压铸充型过程模拟并行搜索算法

压铸过程充型模拟技术存在的主要问题之一是迭代过程缓慢而导致计算效率较低。该文通过对压铸充型的数学模型和计算模型进行分析 ,利用机群计算平台 ,提出并建立了一种并行搜索计算模型。该模型在原有串行算法的基础上 ,通过效率参数的适当选择和调整 ,实现了利用并行计算优化串行过程的目的。这种算法可以充分发挥各个结点的计算能力 ,有效降低结点之间的通信时间。通过对实际压铸零件进行的计算测试表明 ,该算法在保证原有计算精度的前提下 ,可以在一定范围内极大地提高计算效率。     

基于Dijkstra算法的最优路径搜索方法

针对传统Dijkstra算法在应用中存在的不足,提出了一种基于Dijkstra算法的最优路径搜索方法.该方法设计了区域限定模型,以避免大量无用结点参与计算带来的时间和空间的浪费.在此限定区域内使用优化的存储结构实现了含有启发式信息的搜索策略.路网实验结果表明,应用启发式搜索策略使搜索的路径结点总数和计算时间明显减少,搜索过程能够快速地趋于目标结点.     

基于RMI的集中式并行动态负载平衡算法

介绍了并行算法中常用的动态负载平衡技术,并分析了RMI的工作原理,提出了一种基于RMI的集中式并行动态负载平衡算法.该算法最大的特点是不需要保存结点的负载信息,可有效地减少各节点之间通信和同步所需的时间,同时结合了RMI的运行机制和JAVA的线程机制,由子结点根据自己的负载情况动态地推动任务的划分和分配,可以在多结点的并行搜索计算中获得较高的加速比和效率.通过在33个结点的并行机上的试验,证明了该算法的可行性和有效性     

一种降低垂直分层空时码球解码复杂度的自适应调制

针对垂直分层空时码球解码算法复杂度高的问题，提出了一种新的基于部分信息反馈的自适应调制算法．该算法首先根据每个发送天线总功率增益，选择该天线所用星座图大小，保持每次传输的总码率恒定，然后调整码元解码顺序，减少球解码总的搜索结点数，对于不同调制方式的复信号点球解码算法，给出了不同的结点搜索方法．由于球解码查找树根结点的减少，避免了低自由度信道系数引起的额外搜索，因此降低了迭代搜索次数．仿真结果表明，对于3天线垂直分层码，3bit反馈信息使球解码的迭代次数降低了50％，而且提高了系统性能．     

异构环境下基于任务交互图的调度算法

针对异构环境下任务图为TIG（task interaction graph）的问题，利用松弛标记法善于利用邻居属性处理大量约束的特点，提出一种任务调度算法．算法把任务看作目标对象，处理器单元看作待分配标记，根据对象间所有可能关系，逐渐排除不相关的处理器单元，选择计算和通信综合性能较好的处理器单元．在兼顾任务执行的计算和通信需求的情况下，能够合理分配资源、提高处理速度、缩短整个应用程序的执行时间．实验结果与用穷举法得出的最优结果比较显示，本算法能较理想地解决异构环境下基于任务交互图的调度问题．     

智能疏散系统导向标志计算及疏散路径仿真

为了解决大型综合建筑中智能疏散系统在火灾等突发情况发生时可根据复杂建筑结构规划出合理、安全的疏散路径问题,提出了一种基于改进A~*算法的多起点、多出口路径规划方法。通过增加转弯惩罚值,结合火灾影响区域实时信息和火灾中心点的距离改进了估价函数,进而计算出最优疏散路径。依据搜索出的最优路径调整三维楼层地图中各个导向标志方向,从而引导不同位置人员从最优路径疏散逃生。仿真实验结果表明,在计算多起点、多出口疏散路径时,改进A~*算法与传统Dijkstra算法和A~*算法相比,搜索方向更加明确,路径更加平滑,搜索效率更高,运行时间更短,并能结合火灾信息保证疏散路径的安全性。该算法在求解大型综合建筑火灾安全疏散路径方面具有很好的应用前景。     

基于 DLL 的 Windows 任务通信的消息队列

Ｗｉｎｄｏｗｓ利用动态连接库ＤＬＬ可为所有应用程序提供代码和数据的共享，基于ＤＬＬ提出了一个在Ｗｉｎｄｏｗｓ环境下类似ＵＮＩＸ系统Ｖ进程消息通信的消息队列的Ｗｉｎｄｏｗｓ任务间通信的消息队列．应用结果表明，Ｗｉｎｄｏｗｓ任务间使用该消息队列通信接口简单、方式灵活，可实现任意多个任务间的通信．     

一种基于负载信息的机群主结点选择机制

分析了当前机群环境下的负载平衡系统主结点选择机制的弊端，提出了将负载方面的知识引入主结点选择的思想．通过提前估算各结点的负载和使用适当的通信机制，便可以科学地选出负载轻、性能好的结点作为主结点故障后的下一个主结点．该机制可以在不降低机群可用性的基础上更好地平衡系统负载．     

基于蚁群算法的多QoS约束海量数据网格任务调度

针对海量数据计算网格任务调度问题,提出一种多Qos约束网格任务调度蚁群改进算法,优先考虑与数据存储网格结点间数据传输效率高、完成任务概率高的网格计算资源,通过调整蚁群算法中信息素挥发因子和传输导向因子的更新方法来提高算法的收敛速度和全局最优解搜索能力,从而达到调度目标最优.仿真实验结果表明,该算法与QoS-Min-min和QoS-Sufferage等同类算法相比,具有较好的综合性能,特别是在计算数据文件较大时,该算法在收敛速度和全局最优解搜索能力方面有明显的提高.     

平面多轮廓加工路径优化模型及其近似算法

应用一种节点可变的广义旅行商问题，为平面多轮廓加工路径优化问题建模．针对在分层实体制造中，轮廓加工路径的优化必须实时进行、优化计算时间必须小于因路径缩短而节省的加工时间的要求，以及每层加工的轮廓数量通常少于10^2、每条轮廓的节点数可能为10^3的特点，提出一种先用时间复杂度为O(n^2)的最近邻算法，求轮廓原始起点集合的旅行商问题解，然后在O(n)时间内改变每条轮廓的起点，进一步缩短路径长度的2步优化近似算法，从而兼顾了轮廓加工特点和算法实时性的要求．实验统计表明，该算法对路径的优化程度比仅按传统旅行商问题处理时提高了10％以上，且运行时间不超过0．1s。     

Markedness and its Interpretation in Language Use

Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.     

Features of Women's language

Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women＇s language from these perspectives： pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women＇s language, more attention should be paid to language use in social context. What＇s more, the linguistic phenomena in a speaking community can be understood more thoroughly.     

An Analysis of Catherine＇s Character——Wuthering Heights

Wuthering Heights, Emily Bronte＇s only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.     

Lower Paleozoic oil relationships within Williston Basin, Canada

The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.     

低渗透非均质砂岩油藏启动压力梯度研究

理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。     

On Tragic Consciousness In The Works By Ernest Hemingway

As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.     

Design and analysis of generic LBS application developing platform

Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.     

Achieving Unusual States of Matter Under High Pressure

正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that