• Transactions of the Korean Society of Mechanical Engineers A
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• v.37 no.11
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• pp.1437-1443
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• 2013

Railways are currently subject to the enforcement of speed limits for each curve as prescribed by the Railway Operating Rules in Korea. However, research is required to determine the maximum speed of trains passing through each curve that allows them to run without the risk of derailment in relation to the speed enhancement of existing railway tracks. In addition, factors affecting the running safety of railway vehicles can be classified into those in terms of vehicle aspects and those in terms of track aspects. This study sought to analyze the running safety of railway vehicles according to changes in the inclination of the rail from among the factors affecting the enhancement of safety against derailment. To increase the speed of trains passing through curves that have high derailment risk, this study also analyzed the running safety of railway vehicles according to the inclination of the rail and changes in running speed while a vehicle passes through each curve section in both the up and the down train line sections between Namsunghyun and Chungdo, which represent the actual conditions of railway tracks.

• Proceedings of the Korean Society of Computer Information Conference
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• 2021.07a
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• pp.211-212
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• 2021

본 논문에서는 스마트 폰의 GPS 센서와 STEP 센서와 카카오 MAP API를 사용한 러닝 보조 애플리케이션을 설계하고 구현한다. 이 애플리케이션은 사용자의 평균속도, 달린 거리, 자주 뛰는 코스 등을 시각화함으로써 사용자가 편리하게 런닝 할 수 있도록 도와주는 기능을 구현한다. 또한 Heart Share 시스템을 이용하여 애플리케이션을 이용하는 사용자들 간의 연대감과 런닝 동기부여를 위한 런닝 보조 및 커뮤니티를 구축한다.

• International Journal of Automotive Technology
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• v.6 no.6
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• pp.615-623
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• 2005

In this research, an effective technique was examined to improve the drift running performance. Concretely, the driver model by which the counter steer was done was assumed to the model by which the vehicle body slip angle (and the vehicle body slip angle velocity) was feed back. Next, the effectiveness of the system which added the assist steer angle corresponding to the steering wheel angle velocity to a front wheel steer angle was clarified as a drift running performance improvement technique of the vehicle. As a result, because the phase advances when the differentiation steer assistance is added, it has been understood to be able to cover the delay of the counter steer when the drift running. Therefore, it has been understood that the drift control does considerably easily. Moreover, it has been understood that the differentiation steer assistance acts effectively at the drift cornering by which the drift angle is maintained in cornering and the severe lane change with a drift at a situation. That is, it was understood to be able to settle to the drift angle of the aim quickly at the time of the drift cornering because the delay of the control steer angle of the counter steer was improved. Moreover, it was understood for the transient overshoot of the vehicle tracks to be able to decrease, and to return to the state of stability quickly at the severe lane change.

• International Journal of Railway
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• v.5 no.2
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• pp.93-101
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• 2012

Owing to the lightening of railway vehicles and increased operation speeds, the reduction of running safety in the presence of crosswind is becoming an important problem. In particular, the running safety tends to decrease when vehicles run on curved track. When a crosswind acts on a vehicle negotiating a curve from the outer side, flange climbing can occur. In this study, a full-vehicle model was constructed using the multi-body simulation software SIMPACK, and a simulation of a bogie vehicle with two-axle trucks negotiating a curve was carried out to examine the running safety under the condition where a crosswind acts on the vehicle from the outer side of the curve. As a result, it was verified that the derailment coefficient of the first wheelset becomes large in the exit transition curve and the coefficient of the third wheelset does in the entrance transition curve, and this trend becomes pronounced at low operation speeds in the presence of a stronger crosswind. It was also shown that the critical derailment coefficients obtained by modified Nadal's formula considering the effect of attack angle become close to the actual derailment coefficients at the timing that flange climbing occurs.

• Korean Journal of Applied Biomechanics
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• v.33 no.1
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• pp.34-44
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• 2023

Objective: The purpose of this study was to examine the effects of increasing running speed on human stability by comparing the Lyapunov Exponent (LyE) and Coefficient of Variation (CV) methods, with the goal of identifying key variables and uncovering new insights. Method: Fourteen adult males (age: 24.7 ± 6.4 yrs, height: 176.9 ± 4.6 cm, weight: 74.7 ± 10.9 kg) participated in this study. Results: In the CV method, significant differences were observed in ankle (flexion-inversion/eversion; p < .05) and hip joint (internal-external rotation; p < .05) movements, while the center of mass (COM) variable in the coronal axis movements showed a significant difference at the p < .001 level. In the LyE method, statistical differences were observed at the p < .05 level in knee (flexion-extension), hip joint (internal-external rotation) movements, and COM across all three directions (sagittal, coronal, and transverse axis). Conclusion: Our results revealed that the stability of the human body is affected at faster running speeds. The movement of the COM and ankle joint were identified as the most critical factors influencing stability. This suggests that LyE, a nonlinear time series analysis, should be actively introduced to better understand human stabilization strategies.

• Journal of Korean Elementary Science Education
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• v.35 no.1
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• pp.65-77
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• 2016

The purpose of this paper was to analyze the kinds and roles of multimedia materials in E-works that are distributed with elementary textbooks (3~6 grade) of the 2009 revised science curriculum. Five criteria (forms, goals, key competencies, inquiry process, running time) were set for this. The sample of the paper was the 784 multimedia materials in E-works of elementary science textbooks (3~6 grade) of the 2009 revised science curriculum. The results of the multimedia materials analysis are as follows: The result of the material forms of multimedia is that the form of highest ratio is text type. But all forms were used evenly in E-work. 56.2% of the multimedia materials are for "inquiry" in the goal criteria, and 65.0% of the multimedia materials are related to "science inquiry" in the key competencies criteria. Two facts indicate many multimedia is used to develop students' inquiry ability. However the ratio of multimedia materials in motivation step is higher than that in inquiry activity step. In analysis of running time, the ratio of "under 5 min" multimedia materials is the highest. But, the ratio of 5~10 min multimedia materials in inquiry part is higher than that in motivation part in The Chi-square test between "running time" and "parts" that consist of motivation part and inquiry part. Through the analysis of module and the categorizing the multimedia materials, we found that the multimedia materials play eleven roles in E-works that are distributed with elementary textbooks.

• Proceedings of the KSRS Conference
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• 2004.10a
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• pp.712-715
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• 2004

War game Simulation System is a simulation system of military operation. In order to ensure all of the data that are running are secure, this system has to emphasize the security policy. In this paper, we analyze the running environment and the weakness of the security about exiting system. For improving the weakness, we design and implement this security system that is consisted of three components: Authentication System, Encryption System and Network Security System. Therefore, we can apply War game Simulation System to security system and improve the secure performance of this one.

• Journal of Engineering Education Research
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• v.17 no.6
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• pp.77-83
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• 2014

This paper deals with the practical experience and lessons to develop the criteria for evaluating projects in Computer Science & Information Engineering. In engineering education, project-based learning is different from problem-based learning. Project tasks are closer to professional reality. And self-direction is stronger in project work. In this paper, the development of project evaluation criteria is introduced with consideration of these differences. It is explained through running examples of basic project courses in Computer Science & Information Engineering.

• Proceedings of the Korean Society of Life Science Conference
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• 2007.10a
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• pp.58.1-58.1
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• 2007

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• Culinary science and hospitality research
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• v.11 no.4 s.27
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• pp.164-177
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• 2005

This study is the present condition of running school based enterprises and tasks in the future, based on the 'regulations for establishment and management of school based enterprises' which came into effect in March, 2004. The investigation showed that 80% of respondents knew about the KIT's school-based enterprise, the bakery. And it seems that the fact that the college is running the bakery does not inspire any special confidence in the products. The students doesn't seem to purchase the products as much as staffs and the professors do, so more active promotions are necessary for student customers. The answer we got to the question 'if you enjoy the our bread and cookies, would you recommend them to your friends or family?' shows that some limit to the 'word of mouth marketing.' And increase in sales of the school based enterprise is closely related to how many times the customers visit the bakery. The school-based enterprise is regarded as one of the most effective alternatives to practice filed based education and innovate teaching methods.