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11.
Eric Pels 《Research in Transportation Economics》2008,24(1):68-74
The paper discusses airline network competition. Low-cost airlines and conventional airlines have distinctly different strategies and network types. This determines their ability to compete with other airlines in specific markets. The paper discusses the lack of competition between conventional airlines in local markets, and sees why low-cost airlines are the primary source of competition in such markets. Conventional airlines are relatively strong on long-haul markets, using their networks to keep costs per seat relatively low. Charter airlines show that a long-haul low-cost strategy is feasible For scheduled low-cost airlines, this may be more difficult, but this does not automatically mean that low-cost airlines cannot enter thick long-haul markets. 相似文献
12.
Ecophysiological growth characteristics and modeling of the onset of the spring bloom in the Baltic Sea 总被引:1,自引:0,他引:1
The onset of spring bloom in temperate areas is a transition period where the low productive, winter phytoplankton community is transformed into a high productive spring community. Downwelling irradiance, mixing depth and the ability of the phytoplankton community to utilize the light, are key parameters determining the timing of the onset of the spring bloom. Knowing these parameters would thus provide tools for modeling the spring bloom and enhance our knowledge of ecophysiological processes during this period.Our main objective with this study was to provide data for the growth characteristics of some key species forming the spring bloom in the Gulf of Finland, and to apply those results in a simple dynamic model for the onset of the spring bloom, in order to test if the timing of the spring bloom predicted by the models corresponds to field observations. We investigated the photosynthetic characteristics of three diatoms and two dinoflagellates (Chaetoceros wighamii, Melosira arctica, Thalassiosira baltica, Scrippsiella hangoei and Woloszynskia halophila), at low temperatures (4–5 °C). All of these species are common during spring bloom in the Baltic Sea.Cultures of these species were acclimated to different irradiance regimes prior to measurements of photosynthesis, respiration, pigment concentration and light absorption. We did not find a positive relationship between respiration and growth rate, and we hypothesize that this relationship, which is well established at higher temperatures, is negligible or absent at low temperatures (< 10 °C). Photosynthetic maximum (Pm), and maximum light utilization coefficient (α) was lowest and respiration (R) highest in the dinoflagellates.We made a model of the onset of the spring bloom in the western part of Gulf of Finland, using the obtained data together with monitoring data of mixing depth and water transparency from this area. Model results were compared to field observations of chlorophyll-a (Chl-a) concentration. There was a good agreement between the model predictions and the observed onset of the spring bloom for the diatoms. S. hangoei, however, was not able to reach positive production in the model, and W. halophila had the similar growth characteristics as S. hangoei. Consequently, these species must have other competition strategies enabling them to exist and grow during spring bloom. 相似文献
13.
文中通过对我国沿海港口建设和生产发展状况进行分析,指出了产生码头超能力靠泊的原因,并深入讨论了码头超能力靠泊的危害,最后,从提高码头生产效率、遵守限定条件靠泊核准的新船型等方面提出了解决码头超能力靠泊的方法。 相似文献
14.
This paper develops a model of airport and airline competition in a three-stage game. We analyse incentives for vertical collusion between one airport and one airline that compete with another airport and another airline, by means of static and dynamic games. We find that incentives for collusion exist when airports and airlines have different market sizes and, under certain conditions, also when secondary airports and low cost airlines compete with main airports and full service airlines. 相似文献
15.
刘丽建 《南通航运职业技术学院学报》2011,10(1):15-17,21
文章在文献资料阅读和实地调查的基础上,介绍了海峡西岸港口群基本情况、内部构成及主要港口发展业绩,着重分析港口群在自然条件、经济基础和政策扶持等方面的发展优势和功能单一、内部竞争强等阻碍因素,并提出解决建议,希望能为海峡西岸港口群的进一步规划提供事实依据和帮助。 相似文献
16.
Evangelia N. KaselimiAuthor Vitae Theo E. NotteboomAuthor Vitae Athanasios A. PallisAuthor Vitae Sheila FarrellAuthor Vitae 《Research in Transportation Economics》2011,32(1):71-80
The decision on the scale of a port terminal affects the terminal’s managerial, operational and competitive position in all the phases of its life. It also affects competition structures in the port in which the terminal is operating, and has a potential impact on other terminals. Port authorities and terminal operators need to know the scale of the terminal when engaging in concession agreements. In economic theory the scale of a plant/firm is typically defined in relation to the Minimum Efficient Scale (MES), the long-run output where the internal economies of scale are fully exploited. However, there are a number of theoretical and empirical indications that in ports the scale of a terminal is commonly guided by a combination of the MES and other determining factors. The “preferred” scale is the result of a complex interaction between the MES, the port governance framework and objectives, the market size and structure, technological change and operational considerations, physical and geographical limitations, and the business patterns of shipping lines. This study analyses the factors resulting in a preferred container terminal scale that in most of the times is different from the MES. The analysis of the technical, market-related and governance-related factors is supported by theoretical and empirical insights that illustrate the presence of a range of actual ”preferred” scales of terminal concessions that usually are different, below or above, MES. 相似文献
17.
长期以来,中职学校汽车专业对于技能比赛存在着"重成绩、轻转化"的现象,导致只有少部分教师和学生受益,这与技能大赛"以赛促学、以赛促教、以赛促改"的理念相背。本文以《电控发动机检修》课程为例,阐述了中职学校汽车专业基于技能大赛开展专业核心课程教学改革策略与实践成效,以期为中职学校汽车专业核心课程教学改革提供有益借鉴。 相似文献
18.
港口竞争的市场结构与竞争行为分析 总被引:8,自引:2,他引:6
目前,港口竞争研究已成为一个热点问题。为此,本文首先对港口竞争的范围作了界定,在此基础上,剖析了两种不同类型的港口竞争的市场结构,最后对不同市场结构下的港口竞争行为进行了分析。 相似文献
19.
现代港口建设与运营中的竞争 总被引:2,自引:0,他引:2
从港口所有制形式,港口竞争的层次。影响港口竞争的主要因素等方面,论述了现代港口的主要竞争手段。指出除了地理条件不可改变外,其他条件都可以通过各种竞争手段来实现。竞争与合作是现代港口竞争的新趋势。 相似文献
20.
孙守敏 《上海交通大学学报(哲学社会科学版)》2002,10(1):91-94
作为中国近代重要的启蒙思想家,严复的竞争观对国民的竞争意识发挥了有力的催化作用。严复从进化论的角度揭示了竞争的合理性、进步性、公正性、普遍性、永恒性及残酷性,并将认同竞争和积极参与竞争视为强国强民的根本途径。本探讨了严复竞争观的内在意蕴及其对国民竞争意识的启蒙意义。 相似文献