基于影响因素分析的公共自行车系统可持续发展研究——以呼和浩特市为例

自行车是绿色出行的主要交通方式之一。我国许多城市的公共自行车系统存在调度不合理、硬件设施不完善造成的难以可持续发展问题。因此,在深入剖析公共自行车系统影响因素的基础上,研究其可持续发展问题。首先,基于问卷调查数据,建立Logit模型,定量描述各因素对居民选择自行车出行的影响;接着对系统的效益进行分析与优化;最终基于影响因素给出系统可持续发展的相关建议。研究表明,出行距离、离单车或站点距离、租借方式、是否有自行车专用道、是否保有机动车对租借概率具有显著影响;公共自行车系统应借鉴共享单车运营模式,向有电子围栏、扫码租借和刷卡租借共存的新型自行车系统发展。研究结果可帮助有关部门有效掌握新形势下自行车选择行为的显著性影响因素,为提高公共自行车的利用率和可持续发展提供决策依据。     

基于大数据的公共自行车运营分析及调度模型

为解决公共自行车系统在交通高峰时间段自行车借还困难问题,提升公共自行车系统的运行效率和用户 满意度,以某市的现有公共自行车系统运营情况为研究对象,通过大数据归纳了公共自行车系统的借用和返回 规律,分析了公共自行车的运行特点,研究公共自行车的时间特性和周转特性,并且为调度模型的建立提供了 数据基础,最后通过改进蚁群算法建立了较好的公共自行车调度模型。实验结果表明,建立的静态调度行驶路 径优化模型得到了最优调度行驶路径,从而使高峰时间段自行车借还困难问题得到了有效解决,减少了调度所 需时间并提高了工作效率。     

佛山市禅城区公共自行车系统运营的优化

首先收集了公共自行车的每个站点在30 d内的使用数据,然后应用Excel和SPSS等统计软件对使用数据进行统计、分析,得到公共自行车服务系统各个站点的运行规律、借车人借还车规律和高峰日系统的具体运行规律,分析了佛山市禅城区公共自行车的运营现状,最后在此基础上针对公共自行车运营的服务方式、租赁站点规划及经营中不足的方面提出优化建议和方案。     

基于双层规划的共享自行车区域投放规划模型

共享自行车逐渐成为我国居民短距离出行的主要方式之一,但共享自行车的投放与用户需求不平衡的问题仍待解决。针对共享自行车的投放位置和规模的问题,提出了共享自行车区域投放和虚拟站点的概念,构建了共享自行车网络系统,建立了共享自行车区域投放双层规划模型。上层模型以系统用户总的出行成本最小为目标,考虑了企业、用户等约束条件,为系统最优模型;下层模型为网络用户均衡模型,并提出了混合遗传算法与粒子群算法求解该模型。最后,用某中等城市共享自行车出行数据进行分析,验证模型与算法的实用性。结果表明,该模型能同时确定投放区域虚拟站点的选址及规模,为共享自行车的投放提供了科学合理的依据。     

半开放式的多车场移动充电车路径优化

为解决移动充电平台投入运营成本高的问题,考虑应急服务点时间窗、流量平衡及充电车里程限制等约束,建立包括移动充电车为应急服务点提供充电服务的车辆启动成本、行驶成本和违反应急服务点的时间窗惩罚成本三者总和最小的混合整数非线性规划模型,通过分支定界法和遗传算法研究了半开放式的多车场移动充电车路径优化问题。结果表明：对半开放式的多车场移动充电车路径优化问题进行10次求解,GAP均值为1.22%,说明遗传算法具有良好的稳定性;与单车场独立服务模式对比分析,半开放式多车场联合服务可为移动充电车提供更多路径选择,减少充电车行驶里程,降低平台运营成本;对比顾客点集中分布情形,在顾客点随机分布和混合分布情形下,移动充电平台的成本节约效果更为显著。     

公共自行车出行质量实证研究

以上海闵行区公共自行车系统为例,调查获得人们在公共自行车系统实施之后出行方式的转换,采用离散选择模型解释这种转换下的决策机制.发现公共自行车特征、出行时耗以及服务点可达性是出行方式转换的重要影响要素.应用模型发现公共自行车使用者的出行质量显著提升,而出行总质量提升最多的集中于较为功利性的出行目的.转换自公交方式的出行获得质量提升最多,转换自小汽车的出行质量提升最少.预估并比较服务站点密度增加和公共电动自行车两种服务方式的竞争力发现,后者对出行质量提升的效果明显高于前者.     

旅客视角下基于时变的多模式交通网络出行路径

城市多模式交通出行路径决策会受到城市公共交通发班时刻表及交通网络时变特性影响。本文考虑这两个影响因素,研究了换乘次数、出行时间、步行距离等约束条件限制下以实际出行成本最少为优化目标的城市多模式交通出行路径决策问题。由于该问题为NP难问题,本文提出了基于遗传算法的四种求解策略。数值算例表明四种求解策略均有效,其中,变异概率随迭代次数调整的多种群遗传算法求解策略计算效率最高。     

自行车流影响下的网络交通流均衡分析

使用实际可变旅行时间风险度量方法,考虑了旅行时间长短与旅行时间波动性两方面因素对路径选择行为的影响,并建立了存在自行车流的混合交通流网络交通平衡分析模型.该模型能恰当地描述机动车驾驶者对劣化出行路段的筛选行为,再现网络交通流趋于实际可变旅行时间风险度量下的交通平衡过程.实例研究表明：通过单幅道路自行车与机动车使用空间组织优化,在保障自行车交通出行者安全的同时,能提高25%以上的交通效率.     

基于GWR的建成环境对公共自行车出行模式的影响分析

为分析建成环境对公共自行车出行模式的影响，文章结合公共自行车运营数据和建成环境数据，以公共自行车站点为中心建立缓冲区并提取缓冲区内兴趣点(point of interest, POI),在考虑POI规模的基础上划分站点类型；根据站点类型对出行起讫点(origin-destination, OD)分类，以OD类型确定公共自行车出行模式，使用地理加权回归(geographically weighted regression, GWR)模型，分析建成环境对公共自行车出行模式的影响；以昆明市为例进行实证分析。结果表明：昆明市公共自行车出行模式可划分为16种，OD皆为住宅主导型和公司(企业)主导型站点的出行模式约占69.26%;建成环境对不同出行模式的影响效应存在差异；土地利用混合度是公共自行车出行模式的主要影响因素。研究结果可为公共自行车布局优化及运营管理提供参考。     

车辆完好是经营城市公共自行车的基本要求

正城市公共自行车交通指的是供公众免费或以较低的费用使用,停放在公共场所、并能实现各服务点之间统一租借和归还的自行车交通方式。这种慢行交通方式是对城市公共交通系统的有效补充,它减少了我们所生活城市的交通拥堵,给我们带来方便与快捷。只有车辆完好才能满足经营城市公共自行车的基本要求。每位骑车人都盼望所骑行的自行车是完好的,希望车辆完好率能达到城市公共自行车运营的基本要求。城市公共自行车完好率是指被抽检     

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.     

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     

Call for Papers

<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with