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Role based access control design using Triadic concept analysis 被引量:9
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作者 Ch.Aswani Kumar S.Chandra Mouliswaran +1 位作者 LI Jin-hai C.Chandrasekar 《Journal of Central South University》 SCIE EI CAS CSCD 2016年第12期3183-3191,共9页
Role based access control is one of the widely used access control models.There are investigations in the literature that use knowledge representation mechanisms such as formal concept analysis(FCA),description logics... Role based access control is one of the widely used access control models.There are investigations in the literature that use knowledge representation mechanisms such as formal concept analysis(FCA),description logics,and Ontology for representing access control mechanism.However,while using FCA,investigations reported in the literature so far work on the logic that transforms the three dimensional access control matrix into dyadic formal contexts.This transformation is mainly to derive the formal concepts,lattice structure and implications to represent role hierarchy and constraints of RBAC.In this work,we propose a methodology that models RBAC using triadic FCA without transforming the triadic access control matrix into dyadic formal contexts.Our discussion is on two lines of inquiry.We present how triadic FCA can provide a suitable representation of RBAC policy and we demonstrate how this representation follows role hierarchy and constraints of RBAC on sample healthcare network available in the literature. 展开更多
关键词 access control concept lattice role based access control role hierarchy triadic context triadic concept analysis
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Permission and role automatic assigning of user in role-based access control 被引量:4
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作者 韩道军 卓汉逵 +1 位作者 夏兰亭 李磊 《Journal of Central South University》 SCIE EI CAS 2012年第4期1049-1056,共8页
Role mining and setup affect the usage of role-based access control(RBAC).Traditionally,user's role and permission assigning are manipulated by security administrator of system.However,the cost is expensive and th... Role mining and setup affect the usage of role-based access control(RBAC).Traditionally,user's role and permission assigning are manipulated by security administrator of system.However,the cost is expensive and the operating process is complex.A new role analyzing method was proposed by generating mappings and using them to provide recommendation for systems.The relation among sets of permissions,roles and users was explored by generating mappings,and the relation between sets of users and attributes was analyzed by means of the concept lattice model,generating a critical mapping between the attribute and permission sets,and making the meaning of the role natural and operational.Thus,a role is determined by permission set and user's attributes.The generated mappings were used to automatically assign permissions and roles to new users.Experimental results show that the proposed algorithm is effective and efficient. 展开更多
关键词 role-based access control role permission assignment concept lattice
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应用AOP技术实现Role Object模式
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作者 李伟斋 应时 叶钰 《计算机应用》 CSCD 北大核心 2005年第5期1061-1063,共3页
RoleObject模式是用于实现角色模型的最通用的设计模式。但面向对象的RoleObject模式实现方案中,存在着混合与散乱、复杂对象同一性及向下转型或接口膨胀等一些固有缺陷。基于AOP技术,提出了一种称为“混合方法”的实现RoleObject模式... RoleObject模式是用于实现角色模型的最通用的设计模式。但面向对象的RoleObject模式实现方案中,存在着混合与散乱、复杂对象同一性及向下转型或接口膨胀等一些固有缺陷。基于AOP技术,提出了一种称为“混合方法”的实现RoleObject模式的方案,并通过与面向对象实现方案的比较,得出了AOP技术实现方案具有模块松散耦合、可重用性高等优点的结论。 展开更多
关键词 AOP role OBJECT 设计模式
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RoleTracker:基于角色的社会网络演化分析方法 被引量:3
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作者 段松青 于兴隆 +1 位作者 吴斌 王柏 《湖南大学学报(自然科学版)》 EI CAS CSCD 北大核心 2015年第8期132-140,共9页
已有的用户角色研究中,不少学者定义了角色的数目和特征,对特定数据集取得了较好的效果,但存在的两个问题:1)通用性较差,若更换数据集必须重新分析;2)现实世界中用户行为和关系纷繁复杂,用户角色多种多样,难以通过人为的定义去描述和识... 已有的用户角色研究中,不少学者定义了角色的数目和特征,对特定数据集取得了较好的效果,但存在的两个问题:1)通用性较差,若更换数据集必须重新分析;2)现实世界中用户行为和关系纷繁复杂,用户角色多种多样,难以通过人为的定义去描述和识别.因此,本文基于张量分解模型提出了一种用户角色发现算法,它不仅能自动设定角色数量,而且能反映角色在指定时间段的行为特征.进一步将用户角色延伸到社团角色,提出基于社团角色距离和节点重叠的社团演化分析方法.实验结果表明,识别出的用户角色其行为特征与实际情况吻合,提出的社团演化分析方法其效果也高于对比算法. 展开更多
关键词 社会网络 角色发现 张量 社团演化
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College English Teachers' Roles in CAI
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作者 郭艳 董俊虹 《陕西师范大学学报(哲学社会科学版)》 CSSCI 北大核心 2004年第S2期412-414,共3页
With continuing advances in technology, computer-assisted instruction provides opportunities for individualized, interactive instruction. The philosophy of constructivism has encouraged instructional designers to crea... With continuing advances in technology, computer-assisted instruction provides opportunities for individualized, interactive instruction. The philosophy of constructivism has encouraged instructional designers to create less behavioral, more democratic programs that promote learner control. In the area of ESL (English as a second language), computers are seen to be a highly motivating, instructional tool. 展开更多
关键词 CAI LANGUAGE teaching teachers’ roleS MOTIVATION
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Ensemble feature selection integrating elitist roles and quantum game model 被引量:1
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作者 Weiping Ding Jiandong Wang +1 位作者 Zhijin Guan Quan Shi 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2015年第3期584-594,共11页
To accelerate the selection process of feature subsets in the rough set theory (RST), an ensemble elitist roles based quantum game (EERQG) algorithm is proposed for feature selec- tion. Firstly, the multilevel eli... To accelerate the selection process of feature subsets in the rough set theory (RST), an ensemble elitist roles based quantum game (EERQG) algorithm is proposed for feature selec- tion. Firstly, the multilevel elitist roles based dynamics equilibrium strategy is established, and both immigration and emigration of elitists are able to be self-adaptive to balance between exploration and exploitation for feature selection. Secondly, the utility matrix of trust margins is introduced to the model of multilevel elitist roles to enhance various elitist roles' performance of searching the optimal feature subsets, and the win-win utility solutions for feature selec- tion can be attained. Meanwhile, a novel ensemble quantum game strategy is designed as an intriguing exhibiting structure to perfect the dynamics equilibrium of multilevel elitist roles. Finally, the en- semble manner of multilevel elitist roles is employed to achieve the global minimal feature subset, which will greatly improve the fea- sibility and effectiveness. Experiment results show the proposed EERQG algorithm has superiority compared to the existing feature selection algorithms. 展开更多
关键词 ensemble quantum game utility matrix of trust mar-gin dynamics equilibrium strategy multilevel elitist role feature selection and classification.
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The Role of Ground Water in Malawi
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作者 Sophie Wongani Matete 《地学前缘》 EI CAS CSCD 北大核心 2009年第S1期9-9,共1页
Research has shown that groundwater plays a very great role in Malawi.It has been revealed that many people who live in rural areas in Malawi depend on groundwater for drinking and other domestic uses. According to re... Research has shown that groundwater plays a very great role in Malawi.It has been revealed that many people who live in rural areas in Malawi depend on groundwater for drinking and other domestic uses. According to research which was conducted in Malawi using focus group discussion,observations and other data sources collected from other 展开更多
关键词 role management POLLUTION ENVIRONMENT RURAL POOR PEOPLE
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Roles for α_Vβ_3 and GP Ilb/Illa integrins in MDA-MB-231cell invasion and shear flow-induced mechanotransduction
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作者 Fenglong Zhao Li Li +3 位作者 Liuyuan Guang Hong Yang Chunhui Wu Yiyao Liu 《医用生物力学》 EI CAS CSCD 北大核心 2013年第S1期51-52,共2页
Introduction Hematogenous metastasis is the mainly leading cause of death in breast carcinoma patients.A better understanding of the underlying molecular and cellular mechanisms is crucial for the development of effec... Introduction Hematogenous metastasis is the mainly leading cause of death in breast carcinoma patients.A better understanding of the underlying molecular and cellular mechanisms is crucial for the development of effective treatment for metastatic breast cancer<sup>[</sup>1].It has been well established that cell adhesion and invasion is mediated by a variety of transmembrane proteins,including integrins,cadherins,selectins,and intercellular adhesion molecules.Among these adhesion molecules,the integrins and their downstream signaling pathways have been extensively studied<sup>[2]</sup>.On the other hand,the specific events determining tumor cell interactions with endo- 展开更多
关键词 invasion roleS for metastatic metastasis INTERCELLULAR downstream signaling underlying integrin TRANSMEMBRANE
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The Kinematic Team Role Behavior in Work Team
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作者 Samuel H N Leung Joseph W K Chan W B Lee 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 2002年第S1期262-,共1页
Work-team has emerged as an important unit composi ng the organization today. The concepts relating to the properties of team-role t hat fit with today’s business environment have attracted much attention from the th... Work-team has emerged as an important unit composi ng the organization today. The concepts relating to the properties of team-role t hat fit with today’s business environment have attracted much attention from the theorists and researchers. A team having a balanced composition of team-ro les is called a balanced team. Theoretically, a balanced team usually renders a better team performance. Therefore, to improve the performance of the team, mana gement needs to ensure that their work teams are composed of appropriate team me mbers with complementary skills, playing different roles, together forming a bal anced team. However, in certain situation, a balanced team can hardly be formed. For example , companies in Hong Kong are mostly the small-to-medium sized enterprises. The number of team-members is usually smaller than the required number for formula ting a balanced team. Also, as team members are required to travel often across borders, stable team can hardly be maintained. To resolve this problem, a different paradigm of team-role prevails here. Team -members autonomously supplant the roles of those missing members. We call this phenomenon the kinetic team role behavior. By using the methodology adopted from psychotherapy study, we propose a way to investigate this interesting and important characteristics of team-role. 展开更多
关键词 The Kinematic Team role Behavior in Work Team WORK
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The role of TIPS in the management of portal hypertension:a new perspective
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作者 Douglas M.Coldwell 《介入放射学杂志》 CSCD 2006年第12期767-767,768,共2页
Introduction The Transjugular Intra-hepatic Porto-Systemic Shunt(TIPS)was introduced in the early 1990's by Josef Rosch.It rapidly gained popularity in the US where at that time we were performing many per week.Or... Introduction The Transjugular Intra-hepatic Porto-Systemic Shunt(TIPS)was introduced in the early 1990's by Josef Rosch.It rapidly gained popularity in the US where at that time we were performing many per week.Originally,it was utilized to treat variceal hemorrhage with good results but,over time, endoscopic banding procedures have become better and the shunt has fallen into relative disfavor due to its higher than expected closure rate.In the ensuing fifteen years,there have been many changes in the approach to the treatment of portal hypertension and more specific role for this specialized procedure. 展开更多
关键词 TIPS The role of TIPS in the management of portal hypertension
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Role of Information Technology in Manufacturing
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作者 Shankar Singh A V Muley 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 2002年第S1期256-,共1页
Manufacturing of a product is constituted of the va ri ous attributes such as quality, cost, performance, and time to market. Manufactu ring can also be understood as the entire product realization process, from spec ... Manufacturing of a product is constituted of the va ri ous attributes such as quality, cost, performance, and time to market. Manufactu ring can also be understood as the entire product realization process, from spec ification through design and production to marketing and distribution. The induc tion of Information Technology (IT) in manufacturing includes the hardware that computes and communicates, the software that provides data, knowledge, and infor mation while at the same time controlling the hardware, and the interfaces betwe en computers and the tools and machines on the shop floor. The manufacturing pro cess utilizes IT in the design of products and processes, production, and manufa cturing-related business practices. IT applications applied to manufacturing helps in rapid shifts in production fro m one product to another, faster implementation of new concepts in products, fas ter delivery of products to customers, full utilization of capital and human res ources, streamlining of operations to focus on essential business needs, and eli mination of unnecessary or wasteful activities. IT can be used to meet a range of needs of manufacturing decision makers. It can be said that IT is an enabler and facilitator of radical change to culture of manufacturing which is highly co nservative for many good reasons. With increasing global competition, applications of global information technolog y is giving manufacturing unit an opportunity to increase control and enhance co ordination, while opening doors to new global markets and businesses. In some st udies conducted it ahs been shown that how information technology can produce pr oductivity gains and job losses in specific areas, whereas dynamic stability was also achieved through IT in some cases. In a study of an industry the IT has cu t manufacturers cost from eProcurement to web based supply chain management and after sales service. IT has certainly revolutionized the manufacturing and the i ndustries have completely redefined their business by switching over to World Wi de Web. This paper, attempts to review the significant advances and practical applicatio ns of information technology in the field of manufacturing. 展开更多
关键词 role of Information Technology in Manufacturing
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The Role and the Function of Japan Institute of Sports Sciences and National Training Center in Japan
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作者 Kazuya Kasahara 《中国体育科技》 CSSCI 北大核心 2009年第1期30-32,共3页
Gold Medals in Summer Qlympics Measures A 1) Program to develop junior athletes to top level 2) National Training Center 3) National Coach Academy B 1) Sports medicine and sciences(JISS) 2) Anti-doping 3) To hold inte... Gold Medals in Summer Qlympics Measures A 1) Program to develop junior athletes to top level 2) National Training Center 3) National Coach Academy B 1) Sports medicine and sciences(JISS) 2) Anti-doping 3) To hold international 展开更多
关键词 The role and the Function of Japan Institute of Sports Sciences and National Training Center in Japan
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Understanding China and Its Role in the World
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作者 Tony Blair 《国际展望》 2010年第5期62-75,共14页
Mr. President, Ambassador, everyone, ladies and gentlemen,it is a great pleasure to be with you here at Shanghai Institutes for International Studies. Thank you, Mr. President for
关键词 Understanding China and Its role in the World very
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Role-based Context-specific Multiagent Q-learning 被引量:1
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作者 JIANG Da-Wei WANG Shi-Yuan DONG Yi-Sheng 《自动化学报》 EI CSCD 北大核心 2007年第6期583-587,共5页
在合作multiagent学习的主要问题之一是联合行动空间与代理人的数字指数地成长。在这份报纸,我们调查在代理人之间的协作相关性的一个稀少的代表采用角色和上下文特定的协作图减少联合行动空间。在我们的框架,全球联合Q功能被分解成很... 在合作multiagent学习的主要问题之一是联合行动空间与代理人的数字指数地成长。在这份报纸,我们调查在代理人之间的协作相关性的一个稀少的代表采用角色和上下文特定的协作图减少联合行动空间。在我们的框架,全球联合Q功能被分解成很多本地Q功能。各本地的Q功能在代理人的一个小组之中被分享并且由一套价值规则组成。我们建议自动地在每条价值规则学习重量的一个新奇multiagent学习Q算法。我们给实验证据证明我们的学习算法比学习技术的传统的multiagent以显著地更快的速度收敛到一样的最佳的政策。 展开更多
关键词 多主体合作 Q函数 角色 算法 特定合作曲线图 自动化
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The Issue of Self-concept:Perceptions of Chinese Student Teachers about Their Roles
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作者 Li Hui 《学术界》 CSSCI 北大核心 2013年第6期262-268,共7页
This article has presented some stereotypical views held by Western people about Chinese teachers,and then clarified these misperceptions caused by Western people's different understanding of the meanings of "... This article has presented some stereotypical views held by Western people about Chinese teachers,and then clarified these misperceptions caused by Western people's different understanding of the meanings of "teacher authority","double parental identities",and"strictness"compared to their Chinese counterparts.Then a case study of three Chinese student teachers studying in one Australian university is conducted to analyze their feelings and experiences of teaching in Australia.Finally,the study suggests that Chinese teacher must retain the essence of Chinese good teachers while adopting the advantages of Western teaching culture to improve his / her own teaching practice,and if so,these self changes could be significant to recreate themselves as new Chinese teachers. 展开更多
关键词 新中国 教师 学生 发行 澳大利亚 教学经验 教学文化 教学实践
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强化企业主体地位推进建设制造强国
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作者 钟志华 黄庆学 +4 位作者 朱明皓 邵立国 臧冀原 焦伊景 路守望 《中国工程科学》 北大核心 2026年第1期106-116,共11页
企业是市场经济的和科技创新的主体、推动制造业高质量发展的关键载体,先进制造业集群是企业集聚和协同发展的产业生态系统,强化企业主体地位、培育世界级先进制造业集群是推进制造强国建设的关键支撑。本文从龙头企业、中小企业、先进... 企业是市场经济的和科技创新的主体、推动制造业高质量发展的关键载体,先进制造业集群是企业集聚和协同发展的产业生态系统,强化企业主体地位、培育世界级先进制造业集群是推进制造强国建设的关键支撑。本文从龙头企业、中小企业、先进制造业集群3个层面出发,对以企业为主体推进制造强国建设的主要成就进行了系统梳理与分析,并讨论了领军企业、中小企业和世界级先进制造业集群的发展重点任务。在制造强国建设进程中,企业体系整体实力持续提升:制造业龙头企业规模实力、国际市场竞争力显著提升,在关键核心技术攻关、产业链组织中发挥了引领作用;中小企业梯度培育体系逐步完善,以专精特新“小巨人”、制造业“单项冠军”为代表的中小企业在细分领域和关键环节的专业化能力明显增强;国家先进制造业集群、中小企业特色产业集群加快布局,成为承载制造业高质量发展的重要空间载体。面向未来,应集中要素资源支持企业主体能力建设,培育具有国际产业链控制力的领军企业,推动大中小企业融通发展,加快中小企业数字化转型和“人工智能+”应用场景培育,持续提升国家先进制造业集群竞争力,为制造强国建设筑牢坚实的微观基础和中观支撑。 展开更多
关键词 制造强国 主体地位 领军企业 中小企业 先进制造业集群 产业链协同
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协同治理视角下的研究生教育内部质量治理主体权力与角色分析
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作者 肖敏 付雪琳 徐含乐 《研究生教育研究》 北大核心 2026年第1期93-102,共10页
基于协同治理视角,聚焦研究生教育内部质量治理的核心,运用社会网络分析方法对招生、培养、学位授予等关键事务中治理主体的权力分配与角色定位进行实证研究。研究发现,研究生教育内部质量治理主体权力分配具有权力高度集中于单一行政主... 基于协同治理视角,聚焦研究生教育内部质量治理的核心,运用社会网络分析方法对招生、培养、学位授予等关键事务中治理主体的权力分配与角色定位进行实证研究。研究发现,研究生教育内部质量治理主体权力分配具有权力高度集中于单一行政主体;权力相对分散但行政主体仍占主导;权力分配较为均衡,学术主体影响力上升;权力重心转向政治主体,行政主体权力相对减弱等不同特征。同时,治理主体角色也因决策事件不同而不同,其中行政主体、学术主体、政治主体以及研究生这一民主主体多为核心决策者与协调者,其余治理主体多为资源依赖者、被动参与者、孤立者。总体来看,研究生教育内部质量治理呈现出多样化的权力结构类型,包括行政主导型、行政—学术协同型、政治主导型以及多元分散型等。为优化研究生教育内部治理格局,提出构建“分层协同治理”模式,强化“网络化治理”机制,完善“制度保障体系”等建议。 展开更多
关键词 研究生教育内部质量 质量治理 权力分配 角色分析
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正发党时期土耳其国家角色重构与海外利益拓展
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作者 贺文萍 刘姝含 《阿拉伯世界研究》 北大核心 2026年第2期76-97,158,共23页
土耳其海外利益的拓展轨迹与其对自身角色定位的转变同步发展。自建国以来,土耳其共和国国家角色的迭代直接驱动其海外利益从建国初期的尚未显现,转向冷战期间的有限发展,再到后冷战时期的战略过渡,最终在正义与发展党任期内完成爆发式... 土耳其海外利益的拓展轨迹与其对自身角色定位的转变同步发展。自建国以来,土耳其共和国国家角色的迭代直接驱动其海外利益从建国初期的尚未显现,转向冷战期间的有限发展,再到后冷战时期的战略过渡,最终在正义与发展党任期内完成爆发式增长的阶段性演进。如今,在正义与发展党政府所坚持的“全球行动者”角色定位下,土耳其已经转变为拥有全球性海外利益的重要国家,通过安全秩序建构、经济利益扩张、文化共同体塑造三大核心手段,逐步构建起符合自身国情的海外利益拓展模式。该模式具有明显的积极干预倾向并受领导人强势驱动,同时也受制于国内经济承载力不足、国家间博弈等制约因素的影响。目前,土耳其海外利益拓展进程仍在继续,其未来走向也将成为检验新兴市场国家在国际秩序转型期内能否实现可持续性战略突围的关键样本。 展开更多
关键词 土耳其 海外利益 “全球行动者” 国家角色
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基于角色责任的医学伦理素养之培育
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作者 刘俊荣 《医学与哲学》 北大核心 2026年第5期1-6,28,共7页
角色责任针对的是某个人所占据的岗位或位置而非其个人,医者的角色责任有其特殊的内涵和要求。当前的医学伦理教育更重视“三基教育”,而对角色责任关注度不够,这表现在岗位胜任力教育、医文融合、教材体系、教育环境等方面。医者角色... 角色责任针对的是某个人所占据的岗位或位置而非其个人,医者的角色责任有其特殊的内涵和要求。当前的医学伦理教育更重视“三基教育”,而对角色责任关注度不够,这表现在岗位胜任力教育、医文融合、教材体系、教育环境等方面。医者角色责任的强化需要吸收中华优秀传统伦理教育之精华,借鉴西方医学伦理教育之经验,以临床实践中的重点、难点、热点伦理问题为导向,改革教材体系和教育教学内容及方法,构建全员、全程、全方位的育人环境,充分发挥隐性课程的正面导向性作用。 展开更多
关键词 角色责任 医学伦理素养 岗位胜任力
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我国公共体育场馆网络化治理的主体角色定位与权责边界
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作者 陈元欣 刘思思 《沈阳体育学院学报》 北大核心 2026年第1期115-122,共8页
本研究运用文献资料法和逻辑分析法,基于网络化治理理论构建公共体育场馆治理数学模型,科学界定多元主体在公共体育场馆治理中的角色定位与权责边界。研究认为,公共体育场馆治理效益与市场主体的投入水平、权责配置呈“倒U型”关系,与... 本研究运用文献资料法和逻辑分析法,基于网络化治理理论构建公共体育场馆治理数学模型,科学界定多元主体在公共体育场馆治理中的角色定位与权责边界。研究认为,公共体育场馆治理效益与市场主体的投入水平、权责配置呈“倒U型”关系,与政府和社会主体的投入水平呈“伞形”关系。为实现公共体育场馆治理效益最大化的目标,各主体应将其投入水平与权责配置限定在合理有效的区间内。政府主体应由有限政府转向有为政府,市场主体应由辅助力量转向中坚力量,社会主体应由被动参与转向主动担责。通过明确多元主体的角色定位与权责边界,促进其良性互动与合作,探索构建高效协同的“有为政府-有效市场-有机社会”公共体育场馆治理模式,以期为破解多元主体协同困境、强化多元主体协同效能、优化公共体育场馆服务供给模式提供理论支持与实践参考。 展开更多
关键词 公共体育场馆 网络化治理 角色定位 权责边界 多元主体
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