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21.
ABSTRACTe-Transformation in container ports means port organization-wide innovative transformation encompassing internal and external value chains based on information and communication technology. There is a considerable theoretical literature on the impact of e-Transformation on business performance, but there is very little empirical study on its effectiveness in ports. The objective of this paper is to empirically investigate how e-Transformation in container port management can influence customer satisfaction and port competitiveness. The findings reveal that e-Transformation in container ports can affect customer satisfaction and port competitiveness through e-Workplace, customer relationship management and security, implying that container ports should make every effort to focus on e-transformation in these critical areas. Due to limited empirical studies in this area, the findings have provided an empirical support for the importance of e-Transformation in container terminal management and shed more light on how e-Transformation can affect customer satisfaction and port competitiveness. 相似文献
22.
With the continuous growing of the aquaculture industry and increasingly limited fish farming sites at close to shore areas both in Norway and worldwide, there is a need to develop fish farms suitable for aquaculture production in typical offshore environments. For this purpose, SALMAR has developed and deployed the Ocean Farm 1 facility for offshore fish farming.The main purpose of this paper is to develop a reliable numerical model and investigate the motion responses of the Ocean Farm 1 structure in waves and current. The established numerical model consists of the Ocean Farm 1's frame structure (with rigidly-connected circular column components), the net and the mooring system. The hydrodynamic external loads and coefficients of the frame structure are obtained by using potential flow theory. The quadratic drag load on the individual circular columns of the frame structure is formulated by a given drag coefficient. The loads on the net are formulated by using the screen model, where the Reynold number dependent lift and drag forces are formulated as a function of the solidity ratio Sn of the net, relative inflow angle and velocity. The hydrodynamic loads on the mooring lines are formulated using the Morison's equation and the structural responses of the mooring lines are obtained using a nonlinear FE model.With the developed numerical model, time domain simulations are performed. The simulation results are firstly validated against measured data from the decay tests, current tests, and regular wave tests. After the validation, numerical simulations are performed in different irregular wave and current combined weather conditions and the obtained motion response of Ocean Farm 1 are discussed and compared with available measurement data. 相似文献
23.
An altimeter data assimilation scheme has been tested in the OCCAM (Ocean Circulation and Climate Advanced Modelling) global 1/4°, 36-level model using a twin experiment format. The Cooper and Haines displacement scheme is used. The method works well in most regions and depths. Currents and densities in the top 1000 m generally improve by over 50–70% after 5 months of sea level assimilation every 15 days. Below 1000 m, an error reduction of up to 50% is achieved. The errors remain low during a further 60-day run without assimilation. Diagnostics for the North Atlantic, the Tropical Pacific and the Antarctic Circumpolar Current are shown alongside the global averages.The main problems encountered were in weakly stratified regions of the Antarctic and Arctic seas. A scale selective filter is developed to avoid assimilating scales much larger than the local deformation radius, and this avoids the adverse assimilation effects in the southern oceans. A companion paper uses this scheme to assimilate TOPEX and ERS-1 altimeter maps. 相似文献
24.
Junbo Jia 《Journal of Marine Science and Technology》2007,12(1):43-57
To reduce the area on deck occupied by each car and the labour and time required for lashing and unlashing cars, it has been
proposed by the author that in some conditions, cars on decks could be transported without lashing. To evaluate cargo securing
based on this “lashing-free” concept, computational code was developed to calculate the vehicle–deck interactions for various
ship motions. The code was structured by incorporating a vehicle model into a piece of ship motion calculation code. A series
of time-domain simulations were conducted to evaluate vehicle securing. It was found that for a target ship consisting of
a 6000-unit Ro-Ro vessel, vehicle securing is mainly influenced by the ship's rolling motions and is highly dependent on the
wave height and loading conditions. It was suggested from the analysis that vehicles could be secured without being lashed
in a large area of the ship in specific weather conditions and on some routes with less adverse sea states. However, it is
still suggested that conventional lashing holes should be constructed on the deck because in severe sea states the cars will
still need to be lashed. The limitations of the current investigations are also presented.
The relevant research work was carried out at the Division of Ship Design and Engineering, Department of Shipping and Marine
Technology, Chalmers University of Technology. 相似文献
25.
26.
城市人行天桥美学造型简析 总被引:1,自引:0,他引:1
陈正斌 《重庆交通学院学报》2007,26(4):120-123
主要阐述城市人行天桥的造型与景观的关系,城市人行天桥造型中的城市美学以及对人行天桥美学设计的认识,提出从造型与景观角度塑造城市人行天桥的观点.对城市建设有一定的应用价值. 相似文献
27.
Daily rhythms of suburban commuters’ movements in the Tallinn metropolitan area: Case study with mobile positioning data 总被引:2,自引:0,他引:2
Rein Ahas Anto Aasa Siiri Silm Margus Tiru 《Transportation Research Part C: Emerging Technologies》2010,18(1):45-54
The objective of this study is to analyse the diurnal rhythms of city life and its spatial differences in Tallinn, using mobile telephone positioning data. The positioning experiment was carried out in April 2006 over an 8-day period and 15-min intervals, with a random sample of 277 respondents living in new residential areas outside the city of Tallinn.The investigation of the space–time movements and daily distances of respondents showed that the majority of respondents had a similar temporal rhythm related to work, school, services and leisure in the city. Because of the different timing of those activities, the mobile positioning data made it possible to map functional differences in the city. The advantages and disadvantages of mobile positioning data in mapping urban life are discussed in the final section of the study. 相似文献
28.
《运输评论》2012,32(1):5-34
ABSTRACTThis review provides a critical overview of what has been learnt about commuting’s impact on subjective wellbeing (SWB). It is structured around a conceptual model which assumes commuting can affect SWB over three time horizons: (i) during the journey; (ii) immediately after the journey; and (iii) over the longer term. Our assessment of the evidence shows that mood is lower during the commute than other daily activities and stress can be induced by congestion, crowding and unpredictability. People who walk or cycle to work are generally more satisfied with their commute than those who travel by car and especially those who use public transport. Satisfaction decreases with duration of commute, regardless of mode used, and increases when travelling with company. After the journey, evidence shows that the commute experience “spills over” into how people feel and perform at work and home. However, a consistent link between commuting and life satisfaction overall has not been established. The evidence suggests that commuters are generally successful in trading off the drawbacks of longer and more arduous commute journeys against the benefits they bring in relation to overall life satisfaction, but further research is required to understand the decision making involved. The evidence review points to six areas that warrant policy action and research: (i) enhancing the commute experience; (ii) increasing commute satisfaction; (iii) reducing the impacts of long duration commutes; (iv) meeting commuter preferences; (v) recognising flexibility and constraints in commuting routines and (vi) accounting for SWB impacts of commuting in policy making and appraisal. 相似文献
29.
关于带闭链工业机器人的动力学建模研究 总被引:1,自引:0,他引:1
本文在以影响系数矩阵为基础进行带闭链机器人的动力学方程推导时,采用了符号一数值方法。在计算机上获得一,二阶影响系数矩阵和动力学方程中各矩阵元素的最简解近表达式,解决了当分支的广义坐标数不等于6时出现的长方形(奇异)矩阵求逆的解析表达问题。在VAX机上偏制调试出了该方法应的软件,并应用于一个带单闭链地的的孤焊机械手的动力学建模。 相似文献
30.
Y. Q. Sun S. Simson 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2007,45(2):113-132
A nonlinear wagon-track model on curved track has been developed to characterize rail corrugation formation due to self-excitation of the wheel-rail stick-slip process. In this model, wagon movements were described using up to 78 degrees of freedom (DOFs) to model a three-piece freight bogie. Innovatively, the wheelset movements are described using nine DOFs, including torsional and bending modes about the longitudinal and vertical directions. The track modelling is considered as a one-layer structure (two rail beams on discrete spring and damper elements). The wheel sliding after creepage saturation is considered in the wheel-rail interface modelling. Simulation of a case study shows that the frequencies of the wheel stick-slip process are composed of the basic frequency, which might come from the combined effect of sleeper-passing frequency and one-third of the combined torsional and bending frequency of the wheelset, and the double and triple basic frequencies, which form the wavelengths of rail corrugation at different situations. 相似文献