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41.
This article formalizes the land use design problem as a discrete-convex programming problem integrating within a quadratic assignment framework a realistic representation of transportation behavior (automobile congestion and variable demand for travel) as modelled by a combined trip distribution trip assignment model. Hill-climbing algorithms are proposed to solve the resulting optimization problem. Their performance is compared and evaluated on a set of test problems. 相似文献
42.
Sang Hyeop Lee Suk Lee Man Ho Kim 《International Journal of Automotive Technology》2018,19(5):837-844
An advanced driver assistance system (ADAS) uses radar, visual information, and laser sensors to calculate variables representing driving conditions, such as time-to-collision (TTC) and time headway (THW), and to determine collision risk using empirically set thresholds. However, the empirically set threshold can generate differences in performance that are detected by the driver. It is appropriate to quickly relay collision risk to drivers whose response speed to dangerous situations is relatively slow and who drive defensively. However, for drivers whose response speed is relatively fast and who drive actively, it may be better not to provide a warning if they are aware of the collision risk in advance, because giving collision warnings too frequently can lower the reliability of the warnings and cause dissatisfaction in the driver, or promote disregard. To solve this problem, this study proposes a collision warning system (CWS) based on an individual driver’s driving behavior. In particular, a driver behavior model was created using an artificial neural network learning algorithm so that the collision risk could be determined according to the driving characteristics of the driver. Finally, the driver behavior model was learned using actual vehicle driving data and the applicability of the proposed CWS was verified through simulation. 相似文献
43.
评价是语篇意义的一个核心成分,可以出现在语篇的任何地方.评价的实现方式存在显性与隐性之别,它不仅可以借助评价词汇显性表达,也可以通过其它途径隐性暗示.文章通过探究评价显明性的本质,认为语境和价值观在隐性评价的解读过程中发挥了重要作用.同时,文章探讨了影响语篇评价显明程度的因素,这些因素包括语篇体裁、评价处所和交际双方的... 相似文献
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Ji Hyun Yang Sang Yeong Choi Kang Park 《International Journal of Automotive Technology》2018,19(5):915-922
This paper proposes a systematic framework for operability evaluation of remotely controlled ground combat systems (RGCS) in a simulated environment. The popular human-robot interaction metric used in unmanned vehicle systems is called fan-out (FO) and represents the maximum number of robots/vehicles that could be controlled by a single human operator. However, FO is inappropriate for systems with a lower level of automation where vehicles are remotely controlled by a human, such as RGCS. The theoretical background of the suggested framework is based on McRuer’s crossover model that was initially developed in the aviation domain for explaining pilot handling issues. In this study, an evaluation/analysis software prototype was developed, known as the RGCS operability evaluation tool in a simulated environment (ROPES). The ROPES was designed to be a simple tool for use by officers or researchers who only have intuitive understanding on the human adaptability. The ROPES includes two sub-modules; 1) an interactive interface for the configuration of the RGCS dynamic parameters and user interfaces and 2) a time-varying graphical display of system and human performance. Examples case studies demonstrate the advantage of the ROPES, and improvement points were identified for future development. 相似文献
46.
Cheol Woong Park Chang Gi Kim Young Choi Sun Youp Lee Sung Won Lee Ui Hyung Yi Jang Hee Lee Tae Min Kim Duk Sang Kim 《International Journal of Automotive Technology》2017,18(6):1061-1066
Natural gas fuel, as an alternative energy source of transportation, has been used widely since it has an advantage of low emission levels. However, new technologies are required in order to meet the reinforced emission regulations. For this purpose, research into the development of hydrogen-compressed natural gas (HCNG) blend engine was carried out to evaluate its feasibility and emission characteristics. The Engine Research Department at the Korea Institute of Machinery and Materials carried out a large number of tests based on various parameter changes that could affect the performance and emission of HCNG engine in different operating conditions. An earlier stage of the research project focused on the lean combustion of a HCNG engine for heavy duty vehicles to meet the EURO-VI standards. An 11-L/6-cylinder CNG engine was used for the test. The effects of the excess air ratio change were assessed based on various content ratios of hydrogen in the natural gas fuel. In the later part of the HCNG research, a stoichiometric mixture operation was suggested to meet reinforced emission regulation without requiring a De-NOx system. Additionally, an exhaust gas recirculation (EGR) system was introduced for the purpose of improving thermal efficiency and durability. The optimal operating conditions were selected to achieve the best thermal efficiency to meet the required emission levels. In this paper, we demonstrate that a HCNG engine can achieve a significant decrease in NOx emissions, as compared to that of a CNG engine, while meeting the requirements of the EURO-VI standards during a transient mode cycle test. EGR can suppress the weakness of stoichiometric mixture combustion strategy, such as the deterioration of the durability and thermal efficiency, while the emission level can be lowered with the use of a three-way catalyst. The possibility of further reduction of emissions and CO2 with EGR was evaluated to access practical application of a HCNG engine in the field. From that evaluation, the HCNG engine with stoichiometric mixture operation for heavy duty vehicles was developed. The emission levels of HCNG engine were 50 % lower when compared to the EURO-VI standards with a greater than 10 % decrease in CO2 compared to that of a natural gas engine. 相似文献
47.
桑保军 《兰州交通大学学报》2005,24(5):30-33
道德不仅是现实的社会规范,它还包含着人们对理想社会生活的美和善的价值追求.法治的道德性是从法治的内外方面探讨法治对于善和美的科学体现和发展,权利则是法治道德性的生命.对法治道德性的关注有助于推动我们社会法律化道德的构建和法治文明的实现. 相似文献
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Recent observations of hydrography, currents and volume transports in the straits of the East/Japan Sea are reviewed. It is newly found that bottom cold water in the Korea/Tsushima Strait originating from the northern region of the East/Japan Sea appears not only in summer and autumn but also in winter. Intensive observations in the Korea/Tsushima Strait revealed two distinct cores of northeastward currents in the upper layer of the western and eastern channels. Mean volume transport through the Korea/Tsushima Strait is calculated as 2.5 ± 0.5 Sv from four-year direct and indirect measurements. As continuous monitoring has started in the Tsugaru and Soya Straits, understanding of temporal variability of currents and volume transports through the straits is in progress. For the first time, simultaneous time series of volume transports are available in the Korea/Tsushima and Tsugaru Straits during the winter of 1999–2000. Ouflow through the Tsugaru Strait accounts for about 70% of inflow through the Korea/Tsushima Strait for this period. 相似文献
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