关于我国多式联运组织协调影响因素问题的探讨

随着我国集装箱多式联运业务的不断发展,其组织协调工作呈现出日益复杂的局面,各企业往往由于缺乏协调性而难以实现效益最大化。本文针对我国多式联运的组织协调工作中存在的问题,从宏观和微观两个方面对其影响因素进行深入分析,以便于实际工作中的全面分析和考察。     

基于标准潜艇模型的潜艇机械噪声影响因素分析

基于Benchmark标准潜艇模型,建立了不同结构形式的Benchmark标准模型的衍生潜艇模型,包括单层壳潜艇模型和双层壳潜艇模型以及无附体结构和有附体结构的潜艇模型。开展理论解析解计算与数值仿真计算比对,得到数值仿真计算的置信度,并开展Benchmark潜艇缩比模型实验室试验,通过试验验证数值仿真计算的可靠性。基于以上研究,针对潜艇机械噪声开展数值计算,计算得到在海洋流场环境中不同结构形式的Benchmark潜艇模型的固有振动特性以及其受到机械设备激励作用下的机械辐射噪声值,并通过对比分析得到了不同激励形式、不同潜艇艇体结构特性对其机械噪声的影响规律。     

铜合金腐蚀的影响因素及研究状况

本文先叙述了铜合金的应用领域,并指出其腐蚀行为研究的必要性。然后分别阐述了不同的影响因素对铜合金的腐蚀行为及研究状况的影响,其影响因素主要就铜合金自身的组织成分、铜合金的热处理及所处环境条件这三方面进行阐述。最后对铜合金的腐蚀规律进行了总结与展望。     

基于影响因素的SVR备件需求预测研究

文章介绍了支持向量机学习算法,说明其特点,并引出基于影响因素的支持向量回归的备件需求预测方法,用某型备件的历史需求数据例证此法的可行性与精确度。     

长江中游新洲汇流口浅滩演变影响因素分析及治理问题初探

分析新洲水道两汊汇流口形态特征及汇流口浅滩年内年际间变化特征,探讨浅滩出浅变化的影响因素。结果认为:新洲南汊汇流顶托对汇流口浅滩的影响是存在的,但不是主要因素,新洲南水道上深槽走向以及北水道入流的变化是汇流口浅滩出浅的主要原因。在此基础上,对汇流口浅滩治理思路进行探讨。     

山东省临港产业集群的影响因素研究

为了使山东省沿海地区未来能够快速健康发展,从而带动山东经济的总体增长,分析、研究山东省临港产业群的影响因素及发展方向非常重要。分别分析了影响山东省临港产业群的促进因素和限制因素,从4个方面提出了大力培育山东临港产业群的措施。     

水利工程施工质量的影响因素及其控制措施研究

为了全面提升水利工程施工水平,要落实全过程质量管理分析机制,打造更加和谐规范的管控平台,减少不确定因素对工程项目产生的影响,实现经济效益和社会效益的和谐统一.本文分析了水利工程施工质量影响因素,并着重讨论了水利工程施工质量控制措施.     

边坡稳定性影响因素数学模型的研究

在分析边坡稳定影响因素的基础上,提出了判别边坡稳定影响因素敏感性的逐步回归的分析方法。以模型计算和逐步回归分析为手段,通过计算机程序和数理统计分析来评价边坡稳定影响因素的敏感性。通过对12例工程边坡主要参数进行逐步回归分析,提出了影响边坡稳定安全系数的影响因素敏感性的大小并讨论了逐步回归分析方法的有效性。     

基于SEM的港口集疏运系统影响因素研究

港口集疏运系统的影响因素是复杂而又相互关联的,分析各因素之间的影响程度有利于辨识系统结构。文章以我国沿海主要港口为样本,通过定性与定量相结合的方法,采用结构方程模型(SEM)对港口集疏运系统影响因素进行分析。通过数据分析及专家打分得出基础数据,利用AMOS软件绘制出其路径模型图,计算出其路径系数,进而分析得出主要的影响因素。     

不同坝型丁坝坝体周围水流紊动特性试验研究*

通过水槽试验,结合理论分析,研究丁坝附近水流紊动强度沿水流方向、水深方向和横向的分布规律。绘制5种不同坝体结构形式其周围水流脉动动能和紊动强度的分布等值线图并分析分布规律,进一步探讨不同坝体挑角对丁坝附近水流紊动强度和脉动动能的影响。     

A study of factors influencing the severity of road crashes involving drunk drivers and non drunk drivers

In this study, an attempt has been made to develop Multinomial Logit (MNL) model by analysing the drunken and non drunken drivers involved in road crashes on Indian highways. Multinomial Logit model has been deployed to assess the influence of various parameters like vehicular, environment and geometric factors on the set of drivers who were found to be drunk at the time of getting involved in the road crash and those who were not under the influence of alcohol at the time of meeting with the road crash. The total economic cost of road crashes in the case of non-drunk driver road crash is Rs. 1046.27 million whereas in the case of drunk driver road crashes it is estimated to be Rs. 204.50 million. Further, it can be observed that economic cost of drunk driver road crashes is varying from 13 to 19 % across different types of road crashes.     

模糊模式识别在导航系统性能综合评价中的应用研究

就导航系统抗干扰性能评价问题指标的多层次性,根据模糊模式识别的原理,对现有的模糊模式识别方法进行改进,提出了一种新方法.该方法首先将系统分为3个等级,并把它们看作3个模糊模式,根据试验所测得的数据构造各模式的隶属函数,然后采用反向递推的方法从指标体系的最底层出发依次计算待评系统与各模式的加权贴近度,最后由模糊模式识别的择近原则得出待评系统所属的等级.最后应用此方法对某一导航系统进行评价,给出此系统所属的等级.     

CFD-based method of determining form factor <Emphasis Type="Italic">k</Emphasis> for different ship types and different drafts

The value of form factor k at different drafts is important in predicting full-scale total resistance and speed for different types of ships. In the ITTC community, most organizations predict form factor k using a low-speed model test. However, this method is problematic for ships with bulbous bows and transom. In this article, a Computational Fluid Dynamics (CFD)-based method is introduced to obtain k for different type of ships at different drafts, and a comparison is made between the CFD method and the model test. The results show that the CFD method produces reasonable k values. A grid generating method and turbulence model are briefly discussed in the context of obtaining a consistent k using CFD.     

多因素下滨海软黏土循环后强度弱化研究及应用

随着近海工程向深水化、大型化发展,波浪循环荷载作用下软黏土地基弱化问题越来越受到关注。文章以烟台港原状淤泥质黏土为研究对象,通过动三轴试验,研究了不同围压、动应力和静偏应力影响下循环后不排水抗剪强度弱化规律和应力路径发展规律。在此基础上考虑实际工程中的土体状况,增加了固结度这一新的影响因素。试验结果表明存在固结度临界动应力比0.2,当动应力比小于等于0.2时,固结度对于土体强度弱化的影响基本一致;当动应力比大于0.2时,固结度对于强度弱化的影响突然加速。根据试验规律建立了综合考虑围压、动应力、静偏应力和固结度的多因素影响下不排水抗剪强度弱化公式,并采用拟静力方法将公式应用于烟台港防波堤数值模型的计算中,结果表明考虑强度弱化效应的计算方法更加接近工程实际。     

KG<Subscript>max</Subscript> curves associated with second generation intact stability criteria for different types of ships

Currently, second generation intact stability criteria are being developed and evaluated by the International Maritime Organization (IMO). In this paper, we briefly present levels 1 and 2 assessment methods for the criteria of pure loss of stability and parametric roll failure modes. Subsequently, we show the KG_max curves associated with these criteria. We compute these curves for five different types of ships and compare them with the curves embodied in the current regulations. The results show that the safety margin ensured by the first level-1 method of calculation for both pure loss of stability and parametric roll seems to be excessive in many cases. They also show that the KG_max given by the second level-1 method and by the level-2 method may be very similar. In some cases, the level-2 method can be more conservative than the second level-1 method, which is unanticipated by the future regulation. The KG_max curves associated with parametric roll confirm that the C11 container ship is vulnerable to this failure mode. The computation of the second check coefficient of parametric roll level 2 (C2) for all possible values of KG reveals the existence of both authorized and restricted areas on the surface formed by both the draft and KG, which may replace the classical KG_max curves. In consequence, it is not sufficient to check that C2 is lower than the maximum authorized value (R _PR0) for a fixed ship’s loading condition.     

Risk perception in the Norwegian shipping industry and identification of influencing factors

In the recent years, safety culture in relation to shipboard safety and organizational factors has received increasing interest within the shipping industry. This study examines this relationship, where risk perception is an indicator for shipboard safety. Data was derived from a survey carried out in 2006, where 1262 questionnaires were collected from 76 vessels. Explorative factor analyses were used to extract factors of safety culture. Analysis of variance was used to assess the associations between the safety cultural factors and demographic and organizational variables. Finally, linear regression analysis was carried out to assess the association between risk perception and safety culture, controlling for the influence of demographic and organizational variables; age, department, vessel type and nature of work. The results suggest that safety-oriented shipboard management style, performance of proactive working practices and good reporting practices all contribute to a better perception of shipboard safety, while a high demand for efficiency contributes to a more negative perception of the safety level. Further, safety is perceived as better when work is performed as a team. To gain a better understanding of risk perception and safety at sea, it would be helpful to further examine the characteristics and influences of teamwork.     

影响篮球技术预判的因素及练习方法

通过文献资料法以及在实践中的运用,探讨了篮球技术预判在比赛中的作用、意义以及影响篮球技术预判的若干因素,为改善、提高对篮球技术动作的预见能力,列举一些在实战中常用的加强对技术动作预见性训练的若干内容和方法。     

浮式LPG回收系统工艺模块总体布置影响因素分析

作为国内设计、建造、安装的浮式LPG回收系统,设计初期的总体布置尤为关键,直接决定了后期结构设计的难度.文章基于此浮式LPG回收系统工艺模块,分析讨论模块结构总体布置的影响因素,旨在项目初期,尽可能将浮式LPG回收系统工艺模块的整体布置考虑全面,结构模块设计与工艺管线、工艺设备互相制约,设计中必须协调考虑,避免后期疲劳...     

海事主管机关进行集装箱载运货物开箱检查的几个问题思考

论述了集装箱载运危险货物瞒报现象的实际情况,指出对集装箱内货物进行开箱抽查的必要性,重点论述了海事主管机关对集装箱危险货物瞒报行为检查的合法性和合理性,提出海事主管机关应当积极主动对集装箱货物进行开箱抽查,严厉打击利用集装箱进行危险货物瞒报行为,履行海上运输安全监管的法定职责。