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1.
The introduction of the tonnage tax for shipping companies has been a response to the declining fleets in many European countries. There are strategic and commercial reasons why a maritime presence is desirable, not least of which is to maintain an important skill base. Although regimes have differed they all offer some form of preferential rates of tax for those ships on the register. In certain cases this tax subsidy has been linked to a requirement to train seafarers, notably in the UK. This article analyses the impact of the tonnage tax system and its success in achieving its objectives of fleet expansion and employment with particular reference to the UK.  相似文献   
2.
To identify the potential relationship between Pheaocystis globosa bloom conditions and seawater properties, a hydrobiological survey was performed in the inshore waters of the Eastern English Channel over the course of the phytoplankton spring bloom. Chlorophyll concentration, auto- and hetero/mixotrophic composition of protists and standing stock, and seawater viscosity were measured weekly from March to June 2004. The decline of the bloom is characterized by a massive foam formation in the turbulent surf zone. Before foam formation, seawater viscosity significantly increased, showing a significant positive correlation with chlorophyll concentration. In contrast, after foam formation this correlation was negative, seawater viscosity kept increasing despite a sharp decrease in chlorophyll concentrations. No significant correlation has been found between seawater viscosity and the composition of the phytoplankton assemblages observed during the survey. However, significant positive correlations have been found between seawater viscosity and both the size and the abundance of P. globosa colonies. From the correlation patterns observed between chlorophyll concentration and seawater viscosity, we suggest that the rheological properties of seawater are mainly driven by extracellular materials associated with colony formation and maintenance rather than by cell composition and standing stock.  相似文献   
3.
The focus of this paper is the degree to which day-to-day variability in the individual's travel pattern has a systematic, or nonrandom, component. We first review the different sources of variability in travel, emphasizing the difference between between-individual and within-individual variation and the implications of this difference for travel analysis. After discussing the impact of measurement (i.e. the way in which travel behavior is measured) on the study of repetition and variability, we use the Uppsala data to examine the level of systematic variability in an individual's longitudinal travel record. The analysis focuses on two questions:
  • - How well does observation over one week capture longer-term (five-week) travel behavior; in other words, is behavior highly repetitive from week to week?
  • - How systematic is within-individual variability; in other words, are certain stops distributed over the five-week record in a nonrandom, that is either regular or clustered, fashion?
  • Using measures of travel that include more than one stop attribute (e.g. activity, mode, time of day, and location), we found that:
  • - A seven-day record of travel does not capture most of the separate behaviors exhibited by the individual over a five-week period, but it does capture, for most people, a good sampling of the person's different typical daily travel patterns.
  • - Whereas a considerable portion of intraindividual variability is systematic (nonrandom), clustering is a more important source of nonrandom variation than is regularity.
  • The results suggest that behavior does not follow a weekly cycle closely enough for a one-week travel record to measure the longer-term frequency with which the individual makes certain stops or to assess the level of day-to-day variation present in the individual's record. Because these results are likely to reflect the particular measures of behavior we used, one conclusion of this study is the need for other studies that replicate the aims of this one but use a variety of other travel measures. Only through such additional work can we truly assess the sensitivity of our findings to measurement techniques.  相似文献   
    4.
    The maritime industry underpins international business and world trade. As to be expected, business management is critical for the maritime industry, requiring highly trained individuals and teams to lead the development, implementation and control of sound contemporary management practices. Maritime business degrees are developed by universities to meet such demand by providing graduates with sufficient skills for the onshore business-related roles. This empirical study conducted in Australia, USA and Canada, investigates current and future industry employability skills for maritime business graduates through focus groups, individual interviews and an online survey with senior managers in maritime organisations. This study found the important employability skills for maritime business graduates which include communication, problem solving, adaptability, self-management, team work, and digital literacy and technology. Demand for digital literacy and technology knowledge and skills have increased due to the maritime industry having a trend of moving towards digitalisation and automation. However, the survey findings revealed that a skills focus for maritime business graduates will not be the technology itself but the use and management of technology. In relation to future skills/knowledge required from maritime business degree graduates in 10 years’ time, communication and adaptability are recognised as being the most important. Employers expect that maritime business graduates should be able to adopt new technology and be competent in communication, and be more adaptable given the highly dynamic nature of the maritime industry. Moreover, they require graduates to be equipped with a higher level of computer skills, have a strong work ethic and multilingual skills.  相似文献   
    5.
    Accurate lateral load transfer estimation plays an important role in improving the performance of the active rollover prevention system equipped in commercial vehicles. This estimation depends on the accurate prediction of roll angles for both the sprung and the unsprung subsystems. This paper proposes a novel computational method for roll-angle estimation in commercial vehicles employing sensors which are already used in a vehicle dynamic control system without additional expensive measurement units. The estimation strategy integrates two blocks. The first block contains a sliding-mode observer which is responsible for calculating the lateral tyre forces, while in the second block, the Kalman filter estimates the roll angles of the sprung mass and those of axles in the truck. The validation is conducted through MATLAB/TruckSim co-simulation. Based on the comparison between the estimated results and the simulation results from TruckSim, it can be concluded that the proposed estimation method has a promising tracking performance with low computational cost and high convergence speed. This approach enables a low-cost solution for the rollover prevention in commercial vehicles.  相似文献   
    6.
    This study investigates the relationship between surface street traffic volume and single-family house prices in a relatively small city in the US. Hedonic price models are estimated using data from 9670 transactions that occurred between January 1998 and March 2011. It is discovered that parcels fronting or adjacent to a high-traffic street sell, on average, at an 8.1% discount compared to similar parcels that are not so situated. Restricting the analysis to parcels on or adjacent to a high-traffic street, house price and traffic volume are found to be negatively related; a doubling of volume from any particular traffic count, ceteris paribus, reduces selling price by an average of 2.1%.  相似文献   
    7.
    8.
    This paper, in two parts, reports on the Seaport Development in the European Communities Research Project wherein forty interviews with decision-makers were held in European seaports, and another forty were held with shipowning organizations. This part of the paper reports on analysis of the open-ended tape-recorded responses of the interviewees to six separate sets of propositions they were shown. The first major conclusion is that decision-makers in the ports and shipping industries have a great deal to offer in helping to shape future EC policies about seaports. The second is that these decision-makers on the whole agree with students of the subject, but outside the industries, that a step-by-step approach is possible towards a Common Seaports Policy. Indeed, without prompting, some respondents even confirmed a previously published suggestion for the first stage of this process—the necessity for an agreed standard basis for ports' accounts. It is believed that a small secretariat within the Brussels Commission could weld representatives of the industries into a working group which could make real progress by consulting their colleagues through interviews similar to those successfully conducted for this project.  相似文献   
    9.
    10.
    The Passenger Vessel Services Act (PVSA) of 1886, a cabotage law, attempts to shield U.S. maritime shipping from foreign competition. It also applies to the U.S. cruise ship industry. The PVSA requires foreign cruise ships that carry passengers between U.S. ports to also stop at foreign ports. Norwegian Cruise Line America (NCLA), which operates one U.S. flagged cruise ship in Hawaii, wants the U.S. Customs and Border Protection to require foreign cruise ships offering Hawaii itineraries from the U.S. west coast to spend more time in foreign ports. We analyze the merits of NCLA's proposal. We argue that rather than making the PVSA even more protectionist, the law should be repealed.  相似文献   
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