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Study on Independent Supervision Function of Design Assurance System
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作者 SUI Lijun MA Congyao WANG Jianyuan 《International Journal of Plant Engineering and Management》 2024年第3期185-192,共8页
The effective operation of a design assurance system cannot be achieved without the effective performance of the independent supervision function.As one of the core functions of the design assurance system,the purpose... The effective operation of a design assurance system cannot be achieved without the effective performance of the independent supervision function.As one of the core functions of the design assurance system,the purpose of the independent supervision function is to ensure that the system operates within the scope of procedures and manuals.At present,the function of independent supervision is a difficult and confusing issue for various original equipment manufacturers as well as suppliers,and there is an urgent requirement to put forward relevant requirements and form relevant methods.Based on the above mentioned objective,the basic requirements of the independent supervision function of design assurance system were studied,the problems and deficiencies in the organization,staffing,and methods existing in the current independent supervision function were analyzed,the improvement suggestions and measures for the performance of the independent supervision function from the aspects of the organization,staffing,procedures,and suppliers were put forward.The present work and conclusions provide guidance and direction for the effective operation of the design assurance system. 展开更多
关键词 design of assurance systems independent supervision functions system operation internal audits SUPPLIERS
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Construction and Practice of Education and Teaching Quality Assurance Systems in Applied Colleges and Universities under the Background of Digital Intelligence
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作者 Hui Cheng 《Journal of Contemporary Educational Research》 2024年第9期265-270,共6页
This paper discusses the optimization strategy of education and teaching quality assurance systems in applied colleges and universities under the background of digital intelligence.It first summarizes the relevant the... This paper discusses the optimization strategy of education and teaching quality assurance systems in applied colleges and universities under the background of digital intelligence.It first summarizes the relevant theories of digital intelligence transformation and analyzes the impact of digital intelligence transformation on higher education.Secondly,this paper puts forward the principles of constructing the quality assurance system of applied colleges,including strengthening the quality assurance consciousness,improving teachers’digital literacy,and implementing digital intelligence governance.From the practical perspective,this paper expounds on strategies such as optimizing educational teaching resource allocation,constructing a diversified evaluation system of teaching quality,strengthening the construction and training of teaching staff,and innovating teaching management methods.Specific optimization measures are put forward,such as improving policies,regulations,and system guarantees,strengthening cooperation between schools and enterprises,integrating industry,school,and research,building an educational information platform,and improving the monitoring and feedback mechanism of educational quality. 展开更多
关键词 Digital intelligence transformation Applied colleges and universities Education and teaching quality assurance system Optimization strategy
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QUALITY ASSURANCE INFORMATION SYSTEM FOR AGILE MANUFACTURING
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作者 孙蓓蓓 钟秉林 +2 位作者 崔敏 黄仁 A kif A.Bulgak 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2000年第1期71-77,共7页
The customer driven dynamic global market and geographical distribution of collaborating partners bring new challenges to the development of quality assurance information system (QAIS) for agile manufacturing. With re... The customer driven dynamic global market and geographical distribution of collaborating partners bring new challenges to the development of quality assurance information system (QAIS) for agile manufacturing. With recent dramatic advances in information technology, firstly the requirements of QAIS are examined in agile manufacturing environment, then a new implementation framework of a distributed QAIS is presented, where a deve loping environment of QAIS is established and some critical techniques are studied. Finally a prototype system based on world wide web (WWW) is accomplished. 展开更多
关键词 QUALITY quality control information system quality assurance agile manufacturing INTERNET INTRANET
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ASSURE理念下思政教育走进大学英语翻转课堂 被引量:1
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作者 韩智玲 《湖北开放职业学院学报》 2024年第3期123-125,共3页
随着课程思政走进大学英语课堂,英语教师要改变传统的教学模式,在ASSURE教学理念的指导下,以山东科技职业学院思政版PPT为研究对象,从分析学习者、陈述教学目标、选择教学方法、媒体和材料、使用媒体和材料、要求学习者参与、评价和修... 随着课程思政走进大学英语课堂,英语教师要改变传统的教学模式,在ASSURE教学理念的指导下,以山东科技职业学院思政版PPT为研究对象,从分析学习者、陈述教学目标、选择教学方法、媒体和材料、使用媒体和材料、要求学习者参与、评价和修正等六个方面分析其思政素材对于大学英语课程思政的意义。探讨了大学英语课程思政的不足之处,以便更好地在该理念的指导下让课程思政走进翻转课堂。 展开更多
关键词 assurE教学理念 翻转课堂 课程思政
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ASSURE模型在高职商务英语课程思政教学中的应用
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作者 左小娟 《浙江交通职业技术学院学报》 CAS 2024年第2期66-70,86,共6页
在高职商务英语课程教学中落实课程思政要求,融入中国式现代化战略思想、中华传统优秀文化,有利于增强学生的爱国热情和民族文化自信。本文以ASSURE模型为指导框架,挖掘教学主题和内容中的思政元素,从六个环节进行教学设计,采用线上线... 在高职商务英语课程教学中落实课程思政要求,融入中国式现代化战略思想、中华传统优秀文化,有利于增强学生的爱国热情和民族文化自信。本文以ASSURE模型为指导框架,挖掘教学主题和内容中的思政元素,从六个环节进行教学设计,采用线上线下、课堂内外、校内校外“三结合”的教学路径。在商务英语教学中融入基于职业导向的思政教育,强化学生商务英语语言技能的同时,注重提升学生的职业素养和道德品质,促进学生全面发展。 展开更多
关键词 assurE模型 “三结合”教学路径 职业导向 课程思政
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Quality assurance and quality control in the laboratory andrology 被引量:26
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作者 Allan A. Pacey 《Asian Journal of Andrology》 SCIE CAS CSCD 2010年第1期21-25,共5页
Quality assurance (QA) and quality control (QC) are fundamental aspects of any laboratory measurement. However, in comparison with other medical disciplines, the need for QA and QC in laboratory andrology has been... Quality assurance (QA) and quality control (QC) are fundamental aspects of any laboratory measurement. However, in comparison with other medical disciplines, the need for QA and QC in laboratory andrology has been recognized only recently. Furthermore, there is evidence that the effort required to undertake QA and QC has not been wholly welcomed by some clinicians. Nevertheless, accrediting bodies and regulatory authorities increasingly require evidence that laboratories have effective QA and QC measures in place because both are central to the quality management processes. Following the publication of the 5th edition of the World Health Organization Laboratory Manual, existing QA and QC systems will need to be updated to take into account some of the methodological changes recommended by the manual. Three of these are discussed in this commentary; they relate to: (i) the move to infer semen volume from its weight; (ii) the re-classification of sperm motility grades from four to three; and (iii) the publication of a lower reference limit for morphology of 4% (with a corresponding 95% confidence interval of 3%-4%). The importance of QA and QC in all laboratory tests, including up and coming new tests to assess sperm DNA integrity, is discussed. The need for adequate initial training and continuing professional development programmes to support laboratory scientists performing andrology is also described. 展开更多
关键词 ANDROLOGY health care quality assurance quality control semen analysis
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Advances in rheology and flow assurance studies of waxy crude 被引量:11
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作者 Zhang Jinjun Yu Bo +1 位作者 Li Hongying Huang Qiyu 《Petroleum Science》 SCIE CAS CSCD 2013年第4期538-547,共10页
Flow assurance is one of the core issues in safe and economical operation of waxy crude pipelines.Its essence lies in flow and heat transfer of the crude.In the past 10 years,the authors' team has achieved a lot of i... Flow assurance is one of the core issues in safe and economical operation of waxy crude pipelines.Its essence lies in flow and heat transfer of the crude.In the past 10 years,the authors' team has achieved a lot of innovative results in aspects of waxy crude rheology,flow assurance assessment,and pipelining technologies on the basis of decades of studies.The rheological characteristics of waxy crude are much better understood,and a method for quantitatively simulating the effect of flow shear was developed based on some theoretical breakthroughs.Studies of the mechanism of waxy crude rheology have been deepened to the quantitative level.After successful development of efficient numericalalgorithms,accurate simulations have been achieved for various complex flow and heat transfer situations in waxy crude pipelining,and a reliability-based approach to flow assurance assessment has been set up.New pipelining technologies have been developed such as batching pour-point depressant-(PPD-) treated multiple-waxy-crudes,intermittent transport of waxy crudes through long-distance pipelines,and batching hot and cold crudes.By their application,a series of problems hindering safe,efficient and flexible operation of waxy crude pipelines were tackled,demonstrating that transportation technologies for waxy crude have advanced to a new and high level. 展开更多
关键词 Waxy crude pipeline transportation flow assurance RHEOLOGY numerical simulation
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A model for estimating flow assurance of hydrate slurry in pipelines 被引量:11
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作者 Wuchang Wang Shuanshi Fan +1 位作者 Deqing Liang Yuxing Li 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2010年第4期380-384,共5页
The problem of hydrate blockage of pipelines in offshore production is becoming ever-increasing severe because oil fields in ever-increasing unusual environments have been brought in production.HCFC-141b and THF were ... The problem of hydrate blockage of pipelines in offshore production is becoming ever-increasing severe because oil fields in ever-increasing unusual environments have been brought in production.HCFC-141b and THF were selected as the substitutes to study the flow assurance of the hydrates in pipelines.There are critical hydrate volume concentrations for these two slurries.Hydrate slurries behave like Bingham fluids and have high agglomerating tendency when the hydrate volume concentrations are larger than the critical ones.Based on rheological behaviors of these two hydrates,a non-dimensional parameter is proposed through studying the driving forces of agglomeration among hydrate particles,which shows the agglomerating probability of hydrate particles in pipeline and can be used to judge the safety of the pipeline.Moreover,a safe model to judge the safely flow hydrate slurries was presented and verified with the experimental data,which demonstrates that the model is effective to judge whether the pipeline can be run safely or not. 展开更多
关键词 hydrate slurry flow assurance rheological behavior safe model
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A Quality Assurance Procedure and Evaluation of Rainfall Estimates for C-Band Polarimetric Radar 被引量:8
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作者 HU Zhiqun LIU Liping WANG Lirong 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2012年第1期144-156,共13页
A mobile C-band dual polarimetric weather radar J type (PCDJ), which adopts simultaneous transmission and simultaneous reception (STSR) of horizontally and vertically polarized signals, was first developed in Chin... A mobile C-band dual polarimetric weather radar J type (PCDJ), which adopts simultaneous transmission and simultaneous reception (STSR) of horizontally and vertically polarized signals, was first developed in China in 2008. It was deployed in the radar observation plan in the South China Heavy Rainfall Experiment (SCHeREX) in the summer of 2008 and 2009, as well as in Tropical Western Pacific Ocean Observation Experiments and Research on the Predictability of High Impact Weather Events from 2008 to 2010 in China (TWPOR). Using the observation data collected in these experiments, the radar systematic error and its sources were analyzed in depth. Meanwhile an algorithm that can smooth differential propagation phase (~Dp) for estimating the high-resolution specific differential phase (KDP) was developed. After attenuation correction of reflectivity in horizontal polarization (ZH) and differential reflectivity (ZDR) of PCDJ radar by means of KDP, the data quality was improved significantly. Using quality-controlled radar data, quantitative rainfall estimation was performed, and the resutls were compared with rain-gauge measurements. A synthetic ZH /KDp-based method was analyzed. The results the traditional ZH-based method when the rain suggest that the synthetic method has the advantage over rate is 〉5 mm h^-1. The more intensive the rain rates, the higher accuracy of the estimation. 展开更多
关键词 quality assurance rainfall estimates C-band polarimetric radar
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Development of the Supply Chain Oriented Quality Assurance System for Aerospace Manufacturing SMEs and Its Implementation Perspectives 被引量:1
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作者 HUSSEIN Abdullahi CHENG Kai 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2016年第6期1067-1073,共7页
Aerospace manufacturing SMEs are continuously facing the challenge on managing their supply chain and complying with the aerospace manufacturing quality standard requirement due to their lack of resources and the natu... Aerospace manufacturing SMEs are continuously facing the challenge on managing their supply chain and complying with the aerospace manufacturing quality standard requirement due to their lack of resources and the nature of business. In this paper, the ERP system based approach is presented to quality control and assurance work in light of seamless integration of in-process production data and information internally and therefore managing suppliers more effectively and efficiently. The Aerospace Manufacturing Quality Assurance Standard (BS/EN9100) is one of the most recognised and essential protocols for developing the industry-operated-and-driven quality assurance systems. The research investigates using the ERP based system as an enabler to implement BS/EN9100 quality management system at manufacturing SMEs and the associated implementation and application perspectives. An application case study on a manufacturing SME is presented by using the SAP based implementation, which helps fiarther evaluate and validate the approach and application system development. 展开更多
关键词 BS/EN 9100 Quality assurance aerospace manufacturing ERP system aerospace quality assurance SAP programming
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Development and Challenge of HIV/AIDS Testing Laboratory Network and Quality Assurance System in China 被引量:4
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作者 Yan JIANG 《Virologica Sinica》 SCIE CAS CSCD 2007年第6期434-442,共9页
This paper describes the development and challenge of HIV/AIDS testing laboratory network and quality assurance system in China. At present,the HIV/AIDS testing laboratories includes three classes,the National AIDS Re... This paper describes the development and challenge of HIV/AIDS testing laboratory network and quality assurance system in China. At present,the HIV/AIDS testing laboratories includes three classes,the National AIDS Reference Laboratory,HIV/AIDS confirmatory laboratories and HIV/AIDS screening laboratories. All of them are accredited by the health authorities,and each class of laboratories take charge of their function strictly according to the "National Management of HIV/AIDS Detection (2006)". A complete quality assurance and quality control system for HIV/AIDS testing has been developed,which includes technical training,strict laboratory monitoring and approval,examination or proficiency testing on HIV/AIDS detection,and quality evaluation and supervision of HIV/AIDS diagnostic kits. Besides conduct the routine anti-HIV antibody test,more and more laboratories began to conduct other tests,such as CD4+ T lymphocyte cell counting,HIV viral load,HIV DNA PCR,genotyping,drug resistance,and HIV-1 recent infection test. The primary challenges faced by the HIV/AIDS testing laboratory network are in the areas of laboratory management and quality control. For example,the provincial PT program is inefficient,the internal quality control is conducted perfunctorily,personnel training can not met the needs of the workplace,which need to be improved. 展开更多
关键词 Human immunodeficiency virus (HIV) LABORATORY Detection Quality assurance Quality control
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The Quality of Medicines in Community Pharmacies in Riyadh, Saudi Arabia: A Lot Quality Assurance Sampling (LQAS)-Based Survey 被引量:2
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作者 Hani M. J. Khojah Henrik Pallos +3 位作者 Naoko Yoshida Manabu Akazawa Hirohito Tsuboi Kazuko Kimura 《Pharmacology & Pharmacy》 2013年第7期511-519,共9页
Objectives: To classify community pharmacies (CPs) in Riyadh, Saudi Arabia, in terms of the quality of medicines sold by them, using?the lot quality assurance sampling (LQAS) technique with a predefined threshold. Met... Objectives: To classify community pharmacies (CPs) in Riyadh, Saudi Arabia, in terms of the quality of medicines sold by them, using?the lot quality assurance sampling (LQAS) technique with a predefined threshold. Methods: Riyadh CPs were divided into 2 categories (“lots” for the purpose of LQAS), i.e., chain and independent CPs. Upper and lower rate thresholds for CPs that sell low-quality medicines were predefined as 20% and 5%, respectively. Consumer and provider risks were predefined as 0.05 and 0.10, respectively. The calculated number of randomly selected CPs required in each lot was 36;then, sale of low-quality medicines in >3 CPs implies a prevalence of >20% of such CPs according to LQAS. A randomly selected brand of amoxicillin (selected as a quality indicator of medicines because it is both widely counterfeited and heat-sensitive) was purchased from each pharmacy by a “mystery shopper”, checked for authenticity, and analyzed for drug content and content uniformity using a validated HPLC method. Results: Substandard amoxicillin was purchased in 9 pharmacies (4 chains and 5 independent). Both lots were thus rejected as unacceptable, which may indicate that consumers in Riyadh are at risk of purchasing substandard medicines at CPs. Conclusions: The quality of medicines sold in CPs in Riyadh did not meet our acceptability criterion, and appropriate intervention by decision makers is recommended. LQAS proved to be a practical, economical, and statistically valid sampling method for surveying the quality of medicines. It should enable decision makers to allocate resources for improvement more efficiently. 展开更多
关键词 AMOXICILLIN Antibiotic QUALITY of Medicines Lot QUALITY assurance Sampling SAUDI ARABIA Community PHARMACY
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An Effective and Secure Quality Assurance System for a Computer Science Program 被引量:1
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作者 Mohammad Alkhatib 《Computer Systems Science & Engineering》 SCIE EI 2022年第6期975-995,共21页
Improving the quality assurance (QA) processes and acquiring accreditation are top priorities for academic programs. The learning outcomes (LOs)assessment and continuous quality improvement represent core components ... Improving the quality assurance (QA) processes and acquiring accreditation are top priorities for academic programs. The learning outcomes (LOs)assessment and continuous quality improvement represent core components ofthe quality assurance system (QAS). Current assessment methods suffer deficiencies related to accuracy and reliability, and they lack well-organized processes forcontinuous improvement planning. Moreover, the absence of automation, andintegration in QA processes forms a major obstacle towards developing efficientquality system. There is a pressing need to adopt security protocols that providerequired security services to safeguard the valuable information processed byQAS as well. This research proposes an effective methodology for LOs assessment and continuous improvement processes. The proposed approach ensuresmore accurate and reliable LOs assessment results and provides systematic wayfor utilizing those results in the continuous quality improvement. This systematicand well-specified QA processes were then utilized to model and implement automated and secure QAS that efficiently performs quality-related processes. Theproposed system adopts two security protocols that provide confidentiality, integrity, and authentication for quality data and reports. The security protocols avoidthe source repudiation, which is important in the quality reporting system. This isachieved through implementing powerful cryptographic algorithms. The QASenables efficient data collection and processing required for analysis and interpretation. It also prepares for the development of datasets that can be used in futureartificial intelligence (AI) researches to support decision making and improve thequality of academic programs. The proposed approach is implemented in a successful real case study for a computer science program. The current study servesscientific programs struggling to achieve academic accreditation, and gives rise tofully automating and integrating the QA processes and adopting modern AI andsecurity technologies to develop effective QAS. 展开更多
关键词 Quality assurance information security cryptographic algorithms education programs
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A novel method for geometric quality assurance of rock joint replicas in direct shear testing-Part 1:Derivation of quality assurance parameters and geometric reproducibility 被引量:1
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作者 J.Larsson F.Johansson +3 位作者 D.Mas Ivars E.Johnson M.Flansbjer N.W.Portal 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2023年第9期2193-2208,共16页
Since each rock joint is unique by nature,the utilization of replicas in direct shear testing is required to carry out experimental parameter studies.However,information about the ability of the replicas to simulate t... Since each rock joint is unique by nature,the utilization of replicas in direct shear testing is required to carry out experimental parameter studies.However,information about the ability of the replicas to simulate the shear mechanical behavior of the rock joint and their dispersion in direct shear testing is lacking.With the aim to facilitate generation of high-quality direct shear test data from replicas,a novel component in the testing procedure is introduced by presenting two parameters for geometric quality assurance.The parameters are derived from surface comparisons of three-dimensional(3D)scanning data of the rock joint and its replicas.The first parameter,smf,captures morphological deviations between the replica and the rock joint surfaces.smf is derived as the standard deviation of the deviations between the coordinate points of the replica and the rock joint.Four sources of errors introduced in the replica manufacturing process employed in this study could be identified.These errors could be minimized,yielding replicas with smf0.06 mm.The second parameter is a vector,VHp100,which describes deviations with respect to the shear direction.It is the projection of the 100 mm long normal vector of the best-fit plane of the replica joint surface to the corresponding plane of the rock joint.VHp100was found to be less than or equal to 0.36 mm in this study.Application of these two geometric quality assurance parameters demonstrates that it is possible to manufacture replicas with high geometric similarity to the rock joint.In a subsequent paper(part 2),smf and VHp100 are incorporated in a novel quality assurance method,in which the parameters shall be evaluated prior to direct shear testing.Replicas having parameter values below established thresholds shall have a known and narrow dispersion and imitate the shear mechanical behavior of the rock joint. 展开更多
关键词 Three-dimensional(3D)scanning Geometric reproducibility Geometric quality assurance Replicas Rock joint Surface comparisons
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以Audit and Assurance课程为例的双语课程教学改革研究 被引量:3
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作者 王佳一 《河南教育(高教版)(中)》 2019年第2期72-74,共3页
改革开放以来,我国进出口贸易规模不断扩大,这在客观上要求我国加快财务准则的国际化。作为未来人才培养的载体,我国财经类高校纷纷开设双语课程,以培养国际化人才。本研究以Audit and Assurance课程为例,对双语课程在教学改革中的实践... 改革开放以来,我国进出口贸易规模不断扩大,这在客观上要求我国加快财务准则的国际化。作为未来人才培养的载体,我国财经类高校纷纷开设双语课程,以培养国际化人才。本研究以Audit and Assurance课程为例,对双语课程在教学改革中的实践进行了阐述,并提出了实践中存在的问题,最后给出相应的对策和建议。 展开更多
关键词 AUDIT and assurance 双语课程 教学改革
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Study on Evaluation of Supplier's Quality Assurance System
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作者 GAO Zhi-yong, GAO Jian-min, CHEN Fu-min (CIMS Center, Xi’an Jiaotong University, Xi’an 710049, China) 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 2002年第S1期230-,共1页
To be a worldwide competitor, enterprise needs to e va luate and select its supplier carefully. Generally, to evaluate a supplier, the evaluating effort is focused on the purchase price, delivery time, product quali t... To be a worldwide competitor, enterprise needs to e va luate and select its supplier carefully. Generally, to evaluate a supplier, the evaluating effort is focused on the purchase price, delivery time, product quali ty, etc. The vendors’ quality assurance is seldom considered. However, it reflec ts the ability that a vendor can provide high quality but low cost products cont inuously and stably. In this paper, with the study on evaluation of supplier’s q uality assurance system, a set of methods and indices to supplier’s quality assu rance evaluation is introduced. The indices construct an index system, which is based on the ISO9000 series standards. According to the problem’s character and the requirement of evaluation, all the evaluation indices are set off to three k inds: general index, functional index and protective index. And the evaluation m ethod combines quantitative analysis with qualitative analysis. Firstly, a sensi tive factor model is constructed to estimate the contribution of factors that ha ve key effect on synthetic evaluation in supplier’s quality system. Then, those suppliers having low evaluating value are rejected. Secondly, fuzzy logic is int roduced to evaluate other suppliers synthetically. The rest suppliers are compar able. So, supplier’s quality assurance system can be evaluated in quantity. Afte r unification works, the evaluated suppliers can be ranked. And the best vendor can be selected out intuitively. 展开更多
关键词 supplier evaluation quality assurance system Fu zzy logic
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Establishment of a Quality Assurance System in the Online Monitoring of Electromagnetic Environment of Alternating Current Power Transmission and Transformation Facilities
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作者 Li Peiming Xiao Jun Wu Shaohua 《Meteorological and Environmental Research》 CAS 2019年第5期46-50,共5页
With the acceleration of urbanization and increase of points in power systems,complaints about power grids have increased.In the actual on-site measurement process,although the actual measurement results can meet the ... With the acceleration of urbanization and increase of points in power systems,complaints about power grids have increased.In the actual on-site measurement process,although the actual measurement results can meet the relevant standards,some people are still concerned that the electromagnetic environment may change drastically outside the measurement period,which will have an impact on human health.In this study,the situation of electromagnetic online monitoring systems at home and abroad was introduced firstly,and then some practical requirements for establishing monitoring stations were analyzed.According to existing technologies and related writings,the methods and steps for establishing a quality assurance system were introduced,including the identification of quality assurance system activities and their corresponding structure of quality assurance system documents,the preparation and principles of the documents,and the operation of the quality assurance system.It intends to provide reference for the relevant organizations and personnel conducting electromagnetic environment monitoring when establishing a quality assurance system.Through the establishment of the online monitoring system and the later data publicity,the public have an intuitive understanding of the electromagnetic environment attenuation around power transmission and transformation projects,which can not only make China's electric power industry develop better,but also monitor the unexpected situation in time,maintain public safety and reduce people's fear of electromagnetic radiation in substations. 展开更多
关键词 ELECTROMAGNETIC ONLINE monitoring SUBSTATION QUALITY assurance system Safety
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An evaluation of quality assurance to monitor acid precipitation by using ion balance in Guizhou,China
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作者 Kang Demeng(Research Center for Eco- Environniental Sciences. ChineseAcademy of Sciences. Beijing100085 . China) 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 1995年第3期368-373,共6页
AnevaluationofqualityassurancetomonitoracidprecipitationbyusingionbalanceinGuizhou,ChinaKangDemeng(ResearchC... AnevaluationofqualityassurancetomonitoracidprecipitationbyusingionbalanceinGuizhou,ChinaKangDemeng(ResearchCenterforEco-Envir... 展开更多
关键词 acid precipitation: ion balance quality assurance.
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A Quality Assurance Approach for Linear Accelerator Mechanical Isocenters with Portal Images
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作者 Qiyong Fan Sumin Zhou +2 位作者 Yu Lei Sicong Li Mutian Zhang 《International Journal of Medical Physics, Clinical Engineering and Radiation Oncology》 2018年第1期100-114,共15页
Purpose: With usually a millimeter-level PTV margin, stereotactic radiosurgery (SRS) and stereotactic body radiation therapy (SBRT) pose a stringent requirement on the isocentricity of the Linac. This requirement is p... Purpose: With usually a millimeter-level PTV margin, stereotactic radiosurgery (SRS) and stereotactic body radiation therapy (SBRT) pose a stringent requirement on the isocentricity of the Linac. This requirement is partly fulfilled by routine isocenter quality assurance (QA) test to verify the size and location of the isocenter. The current common QA methods such as spoke shot were developed before SBRT/SRS became popular and when IGRT was largely absent and hence have their limitations. In this work, we describe an isocenter QA approach based on portal imaging to provide the community with a superior alternative. Methods: The proposed approach utilizes a BrainLab ball bearing (BB) phantom in conjunction with an electronic portal imaging devices (EPID) imager. The BB phantom was first aligned with a calibrated room laser system. Portal images were then acquired using 6 MV beam with a 2 × 2 cm2 open field and a 15 mm cone on a Varian TrueBeam STx machine. The gantry, collimator, and table were rotated separately at selected angles to acquire a series of portal images in order to determine the isocenter of each rotating system. The location and diameter of these isocenters were determined by calculating the relative displacement of either BB or open field edge between the acquired EPID images. The demonstration of the reproducibility and robustness of this EPID-based approach was carried out by repeating measurements 10 times independently for each rotating system and simulating clinical scenarios of asymmetric jaws and misalignment of BB phantom, respectively. Results: For our TrueBeam STx machine, the isocenter diameter derived from open-field EPID images was roughly 0.15 mm, 0.18 mm, 0.49 mm for the collimator, table, and gantry, respectively. For the collimator and gantry, images taken with the cone gave considerably smaller isocenter diameter. Results remained almost unchanged despite the presence of simulated BB misalignment and asymmetric jaws error, and between independent measurements. Isocenter location and diameter derived from images obtained at a limited number of angles (≤11) were adequately accurate to represent those derived from images of densely sampled angles. Conclusions: An EPID-based isocenter QA approach is described and demonstrated to be accurate, robust, and reproducible. This approach provides a superior alternative to conventional isocenter QA methods with no additional cost. It can be implemented with convenience for any linear accelerator with an EPID imager. 展开更多
关键词 Linear Accelerator ISOCENTER MECHANICAL CHECK Quality assurance SPOKE Shot
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Quality Assurance for Respiratory-Gated Radiotherapy Using the Real-Time Tumor-Tracking Radiotherapy System
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作者 Takehiro Shiinoki Shinji Kawamura +9 位作者 Takuya Uehara Yuki Yuasa Takeshi Kamomae Takaya Kotakebayashi Masahiro Koike Ryuji Kanzaki Sung Chul Park Hideki Hanazawa Shotaro Takahashi Keiko Shibuya 《International Journal of Medical Physics, Clinical Engineering and Radiation Oncology》 2014年第3期125-132,共8页
Purpose: Respiratory-gated radiation therapy (RT) using the real-time tumor-tracking radiotherapy (RTRT) system is an effective technique for managing tumor motion. High dosimetric and geometric accuracy is needed;how... Purpose: Respiratory-gated radiation therapy (RT) using the real-time tumor-tracking radiotherapy (RTRT) system is an effective technique for managing tumor motion. High dosimetric and geometric accuracy is needed;however, quality assurance (QA) for respiratory-gated RT using the RTRT system has not been reported. The purpose of this study was to perform QA for respiratorygated RT using the RTRT system. Materials and Methods: The RTRT system detected the position of the fiducial marker and radiation delivery gated to the motion of the marker was performed. The dynamic anthropomorphic thorax phantom was positioned at the isocenter using the fiducial marker in the phantom. The phantom was irradiated only when the fiducial marker was within a three-dimensional gating window of ±2 mm from the planned position. First, the absolute doses were measured using anionization chamber inserted in the phantom under the stationary, gating and non-gating state for sinusoidal (nadir-to-peak amplitude [A]: 20 - 40 mm, breathing period [T]: 2 - 4 s) and the basic respiratory patterns. Second, the dose profiles were measured using Gafchromic films in the phantom under the same conditions. Differences between dose profiles were calculated to evaluate the dosimetric and geometric accuracy. Finally, differences between the actual and measured position of the fiducial marker were calculated to evaluate the tracking accuracy for sinusoidal and basic respiratory patterns. Results: For the sinusoidal patterns, the relative doses were 0.93 for non-gating and 0.99 for gating (A = 20 mm, T = 2 s), 0.94 for non-gating and 1.00 for gating (A = 20 mm, T = 4 s), 0.55 for non-gating and 1.00 for gating (A = 40 mm, T = 4 s), respectively. For the basic respiratory pattern, the relative doses were 1.00 for non-gating and 1.00 for gating, respectively. Compared to the stationary conditions, the differences in lateral distance between the 90% dose of dose profiles were 6.23 mm for non-gating and 0.36 mm for gating (A = 20 mm, T = 2 s), 8.79 mm for non-gating and 1.73 mm for gating (A = 20 mm, T = 4 s), 18.37 mm for non-gating and 0.67 mm for gating (A = 40 mm, T = 4 s), respectively. For the basic respiratory pattern, those were 5.23 mm for non-gating and 0.35 mm for gating. The root mean square (RMS) values of the tracking error were 0.18 mm (A = 20 mm, T = 2 s), 0.14 mm (A = 20 mm, T = 4 s), and 0.21 mm (A = 40 mm, T = 4 s) for sinusoidal and 0.79 mm for the basic respiratory pattern, respectively. Conclusion: We conducted QA for respiratory-gated RT using the RTRT system. The respiratory-gated RT using the RTRT system reduced the blurring effects on dose distribution with high dosimetric and geometric accuracy. 展开更多
关键词 Quality assurance RESPIRATORY GATING REAL-TIME Tumor-Tracking RADIOTHERAPY SYSTEM
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