中东现汇EPC项目全周期的设计管控

中东现汇EPC项目具有设计采购施工一体化程度高、合同理念强、设计变更多和设计报批流程复杂等特点,这对于走出去的设计企业来说具有很大的挑战性,也是能力提升和快速国际化的良好机会。阐述EPC项目的核心理念,提出设计应在EPC项目中发挥龙头作用和创造价值,从EPC全生命周期的前期准备、项目投标、项目策划、项目设计、设计报批和施工配合六大方面详细论述设计的核心内容和管控重点,并通过中东典型工程案例加以说明,希望能为国际EPC项目设计方面的更好实施提供借鉴和参考。     

护坡垫层渗透系数对面层波浪上举力的影响

在工程应用中,对于波浪作用下的护岸工程,护坡通常采用面层-垫层-堤心土的设计模式,其垫层一般采用反滤层结构。但在实际工程中垫层结构往往被简化,直接将土工布铺设在砂层上。通过理论分析和模型试验,主要针对这种垫层结构在波浪作用下所受的影响进行了研究,得出了结论：当面层渗透系数小于垫层渗透系数时,在垫层内部会产生对面层的上举力,从而可能引起面层失稳。该成果对类似工程有一定的借鉴作用。     

EPC项目专业设计计划管理技术与方法研究

本文针对大多数从事海洋工程项目设计计划管理过程中经常遇到的一些问题,结合海洋石油工程股份有限公司近年来在设计信息化管理方面的一些实践经验,以及借鉴行业一些先进经验,引入项目总控计划和设计执行计划分级管理方法,基于专业设计成果清单,以专业设计计划为核心,结合IT技术,对项目设计计划管理和任务管理方法进行优化设计,并用于指导《自升式钻井平台设计建造信息化管理技术研究》项目中设计管理模块的管理模式设计和信息系统开发工作,管理模式的设计思路和信息系统实现效果,获得相关方肯定。     

美国舰船及编队通信手段分析

通信是舰艇编队实施作战指挥控制的重要基础,在舰艇编队作战指挥中发挥着至关重要的作用。本文梳理了美国海军舰艇编队基本的无线通信手段及其管理方式,并归纳了其特点。     

中美日海洋执法机构的组织架构对比

海上执法机构是海洋执法和管理的核心力量,目前我国海上执法机构正处于体制建设的初期阶段,逐步由分散型海洋管理模式向综合型模式转变.为促进我国海上执法机构的体制完善,提升我国海上执法效能,本文整理和对比分析了中国、美国及日本海上执法机构的组织结构.同时,结合美日海洋执法机构相对成熟组织架构,从执法依据及教育培养两方面,提出了我国海上执法机构的发展建议.     

A methodology for identifying similar days in air traffic flow management initiative planning

This article describes a methodology for selecting days that are comparable in terms of the conditions faced during air traffic flow management initiative planning. This methodology includes the use of specific data sources, specific features of calendar days defined using these data sources, and the application of a specific form of classification and then cluster analysis. The application of this methodology will produce results that enable historical analysis of the use of initiatives and evaluation of the relative success of different courses of action. Several challenges are overcome here including the need to identify the appropriate machine learning algorithms to apply, to quantify the differences between calendar days, to select features describing days, to obtain appropriate raw data, and to evaluate results in a meaningful way. These challenges are overcome via a review of relevant literature, the identification and trial of several useful models and data sets, and careful application of methods. For example, the cluster analysis that ultimately selects sets of similar days uses a distance metric based on variable importance measures from a separate classification model of observed initiatives. The methodology defined here is applied to the New York area, although it could be applied by other researchers to other areas.     

Motorway crash duration and its determinants: do durations vary across motorways?

Traffic congestion has been a growing issue in many metropolitan areas during recent years, which necessitates the identification of its key contributors and development of sustainable strategies to help decrease its adverse impacts on traffic networks. Road incidents generally and crashes specifically have been acknowledged as the cause of a large proportion of travel delays in urban areas and account for 25% to 60% of traffic congestion on motorways. Identifying the critical determinants of travel delays has been of significant importance to the incident management systems, which constantly collect and store the incident duration data. This study investigates the individual and simultaneous differential effects of the relevant determinants on motorway crash duration probabilities. In particular, it applies parametric Accelerated Failure Time (AFT) hazard‐based models to develop in‐depth insights into how the crash‐specific characteristic and the associated temporal and infrastructural determinants impact the duration. AFT models with both fixed and random parameters have been calibrated on one year of traffic crash records from two major Australian motorways in South East Queensland, and the differential effects of determinants on crash survival functions have been studied on these two motorways individually. A comprehensive spectrum of commonly used parametric fixed parameter AFT models, including generalized gamma and generalized F families, has been compared with random parameter AFT structures in terms of goodness of fit to the duration data, and as a result, the random parameter Weibull AFT model has been selected as the most appropriate model. Significant determinants of motorway crash duration included traffic diversion requirement, crash injury type, number and type of vehicles involved in a crash, day of week and time of day, towing support requirement and damage to the infrastructure. A major finding of this research is that the motorways under study are significantly different in terms of crash durations; such that motorway 1 exhibits durations that are on average 19% shorter compared with the durations on motorway 2. The differential effects of explanatory variables on crash durations are also different on the two motorways. The detailed presented analysis confirms that looking at the motorway network as a whole, neglecting the individual differences between roads, can lead to erroneous interpretations of duration and inefficient strategies for mitigating travel delays along a particular motorway.     

长春地铁解放大路站基于三维数值模拟的地铁车站施工工法优化分析

为了对地铁车站施工工法进行优化分析,依托长春地铁解放大路站工程,采用数值模拟方法建立数值模型,从中轴线上方地表沉降、拱顶沉降和拱顶应力3方面对6导洞PBA工法、8导洞PBA工法以及一次扣拱暗挖逆作法进行了对比分析,得到： 1）在施工过程中,3种工法的中轴线上方地表沉降、拱顶沉降和拱顶应力变化规律存在明显差异; 2）通过综合对比分析,一次扣拱暗挖逆作法最优,6导洞PBA工法最差。得到的对比分析结果对现场施工具有指导意义。     

农村公路养护与管理的现状分析及对策研究

针对内蒙古自治区农村公路发展现状,分析了目前农村牧区公路在养护与管理方面存在的问题,并对如何完善农村牧区公路管理与养护机制提出了建设性的意见。     

论我国公路交通应急及运输保障体系的建设

针对自然灾害或重大事件(如5.12四川汶川发生的8级地震;2007年末,2008年初之际,我国南方大部分地区发生50年一遇的特大雪灾等)引发的应急情况的运输物资保障问题,一些机场关闭,公路、铁路部分路段封闭,给人民群众出行和物资运输带来极大困难,交通应急运输需求显得更加迫切。以国外公路应急及运输保障的经验以及对我国建立应急运输保障体系的启迪为依据,运用系统方法论,通过比较法,分析研究了我国公路交通应急运输保障的发展状况并深入剖析了我国在公路交通应急运输方面存在的主要问题,提出了构建我国应急物资运输保障体系的措施与建议。