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1.
This article is based on 183 819 port state control inspections from various port state control regimes for the time frame 1999 to 2004. Using binary logistic regression, we establish the differences of port state control inspections across several regimes, even though theory predicts there should be no significant differences in treatments of vessels. The results indicate that the differences towards the probability of detention are merely reflected by the differences in port states and the treatment of deficiencies and not necessarily by age, size, flag, class or owner as perceived by the industry and regulators. The analysis further shows that some differences can be found across ship types and regimes and that there appears to be room for further harmonization in the area of port state control.  相似文献   

2.
The factors to consider in selecting which vessels to board for port state control (PSC) inspections are crucial. This paper tries to identify these factors using 4080 reported PSC inspections from the Swedish Maritime Administration for the period 1996-2001. It relies on count data models and compares results from the Poisson, negative binomial, random effect and random parameters models. The results suggest that three factors are the main determinants of the number of reported deficiencies: the age at inspection, the flag of registry and the type of ships. Conversely, the year when the inspection occurs does not seem to be a significant factor. Estimations also stress that the relationship between the age at inspection and the number of deficiencies detected is not similar for different vessel types. For instance, the number of deficiencies detected decreases for chemical carriers and Ro-Ro passenger vessels older than 25 and 22 years old, while for instance the effect is rather small for tanker and bulk carriers and only occurs when vessels are older than 35 years.  相似文献   

3.
ABSTRACT

The inspection of foreign ships in national ports is a critical measure in port state control (PSC), preventing substandard ships from entering national ports. Multifarious inspection items, limited inspection time and inspector manpower are challenging PSC inspection. This research applies data mining to analyze historical PSC inspection records in Taiwan’s major ports to extract potential valuable information for PSC onboard inspections. Using the Apriori Algorithm, the analysis identifies many useful association rules among PSC deficiencies in terms of specific ship characteristics, such as ship types, societies, and flags. The general rules identified show that the items ‘Water/Weathertight conditions’ and ‘Fire safety’ are significantly related. Besides, in the analysis of the various ship types, several different rules are found. After comparing the analysis of ship types and ship societies, it can be observed that the association rules for specific ship types, such as oil tankers, have a better effect than those for individual ship societies do. These identified rules can not only help inspectors effectively spot the associated deficiencies, but also improve the efficiency of PSC inspection. The ports other than Taiwan’s ports can apply a similar analysis method to identify corresponding association rules suitable for their own inspections.  相似文献   

4.
This study compares the evolution of container port systems in China and the USA in terms of port throughput, number of container ports and the concentration level in the container port system, based on the time-series data on these three features over the period 1979–2009 for China and 1970–2009 for the USA. The results show that the densities of container ports in the two countries are similar, and their evolutionary processes are alike, which has led to a comparable market structure in the port industries of the two countries. In addition, the disparities between container ports closely represent the unevenness in the regional economic development. We further compare the port management regimes of the two countries in terms of the administrative processes for port development and expansion, the ownership structure and the providers of port functions, which offer some explanation on the dynamics of port evolution in the two countries. In conclusion, it can be seen that the evolution of the container port system and the management regime in the USA can be a de facto reference for the future development of the Chinese container port system.  相似文献   

5.
通过对配置HRBF500高强钢筋的混凝土梁在集中荷载作用下的受剪试验,并依据《水运工程混凝土结构设计规范》条文规定,研究该高强钢筋在港口工程混凝土受剪构件中的应用。试验观测构件斜裂缝开展规律及破坏形态,采集构件不同状态时的荷载数据。依据《港口工程荷载规范》条文规定,并引入荷载长期影响系数,分析构件斜截面极限承载力及正常使用极限状态斜裂缝宽度。研究结果表明,配置高强钢筋的混凝土梁斜向开裂规律与普通梁基本相同,其钢筋强度可以被充分利用,基于水运规范所得极限承载力和考虑荷载长期影响的正常使用阶段斜裂缝宽度满足要求,且有较好的安全储备。  相似文献   

6.
The fast growth of the Chinese economy and its international seaborne trade has escalated the demand for high-quality and efficient port services. “Decentralization” of the port management regime has given local government greater freedom in port development and operational decision-making. However, major port capacity expansion in coastal areas, coupled with the slowing down of both the economy and trade growth over recent years, has led to overcapacity and excessive competition. Although both port specialization and government regulations are called for to address these issues, few studies have investigated the formation mechanism and economic implications of port specialization. This paper uses alternative duopoly games, namely a Stackelberg game and a simultaneous game, to model port competition, where ports provide differentiated services in the sectors of containerized cargo and dry-bulk cargo. Our analytical results reveal that inter-port competition can lead to port specialization in the following three ways. A port can specialize in a type of cargo (1) for which there is relatively high demand, (2) where it has established capacity first, or (3) for services which require prohibitively high capacity costs. Also, it is seen that overcapacity is likely if strategic port decisions are made simultaneously instead of sequentially. These results suggest that if there is a clear market leader, policy intervention may not be necessary. However, if no port has clear market power, then government coordination and intervention may be needed in order to prevent overcapacity and to encourage specialization.  相似文献   

7.
基于港口建设导致近岸沿线海、陆域生态系统环境逐渐退化的现状,以集装箱港区为例,进行港区陆域低影响开发研究。将海绵城市低影响开发概念融入港区建设,通过引入合理水文径流分析模型,对港区各功能区的低影响开发提出径流控制要求;同时,采用创新性的平面及结构设计方案满足低影响开发控制要求,促进集装箱港区雨洪资源的重复利用。结果表明,在各类码头中,较为适合进行低影响开发的主要为件杂货及集装箱堆场;海绵港区须重点针对堆场及道路进行低影响开发。  相似文献   

8.
中化泉州码头采用直径为2.2 m和2.6 m的灌注桩作为基桩,由于大直径灌注桩在水运工程中比较少见,其清渣、混凝土浇筑等施工中的质量控制比较复杂,在施工前期产生了桩底盆形沉渣和桩间夹渣的异常情况。通过现场分析,清孔后泥浆中含砂率的大小直接影响着沉渣厚度。总结水运工程中常规灌注桩施工质量控制技术,提出更严格标准以满足大直径灌注桩施工质量要求。在施工中采用气举反循环并结合泥浆净化装置进行清渣,与传统正循环清孔相比,其质量和效率得到了显著改善。该套设备可使泥浆中的含砂率由常规要求的4%~6%有效降低至2%以下有效,灌注桩桩身完整性得到了进一步保证,施工质量很好地满足了规范要求。  相似文献   

9.
This paper investigates whether deficiencies detected during port state control (PSC) inspections have predictive power for future accident risk, in addition to other vessel-specific risk factors like ship type, age, size, flag, and owner. The empirical analysis links accidents to past inspection outcomes and is based on data from all around the globe of PSC regimes using harmonized deficiency codes. These codes are aggregated into eight groups related to human factor aspects like crew qualifications, working and living conditions, and fatigue and safety management. This information is integrated by principal components into a single overall deficiency index, which is related to future accident risk by means of logit models. The factor by which accident risk increases for vessels with above average compared to below average deficiency scores is about 6 for total loss, 2 for very serious, 1.5 for serious, and 1.3 for less-serious accidents. Relations between deficiency scores and accident risk are presented in graphical format. The results may be of interest to PSC authorities for targeting inspection areas, to maritime administrations for improving asset allocation based on prediction scenarios connected with vessel traffic data, and to maritime insurers for refining their premium strategies.  相似文献   

10.
This work analyses whether port state control (PSC) has been effective in reducing environmental pollution in the region it covers. The analysis covers the technical and political aspects of PSC's effectiveness. To match the complexity of marine environmental pollution and safety issues, several indicators are developed to assess performance under both aspects. Previous studies on quantitative and qualitative material, as well as fresh evidence, are utilized to obtain quantitative or qualitative evaluations, as the case may be. The separate insights are then combined to reach an integrated conclusion. PSC is found to be effective in fighting marine environmental pollution, but with peripheral shortcomings of a mainly operational nature. These shortcomings limit the effectiveness to a less than optimal degree.  相似文献   

11.
为防范海外港口工程测量的多种潜在风险,以海外测量项目为背景,总结海外测量项目的主要风险源,并重点 介绍测量标准、控制测量起算资料及测量设备等因素所引发的技术风险。通过原理阐述、横向比较和案例分析,系统阐明 在海外港口测量项目中面临相关问题时所采取的办法以及相应的防控措施, 旨在为从事海外工程测量的技术人员提供借鉴。  相似文献   

12.
For the economic and financial evaluation of port investment projects, it is important to know the demand function of a port's services. The objective of this study is to establish such a demand choice function for the Spanish container port services. The function is derived from the coefficients of a port choice model, for which a multinomial logit model is used and of which the coefficients are estimated with regression analysis. The variables tested concern inland transport cost, ocean transport costs and broad proxy variables for quality of service. Information on container import and export flows for 2007 is obtained from the Spanish Treasury Department. The linear regression analysis is based on differences of utilities of alternative routings of containerised cargoes compared to those routed via the port of Valencia. The obtained results are satisfactory in terms of model fit. The estimated coefficients can be used to assess the impact of changes in costs of container flows routed via a port on a port's market share. A demand choice function for the port can be derived by systematically doing so. An example is presented for the port of Valencia.  相似文献   

13.
港口建设对滨海湿地景观格局的影响及其生态效应   总被引:1,自引:0,他引:1  
对鸭绿江口湿地的土地利用状况进行景观分类,利用TM影像进行人机交互式判读解译,获得了该区域现状和丹东港规划完成后景观解译图,并开展了港口建设对湿地景观格局的影响及其生态效应的评估。结果表明,港口建设后,湿地景观面积几乎没有改变;除了建筑用地斑块数量增加外,其他斑块数量均减少,但变化不明显;湿地景观指数中,香农多样性指数(SHDI)和香农均匀度指数(SHEI)增加,优势度指数(D)和蔓延度(CONTAG)下降,平均斑块分维数(MPFD)几乎没有变化;这些变化表明,湿地的景观格局并没有发生明显变化,因而对生物多样性影响不明显。然而景观的生态服务功能结果显示,港口建设对湿地生态系统造成许多不可逆的影响,导致生态服务功能在一定程度上退化。  相似文献   

14.
为提高港口国监督检查中对人为错误引起的缺陷的重视,通过对人为错误与港口国监督检查关系的分析,提出了在港口国监督检查中实施针对人为错误引起的缺陷的检查方法,以期通过港口国监督的手段来减少由于人为错误引起的海上安全事故的发生,同时保证海上船舶航行安全。  相似文献   

15.
港口与海岸工程结构全生命周期概率设计   总被引:1,自引:0,他引:1  
王元战 《水道港口》2006,27(5):322-328
在港口与海岸工程结构整个生命期内,环境条件和结构系统的状态均会随时间发生变化。结构系统状态变化主要包括:由环境条件作用产生的结构累积损伤(或变形或位移)、钢或钢筋混凝土构件锈蚀、地基冲刷或淤积、地基物理力学指标降低或提高等。文中提出了考虑整个生命周期内环境条件和结构系统状态变化的工程结构全寿命周期概率设计的概念,并结合沉箱式防波堤在长期波浪作用下累积滑移概率分析和考虑钢筋混凝土结构构件抗力随时间变化的钢筋混凝土结构可靠度分析,在工程结构全寿命周期概率设计理论方面进行了初步探讨,为该课题的深入研究提供参考。  相似文献   

16.
杨彩燕  郑凡 《水运工程》2012,(5):113-115
云浮港属于典型的山区型内河港口。通过对云浮港现状特点及存在问题进行分析研究,提出云浮港总体规划的思路及措施,从而研究云浮港空间布局规划方案,为同类型港口的规划工作提供借鉴。  相似文献   

17.
In this paper, a new concept of “port climate risk exposure function along the sea–land boundary axis” is introduced as a critical component towards port adaptation. This concept derived from a global survey which was conducted over 29 countries to assess perceived climate risks to port infrastructure from relevant experts. The methodology used 48 climate scenarios developed based on existing data. Ultimately, this paper serves as a global climate risk indicator to guide further adaptive initiatives in ports.  相似文献   

18.
In this paper are presented the results of a multinomial logit model used to explain the selection of a port for each shipment exported from the US in December 1999. The model is estimated for combined shipments, and one model is estimated for each of four commodity types (bulk, foods, fabrics, manufactured). Results are compared across commodities to find the significance of the distance in either direction, the frequency of sailings, and the average size of vessels sailing along a route. Results of the estimation do not match those that would be expected. Potential reasons are given for such variations, along with numerous methods by which the modelling could be improved. Methods for improvement suggested include structuring of the model to represent more accurately the competitive scenario of each port, constraining the choice set for each shipments from characteristics of the carrier, and the commodity.  相似文献   

19.
In this paper are presented the results of a multinomial logit model used to explain the selection of a port for each shipment exported from the US in December 1999. The model is estimated for combined shipments, and one model is estimated for each of four commodity types (bulk, foods, fabrics, manufactured). Results are compared across commodities to find the significance of the distance in either direction, the frequency of sailings, and the average size of vessels sailing along a route. Results of the estimation do not match those that would be expected. Potential reasons are given for such variations, along with numerous methods by which the modelling could be improved. Methods for improvement suggested include structuring of the model to represent more accurately the competitive scenario of each port, constraining the choice set for each shipments from characteristics of the carrier, and the commodity.  相似文献   

20.
A review of seven large landlord port authorities around the world reveals a notable diversity of pricing structures. While port authorities increasingly act as commercial undertakings, port pricing often seems to be not driven by commercial considerations. In this paper, we argue that ports can be regarded as “business ecosystems” with multiple users. This provides a valuable perspective on pricing and raises the question of whether ports can be regarded as two-sided markets. We argue this is not the case. The business ecosystem perspective provides a basis for deducing seven pricing principles for port authorities that are detailed in the paper and illustrated with cases these principles. These pricing principles are broadly follow a direct user pays approach; capture value from “non-core” tenants; price aggressively for activities with a high strategic value; differentiate pricing based on price elasticity and connectivity improvements; maximize revenue from long-term lease agreements, price port dues competitively; critically consider differentiation of charges based on environmental performance; and finally use incentives to align interests of terminal operators and shipping lines. We conclude that the ecosystem perspective is central to the understanding of pricing decisions of port authorities and that various pricing issues deserve more attention.  相似文献   

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