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991.
This study asses the effectiveness of classroom-based bridge resource management (BRM) training for junior naval officers, in which general principles of human behaviour and performance in teams and under stress were conveyed. Although BRM training is recommended by the International Maritime Organization and is increasingly common in seafaring, very little is known about whether the adaptation of crew resource management (CRM) training from aviation to the maritime domain has been successful and what type of training is effective. A study with a quasi-experimental, two-factorial mixed design was conducted with BRM training as the between factor and time as the within factor. For 117 study participants, evaluation criteria were assessed on all levels as defined by Kirkpatrick (Train Dev J, 178–192 1979): subjective training evaluation, knowledge, attitudes and behaviour as well as performance while commanding a vessel during a real-world exercise. BRM participants showed better subjective training evaluations and more BRM-related knowledge than controls. Training did not produce differences between groups regarding BRM-related attitudes, the demonstration of non-technical skills or the overall success in the real-world exercise. Overall, BRM training effectiveness was rather low, which can most probably be attributed to the focus of training on generalizable knowledge, skills and attitudes at the expense of their specific application to the context of the real-world exercise. In the design of BRM and CRM training courses alike, the effective application of general principles to a given context must be defined, and the application must be emphasised during training delivery.  相似文献   
992.
With the Standards of Training, Certification and Watchkeeping Convention 1995 (STCW’95) moving seafarer training towards outcome-based education (OBE), emphasis has shifted to assessment practices that will allow seafarer students to demonstrate their ability to perform workplace tasks at standards described in the STCW Code. This paper argues that authentic assessment comprising of performance-based tasks applied in real-world and meaningful contexts can provide a holistic approach to competence assessment for seafarers. But, authentic assessment can capture essential aspects of workplace tasks and result in consistency of student performance in different contexts only if they are valid and reliable. Rubrics as assessment tools are known to increase validity and reliability of assessments; however, it can do so only if different aspects of its own validity and reliability have been addressed. A literature review undertaken for this paper has uncovered an absence of academic investigation and empirical study on the different aspects of validity and reliability of authentic assessment through assessment rubrics. Moreover, there exists an even greater absence of global research on authentic assessment in the area of seafarer training. Through an investigation of authentic assessment, this research has uncovered the importance of using valid and reliable rubrics in order to improve not only the assessment process but also the tools and methods used to support the valid, reliable, and authentic assessment of outcomes achieved in the learning process. Future research aims to offer insights into improving the validity and reliability of rubrics and to empirically investigate how they can be used in authentic assessment within the confines of the STCW Code, in particular, to improve seafarer training practices, student engagement, resulting learning outcomes, and employer and regulator satisfaction with the attainment of the standards stipulated in the STCW Code to produce an evidence of competence.  相似文献   
993.
This study investigated whether the availability of transportation alternatives for older drivers is a determinant of the decision to cease driving. We recruited participants from a total of 7827 drivers aged 69 years or older living in Ibaraki Prefecture, Japan who were scheduled to renew their driving license between February and April 2011. In November 2010, we distributed questionnaires to collect data on predictors of driving cessation, and again in December 2012 to determine who had actually ceased driving. The relative impacts of factors related to driving cessation were then estimated. Of the 3089 respondents, 157 did not renew their license. The strongest determinants of this decision were having been advised to stop driving and if they had developed less confidence in their ability to drive safely. Even so, respondents were far more likely to have actually stopped driving if they were sure that someone else was available to provide a ride when they needed one. The final decision to stop driving is strongly influenced by personal convenience based on private transport, especially amongst drivers who have been advised to stop. The availability of public transport alternatives is not as important a factor in this decision.  相似文献   
994.
Transportation infrastructure planning process requires cost–benefit analysis in the evaluation of project proposals. Value of time (VOT) facilitates the conversion of travel time savings, which is a significant proportion of benefits in monetary terms. In cases where VOT has not been established, planners resort to crude estimates that often results in erroneous or biased measurements of benefits. This is the case of the Western Visayas region in the Philippines where transportation studies are rare. Secondary cities and its peripheral regions have often been overlooked subjects of transportation studies. In this study, multinomial logit models using revealed preference data were estimated to facilitate the calculation of the VOT. The total cost, square of the total cost, and total time were identified as significant explanatory variables affecting mode choice. The square of the total cost term was introduced in the models in order to account for income effect. Results indicate that VOT estimates for the inter-island passenger transportation between Iloilo and Negros Occidental generally range from 78.15PHP to 179.15PHP (1.91USD to 4.37USD) depending on trip and traveller characteristics.  相似文献   
995.
Using multi-day, multi-period travel diaries data of 56 days (four waves of two-week diaries) for 67 individuals in Stockholm, this study aims to examine the effects of out-of-home and in-home constraints (e.g. teleworking, studying at home, doing the laundry, cleaning and taking care of other household member[s]) on individuals’ day-to-day leisure activity participation decisions in four different seasons. This study also aims to explore the effects of various types of working schedules (fixed, shift, partial- and full-flexible) on individuals’ decisions to participate in day-to-day leisure activities. A pooled model (56 days) and wave-specific models (14 days in each wave) are estimated by using dynamic ordered Probit models. The effects of various types of working schedules are estimated by using 28 days of two waves’ data. The results show that an individual’s leisure activity participation decision is significantly influenced by out-of-home work durations but not influenced by in-home constraints, regardless of any seasons. Individuals with shift working hours engage less in day-to-day leisure activities than other workers’ types in both spring and summer seasons. The thermal indicator significantly affects individuals’ leisure activity participation decisions during the autumn season. Individuals exhibit routine behaviour characterized by repeated decisions in participating in day-to-day leisure activities that can last up to 14 days, regardless of any seasons.  相似文献   
996.
Activity conflict resolution as the core of scheduling process in activity-based modeling is a challenging step because the activity diary databases mostly report the outcome of the scheduling decisions and often fail to capture key factors influencing the resolution process itself. Consequently, most activity-based frameworks ignore modeling this process by using either predefined set of activity patterns or priority-based assumptions to schedule daily activities and prevent conflict occasions. ADAPTS is one of the few activity-based models that attempts to simulate the process of activity scheduling and resolve the conflicts as they occur. This paper advances the current rule-based conflict resolution model of ADAPTS by implementing an advanced and flexible non-linear optimization model. A set of linear optimization sub-models is then proposed that together perform the same task as the non-linear model, however they are much easier to implement and maintain, while fast to run and flexible to extend. The proposed approach defines an objective function, which aims to minimize the extent of changes in timing and duration of conflicting activities, while fitting them in the schedule. Comparing performance of the proposed model with TASHA scheduler and former resolution module of ADAPTS using CHASE scheduling process data reveals significant improvement in fitting the newly planned activities in the schedules with the minimal modifications in the timing and duration of activities.  相似文献   
997.
Existing user equilibrium models of activity-travel scheduling generally fall short in representing travelers’ decision-making processes. The majority have either implicitly or explicitly assumed that travelers follow the principle of utility maximization. This assumption ignores the fact that individuals may be loss–averse when making activity-travel decisions. Allowing for the situation that travelers possess accurate information of the urban-transportation system due to modern technologies, studies on reference-dependent decision-making under near-perfect information are receiving increasing attention. In view of traveler heterogeneity, individuals can be divided into multiple classes according to their reference points. In this paper, we propose a reference-dependent multi-class user equilibrium model for activity-travel scheduling, which can be reformulated as a variational inequality problem. Moreover, comparative analyses are conducted on the equilibrium states between utility-maximization (no reference) and reference-dependency of exogenous and endogenous references. A numerical example regarding combined departure-time and mode choice for commuting is conducted to illustrate the proposed model. The simulated results indicate that reference points and loss aversion attitudes have significant effects on the choice of departure time and mode.  相似文献   
998.
A fully three-dimensional model was used to investigate the optimal value for intake valve lift in a CAI engine. Uniform mixing in the engine is a key parameter that affects the auto-ignition reliability and thermal efficiency. The method of intake of the air supply often determines the uniformity (or quality) of the fuel-air mixture. In this paper, four strategies were applied for controlling the swirl intensity of intake air. The variation of the intake valve lift induces different swirling and tumbling intensities. Both experimental data and 1D WAVE software (Ricardo, Co.) were coupled with the 3D model to provide pressure and temperature boundary conditions. The initial condition of the EGR mass fraction was also provided by the 1D model. The benchmark scenario (Case 1) was considered as a valve lift with 2 mm for all intake valves. We found that an intake valve lift of 6 mm with the other intake valve closed (i.e., Case 5) yielded the largest swirling (helical motion in the axial direction) and tumbling, which in turn rendered optimal fuel-gas mixing. We also found that fuel distribution affected the auto-ignition sites (or spot). The better the mixing, the greater the gas temperature and combustion efficiency achieved, as seen in Case 5. The NOx level, however, was increased due to the gas temperature. The optimal operating condition is selected from the viewpoints of environmental protection and combustion efficiency.  相似文献   
999.
In order to develop a fatigue design method for actual railroad car and commercial vehicle body structures using the fatigue data of simulated single spot-welded lap joints, we first analyzed the stress distribution and evaluated fatigue strength of spot-welded T-type members that are the components of actual railroad car and commercial vehicle body structures. Next, fatigue design approach of these members using the fatigue data of single spot-welded lap joints was investigated. From our results, we found that, even though there was a quantitative difference of fatigue strength between the single spot-welded joint and the actual members over the same number of fatigue cycles, through the use of appropriate correction, the fatigue design criterion of actual spot-welded members, such as those used in railroad car and commercial vehicle body, can be predicted using the fatigue strength of single spot-welded joint.  相似文献   
1000.
In order to safely maintain a vehicle, it is necessary to verify the most important systems that affect safety during Periodic Motor Vehicle Inspections (PMVIs). In a previous paper, a test method and validation criteria were suggested by the authors to verify shock absorber status during PMVIs, as they are a fundamental component that may wear out during a vehicle’s life. In this paper, variations of the performance of the vehicle’s brakes resulting from shock absorber wearing have been analyzed, in order to confirm whether the suggested criteria is valid for taking into account longitudinal forces and pitch movement on the vehicle. A simulation-based study was conducted with several configurations of a worn damper on a vehicle driving on two virtual roads: smooth and undulating. The results confirmed that the damping coefficient established as an acceptable value to verify the shock absorber status in PMVIs is also valid considering the forces involved in a braking maneuver.  相似文献   
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