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931.
A prominent feature of modern day piracy is the ransom that is demanded for the safe release of the ship, cargo and crew. The recent upsurge of this type of piracy, in areas of the world that are of strategic importance to the shipping industry, has created many challenges for shipowners, underwriters and the law relating to marine insurance. The aim of this paper is to examine how the marine insurance market is being affected by the threat of modern day piracy, and seeks to identify the options that are available for the recovery of a ransom payment by the shipowner. Moreover, this study aims to identify the legal issues that might prevent a shipowner from recovering a ransom payment under an insurance policy or from the other interests in a common adventure. The study establishes that a reasonably made ransom payment by the shipowner will amount to an extraordinary expense that is taken to minimise or avert a loss. Such an act can generally be recovered under the insurance policy as a sue and labour expense or from other interests in the common adventure as a general average expense. However, illegality, unseaworthiness and exemption clauses in a marine policy are identified as being legal issues that may prevent a shipowner from recovering the ransom payment. Some of these problems may be overcome if clauses are carefully drafted to specifically cater for modern day piracy in a marine insurance policy. Several inconsistencies may also be resolved by transferring the piracy peril to war risks cover. The shipowner’s duty is to respond to the changing circumstances, by ensuring that his vessel is sufficiently equipped and the crew is properly trained to resist a hijacking.  相似文献   
932.
933.
This study develops a gradient-sensitive driving cycle for vehicles in military areas with paved and unpaved roads over steep and undulating terrain. The methodology develops the driving cycle using micro-trips extracted from real-world data taking into account factors that affect fuel consumption. The accuracy of cycle depended on the root mean square error and information value.  相似文献   
934.
Urbanization and demands for mobility have spurred the development of mass rapid transit infrastructure in industrializing Asia. Differences between the character of pre-existing urban structure in these localities and worldwide precedents suggest a need for studies examining how new rapid transit systems function locally. This study of Bangkok’s elevated and underground rail systems identifies relationships between the built environment and pedestrian behavior surrounding stations. Based on details of 1,520 pedestrian egress trips from three elevated and three underground stations in 2006, multiple regression and analysis of variance (ANOVA) revealed that types of pedestrian destinations, reflecting land uses, were related to length of walking egress trips. Trips to shopping centers and office buildings were longer, while trips to eating places were shorter. The most common type of pedestrian trip recorded was to another vehicle, and trips to automobile taxis and motorcycle taxis figured prominently. Policy implications of the findings are considered.  相似文献   
935.
The collapse of the ventilated cavitation occurring on a cylindrical vehicle during the water-exit is numerically researched. The numerical model employs the finite volume method to solve the multiphase Reynoldsaveraged Navier-Stokes (RNNS) equations and uses the volume of fluid (VOF) method to capture the free surface. A practical water wave environment that the vehicle usually encounters is reproduced in a numerical wave flume, so that the water wave’s effect on the cavity collapse flow regime is investigated. The main feature of the waterexit collapse of a ventilated cavity is studied under the wave-free condition. The result indicates that a collapsing ventilated cavity experiences two stages, in which the pattern of cavity evolution is different. In the early stage, the cavity undergoes a rapid shrinkage as a closed body. In the late stage, the cavity releases gas from the front due to the increase of the cavity pressure. The water wave effect is investigated at three typical wave phases: the wave crest, the wave trough and the wave node. Results show that when the vehicle is launched under the wave node, the cavity collapse regime remains fairly axisymmetric and is similar to the wave-free case. However, when the vehicle is launched under the wave crest and trough, the cavity evolution presents highly three-dimensional (3D) features. The results of predicted cavity size, pressure distributions and hydrodynamic forces at different wave phases show that the wave effect is relatively weak at the wave node but becomes apparent at the wave crest and trough.  相似文献   
936.
This paper presents theoretical analysis of unconventional forging process of hollowed shaft from Ti-6Al-4V alloy in a three-slide forging press. This method in comparison with other metal forming methods allows for obtaining of hollowed products. The designed process is verified theoretically by means of numerical simulations based on finite element method with assumption of 3D state of strain. The following factors are considered in the analysis: material flow kinematics, strain distribution, temperature distribution and force of process. On the basis of results, it is stated that the application of designed technology allows for obtaining of a product of assumed quality. A comparison is made between material consumption in analyzed process and material consumption in typical metal forming methods, also in used at present technology of shaft manufacturing by machining only. It is stated that the application of forging in the three-slide forging press allows for a considerable decrease of manufacturing costs due to material savings and decrease of labor consumption of operations at finishing.  相似文献   
937.
In this paper, a 3D time domain technique is adopted to calculate the coupled hydrodynamic interaction between two bodies without flare in waves. For verifying the code, two same cylinders are selected to calculate coupled hydrodynamic effects by comparison with the results obtained by 3D frequency method which has been proved to be efficient for solving such problems. In order to improve efficiency of calculation, the effect of history time has been discussed, and an improved method is presented. Moreover, the effect of lateral separation distance is also discussed in detail. The technique developed here may serve as a more rigorous tool to analyze the related transient problems of two ships doing underway replenishment in waves.  相似文献   
938.
Application of data fusion method to fault diagnosis of nuclear power plant   总被引:1,自引:0,他引:1  
The work condition of nuclear power plant (NPP) is very bad, which makes it has faults easily. In order to diagnose the faults real time, the fusion diagnosis system is built. The data fusion fault diagnosis system adopts data fusion method and divides the fault diagnosis into three levels, which are data fusion level, feature level and decision level. The feature level uses three parallel neural networks whose structures are the same. The purpose of using neural networks is mainly to get basic probability assignment (BPA) of D-S evidence theory, and the neural networks in feature level are used for local diagnosis, D-S evidence theory is adopted to integrate the local diagnosis results in decision level. The reactor coolant system is the study object and we choose 2# steam generator Utubes break of the reactor coolant system as a diagnostic example, The experiments prove that the fusion diagnosis system can satisfy the fault diagnosis requirement of complicated system, and verify that the fusion fault diagnosis system can realize the fault diagnosis of NPP on line timely.  相似文献   
939.
In the conceptual stage the function design process is realized by the computer aided application. After surveying on the function specification methods and the function modeling, a computer aided function design environment is analyzed. Subsequently based on a module library and principle catalogue, a solution finding process as a part of conceptual design is proposed for a creative design. In addition, a search algorithm to find the solution of adaptable function structure is also discussed. The concepts proposed in this paper can support the subsequent design stages, especially simulation for checking the function structure defects.  相似文献   
940.
The digital signal-obtaining for gyroscope is given. The single optic-fiber sensor via modulating intensity of light is used as measuring eonlponent . The influence on static transmission properties resulting from the special working environnlent (e. g. cryogenic and vacuum) ,the measure error because of tile reflector shape of rotor,the abnormity of facula from sensor caused by the existence of engraving error,and tile fixing error of sensor and the error of machine tool's initial lignnlent are investigated. The mathematic model in every condition is founded, the simulation and relative experiments ale done and the outeome is analyzed. The mathematic model and method of compensating technology are studied and some relative experiments are made. The result of study is usefid to improvement of the signal-obtaining system.  相似文献   
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