城市快速交通线项目票价预测模型

建立城市快速交通线项目票价预测模型 ,采用历史趋势外推法预测运量 ,制定合理的票价 ,为乘客选择交通工具提供依据 .     

Long-Term Strength Criteria for Some Polymer Materials under a Plane Stress State

The problem of the choice and experimental justification of long-term failure criteria for isotropic polymer materials in creep under a plane stress state is considered. The criteria are defined by a linear two-parameter interpolation relating two stress-tensor invariants which limit the interpolation range with respect to the conditions of viscous and brittle failure and take into account the signs of principal stresses. The base experiment for determining material constants includes standard tests on long-term strength in uniaxial tension and a test on long-term strength under a plane stress state. The failure criteria have been approved in constructing unified long-term strength diagrams for thin-walled tubular specimens made of rigid polyvinylchloride and high-density polyethylene under the action of internal pressure, pressure with axial tension, torsion, and axial tension with torsion.     

A METHOD FOR PREDICTING HARBOR SEAL (PHOCA VITULINA) HAULOUT AND MONITORING LONG‐TERM POPULATION TRENDS WITHOUT TELEMETRY

Monitoring population trends in harbor seals (Phoca vitulina) generally involves two steps: (i) a census obtained from aerial surveys of haul‐out sites, and (ii) an upward correction based on the proportion of seals hauled out as estimated from a sample of telemetry‐tagged seals. Here we present a mathematical method for obtaining site‐specific correction factors without telemetry. The method also determines site‐specific environmental factors associated with haulout and provides algebraic equations that predict diurnal haul‐out numbers and correction factors as functions of these variables. We applied the method at a haul‐out site on Protection Island, Washington, USA. The haul‐out model and correction factor model were functions of tide height, current velocity, and time of day, and the haul‐out model explained 46% of the observed variability in diurnal haul‐out dynamics. Although the particular models are site‐specific, the general model and methods are portable. A suite of such models for haul‐out sites of a regional stock would allow managers to monitor long‐term population trends without telemetry.     

财政补贴政策与长期护理保险市场演化

财政补贴政策是政府矫正市场失灵,驱动长期护理保险市场高质量演化发展的重要手段。本文基于多主体仿真模型,考察不同补贴政策驱动长期护理保险市场演化的过程。研究发现:实行产品创新补贴政策时,可以形成健康有序的长期护理保险市场竞争格局;实行经营性补贴政策时,长期护理保险市场容易演化成垄断市场。保费补贴政策能够扩大需求规模,且差异化的保费补贴政策能够更加有效地激励需求空间的大幅增长。     

Semiparametric modeling of the spatiotemporal trends in natural gas consumption: Methodology,results, and consequences

Household consumption of natural gas is usually considered to be quite stable as cooking, space, and water heating belong to basic needs. The improvement of technologies together with possibilities of switching to alternative sources can, however, lead to a decreasing consumption trend. Knowing more about such trend, especially of its spatial distribution, can be useful for strategic planning. In this paper, we describe a general statistical methodology allowing to study the spatiotemporal behavior of consumption. It is based on semiparametric modeling. Formalized error and sensitivity analyses are part of the methodology. Presented methods are illustrated on large‐scale data from the Czech Republic.     

Nonparametric estimation of trend for stochastic differential equations driven by mixed fractional Brownian motion

We discuss nonparametric estimation of trend coefficient in models governed by a stochastic differential equation driven by a mixed fractional Brownian motion with small noise.     

考虑支承的大跨度索膜结构整体分析与设计

基于修正的拉格朗日法,建立非线性有限元平衡方程,介绍了空间梁单元非线性刚度矩阵。针对此类结构在形态分析及设计中的难点问题,提出利用定力单元、定形单元和微调单元建立数值模型。采用AutoCAD二次开发工具ObjectARX编制有限元软件,能够进行考虑支承的大跨度索膜结构整体分析与设计。以芜湖体育场为工程背景,进行了形态分析和长期荷载组合下的反应。计算结果表明,本文所提方法和有限元软件显著地提高了设计工作的效率,并能准确地获得满足设计要求的结构初始形态及受力分析数据,便于实际工程的设计应用。     

非等间隔阶跃灰色模型在滑油光谱分析中的应用

针对非等间隔、具有阶跃趋势的原始数据序列建立了非等间隔阶跃灰色模型 ,模型参数的辨识采用了非线性最小二乘估计的Levenberg Marquardt算法。将所建模型用于 16V2 80ZJA型机车柴油机滑油的光谱分析数据的建模 ,得到了较高的拟合精度 ,尤其在阶跃点附近 ,大大改善了拟合精度。利用模型参数对换油后的测试数据进行修正 ,有利于提高光谱分析的准确度和可靠性。     

五元联系数在学生成绩发展趋势分析中的应用

在利用集对分析中的五元联系数描述给定范围内学生成绩为优、良、中、及格和差五类中各类所占的比例时,该五元联系数同时隐含着该批学生成绩的当前态势和潜在的发展趋势,通过偏联系数计算,可以揭示出其中潜在着的发展趋势.从而为更好地开展下一阶段教育提供了客观依据.     

火灾发生的周期性规律及其在火灾非线性组合预测模型中应用

研究火灾发生规律及发展趋势,具有实用价值.分析历年中国火灾统计数据,发现中国火灾的发生规律同时具有增长趋势性和周期波动性特征:①中国火灾从90年代开始大幅度增加,在2002年达到最大,然后逐年缓慢下降;②每年12个月呈正弦函数波动,周期为12,1、2月发生起数最大,8、9月最小.借助于M ATLAB软件,根据2000-2006年中国火灾统计数据,建立火灾的月发生起数的非线性周期性组合预测模型,预测值与实际值的平均相对误差小于0.07.研究结论为消防研究、消防部门决策提供科学依据.