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1.
A well-designed field trip can promote active learning and reinforce classroom materials. Few studies have examined the potential for social media to enhance IS field trip experiences by promoting active and collaborative learning. One major barrier to the exploitation of this potential is the lack of the adoption of social media by students as a learning tool to enhance field trip experiences. Therefore, the first task is to understand how to increase the satisfaction of students in their use of social media to enhance IS field trips. This research sets out to understand the factors that could help increase students’ satisfaction with the use of social media to enhance IS field trips, and thereby their intentions to continue to use social media in future field trips. The results show that to increase user satisfaction, course instructors should ensure that students perceive the social media sites used for enhancing field trip study to be trustworthy, effortless, useful and accepted by their peers. Future research could determine how we can incorporate the use of social media to enhance the field trip learning experience.  相似文献   
2.
A vehicle routing problem solved by using a hybrid genetic algorithm   总被引:1,自引:0,他引:1  
The main purpose of this study is to find out the best solution of the vehicle routing problem simultaneously considering heterogeneous vehicles, double trips, and multiple depots by using a hybrid genetic algorithm. This study suggested a mathematical programming model with a new numerical formula which presents the amount of delivery and sub-tour elimination. This model gives an optimal solution by using OPL-STUDIO(ILOG CPLEX). This study also suggests a hybrid genetic algorithm (HGA) which considers the improvement of generation for an initial solution, three different heuristic processes, and a float mutation rate for escaping from the local solution in order to find the best solution. The suggested HGA is also compared with the results of a general genetic algorithm and existing problems suggested by Eilon and Fisher. We found better solutions rather than the existing genetic algorithms.  相似文献   
3.
In this paper a new VRP variant the Multiple Trip Vehicle Routing Problem with Backhauls (MT-VRPB) is investigated. The classical MT-VRP model is extended by including the backhauling aspect. An ILP formulation of the MT-VRPB is first presented and CPLEX results for small and medium size instances are reported. For large instances of the MT-VRPB a Two-Level VNS algorithm is developed. To gain a continuous balanced intensification and diversification during the search process VNS is embedded with the sequential VND and a multi-layer local search approach. The algorithm is tested on a set of new MT-VRPB data instances which we generated. Interesting computational results are presented. The Two-Level VNS produced excellent results when tested on the special variant of the VRPB.  相似文献   
4.
Risk management is becoming increasingly important for railway companies in order to safeguard their passengers and employees while improving safety and reducing maintenance costs. However, in many circumstances, the application of probabilistic risk analysis tools may not give satisfactory results because the risk data are incomplete or there is a high level of uncertainty involved in the risk data. This article presents the development of a risk management system for railway risk analysis using fuzzy reasoning approach and fuzzy analytical hierarchy decision making process. In the system, fuzzy reasoning approach (FRA) is employed to estimate the risk level of each hazardous event in terms of failure frequency, consequence severity and consequence probability. This allows imprecision or approximate information in the risk analysis process. Fuzzy analytical hierarchy process (fuzzy-AHP) technique is then incorporated into the risk model to use its advantage in determining the relative importance of the risk contributions so that the risk assessment can be progressed from hazardous event level to hazard group level and finally to railway system level. This risk assessment system can evaluate both qualitative and quantitative risk data and information associated with a railway system effectively and efficiently, which will provide railway risk analysts, managers and engineers with a method and tool to improve their safety management of railway systems and set safety standards. A case study on risk assessment of shunting at Hammersmith depot is used to illustrate the application of the proposed risk assessment system.  相似文献   
5.
This study aimed to better understand the impact of business trips on the traveler, the family, and the organization; to learn about maximizing the positive aspects of business travel; and to suggest measures to prevent and manage travel stress. Thirty-five business travelers (American, Israeli, and Swedish) were interviewed about the costs and benefits of their traveling, with a focus on gaining insight into coping strategies. Content analysis of the interviews showed that trips consist of 4 phases--(a) pretrip, (b) journey, (c) stay, and (d) posttrip--and that each phase is characterized by different coping strategies. Business travelers reported using proactive individual and organizational coping strategies in the pretrip phase and a combination of proactive and reactive coping strategies in the other phases. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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A gait experiment was performed to test the effects of obstacle presence on the perception of the risk of tripping. The experimental conditions included lighting condition, obstacle type, color contrast, and obstacle height. Both male and female participants attended this study. The participants reported a perceived risk of tripping (PRT), on a five‐point scale, both before and after a walk. A rating of gait disturbance, also on a five‐point scale, was recorded. The results indicated that lighting condition, obstacle type, color contrast, and obstacle height were all significant on the PRT ratings, both before and after the walk, and on the rating of gait disturbance. The PRTs were positively correlated with the rating of gait disturbance. The possibility of obstacle‐contact, or tripping without falling, in the dimmed condition was 15.5 times of that in the normal lighting condition. A high rating of perceived risk of tripping before a walk was associated with a high gait disturbance score. It, however, did not necessarily lead to the low occurrence of tripping.  相似文献   
8.
近年来,随着中国经济的持续快速增长,发展高速铁路已经成为一种趋势。在我国,已经新建了几条高速铁路,而测量工作在施工过程中起到了决定性的作用。本文基于沪宁城际高速铁路的施工技术,结合沉降观测技术在工程中的应用,分析了沉降观测中内外业应该注意的问题。  相似文献   
9.
本文讨论了土地利用的混合程度与居民出行空间分布的相互作用关系,明确了城市片区的土地利用混合程度概念与计算模式,并通过城市土地利用、居民出行情况的调查数据与统计结果及趋势曲线,分析土地利用混合程度与居民出行空间分布的作用机理,构建片区土地利用混合程度与片区内部居民出行比例两者之间的关系模型。  相似文献   
10.
张晓江 《工程建设与设计》2012,(10):154-156,159
就武汉城际铁路高架站桥梁结构体系、设计方法以及设计过程中存在的问题进行论述,为今后类似工程的设计和施工提供借鉴.  相似文献   
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