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381.
382.
Hui Ding Haigen Xu Jun Wu W. J. F. Le Quesne C. J. Sweeting N. V. C. Polunin 《Coastal management》2013,41(5):443-457
Marine ecosystems of the East China Sea are rich in biodiversity, with 12,933 species of which approximately 47.7% are endemic. As anthropogenic impacts are intensifying, fishery resources and biodiversity in the East China Sea are under threat from overfishing, habitat loss, pollution, and biological invasions. Marine protected areas (MPAs) and other spatial management measures are believed useful tools to protect and restore biological resources. Seventeen nature reserves, seven special marine reserves, and three fishery resource conservation zones covering a combined area of 102,156 km2 have so far been established in the Chinese East China Sea in order to protect fishery resources, biodiversity, and marine landscapes. This article provides a review and inventory of MPAs in the Chinese East China Sea as implemented by the People's Republic of China. 相似文献
383.
Abstract The recently adopted Law of the Sea (LOS) Convention contains a provision allowing coastal nations to adopt 12‐mile territorial seas. Already 104 nations (of a total of 137 coastal nations) have claimed territorial seas of 12 miles or wider. The paper discusses the factors which, in the opinion of the authors, could cause the United States to broaden its territorial sea from the present 3 miles to 12 miles within the next half‐dozen years or so. The state‐federal ocean use and resource management issues that will be raised by such a move are reviewed and options for dealing with the jurisdictional issues are developed. Given the political and economic volatility of these issues and their complexity, the use of a broadly representative and well‐staffed study commission to formulate a course of action is suggested. 相似文献
384.
J. K. Kim Y. J. Kim W. H. Yang Y. C. Park K.-H. Lee 《International Journal of Automotive Technology》2011,12(3):375-381
This study proposes a structural design method for an outer tie rod installed in a passenger car. The weight of the outer
tie rod is optimized by using the aluminum alloy Al6082M, which is developed as a steel-substitute material, and applying
structural optimization techniques. The high strength aluminum with improved mechanical properties was developed to reduce
the weight of the outer tie rod. The newly developed aluminum alloy Al6082M is applied as the material of the outer tie rod.
The static strength due to inertia force, durability and buckling performances are considered in the structural design of
the outer tie rod. At the proto design stage of a new outer tie rod, it is cost-effective to utilize FE (finite element) analysis
to predict each of these performances. In addition, the current trend in the structural design of automobile parts is to use
optimization techniques to reduce the weights of the parts. First, for an arbitrary base design, the static strength, the
life cycle and the buckling load are calculated to check whether the design satisfies its criteria. Then, the critical performance
is selected so as to include its loading condition only in the optimization process. In this study, the metamodel based optimization
process using kriging is adopted to obtain the minimum weight satisfying the critical design requirement. Then, the feasibility
of the determined optimum shape is investigated against the other performances. Finally, the optimum design of outer tie rod
is modified by considering forging efficiency. The performances of the final design are investigated through simulation and
experiment. 相似文献
385.
Valve seats press-fitted in the cylinder head function to hold exhaust gas inside the ignition chamber and to transfer heat to the coolant moving in the water jacket of the head. The press-fitting of the valve seats to the head at ambient temperature has been widely spread out due to its many advantages over pressing with frozen valve seats or with a heated head. The benefits include lower equipment costs, lower running costs, and fewer installation faults during the press-fitting. Nevertheless, a systematic approach for pressing at ambient temperature (ATP; ambient temperature press-fitting) has not been studied and analyzed to date. A technique to check the reliability of the press-fitting by measuring hoop strain inside the valve seat and the FEM procedure to simulate ATP is developed in this study. The FEM procedure of ATP developed here exhibits a concurrence with experimental results. Utilizing the DOE (Design of Experiments) technique, we determined the effects of various geometric parameters and the optimal shapes of the valve seat and cylinder head. The optimal shapes have been successfully applied in an actual engine and varified in a running-engine test. 相似文献
386.
S. W. Lee Y. S. Cho W. C. Choi J. H. Lee Y. J. Park 《International Journal of Automotive Technology》2012,13(7):1149-1157
This study aims to investigate the combustion characteristics of mixed fuel of liquefied propane gas (LPG) and biodiesel under compression ignition (CI) in an effort to develop highly efficient and environmentally friendly mixed fuelbased CI engines. Although LPG fuel is known to be eco-friendly due to its low CO2 emission, LPG has not yet been widely applied for highly efficient CI engines because of its low cetane number and is usually mixed with other types of CI-friendly fuels. In this study, a number of experiments were prepared with a constant volume chamber (CVC) setup to understand the fundamental combustion characteristics of mixed fuel with LPG and biodiesel in two weight-based ratios and exhaust gas recirculation (EGR) conditions. The results from the current investigations verify the applicability of mixed fuel of LPG and biodiesel in CI engines with a carefully designed combustion control strategy that maximizes the benefits of the mixed fuel. Based on the results of this study, ignition is improved by increasing the cetane value by using higher blending ratios of biodiesel. As the blending ratios of biodiesel increased, CO and HC decreased and CO2 and NOx increases. 相似文献
387.
Ever increasing demand for the petroleum is causing faster than expected oil shortages in the supply and demand balance around
the world and furthermore, many specialists in the field of oil production such as Association for the Study of Peak Oil and
World Energy Outlook are claiming that the petroleum is around the peak of its production (Figure 1). Such shortage made the
greatest impact on the gasoline price hikes at the gas pump and thus, this impact was felt by the consumers severely and became
the greatest motivation for automotive industries to strive to pioneer the researches for the next generation vehicle configurations
ranging from HEV, PHEV, Pure EV to FCHEV (collectively noted as xEV). While the great deal of researches has been carried
over the last few decades, it is still far from mass productions for consumer use except for the HEV mainly due to the high
cost involved with other types of xEV configurations. Therefore, it is critical to design the vehicle to maximize the use
of each component at its highest point regardless of any cost scenarios and it is clear that this optimization can only be
achieved through the accurate energy balance simulation for a specific target vehicle prior to the actual hardware implementation.
In this paper, it is our intention to introduce modified dynamic battery modeling scheme that would provide a more accurate
way of simulating the battery behavior when used in the vehicle energy simulation system. Starting from a typical battery
dynamic model to predict the voltage given an imposed current request, we have introduced a new scheme to establish the relationship
between the voltage and the power (rather than the current) requested by the vehicle simulation system. The proposed scheme
handles the power request from the vehicle simulator considering the dynamic battery characteristics and in turn, contributes
to the better estimation of the current integrated energy usage and battery SOC level in the given battery dynamic system
used in the vehicle energy simulation system. 相似文献
388.
C. H. Zheng Y. I. Park W. S. Lim S. W. Cha 《International Journal of Automotive Technology》2012,13(3):517-522
The fuel economy of a fuel cell hybrid vehicle (FCHV) depends on its power management strategy because the strategy determines
the power split between the power sources. Several types of power management strategies have been developed to improve the
fuel economy of FCHVs. This paper proposes an optimal control scheme based on the Minimum Principle. This optimal control
provides the necessary optimality conditions that minimize the fuel consumption and optimize the power distribution between
the fuel cell system (FCS) and the battery during driving. In this optimal control, the final battery state of charge (SOC)
and the fuel consumption have an approximately proportional relationship. This relationship is expressed by a linear line,
and this line is defined as the optimal line in this research. The optimal lines for different vehicle masses and different
driving cycles are obtained and compared. This research presents a new method of fuel economy evaluation. The fuel economy
of other power management strategies can be evaluated based on the optimal lines. A rule-based power management strategy is
introduced, and its fuel economy is evaluated by the optimal line. 相似文献
389.
In this paper, a numerical procedure to estimate the performance of the high power pretensioner used in the seatbelt of a
passenger vehicle is presented. The data on the gas explosion pressure in a 10-cc volume and the data on the displacement
of the rack according to time were applied to the numerical procedure. The procedure was implemented using MATLAB. The testing
device, which met the automobile industry standards, was created. Experiments were carried out seven times under the same
conditions, and the mean values of the web retraction and belt load were used as the representative data. By comparing the
simulation results to the test results, the numerical procedure presented in this paper was verified. 相似文献
390.
W. H. P. Canner 《Maritime Policy and Management》1981,8(3):191-196
This paper examines the depth of air-cargo market penetration being made in the UK by the air-transport industry, following the collapse of I.A.T.A.-constructed fares a nd rates in the wake of de-regulation on the US domestic market in 1978.
It looks at statistical evidence from H.M. Customs and Excise for 1978, 1979 and 1980, and in particular makes a distribution costs analysis by comparing sea and air costs together. In the current economic climate, given today's freight rates and the fact that air-freight is rapidly turning towards bulk unitization with a frequent scheduled delivery service, a reassessment of company distribution costs could be financially beneficial to many exporters traditionally using sea transport. 相似文献
It looks at statistical evidence from H.M. Customs and Excise for 1978, 1979 and 1980, and in particular makes a distribution costs analysis by comparing sea and air costs together. In the current economic climate, given today's freight rates and the fact that air-freight is rapidly turning towards bulk unitization with a frequent scheduled delivery service, a reassessment of company distribution costs could be financially beneficial to many exporters traditionally using sea transport. 相似文献