检索结果-南通市图书馆

在线全文

学校读者我要写书评

暂无评论

铝电解自动控制网络安全问题及对策初探

甘肃冶金 2015年第1期37卷 120-122页

作者：姚自忠庆阳恒誉建设工程监理有限公司甘肃庆阳730335

随着计算机网络在铝电解企业自动控制及管理信息方面的广泛应用,企业的各项工作对计算机网络的依赖越来越强烈。网络使企业的各项工作驶向快车道,但也一定程度上提升了企业的运行风险。如何针对铝电解控制系统的特点和需求,分析系统面... 详细信息

随着计算机网络在铝电解企业自动控制及管理信息方面的广泛应用,企业的各项工作对计算机网络的依赖越来越强烈。网络使企业的各项工作驶向快车道,但也一定程度上提升了企业的运行风险。如何针对铝电解控制系统的特点和需求,分析系统面临的威胁,采取有效的措施保证网络安全已成为亟待解决的问题。

关键词：铝电解网络:安全问题

在线全文

学校读者我要写书评

暂无评论

运用VBA技术优化Excel报表制作流程

甘肃冶金 2013年第6期35卷 107-109,113页

作者：姚自忠中国铝业公司连城分公司甘肃兰州730335

随着办公自动化系统的发展和不断完善,基于计算机网络技术的无纸化办公得到广泛应用,无纸化办公对信息的快速合成与传递是传统办公模式无法比拟的。运用Excel电子表格的强大功能,能够方便地处理多重报表、交叉报表、复杂报表,起到事半... 详细信息

随着办公自动化系统的发展和不断完善,基于计算机网络技术的无纸化办公得到广泛应用,无纸化办公对信息的快速合成与传递是传统办公模式无法比拟的。运用Excel电子表格的强大功能,能够方便地处理多重报表、交叉报表、复杂报表,起到事半功倍的效果。本文介绍如何通过VBA(Visual Basic For Application)技术快速、准确、高效地以Excel电子表格形式展现数据统计信息。

关键词： VBA技术优化报表制作流程

Recent progress on photoactive nonprecious transition-metal complexes

在线全文

学校读者我要写书评

暂无评论

Science China Chemistry 2025年第1期 46-95页

作者： zhong-Liang Gong Hong-Jie Zhang Yan Cheng Jianxun Liu Yuhan Ai Yaqin Li Zhihui Feng Qiong Zhang Shaolong Gong Yong Chen Chang-Jiang yao Yuan-Yuan Zhu Liang-Jin Xu Yu-Wu zhong CAS Key Laboratory of Photochemistry Institute of Chemistry Chinese Academy of Sciences State Key Laboratory of Structural Cemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences School of Chemistry and Chemical Engineering Anhui Key Laboratory of Advanced Catalytic Materials and Reaction EngineeringHefei University of Technology State Key Laboratory of Explosion Science and Safety Protection School of Mechatronical Engineering Beijing Institute of Technology College of Chemistry and Molecular Sciences Hubei Key Lab on Organic and Polymeric Optoelectronic Materials Wuhan University School of Chemistry and Chemical Engineering Anhui University Key Laboratory of Photochemical Conversion and Optoelectronic Materials & CAS-HKU Joint Laboratory on New Materials Technical Institute of Physics and Chemistry Chinese Academy of Sciences

Photoactive complexes of nonprecious transition metals, mainly including those in the first-row and partially the second-row of the Periodic table of elements, have received increasing attention in view of their low cost and long-term sustainability. They are recognized as promising alternatives to noble transition metal complex congeners that have been extensively studied in optoelectronic devices, artificial photosynthesis, photocatalysis, biodiagnostics, and therapeutics, etc. This review is devoted to a comprehensive summary on the classical and recent advances on photoactive nonprecious transition metal complexes, including photoactive Zr, V, Cr, Mo, and W complexes, Mn complexes and hybrids, Fe, Co, Ni, and Cu complexes, and Zn and Cd complexes and hybrids. A particular focus is given on the molecular design, modulation of photophysical and photochemical properties, and applications of the representative and lately-developed nonprecious metal complexes. In addition, a perspective on the future development in this field is provided at the end of this review.

关键词：

同方期刊数据库

Bayesian networks modeling for thermal error of numerical control machine tools

在线全文

学校读者我要写书评

暂无评论

Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第11期9卷 1524-1530页

作者： Xin-hua yao Jian-zhong FU zi-chen CHEN College of Mechanical and Energy Engineering Zhejiang University Hangzhou 310027 China Zhejiang Provincial Key Lab of Advanced Manufacturing Technology Hangzhou 310027 China

The interaction between the heat source location, its intensity, thermal expansion coefficient, the machine system configuration and the running environment creates complex thermal behavior of a machine tool, and also makes thermal error prediction difficult. To address this issue, a novel prediction method for machine tool thermal error based on Bayesian networks (BNs) was presented. The method described causal relationships of factors inducing thermal deformation by graph theory and estimated the thermal error by Bayesian statistical techniques. Due to the effective combination of domain knowledge and sampled data, the BN method could adapt to the change of running state of machine, and obtain satisfactory prediction accuracy. Ex- periments on spindle thermal deformation were conducted to evaluate the modeling performance. Experimental results indicate that the BN method performs far better than the least squares (LS) analysis in terms of modeling estimation accuracy.

关键词： Bayesian networks (BNs) Thermal error model Numerical control (NC) machine tool

面向可持续雨洪管理的低影响开发措施综合效益评估

在线全文

学校读者我要写书评

暂无评论

天津理工大学学报 2025年第1期41卷 126-133页

作者：訾妍钟炜天津理工大学管理学院

为满足低影响开发(low impact development, LID)组合在城市雨洪管理过程中良好的应用效果和经济效益，应用暴雨洪水管理模型(stormwater management model, SWMM)结果指标和项目全生命周期成本理论，构建不同LID组合方案下的环境-成本... 详细信息

为满足低影响开发(low impact development, LID)组合在城市雨洪管理过程中良好的应用效果和经济效益，应用暴雨洪水管理模型(stormwater management model, SWMM)结果指标和项目全生命周期成本理论，构建不同LID组合方案下的环境-成本效益综合评价系统，并通过数值模拟和数理分析相结合的方法评估各备选方案的综合效益。为验证理论模型的可行性，将9种不同布设比例的LID组合分别嵌入实际项目中进行模拟和评估。结果表明，综合效益最高的LID组合为“45%的绿色屋顶+15%的植草沟+30%的雨水花园+70%的透水铺装”,其径流总量削减率为52.83%、4类污染负荷削减率均为80%以上且每年消耗的总成本费用为22 416 350元。该评价体系为优化城市可持续雨洪管理提供新思路，同时为建设开发海绵城市提供方案指导。

关键词：低影响开发综合效益评估暴雨洪水管理模型可持续雨洪管理海绵城市

Investigations of the dynamical behaviors of a millimeter-scale cavitation bubble near the rigid wall

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Journal of Hydrodynamics 2023年第6期35卷 1064-1076页

作者： Dan zi Dong-qiao He Zhi-feng yao Fu-jun Wang Qiang zhong Pin Lyu College of Water Resources and Civil Engineering China Agricultural UniversityBeijing100083China Beijing Engineering Research Center of Safety and Energy Saving Technology for Water Supply Network System Beijing100083China Yichang Testing Technology Research Institute Yichang443000China

The collapse of the cavitation bubble near the rigid wall emits shock waves and creates micro-jet,causing cavitation damage and operation instability of the hydraulic *** this paper,the millimeter-scale bubble near the rigid wall was investigated experimentally and numerically with the help of a laser photogrammetry system with nanosecond-micron space-time resolution and the open source package *** morphological characteristics of the bubble during its growth phase,collapse phase and rebound phase were observed by experiment and numerical simulation,and characteristics of the accompanying phenomena including the shock wave propagation and micro-jet evolution were well *** numerical results agree well with the experimental *** bubble starts from a tiny small size with high internal pressure and expands into a sphere with a radius of 1.07 mm forγ=d/R_(max)=*** bubble collapses into a heart shape and moves towards to the rigid wall during its collapse phase,resulting in a higher pressure load for the rigid wall in the second *** maximum pressure of the shock wave of the first bubble collapse phase reaches 5.4 MPa,and the velocity of the micro-jet reaches approximately 100 m/*** study enriches the existing experimental and numerical results of the dynamics of the near-wall cavitation bubble.

关键词： Cavitation bubble collapse shock wave micro jet the rigid wall

Deflection of cavitation bubble near the rigid wall with a gas-containing hole

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Hydrodynamics 2023年第2期35卷 330-337页

作者： Yu-rong Sun Qiang zhong Zhi-feng yao Dan zi Ruo-fu Xiao Fu-jun Wang College of Water Resources and Civil Engineering China Agricultural UniversityBeijing100083China Beijing Engineering Research Center of Safety and Energy Saving Technology for Water Supply Network System Beijing100083China

The presence of a rigid wall causes a microjet of the cavitation bubble to collapse to move toward the wall,while a free surface does the *** a rigid wall surface is combined with a free surface,it may affect the direction of the *** motive of this study is to find out the influence of the dynamic behavior of a laser-induced bubble near the rigid wall with a gas-containing *** of the bubble at different distances from the gas-containing hole in the horizontal and vertical directions were recorded by a high-speed camera(2.3×10^(5) fps).When the bubble collapse near the boundary,the bubble will produce two situations:away from or toward the *** focuses on the direction of the bubble,the oscillation period of a bubble,and reflection angle,and quantitative analysis of the *** was found that the boundary not only changes the morphologic of the bubble and the overall direction of movement but also affects the oscillation *** addition,it can control the deflection of the bubble.

关键词： Cavitation bubble bubble migration deflection angle gas-containing hole

Summer extreme precipitation patterns and synoptic-scale circulation precursors over the Tibetan Plateau

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science China Earth Sciences 2024年第5期67卷 1625-1638页

作者： Zhiyuan DING yao HA zhong zhong College of Meteorology and Oceanography National University of Defense TechnologyChangsha 410073China Key Laboratory for Virtual Geographic Environment School of Geography ScienceNanjing Normal UniversityNanjing 210023China Jiangsu Collaborative Innovation Center for Climate Change School of Atmospheric SciencesNanjing UniversityNanjing 210023China

In the context of global warming,the extreme summer precipitation over the Tibetan Plateau(TP)has changed *** this study,the summer(June–August)extreme precipitation on the TP was classified into three spatial types by applying the K-means clustering method to the Third Pole Region long time-series high-resolution(1/30°)precipitation dataset(TPHi Pr,1979–2020).The characteristics of the circulation anomalies and precursors corresponding to the extreme precipitation on the TP in summer during 1979–2020 were *** results showed that the summer extreme precipitation of the TP can be categorized into northwestern(NW),southeastern(SE),and southern Himalayan(HS)types based on extreme precipitation *** NW and SE types are mainly influenced by anomalous signals in the mid-to-high latitude regions upstream of them,whereas the HS type is controlled by the localized subtropical anomalous *** the 8th day before the onset of the NW type,an anomalous cyclone was observed in the western Atlantic Ocean(60°W,50°N),which triggered the west-to-east quasi-latitudinal propagation of Rossby *** the onset day of the NW type,the upper troposphere showed positive-negative-positive geopotential height anomalies along the latitudinal 40°N from the Caspian Sea,the western part of Xinjiang,to the northeastern *** entered from the Arabian Sea along the southeastern edge of the anomalous cyclone on the southwestern TP and converged in the northwestern *** to the NW type,the precursors of the SE type appeared at higher latitudes and were more *** the 8th day before the onset of the SE type,an anomalous cyclone occurred near Greenland(60°W,70°N)and excited Rossby waves propagating *** the onset day of the SE type,the upper troposphere showed negative-positive-negative geopotential height anomalies across Eurasia from the Ural Mountains and the Iranian Plateau to the northern TP in the northwest-southeast directi

关键词： Tibetan Plateau Summer extreme precipitation Atmospheric circulation anomaly Precursor Teleconnection wave train

在线全文

学校读者我要写书评

暂无评论

服务器无感知计算系统性能优化技术研究综述

软件学报 2025年第1期36卷 47-78页

作者：杨光刘杰曲慕子王帅叶丹钟华中国科学院大学中国科学院软件研究所软件工程技术研究开发中心计算机科学国家重点实验室(中国科学院软件研究所)

服务器无感知计算是新兴的云计算模式,它基于“函数即服务(FaaS)”的范式,以函数为部署和调度的基本单位,为用户提供大规模并行和自动伸缩的函数执行服务,且无需用户管理底层资源.对于用户,服务器无感知计算能够帮助他们摆脱集群底层基... 详细信息

服务器无感知计算是新兴的云计算模式,它基于“函数即服务(FaaS)”的范式,以函数为部署和调度的基本单位,为用户提供大规模并行和自动伸缩的函数执行服务,且无需用户管理底层资源.对于用户,服务器无感知计算能够帮助他们摆脱集群底层基础设施管理的负担,专注于业务层的开发和创新;对于服务提供商,服务器无感知计算将应用分解为细粒度的函数,极大地提高了调度效率和资源利用率.显著的优势让服务器无感知计算迅速吸引了业界的注意,然而,服务器无感知计算与传统云计算迥然不同的计算模式以及对任务各方面的严格限制给应用的迁移带来了诸多障碍,各种越来越复杂的任务也对服务器无感知计算的性能提出了越来越高的要求,服务器无感知计算的性能优化成为一个重要的研究课题.从4个方面对服务器无感知计算系统性能优化技术的相关研究工作进行梳理和综述,并介绍现有的系统实现.(1)介绍面向典型任务的优化技术,包括任务适配和针对特定任务的系统优化;(2)综述沙箱环境的优化工作,包括沙箱方案和冷启动优化技术,它们是决定函数运行速度的核心;(3)概括I/O和通信技术的优化,它们是服务器无感知计算应用程序的主要性能瓶颈;(4)简述相关的资源调度技术,包括面向平台和面向用户的调度策略,它们决定着系统的资源利用率和任务的执行效率.最后,总结当前服务器无感知计算性能优化技术所面临的问题和挑战,并展望未来可能的发展方向.

关键词：服务器无感知计算函数即服务云函数云计算性能优化