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811.
The impact of diesel vehicles on NOx and PM emissions at various locations in Delhi is assessed using two line source models; the California line source version 4 and the Indian Institute of Technology Line Source. The models offer comparable results but both under predicting the observed values with the Indian Institute of Technology model predictions being slightly better. The analysis also identifies hotspots due to concentrations of NOx and PM and their diurnal variations is found to be greater in at night hours.  相似文献   
812.
This United States stands alone amongst the nations of the world in its attempt to unilaterally regulate transnational ocean linear services. The major reason for current US regularity policies with regard to scheduled ocean transportation lies in its fundamental distruct of any form of co-operation amongst competitors as demonstrated by its history of antitrust legislation.

The linear industry, because of its unique technical and economic charectersitics has given rise to the establishment of ocean conferences—co ordinating sgreements between the operators of linear vessels. Whilst ocean conferences are permitted—even encouraged—by the their most diluted form, the so-called ‘open conferences.

This Paper offers a critical review of Successive US regulatory practices in maritime transport. It is argued that these practices result in excess costs in US trades to the order of $1 billion annually, and that the linear industry‘s efficient functioning is seriously impaired by these rules-rules imposed by a government administration which fails to recognize that the linear industry‘s technical efficiency is of far greater importance than its market performance.  相似文献   
813.
The European Shipping Industry faces a huge capital requirement over the next decade as a result of increasing trade and ageing fleets. This growth in demand is juxtaposed with a contraction in the number of banks willing to support the industry and a general tightening of credit facilities. Consequently, companies have been forced to access the capital markets for equity and debt. The difficulties experienced particularly in the bond markets have lead to premature dismissal of this relatively new form of finance. This paper seeks to explore the suitability of bond finance and finds that it is largely dependent on the perception of the maritime industry by the investment community.  相似文献   
814.
A nonlinear model for unidirectional flow of heavy traffic on a two-lane highway is considered. Features such as entrance, exit and lane transfer with time-dependent parameters are incorporated into the model, with the result that a number of previous models employed in the study of traffic flow become special cases of ours. Using the method of system-size expansion, an asymptotic analysis of the problem, including the time evolution of both deterministic and stochastic aspects of the traffic system, is carried out. In addition, a scheme for obtaining the moments of the probability distribution for systems of finite size is developed and a comparison is made with the exact results appropriate to a particular model. The agreement between the two sets of results turns out to be remarkably good.  相似文献   
815.
In order to study the influence of wind mixing on the spring variability of the plankton production of the north western Corsican coastal area, a one-dimensional (1D), vertical, coupled hydrodynamic/biological model (ECOHYDROMV) is used. A hydrodynamic 1D model of the water column with a kl turbulent closure is applied. The biological model comprises six state variables, representing the plankton ecosystem in the spring period: phytoplankton, copepods, nitrate, ammonium, particulate organic matter of phytoplanktonic origin and particulate organic matter of zooplanktonic origin. The system is influenced by turbulence (expressed by the vertical eddy diffusivity), temperature and irradiance. The model takes into account momentum and heat surface fluxes computed from meteorological data in order to simulate a typical spring atmospheric forcing for the considered area. Results show that primary production vertical structure is characterised by a subsurface maximum which deepens with time and is regulated by the opposite gradients of nitrate concentration and irradiance. Surface plankton productivity is mainly controlled by turbulent vertical transport of nutrients into the mixed layer. The short time scale variability of turbulent mixing generated by the wind appears to be responsible for the plurimodal shape of plankton blooms, observed in the considered area. Furthermore, the model is applied to the study of the spring evolution of the plankton communities off the bay of Calvi (Corsica) for the years 1986 and 1988. In order to initiate and validate the model, time series of hydrological, chemical and biological data have been used. The model reproduces accurately the spring evolution of the phytoplankton biomass measured in situ and illustrates that its strong variability in those years was in close relation to the variability of the wind intensity.  相似文献   
816.
This study estimates the willingness-to-pay value for a one dB(A) change over a range of initial noise levels for a sample population in Hong Kong. It establishes a protocol for estimating the willingness-to-pay values by first establishing an annoyance–dB relationship. The protocol takes into account the characteristics that the probability of being annoyed at a particular level varied with the initial objective noise level, and the annoyance–dB relationship varied for a range of initial annoyance level. The study shows that household income level and initial annoyance levels exert considerable influences on the individual’s willingness-to-pay values. However, age and educational level were found not to exert any significant influence on individual’s willingness-to-pay values.  相似文献   
817.
Tolerance design of vehicle suspension is an important factor that affects the ride and handling quality and cost of the vehicle. Also, applying geometric tolerance to an analysis model is found to be a difficult process. This paper presents a method for tolerance analysis of wheel alignment of vehicle suspension. Monte-Carlo simulation method is applied to multibody elasto-kinematic model to analyze the accumulated geometric tolerances. As an example, Macpherson Strut Type front half car model is used, and wheel alignment dispersion and contribution ratio to the dispersion by accumulated geometric tolerances is computed. This paper also presents an efficient modeling and analysis method for elasto-kinematic model of vehicle suspensions by computing the stiffness matrix analytically. The simulation results of a Macpherson Strut Type demonstrates the validity and accuracy of the proposed method.  相似文献   
818.
The European Shipping Industry faces a huge capital requirement over the next decade as a result of increasing trade and ageing fleets. This growth in demand is juxtaposed with a contraction in the number of banks willing to support the industry and a general tightening of credit facilities. Consequently, companies have been forced to access the capital markets for equity and debt. The difficulties experienced particularly in the bond markets have lead to premature dismissal of this relatively new form of finance. This paper seeks to explore the suitability of bond finance and finds that it is largely dependent on the perception of the maritime industry by the investment community.  相似文献   
819.
820.
The primary aim here is an attempt to measure the impact of foreign exchange movements on the operating results of the shipping industry. The issue arises from the imposition of a volatile foreign exchange market on a freight market structure which fixes revenues in US dollars. Despite attempts to shift costs into dollars, some other currency liabilities still remain, making exposure to exchange rate fluctuations inevitable. The contemporary experience of the Norwegian industry is used to analyse the cost structure in terms of currency denomination, the volatility in the real Kroner/US dollar exchange rate, and the sensitivity of the operating results to these fluctuations. This serves to highlight the commercial vulnerability of shipping companies. Exposure can be seen in a positive or negative light depending on the direction of movement in the exchange rate. Operating profits can rise and fall dramatically simply because of these exchange rate movements.  相似文献   
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