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“云连接论”视角下大学英语学习云共同体框架构建和应用

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黑龙江教育(理论与实践) 2025年第1期 46-48页

作者：金曦武汉城市学院外语学部湖北武汉430008

“云连接论”展示了内外2个圈层的循环。其中,3个相互交叉的假设构成内圈,即“认知连接”“社会连接”“情感连接”,并通过“问题链”相互连接;共同体活动的3个阶段则构成了外圈。该理论可为大学英语学习云共同体框架构建提供理论基础,... 详细信息

“云连接论”展示了内外2个圈层的循环。其中,3个相互交叉的假设构成内圈,即“认知连接”“社会连接”“情感连接”,并通过“问题链”相互连接;共同体活动的3个阶段则构成了外圈。该理论可为大学英语学习云共同体框架构建提供理论基础,而学习云共同体(Cloud Learning Community,CLC)学习小组组织形式可为大学英语教学注入新的活力。文章旨在研究如何将“云连接论”和学习云共同体有机融入大学英语教学中,以实现大学英语课程专业育人和情感育人目标。

关键词： “云连接论” 学习云共同体线上线下 “大学英语”课程改革

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热机械处理提高Cr_(47)Ni_(33)Co_(10)Fe_(10)多组元共晶合金力学性能

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材料导报 2025年第3期39卷 208-213页

作者：薛赞晋玺毛周朱兰爱东王大雨乔珺威太原理工大学材料科学与工程学院太原030024 太原理工大学机械与运载工程学院应用力学研究所太原030024 太原理工大学教育部先进材料界面科学与工程重点实验室太原030024

无序面心立方(FCC)+无序体心立方(BCC)结构多组元共晶合金(MCEA)Cr_(47)Ni_(33)Co_(10)Fe_(10)具有重要的工程应用价值。本工作采用多道次冷轧使合金厚度减少90%并在800℃下退火1 h的热机械处理策略来提高合金力学性能。Cr_(47)Ni_(33)C... 详细信息

无序面心立方(FCC)+无序体心立方(BCC)结构多组元共晶合金(MCEA)Cr_(47)Ni_(33)Co_(10)Fe_(10)具有重要的工程应用价值。本工作采用多道次冷轧使合金厚度减少90%并在800℃下退火1 h的热机械处理策略来提高合金力学性能。Cr_(47)Ni_(33)Co_(10)Fe_(10)合金热机械处理后的屈服强度(σ_(0.2))为1230 MPa,拉伸断裂应变(ε)为13%,屈服强度相对于铸态合金提高了864 MPa,是铸态合金的三倍多,且几乎没有损失塑性。高强度和高塑性的匹配来源于超细双相等轴晶组织替代了初始层片组织。本工作为提高双相共晶高熵合金的力学性能提供了一种可行的热处理工艺途径。

关键词：共晶高熵合金热机械处理超细晶力学性能

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面向核心素养的大学英语互动教学模式探究

科教文汇 2025年第3期 I0006-I0008页

作者：金玺唐建福湖南科技学院外国语学院湖南永州425199

大学英语互动课堂是践行英语核心素养的重要场地。大学英语课堂互动教学以英语核心素养培养为宗旨,以小组讨论、角色扮演、合作学习为途径,以多媒体教学为手段,助力课堂多元互动。在课堂互动教学过程中,教师要尊重学生的主体地位,注重... 详细信息

大学英语互动课堂是践行英语核心素养的重要场地。大学英语课堂互动教学以英语核心素养培养为宗旨,以小组讨论、角色扮演、合作学习为途径,以多媒体教学为手段,助力课堂多元互动。在课堂互动教学过程中,教师要尊重学生的主体地位,注重个体性教学,强化互动与合作,以培养学生思维品质为目的;开展文化主题讨论,通过角色扮演与情景模拟,提高学生的语言能力;通过自主学习,提高学生的问题解决能力。

关键词：核心素养大学英语互动教学模式

A Method of Estimating Computational Complexity Based on Input Conditions for N-vehicle Problem

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Acta Mathematicae Applicatae Sinica 2010年第1期26卷 1-12页

作者： xi xia jin-chuan Cui Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100190 China

This paper proposes a method of estimating computational complexity of problem through analyzing its input condition for N-vehicle exploration problem. The N-vehicle problem is firstly formulated to determine the optimal replacement in the set of permutations of 1 to N. The complexity of the problem is factorial of N （input scale of problem）. To balance accuracy and efficiency of general algorithms, this paper mentions a new systematic algorithm design and discusses correspondence between complexity of problem and its input condition, other than just putting forward a uniform approximation algorithm as usual. This is a new technique for analyzing computation of NP problems. The method of corresponding is then presented. We finally carry out a simulation to verify the advantages of the method： 1） to decrease computation in enumeration; 2） to efficiently obtain computational complexity for any N-vehicle case; 3） to guide an algorithm design for any N-vehicle case according to its complexity estimated by the method.

关键词： Complexity of computation combinatorial optimization N-vehicle problem permutations inverse order

Multi-objective optimization of water supply network rehabilitation with non-dominated sorting Genetic Algorithm-II

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第3期9卷 391-400页

作者： xi jin Jie ZHANG jin-liang GAO Wen-yan WU School of Municipal and Environment Engineering Harbin institute of Technology Harbin 150090 China Faculty of Computing Engineering and Technology Staffordshire University Beaeonside Stafford UK

Through the transformation of hydraulic constraints into the objective functions associated with a water supply network rehabilitation problem, a non-dominated sorting Genetic Algorithm-II (NSGA-II) can be used to solve the altered multi-objective optimization model. The introduction of NSGA-II into water supply network optimal rehabilitation problem solves the conflict between one fitness value of standard genetic algorithm (SGA) and multi-objectives of rehabilitation problem. And the uncertainties brought by using weight coefficients or punish functions in conventional methods are controlled. And also by in-troduction of artificial inducement mutation (AIM) operation, the convergence speed of population is accelerated;this operation not only improves the convergence speed, but also improves the rationality and feasibility of solutions.

关键词： Water supply system Water supply network Optimal rehabilitation Multi-objective Non-dominated sorting Ge-netic Algorithm (NSGA)

Joint Algorithm of Message Fragmentation and No-Wait Scheduling for Time-Sensitive Networks

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IEEE/CAA Journal of Automatica Sinica 2021年第2期8卷 478-490页

作者： xi jin Changqing xia Nan Guan Peng Zeng Key Laboratory of Networked Control Systems Chinese Academy of SciencesShenyang 110016 Shenyang Institute of Automation Chinese Academy of SciencesShenyang 110016China Institutes for Robotics and Intelligent Manufacturing Chinese Academy of SciencesShenyang 110169China Department of Computing Hong Kong Polytechnic UniversityHong KongChina

Time-sensitive networks(TSNs)support not only traditional best-effort communications but also deterministic communications,which send each packet at a deterministic time so that the data transmissions of networked control systems can be precisely scheduled to guarantee hard real-time ***-wait scheduling is suitable for such TSNs and generates the schedules of deterministic communications with the minimal network resources so that all of the remaining resources can be used to improve the throughput of best-effort ***,due to inappropriate message fragmentation,the realtime performance of no-wait scheduling algorithms is ***,in this paper,joint algorithms of message fragmentation and no-wait scheduling are ***,a specification for the joint problem based on optimization modulo theories is proposed so that off-the-shelf solvers can be used to find optimal ***,to improve the scalability of our algorithm,the worst-case delay of messages is analyzed,and then,based on the analysis,a heuristic algorithm is proposed to construct low-delay ***,we conduct extensive test cases to evaluate our proposed *** evaluation results indicate that,compared to existing algorithms,the proposed joint algorithm improves schedulability by up to 50%.

关键词： Message fragmentation networked control system real-time scheduling time sensitive network

PROTOTYPE SURFACE MICRO- PRECISION IN FUSED DEPOSITION MODELING PROCESS

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Chinese Journal of Mechanical Engineering 2007年第1期20卷 100-106页

作者： WANG Tianming xi Juntong jin Ye School of Mechanical Engineering Shanghai Jiaotong University Shanghai 200030 China

To aim at prototype parts fabricated with fused deposition modeling （FDM） process, the problems how to improve and enhance their surface micro-precision are studied. The producing mechanism of surface roughness is explained with three aspects concretely including the principle error of rapid prototyping （RP） process, the inherent characteristics of FDM process, and some mi- cro-scratches on the surface of the extruded fiber. Based on the micro-characters of section shape of the FDM prototype, a physical model reflecting the outer shape characters is abstracted. With the physical simplified and deduced, the evaluating equations of surface roughness are acquired. According to the FDM sample parts with special design for experimental measurement, the real surface roughness values of different inclined planes are obtained. And the measuring values of surface roughness are compared with the calculation values. Furthermore, the causes of surface roughness deviation between measuring values and calculation values are respectively analyzed and studied. With the references of analytic conclusions, the measuring values of the experimental part surface are revised, and the revised values nearly accord with the calculation values. Based on the influencing principles of FDM process parameters and special post processing of FDM prototype parts, some concrete measures are proposed to reduce the surface roughness of FDM parts, and the applying effects are better.

关键词： Rapid prototyping Fused deposition modeling Micro-precision Surface roughness Post processing sequence

Guaranteed control performance robust LQG regulator for discrete-time Markovian jump systems with uncertain noise

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Journal of Systems Engineering and Electronics 2007年第4期18卷 885-891页

作者： Zhu jin xi Hongsheng xiao xiaobo Ji Haibo Dept. of Automation Univ. of Science &: technology of China Hefei 230027 P. R. China

Robust LQG problems of discrete-time Markovian jump systems with uncertain noises are investigated. The problem addressed is the construction of perturbation upper bounds on the uncertain noise covariances so as to guarantee that the deviation of the control performance remains within the precision prescribed in actual problems. Furthermore, this regulator is capable of minimizing the worst performance in an uncertain case. A numerical example is exploited to show the validity of the method.

关键词： Markovian jump systems LQG uncertain noise control performance

Prescribed Performance Tracking Control of Time-Delay Nonlinear Systems With Output Constraints

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IEEE/CAA Journal of Automatica Sinica 2024年第7期11卷 1557-1565页

作者： jin-xi Zhang Kai-Di Xu Qing-Guo Wang IEEE the State Key Laboratory of Synthetical Automation for Process Industries Northeastern UniversityShenyang 110819China Institute of Artificial Intelligence and Future Networks Beijing Normal UniversityZhuhai 519087 Guangdong Key Laboratory of Artificial Intelligence and Multi-Modal Data Processing Beijing Normal University-Hong Kong Baptist University United International CollegeZhuhai 519087

The problem of prescribed performance tracking control for unknown time-delay nonlinear systems subject to output constraints is dealt with in this paper. In contrast with related works, only the most fundamental requirements, i.e., boundedness and the local Lipschitz condition, are assumed for the allowable time delays. Moreover, we focus on the case where the reference is unknown beforehand, which renders the standard prescribed performance control designs under output constraints infeasible. To conquer these challenges, a novel robust prescribed performance control approach is put forward in this ***, a reverse tuning function is skillfully constructed and automatically generates a performance envelop for the tracking error. In addition, a unified performance analysis framework based on proof by contradiction and the barrier function is established to reveal the inherent robustness of the control system against the time delays. It turns out that the system output tracks the reference with a preassigned settling time and good accuracy,without constraint violations. A comparative simulation on a two-stage chemical reactor is carried out to illustrate the above theoretical findings.

关键词： Nonlinear systems output constraints prescribed performance reference tracking time delays