重交通路段未设仰拱隧道富水段路面病害处治

针对重交通路段未设仰拱隧道富水段路面病害较多的问题,以大普吉隧道为分析对象,介绍了隧道病害情况,在此基础上分析了未设仰拱隧道富水段路面病害原因,并提出了相应的处治措施。

南京市轨道交通管理条例

南京市人民代表大会常务委员会公告(第6号)《南京市轨道交通管理条例》已由南京市第十四届人民代表大会常务委员会第四次会议于2008年7月31日制定,江苏省第十一届人民代表大会常务委员会第五次会议于2008年9月28日批准,现予公布,自2009年1月1日起施行。

北京市户外广告设置管理办法

北京市人民政府令第151号《北京市户外广告设置管理办法》已经2004年6月22日市人民政府第27次常务会议通过,现予公布,自2004年10月1日起施行。

Spatial spillover effects of transport infrastructure on regional economic growth

Spatial spillover effects,either positive or negative,of transport infrastructure,highways/expressways,etc.,on regional economic growth are proposed.Using the panel data for 11 cities of Zhejiang province from 1994 to 2003,a spatial production function is applied to examine the spatial spillovers which can be generated as a positive output spillover from the transport infrastructure between neighboring cities.Some spatial weighted matrices are adopted to define different neighboring cities to measure how easily factors or economic activities can migrate between regions.The estimation results show that the output elasticity of the highway infrastructure in 11 cities are all insignificant at a 5% significance level;hence,highway infrastructure in a region cannot explain the same region's economic growth.On the other hand,the highway infrastructure of other contiguous regions has positive spillover effects on a same region's economic growth.

Private Car Travel Characteristics and Influencing Factors in Chinese Cities——A Case Study of Guangzhou in Guangdong,China

Taking Guangzhou as a case,this paper adopted a questionnaire survey to gather first-hand data and analyzed the characteristics and influencing factors of private car travel in Chinese cities.As the research indicated,trip purposes of private car travel are mainly commute and business affairs with a more flexible trip in the urban core area.And trip intensities are concentrated in a certain extent,with trip frequency being lower in the urban core area than the peripheral area.In addition,the trip time has two significant peaks occurring in the morning and afternoon,and one trough in the midday.And trip spatial distribution is mainly within commute with both residence and employment in urban area and inward commute with residence in suburban area while employment in urban area.Both kinds of commutes direct to the urban area.The study also shows that the characteristics of private car travel are principally influenced by two aspects:travelers' attributes and urban characteristics.The main travelers' social and economic attributes influenced it include the gender,education attainment,age,driving experience and per capita monthly household income.The urban characteristics influenced it mainly cover the land use pattern,public traffic facilities and spatial attributes of residential environment.

Effects of Boundary Conditions on the Design of Anti-Ram Bollards

Anti-ram bollards used in perimeter protection are tested to meet performance requirements of established standards such as the US Department of State Specification SD-STD-02.01. Under these standards, tests are conducted in prescribed conditions that should be representative of the service installation. In actual project, conditions encountered on site may vary from the test environment and it would be expensive and time consuming to validate each deviation with a physical test. High-fidelity physics-based (HFPB) finite element modeling can provide precise simulations of the behavior of anti-ram bollards. This paper presents the use of HFPB finite element modeling, using LS-DYNA, in an actual project to evaluate the performance of an anti-ram bollard design subjected to various boundary conditions representing the physical conditions encountered on site. The study shows that boundary conditions can have a significant influence on the performance of the anti-ram bollards. This suggests that anti-ram bollards must be designed and engineered according to actual conditions that are found on site. It also shows that HFPB modeling can be an effective tool that supplements physical testing of anti-ram bollards.

RELATION BETWEEN THE MRT BUILDING AND UNDERGROUND SPACE EXPLOITATION——A Case in Guangzhou City

On the basis of analyzing the history and characteristics of the undergroundspace exploitation and the urban space development in Guangzhou, and making a thorough study on theunderground space exploitation based on the subway building, this paper points out some mam problemsin the exploitation of underground space in Guangzhou, and emphasizes that Guangzhou must developthe underground space on a large scale with the aid of the subway building, and puts forward aproposal on the urban space coordinate development between on-ground and underground in GuangzhouCity.

Design and evaluation of a hierarchical control architecture for an autonomous underwater vehicle

This paper researches on a kind of control architecture for autonomous undelwater vehicle （AUV）. After describing the hybrid property of the AUV control system, we present the hierarchical AUV control architecture. The architecture is organized in three layers： mission layer, task layer and execution layer. State supervisor and task coordinator are two key modules handling discrete events, so we describe these two modules in detail. Finally, we carried out a series of tests to verify this architecture The test results show that the AUV can perform autonomous missions effectively and safely. We can conclude the control architecture is valid and practical.

Empirical Analysis of City Contact in Zhujiang(Pearl) River Delta, China

In traditional urban geography, city contact research is a classic study element in city research. In general, researchers use the traditional gravity model to characterize the contacts that exist between two cities. The traditional gravity model assumes ideal conditions, but these preconditions and their results often do not exist in realistic conditions. Thus, we used a modified gravity model to characterize the city contacts within a specific region. This model considers factors such as intercity complementarities, government intervention, and the diversity of the transportation infrastructure which is characterized as the transportation distance instead of the traditional Euclidean distance. We applied this model to an empirical study of city contact in the Zhujiang(Pearl) River Delta(PRD) of China. The regression results indicated that the modified gravity model could measure city contact more accurately and comprehensively than the traditional gravity model, i.e., it yielded a higher adjusted R2 value(0.379) than the traditional gravity model result(0.259). Our study also suggests that, in addition to urban-regional and metropolitan development, the complementarities of the basic functions of cities at the administrative and market levels, as well as the corporeal and immaterial levels, play very significant roles in the characterization of city contact. Given the complexity of city contact, it will be necessary to consider more relevant influential factors in the modified gravity model to characterize the features of city contact in the future.

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.

Applications of Pre-Geological Prediction in Tunnel Construction

Pre-geological prediction (PGP) is defined as the prediction of engineering geologic condition and hy-drogeological condition certain distance ahead of the working face. The purpose of this paper is to introduce mainlygeologic survey before and in excavation, to clarify their emphasis on PGP. At the same time, the technique is appliedto an engineering case, the longest highway tunnel in Gansu province. Data of geological survey of outside tunnels,sound wave detection, and geologic sketch for both tunnel face and sidewalls within the tunnel are analyzed. Afteranalyzing these data, long-term pre-geological prediction forecasting basic geological conditions of fault 4 such aslithology, scope, location, etc., and short-term and more accurate pre-geological prediction are reported.

Deep-seated large-scale toppling failure in metamorphic rocks：a case study of the Erguxi slope in southwest China

Deep-seated large-scale toppling failure presents unique challenges in the study of natural slope deformation process in mountainous regions.An active deep-seated toppling process was identified in the Erguxi slope located in southwest China,which affected a large area and damaged critical transportation infrastructure with the volume of the deforming rock mass exceeding 24×10~6 m^3.It poses significant risks to the downstream Shiziping Hydropower Station by damming the Zagunao River.Field investigation and monitoring results indicate that the deformation of the Erguxi slope is in the advanced stage of deep-seated toppling process,with the formation of a disturbed belt but no identifiable master failure surface.It was postulated that the alternating tensile and shear strength associated with the hard/soft laminated rock strata of metasandstone and phyllite layers preclude the development of either a tensile or shear failure surface,which resulted in the continuous deformation and displacement without a catastrophic mass movement.The slope movement is in close association with the unfavorable geological conditions of the study area in addition to the construction of transportation infrastructure and the increase of the reservoir level.On the basis of the mechanism and intensity of the ongoing toppling deformation,a qualitative grading system was proposed to describe the toppling process and toevaluate the slope stability.This paper summarized the field observation and monitoring data on the toppling deformation for better characterizing its effect on the stability of the Erguxi slope.The qualitative grading system intends to provide a basis for quantitative study of large-scale deep-seated toppling process in metamorphic rocks.

Numerical model of soft ground improvement by vertical drain combined with vacuum preloading

The rapid development of high-speed transportation infrastructure such as highway and high-speed railway has resulted in the advancement of soft soil improvement techniques. Vacuum preloading combined with vertical drains has been proved to be an effective method in the treatment of soft foundation. A three-dimensional numerical analysis of the coupled methods was presented, in which the smear zone and the well resistance were taken into account. The variations of the basic soil parameters including the permeability coefficient and the coefficient of volume compressibility were considered in the numerical model. The result of the numerical model was then compared to the measured value. The results indicate that the decrease of coefficient of volume compressibility accelerates the consolidation of the soil while the influence of hydraulic conductivity is insignificant. A cube drain presents the closest result to the real situation compared to the other equivalent methods of prefabricated vertical drain (PVD). The case study indicates that the numerical model with variation of soil parameters is closer to the measured value than the numerical model without variation of soil parameters.

The spatial distribution of commuting CO_2 emissions and the influential factors:A case study in Xi'an,China

As the transport sector is a major source of greenhouse gas emissions, the effect of urbanization on transport CO2 emissions in developing cities has become a key issue under global climate change. Examining the case of Xi＇an, this paper aims to explore the spatial distribution of commuting CO2 emissions and influencing factors in the new, urban industry zones and city centers considering Xi＇an＇s transition from a monocentric to a polycentric city in the process of urbanization. Based on household survey data from 1501 respondents, there are obvious differences in commuting CO2 emissions between new industry zones and city centers： City centers feature lower household emissions of 2.86 kg CO2 per week, whereas new industry zones generally have higher household emissions of 3.20 kg CO2 per week. Contrary to previous research results, not all new industry zones have high levels of CO2 emissions; with the rapid development of various types of industries, even a minimum level of household emissions of 2.53 kg CO2 per week is possible. The uneven distribution of commuting CO2 emissions is not uniformly affected by spatial parameters such as job-housing balance, residential density, employment density, and land use diversity. Optimum combination of the spatial parameters and travel pattern along with corresponding transport infrastructure construction may be an appropriate path to reduction and control of emissions from commuting.

The Impact of the Maputo Development Corridor on Wealth Creation within the Region It Serves

The Maputo Development Corridor along the N4 toll road between the north-eastern provinces of South Africa and Maputo （the capital and main port of Mozambique） was initiated in 1996. A Development Corridor can be seen as a concept to elevate an area to a certain level of development. One of the objectives of this project was investment in transport infrastructure in order to create an enabling environment for economic growth and development. The project is also in line with the 1995 Spatial Development Initiatives of the South African Government that attempt to improve investment in those areas were the greatest potential for growth exists. This paper addresses economic wealth creation within the broader region that the N4 toll road and the corridor currently serve. The research revealed that the areas closer to the N4 corridor had higher growth in terms of economic output as measured by Gross Valued Added than those further removed. There were a stronger correlation between growth in employment and proximity to the road corridor for the manufacturing, construction, trade and transport sectors. Analysis done also shows that income per capita has grown at a faster rate in areas closer to the corridor that areas further removed.

Intelligent Resources Management System Design in Information Centric Networking

Information centric networking(ICN) is a new network architecture that is centred on accessing content. It aims to solve some of the problems associated with IP networks, increasing content distribution capability and improving users' experience. To analyse the requests' patterns and fully utilize the universal cached contents, a novel intelligent resources management system is proposed, which enables effi cient cache resource allocation in real time, based on changing user demand patterns. The system is composed of two parts. The fi rst part is a fi ne-grain traffi c estimation algorithm called Temporal Poisson traffi c prediction(TP2) that aims at analysing the traffi c pattern(or aggregated user requests' demands) for different contents. The second part is a collaborative cache placement algorithm that is based on traffic estimated by TP2. The experimental results show that TP2 has better performance than other comparable traffi c prediction algorithms and the proposed intelligent system can increase the utilization of cache resources and improve the network capacity.

PM10 and CO Exposure of Hong Kong Population in Public Transit Facilities

Taking public transit facilities (PTFs) is the major transport style in Hong Kong. Human exposure to indoor air pollutants may cause adverse health effects to the passengers. Exposure assessment on air pollutants is important for the control of human diseases caused by indoor air pollution. In this paper, the indoor PM10, CO and CO 2 levels in various PTFs, such as public bus, subway, railway and ferry in Hong Kong, were mea- sured. Combining with the time budget survey of Hong Kong population,the human exposures were calculated through Monte-Carlo simulation.

The Innovation and Development of Internet of Vehicles

With the advancements in wireless sensor networks, Internet of Vehicles(IOV) has shown great potential in aiding to ease traffic congestion. In IOV, vehicles can easily exchange information with other vehicles and infrastructures, thus, the development of IOV will greatly improve vehicles safety, promote green information consumption and have a profound impact on many industries. The purpose of this paper is to promote the innovation and development of IOV. Firstly, this paper presents general requirements of IOV such as guidelines, basic principles, and the goal of development. Secondly, we analyze critical applications, crucial support, and business model to promote the industrial development of IOV. Finally, this paper proposes some safeguard measures to further promote the development of IOV.

Simultaneous optimization of transit network and public bicycle station network

The traditional manner to design public transportation system is to sequentially design the transit network and public bicycle network. A new public transportation system design problem that simultaneously considers both bus network design and public bicycle network design is proposed. The chemical reaction optimization(CRO) is designed to solve the problem. A shortcoming of CRO is that, when the two-molecule collisions take place, the molecules are randomly picked from the container.Hence, we improve CRO by employing different mating strategies. The computational results confirm the benefits of the mating strategies. Numerical experiments are conducted on the Sioux-Falls network. A comparison with the traditional sequential modeling framework indicates that the proposed approach has a better performance and is more robust. The practical applicability of the approach is proved by employing a real size network.

Design of Bridge Expansion Joints with Perforated Dowels Under Impact Loading

The expansion joints are expected to have movement capacity, bearing capacity for static and dynamic loading, water-tightness, low noise emission and traffic safety. In particular, the failure due to impact loading is the main reason for the observed damages. The problem of dynamic behavior of the expansion joints is so complex that we shall focus our attention on the impact factor for vehicle load that is governed by traffic impact. In order to overcome this difficulty, the cantilever-toothed aluminum joint (finger joint) is one of the promising joints under impact loading. In this study, from the viewpoint of design methodology, numerical studies for impact behavior were conducted for aluminum alloy expansion joints with perforated dowels. The design impact factor for the expansion joints with the perforated dowels against traffic impact loading was examined by using numerical simulations.