• Journal of the Korean Society for Precision Engineering
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• v.16 no.9
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• pp.117-122
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• 1999

Track rubber parts has heat built-up as long as dynamic loading is applied from running tracked vehicles. Durability is required for rubber part to sustain the heat accumulation and heat exchange between rubber-metal assembly and environmental air and ground. For this research, the track assembly was divided into four parts i.e., bottom track shoe, upper track pad, pin busing and metal structure. Three rubber parts and metal structure were modelled and analyzed with MARC package program to obtain time-temperature data which was induced form mechanical work of tracked vehicles. heat accumulation data was obtained from special experiments under the room temperature of 25$^{\circ}C\;and\;35^{\circ}C$ to simulate the actual environmental conditions. From this research, it is cleared that the environmental temperature does not affect to the heat accumulation speed in rubber parts. Also, the heat built-up mechanism was clarified from the thermo-mechanical work based on numerical analysis and experiments.

• Korean Journal of Construction Engineering and Management
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• v.22 no.6
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• pp.131-137
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• 2021

Since many resources are put into the work of changing the railway operation within limited time, it is important to have a specific work plan and safety management. For this reason, the work schedule is shared in advance, and parallel work is being carried out simultaneously by rail system, such as tracks, trolly wires, and signals. However, due to the nature of the transfer work, the work is carried out at night when the railway operation is finished, and many resources are put into the limited area of the operating line, so the risk of safety accidents and failure to change the operating line is recognized as high. Nevertheless, there is still not enough research done in korea regarding the operation line change construction. Therefore, this study is conducted a survey on the track exchange work of railroad for working people, and analyzed the results of the survey. Finally, a standard work process was suggested to reduce the risk of track exchange work.

• Journal of the Korean Society for Railway
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• v.18 no.6
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• pp.543-551
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• 2015

Quick-hardening track (QHT) is a construction method which is used to change from old ballast track to concrete track. Sufficient time for construction is important, as the construction should be done during operational breaks at night. Most of the time is spent on exchanging the ballast layer. If it is possible to apply the ballast non-exchange type of quick-hardening track, it would be more effective to reduce the construction time and costs. In this paper, pouring materials with high permeability are suggested and a construction method involving a layer separation pouring process considering the void condition is introduced in order to develop ballast non-exchange type of QHT. The separate pouring method can secure the required strength because optimized materials are poured into the upper layer and the lower layer for each void ratio condition. To ensure this process, a rheology analysis was conducted on the design of the pouring materials according to aggregate size, the aggregate distribution, the void ratio, the void size, the tortuosity and the permeability. A polymer series was used as the pouring material of the lower layer to secure the void filling capacity and for adhesion to the fine-grained layer. In addition, magnesium-phosphate ceramic (MPC) was used as the pouring material of the upper layer to secure the void-filling capacity and for adhesion of the coarse-grained layer. As a result of a mechanics test of the materials, satisfactory performance corresponding to existing quick-hardening track was noted.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.30 no.4
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• pp.307-312
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• 2017

In this study, we proposed a method to generate a maintenance documents for railway track through Construction Operations Building information exchange(COBie) which is a subset of Industry Foundation Classes(IFC), a data model for Building Information Modeling(BIM). In order to define the items necessary for railway track maintenance document generation, we analyzed the guideline of maintenance and management to track by the Ministry of Land, Infrastructure and Transport(MLTM), and defined the way to refer to the information items in the COBie spreadsheet. The additional properties not supported in IFC, were created for generation of an Information model that reflecting maintenance information items of railway track by applying user-defined property set within the IFC framework. An IFC-based Information model reflecting the user-defined property was implemented through BIM software, and rail track maintenance information items were transferred to COBie spreadsheet according to the defined approach. It is tested that the information can be transferred from the IFC-based as-built model to the COBie spreadsheet, which can be used to generate the necessary documents for railway facility maintenance work.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2002.04a
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• pp.76-81
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• 2002

The characteristics of the track are important concerning the mobility of tracked vehicles. It can be represented in terms of the track tension and maintaining the track tension adequately guarantees the stable and improved driving of the tracked vehicles. The track tension must be known in order to be controlled and it needs to be estimated in real-time because it is difficult to be measured. The tension around idler and sprocket can be controlled by the frizzy logic control system base on the estimated values. Dynamic Track Tensioning System(DTTS) which is estimating and controlling the track tension. In this paper, simulation tool is developed in order to apply the DTTS to real battle tanks. To construct the simulation tool, the Modeling the tracked vehicle, constructing estimation system, and designing controller should be achieved first and then all subsystem should be organized in one. The simulation tool make the RecurDyn model of tracked vehicle, which is plant model, and the control system exchange their data simultaneously. Simulation with many kinds of driving conditions and road conditions is carried out and the results are interpreted. The interpretation provides necessary information to apply the DTTS to real battle tanks.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.5
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• pp.1954-1962
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• 2012

Recently the increase in the exchange of goods between Europe and Asia caused by social and economic factors creates good opportunities for railways. At the same time, however, it becomes an enormous challenge for railway transport. There are different rail track gauges (i.e narrow/standard/broad gauge) on the continental transportation between Korea (TKR) and Eurasian (TCR/TSR). The existence of various track gauges is one of obstacles preventing the smooth flow of goods by rail. The transferring process system from one track gauge to another could vary with the types of cargo. Service operation of these systems has a decisive effect on working time and cost of storage and transshipment facilities at border crossings. In relation to the above-mentioned factors, it is important to examine the comparison between different methods of transferring goods in different track gauges. In this study, it was performed to evaluate the effectiveness of continental railway transportation systems through analysis scenarios and to suggest technical factors of them.

• Journal of Engineering Education Research
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• v.10 no.4
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• pp.17-28
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• 2007

This paper aims to present the ways to maximize educational effects and facilitate a curriculum renovation through the Specified Track Curriculum Development, a joint lecture system among local universities which is implemented by Busan Educational Alliance of Mechanical Engineering (BEAM) as part of New University for Regional Innovation(NURI), a government-sponsored project to facilitate a balanced regional development of Korea. The Specified Track Curriculum is a unified governing body joined by 4 universities of mechanical engineering departments with an emphasis on their specified academic fields(advanced hightech, environmental, marine and foundational machinery sectors), And the universities mutually recognize academic credits. The track (Specified-Track Curriculum) was carried out three times from winter semester in 2005 to the present and 486 students took the track course for two years. As a result, the track laid out a foundation for the first local joint lecture system in korea with the performance-oriented and students-tailored education, meeting needs of the new era and training efficiency. The graduates' employment rose to 8.5%, compared with that of 2005. According to recent survey conducted on companies employing the graduates, the satisfaction with the graduates' performance marked 9.4% improvement. The track also contributed to expanding human networks, facilitating the educational exchange of local universities.

• Industrial Engineering and Management Systems
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• v.8 no.1
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• pp.29-36
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• 2009

We present two local-search based metaheuristics for the multi-source capacitated facility location problem. In such a problem, each customer's demand can be supplied by one or more facilities. The problem is NP-hard and the number of locations in the optimal solution is unknown. To keep the search process effective, the proposed methods adopt the following features: (1) a multi-exchange neighborhood structure, (2) a tabu list that keeps track of recently visited solutions, and (3) a multi-start to enhance the diversified search paths. The transportation simplex method is applied in an efficient manner to obtain the optimal solutions to neighbors of the current solution under the algorithm framework. Two in-and-out selection rules are also proposed in the algorithms with the purpose of finding promising solutions in a short computational time. Our computational results for some of the benchmark instances, as well as some instances generated using a method in the literature, have demonstrated the effectiveness of this approach.

• 한국방재학회:학술대회논문집
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• 2007.02a
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• pp.159-162
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• 2007

The numerical efforts are presented for investigation of irregular waves passing a slit cassion and a warock block breakwater. In the numerical model, the Reynolds equations are solved by a finite difference method and $k-\varepsilon$ model is employed for the turbulence analysis. To track the free surface displacement, the volume of fluid method(VOF) is employed. Numerical predictions of reflection and transmission coefficients are compared with those of the warock block breakwater with the slit caisson. Energy dissipation and seawater exchange rates of the slit caisson are better than those of the warock block breakwater.

• Proceedings of the KSR Conference
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• 2005.05a
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• pp.314-319
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• 2005

The rubber tire type AGT vehicles had been developed in a few years. And testing are finished on the test track. The extremely differ from heavy train with iron wheels are current collect type and wheel's characteristic. Analysis the current collect gear dynamic with vehicle dynamic and reduce the exchange rate shoes of current collect gear's.