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A Data Assured Deletion Scheme in Cloud Storage 被引量:7
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作者 LI Chaoling CHEN Yue ZHOU Yanzhou 《China Communications》 SCIE CSCD 2014年第4期98-110,共13页
In order to provide a practicable solution to data confidentiality in cloud storage service,a data assured deletion scheme,which achieves the fine grained access control,hopping and sniffing attacks resistance,data dy... In order to provide a practicable solution to data confidentiality in cloud storage service,a data assured deletion scheme,which achieves the fine grained access control,hopping and sniffing attacks resistance,data dynamics and deduplication,is proposed.In our scheme,data blocks are encrypted by a two-level encryption approach,in which the control keys are generated from a key derivation tree,encrypted by an All-OrNothing algorithm and then distributed into DHT network after being partitioned by secret sharing.This guarantees that only authorized users can recover the control keys and then decrypt the outsourced data in an ownerspecified data lifetime.Besides confidentiality,data dynamics and deduplication are also achieved separately by adjustment of key derivation tree and convergent encryption.The analysis and experimental results show that our scheme can satisfy its security goal and perform the assured deletion with low cost. 展开更多
关键词 cloud storage data confidentiality secure data assured deletion data dynamics
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美国对中国产Assured牌烫伤急救凝胶实施召回
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《中国标准导报》 2016年第1期27-27,共1页
12月10日,美国消费品安全委员会(CPSC)和Dollar Tree公司联合宣布对中国产Assured牌烫伤急救凝胶实施自愿性召回。被召回产品的英文名称为:Assured Burn Relief Gel,是Dollar Tree公司销售的烫伤急救凝胶。产品为蓝色纸盒装,盒上印有... 12月10日,美国消费品安全委员会(CPSC)和Dollar Tree公司联合宣布对中国产Assured牌烫伤急救凝胶实施自愿性召回。被召回产品的英文名称为:Assured Burn Relief Gel,是Dollar Tree公司销售的烫伤急救凝胶。产品为蓝色纸盒装,盒上印有"Burn Relief"白色英文字母和"Burn Relief Gel"红色英文字母。 展开更多
关键词 assured 消费品安全 CPSC STORES 零售商店 召回原因 儿童安全 事故报告 多卡因 中含
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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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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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SYSTEM RELIABILITY OF ASSURED ACCURACY RATE FOR MULTI-STATE COMPUTER NETWORKS FROM SERVICE LEVEL AGREEMENTS VIEWPOINT 被引量:1
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作者 Yi-Kuei Lin Cheng Fu Huang 《Journal of Systems Science and Systems Engineering》 SCIE EI CSCD 2014年第2期196-211,共16页
From the viewpoint of service level agreements, the transmission accuracy rate is one of critical performance indicators to assess internet quality for system managers and customers. Under the assumption that each arc... From the viewpoint of service level agreements, the transmission accuracy rate is one of critical performance indicators to assess internet quality for system managers and customers. Under the assumption that each arc's capacity is deterministic, the quickest path problem is to find a path sending a specific of data such that the transmission time is minimized. However, in many real-life networks such as computer networks, each arc has stochastic capacity, lead time and accuracy rate. Such a network is named a multi-state computer network. Under both assured accuracy rate and time constraints, we extend the quickest path problem to compute the probability that d units of data can be sent through multiple minimal paths simultaneously. Such a probability named system reliability is a performance indicator to provide to managers for understanding the ability of system and improvement. An efficient algorithm is proposed to evaluate the system reliability in terms of the approach of minimal paths. 展开更多
关键词 assured accuracy rate service level agreement (SLA) transmission time multi-state computer network (MSCN) system reliability
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基于ASSURE模型的大学英语课程思政教学改革研究
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作者 朱计峰 刘俊辉 《教师》 2024年第13期60-62,共3页
在大学英语教学中融入课程思政,是新时代立德树人教育践行的重要途径。ASSURE模型最初由美国教育技术专家海涅克等人提出,六个大写字母分别代表模式中的六个环节。文章基于课程思政教育背景,对模型中的每个字母赋予新的涵义,即分析学习... 在大学英语教学中融入课程思政,是新时代立德树人教育践行的重要途径。ASSURE模型最初由美国教育技术专家海涅克等人提出,六个大写字母分别代表模式中的六个环节。文章基于课程思政教育背景,对模型中的每个字母赋予新的涵义,即分析学习者思政融入点、陈述思政育人目标、选择思政教法与媒体、使用思政教学平台、规范思政教学过程。该教学模式充分发挥新媒体、新技术和新材料的优势,打造课程思政育人新剧本,有助于培养学生的思辨能力,帮助其树立正确的价值观和道德观。 展开更多
关键词 ASSURE模型 大学英语 课程思政 教学模式
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Non-invasive home ventilation using the average volume assured pressure support feature in an infant with severe bronchopulmonary dysplasia and chronic respiratory failure 被引量:1
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作者 Vishal Saddi Ganesh Thambipillay Arthur Teng 《Pediatric Investigation》 CSCD 2020年第3期222-224,共3页
Introduction:While majority of infants with bronchopulmonary dysplasia(BPD)can be discharged home without low flow oxygen or on supplemental low flow oxygen,some require long term home mechanical ventilation.Case pres... Introduction:While majority of infants with bronchopulmonary dysplasia(BPD)can be discharged home without low flow oxygen or on supplemental low flow oxygen,some require long term home mechanical ventilation.Case presentation:We present a case of an extremely premature infant with severe bronchopulmonary dysplasia who was successfully managed at home on a new feature of non-invasive ventilation called average volume assured pressure support(AVAPS)without the need for tracheostomy.The AVAPS feature enables the machine to deliver a consistent tidal volume by automatically adjusting the inspiratory pressure within a set range.Conclusion:The use of AVAPS feature in our case improved ventilation as indicated by a more stable gas exchange profile,making home non-invasive ventilation a more practicable method of managing severe BPD in this infant. 展开更多
关键词 BRONCHOPULMONARY dysplasia HOME ventilation INFANT AVERAGE VOLUME assured PRESSURE support (AVAPS)
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Petroleum exploration and production in Brazil:From onshore to ultra-deepwaters
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作者 ANJOS Sylvia M C SOMBRA Cristiano L SPADINI Adali R 《Petroleum Exploration and Development》 SCIE 2024年第4期912-924,共13页
The Santos Basin in Brazil has witnessed significant oil and gas discoveries in deepwater pre-salt since the 21^(st)century.Currently,the waters in eastern Brazil stand out as a hot area of deepwater exploration and p... The Santos Basin in Brazil has witnessed significant oil and gas discoveries in deepwater pre-salt since the 21^(st)century.Currently,the waters in eastern Brazil stand out as a hot area of deepwater exploration and production worldwide.Based on a review of the petroleum exploration and production history in Brazil,the challenges,researches and practices,strategic transformation,significant breakthroughs,and key theories and technologies for exploration from onshore to offshore and from shallow waters to deep-ultra-deep waters and then to pre-salt strata are systematically elaborated.Within 15 years since its establishment in 1953,Petrobras explored onshore Paleozoic cratonic and marginal rift basins,and obtained some small to medium petroleum discoveries in fault-block traps.In the 1970s,Petrobras developed seismic exploration technologies and several hydrocarbon accumulation models,for example,turbidite sandstones,allowing important discoveries in shallow waters,e.g.the Namorado Field and Enchova fields.Guided by these models/technologies,significant discoveries,e.g.the Marlim and Roncador fields,were made in deepwater post-salt in the Campos Basin.In the early 21^(st)century,the advancements in theories and technologies for pre-salt petroleum system,carbonate reservoirs,hydrocarbon accumulation and nuclear magnetic resonance(NMR)logging stimulated a succession of valuable discoveries in the Lower Cretaceous lacustrine carbonates in the Santos Basin,including the world-class ultra-deepwater super giant fields such as Tupi(Lula),Mero and Buzios.Petroleum development in complex deep water environments is extremely challenging.By establishing the Technological Capacitation Program in Deep Waters(PROCAP),Petrobras developed and implemented key technologies including managed pressure drilling(MPD)with narrow pressure window,pressurized mud cap drilling(PMCD),multi-stage intelligent completion,development with Floating Production Storage and Offloading units(FPSO),and flow assurance,which remarkably improved the drilling,completion,field development and transportation efficiency and safety.Additionally,under the limited FPSO capacity,Petrobras promoted the world-largest CCUS-EOR project,which contributed effectively to the reduction of greenhouse gas emissions and the enhancement of oil recovery.Development and application of these technologies provide valuable reference for deep and ultra-deepwater petroleum exploration and production worldwide.The petroleum exploration in Brazil will consistently focus on ultra-deep water pre-salt carbonates and post-salt turbidites,and seek new opportunities in Paleozoic gas.Technical innovation and strategic cooperation will be held to promote the sustainable development of Brazil's oil and gas industry. 展开更多
关键词 Brazil deepwater pre-salt exploration Campos Basin Santos Basin turbidite sandstone lacustrine carbonate deepwater development flow assurance
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Big data challenge for monitoring quality in higher education institutions using business intelligence dashboards
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作者 Ali Sorour Anthony S.Atkins 《Journal of Electronic Science and Technology》 EI CAS CSCD 2024年第1期25-41,共17页
As big data becomes an apparent challenge to handle when building a business intelligence(BI)system,there is a motivation to handle this challenging issue in higher education institutions(HEIs).Monitoring quality in H... As big data becomes an apparent challenge to handle when building a business intelligence(BI)system,there is a motivation to handle this challenging issue in higher education institutions(HEIs).Monitoring quality in HEIs encompasses handling huge amounts of data coming from different sources.This paper reviews big data and analyses the cases from the literature regarding quality assurance(QA)in HEIs.It also outlines a framework that can address the big data challenge in HEIs to handle QA monitoring using BI dashboards and a prototype dashboard is presented in this paper.The dashboard was developed using a utilisation tool to monitor QA in HEIs to provide visual representations of big data.The prototype dashboard enables stakeholders to monitor compliance with QA standards while addressing the big data challenge associated with the substantial volume of data managed by HEIs’QA systems.This paper also outlines how the developed system integrates big data from social media into the monitoring dashboard. 展开更多
关键词 Big data Business intelligence(BI) Dashboards Higher education(HE) Quality assurance(QA) Social media
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Size-dependent thermomechanical vibration characteristics of rotating pre-twisted functionally graded shear deformable microbeams
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作者 Songye JIN Bo ZHANG +4 位作者 Wuyuan ZHANG Yuxing WANG Huoming SHEN Jing WANG Juan LIU 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2024年第6期1015-1032,共18页
A three-dimensional(3D)thermomechanical vibration model is developed for rotating pre-twisted functionally graded(FG)microbeams according to the refined shear deformation theory(RSDT)and the modified couple stress the... A three-dimensional(3D)thermomechanical vibration model is developed for rotating pre-twisted functionally graded(FG)microbeams according to the refined shear deformation theory(RSDT)and the modified couple stress theory(MCST).The material properties are assumed to follow a power-law distribution along the chordwise direction.The model introduces one axial stretching variable and four transverse deflection variables including two pure bending components and two pure shear ones.The complex modal analysis and assumed mode methods are used to solve the governing equations of motion under different boundary conditions(BCs).Several examples are presented to verify the effectiveness of the developed model.By coupling the slenderness ratio,gradient index,rotation speed,and size effect with the pre-twisted angle,the effects of these factors on the thermomechanical vibration of the microbeam with different BCs are investigated.It is found that with the increase in the pre-twisted angle,the critical slenderness ratio and gradient index corresponding to the thermal instability of the microbeam increase,while the critical material length scale parameter(MLSP)and rotation speed decrease.The sensitivity of the fundamental frequency to temperature increases with the increasing slenderness ratio and gradient index,and decreases with the other increasing parameters.Moreover,the size effect can suppress the dynamic stiffening effect and enhance the Coriolis effect.Finally,the mode transition is quantitatively demonstrated by a modal assurance criterion(MAC). 展开更多
关键词 thermomechanical vibration rotating pre-twisted functionally graded(FG)microbeam refined shear deformation theory(RSDT) modified couple stress theory(MCST) modal assurance criterion(MAC)
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ISO/TC 321电子商务标准化工作对非洲发展中国家的启示
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作者 Liberty Artwell Mareya 宋明顺 吴宏宽 《China Standardization》 2024年第2期73-76,共4页
This paper draws on the experience of the eighth plenary meeting of the ISO/TC 321, Transaction assurance in e-commerce, held in Hangzhou of China in November 2023, and explores potential ways in which developing coun... This paper draws on the experience of the eighth plenary meeting of the ISO/TC 321, Transaction assurance in e-commerce, held in Hangzhou of China in November 2023, and explores potential ways in which developing countries in Africa can drive their development and contribute to global industrial progress by leveraging ISO/TC 321 standards. It provides practical recommendations for utilizing e-commerce standardization and related standards to stimulate economic growth and enhance business practices. 展开更多
关键词 ISO/TC 321 E-COMMERCE transaction assurance China developing countries AFRICA
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Flexible pavement longitudinal joint quality evaluation using non-destructive testing
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作者 Hamad Bin Muslim Syed Waqar Haider Lev Khazanovich 《Journal of Road Engineering》 2024年第2期189-202,共14页
Longitudinal joint construction quality is critical to the life of flexible pavements.Maintaining deteriorated longitudinal joints has become a challenge for many highway agencies.Improving the joint's quality thr... Longitudinal joint construction quality is critical to the life of flexible pavements.Maintaining deteriorated longitudinal joints has become a challenge for many highway agencies.Improving the joint's quality through better compaction during construction can help achieve flexible pavements with longer service lives and less maintenance.Current quality control(QC)and quality assurance(QA)plans provide limited coverage.Consequently,the risk of missing areas with poor joint compaction is significant.A density profiling system(DPS)is a non-destructive alternative to conventional destructive evaluation methods.It can provide quick and continuous real-time coverage of the compaction during construction in dielectrics.The paper presents several case studies comparing various types of longitudinal joints and demonstrating the use of DPS to evaluate the joint's compaction quality.The paper shows that dielectric measurements can provide valuable insight into the ability of various construction techniques to achieve adequate levels of compaction at the longitudinal joint.The paper proposes a dielectric-based longitudinal joint quality index(LJQI)to evaluate the relative compaction of the joint during construction.It also shows that adopting DPS for assessing the compaction of longitudinal joints can minimize the risk of agencies accepting poorly constructed joints,identify locations of poor quality during construction,and achieve better-performing flexible pavements. 展开更多
关键词 Sustainable pavements Dielectric/density profiling system Quality assurance Non-destructive testing Asphalt longitudinal joint
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ASSURE模式在提升手术室新护士手术配合准备度中的应用
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作者 李跃萍 宋辉 +1 位作者 王新月 苏佳杰 《天津护理》 2024年第3期330-334,共5页
目的:探讨ASSURE模式在手术室新护士手术配合准备度教学培训中的应用效果。方法:将2019年1月至2020年12月入职的21名手术室新护士纳入对照组,2021年1月至2023年3月入职的29名手术室新护士纳入观察组。对照组采用传统的教学模式,观察组采... 目的:探讨ASSURE模式在手术室新护士手术配合准备度教学培训中的应用效果。方法:将2019年1月至2020年12月入职的21名手术室新护士纳入对照组,2021年1月至2023年3月入职的29名手术室新护士纳入观察组。对照组采用传统的教学模式,观察组采用ASSURE模式。培训时间为3个月。比较两组新护士培训后的理论与操作考核成绩、手术配合能力认可度得分、手术配合准备度得分、教学满意度评分。结果:观察组理论与操作考核成绩、手术配合能力认可度、手术配合准备度得分及教学满意度评分均高于对照组,差异均有统计学意义(P<0.05)。结论:ASSURE模式可提高手术室新护士理论知识及操作技能,提升外科医生对手术室新护士手术配合能力的认可度、提升手术室新护士手术配合准备度自我评价及对教学的满意度。 展开更多
关键词 ASSURE模式 手术室 新护士 手术配合 准备度
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A Study on the Challenges of Human-Centric Cyber-Security and the Guarantee of Information Quality
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作者 Mohammed Hussein Kurdi Mohsen Denden David Paul 《Journal of Information Security》 2024年第2期218-231,共14页
Information security and quality management are often considered two different fields. However, organizations must be mindful of how software security may affect quality control. This paper examines and promotes metho... Information security and quality management are often considered two different fields. However, organizations must be mindful of how software security may affect quality control. This paper examines and promotes methods through which secure software development processes can be integrated into the Systems Software Development Life-cycle (SDLC) to improve system quality. Cyber-security and quality assurance are both involved in reducing risk. Software security teams work to reduce security risks, whereas quality assurance teams work to decrease risks to quality. There is a need for clear standards, frameworks, processes, and procedures to be followed by organizations to ensure high-level quality while reducing security risks. This research uses a survey of industry professionals to help identify best practices for developing software with fewer defects from the early stages of the SDLC to improve both the quality and security of software. Results show that there is a need for better security awareness among all members of software development teams. 展开更多
关键词 Cyber Security Development Methodology Information Quality Human-Centric SDLC Quality Assurance
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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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Comparative Study of Evaluation Indicators for Learning Cities and the Implications
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作者 Chi Xu 《Journal of Contemporary Educational Research》 2024年第10期279-286,共8页
With the development of society,more and more cities are participating in the initiative to build learning cities.Constructing an evaluation indicator system for learning cities to monitor the progress and promote the... With the development of society,more and more cities are participating in the initiative to build learning cities.Constructing an evaluation indicator system for learning cities to monitor the progress and promote their growth has become increasingly important.This paper analyzes the preliminary framework of the UNESCO Global Learning City Index and R3L+Quality Framework.The comparison is made from the aspects of design philosophy,criteria of indicator,and the cycle of evaluation process.The findings suggest that the construction of an evaluation indicator system should be focused more on the diversity of learning city development,the construction of an evaluation process cycle,and the significance of building cooperative networks. 展开更多
关键词 Learning city United Nations Evaluation indicator system Quality assurance framework
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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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Construction Method of Civil Aircraft Airborne⁃system Supplier Development Process System
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作者 PU Youhua LI Lin LI Li 《International Journal of Plant Engineering and Management》 2024年第2期65-77,共13页
Based on the analysis of the development process system status of domestic and foreign civil aircraft airborne system suppliers,this paper proposes the overall construction idea of"a set of civil aircraft process... Based on the analysis of the development process system status of domestic and foreign civil aircraft airborne system suppliers,this paper proposes the overall construction idea of"a set of civil aircraft process system"based on IPD(Integrated product development)in the organization.The development stage,process,activity and task are the logical framework elements of the system construction."Based on process decomposition,vertical stratification,horizontal segmentation,combination of special and common,process customized to tools,role and process integration,giving full consideration to the interface between supplier management and process modules"etc.are the concrete ideas.Moreover,formulate top⁃level system construction standards,implemented by process system management tool platform,so that the process system and development work can be effectively integrated to effectively guide the development work of airborne system suppliers,and meet the quality and airworthiness requirements of civil aircraft development.Through the development application of a certain type of flight control system,the process system and tool platform were verified and optimized in practice. 展开更多
关键词 development process system development assurance process integrated product development(IPD) development stage ACTIVITY
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Hydrate Prevention Strategies and the Associated Cost in the Gulf of Mexico
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作者 Ibrahim Ninalowo Bahman Tohidi 《World Journal of Engineering and Technology》 2024年第2期286-309,共24页
With the petroleum industry endeavoring to develop promising oil and gas in deeper water, gas hydrates prevention is a serious concern for oil and gas producing companies producing at conditions in the hydrate region.... With the petroleum industry endeavoring to develop promising oil and gas in deeper water, gas hydrates prevention is a serious concern for oil and gas producing companies producing at conditions in the hydrate region. This paper details lessons learned from the successful field deployment of AA LDHI and proper implementation strategies used for 3 different practical fields as case studies in the Gulf of Mexico. From the 3 field experiences, the AA LDHI has been used to replace the conventional thermodynamic hydrate inhibitor due to its numerous benefits during steady state operations and transition operations where AA LDHI is injected prior to extended shut in and restart for fields producing at low water cut. However, the strategy to develop a cost effective chemical management of hydrates for fields producing at high water cut is by pumping methanol or diesel to push down the wellbore fluid below the mud line during planned and unplanned shut-ins to delay water production, it also secures the riser with non hydrate fluids. This illustrates how the AA LDHIs are used in conjunction with more conventional hydrate management approaches to reach an optimal cost effective field hydrate management solution. However, this shows that the key to overall success of hydrate prevention is a full integration of a good front end design, a comprehensive deployment and an effective down hole monitoring system. 展开更多
关键词 Flow Assurance Hydrate Production Chemistry Hydrate Inhibitor Hydrate Prevention Strategies Deep Water Oil and Gas Production Hydrate Blockage
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Numerical modeling and parametric sensitivity analysis of heat transfer and two-phase oil and water flow characteristics in horizontal and inclined flowlines using OpenFOAM 被引量:1
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作者 Nsidibe Sunday Abdelhakim Settar +1 位作者 Khaled Chetehouna Nicolas Gascoin 《Petroleum Science》 SCIE EI CAS CSCD 2023年第2期1183-1199,共17页
Estimating the oil-water temperatures in flowlines is challenging especially in deepwater and ultra-deepwater offshore applications where issues of flow assurance and dramatic heat transfer are likely to occur due to ... Estimating the oil-water temperatures in flowlines is challenging especially in deepwater and ultra-deepwater offshore applications where issues of flow assurance and dramatic heat transfer are likely to occur due to the temperature difference between the fluids and the surroundings. Heat transfer analysis is very important for the prediction and prevention of deposits in oil and water flowlines, which could impede the flow and give rise to huge financial losses. Therefore, a 3D mathematical model of oil-water Newtonian flow under non-isothermal conditions is established to explore the complex mechanisms of the two-phase oil-water transportation and heat transfer in different flowline inclinations. In this work, a non-isothermal two-phase flow model is first modified and then implemented in the InterFoam solver by introducing the energy equation using OpenFOAM® code. The Low Reynolds Number (LRN) k-ε turbulence model is utilized to resolve the turbulence phenomena within the oil and water mixtures. The flow patterns and the local heat transfer coefficients (HTC) for two-phase oil-water flow at different flowlines inclinations (0°, +4°, +7°) are validated by the experimental literature results and the relative errors are also compared. Global sensitivity analysis is then conducted to determine the effect of the different parameters on the performance of the produced two-phase hydrocarbon systems for effective subsea fluid transportation. Thereafter, HTC and flow patterns for oil-water flows at downward inclinations of 4°, and 7° can be predicted by the models. The velocity distribution, pressure gradient, liquid holdup, and temperature variation at the flowline cross-sections are simulated and analyzed in detail. Consequently, the numerical model can be generally applied to compute the global properties of the fluid and other operating parameters that are beneficial in the management of two-phase oil-water transportation. 展开更多
关键词 Flow assurance Flow pattern Heat transfer Flowlines Two-phase flow Global sensitivity analysis
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