An experimental analysis on the turnover time of railway freight transportation based on the impact strength of factors

Based on the factors impact strength model(FISM), we studied on calculation formulas of influence strength and key elements of FISM, and analyzed the turnover time of railway freight transportation of China. The results show that wagon transfer time is the most critical factor among the three subjective factors of wagons turnover time. The FISM based analysis of wagon transfer time show that the wagon turnover time is significantly correlated with transit time with resorting. Among the seven factors of detention time of transit time with resorting, the time of waiting to departing, converging, and waiting to break-up are key factors, while the time of make-up, break-up, arrival and departure are general factors. We carried out one empirical research based on the data of Baoji East Railway Station in 2015. The results of empirical research and FISM are consistent completely.

LONG-DISTANCE-RELAYED WATER VAPOR TRANSPORT EAST OF TIBETAN PLATEAU AND ITS IMPACTS

This paper attempts to reveal a long-distance-relayed water vapor transport(LRWVT) east of Tibetan Plateau and its impacts. The results show that from August to October, east of Tibetan Plateau, there exists a unique LRWVT,and the water vapor from the South China Sea and the western Pacific can affect the Sichuan Basin, Northwest China and other Chinese regions far from the tropical sea through this way. From August to October, the precipitation of the region east of the Plateau is closely linked both in the intra-annual and inter-annual variations, and the LRWVT from the South China Sea and the western Pacific is an important connection mechanism. The large-scale circulation background of the LRWVT impacting the precipitation of the region east of the Plateau is as follows: At high levels,the South Asian High is generally stronger than normal and significantly enhances with its northward advance and eastward extension over the region east of the Plateau. At mid-level, a broad low pressure trough is over Lake Balkhash and its surroundings, and the Western Pacific Subtropical High(WPSH) is northward and westward located, and the western part of Sichuan Basin and the eastern part of Northwest China are located in the west and northwest edge of WPSH.

The Impacts of Urban Land Use on Urban Transport System in High-Densely Developed City-a Case Study of Guangzhou

Recently the study on the mutual relationship between urban transport and land use has been one of the hot subjects in the fields of urban geography, urban transport planning and urban planning. This paper tires to carry out some methods, such as multi-analysis statistics method, to specify the impacts of urban land use on urban transport system. Firstly, the choice of urban transport road network affected by the characters of urban land use layout is discussed. Secondly, the promotion of urban public transportation affected by high-density concentrated land use pattern is demonstrated. Thirdly, the impacts of urban city-size on transport system structure characters are expatiated. Finally, the impacts of urban master planning in Guangzhou on the layout of transport system are illustrated.

超临界CO_(2)管道止裂韧性预测模型研究

碳中和目标下,超临界态CO_(2)管道输送已成为碳捕集利用与封存(CCUS)技术发展的必然趋势。然而,目前超临界CO_(2)管道止裂控制体系尚未构建,管材止裂韧性难以预测,成为限制其广泛应用的瓶颈问题之一。针对该问题,通过归纳国内外相关文献及规范标准,对超临界CO_(2)管道止裂控制研究进展及最新标准体系进行了简要综述;在系统收集已开展CO_(2)管道全尺寸爆破试验信息及数据的基础上,对现有止裂韧性预测模型适用性进行了讨论,由此确定了CO_(2)管道止裂韧性预测模型修正形式,并对不同模型适用范围及预测结果进行了讨论。研究结果表明,建立的修正模型解决了传统止裂预测模型过于激进的问题,同时降低了DNV推荐方法的保守性。建议将修正模型与DNN预测方法相结合,以使管材韧性值处于止裂区域;同时开展高效准确的CO_(2)管道裂纹动态扩展数值模拟。所得结果可为我国CO_(2)管道止裂设计提供指导。

气流对氢燃料电池气体扩散层输水性影响分析

为研究气流对扩散层输水性的影响,构建二维模型表征扩散层纤维结构特征;联合VOF(Volume of Fluid)方法、N-S方程、Darcy定律及毛细压力方程,建立多孔介质内气液控制方程,跟踪气液流动界面,分析气流压力、温度和输入模式与不同孔隙率扩散层水输运状态的关系,阐明气流与孔隙结构耦合作用对扩散层水分布的影响机理。结果表明:扩散层内气流分布直接影响水的输运,而气流状态与扩散层孔隙结构特征密切相关;增大气体输入间隔对于增进扩散层排水效果显著。该研究对于提升扩散层的输水性具有借鉴意义。

考虑环境因素的货运航线网络优化设计

针对传统货运航线网络设计中仅考虑经济目标而忽视环境影响的问题,在绿色民航的背景下,提出一种综合考虑经济目标和环境影响的货运航线网络优化方法。基于多分配严格枢纽航线网络,以经济成本、CO_(2)、CO和NO_(x)排放量最小为目标,构建相应的数学模型。采用线性加权和法与分支定界法结合案例求解。结果显示,不同优化目标下的航线网络结构存在一定差异,难以同时达到最优。与仅考虑经济成本的求解方案相比,采用本文的综合求解方案,能够实现经济效益和环境效益间的较好均衡。

鱼类麻醉保活运输研究进展

为了解麻醉保活技术在活鱼运输中的应用和最新研究进展,对活鱼运输过程中麻醉剂的种类、麻醉保活效果的影响因素、麻醉对鱼体生理生化及组织结构的影响进行了总结。

一种基于防振球的光刻机金属包装运输设计

为解决目前光刻机包装运输中采用木箱和橡胶减振球的结构存在使用周期短,成本高的问题,我们设计了一种基于防振球的光刻机金属运输底板,防振球相比橡胶减振器具有较为明显的成本优势,使金属运输底板设计过程中采用了较为经济的设计方案;同时,我们结合光刻机的特性,通过对基于防振球的金属运输底板静力工况、运输冲击工况及海运中的冲击、摇摆、倾覆工况进行了分析计算,计算结果得出了基于防振球的金属运输底板可用于光刻机的结论。综上看出:一是采用基于防振球的金属运输底板替代现有的木箱包装运输方案,解决了木质包装箱使用周期短的问题,成本高的问题;二是通过对海运工况评估解决了海外光刻机只能采用空运的唯一运输方式,使光刻机运输形式多了一种选择,降低了运输成本。

高铁发展对民航运输的影响及其应对措施研究

近年来高铁逐渐成为人们出行的首选,高铁的迅猛发展也对民航运输产生了一定的影响,特别是在短途航线上。基于此,航空公司不得不重新审视自身的运营模式和市场竞争策略,寻求应对之道。本篇文章研究高铁发展对民航运输的影响,并提出相应的应对措施,以引导航空公司应对新的市场环境,实现与高铁共同发展的目标。

抚河流域极端降水变化及其对输沙量的影响

本文基于抚河流域1960—2018年逐日降水和输沙量的历史数据,分析极端降水变化规律及其对输沙量的影响。结果表明:抚河流域8种极端降水指数均呈增长趋势;8种极端降水指数空间上总体呈现“北高南低”“东高西低”和“南高北低”三种格局;抚河输沙量呈不显著减小趋势(Z=-1.48),人类活动是流域输沙量减小的主导因素;极端降水指数和输沙量呈正相关,总体上存在1年、4年、16年的周期性显著共振关系。

马鞍山某公司制氢站更新改造工程项目地下水环境影响评价

为改进生产工艺、扩大产能规模,马鞍山某公司拟在原制氢区域开展制氢站更新改造工程项目。该项目属石化类建设工程,为准确评估其在建设、生产运营等阶段对地下水环境产生的影响,需在建设区及周边影响区开展专项的制氢站更新改造工程项目地下水环境影响评价。通过收集研究区内水工环地质资料合理概化得到水文地质模型,在此基础上逐步构建了地下水流数值模型,并依据已有的水位数据进行了模型的识别校正与验证。采用验证后的数值模型对评价区内污染物的运移情况作了预测分析和评价,结果表明:(1)正常状况下,预测场区内各泄漏点的污染物及扩散对下游地下水环境影响小;(2)非正常状况下,废水收集池渗漏和制氢装置区泄漏会导致污染物产生运移,对周边地下水造成一定影响。本项目地下水环境影响评价较为系统,有助于建设方识别污染源,了解在不同情景下污染物运移对地下水环境的影响程度与影响范围,为后期的综合防治提供了具体方向。

Transportation Development Transition in China

Scientific development is an invaluable asset to a country.Policies and development modes should be carried out based on scientific findings not only in industry,but also in transportation infrastructure construction.Building an integrated transportation system,which is in line with the national requirements of China and supports sustainable socio-economic development,is a key strategic issue related to building a moderately prosperous society and achieving realistic goals of a medium-level developed country.Based on a systematic review of the advances in China's transportation infrastructure over the last 60 years,this paper explores the main drivers of transportation development,including national policy,transportation structure,investment efficiency,and technological innovation.Analysis shows that China's comprehensive transportation infrastructure construction since 1949 can be divided into five stages initiated by these drivers,which correspond to four transition modes:policy transition,structural transition,efficiency transition,and technology transition.The transition path of China's transportation development shows that the dominant factors have changed,and the interval for each transition has shortened.With the implementation of the '12th Five-Year Plan',China's transportation infrastructure construction is showing some new characteristics and facing a new development transition.Finally,this paper analyzes the trends in transportation development in China and concludes that technological innovation will be the main driving force to increase the transportation supply and service area in the future.

区域交通评估中的交通设施用地匹配关系研究

交通设施用地的匹配关系是区域交通评估工作的重要组成部分.以城市道路用地、地面公共交通场站及社会停车场3类交通设施用地为例,探讨了各类交通设施用地的核心要求与匹配关系.结果表明,在区域交通评估工作中,对城市道路用地的核心要求为空间布局和路网密度,地面公共交通场站及社会停车场用地的核心要求为空间布局和用地面积,通过实际案例对交通设施用地匹配可能存在的典型问题提出了改善建议.

综合交通运输服务指数构建与应用研究

交通运输作为国民经济和社会发展的“先行官”,是经济社会发展的重要标志。而综合交通运输体系发展是当代交通运输发展的新趋势、新方向。为健全和完善综合交通运输体系,提出构建综合交通运输服务指数方法,并以陕西省为例,选取铁路、公路、水运、航空、邮政五大运输领域运量数据,通过对缺失值补充、季节调整、无量纲化、熵权法确定权重,进而使用Fisher-ideal方法构建陕西省综合交通运输服务指数,并结合HP滤波处理的周期性分析、重大事件影响分析验证其合理性。结果表明:构建的综合交通运输服务指数能在一定程度上发挥宏观经济的先行指标功能,可展现不同阶段重大事件对交通运输业的影响,具有适用性。

Transport in the Aftermath of COVID-19: Lessons Learned and Future Directions

This paper is a review of the impact on transport in the Asian region where enforced lockdowns and transport reductions have come with real human costs in the areas of economic development and access to jobs, society and services from various perspectives including urban planning and transport, economy, GHG and air pollutant emissions and gender as some of the areas of focus in the Sustainable Development Goals. Transportation systems with a high level of planning, flexible modes of transport and good communication with the public have proved more resilient than others. Furthermore, digital infrastructure has proven to be a key transport solution through this crisis. Data collection and real-time analysis have proven that their time has come to be effective in urban planning and transport management. Digital infrastructure is also driving online shopping and urban delivery services that allow people seeking to be socially distant to access daily necessities in a fast and relatively inexpensive manner. Making use of new global data sets and computing techniques can help cities and countries to plan better. Developing countries will need to improve their ability to gather relevant data from public and private sources and furthermore use the data to achieve more resilient, sustainable transportation. Achieving Sustainable Development Goals will require a reprioritization of funding and efforts to ensure that countries are building optimized infrastructure that provide transport and mobility services with minimal financial burdens including new leapfrog transit systems.

Assessment of the Environmental Impact of Road Infrastructure in Countries: A Study of the Namibia Scenario

The assessment of the impact of road infrastructure in the developing countries using the Namibian case scenario was done based on the contemporary challenges of road use. This study employed a qualitative technique using a sample size of thirty (30) selected by the simple random sampling technique. The use of charts, tables and frequencies were done to explain certain trends in the study. A well-structured, valid and reliable questionnaire instrument was designed for the study based on the following research questions;what are the impacts of road transport on the Namibian environment and what are the possible measures that may be used to reduce environmental impact of road transport on the Namibian environment? Twenty five respondents (83%) agreed that road transfer has drastically improved development and 26 (87%) respondents also accepted that it can improve Namibian economy. Similarly, it has also improved communication and technology greatly according to 27 (90%) respondents. To add more credence to the impact of road transport on the economy, all the 30 (100%) of the respondents agreed that road transport aids mobility within Namibia while 27 (90%) respondents supported the opinion that road transport aids in job search, 3 (10%) disagreed. The result shows that car owners service are potential threats which can affect pollution levels as was supported by 97% to cause environmental pollution as well as 100% when combined with energy consumption. Similarly, all the respondents indicated the potential of increased accident rate from poor road safety. Felling of trees poses great danger (97% response) due to the degradation of the environment. Most respondents (77% and 83%) agreed that road transport can lead to land encroachment and loss of aesthetic and farming. This research has shown that eventually death rate may increase from mere ill-health to from the degraded ecosystem, 24 respondents (80%). So many policies to protect the environment but the practical measures are to encourage impact assessment studies for road projects, land use control and human safety precautions on road use.

Assessment of Beef Transportation Infrastructure from Slaughtering Facilities in Tanzanian Cities

This study presents the assessment of beef transportation infrastructure from slaughtering facilities in Tanzanian cities to the retail premises. The quality of beef consumed in many countries is questionable due to poor infrastructural development which may results into contamination and bacteriological infection. This study was carried out in Mbeya and Dar es Salaam where data was collected at the dispatch areas of 3 and 6 slaughtering facilities, respectively. At each slaughter facility, 10 vehicles selected randomly, were assessed. The assessment of beef distribution infrastructure was conducted based on 18 quality impacting factors established from the actual observation and literature review and conceptualized carcass distribution model. With exception to water tightness, painting and engine status during carcass loading, all the assessed beef quality impacting parameters were below 50%, indicating that beef distribution in the surveyed facilities were below the specification of food quality. Generally, the assessment of beef transporting facilities in connection to the first hypothesis of this study, indicted very weak compliance with the requirements, signifying that the vehicles are not acceptable for carcass transportation.

Unleashing the Potential of Unidirectional Mechanical Materials: Breakthroughs and Promising Applications

The emergence of mechanically one-way materials presents an exciting opportunity for materials science and engineering. These substances exhibit unique nonreciprocal mechanical responses, enabling them to selectively channel mechanical energy and facilitate directed sound propagation, controlled mass transport, and concentration of mechanical energy amidst random motion. This article explores the fundamentals of mechanically one-way materials, their potential applications across various industries, and the economic and environmental considerations related to their production and use.

公路运输罐体抗冲击防护的研究进展

鉴于公路运输罐体重大事故频发、罐体抗冲击防护性能亟待改善,研究公路运输安全性防护问题,尤其是罐体抗冲击防护性能具有重要意义。简要介绍了传统运输罐体材料与结构对罐体抗冲击性能的影响;重点阐述运输罐体在防护材料与防护结构两方面的研究热点;介绍了铝镁合金材料、泡沫铝夹芯材料等材料,以及结构配件与罐体厚度、“三明治”夹芯结构等对冲击荷载缓冲耗能的作用;分析了罐体新型防护材料——喷涂聚脲弹性体、罐体抗撞击防护装置对提高罐体的防撞抗冲击性能的影响;探讨了提高公路运输罐体抗冲击性能的有效方法及措施,指出公路运输罐体在抗冲击防护领域的研究方向和发展趋势。

Automated Autonomous Vehicles: Prospects and Impacts on Society

All automobile manufacturing companies, Google and Microsoft have announced recently their production of the Fully Automated Autonomous Vehicles (FAAVs), otherwise known as driverless cars. A few FAAVs would be available in the market as early as in 2018, but mostly in 2020’s. When FAAVs will be available to and become affordable by the average consumers, the implications to the society would be far reaching. The purpose of the paper is to examine the prospect of the popularity of FAAVs and their socio-economic implications to the future society of the World. The paper examines potential impacts on selected sectors of the society including changes in demand for automobiles, its impact on the use of oil, on the environment, and on urban land uses, to list a few.