共查询到20条相似文献，搜索用时 250 毫秒
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在众多社区发现算法中,Attractor算法是一种快速的社区发现算法,具有社区检测准确率高的优点。为解决Attractor算法在距离更新过程中节点对度值相差太大,影响小度节点所属社区判断问题,提出一种优化共同邻居影响的Attractor社区发现算法。该算法在Attractor算法提出的动态距离节点交互模型基础上,考虑节点对两者度值差异,通过在节点对与共同邻居交互模式中增加一个大度节点不利系数,以增加小度节点对邻居的吸引作用。采用LFR基准网络,在不同结构网络上验证改进算法的有效性。实验结果表明,改进算法与Attractor算法相比社区发现准确度更高。 相似文献
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以泰斯公式为基础,将单纯形-混沌优化算法应用于分析抽水试验数据,求解含水层参数函数优化问题。采用具有搜索速度快、局部搜索能力强等优点的单纯形算法与全局搜索能力强的混沌优化算法结合的单纯形-混沌优化算法。数值实验结果表明：单纯形-混沌优化算法可有效地应用于求解含水层参数函数优化问题;待估参数导水系数的初始取值范围、粗搜索次数和混沌序列长度对算法的收敛速度有一定的影响,但不会影响算法的收敛性。 相似文献
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An iterative method was developed for incorporating the well bore boundary into the finite difference model of water flow in variably saturated porous media. Six cases were presented involving groundwater pumping or injection to demonstrate the advantages of the iterative method over the traditional method. For the iterative method, the total flux gradually approached the well discharge and the flux profile was non-uniform. And the iterative method took into account the variation of well bore water table. Compared to the traditional method, the iterative method can simulate the variably saturated flow caused by pumping or injection more realistically. 相似文献
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INTRODUCTION It is recognized that the transfer of soil moistureand heat occur simultaneously and are interrelated.Since the 1950s, many models have been developed,based on two nonisothermal water-heat coupledmodels by Philip and de Vries (1957) and Taylor andLary (1964), respectively. In China, some researcheson modeling coupled transfer of soil moisture andheat have also been conducted on the arid soils innorthern China (Kang et al., 1993; Guo and Li, 1997;Hu et al., 1992; … 相似文献
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李兴芳 《四川职业技术学院学报》2011,21(6):101-103
将动态时间弯曲距离（DTW）的差异矩阵一一对应于点阵,按DTW定义的行走规则对该点阵连线定向,使所对应点阵成为一个有向图,然后使用一个加权技巧对该有向图的边加权后得到一个加权有向图,于是把求DTW的精确计算问题等价地转化为求一个有向图起点到终点的最短路长,从而使图论中求两点间最短路径的方法如目前公认的经典Dijkstra算法均可用于求DTW,因此间接地找到了精确计算DTW的一个新方法. 相似文献
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Simulation models of heat and water transport have not been rigorously tested for the red soils of southern China.Based on the theory of nonisothermal water-heat coupled transfer, a simulation model, programmed in Visual Basic 6.0, was developed to predict the coupled transfer of water and heat in hilly red soil. A series of soil column experiments for soil water and heat transfer, including soil columns with closed and evaporating top ends, were used to test the simulation model. Results showed that in the closed columns, the temporal and spatial distribution of moisture and heat could be very well predicted by the model,while in the evaporating columns, the simulated soil water contents were somewhat different from the observed ones. In the heat flow equation by Taylor and Lary (1964), the effect of soil water evaporation on the heat flow is not involved, which may be the main reason for the differences between simulated and observed results. The predicted temperatures were not in agreement with the observed one with thermal conductivities calculated by de Vries and Wierenga equations, so that it is suggested that Kh, soil heat conductivity, be multiplied by 8.0 for the first 6.5 h and by 1.2 later on. Sensitivity analysis of soil water and heat coefficients showed that the saturated hydraulic conductivity, Ks, and the water diffusivity, D(θ), had great effects on soil water transport; the variation of soil porosity led to the difference of soil thermal properties, and accordingly changed temperature redistribution,which would affect water redistribution. 相似文献
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本文采用单片机技术设计了一套经济实用的监测系统,用于煤矿瓦斯抽放泵站参数的连续监测。利用单片机多机通讯的功能,通过 RDS—1型远程数据收发器将泵站的参数传到调度端进行显示、打印和处理。并对泵站的生产进行必要的管理,为改变目前我国煤矿瓦斯抽放泵站采用人工定时检测的现状。 相似文献
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针对目前多目标跟踪中目标数据关联度量方式的不足,以及Wasserstein度量值衡量概率测度间差异程度的性质,提出基于Wasserstein度量的目标数据关联算法,即利用Wasserstein距离衡量目标外观特征向量之间的相似度,将目标外观特征向量看成一个分布,计算分布之间的 Wasserstein距离,再用Wasserstein距离判断目标是否相似。但是Wasserstein距离表达式比较复杂,难以直接计算,因此通过训练一个深度网络计算Wasserstein距离,并使相同目标特征向量之间Wasserstein距离缩小、不同目标特征向量之间的Wasserstein距离增大;然后,利用目标运动匹配度进一步筛选满足外观匹配度的目标,最终得到最佳目标关联。实验结果表明,该算法能较好地解决多目标跟踪中的漏报问题,与原算法相比,MT提高了6.7%,ML减少了4.9%,FN减少了6 627个。 相似文献
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李建东 《南通师范学院学报》2008,(1):60-64
人的观察视角不同,决定了观察距离的不同。但艺术观审中的“距离”则是一种超实用的审美距离;是日常心理距离向审美距离的跨越。由悲喜剧中的距离审美和假定性心理图式,展开接受美学的距离视野,以此论证艺术与生活中观审距离的生成。接受美学系统阐述了审美距离的生成在于“意义”与“自我感受”的连续性,即审美最佳效果的适中距离,而悲喜剧的艺术接受,最为典型地解释了审美距离的复杂性质;同时,从“生活”中的观审跃升到“艺术”中的观审,也需要心理“距离”的产生,它是两者转化的重要中介。 相似文献
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短距离滑坡规模估算方法研究 总被引：1，自引：0，他引：1
李松 《贵州教育学院学报》2013,(9):49-52
将滑坡分为长滑距滑坡和短滑距滑坡,长滑距滑坡的滑坡体完全滑离原来的位置,而短滑距滑坡体部分滑离原来的位置。依据滑坡地学原理,以四川省古蔺县蔺双路滑坡为例,以二元多项式拟合短滑距滑坡的滑动面和滑坡表面,以SVD拟合滑坡周界的投影面,然后以滑动面和滑坡表面表达式作为被积函数,以滑坡周界投影面表达式作为积分区域,构建积分算法模型,分析滑坡体积算法的实现。计算结果为12．18万m3,而传统的估算结果是7万m3。结果表明,滑坡体积二重积分算法具有更高的精度,能够为滑坡紧急救灾和灾害防治提供更科学的信息支持。 相似文献
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In this study, nine simplified short composite columns consisting of core CFST (concrete filled steel tube) of different diameters and outer reinforced concrete were constructed to study their compressive performance under axial or eccentric compression. The failure mode is characterized by the crush of the outer concrete. The bearing capacity increases at first and then decreases with further increase of the position coefficient. It can be concluded that position coefficient is an important structural parameter that has considerable influences on the ultimate bearing capacity of the composite columns. The outer concrete, steel tubes and longitudinal reinforcement are found to work in a cooperative manner under axial or eccentric compression when the position coefficient is about 0.5. An improved bearing capacity algorithm that takes the position coefficient into account has been proposed based on the experimental and simulation results and current technical specification in China. It has been proven to be precise and safe. 相似文献
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针对实验室现有材料热传导系数测量仪测量精度低,操作性、可视性、人机交互性能差等缺点,研制了一种基于ATmega32单片机为核心处理器,采用DS18B20集成温度传感器对温度信号采集,通过PID算法稳定控制加热盘温度,实现自动数据采集和处理,实时显示温度曲线、良好人机界面功能的材料热传导系数检测仪.介绍了该系统的硬件和软件设计,并通过测量验证了检测仪装置可靠,数据直观准确,精度高,测量时间短,测量方法简单,完全能够满足科研测试和教学实验的要求. 相似文献
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双目立体匹配算法在非接触测量方面的优异表现,使其在机器人的图像识别领域得到了广泛的应用。文章采用局部立体匹配算法中的字符串搜索（BM）算法,将双目摄像头采集的图像对经过立体匹配、校正后得出深度图,由此得出被测物体与摄像头之间的距离,并与实际测量距离进行比较,以检验算法的准确性。在此基础上改变光照强度和测量距离来检测算法的适用性。实验结果表明,BM算法适用于距离小于1.5 m范围内的物体的测量,且该算法对光照强度要求不高,说明BM算法可以应用到双目视觉系统,用于对实际场景的识别。 相似文献
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在视频序列图像中,视频图像分割的主要目的是要在视频序列中分割出运动实体,背景差法能够在实时性要求很高的情况下从一段视频中将当前帧图像跟背景图像作差,然后提取出运动目标,而对差图像进行二值化是关键,自适应阈值方法通过对差图像的直方图进行分析寻找直方图上的一个点,该点到直方图最高点与最低点之间的线段的距离最大,为求该点,本文提出了一种快速算法,以该点对应的灰度值作为阈值,这样运动目标就能够被精确地提取出来. 相似文献
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针对视频中的运动目标离摄像头较近时由于形状的变化而导致目标边界测定不准确的问题,在帧间差分法的基础上,提出了一个求精运动目标边界的算法。先用得到边界值计算目标中心点,再对视频中的运动目标进行运动距离和速度的检测,并在Matlab中进行仿真。实验结果表明,该算法对帧差法的结果进行求精后,得到的运动目标的状态值更接近于实际情况,改进的算法更适合于视频中运动目标形状变化较大的情况下进行运动目标状态的检测。 相似文献
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为了辅助siRNA的设计,从已发表文献中共收集到573个siRNA的实验数据,使用基于统计学习理论的支持向量机(SVM)方法,提取了siRNA序列的碱基对关联性(BBC)特征,然后使用十倍交叉验证方法,对siRNA沉默目标基因的效率进行了预测.结果表明,基于支持向量机,选用多项式核作为核函数的算法具有最高的AUC值(0.73,ROC曲线图)和最高的r值(0.43,Pearson相关系数分析),优于以前基于打分的算法.结果说明,在以后的siRNA的设计中应该更多关注碱基之间的关联信息. 相似文献
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以唐山市区为例,介绍了土壤土质特性与建设土壤源热泵系统适宜性的关系,通过试验测定了土壤层温度的变化,给出了土壤导热系数的确定方法,并模拟分析了土壤层不同的初始温度和土壤导热系数对地埋管换热器传热的影响。 相似文献
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李政 《桂林师范高等专科学校学报》2007,21(2):129-131
在求解最短路径时经常使用经典的Dijkstra算法,但在实际应用中在计算最短路径长度时需要进行大量的数据比较,而当图中两顶点之间的距离是∞时,是没有必要进行比较的。本文从存储结构上讨论如何对Dijkstra算法进行优化,尽量减少数据比较次数。 相似文献
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We propose a novel kind of compound permanent magnet synchronous machine (CPMSM), which is applicable in low-speed and high-torque situations. We first explain the structure of the CPMSM. Based on theoretically deducing the calculation formulae of the CPMSM electromagnetic parameters, we analyze the operating characteristics of the CPMSM, and obtain the power-angle curves and working curves. The no-load magnetic field distribution and the cogging torque are analyzed by applying the finite element method of three-dimensional (3D) magnetic fields, to determine the no-load leakage coefficient and the wave0form of the cogging torque. Furthermore, the optimal parameters of the permanent magnet for reducing the cogging torque are determined. An important application target of the CPMSM is in direct-drive pumping units. We have installed and tested a directdrive pumping unit in an existing oil well. Test results show that the power consumption of the direct-drive pumping unit driven by CPMSM is 6 1. 1% of that of the beam-pumping unit, and that the floor space and weight are only 50% of those of a beam-pumping unit. The noise output does not exceed 58 dB in a range of 1 m around the machine when the machine is 1.5 m from the ground. 相似文献