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1.
The competitive characteristics of the North American seaport industry have, in theory, been causally linked to excess investment and low terminal throughput productivity. This paper empirically examines the link between seaport authority container terminal leasing policy and throughput productivity. Recent advances in inventory theory applied to service industries suggest the pooling of demand uncertainty can yield lower costs without sacrificing customer service. This concept is applied to a container seaport using simulation. The effort compares key output measures from a realistic base case model of the seaport to those generated by an alternative terminal leasing policy. It is shown that the pooling of demand in a common-user seaport reduces total vessel time in port by 17.1% with no reduction in TEU throughput. Throughput productivity is improved for the highest capacity terminals, while lower capacity terminals are made available for additional users or alternative uses.  相似文献   

2.
The competitive characteristics of the North American seaport industry have, in theory, been causally linked to excess investment and low terminal throughput productivity. This paper empirically examines the link between seaport authority container terminal leasing policy and throughput productivity. Recent advances in inventory theory applied to service industries suggest the pooling of demand uncertainty can yield lower costs without sacrificing customer service. This concept is applied to a container seaport using simulation. The effort compares key output measures from a realistic base case model of the seaport to those generated by an alternative terminal leasing policy. It is shown that the pooling of demand in a common-user seaport reduces total vessel time in port by 17.1% with no reduction in TEU throughput. Throughput productivity is improved for the highest capacity terminals, while lower capacity terminals are made available for additional users or alternative uses.  相似文献   

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4.
初步探讨了未来信息化战争的特征和谋略,认为海上空海一体化战争离不开信息化技术的支撑,特别是掌握航天技术大国之间作战,即使在战争第一阶段相互摧毁天基侦察、通讯平台,还需要拓展新的技术领域,发展空基、海基、陆基等平台,构建新的信息网络.中远海战场的C4ISR功能的实现,对广域网络更是特别依赖.海军在中远海执行任务,不一定都是作战,有可能是在非战争情况下保护国家战略大通道和相关海域的国家权益.执行这种任务的技术支撑有新的特色需求和技术保障,文中对潜艇碰撞和防海盗事件作了分析,提出了技术支撑建议.  相似文献   

5.
Increasing commercial and recreational pressures on urban waterfront lands, growing demand by seaports for back-up areas and changes in cargo-distribution concepts have caused the relocation of several port functions and the establishment of inland container terminals.  相似文献   

6.
Port privatization has been perceived as an instrument for the improvement in port management operations and marketing, yet it also provides a major opportunity for public debt reduction by converting debt incurred in port development into equity or other assets. There are many different ways in which debt, particularly foreign debt, can be converted. It can be directly converted into equity, it can be swapped for other debt, converted into various portfolio investments or exchanged for future services or exports. In recent years, 'ecological' swaps have also been considered in which some debt is written off in return for improvements in environmental management. This paper reviews the reasons for port privatization, the different methods for port ownership financing, and the role debt-equity conversion could play in it.  相似文献   

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8.
Traditionally, liner markets have been seen as dominated by conferences on the seller side, facing small, unorganized shippers onn the buyers' side. This perceived asymmetry has greatly influenced conference legislation in North America (and more recently in the E.U.) and it has been deemed essential that government should regulate conference activities in order to curb any abuse of 'conference power'. In this view, shipowners and shippers are adversaries engaged in a zero-sum battle over transport costs rather than potential or actual partners in global distribution systems. This paper suggests that in today's global markets much can be achieved by cooperationn in the development of logistics systems and that shipowners and shippers may have much to gain from such cooperative alliances. A survey of shippers' councils in 1991-1992 demonstrates the diversity and increasing sophistication of many national shippers' councils, which devote themselves to the task of improving markets through education and the legislative process. The situation in the U.S.A. is different: for legal reasons, conventional shippers' councils do not exist. Instead, 'shippers' associations' play a commercial role in liner markets. It is suggested that European style shippers' councils can and should play an important role in the development and formulation of policies for internatinal liner markets. Such participation requires a cooperative industry environment quite different from the traditional adversarial approach, which is ill suited to global trade and logistics alliances.  相似文献   

9.
The Shipbreaking industry has always had a vague image of being 'dirty', 'hazardous' and 'environmatally unfriendly'. As world fleet ages, technology advances and regulations become more stringent, the incidence of shipbreaking activity is set to increase, accompanied by a dispersal of operations bases. The corresponding environmental impacts are, thus, also said to expand commensurately, in magnitude and extent. This coupled with the fact that the shipscrapping is an industry that has a tendency to be located on the shores of the developing countries makes it an environmental tinderbox. The primary reason for this being the lack strict marine environmental regulations in the third world. Neither is the issue addressed at the international forum. The paper addresses the possibilities of the environmental impact of shipscrapping activities. The fact that this part of the shipping industry remains absolutely unregulated, causes a potential detriment to the marine environment. Finally the paper highlights why and what needs to be done.  相似文献   

10.
The free trade agreement (FTA) implemented in 1988 by the United States and Canada will complete the integration of the economics of the world's two largest trading partners. While the vast bulk of US-Canadian trade is transported overland, the FTA will also affect the volume, commodity composition, and spatial distribution of maritime trade. The spatial structure of US-Canadian water-borne trade is examined followed by an investigation of the short-run (non-investment related) impacts of the FTA on the US port system. Commodity-specific analyses of tariffs and non-tariff barriers and elasticities of demand are employed to estimate the sectoral and spatial changes in water-borne trade volumes since 1988 that are attributable to the FTA.  相似文献   

11.
A new automated quality control system for oceanic temperature and temperature–salinity profiles is presented. Substantial development was needed for some of the quality control algorithms although the checks were based on documented procedures used elsewhere where appropriate. A new automated ship track check was developed: the results of an undetected position error can be very damaging to ocean analyses. Also important is a check against a gridded background, this can be a climatology but near the surface it is advantageous to use an estimate that is evolving over time. Bayesian probability theory is used in the background check and the associated check against nearby observations (buddy check). The system was used to process archive data for 1956–2004. As a by-product monthly model-free objective analyses for this period were produced. Versions of the system are used for near-real time ocean analysis and for initialising both short-range ocean forecasts and seasonal atmosphere–ocean forecasts. The main features of the oceanic observing systems are presented along with quality control statistics, examples of errors that can occur and some additional problematic cases.  相似文献   

12.
The development of the LBR-5 “Stiffened Panels Software” is included in the development of a new design methodology to ease and to improve preliminary studies of naval structures and floating hydraulic structures. It allows, as of the first draft, an optimization of the scantling of the structure's constituent elements. The ultimate target is to link standard design tools (steel structure CAD, hull form, hydrostatic curves, floating stability, weight estimation, etc.) with a rational optimization design module and a minimum construction cost (or minimum weight) objective function. It is developed to be a user-oriented tool. The optimization module is composed of three basic modules (OPTI, CONSTRAINT and COST) and a group of sub-modules (in external databases). Among these the user selects a set of relevant sub-modules (i.e. geometrical and structural constraints). Since the present optimization deals with least construction costs (as objective function), and uses an explicit objective function (not empirical), the user must specify labor costs (unitary material costs, welding, cutting, etc.). This paper is the second part of a series of two articles. The previous paper focused on the ‘Module-Oriented Optimization’ methodology and on the rational constraints (Rigo, Marine Structures 2001). This paper presents the optimization algorithm based on convex linearization and a dual approach (OPTI module). It also includes the optimization of a FSO unit as a detailed example.  相似文献   

13.
A high-speed jetfoil service was introduced in 1981 on the Ostend—Dover route. As a 1982-1988 review of operations shows, an average of one flight out of seven is being cancelled. Technical factors are acting in a random manner and, not surprisingly, the reliability of the service is worst in winter-time. It has been but a partial commercial success and its future is threatened by the forthcoming cross-Channel fixed link.  相似文献   

14.
The national-flag fleets of most of the traditional martitime nations have, in virtually every case, been in decline in the 1980s and 1990s, despite the continued growth of ocean shipping. They have declined in terms of numbers of vessels and numbers of sea-going jobs, although not necessarily in terms of cargo carried. However, a number of those nations have responded to the changed technological and competitive conditions with some success by attempting to adjust crewing and work practices on vessels at sea. Neither the USA nor Australia has been in the forefront of such change. However, considerably more progress has been made in modernizing crewing practices and work rules in the Australian-flag fleet than in the US-flag fleet. There are a variety of reasons for this, inluding government policy. However, it is our argument that one of the principal reasons the US fleet lags behind the Australian fleet in the adoption of modern crewing practices and work rules is the much greater degree of union rivalry in the US shipping industry. In fact, while the degree of fragmentation and rivalry among unions in the Australian flag fleet has declined dramatically since 1980, their US cousins have continued, and in some ways expanded, their pattern of fratricidal behavior. First we shall discuss some of the technological and competitive imperatives that are driving human resource management practices in shipping and the crewing and industrial relations adjustments that are being made around the world to adjust to them. Then we shall indicate how the Australian and US fleets have responded to these challenges. This will be followed by a discussion of unionism in the Australian and US maritime industrics as it has devloped in the last two decades of the twentieth century. Finally, we shall draw conclusions about the impact of different patterns of unionization.  相似文献   

15.
The vessel-to-rail intermodal transfer of containers can be performed either within the marine terminal, called on-terminal or outside the marine terminals, called off-terminal. The off-terminal is the common way of rail loading, whereby the marine containers are combined with other, non-maritime containers to achieve greater utilization of yard and rail equipment. The non-terminal transfer, a novelty in US ports, is perceived to be advantageous since it saves on drayage (i.e. haulage) and handling of rail-bound boxes. However, on-terminal has many inherent problems the most critical of them being use of scarce waterfront land, ineffectiveness in mixing international and domestic containers, and large investments required to construct yards and rail accesses. The following article presents a discussion of various aspects of the intermodal, on/off terminal rail-to-vessel alternatives, illustrated by a case study taken from the Port of Long Beach, California.  相似文献   

16.
The Polish economy is going through fundamental changes from a central planning to a market economy. The main aim of this transition is the privatization process which has to change the structure of Polish economy. Privatization has to establish more favourable ways of utilizing the productive capacity of state enterprises and create better conditions to compete on the market. The Privatization process for Polish state enterprises was defined in the Act on the Privatization of State Enterprises of 13 July 1990. According to this Act state enterprises can be privatized in capital or liquidation methods. The capital method has been applied to the privatization of Polish ports. In 1991 the major Polish ports were transformed into a State Treasury shareholder company. The holding company was used in the first stage of privatization. Gdynia was the first port which started this process building the real model of holding. Another important element connected with the structural transformation of Polish ports is the separation of operational and management roles. According to the Act on Ports, the Port Authority is also responsible for the development of the commercial, industrial and distribution services. This Act will also enable Poland to adapt economic and legal regulations which are similar to those in the European Union ports.  相似文献   

17.
Three different versions of a baroclinic three-dimensional circulation model of the North Sea are used to obtain information on the wind and density interactions in the North Sea ROFIs (Regions Of Freshwater Influence): the standard version with fully prognostic treatment of salinity and temperature is compared to a barotropic model run on the same grid on the one hand and to an also fully prognostic model run on a four times coarser grid on the other hand. In order to gain knowledge on the wind and density interactions, two opposing wind directions are chosen for investigation, namely a time of strong north wind, 21st–28th April 1982, and a time of strong southwest wind, 22nd–24th May 1982. In the April case the effect of the salinity gradients on the border of the ROFIs of Rhine, Weser, Ems and Elbe, i.e. along the continental shore, is shown to lead to a clear enhancement of the mean surface currents. In May this result is partly disguised by the additional effect of the thermocline in the deeper parts of the North Sea, i.e. in the classical shelf sea regime region. Nevertheless, the same pattern of enhanced mean surface currents along the coast is detected and is of the same order of magnitude as in the April case. It is thus concluded that although the circulation in the North Sea is reversed by the wind, the density induced component of the general circulation is modified only slightly.  相似文献   

18.
In view of the wide range of estimates for the total primary production for the Southern Ocean south of the Subantarctic Front—current estimates range from 1.2 to 3.5 Gtonne C year−1—we have examined two indirect methods for assessing primary production. First, we have estimated the primary production needed to sustain the carbon requirements of the endotherm top predators in the ecosystem. Estimation of the carbon requirements for crabeater seals of about 7 Mtonne C year−1 is extrapolated to a value for all endotherm predators of 15–30 Mtonne C year−1. Current data indicate that 70–80% of the diet of this suite of predators is zooplankton (predominantly the euphausiid krill), making for highly efficient transfer from primary production to top predators. Our best estimate of Southern Ocean primary production by this method is of the order of 1.7 Gtonne C year−1, or an averaged areal primary production of about 30–40 g C m−2 year−1. Our second approach is to estimate primary production from the drawdown of inorganic nutrients, based on the limited suite of studies from which an annual nutrient deficit can be calculated. Again, this indicates annual primary production of the order of 1.5 Gtonne. Although both methods have inherent uncertainties, taken together they provide a relatively robust constraint on annual primary production. For both methods to underestimate primary production by the 1–1.5 Gtonne C implied by the higher current estimates, carbon export from the Southern Ocean pelagic ecosystem would need to be much higher than is normally found in other oceans.  相似文献   

19.
The effect of the regulation of a carrier's liability by the mandatory application of rules introduced by international convention are considered in the context of a review of the standard terms and conditions employed by major UK passenger carriers reacting to the Athens Convention 1974. It is hoped that by analysing the impact of the Athens Convention upon the British operators who still play a significant part in the international transport of passengers, that light will be shed on the response than can be expected from maritime carriers to the imposition of international convention jurisdiction generally.  相似文献   

20.
Coastal areas such as estuaries, bays and fjords usually have hydrographic characteristics (e.g., temperature, salinity) which differ from those at larger spatial scales and in offshore areas. The differences can arise if the areas are subject to different climatic forcing or if they are relatively isolated from each other due to topographic and ocean circulation features which inhibit advective inputs of water mass properties. Local differences in hydrographic conditions can therefore potentially limit the applicability of existing long time series of coastally monitored temperatures for addressing questions at large spatial scales, such as the response of species distributions and phenologies to climate change. In this study we investigate the spatial synchrony of long-term sea surface temperatures in the North Sea–Baltic Sea region as measured daily at four coastal sites (Marsdiep, Netherlands; Torungen, Norway; Skagens Reef, Denmark; and Christiansø, Denmark) and in several large offshore areas. All time series, including two series reconstructed and intercalibrated for this study (Skagens Reef and Christiansø, Denmark), began during 1861–1880 and continue until at least 2001. Temperatures at coastal sites co-varied strongly with each other and with opportunistically measured offshore temperatures despite separation distances between measuring locations of 20–1200 km. This covariance is probably due to the influence of large-scale atmospheric processes on regional temperatures and is consistent with the known correlation radius of atmospheric fluctuations (ca. 1000 km). Differences (e. g, long-term trends, amplitude of seasonal variations) between coastal temperatures and those measured in adjacent offshore areas varied nonrandomly over time and were often significantly autocorrelated up to 2 years. These differences suggest that spatial variations in physical oceanographic phenomena and sampling heterogeneities associated with opportunistic sampling could affect perceptions of biological responses to temperature fluctuations. The documentation that the coastally measured temperatures co-vary with those measured opportunistically in offshore areas suggests that the coastal data, which have been measured daily using standardized methods and instruments, contain much of the variability seen at larger spatial scales. We conclude that both types of time series can facilitate assessments of how species and ecosystems have responded to past temperature changes and how they may react to future temperature changes.  相似文献   

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