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101.
In accordance with Part A, Chapter I, Section I/11 Revalidation of Certificates of the Standards of Training, Certification and Watchkeeping for Seafarers (STCW) 2010 Convention, continued evaluation of professional competence shall be established, among others, by successfully completing an approved training course or courses. Every master, officer and radio operator holding a certificate issued or recognised under any chapter of the convention other than chapter VI, who is serving at sea or intends to return to sea after a period ashore, shall be required, at intervals not exceeding 5 years, to demonstrate continued professional competence, in order to continue to qualify for seagoing service. The main objective of this research is to design a model course using simulation technology to train and demonstrate seafarers’ competence in accordance with the provisions of STCW Code for existing seafarers who need to revalidate their professional maritime certificates also in accordance with the standards governing the use of simulators, Reg I/12 of 2010 STCW Code. The purpose of this revalidation simulation-based model course is to assist maritime training institutes and their teaching staff in organising and introducing specific training courses for revalidation of certificates of competence (CoCs) as well as enhancing, updating or supplementing existing training material where the quality and effectiveness of the training courses may thereby be improved. Only those STCW competences relating to ship bridge simulators will be considered for the model course scenario development and testing.  相似文献   
102.
Users’ perceptions are identified as key elements to understand bicycle use, whose election cannot be explained with usual mobility variables and socio-economic characteristics. A hybrid model is proposed to model the intention of bicycle use; it combines a structural equations model that captures intentions and a choice model. The framework is applied to a case of a university campus in Madrid that is studying a new internal bike system. Results show that four latent variables (convenience, pro-bike, physical determinants and external restrictions) help explaining intention to use bike, representing a number of factors that are linked to individual perceptions.  相似文献   
103.
The kinetic theory for traffic flow equations can be approached using the Grad’s method. This method, which is derived from the kinetic gas theory, was developed for the Paveri-Fontana equation when a special desired velocity model is assumed. A closure relation for the set of macroscopic equations is found when the density, the average velocity and the velocity variance are the relevant variables chosen to describe the system. Simulation results are also shown and a qualitative comparison with other models in the literature is presented.  相似文献   
104.
Abstract

This paper uses the Fertagus renegotiation results as a reference and explores the features that made it such a widely commended case, aiming to identify the best practice to be followed in other cases. The two main questions that this paper aimed to respond were: Was the success of the renegotiation process in the Fertagus contract due to mode-specific factors? Are those factors (mode specific or not) transferable to other modes under public private partnership (PPP) contracts and if so, to what extent? Regarding the mode specificity and transferability analysis, it can be noticed that much of the features were not mode specific in theory, however for the successful transferability to other transport modes, some changes should be made to the PPP model taking into account modal specificities and national contexts.  相似文献   
105.
106.
Decades of research has generated new scientific understanding and technologies aimed at better managing environmental change in estuarine and coastal regions. Yet many across the communities of coastal and estuarine research, management, and funding believe that progress has been too slow in applying this research in practice. This essay reviews how the National Estuarine Research Reserve System’s funding program evolved over the past two decades to improve how researchers and users of research work together to increase the uptake of science to achieve resource management and conservation goals. Incremental innovation in the design of the NERRS funding program enabled more intensive and multiway engagement between funders, researchers, and users, which created new pathways for applying science in practice. Furthermore, these interactions stimulate reflection and adaptation within each separate institutional setting, supporting changes that may science to better support environmental problem solving.  相似文献   
107.

This paper pursues three goals: (1) determining the relative importance of built environment barriers limiting walkability, (2) analyzing the existence of an asymmetry in the way people evaluate positive and negative built environment characteristics, and (3) identifying solutions to tackle the main barriers and quantify their impact in walkability. A best–worst scaling survey was developed to compare the importance of eight different attributes of the built environment regarding walkability. Model results show an asymmetry negative–positive in the judgment and choice of built environment characteristics that promote and impede walkability. The most important barriers, obtained from worst responses, are connectivity, topography, sidewalk surface and absence of policemen. Walkability scores were computed for different neighbourhoods and different policy scenarios were forecasted. Simulation results from the worst responses indicate that improvements in sidewalk quality, along with an increase in the number of police officers, lead to an 85% increase in the walkability score for the lower income neighbourhoods.

  相似文献   
108.

The objective of this paper is the comparison of the efficiency levels for a set of European rail companies in monopoly situations with respect to hypothetical duopoly situations. More specifically, the aim is to test whether the operating costs function of such companies is subadditive. A cost function is subadditive when a single firm can produce all relevant output vectors cheaper than two or more firms. In order to do so the test developed by Evans and Heckman (1984) will be used. It was applied for the American phone company Bell System to assess the convenience of separating the management of local and long-distance services. The results indicate that at least for the companies of a greater size, an efficiency increase (as measured by lower costs), would be obtained from the separation of the current companies in two different companies of a lower size. Besides, these efficiency gains are greater when the two new companies specialize their production, either on passenger or on freight traffic.  相似文献   
109.
Buses are the main transit mode in Brazil, transporting more than 55 million passengers per day. Most of these vehicles run on diesel oil causing a dependence on oil, extensive greenhouse gas emissions and increasing air pollution in urban areas. In order to improve this situation, options for Brazilian cities include the use of alternative fuels and new propulsion technologies, such as hybrid vehicles. This paper proposes a procedure for evaluating the performance of a recently developed hybrid‐drive technology. A simple procedure is presented to compare hybrid‐drive buses with conventional diesel buses in urban operations, particularly with respect to fuel economy. Next the potential for reducing diesel oil consumption through the use of hybrid‐drive buses is assessed. Field tests carried out by the authors indicate that fuel consumption improvement through the use of hybrid‐drive buses would certainly exceed 20%, resulting in lower fuel costs and carbon dioxide (CO2) emissions.  相似文献   
110.
This study investigates how socio-demographic and attitudinal variables of university students affect their desire to increase or decrease their daily commute. The case study is McMaster University in Hamilton, Canada, and data was obtained by means of a web-based survey that included questions regarding travel behavior, socio-demographic information, and attitudes toward travel, land use, and the environment. The objective variable is defined as the ratio of ideal to actual commute time, and regression analysis is implemented to test the relationship between this variable and socio-demographic variables and attitudinal scores. The impact of different attitudes on the gap between ideal and actual commute time is expanded to include three different modes, active travel (walk/cycle), transit, and personal automobile. Interestingly, the results indicate that active travelers tend to be less dissatisfied with their commute, followed by those who travel in a personal vehicle and transit users. A number of attitudinal responses are shown to impact the desire to travel more or less, including variables that relate to the social environment, availability of local activities, quality of facilities, productive use of the commute, and the intrinsic value found in the commute travel. The picture emerges of a traveler who would like to spend more time commuting, as someone who is an active traveler, thinks that getting there is half the fun, dislikes traveling alone, but rather likes to live in an active neighborhood where there is a sense of community. The results suggests that enjoyment of commuting, while a challenge from the perspective of motorized mobility, may provide valuable policy opportunities from the perspective of active transportation.  相似文献   
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