• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 2004년도 추계학술대회 논문집
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• pp.219-224
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• 2004

There have been many researches on machine tool vibration and chatter to obtain assessment procedure and more productivity. In this paper chatter limit is predicted on a universal machining center which used a parallel mechanism. The prediction method uses the combination of structural dynamic characteristics and cutting dynamics. So the dynamic characieristics were obtained by vibration experiments. We showed the unstable cutting conditions, and from them we could plot the unstable borderlines.

• 소음진동
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• 제10권4호
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• pp.686-691
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• 2000

In this paper a computer aided analysis method is proposed for durability assessment in the early design stages using dynamic analysis, stress analysis and fatigue life prediction method. From dynamic analysis of a vehicle suspension system, dynamic load time histories of a suspension component are calculated. From the dynamic load time histories and the stress of the suspension component, a dynamic stress time history at the critical location is produced using the superposition principle. Using linear damage law and cycle counting method, fatigue life cycle is calculated. The predicted fatigue life cycle is verified by experimental durability tests.

• 영재교육연구
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• 제22권3호
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• pp.703-728
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• 2012

이 연구의 목적은 초등 과학 영재를 교수 및 평가하는 데 있어 종래의 정적 방법이 아닌 역동적 방법을 채택하여 전기회로 개념 이해 과정을 분석해 보는 것이다. 초등 과학 영재 11명을 대상으로 과학적인 전기회로 개념으로의 이해를 의도한 역동적 과학 평가를 실시하여 스캐폴딩 양상을 중심으로 변화 과정을 알아보고, 영재학생의 개념 변화 과정에서 나타나는 특징을 분석하였다. 연구 결과 첫째, 역동적 과학 평가를 통해 초등 과학영재의 개념 이해에 유용한 스캐폴딩 투입 특성을 확인하였다. 둘째, 역동적 과학 평가 전략에 의한 개념 정립이 개별 학생의 특성에 따라 다양한 방식으로 나타났다. 셋째, 전기회로 개념 이해의 각 장면에서 효과적으로 작용했던 전략을 확인할 수 있었다.

• 산업경영시스템학회지
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• 제24권65호
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• pp.51-63
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• 2001

The present experiment investigated the possibility of evaluating of the human sensibility contingent on the speed and modes of driving using the responses from the autonomic nervous system, subjective assessments, Simulator Sickness (55) in dynamic simulator. The three conditions of the speed of driving were 40 $\pm$ 10 km/h, 100$\pm$10 km/h, 160 $\pm$ 10 km/h, and the participant was instructed to drive the car for three minutes on the elliptical track. It is programed in such a way that the modes of driving can be changed smoothly using road DB in Dynamic Simulator, and for signifying the change of the condition the road signs were used. The instruction was given to the participant to drive the car on the fixed speed of 20 km/h for 30 seconds, then to drive the car on sudden-start mode of driving from the 20 km/h to 160 km/h within 10 seconds. For the sudden-stop mode of driving, it was instructed that stop the car from the speed of 160km/h to 20km/h within 10 seconds when the subject see the road sign, then drive the car at the fixed speed of 20 km/h for 30 seconds. The results of the subjcetive assessment showed that the level of pleasantness and the tension was increased, and physiological response showed that the level of activity of the autonomic responses were also increased as the speed of the car increased. Also, for results on the driving modes showed that the level of pleasantness was highest for the sudden-stop, next highest was sudden-start, and the lowest was 20 km/h fixed speed condition for the subjective assessment, and tile order of the level of activation of the autonomic nervous system showed the same results as above. From the results of the present study it was concluded that the presentation and evaluation of the stimulus for the human sensitivity is possible in dynamic simulator.

• 전산구조공학
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• 제27권2호
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• pp.26-34
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• 2014

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 1998년도 추계학술발표회요약집
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• pp.179-179
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• 1998

• 전산구조공학
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• 제35권1호
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• pp.25-34
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• 2022

• 한국심리학회지:법
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• 제13권2호
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• pp.99-119
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• 2022

성범죄자의 재범 우려가 큰 가운데 특정 성범죄자들은 다른 성범죄자들에 비해 재범하는 경향이 더 높은 것으로 알려져 있다. 이에, 연구자들은 성범죄자의 재범을 예측하는 요인들을 규명하기 위해 노력해왔다. 본 연구에서는 현재 교정시설에서 사용하는 STATIC-99(정적 위험 요인 평가)와 HAGSOR-동적요인을 사용하여, 각 도구의 재범 예측력을 분석하였다. 분석 결과 STATIC-99와 HAGSOR-동적요인은 통계적으로 유의한 재범 예측력을 가진 것으로 나타났다(각각 AUC = .737, AUC = .597, ps < .001). 그러나 성범죄 재범에 대해서는 STATIC-99만 통계적으로 유의한 예측력을 보였다(AUC = .743, p < .001). 또한 HAGSOR-동적요인을 추가한 Model의 재범 예측에 대한 설명력은 STATIC-99만을 투입한 Model보다 통계적으로 유의한 수준에서 증가하는 것으로 나타나(∆χ² = 12.721, p < .001), HAGSOR-동적요인의 증분적 재범 예측력이 확인되었다. 그러나 성범죄에 대한 증분적 재범 예측력은 확인되지 못하였다. 재범 위험성 평가 항목 중 정적 위험요인은 친족피해자를 제외한 모든 항목이 재범을 유의하게 예측하였으며, 동적 위험요인 중 범죄적 성격, 대인관계 공격성, 사회적지지(부족)이 재범에 영향을 미치는 것으로 분석되었다. 결과에 대한 함의와 현장에서 도구의 사용 문제, 개선 방향 등이 추가로 논의되었다.

• Computers and Concrete
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• 제18권6호
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• pp.1195-1211
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• 2016

In this study, seismic behaviour of reinforced concrete buildings using the pushover and incremental dynamic analysis method was investigated. A numerical study was performed for a reinforced concrete frame building. Pushover analysis according to uniform and triangular load shapes and incremental dynamic analyses were performed for selected building. For the nonlinear analysis, three ground motion records were selected to ensure compatibility with the design spectrum defined in the Turkish Seismic Code. The maximum response, dynamic pushover curve, capacity curves, interstorey drifts and moment rotation curves for various element ends of the selected building were obtained. Results were compared each other and good correlation was obtained between the dynamic analyses envelope with static pushover curves for the building.

• Wind and Structures
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• 제20권2호
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• pp.143-168
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• 2015

A numerical model for analyzing air-train-track interaction is proposed to investigate the dynamic behavior of a high-speed train running on a track in crosswinds. The model is composed of a train-track interaction model and a train-air interaction model. The train-track interaction model is built on the basis of the vehicle-track coupled dynamics theory. The train-air interaction model is developed based on the train aerodynamics, in which the Arbitrary Lagrangian-Eulerian (ALE) method is employed to deal with the dynamic boundary between the train and the air. Based on the air-train-track model, characteristics of flow structure around a high-speed train are described and the dynamic behavior of the high-speed train running on track in crosswinds is investigated. Results show that the dynamic indices of the head car are larger than those of other cars in crosswinds. From the viewpoint of dynamic safety evaluation, the running safety of the train in crosswinds is basically controlled by the head car. Compared with the generally used assessment indices of running safety such as the derailment coefficient and the wheel-load reduction ratio, the overturning coefficient will overestimate the running safety of a train on a track under crosswind condition. It is suggested to use the wheel-load reduction ratio and the lateral wheel-rail force as the dominant safety assessment indices when high-speed trains run in crosswinds.