投资项目经济评价指标的研究

本文在探讨“平坦”模糊数及其运算的基础上,提出模糊内部收益率的概念;并利用Prade与Dubois提出的比较两个模糊数大小的指标,给出“近似相等”的概念;从而给“模糊内部收益率”的计算提供了一个方法。     

桥梁对河流阻水影响的一个综合判别指标

针对桥梁对河流的阻水影响问题,基于河流能量观点提出了考虑河流能量与桥梁阻水比双因素的综合判别指标η,应用其讨论了山区河流和平原区河流修建桥梁对河流的阻水影响。结果表明:综合判别指标η可以有效地区分相同桥墩布置形式桥梁对不同类型河流的阻水影响;综合判别指标η可以指导桥墩在河流中的合理布置,有效减小桥梁对河流的阻水影响,与桥梁阻水比、单宽流量等指标在指导桥墩合理布置方面起到相同效果。该研究成果在一定程度上弥补了一般桥梁阻水比指标的不足。     

Temporal and spatial dynamics of surface run‐off from Lake Basaka catchment (Ethiopia) using SCS‐CN model coupled with remote sensing and GIS

The Lake Basaka catchment (Ethiopia) has undergone a significant land use–land cover (LULC) change and lake level rise over the past five decades. Significant quantities of water and sediment flow annually into the lake through erosion processes. An appropriate method of estimating the surface run‐off from such ungauged and dynamic catchment is extremely important for delineating sensitive areas (based on run‐off responses) to be protected and for development of suitable measures to reduce run‐off and associated soil loss. Reliable prediction of run‐off, however, is very difficult and time‐consuming for catchments such as that of Lake Basaka. The present study estimated the dynamics of surface (direct) run‐off using the NRCS‐CN model in ArcGIS, assisted by remote sensing and ancillary data. The results indicated the Lake Basaka catchment experienced significant temporal and spatial variability in its run‐off responses, depending on the rainfall (amount and distribution) pattern and LULC changes. A significant run‐off increase occurred after 1973, consistent with significant LULC changes and lake level increments occurring after that period. A reduced vegetation cover also resulted in increased run‐off coefficient of the lake catchment from 0.11 in the 1970s to 0.23 in the 2000s, indicating the important need to consider possible future LULC evolution when forecasting the lake catchment run‐off behaviour.     

基于数据分布的快速灰关联分析

从灰关联分析中最核心的灰关联度构造及相应的挖掘算法出发,结合正态分布的普适性,提出了一种体现数据分布特点的正态灰数,并给出了相应的灰度及灰关联度计算方法。在此基础上,构建了一种多粒度无监督的快速灰聚类方法,无需先验知识即可完成自动聚类。通过实验验证了本文方法的有效性,为大数据下灰关联分析的进一步发展提供了新思路。     

负相依随机变量序列延迟平均的一类极限定理

研究负相依随机变量序列延迟和的一类强大数定理以及强收敛性.利用随机变量截尾方法建立负相依随机变量的概率不等式和矩不等式,在矩条件E(exp{t|X1|})＜∞(p＞1)下,获得了负相依随机变量延迟平均的强大数定理、完全收敛性以及(log n)-p∑n+1[log'n]k=n+1Xk的上、下界,推广了若干经典结果.     

社交网络的有效信息量研究：基于节点强度的分析

为了研究社交网络中的有效信息量,结合节点度分布和节点强度的概念,提出了一种社交网络中有效信息量的分析方法.首先,基于邓巴数字的理论,提出有效信息量函数,并结合节点强度来描述社交网络节点的有效信息量的变化趋势.其次,通过对Twitter社交图表的研究,得到社交网络的节点度分布函数,并结合有效信息量函数,对给定的社交网络有效信息量进行分析和量化.最后,分析社交网络系统有效信息量的局限和特征,使社交网络的用户能更好地获得自己所需要的信息.研究证明:现在社交网络中的邓巴数字处于[210,220],已经超出了150定律,同时,社交网络系统有效信息量也趋于一个特定的值.     

Introduce Dissipation for Cylindrical Structures with Moon-Pool of Restricted Entrances

In order to consider the viscous effect,the introduction of a parametric dissipation and new results are realized by applying the new formulation combining and dynamic conditions over the free-surface with viscous terms. The dispersion equation is then modified by assuming an additional term in the boundary condition at the free-surface and wave-number becomes complex number with a small imaginary part which ensures the decay of wave amplitudes. The comparisons of numerical results and model test measurement on wave elevation at the moon-pool center is obtained both for the peak period and for the amplitude at resonance by choosing an appropriated dissipation coefficient. The results show that the introduce dissipation is not only effective but also reliable to provide realistic predictions.     

模糊数度量的单值函数表示

基于一个具体的三角模糊数作为结构元,给出了模糊数与定义于[-1,1]上的单调递增有界且上半连续的函数构成的集合之间的一一对应关系,从而得到了模糊数的单值函数表示。在上述表示基础上,给出了模糊数空间上的各种度量如上确界度量、Lp度量、sendograph度量的单值函数表现,从而将对模糊数的度量(拓扑)性质的研究完全转化为对普通单调递增有界且上半连续的函数空间中相应性质的研究。     

清晰数的比较

在清晰数的四则运算的基础上,给出了清晰数心的概念,继而定义了清晰数的大小关系,这样就可以进行清晰数的比较,为以后的研究奠定了基础。     

基于群组层次分析法的管制员绩效考核

基于FAA和EUROCONTROL对管制员的工作要求,结合一线管制工作实际建立了管制员绩效考核指标体系,应用基于三角模糊数的群组层次分析法对指标体系权重进行确定,克服了传统主、客观分析法的缺陷,并通过在一线单位的应用证明了算法的可行性。