• Journal of the Korean institute of surface engineering
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• v.41 no.6
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• pp.341-350
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• 2008

In friction stir welding for 6061-T6 with various traveling speed and rotation speed conditions, the best mechanical characteristics presented in traveling speed of 507 mm/min and rotation speed of 1100RPM. The maximum tensile strength and yield strength increased with the increasing of traveling speed. The result of the electrochemical characteristic evaluation in friction stir welding at optimum conditions for 6061-T6 Al alloy presented a good characteristics compare to base metal.

• Journal of the Korean Society of Industry Convergence
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• v.12 no.3
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• pp.129-135
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• 2009

This paper describes traveling systems consisting of one major-wheel and three minor-wheels attached to each tip of three spokes. A link of inter-axle plays an important role of the system. It connects secondary axle to the major wheel axle. Its length is determined to ascend stably various stairs. The systems was designed to mount a cart for carrying agricultural products. The systems was applied to ascend stairs, travel on sand and cross a obstacle, despite of simple design.

• Proceedings of the KSR Conference
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• 2009.05a
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• pp.424-432
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• 2009

This paper discusses about the implementation of a simulator for the Navigation Control System(NCS) of bimodal tram. To operate a NCS of bimodal tram, values of all sorts of sensors installed in bimodal tram should be transmitted to the NCS, and the NCS calculates the measured sensor values to determine traveling direction, traveling speed, current position etc. The implementation of the simulator consists of a device applying driver's input transaction function & virtual sensor program and a sub-rack device that controls communication with the NCS to evaluate navigation control function. The virtual sensor program can create routes (map), traveling profiles & seat information et cetera in order to transmit to the NCS, analyzes driver's input values and NCS output values to create virtual sensor values. The sub-rack device takes charge of communication with the NCS using CAN-OPEN, CAN-J1939, MVP protocols. This paper discusses about the implementation of the simulator and afterwards analyzes and evaluates the NCS simulation results.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.49 no.12
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• pp.608-613
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• 2000

This paper describes a fault location technique using wavelets in underground transmission power cable system. Estimation of fault location is performed using data smapled at two ends underground system. In the case of 50% fault of total underground transmission line, fault location is calculated using sampled single-end data in underground transmission line. Traveling wave is utilized in capturing the travel time of the transients along the monitored lines between the relay and the fault point. This traveling time information is provided by the wavelet. Simulation was performed using EMTP, ATP Draw and MATLAB. The results of fault location shown in this paper will be evaluated as an effective suggestion for fault location in real underground transmission line.

• Proceedings of the Korea Inteligent Information System Society Conference
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• 2005.11a
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• pp.369-378
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• 2005

본 논문에서는 유비쿼터스 환경에서 유동 소비자가 서비스의 유동성을 보장받을 수 있는 지능형 여행정보서비스를 제안하고자 한다. 본 시스템은 유비쿼터스 환경에서 여행자가 필요로 하는 정보획득을 돕기 위해 다양한 상품제안, 그 상품들 간의 연계를 통한 맞춤제안을 목적으로 설계되었다 여행정보시스템에 연관된 상품들은 호텔, 비행사, 자동차, 여행지 정보, 음식점 및 Business Trip 등이다. 따라서 여행자의 요구 및 상황의 변화에 맞게 연관상품의 Schedule 맞춤을 위한 지능형 여행 최적정보시스템의 연구가 요구된다. 이를 위해 본 연구에서는 Traveling Service 지원을 위해 첫째 여행자의 요구에 따른 단일상품의 복합상품화(Product bundling)를 위한 방법론을 제안하였다. 둘째, 복합상품을 구성하기 위해 필수적인, 개별정보시스템에 이질적인 형태로 저장되어있는 단일상품에 대한 정보를 공유하기 위해, 여행상품과 온톨로지의 구축이 요구된다. 이에 본 논문에서는 OWL 기반의 온톨로지를 구축하였다. 온톨로지 기반의 여행정보시스템은 향후 시맨틱 웹서비 기반의 지능형 여행정보시스템 구축을 위한 초석으로 활요될 것이다.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.20 no.41
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• pp.177-188
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• 1997

This study describes the important information for establishing Human Computer Interface System for solving the large scale Traveling Saleman Problem in Printed Circuit Board production. Appropriate types and sizes of partitioning of large scale problems are discussed. Optimal tours for the special patterns appeared in PCB's are given. The comparision of optimal solutions of non-Euclidean problems and Euclidean problems shows the possibilities of using human interface in solving the Chebyshev TSP. Algorithm for the large scale problem using described information and coputational result of the practical problem are given.

• Honam Mathematical Journal
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• v.39 no.1
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• pp.27-40
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• 2017

In this paper, we construct exact traveling wave solutions of various kind of partial differential equations arising in mathematical science by the system technique. Further, the $Painlev{\acute{e}}$ test is employed to investigate the integrability of the considered equations. In particular, we describe the behaviors of the obtained solutions under certain constraints.

• Journal of the Korea Society of Computer and Information
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• v.27 no.2
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• pp.1-8
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• 2022

In this paper, we design and implement a GPU-based parallel algorithm to effectively solve the traveling salesman problem through an ant color system. The repetition process of generating hundreds or thousands of tours simultaneously in TSP utilizes GPU's task-level parallelism, and the update process of pheromone trails data actively exploits data parallelism by 32x32 thread blocks. In particular, through simultaneous memory access of multiple threads, the coalesced accesses on continuous memory addresses and concurrent accesses on shared memory are supported. This experiment used 127 to 1002 city data provided by TSPLIB, and compared the performance of sequential and parallel algorithms by using Intel Core i9-9900K CPU and Nvidia Titan RTX system. Performance improvement by GPU parallelization shows speedup of about 10.13 to 11.37 times.

• Journal of Drive and Control
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• v.19 no.4
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• pp.19-28
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• 2022

This paper introduces an automatic steering system for straight traveling capable of being mounted on drivable agricultural machinery which user can handle it such as a tractor, a transplant, etc. The modular automatic steering device proposed in the paper is composed of RTK GNSS, IMU, HMI, hydraulic valve, and wheel sensor. The path generation method of the automatic steering system is obtained from two location information(latitude and longitude on each point) measured by GNSS in advance. From HMI, a straight path(AB line) can be created by connecting latitude and longitude on each point and the device makes the machine able to follow the path. During traveling along the reference path, it acquires the real time position data every sample time(0.1s), compares the reference with them and calculates the lateral deviation. The values of deviation are used to control the steering angle of the machine using hydraulic valve mounted on the axle of front wheel. In this paper, Pure Pursuit algorithm is applied used in autonomous vehicles frequently. For the analysis of traveling characteristics, field tests were executed about these conditions: velocity of 2, 3, 4km/h which is applied to general agricultural work and ground surface of solid(asphalt) and weak condition(soil) such as farmland. In the case of weak ground state, two experiments were executed about no-load(without work) and load(with work such as plowing). The maximum average deviations were presented 2.44cm, 7.32cm, and 11.34cm during traveling on three ground conditions : asphalt, soil without load and with load(plowing).

• Spatial Information Research
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• v.11 no.3
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• pp.275-289
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• 2003

This study focused on offering a helpful information for the touring. To develop a tour route guidance tool, it is needed to use a GIS function, which can suggest a possible shortest path based on time and distance. A Traveling salesman problem algorithm, which was developed to solve multi destination problem in network analysis, was used to implement a tour guidance system. This system was developed using ArcObjects programming components within ArcGIS 8.3. Jeju city was selected for the case study to apply the tool and to test the effectiveness of it. This study demonstrated that this tool was considerably effective for finding a probable optimum tour path in the following aspects. First, it can help tourists to select several attractions from numerous tour sites in an area given limited time. Second, tourist can manage time efficiently by organizing their tour courses on the basis of the tool. Third, tourists can reduce the uncertainties that may happen under unexpected situations in unfamiliar places by obtaining specific spatial information using the tool. Fourth, the Graphic User Interface of the tool can be easily used to obtain visual information of spatial data.