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161.
This paper, in two parts, reports on the Seaport Development in the European Communities Research Project wherein forty interviews with decision-makers were help in European seaports, and another forty were held with shipowning organization. Respondents were also asked to fill in a questionnaire, and it is these questionnaire, and it is these questionnaire findings that are reported in this the first part of the paper. Expected contrasts between planning philosophies in Britain, Ireland, and Denmark on the one hand and the rest of the EEC on the other were confirmed, and regularity of cargo on offer appears generally belived as the most important factor in route planning of ships. Among other major conclusions (see table 5) are the view that ship congestion at ports is a more scute problem than the over-provision of berths and that short-term low operating costs are considered more important than the security offered by mediumterm plans.  相似文献   
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163.
This paper investigates, for the first time, the relationship between prices and trading activity in a market where real assets are traded, i.e. in the sale and purchase market for second-hand dry bulk vessels. Investigation of this issue is of interest since the level of trading activity may contain information about the sentiment and the future direction of the prices in the market. Several important conclusions emerge from this analysis. It is found that price changes are useful in predicting trading volume, which suggests that higher capital gains encourage more transactions in the market. Additionally, it seems that volume has a negative impact on the volatility of price changes. More specifically, in contrast to what is reported for financial markets, we find evidence that, in the market for ships, increases in trading activity lead to a reduction in market volatility. This can be explained by the unique underlying characteristics of the market for ships, including thin trading, which imply that increases in trading activity result in price transparency and stability. These findings indicate that practitioners in the market may use the information contained in the level of trading activity so as to guide their market decisions in the sale and purchase market.  相似文献   
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165.
The river–sea system consisting of the Gaoping (new spelling according to the latest government's directive, formerly spelled Kaoping) River (KPR), shelf, and Submarine Canyon (KPRSC) located off southern Taiwan is an ideal natural laboratory to study the source, pathway, transport, and fate of terrestrial substances. In 2004 during the flood season of the KPR, a system-wide comprehensive field experiment was conducted to investigate particle dynamics from a source-to-sink perspective in the KPRSC with the emphasis on the effect of particle size on the transport, settling, and sedimentation along the pathway. This paper reports the findings from (1) two sediment trap moorings each configured with a Technicap PPS 3/3 sediment trap, and an acoustic current meter (Aquadopp); (2) concurrent hydrographic profiling and water sampling was conducted over 8 h next to the sediment trap moorings; and (3) box-coring in the head region of the submarine canyon near the mooring sites. Particle samples from sediment traps were analyzed for mass fluxes, grain-size composition, total organic carbon (TOC) and nitrogen (TN), organic matter (OM), carbonate, biogenic opal, polycyclic aromatic hydrocarbon (PAH), lithogenic silica and aluminum, and foraminiferal abundance. Samples from box cores were analyzed for grain-size distribution, TOC, particulate organic matter (POM), carbonate, biogenic opal, water content, and 210Pbex. Water samples were filtered through 500, 250, 63, 10 µm sieves and 0.4 µm filter for the suspended sediment concentration of different size-classes.Results show that the river and shelf do not supply all the suspended particles near the canyon floor. The estimated mass flux near the canyon floor exceeds 800 g/m2/day, whose values are 2–7 times higher than those at the upper rim of the canyon. Most of the suspended particles in the canyon are fine-grained (finer than medium silt) lithogenic sediments whose percentages are 90.2% at the upper rim and 93.6% in the deeper part of the canyon.As suspended particles settle through the canyon, their size-composition shows a downward fining trend. The average percentage of clay-to-fine-silt particles (0.4–10 µm) in the water samples increases from 22.7% above the upper rim of the canyon to 56.0% near the bottom of the canyon. Conversely, the average percentage of the sand-sized (> 63 µm) suspended particles decreases downward from 32.0% above the canyon to 12.0% in the deeper part of the canyon. Correspondingly, the substrate of the canyon is composed largely of hemipelagic lithogenic mud. Parallel to this downward fining trend is the downward decrease of concentrations of suspended nonlithogenic substances such as TOC and PAH, despite of their affinity to fine-grained particles.On the surface of the canyon, down-core variables (grain size, 210Pbex activity, TOC, water content) near the head region of the canyon show post-depositional disturbances such as hyperpycnite and turbiditic deposits. These deposits point to the occurrences of erosion and deposition related to high-density flows such as turbidity currents, which might be an important process in submarine canyon sedimentation.  相似文献   
166.
Measurements of turbulence were performed in four frontal locations near the mouths of Block Island Sound (BIS) and Long Island Sound (LIS). These measurements extend from the offshore front associated with BIS and Mid-Atlantic Bight Shelf water, to the onshore fronts near the Montauk Point (MK) headland, and the Connecticut River plume front. The latter feature is closely associated with the major fresh water input to LIS. Turbulent kinetic energy (TKE) dissipation rate, ε, was obtained using shear probes mounted on an autonomous underwater vehicle. Offshore, the BIS estuarine outflow front showed, during spring season and ebb tide, maximum TKE dissipation rate, ε, estimates of order 10− 5 W/kg, with background values of order 10− 6 to 10− 9 W/kg. Edwards et al. [Edwards, C.A., Fake, T.A., and Bogden, P.S., 2004a. Spring–summer frontogenesis at the mouth of Block Island Sound: 1. A numerical investigation into tidal and buoyancy-forced motion. Journal of Geophysical Research 109 (C12021), doi:10.1029/2003JC002132.] model this front as the boundary of a tidally driven, baroclinically adjusted BIS flow around the MK headland eddy. At the entrance to BIS, near MK, two additional fronts are observed, one of which was over sand waves. For the headland site front east of MK, without sand waves, during ebb tide, ε estimates of 10− 5 to 10− 6 W/kg were observed. The model shows that this front is at the northern end of an anti-cyclonic headland eddy, and within a region of strong tidal mixing. For the headland site front further northeast over sand waves, maximum ε estimates were of order 10− 4 W/kg within a background of order 10− 7–10− 6 W/kg. From the model, this front is at the northeastern edge of the anti-cyclonic headland eddy and within the tidal mixing zone. For the Connecticut River plume front, a surface trapped plume, during ebb tide, maximum ε estimates of 10− 5 W/kg were obtained, within a background of 10− 6 to 10− 8 W/kg. Of all four fronts, the river plume front has the largest finescale mean-square shear, S2 ~ 0.15 s− 2. All of the frontal locations had local values of the buoyancy Reynolds number indicating strong isotropic turbulence at the dissipation scales. Local values of the Froude number indicated shear instability in all of the fronts.  相似文献   
167.
The International Maritime Industry (IMI) is a global web of shipping, connecting all Continents and bringing together mariners from a multitude of national, ethnic and linguistic backgrounds. Wherever humans interact, they communicate in some form or another and the ability to communicate competently is the cornerstone of safety at sea. This paper identifies the growth of English as the lingua franca of the sea, as a framework for the later discussion on current teaching practices. We consider that Maritime English (ME) fits into the category of a special-purpose form of English, in that it has generated, modified or adopted from other languages many terms and phrases that are only used in the IMI. This paper considers safety-to-practice as a factor in curriculum design, teaching and assessment as the basis for ME competence. Further, we propose opportunities to move industry focus forward, through collaboration with stakeholders and discussion about teaching practices. This paper identifies a gap in maritime teaching practices. This paper further explores the use of authentic teaching as a way forward to improve maritime communication.  相似文献   
168.
A precise estimation of vehicle velocities can be valuable for improving the performance of the vehicle dynamics control (VDC) system and this estimation relies heavily upon the accuracy of longitudinal and lateral tyre force calculation governed by the prediction of normal tyre forces. This paper presents a computational method based on the unscented Kalman filter (UKF) method to estimate both longitudinal and lateral velocities and develops a novel quasi-stationary method to predict normal tyre forces of heavy trucks on a sloping road. The vehicle dynamic model is constructed with a planar dynamic model combined with the Pacejka tyre model. The novel quasi-stationary method for predicting normal tyre forces is able to characterise the typical chassis configuration of the heavy trucks. The validation is conducted through comparing the predicted results with those simulated by the TruckSim and it has a good agreement between these results without compromising the convergence speed and stability.  相似文献   
169.
Resource managers are often tasked with identifying and assessing the potential impacts of management actions on the biotic communities under their care. When the management activities directly influence a single species of interest, managers can turn to a variety of models to aid in their understanding of potential changes to that population. However, as ecosystem-based management becomes more widely accepted, managers will have to understand how proposed actions will impact entire biotic communities, through both direct and indirect mechanisms. Thus, there is a need for ecosystem models that account for both trophic and non-trophic interactions, and that can be relatively easily used to assess a variety of management scenarios. We reviewed the available literature regarding incorporation of eutrophication and other anthropogenic impacts into Ecopath with Ecosim (EwE), one of the more widely used trophic ecosystem modeling frameworks. We found that a number of mechanisms of varying complexity have been used to include these stressors in models, providing managers with a suite of options that can be used to complement their existing management options as they seek to understand the impacts of human interactions on the natural environment.  相似文献   
170.
Decades of research has generated new scientific understanding and technologies aimed at better managing environmental change in estuarine and coastal regions. Yet many across the communities of coastal and estuarine research, management, and funding believe that progress has been too slow in applying this research in practice. This essay reviews how the National Estuarine Research Reserve System’s funding program evolved over the past two decades to improve how researchers and users of research work together to increase the uptake of science to achieve resource management and conservation goals. Incremental innovation in the design of the NERRS funding program enabled more intensive and multiway engagement between funders, researchers, and users, which created new pathways for applying science in practice. Furthermore, these interactions stimulate reflection and adaptation within each separate institutional setting, supporting changes that may science to better support environmental problem solving.  相似文献   
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