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智能拉深件工艺设计系统的关键技术

上海交通大学学报 2000年第3期34卷 306-309页

作者：姚华陈军陶宏之阮雪榆上海交通大学塑性成形工程系上海200030

应用特征技术和人工智能技术,建立了基于特征的智能拉深类零件工艺设计系统框架,研究并实现了其中的关键技术.由于拉深成形工艺中零件形成的独特方法,面向拉深的特征以复杂的曲面特征为主.讨论了拉深类零件中几何特征向工艺特征的转换,... 详细信息

应用特征技术和人工智能技术,建立了基于特征的智能拉深类零件工艺设计系统框架,研究并实现了其中的关键技术.由于拉深成形工艺中零件形成的独特方法,面向拉深的特征以复杂的曲面特征为主.讨论了拉深类零件中几何特征向工艺特征的转换,提出了模糊决策表技术在工艺设计中的应用,应用BP神经网络方法预测了方盒件理想毛坯外形.通过人工智能技术建立起基于特征的工艺设计知识库。

关键词：工艺设计系统特征技术人工智能拉深类零件

基于功率分配的混合动力叉车系统及控制策略研究

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现代制造技术与装备 2024年第7期60卷 185-188页

作者：张华俊张军安徽合力股份有限公司合肥230601 安徽省工业车辆重点实验室合肥230601

叉车作业是物料搬运领域的重要环节。近年来,内燃叉车的排放要求不断升级,为实现节能减排、降低燃油消耗的目标,同时满足多班制连续性作业场景的需求,提出一种基于功率分配的混合动力叉车系统及其控制方案。通过对行走系统采用内燃机与... 详细信息

叉车作业是物料搬运领域的重要环节。近年来,内燃叉车的排放要求不断升级,为实现节能减排、降低燃油消耗的目标,同时满足多班制连续性作业场景的需求,提出一种基于功率分配的混合动力叉车系统及其控制方案。通过对行走系统采用内燃机与电动机动力耦合的方式,解决了传统内燃叉车在爬坡、重载起升等工况的大扭矩需求,同时避免了在平地运行、小负载起升时因实际有用功需求不多而导致的内燃机无用功的消耗,从而在本质上提高系统的有用功占比,达到节约能源的目的。通过实际应用测试,所提出的混合动力叉车系统的节油率可以达到30%以上。

关键词：叉车混合动力系统功率分配控制策略

基于现代学徒制的“双导师”教学团队建设研究

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湖北开放职业学院学报 2024年第13期37卷 65-67页

作者：刘俊吴瑛谭苗湖南都市职业学院湖南长沙410100

现代学徒制是一种以职业学校与企业联合培养人才为主要特征的人才培养模式。作为职业学校培养人才的主体,教师在其中发挥着至关重要的作用,现代学徒制要求教师具有一定的理论水平和实践能力,在中国特色现代学徒制条件下,“双导师”的教... 详细信息

现代学徒制是一种以职业学校与企业联合培养人才为主要特征的人才培养模式。作为职业学校培养人才的主体,教师在其中发挥着至关重要的作用,现代学徒制要求教师具有一定的理论水平和实践能力,在中国特色现代学徒制条件下,“双导师”的教师队伍可以为学员提供更高质量的教育资源,更有效地提高学员的综合素质。在建立“双导师”教学团队的过程中,教师自身的专业素养是非常重要的。当前,我国对“双导师”的培养还处在一个探索的阶段。文章针对目前“双导师”教师队伍建设中出现的一些问题,结合我校的实际情况,对如何构建高校教师队伍进行了有益的探索。

关键词：现代学徒制双导师建设措施

An Energy-Saving Task Scheduling Strategy Based on Vacation Queuing Theory in Cloud Computing

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Tsinghua Science and Technology 2015年第1期20卷 28-39页

作者： Chunling Cheng jun Li Ying Wang College of Computer Nanjing University of Posts and Telecommunications

High energy consumption is one of the key issues of cloud computing systems. Incoming jobs in cloud computing environments have the nature of randomness, and compute nodes have to be powered on all the time to await incoming tasks. This results in a great waste of energy. An energy-saving task scheduling algorithm based on the vacation queuing model for cloud computing systems is proposed in this paper. First, we use the vacation queuing model with exhaustive service to model the task schedule of a heterogeneous cloud computing ***, based on the busy period and busy cycle under steady state, we analyze the expectations of task sojourn time and energy consumption of compute nodes in the heterogeneous cloud computing system. Subsequently, we propose a task scheduling algorithm based on similar tasks to reduce the energy consumption. Simulation results show that the proposed algorithm can reduce the energy consumption of the cloud computing system effectively while meeting the task performance.

关键词： cloud computing independent task scheduling energy-saving vacation queuing theory

The energy release rate for hygrothermal coupling elastic materials

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Acta Mechanica Sinica 2006年第1期22卷 28-33页

作者： Fan Yang jun Wang Dapeng Chen Institute of Computational Engineering and Science Southwest Jiaotong UniversityChengdu 610031 China Department of Material Science Fudan UniversityShanjzhai 200433. China

In the fracture problems of hydrophilic elastic materials under coupling effects of heat conduction, moisture diffusion and mechanical deformation, the conventional J-integral is no longer path independent. The value of J is unequal to the energy release rate in hygrothermal coupling cases. In the present paper, we derived a general form of the energy release rate for hygrothermal fracture problems of the hydrophilic elastic materials on the basis of energy balance equation in cracked areas. By introducing the constitutive relations and the essential equations of irreversible thermodynamics, a specific expression of the energy release rate was obtained, and the expression can be reformmulated as path independent integrals, which is equivalent to the energy release rate of the fracture body. The path independence of the integrals is then verified numerically.

关键词： Fracture Energy release rate J-integral Hygrothermal coupling problems

SEASONAL REVERSE OF SEA SURFACE SLOPE IN THE NORTHERN YELLOW SEA AND ITS DYNAMIC RELATION WITH MONSOON EFFECTS

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Journal of Hydrodynamics 2004年第5期16卷 582-589页

作者： PUShu-zhen CHENGjun ZHANGYi-jun SHIQiang KeyLaboratoryofMarineScienceandNumericalModeling TheFirstInstituteofOceanographyStateOceanicAdministrationQingdao266061China MarineInformationCenter StateOceanicAdministrationTianjin300171China NorthSeaBranchofStateOceanicAdministration Qingdao266033China

Based on the monthly average sea level data from the tide gauge measurement(1999-2001), the seasonal variability of the sea level in the Northern and Middle Yellow Sea isstudied to reveal that the sea surface height at all the tide gauges becomes higher in summer thanthat in winter. In addition, the sea surface height of the Northern Yellow Sea is higher than theone of the Middle Yellow Sea with a slope downward from the north to the south in summer, while itis lower with a reversed slope in winter. The seasonal reverse of the sea surface slope can beattributed to the monsoon effects i. e. the annual reverse of the monsoon direction and the annualvariation of the monsoon rainfall. A set of equations are established in light of the dynamicprinciples to expound how the monsoon forcing and the sea surface slope generate a summer outflowand a winter inflow in the Yellow Sea.

关键词： Yellow Sea sea surface slope monsoon driven current dynamics

Plastic deformation analysis and forming quality prediction of tube N C bending

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Chinese Journal of Aeronautics 2016年第5期29卷 1436-1444页

作者： Lu Shiqiang Fang jun Wang Kelu National Defense Key Disciplines Laboratory of Light Alloy Processing Science and Technology School of Aeronautical Manufacturing Engineering Nanchang Hangkong University Nanchang 330063 China Jiangxi Key Laboratory of Surface Engineering Jiangxi Science and Technology Normal University Nanchang 330013 China

Plane strain assumption and exponent hardening law are used to investigate the plastic deformation in tube bending. Some theoretical formulae including stress, curvature radius of neutral layer, angle of neutral layer deviation, bending moment, wall thickness variation and crosssection distortion, are developed to explain the phenomena in tube bending and their magnitudes are also determined. During unloading process, the springback angle is deduced using the virtual work principle, and springback radius is also given according to the length of the neutral layer which remains unchanged before and after springback. The theoretical formulae are validated by the experimental results or the validated simulation results in literature, which can be used to auicklv predict the forming aualitv of tube numerical control （NC） bending.

关键词： Forming quality Plane strain Tube NC bending Theoretical analysis Virtual work principle

Target detection using CDMA based passive bistatic radar

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Journal of Systems Engineering and Electronics 2012年第6期23卷 858-865页

作者： Haitao Wang jun Wang Hongwei Li National Lab of Radar Signal Processing Xidian University Xi'an 710071 R R. China

Recently, the code division multiple access （CDMA） waveform exists in the large area across the world. However, when using the CDMA system as the illuminator of opportunity for the passive bistatic radar （PBR）, there exists interference not only from the base station used as the illuminator of opportunity but also from other base stations with the same frequency. And be cause in the CDMA system, the signal transmitted by each base station is different, using the direct signal of one base station can not cancel the interference from other base stations. A CDMA based PBR using an element linear array antenna as both the reference antenna and surveillance antenna is introduced. To deal with the interference in this PBR system, an adaptive temporal cancellation algorithm is used to remove the interference from the base station used as the illuminator of opportunity firstly. And then a robust adaptive beamformer is used to suppress the interference from other base stations. Finally, the preliminary experiment re sults demonstrate the feasibility of using CDMA signals as a radar waveform.

关键词： passive bistatic radar (PBR) code division multipleaccess (CDMA) signal interference suppression target detection.

Influences of Inflow Condition on Non-Axisymmetric Flows in Turbine Exhaust Hoods

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Journal of Thermal Science 2008年第4期17卷 305-313页

作者： Jing-Lun FU Jian-jun LIU Institute of Engineering ThermophysicsChinese Academy of Sciences Beijing 100190 China

The complex 3D flow in a steam turbine exhaust hood model with different inlet swirl and inlet total pressure radial distributions has been simulated by employing CFX-5 and analyzed in this paper. It＇s found that the inlet tangential flow angle at hub has a negative effect on the exhaust hood performance, while a negative gradient of inlet total pressure radial distribution has a positive impact on the hood performances. It＇s also numerically con- firmed that a proper distribution of total pressure at hood inlet can successfully eliminate the negative effects caused by the inappropriate inlet swirl distribution and improve the hood aerodynamic performance.

关键词： turbine exhaust hood inflow conditions non-axisymmetric flow