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Science China(Information Sciences) 2024年第2期67卷 20-40页

作者： Peng YANG Laoming ZHANG haifeng liu Guiying LI Department of Statistics and Data Science Southern University of Science and Technology Guangdong Provincial Key Laboratory of Brain-Inspired Intelligent Computation Department of Computer Science and EngineeringSouthern University of Science and Technology Academy for Advanced Interdisciplinary Studies Southern University of Science and Technology Guangdong OPPO Mobile Telecommunications Corp. Ltd Research Institute of Trustworthy Autonomous Systems Southern University of Science and Technology

In recent years, various companies have started to shift their data services from traditional data centers to the cloud. One of the major motivations is to save on operational costs with the aid of cloud elasticity. This paper discusses an emerging need from financial services to reduce the incidence of idle servers retaining very few user connections, without disconnecting them from the server side. This paper considers this need as a bi-objective online load balancing problem. A neural network based scalable policy is designed to route user requests to varied numbers of servers for the required elasticity. An evolutionary multi-objective training framework is proposed to optimize the weights of the policy. Not only is the new objective of idleness reduced by over 130% more than traditional industrial solutions, but the original load balancing objective itself is also slightly improved. Extensive simulations with both synthetic and real-world data help reveal the detailed applicability of the proposed method to the emergent problem of reducing idleness in financial services.

关键词： evolutionary reinforcement learning evolutionary multi-objective optimization load balance cloud computing

A modified 3D mean strain energy density criterion for predicting shale mixed-mode I/III fracture toughness

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第7期16卷 2411-2428页

作者： Kun Zheng Chaolin Wang Yu Zhao Jing Bi haifeng liu College of Civil Engineering Guizhou UniversityGuiyang550025China State Key Laboratory of Geomechanics and Geotechnical Engineering Institute of Rock and Soil MechanicsChinese Academy of SciencesWuhan430071China

The fracture toughness of rocks is a critical fracturing parameter in geo-energy exploitation playing a significant role in fracture mechanics and hydraulic *** edge-notched disk bending(ENDB)specimens are employed to measure the entire range of mixed-modeⅠ/Ⅲfracture toughness of Longmaxi *** theoretically interpret the fracture mechanisms,this research first introduces the detailed derivations of three established fracture *** distinguishing the volumetric and distortional strain energy densities,an improved three-dimensional mean strain energy density(MSED)criterion is *** the critical volumetric to distortional MSED ratio decreases,the transition from tensiondominated fracture to shear-dominated fracture is *** results indicate that both peak load and applied energy increase significantly with the transition from pure mode I(i.e.,tension)to pure modeⅢ(i.e.,torsion or tearing)since mode-Ⅲcracking happens in a twisted manner and mode-Ⅰcracking occurs in a coplanar *** macroscopic fracture signatures are consistent with those of triaxial hydraulic *** average ratio of pure mode-Ⅲfracture toughness to pure mode-Ⅰfracture toughness is 0.68,indicating that the obtained mode-Ⅲfracture resistance for a tensionbased loading system is apparent rather than *** to the three mainstream fracture criteria,the present fracture criterion exhibits greater competitiveness and can successfully evaluate and predict mixed-modeⅠ/Ⅲfracture toughness of distinct materials and loading methods.

关键词： Longmaxi shale Hydraulic fracturing Fracture mechanisms Fracture criteria Mixed-mode I/III fracture toughness Edge-notched disk bending

Influence of syngas components and ash particles on the radiative heat transfer in a radiant syngas cooler

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Chinese Journal of Chemical Engineering 2024年第4期68卷 203-215页

作者： Chen Han Youmin Situ Huaxing Zhu Jianliang Xu Zhenghua Dai Guangsuo Yu haifeng liu National Energy Coal Gasification Technology Research and Development Center East China University of Science and TechnologyShanghai 200237China Shanghai Engineering Research Center of Coal Gasification East China University of Science and TechnologyShanghai 200237China

Radiant syngas cooler(RSC)is widely used as a waste heat recovery equipment in industrial *** this work,an RSC with radiation screens is established and the impact of gaseous radiative property models,gas components,and ash particles on heat transfer is investigated by the numerical simulation *** the syngas components and the pressure environment of the RSC,a modified weighted-sum-of-gray-gases model was *** modified model shows high accuracy in *** computational fluid dynamics simulation,the calculated steam production is only 0.63%in error with the industrial *** with Smith's model,the temperature decay along the axial direction calculated by the modified model is *** components are of great significance to heat recovery capacity,especially when the absorbing gas fraction is less than 10%.After considering the influence of particles,the outlet temperature and the proportion of radiative heat transfer are less affected,but the difference in steam output reaches 2.7 t·h^(-1).The particle deposition on the wall greatly reduces the heat recovery performance of an RSC.

关键词： Radiant syngas cooler Weighted-sum-of-gray-gases model Numerical simulation Particle radiation

Laser image refractive index sensor based on the combination of a coreless optical fiber and a digital camera

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Optoelectronics Letters 2024年

作者： GUO Jingzhong LAN Feng CHEN Xiang liu haifeng Xi'an Institute of Space Radio Technology Key Laboratory of Optoelectronic Sensor and Sensing Network Technology College of Electronic Information and Optical Engineering Nankai University

As a laser passes through a scattering medium， the light interacts with the irregular reflections within the medium， resulting in light scattering and the formation of speckles. In this paper， an image sensor based on the combination of a coreless optical fiber and a digital camera is proposed for liquid refractive index sensing applications. The coreless fiber is used as a sensing unit， and the change in the speckle pattern is measured using the digital correlation method to detect the magnitude of the liquid’s refractive index. The experimental results indicate that the laser image sensing technique is capable of effectively distinguishing liquid samples with refractive indices ranging from 1.3328 to 1.3908， with a sensing sensitivity of -1.306 RIU-1. Moreover， the laser image sensing technique， with its advantages of high experimental reproducibility， simple system design， remote over-control， holds great research significance and potential application in laser communication and sensor integration.

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Research progress of integrated optical gyroscope

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Chinese Optics Letters 2024年第3期22卷 42-49页

作者：郭宏杰刘海锋雷明谭满清宋志刚 Institute of Semiconductors Chinese Academy of SciencesBeijing 100083China College of Materials Science and Opto-electronics Technology University of Chinese Academy of SciencesBeijing 100049China Beijing Huairou Instruments and Sensors Co. Ltd.Beijing 101400China Beijing Institute of Automation and Control Equipment Key Laboratory of National Defense Science and Technology of Inertial TechnologyBeijing 100074China

Integrated optical gyroscopes(IOGs)have been an efficient tool for numerous applications in various fields,including inertial navigation,flight control,and earthquake ***,we review the progress of integrated optical gyroscopes based on two categories of integrated interferometric optical gyroscopes(IIOGs)and integrated resonant optical gyroscopes(IROGs).

关键词： integrated optical gyroscopes interferometric optical gyroscopes integrated resonant optical gyroscopes

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新高考改革的三个阶段与未来展望

江苏高教 2024年第8期 1-3页

作者：刘海峰浙江大学科举学与考试研究中心杭州310058

考试招生制度是国家基本教育制度,高考综合改革是教育领域“牵一发而动全身”的重大改革,是牵动中国教育改革的“牛鼻子”,备受社会各界关注。2014年9月,《国务院关于深化考试招生制度改革的实施意见》发布,标志着新一轮高考改革的正式... 详细信息

考试招生制度是国家基本教育制度,高考综合改革是教育领域“牵一发而动全身”的重大改革,是牵动中国教育改革的“牛鼻子”,备受社会各界关注。2014年9月,《国务院关于深化考试招生制度改革的实施意见》发布,标志着新一轮高考改革的正式启动。以科目改革为核心的新高考改革已成为统一高考建制以来,牵涉范围最广、改革力度最大的一次变革。今年作为新高考改革实施十年的关键节点,有需要更有必要总结十年的改革成效与现实挑战,以进一步完善新高考改革,为拔尖创新人才培养与教育强国建设探寻新的思路与方向。2024年5月,在厦门大学召开了“新高考改革与发展学术研讨会”,多位领域内专家就新高考改革的关键议题作了深入探讨。本刊遴选以下5篇有代表性发言以飨读者。

关键词：考试招生制度新高考改革拔尖创新人才培养中国教育改革教育强国改革成效统一高考十年

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不同利益相关主体对高考制度评价的实证研究

华东师范大学学报（教育科学版） 2024年第3期42卷 1-11页

作者：刘海峰韦骅峰浙江大学科举学与考试研究中心杭州310058

基于83694份“高考改革问卷调查”有效数据,考察高中生、大学生、高中教师、大学教师、家长与关心高考改革的社会人士五个利益相关主体对高考制度的评价。通过词频分析可知,“公平性”“高竞争”“压力大”是各利益相关主体对高考制度... 详细信息

基于83694份“高考改革问卷调查”有效数据,考察高中生、大学生、高中教师、大学教师、家长与关心高考改革的社会人士五个利益相关主体对高考制度的评价。通过词频分析可知,“公平性”“高竞争”“压力大”是各利益相关主体对高考制度最广泛而突出的评价。通过熵值分析发现,各利益相关主体对高考制度评价同中有异,表现出不同利益诉求。通过聚类分析则进一步验证和深化了词频分析和熵值分析所获得的各项结论。鉴于此,应明确维护高考公平仍是高考改革最重要的前提条件,兼顾各主体的利益诉求,同时对高考改革的政策评价也应予以适当延展时间。

关键词：高考评价新高考改革高考公平高考改革问卷调查利益相关主体

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清代书院课艺:联结书院学与科举学的历史文献

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大学教育科学 2024年第3期 101-111页

作者：刘海峰赵凯浙江大学科举学与考试研究中心杭州310058

在上千年的中国书院史上,多数书院都重视以考促学。从流传形态来看,清代书院课艺主要分为课艺原件、编入别集中的课艺和以书院名义选编的课艺总集三大类别;就主课艺内容而言,清代书院课艺大体包括制艺试帖、经史词章、时务西学等门类。... 详细信息

在上千年的中国书院史上,多数书院都重视以考促学。从流传形态来看,清代书院课艺主要分为课艺原件、编入别集中的课艺和以书院名义选编的课艺总集三大类别;就主课艺内容而言,清代书院课艺大体包括制艺试帖、经史词章、时务西学等门类。书院课艺数量与书院数量、考课次数、书院额数和刊刻频率直接相关。尽管历史上汗牛充栋的书院课艺多已散佚,但其现存数量依旧十分巨大,无法准确估算。清代书院课艺具有一定的经学、文学、史学、书院学和科举学价值,深入挖掘其中的有用元素,可以从书院考课内容与科举考试内容、考课衡文标准与科举衡文标准、书院育人目标与科举取士目标、科举人物的思想观念与关系网络、书院生徒平时成绩与科考录取率等方面,考察书院学与科举学的共生和互动关系。

关键词：清代书院课艺书院学科举学联结

家庭资本是否影响高中生高考公平性评价——基于混合研究设计的分析

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教育发展研究 2024年第12期44卷 17-26页

作者：刘海峰韦骅峰浙江大学科举学与考试研究中心杭州310058 湖南大学教育科学研究院长沙410082

基于18355份“3+1+2”模式高中生的调查数据,通过混合研究方法,分析家庭资本是否影响高中生的高考公平性评价,并对其成因进行解释。量化研究表明:家庭资本不会影响高中生对高考改革与录取结果公平的评价,但家庭经济与文化资本能显著影... 详细信息

基于18355份“3+1+2”模式高中生的调查数据,通过混合研究方法,分析家庭资本是否影响高中生的高考公平性评价,并对其成因进行解释。量化研究表明:家庭资本不会影响高中生对高考改革与录取结果公平的评价,但家庭经济与文化资本能显著影响高中生对高考加分政策公平的评价,即家庭经济与文化资本越高的高中生越认同取消高考加分更有利于维护高考公平。质性访谈发现:不同家庭资本的高中生均认可高考改革和录取结果公正性,但不同家庭经济与文化资本的高中生对高考加分政策持有不同态度,其矛盾焦点在于高考加分政策覆盖范围和落实过程的规范性,以及具体加分分值的合理性。为此,研究建议:以规范化改革维护高考制度公平性的同时,也应适当关照弱势群体和特殊群体,并进一步完善高考加分资格审核。

关键词：高考公平性家庭资本高中生高考问卷调查 “3+1+2”模式

竖直管气动物流传输系统管道压降和传送瓶输送特性

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化工学报 2024年第7期75卷 2465-2473页

作者：吴邦汉林定标陆海峰郭晓镭刘海峰华东理工大学上海煤气化工程技术研究中心煤液化气化及高效低碳利用全国重点实验室上海200237 浙江海畅气体股份有限公司浙江台州317000

气动物流传输系统在医疗、化工等行业得到广泛应用,管道压降和特征速度是竖直管气动物流传输系统设计的关键参数,但目前相关报道很少。基于实验室自主搭建的竖直管气动物流传输系统,开展压缩气流输送传送瓶实验,进行输送特性分析以及管... 详细信息

气动物流传输系统在医疗、化工等行业得到广泛应用,管道压降和特征速度是竖直管气动物流传输系统设计的关键参数,但目前相关报道很少。基于实验室自主搭建的竖直管气动物流传输系统,开展压缩气流输送传送瓶实验,进行输送特性分析以及管道压降和特征速度的建模研究。首先借助压降信号分析、高速摄像与数据处理等方法,分析了传送瓶输送特性,提出了基于管道压降信号分析的传送瓶运动状态识别方法;其次综合考虑流道结构特征,建立了竖直管气动物流传输系统的管道压降模型,并通过数据回归获得了管道阻力系数;最后基于力平衡分析、机械能守恒定律建立了竖直管气动物流传输系统特征速度的预测模型,为传送瓶状态识别及追踪监测提供了一种新方法。

关键词：气动物流传输管道压降特征速度多相流气力输送流体动力学

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