence
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S-rough sets and knowledge separation 被引量:104
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作者 Shi Kaiquan 1,21. School of Mathematics and System Sciences, Liaocheng University, Liaocheng 252059, P. R. China 2. School of Mathematics and System Sciences, Shandong University, Jinan 250100, P. R. China 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2005年第2期403-410,共8页
The conceptions of the knowledge screen generated by S-rough sets are given: f- screen and - screen , and then puts forward - filter theorem, - filter theorem of knowledge. At last, the applications of knowledge separ... The conceptions of the knowledge screen generated by S-rough sets are given: f- screen and - screen , and then puts forward - filter theorem, - filter theorem of knowledge. At last, the applications of knowledge separation are given according to - screen and - screen. 展开更多
关键词 S- rough sets f- screen - screen f-filter theorem - filter theorem knowledge separation.
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Knowledge Graph Based Method for Tracing Quality of Aerospace Products
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作者 WANG Ning CAO Lijun +5 位作者 DING Siyi MENG Yan LIU Huan ZHENG Xiaohu HUANG Wenbin LIU Xiaojia 《Journal of Donghua University(English Edition)》 CAS 2024年第5期513-524,共12页
Nowadays,the internal structure of spacecraft has been increasingly complex.As its“lifeline”,cables require extensive manpower and resources for manual testing,and it is challenging to quickly and accurately locate ... Nowadays,the internal structure of spacecraft has been increasingly complex.As its“lifeline”,cables require extensive manpower and resources for manual testing,and it is challenging to quickly and accurately locate quality problems and find solutions.To address this problem,a knowledge graph based method is employed to extract multi-source heterogeneous cable knowledge entities.The method utilizes the bidirectional encoder representations from transformers(BERT)network to embed word vectors into the input text,then extracts the contextual features of the input sequence through the bidirectional long short-term memory(BiLSTM)network,and finally inputs them into the conditional random field(CRF)network to predict entity categories.Simultaneously,by using the entities extracted by this model as the data layer,a knowledge graph based method has been constructed.Compared to other traditional extraction methods,the entity extraction method used in this study demonstrates significant improvements in metrics such as precision,recall and an F1 score.Ultimately,employing cable test data from a particular aerospace precision machining company,the study has constructed the knowledge graph based method in the field to achieve visualized queries and the traceability and localization of quality problems. 展开更多
关键词 knowledge graph named entity recognition quality control aerospace product
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f-heredity knowledge and f-heredity mining 被引量:14
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作者 Cui Minghui Shi Kaiquan 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2006年第4期798-801,810,共5页
Using S-rough sets, this paper gives the concepts off-heredity knowledge and its heredity coefficient, and f-variation coefficient of knowledge; presents the theorem of f-attribute dependence of variation coefficient ... Using S-rough sets, this paper gives the concepts off-heredity knowledge and its heredity coefficient, and f-variation coefficient of knowledge; presents the theorem of f-attribute dependence of variation coefficient and the relation theorem of heredity-variation. The attribute dependence of f-variation coefficient and the relation of heredity-variation are important characteristics of S-rough sets. From such discussion, this paper puts forward the heredity mining off-knowledge and the algorithm of heredity mining, also gives its relative application. 展开更多
关键词 S-rough sets f-heredity knowledge f-variation coefficient the theorem of f-attribute dependence of variation coefficient the relation theorem of heredity - variation algorithm off-heredity mining application.
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Indigenous Knowledge of Natural Resource Management and Population Control for Dong Ethnic Group in Guizhou Province
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作者 Yuan Juanwen1,2, Wu Quanxing3 1. School of Resources and Environmental Management, Guizhou College of Finance and Economics, Guiyang Guizhou 550004, China 2. Sociology of Consumers and Households, Wageningen University and Research, Wageningen, 6700 KN, The Netherlands 3. Cultural Institute, Qiandongnan Miao and Dong Autonomous Prefecture, Kaili Guizhou 556000, China 《Chinese Journal of Population,Resources and Environment》 2010年第3期11-16,共6页
Dong ethnic people have rich indigenous knowledge in terms of their daily life and production, which plays an important role in the sustainable development of their village. This paper aims to understand traditional k... Dong ethnic people have rich indigenous knowledge in terms of their daily life and production, which plays an important role in the sustainable development of their village. This paper aims to understand traditional knowledge of Dong ethnic people in resource management and population control, including traditional resource management, traditional medicinal knowledge and village regulations in Zhanli Village in Southeast Guizhou Province. The research methods include key informant interview, group discussion, participant observation and secondary data collect- ing. The results show that Zhanli villagers try their best to utilize indigenous knowledge to manage the natural resources and keep the stable population to make themselves live in a sustainable way. Indigenous knowledge plays an important role in managing their limited natural resources and keeping the population stable under an excellent condition. Zhanli villagers employ indigenous knowledge to manage natural resources and use local herbs to control the population. Village regulation terms significantly influence villagers’ awareness in resource management and birth control. Women play the chief role in employing indigenous knowledge in weaving as well as medicinal knowledge in birth control, and these kinds of knowledge are passed down through the female line. However, the inheritance style of traditional knowledge is decreasing. Indig- enous knowledge plays an important role in the sustainable development of this village, which gives implications for development practices to involve indigenous knowledge to achieve sustainable development. 展开更多
关键词 traditional knowledge natural resource management population control Dong ethnicity GUIZHOU
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Hygienic and Dietary Measures in Cameroonian Hypertensive Patients Followed at the Douala General Hospital: Knowledge, Compliance and Effect on Blood Pressure Control
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作者 Félicité Kamdem Grace Eugénie Makota Ndongo +11 位作者 Christelle Noche Domngang Hamadou Ba Jaff Fenkeu Kweban Glwadys Ngono Atéba Sidick Mouliom Henri Ngoté Lade Viché Caroline Kenmegne Marie Solange Ndom Ebongue Siddikatou Djibrilla Elysée Claude Bika Léle Samuel Kingue 《World Journal of Cardiovascular Diseases》 CAS 2023年第1期21-31,共11页
Introduction: The management of hypertension is mostly based on pharmacotherapy and hygienic and dietary measures (HDMs) for which little data is available in Cameroon. The concern to improve the quality of life of hy... Introduction: The management of hypertension is mostly based on pharmacotherapy and hygienic and dietary measures (HDMs) for which little data is available in Cameroon. The concern to improve the quality of life of hypertensive patients led us to study the knowledge, compliance and effect of HDMs among Cameroonian hypertensive patients. Methods: This was a cross-sectional study carried out at the Douala General Hospital;the census of patients was carried out from 05 March to 10 May 2018. The data evaluated were knowledge and compliance with HDMs with an inference of their effect on blood pressure control. Results: We recruited 330 participants at mean age of 60 ± 11 years, 37.9% men;57.3% with blood pressure (BP) controlled. Out of 330 subjects, 308 (93.3%) who had been educated about dietary health measures for hypertension were assessed on knowledge, compliance and effect of these measures against 22 (6.7%) who had never heard about them. Around 85.7% of participants had good knowledge of HDMs and 78.9% had good compliance with them. There was no statistically significant influence of knowledge and compliance with HDMs on blood pressure control. Conclusion: The level of knowledge and adherence to HDMs of hypertensive patients at the Douala General Hospital was appreciable. It is however appropriate for physicians to intensify patient education on HDMs and BP control. 展开更多
关键词 HYPERTENSION Hygienic and Dietary Measures Blood Pressure control knowledge COMPLIANCE
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Control and its role in the process of ensuring knowledge continuity
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作者 Hana Urbancova Martina Konigova 《Journal of Modern Accounting and Auditing》 2010年第7期38-45,57,共9页
With the commencement of the 21st century, the information age, knowledge economy and integration of information and knowledge among production factors, organizations show increasing interest in knowledge management. ... With the commencement of the 21st century, the information age, knowledge economy and integration of information and knowledge among production factors, organizations show increasing interest in knowledge management. Managers are trying not only to preserve knowledge and transfer it efficiently within their organization, but also to ensure that it is not lost when a knowledge employee leaves the organization. Therefore, it is indispensable for organizations to monitor, record, transfer and preserve their knowledge. In order to ensure efficient preservation of knowledge by the organization, it is essential to integrate the area of the so-called knowledge continuity into the general management and ensure its maximum value. The goal of the article is to identify the role of control in the transformation process and its impact on ensuring knowledge continuity within the organization. A partial goal lies in identifying output quality control by means of productivity One of the conclusions of the article is that in today's economic situation, ignoring the existence of knowledge continuity could result in a crisis of management of knowledge and its loss. 展开更多
关键词 knowledge management knowledge continuity management knowledge competitive advantage control PRODUCTIVITY
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Knowledge, Attitude and Practices Used in the Control of Striga in Maize by Smallholder Farmers of Western Kenya
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作者 Godfrey Nakitare Nambafu Richard Ndemo Onwonga +3 位作者 George Njomo Karuku Emmanuel Safaris Ariga Bernard Vanlauwe Kristina Roing de Nowina 《Journal of Agricultural Science and Technology(B)》 2014年第3期237-248,共12页
The production of maize is constrained by parasitic weeds, particularly Striga. A study was carried out to document farmers' knowledge, attitude and practices on Striga control among smallholder farmers across three ... The production of maize is constrained by parasitic weeds, particularly Striga. A study was carried out to document farmers' knowledge, attitude and practices on Striga control among smallholder farmers across three districts: Kisumu West, Busia and Teso South of Western Kenya. A multistage sampling technique was used to select the locations and farmers to be interviewed. A semi structured, open and closed ended questionnaire was administered leading to field experiment. Besides village meetings (39.2%), farmers got informed on farming methods under Striga weed farms and its control technologies through neighbours (2.5%), workshops and trainings (5.0%), field schools (3.7%), media (7.5%) and extension agents (10.8%). The attitudes of farmers towards Striga control varied but frequently cited: long term viability of the Striga seed (12.5%), difficult to control sharing of farm tools (10.8%), expensive technologies (13.3%), lack of adequate information (18.3%), labour intensive (15.0%), large farms for use of push and pull technology (1.7%) and time consuming (12.5%). Framers used various Striga control practices but traditional methods (25%) were among the most used (25%). Concerted effort involving researchers, extension agents and private sector are, therefore, required for wide scale dissemination and adoption of the existing modem control technologies. 展开更多
关键词 ATTITUDE knowledge PRACTICE striga control technologies.
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Impact of designed infection control educational program on nurses’knowledge and compliance with standard precautions at maternity hospitals
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作者 Fatma ZAGHLOUL-MAHMOUD Mohamed GAMAL-MOSTAFA Walaa MAHMOUD-ABDEL-RAHMAN 《Journal of Integrative Nursing》 2023年第2期138-144,共7页
Objectives:This study aimed to assess the nurses’knowledge and compliance with infection control standard precautions and evaluate the impact of the designed infection control educational program on nurses’knowledge... Objectives:This study aimed to assess the nurses’knowledge and compliance with infection control standard precautions and evaluate the impact of the designed infection control educational program on nurses’knowledge and compliance with standard precautions at the maternity hospital.Materials and Methods:A quasi‑experimental one‑group pretest‑posttest design was used on convenient sample of 60 nurses working at Obstetrics and Gynecological hospital in Cairo University Hospital,Kasr El Ainy,who received“designed infection control educational program”for 6 months.The data were collected through the questionnaire comprising demographics,knowledge,and compliance with standard precautions questionnaire.The nurses’knowledge and compliance score were compared before and after intervention.Results:The studied nurses had higher level of knowledge(85.3%)and compliance(92.8%)regarding infection control standard precautions after the educational program compared to before the program.The results revealed statistically significant difference between before and after the program regarding nurses’knowledge score(15.5±2.9 vs.17.1±1.6,P<0.001)and compliance score(58.5±13.2 vs.74.3±5.1,P<0.001).In addition,there was insignificant relation between nurses’knowledge and compliance with standard precautions both before(r=0.952,P=0.474)and after educational program(r=0.164,P=0.223).Conclusion:The nurses’level of knowledge and compliance regarding infection control standard precautions was significantly improved after the program.Therefore,it is recommended that periodical educational programs regarding the standard precautions of infection control are essential for nurses at maternity hospital. 展开更多
关键词 COMPLIANCE infection control knowledge maternity nursing standard precautions
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The Construction of an Ontology-Based Knowledge Management Model for Departure Procedures
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作者 Kuo-Wei Su Chun-Hung Yang Po-Hsin Huang 《Advances in Aerospace Science and Technology》 2016年第1期32-47,共17页
With increased global economic development, the air traffic volume (including passengers and parcels) increases every year. Thus, the business-related load on air traffic controllers becomes heavier, which influences ... With increased global economic development, the air traffic volume (including passengers and parcels) increases every year. Thus, the business-related load on air traffic controllers becomes heavier, which influences their need for frequent learning and training opportunities. Therefore, the only solution is to enhance the performance of the training for the air traffic controllers (ATCs) and to build uniform training procedures and standardized training content, which constitute a shared framework with ontology knowledge. Taking departure operation control processes as an example, the research analyzes an aviation organization framework, with information communication procedures and relevant knowledge assets from the viewpoint of departure processes, to explore a knowledge management model of aviation control. This research studies how explicit knowledge is transformed by CommonKADS methodology using the CommonKADS sheet, and the Unified Modeling Language (UML) graph presentation and ontology model are discussed in this research. This analysis procedure can be applied to the systematic analysis and establishment of similar business-based information systems, allowing this research result to be further shared in different industries 展开更多
关键词 Air Traffic controllers (ATCs) Departure Procedure Ontology knowledge CommonKADS Methodology
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Control 5.0: From Newton to Merton in Popper's Cyber-Social-Physical Spaces 被引量:13
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作者 Fei-Yue Wang 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI 2016年第3期233-234,共2页
The future of control in cyberspace of parallel worlds is discussed. It argues for the coming age of Control 5.0,the control technology for the new IT capable of dealing with artificial worlds with VR, AR, AI and robo... The future of control in cyberspace of parallel worlds is discussed. It argues for the coming age of Control 5.0,the control technology for the new IT capable of dealing with artificial worlds with VR, AR, AI and robotics. The discipline of automation needs a new interpretation of its core knowledge and skill set of modeling, analysis, and control for cyber-socialphysical systems, and a paradigm shift from Newtonian Systems with Newton's Laws or Big Laws with Small Data to Mertonian Systems with Merton's Laws or Small Laws with Big Data. 展开更多
关键词 control 5.0 parallel control knowledge automation CPS CSP CPSS MERTON WIENER POPPER
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Where is the rudder of a fish?:the mechanism of swimming and control of self-propelled fish school 被引量:14
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作者 Chuijie Wu Liang Wang 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2010年第1期45-65,共21页
Numerical simulation and control of self- propelled swimming of two- and three-dimensional biomimetic fish school in a viscous flow are investigated. With a parallel computational fluid dynamics package for the two- a... Numerical simulation and control of self- propelled swimming of two- and three-dimensional biomimetic fish school in a viscous flow are investigated. With a parallel computational fluid dynamics package for the two- and three-dimensional moving boundary problem, which combines the adaptive multi-grid finite volume method and the methods of immersed boundary and volume of fluid, it is found that due to the interactions of vortices in the wakes, without proper control, a fish school swim with a given flap- ping rule can not keep the fixed shape of a queue. In order to understand the secret of fish swimming, a new feedback con- trol strategy of fish motion is proposed for the first time, i,e., the locomotion speed is adjusted by the flapping frequency of the caudal, and the direction of swimming is controlled by the swinging of the head of a fish. Results show that with this feedback control strategy, a fish school can keep the good order of a queue in cruising, turning or swimming around circles. This new control strategy, which separates the speed control and direction control, is important in the construction of biomimetic robot fish, with which it greatly simplifies the control devices of a biomimetic robot fish. 展开更多
关键词 Self-propelled swimming Feedback controlstrategy of fish swimming ~ Direction control - Locomotionspeed control Three-dimensional biomimetic fish
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Dynamics and adaptive control of a dual-arm space robot with closed-loop constraints and uncertain inertial parameters 被引量:20
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作者 Ying-Hong Jia Quan Hu Shi-Jie Xu 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2014年第1期112-124,共13页
A dynamics-based adaptive control approach is proposed for a planar dual-arm space robot in the presence of closed-loop constraints and uncertain inertial parameters of the payload. The controller is capable of contro... A dynamics-based adaptive control approach is proposed for a planar dual-arm space robot in the presence of closed-loop constraints and uncertain inertial parameters of the payload. The controller is capable of controlling the po- sition and attitude of both the satellite base and the payload grasped by the manipulator end effectors. The equations of motion in reduced-order form for the constrained system are derived by incorporating the constraint equations in terms of accelerations into Kane's equations of the unconstrained system. Model analysis shows that the resulting equations perfectly meet the requirement of adaptive controller design. Consequently, by using an indirect approach, an adaptive control scheme is proposed to accomplish position/attitude trajectory tracking control with the uncertain parameters be- ing estimated on-line. The actuator redundancy due to the closed-loop constraints is utilized to minimize a weighted norm of the joint torques. Global asymptotic stability is proven by using Lyapunov's method, and simulation results are also presented to demonstrate the effectiveness of the proposed approach. 展开更多
关键词 Space robot Dynamics. Adaptive control Closed-loop constraint Parameter uncertainty - Kane's equation
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Deformation behaviors of 21-6-9 stainless steel tube numerical control bending under different friction conditions 被引量:9
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作者 方军 鲁世强 +1 位作者 王克鲁 姚正军 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第8期2864-2874,共11页
For contact dominated numerical control(NC) bending process of tube, the effect of friction on bending deformation behaviors should be focused on to achieve precision bending forming. A three dimensional(3D) elastic-p... For contact dominated numerical control(NC) bending process of tube, the effect of friction on bending deformation behaviors should be focused on to achieve precision bending forming. A three dimensional(3D) elastic-plastic finite element(FE) model of NC bending process was established under ABAQUS/Explicit platform, and its reliability was validated by the experiment. Then, numerical study on bending deformation behaviors under different frictions between tube and various dies was explored from multiple aspects such as wrinkling, wall thickness change and cross section deformation. The results show that the large friction of wiper die-tube reduces the wrinkling wave ratio η and cross section deformation degree ΔD and increases the wall thinning degree Δt. The large friction of mandrel-tube causes large η, Δt and ΔD, and the onset of wrinkling near clamp die. The large friction of pressure die-tube reduces Δt and ΔD, and the friction on this interface has little effect on η. The large friction of bending die-tube reduces η and ΔD, and the friction on this interface has little effect on Δt. The reasonable friction coefficients on wiper die-tube, mandrel-tube, pressure die-tube and bending die-tube of 21-6-9(0Cr21Ni6Mn9N) stainless steel tube in NC bending are 0.05-0.15, 0.05-0.15, 0.25-0.35 and 0.25-0.35, respectively. The results can provide a guideline for applying the friction conditions to establish the robust bending environment for stable and precise bending deformation of tube bending. 展开更多
关键词 21-6-9 stainless steel tube FRICTION deformation behaviors numerical control bending finite element simulation
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CO_2-triggered gelation for mobility control and channeling blocking during CO_2 flooding processes 被引量:7
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作者 De-Xiang Li Liang Zhang +2 位作者 Yan-Min Liu Wan-Li Kang Shao-Ran Ren 《Petroleum Science》 SCIE CAS CSCD 2016年第2期247-258,共12页
CO2 flooding is regarded as an important method for enhanced oil recovery (EOR) and greenhouse gas control. However, the heterogeneity prevalently dis- tributed in reservoirs inhibits the performance of this technol... CO2 flooding is regarded as an important method for enhanced oil recovery (EOR) and greenhouse gas control. However, the heterogeneity prevalently dis- tributed in reservoirs inhibits the performance of this technology. The sweep efficiency can be significantly reduced especially in the presence of "thief zones". Hence, gas channeling blocking and mobility control are important technical issues for the success of CO2 injection. Normally, crosslinked gels have the potential to block gas channels, but the gelation time control poses challenges to this method. In this study, a new method for selectively blocking CO2 channeling is proposed, which is based on a type of CO2-sensitive gel system (modified polyacry- lamide-methenamine-resorcinol gel system) to form gel in situ. A CO2-sensitive gel system is when gelation or solidification will be triggered by CO2 in the reservoir to block gas channels. The CO2-sensitivity of the gel system was demonstrated in parallel bottle tests of gel in N2 and CO2 atmospheres. Sand pack flow experiments were con- ducted to investigate the shutoff capacity of the gel system under different conditions. The injectivity of the gel system was studied via viscosity measurements. The results indi- cate that this gel system was sensitive to CO2 and had good performance of channeling blocking in porous media. Advantageous viscosity-temperature characteristics were achieved in this work. The effectiveness for EOR in heterogeneous formations based on this gel system was demonstrated using displacement tests conducted in double sand packs. The experimental results can provide guideli- nes for the deployment of theCO2-sensitive gel system for field applications. 展开更多
关键词 CO2 flooding Gas channeling - CO2sensitivity - Sweep efficiency Enhanced oil recoveryMobility control
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