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31.
康明斯上半年业绩再创历史新高 康明斯公司日前发布二季度财务公报,销售额和利润均创历史最高纪录,美国以外海外市场的迅猛增势有效抵御了美国经济疲软带来的负面影响.  相似文献   
32.
康明斯公司日前发布了三季度财务公报,销售额和利润再创新高。三季度的大好形势主要归因于国际业务的强劲增势,有效抵消了北美消费品市场持续走低和欧洲市场疲软带来的负面影响。康明斯三季度销售额为36.9亿  相似文献   
33.
Plug-in Hybrid Electric Vehicle (Plug-in HEV) has dramatic improvements in fuel economy and emission reduction. It is most important to decide its optimal configuration, energy management strategy, powertrain sizes, and control logic parameters. For multi-objective optimization, we present a concurrent optimization methodology based on an optimal Plug-in HEV powertrain configuration with continuous variable transmission (CVT). The novelty is using evolutionary algorithm in conjunction with an instantaneous optimal energy management strategy. Simulation results indicate the proposed method can significantly reduce fuel consumption and emissions by simultaneously optimizing the propulsion system parameters as well as the energy control parameters.  相似文献   
34.
康明斯公司近日公布了2008年经营业绩,尽管受外部经济衰退的不利影响去年四季度出现滑坡,但全年销售额和利润仍然连续第五年创下历史新高;去年中国区业务继续保持强劲增长态势,占全球业务比重进一步加大;2009年销售额预计较2008年下跌20%,但仍将保持盈利.  相似文献   
35.
康明斯连续第二年入选《财富》"全球最受尊敬企业"排行榜 《财富》杂志日前公布了2009年度"全球最受尊敬企业(World's Most Admired Companies)"排行榜,康明斯公司连续第二年入选,是唯一一家上榜的柴油机公司.  相似文献   
36.
Between January 1990 and March 1995, the research project KERFIX undertook the first regular noncoastal multiyear acquisition of parameters related to the carbon cycle in the Southern Ocean at a time series station located at 50°40′ S–68°25′ E, 60 miles southwest of the Kerguelen Islands. The objectives of KERFIX are (1) to monitor the ocean/atmosphere CO2 and O2 exchanges and to understand which processes govern these exchanges (2) to observe and interpret the seasonal and interannual variability of the production, flux, decomposition and dissolution of carbon and associated elements at this location. In addition, micropaleontological studies describe the present and past flux dynamics in this oceanic area, to improve the knowledge of the transfer functions of some oceanographic proxies. This paper presents a survey of the KERFIX program: scientific objectives, organization of the field operations and some main results obtained since the beginning of KERFIX program, as well as the results of the temporal evolution of hydrological, chemical and biological parameters.  相似文献   
37.
A conceptual framework of individual activity program generation   总被引:1,自引:0,他引:1  
The research in this paper attempts to better understand the process by which activities are generated at an individual level. Activity-based travel analyses have gained popularity in recent years because they recognize the complexity of activity behavior and view travel as a derivative of this behavior. Most activity-based studies have focused on the spatial and temporal linkage of trips; that is, the scheduling of activities. They consider the agenda of activities for participation, and associated attributes of the activity participation (such as mode to activity and location of activity performance), as predetermined. This paper develops a comprehensive conceptual framework of the relatively unexplored area of activity agenda generation. Such a framework will be valuable in empirical modeling of activity generation behavior. A subsequent paper focuses on translating a part of this conceptual framework into an empirical model.  相似文献   
38.
A retrospective and prospective survey of time-use research   总被引:6,自引:3,他引:3  
The central basis of the activity-based approach to travel demand modeling is that individuals' activity-travel patterns are a result of their time-use decisions within a continuous time domain. This paper reviews earlier theoretical and empirical research in the time-use area, emphasizing the need to examine activities in the context or setting in which they occur. The review indicates the substantial progress made in the past five years and identifies some possible reasons for this sudden spurt and rejuvenation in the field. The paper concludes that the field of time-use and its relevance to activity-travel modeling has gone substantially past the "tip of the iceberg", though it certainly still has a good part of the "iceberg" to uncover. Important future areas of research are identified and discussed.  相似文献   
39.
Over the past decades research on travel mode choice has evolved from work that is informed by utility theory, examining the effects of objective determinants, to studies incorporating more subjective variables such as habits and attitudes. Recently, the way people perceive their travel has been analyzed with transportation-oriented scales of subjective well-being, and particularly the satisfaction with travel scale. However, studies analyzing the link between travel mode choice (i.e., decision utility) and travel satisfaction (i.e., experienced utility) are limited. In this paper we will focus on the relation between mode choice and travel satisfaction for leisure trips (with travel-related attitudes and the built environment as explanatory variables) of study participants in urban and suburban neighborhoods in the city of Ghent, Belgium. It is shown that the built environment and travel-related attitudes—both important explanatory variables of travel mode choice—and mode choice itself affect travel satisfaction. Public transit users perceive their travel most negatively, while active travel results in the highest levels of travel satisfaction. Surprisingly, suburban dwellers perceive their travel more positively than urban dwellers, for all travel modes.  相似文献   
40.
Abstract

Since 1990s the liner shipping industry has faced a period of restructuring and consolidation, and been confronted with a continuing increase in container vessel scale. The impact of these changes is noticeable in trade patterns, cargo handling methods and shipping routes, in short ‘operations’. After listing factors influencing size, growth in container ship size is explained by economies of scale in deploying larger vessels. In order to quantify economies of scale, this paper uses the liner service cash flow model. A novelty in the model is the inclusion of +6000-20-foot Equivalent Unit (TEU) vessels and the distinction in costs between single and twin propeller units on ships. The results illustrate that scale economies have been – and will continue to be – the driving force behind the deployment of larger container vessels. The paper then assesses the link between ship size and operations, given current discussions about the increase in container vessel scale. It is found that (a) ship size and operations are linked; (b) optimal ship size depends on transport segment (deep-sea vs. short-sea shipping, SSS), terminal type (transhipment terminals vs. other terminals), trade lane (East-West vs. North-South trades) and technology; and (c) a ship optimal for one trade can be suboptimal for another.  相似文献   
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