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191.
Y. H. Ki K. J. Lee J. S. Cheon H. S. Ahn 《International Journal of Automotive Technology》2013,14(5):739-745
In this paper, an improved clamping force estimator is proposed for Electro-Mechanical Brake (EMB) systems by using the motor rotor position information and the hysteresis characteristics of mechanical parts in the EMB. A cascaded type of a force/position control system with a force sensor or an estimator was designed and implemented to control the clamping force and to keep the clearance gap in EMB systems. The EMB Hardware-In-the-Loop-Simulation (HILS) results show that the proposed force estimator yields better estimation performance than the existing estimator and that the clamping force control system based on the estimator can be also used for the fault tolerant control of the system. 相似文献
192.
The liner shipping industry has long been characterized by a weekly sailing frequency and schedule unreliability. This research is motivated by the launch of the revolutionary “Daily Maersk” service in late 2011, which introduced daily departures and “absolute reliability” in the Asia–North Europe trade lane. This article analyzes Daily Maersk’s impacts on a shipper’s supply chain inventories and profound implications for the liner shipping industry as a game changer. The quantitative analyses show that the impact of more frequent sailings is most significant on a shipper’s cycle stock, while improving schedule reliability substantially reduces safety stock and pipeline stock. Daily Maersk is most valuable for products that have high value density, high inventory holding cost ratio, low demand variability, and high service level (SL) requirement. These findings imply that the trend of liner alliance/merger/acquisition is likely to continue or even accelerate as shipping lines consolidate fleet capacity to offer more frequent sailings. Rival carriers may step up their involvement in terminal operations to improve schedule reliability. They also need to rethink about their SL targets and clearly define their preferred customer segments. 相似文献
193.
Competition in the business world nowadays is largely between supply chains, rather than individual players only. The same situation exists in container shipping. The study looks into container shipping from an integrated perspective and investigates the nature and level of supply chain integration in container shipping. Based on empirical examinations of the world's top 30 container shipping lines, a scenario analysis is conducted. The paper aims to present the scenario analysis for examining supply chain integration in container shipping. It also aims to formulate strategic recommendations for liners to create and sustain competitive advantage. The scenario analysis is designed to allow more complete consideration of alternative possible outcomes and their implications on the research topic. It involves an evaluation of past and present events and provides a plausible discussion of what might occur in the future. It depicts four scenarios of supply chain integration in container shipping, namely, low integration, partner-focused integration, activity-focused integration and high integration. On the whole, research findings suggest that market situations favour those scenarios representing higher level of supply chain integration. Importantly, with reference to the scenario analysis, shipping lines should position themselves in an appropriate scenario and formulate strategic plans accordingly. 相似文献
194.
Theo E. Notteboom Athanasios A. Pallis Peter W. De Langen Aimilia Papachristou 《Maritime Policy and Management》2013,40(7):636-653
Port economics, management and policy have progressively emerged as a distinctive research field, and a core part of maritime economics. This paper provides an analysis of all the 267 port studies published in Maritime Policy & Management (MPM) since its inception in 1973. This paper provides a content analysis for seven interrelated research theme categories including main research topics and methods, authorship distribution and citation counts. It is demonstrated that MPM played, and continues to play, a key role in publishing research on seaports. The published research increasingly applies established analytical frameworks to ports. The paper concludes with a discussion on current challenges for port-related research. 相似文献
195.
ABSTRACTWe provide two empirical models for calculating the sailing time and berth time of maritime container liner networks to effectively model the ambiguity associated with sea and port contingency for ex-ante decisions of fleet deployment and route planning. The models are based on recorded AIS data of 110 mega vessels including all the operating container mega vessels with a capacity of 16,000 TEU or more during the summer of 2015. The models are able to estimate the sailing time (with R2 of 0.974) and the berth time (with R2 of 0.895) without knowledge of any operational-level explanatory variables. The models are validated against the published East Asia–North Europe services. Moreover, the study reveals that vessel operators adopt different berthing and sailing strategies even under the same conditions. 相似文献
196.
ABSTRACTThe shipping market is volatile. In general, the shipping market cycle shows four stages, through—recovery—peak—collapse, while a upward trend lasts for 7~8 years and a downward trend for another 7~8 years. So the market’s bubble is not sustainable but always ends in a recessionary trend. The economic cycle is common knowledge and an axiom of the shipping industry, but many ship-owners take no account of it. Previous study stated that ship-owners’ fears, triggered by a violently changeable market, make them mimic the crowd mind or herd mentality, following market sentiment. This study aims to measure the effects of herding behavior (HB), triggered by market sentiment, on the shipping market. We attempt to address two research questions: (1) How does HB arise, and what course does it follow? (2) How many vessels (or how many tons) were purchased under the influence of HB? We estimate that 50.5% (227.8 vessels) of the total vessels or 30.4% (3,670.2 tons) of the total tonnage were purchased under the influence of HB. Looking at international finance, we found that ship investment HB is a very strong factor of the recent shipping market, at least in Korea. 相似文献
197.
H. S. Kim M. C. Kim K. S. Choi C. J. Lee 《Journal of Marine Science and Technology》2013,18(4):515-523
A speed sea trial was performed in the Amundsen Sea in February and March of 2012. The Korean ice breaking research vessel “Araon” was used to check speed performance on the big floes. Two of ice trial cases were carried out. We describe the time history of location, the engine power, and the revolutions per minute during the ice trial, and the trajectory of the ship. Additionally, the measured ice properties are considered and discussed. The ice trial results were analyzed according to variation in ice thicknesses, ice strength, propulsion power, and the speed level of the ship. Our analysis results are compared to model test results and ice trial results. A correction to the target ice thickness was used to compare the power and speed relation in the same ice thickness because it is easy to know the relative speed performance of the ship. The Hamburgische Schiffbau-Versuchs Anstalt method was applied for the correction. The speed of Araon in big floes was higher than the speed in level ice. The speed after the correction at 10 MW of power and 103 cm of ice thickness was 5.4 knots based on analysis results. 相似文献
198.
Bart W. Wiegmans 《运输评论》2013,33(5):573-589
Abstract The main objective of this article is to analyse the changes in productivity of the Taiwan Bus Transit System (TBTS) before and after the execution of the ‘Alternatives for Promoting the Development of the Public Transportation Sectors’ (APDPTS), which is designed to provide a better operating environment for the public transport sector in the provision of public transit services. We use a decomposition of the Malmquist productivity index to locate the sources of productivity growth, namely technical change and efficiency change. The former is further decomposed into an output bias, an input bias and a magnitude term to test neutrality. The latter is also decomposed into changes in pure technical efficiency and scale efficiency. In our case, between the pre‐ and post‐APDPTS periods, the efficiency increased only marginally. As a result of a five‐year enhancement programme, the technical regress slowed down slightly, and inward neutral shifts of a transformation frontier were interpreted as being the main contributor to technical regress. In particular, evidence of biased technical change was found, i.e., the effects of output capability increased slightly, but the efficient use of inputs declined during the post‐APDPTS period. 相似文献
199.
This paper proposes the conceptual model of the Asian (Port) Doctrine to explain the successful development of top ranking container ports in Asia during the past four decades. This paper draws a new paradigm for the role of government as a third governance approach in addition to Anglo-Saxon and European doctrines by describing how Asian countries have developed container hub ports by investing in infrastructure as social overhead capital to support export-led growth. We survey characteristics and outcomes in major Asian container port developments and one European port in terms of a port development policy. The findings are presented in a comparative overview of government investment in functional elements of port, maritime infrastructure and landside connections to container ports. This paper confirms that the existing two doctrines—Anglo-Saxon and European doctrines—are not sufficient to explain the Asian success in major container port developments. The proposed framework contends that a newly proposed Asian Doctrine can accomplish this with the help of cross-subsidization, strategic and administered port pricing mechanism. 相似文献
200.