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基于多点触控桌的多用户协同地图浏览与决策

东南大学学报（自然科学版） 2010年第A02期40卷 242-247页

作者：黄伟恺陈岭陈根才浙江大学计算机科学与技术学院杭州310027

针对现有Web地图服务仅支持单用户的问题,提出基于多点触控桌的多用户协同地图浏览与决策应用设计,包括基于手势及控件的并发浏览地图的设计,以及满足多用户协同工作需求的工作状态互感知、数据共享及协商支持设计.通过实验探索用户如... 详细信息

针对现有Web地图服务仅支持单用户的问题,提出基于多点触控桌的多用户协同地图浏览与决策应用设计,包括基于手势及控件的并发浏览地图的设计,以及满足多用户协同工作需求的工作状态互感知、数据共享及协商支持设计.通过实验探索用户如何通过该应用设计进行协同地图浏览和决策以及屏幕触控点分布显示,相对于控件,用户更倾向于使用自然手势进行交互.用户问卷结果以及对用户协同工作过程的观察表明,该应用设计可有效支持多用户协同地图浏览与决策.此外,发现用户较少转变地图朝向来适应自己,用户在进行协同工作时都伴随着语言交流,且不同语言情境对应于不同的交互手势.

关键词：多点触控桌协同地图浏览决策用户界面设计

基于复合虚拟阻抗的混合储能系统功率分频协调与谐波电流抑制策略

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高电压技术 2023年第5期49卷 2017-2028页

作者：杨苓黄俊滔朱涤凡广东工业大学自动化学院广州510006

混合储能系统在传统下垂控制下不能根据蓄电池和超级电容各自的储能特点和动态响应进行功率合理分配,同时单相逆变器负荷的存在导致前级变换器和输入源产生二次谐波电流,这将缩短系统的使用寿命,破坏系统稳定运行。针对以上问题,该文提... 详细信息

混合储能系统在传统下垂控制下不能根据蓄电池和超级电容各自的储能特点和动态响应进行功率合理分配,同时单相逆变器负荷的存在导致前级变换器和输入源产生二次谐波电流,这将缩短系统的使用寿命,破坏系统稳定运行。针对以上问题,该文提出一种基于复合虚拟阻抗的功率分频协调与低频谐波电流抑制策略。在复合虚拟阻抗作用下,系统等效输出阻抗在低频段和高频段分别由蓄电池侧和超级电容侧阻抗主导,此时蓄电池提供系统功率波动的低频分量,抑制直流母线电压波动以稳定系统能量供需平衡,超级电容快速吸收系统功率波动的高频分量,提高系统的动态响应。在此基础上分析了复合虚拟阻抗使电感支路在二倍频时呈现高阻抗,非二倍频时呈现低阻抗,从而抑制二次谐波电流。最后,通过实验验证所提方法的有效性。

关键词：直流微电网混合储能系统单相逆变器负荷复合虚拟阻抗功率分频协调低频谐波电流抑制

Numerical Simulation of Rotating Stall in a Centrifugal Compressor with Vaned Diffuser

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Journal of Thermal Science 2007年第2期16卷 115-120页

作者： Weiguang huang Shaojuan Geng Junqiang Zhu Hongwu Zhang Institute of Engineering Thermophysics Chinese Academy of Sciences EO. Box 2706 Beijing 100080 China Graduate School of the Chinese Academy of Sciences

This paper reports a numerical study on the process from normal operating conditions to rotating stall in a centrifugal compressor with vaned diffuser. The purpose is to better understand the flow characteristics near stall point under the interactions between centrifugal impeller and vaned diffuser. Numerical results show that under certain conditions just preceding stall point the tip leakage vortex begins to fluctuate at roughly half of the blade passing frequency. This phenomenon is similar to rotating instability in axial compressors. With the flow rate reduced further the impeller stalls and five stall cells propagating at a frequency of 85 percent of impeller rotation speed are found.

关键词： centrifugal compressor rotating stall tip leakage flow unsteady.

Integrated water resources management for emergency situations： A case study of Macao

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Journal of Environmental Sciences 2016年第12期28卷 72-78页

作者： Jian Yong huang Inchio Lou Ying Xia Li Department of Civil and Environmental Engineering Faculty of Science and Technology University of Macao Macao SAR China State Key Laboratory of Water Environment Simulation School of Environment Beijing Normal University Beijing 100875 China

Integrated urban water management （IUWM） is a useful tool that can be used to alleviate water resource shortages in developing regions like Macao, where 98% of the raw water comes from China's Mainland. In Macao, scarce water resources deteriorate rapidly in emergency situations, such as accidental chemical spills upstream of the supply reservoir or salty tides. During these times, only the water from the two freshwater reservoirs in Macao can be used. In this study, we developed urban water management optimization models that integrated the raw water supply from the two reservoirs with various proposed governmental policies （wastewater reuse, rainwater collection, and water saving）. We then determined how various water resource strategies would influence the urban water supply in Macao in emergency situations. Our results showed that, without imported raw water, the water supply from only the two Macao reservoirs would last for 7.95 days. However, when all the government policies were included in the model, the supply could be extended to 13.79 days. Out of the three non-conventional water resources, wastewater reuse is the most beneficial for increasing the Macao water supply, and rainwater collection also has great potential.

关键词： Emergency situations Integrated urban water management Macao Non-conventional water resources

Improvement and performance of parallel multilevel fast multipole algorithm

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Journal of Systems Engineering and Electronics 2011年第1期22卷 164-169页

作者： Zhanhe Liu Peilin huang Zhe Wu Xu Gao School of Aeronautic Science and Engineering Beihang University Beijing 100191 P. R. China The First Aircraft Institute Aviation Industry Corporation of China Xi'an 710089 E R. China

The method of establishing data structures plays an important role in the efficiency of parallel multilevel fast multipole algorithm（PMLFMA）.Considering the main complements of multilevel fast multipole algorithm（MLFMA） memory,a new parallelization strategy and a modified data octree construction scheme are proposed to further reduce communication in order to improve parallel *** far interaction,a new scheme called dynamic memory allocation is *** analyze the workload balancing performance of a parallel implementation,the original concept of workload balancing factor is introduced and verified by numerical *** results show that the above measures improve the parallel efficiency and are suitable for the analysis of electrical large-scale scattering objects.

关键词： multilevel fast multipole algorithm(MLFMA) electromagnetic scattering parallelization radar cross section(RCS).

Quantitative study on interactions between interfacial misfit dislocation networks and matrix dislocations in Ni-based single crystal superalloys

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Acta Mechanica Solida Sinica 2017年第4期30卷 345-353页

作者： Jun Xiong Yaxin Zhu Zhenhuan Li Minsheng huang Department of Mechanics Huazhong University of Science and Technology State Key Laboratory of Digital Manufacturing Equipment and Technology Huazhong University of Science and Technology Hubei Key Laboratory of Engineering Structural Analysis and Safety Assessment

The interactions between the moving dislocation within matrix channel and the interfacial misfit dislocation networks on the two-phase interfaces in Ni-based single crystal superalloys are studied carefully via atomic modeling, with special focus on the factors influ- encing the critical bowing stress of moving dislocations in the matrix channel. The results show that the moving matrix dislocation type and its position with respect to the interfacial misfit dislocation segments have considerable influences on the interactions. If the moving matrix dislocation is pure screw, it reacts with the interracial misfit dislocation segments toward dislocation linear energy reduction, which decreases the critical bowing stress of screw dislocation due to dislocation linear energy release during the dislocation reactions. If the moving matrix dislocation is of 60^-mixed type, it is obstructed by the interaction between the mixed matrix dislocations and the misfit interfacial dislocation segments. As a result, the critical bowing stress increases significantly because extra interactive energy needs to be overcome. These two different effects on the critical bowing stress become in- creasingly significant when the moving matrix dislocation is very close to the interracial misfit dislocation segments. In addition, the matrix channel width also has a significant influence on the critical bowing stress, i.e. the narrower the matrix channel is, the higher the critical bowing stress is. The classical Orowan formula is modified to predict these effects on the critical bowing stress of moving matrix dislocation, which is in good agreement with the computational results.

关键词： Dislocation interaction Misfit dislocation networks Molecular dynamics Matrix dislocation Ni-based single crystal superalloys

Designing reduced beacon trajectory for sensor localization

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第12期8卷 1971-1982页

作者： huang Wen-liang LI Shi-jian LIU Duo School of Computer Science Zhejiang University Hangzhou 310027 China Graduate School Zhejiang University Hangzhou 310027 China

Localization is one of the substantial issues in wireless sensor networks. The key problem for the mobile beacon localization is how to choose the appropriate beacon trajectory. However, little research has been done on it. In this paper, firstly, we deduce the number of positions for a beacon to send a packet according to the acreage of ROI (region of interest); and next we present a novel method based on virtual force to arrange the positions in arbitrary ROI; then we apply TSP (travelling salesman problem) algorithm to the positions sequence to obtain the optimal touring path, i.e. the reduced beacon trajectory. When a mobile beacon moves along the touring path, sending RF signals at every position, the sensors in ROI can work out their position with trilateration. Experimental results demonstrate that the localization method, based on the beacon reduced path, is efficient and has flexible accuracy.

关键词： Sensor network Sensor localization Mobile beacon Virtual force

Redox-neutral ipso/ortho alkenylcyanation of(hetero)arylboronic acid enabled by 1,4-rhodium migration and fragmentation

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Science China Chemistry 2023年第8期66卷 2283-2291页

作者： Chenxia Guo Donghui Xing Huanfeng Jiang Liangbin huang The State Key Laboratory of Pulp and Paper Engineering School of Chemistry and Chemical EngineeringKey Laboratory of Functional Molecular Engineering of Guangdong ProvinceSouth China University of TechnologyGuangzhou510640China

A mild,chemoselective,redox-neutral ipso/ortho alkenylcyanation of arylboronic acids with homopropargylic malononitriles via 1,4-rhodium migration and fragmentation is reported.A variety of 2-vinyl arylnitriles are obtained in good yields(51examples,ava.69%yields)through this strategy,which is characterized by its broad substrate scope,great functional group tolerance,and mild *** studies indicate that the fragmentation is temperature *** primary asymmetric exploration for the non-fragmentation product already shows promising *** separation of the two cyano groups of homopropargylic malononitriles results in the formation of aromatic nitrile and aliphatic nitrile in one molecule,which enables the further transformations of the products.

关键词： 1,4-rhodium migration alkenylcyanation cyano transfer malononitriles

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SV波斜入射形成的动应力路径及影响因素分析

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振动与冲击 2018年第2期37卷 6-16,42页

作者：黄博李琪群凌道盛王宇浙江大学建筑工程学院岩土工程研究所杭州310058 浙江大学软弱土与环境土工教育部重点实验室杭州310058 中交第四航务工程勘察设计院有限公司广州510230

动应力路径是研究场地地震动力响应的关键。基于波动理论,推导了半无限弹性空间中任一深度处由SV波斜入射产生的动应力。在采用较大土体刚度参数,且SV波为垂直入射特例时,该方法与土动力学估算地震动应力的常规简化方法结果一致。揭示... 详细信息

动应力路径是研究场地地震动力响应的关键。基于波动理论,推导了半无限弹性空间中任一深度处由SV波斜入射产生的动应力。在采用较大土体刚度参数,且SV波为垂直入射特例时,该方法与土动力学估算地震动应力的常规简化方法结果一致。揭示了SV波斜入射下形成的动应力路径特征,从数学上证明了SV波斜入射产生的动应力在双剪应力分量(偏差正应力和水平剪应力)组成的平面中形成斜椭圆形,并进行了参数敏感性分析,表明入射角、泊松比和单位波长深度是影响应力路径的根本因素,为进一步研究斜入射地震波作用下场地动力响应奠定了理论基础。

关键词： SV波斜人射弹性半空间动应力路径双剪应力平面