基于统计分析学的城市车道占用数学模型

通过对参考文献1的观察统计,讨论在事故发生到结束这一段时间内,横截面通行力的变化情况,对占用车道不同导致实际通行力变化情况.并且建立排队车辆长度和实际通行力、时间、上游车流量之间的数学模型.

统计实验方法浅析

随着计算机的产生 ,许多的实际问题都借用计算机来解决 ,从中产生了计算方法 ,概率统计法就是其中的一种。本文把握概率统计法的基本思想是 :根据所要解决的问题设计模型 ,使这个模型的某个模型恰好就是所要计算的量 ,而这个特征值可以通过实验方法求出。本文针对不同形式的随机变量设计模型 ,进行随机变量的模拟 。

基于统计方法的家用电器行为模型

随着城镇化进程发展与居民生活水平提升,城镇住宅能耗总量提升。与此相关,家用电器能耗占比增加。实际上,不同住户之间,住宅实际用能差异很大,分析其原因,住户的行为差异是巨大的实际能耗差异的重要原因之一。用能总量提升的背景下,需求侧响应尤为重要,要求对小时间步长的负荷特性有更加深入的研究。因此住宅逐时功率负荷特性,尤其是家用电器的逐时负荷特性备受关注,要求模型具备三个方面的特性:住户用能模式随机性,模型可推广性与验证的完备性。本文提出一种基于单户家庭单个家用电器能耗数据的分析方法与家用电器行为模型的构建思路,通过模型构建,实现家用电器能耗与逐时负荷特性的再现。本文以电视机作为研究案例,开展数据分析与模型构建,同时将提出的模型,与马尔科夫模型效果进行对比,经过模型检验,验证了提出模型的准确性与可靠性。文章所提出模型,对于单户住宅乃至区域住宅的用能分析,具有工程实际应用的可推广性。

泰语人名、地名、机构名实体识别研究

泰语命名实体识别是把泰语文本中的人名、地名、机构名等识别出来。由于泰语构词方法和语法规则复杂,针对这一问题,将泰语命名实体识别任务转化为对泰语句子中的词汇序列进行标记。结合泰语语言特点,选择合适的泰语上下文特征,分别使用隐马尔科夫模型和条件随机场模型在泰语实体识别训练语料上进行了模型构建,并在测试语料上对所构建的序列标注模型进行了实验验证。实验结果表明使用隐马尔科夫模型和条件随机场模型进行泰语人名、地名、机构名实体识别是可行的,并取得了较好的效果。

空间目标的光散射研究

从太阳辐射理论出发,介绍了漫反射目标的地面光照度计算公式。在高斯随机面元统计散射模型的基础上,提出了目标表面为随机粗糙平板面的空间目标散射太阳光产生地面光照度的散射计算模型。利用该模型计算了风云一号卫星的地面光照度,并与把卫星表面看作朗伯表面计算得到的地面光照度进行了比较。结果表明,把卫星表面看作漫散射体得到的地面照度值要比把卫星表面看作随机粗糙表面得到的地面照度值大。

Deterministic and Stochastic Simulators for Non-Isotropic V2V-MIMO Wideband Channels

In this paper, we consider a novel two-dimensional(2D) geometry-based stochastic model(GBSM) for multiple-input multiple-output(MIMO) vehicle-to-vehicle(V2V) wideband fading channels. The proposed model employs the combination of a two-ring model and a multiple confocal ellipses model, where the signal is sum of the line-of-sight(Lo S) component, single-bounced(SB) rays, and double-bounced(DB) rays. Based on the reference model, we derive some expressions of channel statistical properties, including space-time correlation function(STCF), Doppler spectral power density(DPSD), envelope level crossing rate(LCR) and average fade duration(AFD). In addition, corresponding deterministic and stochastic simulation models are developed based on the reference model. Moreover, we compare the statistical properties of the reference model and the two simulation models in different scenarios and investigate the impact of different vehicular traffic densities(VTDs) on the channel statistical properties of the proposed model. Finally, the great agreement between simulation models and the reference model demonstrates not only the utility of simulation models, but also the correctness of theoretical derivations and simulations.

Statistical Characteristics of the Received Signal for Stochastic Surface Models

This paper describes the stochastic model of the scattered electromagnetic field.Unlike common_used functional_determined models the proposed is characterised by amplitude/phase fluctuation of the received signal.This paper derives the statistical characteristic of the input signal and describes algorithm for its estimation in post_processing and real_time processing modes.Achieved characteristics allow the mapping and estimation of the surface models more accurate,moreover,such processing increase space resolution of synthetic aperture radar.

An efficient latent variable optimization approach with stochastic constraints for complex industrial process

For complex chemical processes,process optimization is usually performed on causal models from first principle models.When the mechanism models cannot be obtained easily,restricted model built by process data is used for dynamic process optimization.A new strategy is proposed for complex process optimization,in which latent variables are used as decision variables and statistics is used to describe constraints.As the constraint condition will be more complex by projecting the original variable to latent space,Hotelling T^2 statistics is introduced for constraint formulation in latent space.In this way,the constraint is simplified when the optimization is solved in low-dimensional space of latent variable.The validity of the methodology is illustrated in pH-level optimal control process and practical polypropylene grade transition process.

New model for deducing directional extrema based on multivariate extremum statistical theory

The parameters of principal and directional extrema in a marine environment are important in marine engineering design, especially for appropriate construction of oceanic platforms and other structures. When designing wave walls and break water structures, the orientation of the breakwater or seawall depends mainly on the direction of the strongest waves. However, the strength of the breakwater and the elevation of the seawall depend on the magnitude of the biggest wave height of the strongest waves. Thus, identification of directional extrema plays an important role in the design of wave factors. When calculating the directional extremum, different materials may require different specific computational methods, yet few theoretical studies have been conducted in this field of research. Based on multivariate extremnm statistical theory, this paper utilizes a discrete random variable to build a joint probability model compounded by a discrete random variable and a multivariate continuous random variable. Furthermore, this paper provides the first investigation on the theories and methodologies to deduce wave directional extrema. The results provide tools for both creating the calculation method of the directional extremum value and providing the rational directional extremum parameters for marine engineering design.

北京市湿地生态系统非使用价值

非使用价值是生态系统的内在属性,科学合理地评价该价值对生态资源管理和合理配置具有重要意义。本文运用条件价值法(CVM法),通过调查北京市居民的支付意愿,定量评估北京市湿地生态系统的非使用价值。采用分区方式,根据分区的人口数确定发放调查问卷的数量,于2008年10月分别在城区和郊区随机发放600份和300份调查问卷。采用修正的单纯随机抽样统计分析模型,提出以家庭作为抽样统计单位的思想,分别对两分区反馈回的调查问卷进行统计分析,得到北京市湿地生态系统非使用价值的评估总值为每年2.65亿元,其中城区为每年1.99亿元,郊区为每年0.66亿元。分析社会特征与支付意愿和WTP值的相关性得出:教育程度和年龄是影响支付意愿和WTP值的主要因素;月收入在城区样本中对支付意愿和WTP值的影响很小,而在郊区样本中的影响则相当显著;性别对支付意愿和WTP值的影响不大。

大都市边缘区旅游产业链动态演化研究——以西安临潼区为例

以西安临潼区为例,利用随机生灭理论与有向图理论结合,对其旅游产业链的动态演化过程进行了分析,并通过建立马尔科夫状态转移过程动态随机统计模型,同时结合产业经济漏损的约束条件,对西安临潼区旅游产业链的动态演化进行了模拟分析。结果表明:临潼区旅游产业链的动态延伸将成为区域经济发展、改善城市社会形态的重要增长点;其旅游产业链也将会在其动态演化中逐步得到完善。