• International Journal of Railway
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• 제2권2호
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• pp.70-79
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• 2009

An optimal driving strategy of a train in a long journey on a nonsteep track has four phases: an initial power phase, a long hold speed phase, a coast phase and a final brake phase. The majority of the journey is speed holding. On a track with steep gradients, it becomes necessary to vary the strategy around steep sections of track because it is not possible to hold a constant steep on steep track. Instead we must interrupt the speed hold phase with a power phase. The aim of this paper is to show that there is a unique power phase that satisfies the necessary conditions for an optimal journey. The problem is developed and solved for various cases, from a simple single steep gradient to a complicated multiple steep gradient section. For each case, we construct a set of new conditions for optimality of the power phase that minimises the energy used during the power phase subject to a weighted time penalty. We then use the new necessary conditions to develop a calculate scheme for finding an optimal power phase for a steep incline. We also present an example to confirm the uniqueness of an optimal power phase.

• 대한치과의사협회지
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• 제16권2호통권105호
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• pp.147-150
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• 1978

The author conducted an experiment on the relativity between the mandibular buccal and lingual cusp inclines by means of measuring full arch plaster cast teeth of the fifty student subjects of the College of Dentistry, Seoul National University. The results were as follows: 1. The statistical relativity between the mandibular buccal and lingual cusp inclines in individual tooth was hardly recognized. 2. In the cusp incline data of the whole posterior teeth, the rough basis for the harmonizing with the other occlusion factors was recognizable. 3. The cusp inclination itself was incomplete in mechanical balance, therefore, it might be said that there were a lot of possibilities that the cusp incline may act as a potential etiological factor to give rise to occlusal diseases.

• 한국전문물리치료학회지
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• 제15권4호
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• pp.10-17
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• 2008

The purpose of this study was to determine the therapeutic effect of slope changes of the treadmill with body weight-supported training on gait characteristics in patients with hemiplegia. The volunteered subjects were divided into 3 groups based upon slope changes: control group ($0^{\circ}$ incline), $7^{\circ}$ group ($7^{\circ}$ incline), $12^{\circ}$ group ($12^{\circ}$ incline), They were trained the body weight-supported treadmill training (BWSTT) for 8 weeks. All subjects were supported up to 40% of their body weight on the treadmill training and the support was gradually decreased to 0~10% as the subjects were adapted to the training. There were significant improvements of walking velocity, step length of the affected side, the asymmetry ratio of step length in $7^{\circ}$ group (57.80 cm/s, 67.25 cm, .14), $12^{\circ}$ group (71.00 cm/s, 71.00 cm, .11) than control group (40.62 cm/s, 55.00 cm, .74) (p<.05): there were no differences between $7^{\circ}$ group and $12^{\circ}$ group in the all outcomes (p>.05). Both $7^{\circ}$ group and $12^{\circ}$ group scored higher than the control group in those outcomes and finally the effects of slopes changes of the treadmill were effective on gait characteristics of patients. But it s till remains undetermined what degree on the treadmill might be better to train the hemipareric patients. Therefore, more studies are required to look into minutely the changes of slopes of the treadmill influencing on gait characteristics.

• 한국의류학회지
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• 제38권4호
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• pp.455-466
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• 2014

This study examines the effectiveness of CSR through the expectancy disconfirmation theory. The change of CSR belief after a corporate social irresponsibility (CSIR) crisis was investigated in terms of activity timing (proactive activities before CSIR crisis/reactive activities after CSIR crisis). Study 1 explores the influence of CSR belief perceptions formed through usual CSR activities on CSR belief decline after a CSIR crisis and the moderating effect of CSR activity types. Higher CSR belief perceptions are formed through usual CSR activities that result in a large CSR belief decline. The moderating effect of CSR activity types on CSR belief decline is found. Volunteer activity has the strongest depending effect on CSIR crisis. Study 2 explores the influence of CSR belief perceptions formed through CSIR crisis on a CSR belief incline after CSR activities and the moderating effect of CSR activity types. The lower CSR belief perception after CSIR crisis results in a high CSR belief incline after CSR activities. The moderating effect of CSR activity types on CSR belief incline is found. Cause-related marketing has the strongest overcoming effect on a CSIR crisis.

• 한국방사선학회논문지
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• 제9권7호
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• pp.473-478
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• 2015

사회 인구학적 특성을 보정 하였을 때 대사 증후군의 예측에 가장 높은 연관이 남녀 모두에서 비만-복부 비만군이라고 보고되고 있으며, 의료기기의 발전과 더불어 방사선에 대한 피폭선량이 증가하고 있는 추세이다. 이에 흉부 X선 검사에서 복부의 비만정도를 가정하여 흉부팬텀에서 앞쪽방향(forward)으로 각도를 부여한 후 기준영상과 비교하여 입사표면선량과 영상의 왜곡 정도를 평가하였다. 흉부팬텀의 각도가 앞쪽방향으로 $5^{\circ}$ 증가할 때 마다 폐의 가로직경은 1.22%, 세로직경은 0.44% 증가하였다. 심장직경은 앞쪽방향으로 $5^{\circ}$ 증가할 때 마다 1.01% 증가, CTR은 0.27% 감소가 관찰되었다. 그 중 폐의 가로직경이 가장 큰 증가, 폐의 세로직경이 가장 작은 증가를 보였고 CTR은 작은 감소를 보였다. 그러나 팬텀에 입사하는 표면선량 측정의 경우, 흉부팬텀의 각도가 앞쪽방향으로 $5^{\circ}$ 증가할 때 마다 6.12%의 비교적 큰 증가를 보였다. 임상에서 흉부 X-선 후전방향촬영을 시행하는 경우, 복부비만 등으로 인해 흉부의 각도가 기울어짐에 따라 영상의 왜곡뿐만 아니라 환자에게 노출되는 선량이 증가되고 재촬영으로 추가적인 방사선 피폭이 발생될 수 있으므로 올바른 위치잡이에 주의를 기울여 환자의 방사선피폭 감소에 노력을 해야 할 것이다.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2005년도 학술발표회(2)
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• pp.1114-1115
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• 2005

• 대한치과보철학회지
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• 제8권1호
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• pp.30-36
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• 1968

The measurements on the various items, such as arch form, kinds of anterior dental arch, degree of curvature in anterior dental arches, relationship between direction of the disto-incisal edge of the canine and first premolar, and kinds of posterior dental arch in upper dental arches were studied on 311 cases of the Korean adults aged from 20 to 30years. The results were as follows. 1. The commonest type of the upper dental arches was U-type (53.7%), the remaining were O-type (25.4%) and V-type (20.0%). 2. A slight curvature type (71.87%) prevailed against angulated curvature type in upper anterior dental arches. 3. The degree of curvature from $121^{\circ}$ to $160^{\circ}$ in anterior dental arches was common, and the degree of curve of 1-type with on curvature was smaller than 4, 5 type with two curvature. 4. The direction of the disto-incisal edge of canine went between the tip of the buccal cusp and the lingual incline of the buccal cusp of the first premolar in most dental arches and went lingual incline of the buccal cusp of the first premolar in U-type, from buccal cusp to lingual cusp of the first premolar in O-type and were distributed from buccal edge to central groove of the first premolar in V-type. 5. A posterior dental arch with almost straight curvature was common in 60.87%, and 4-type with a half rounded curve from first premolar to second molar was next.

• 정보처리학회논문지B
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• 제16B권4호
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• pp.257-262
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• 2009

본 논문에서는 실제 도로환경의 속도 표지판 영역 추출 및 인식 방법을 제안한다. 화소의 색상정보를 이용하여 속도 표지판 영역을 추출하고 추출된 속도 표지판 영역 안에서 숫자 영역만 다시 추출한다. 표지판의 경사여부를 판단하여 시계방향, 반시계방향으로 각각 표지판을 회전시켜 기울기를 보정한 후 인식을 행함으로써 인식률을 제고한다. 도로환경의 동영상을 대상으로 인식을 행한 결과 일반적인 속도표지판 뿐 아니라 기울어진 환경에서도 매우 강건한 인식 결과를 보인다.

• 대한치과교정학회지
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• 제23권4호
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• pp.607-618
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• 1993

If the centric prematurity occurs after orthodontic treatment, it creates centric slide regarded as a possible factor in the cause of temporomandibular disorder and/or postorthodontic relapse. The purpose of this study was to investigate the manner of centric prematurity and centric slide in postorthodantic patients. The 36 orthodontic patients who had been treated with edgewise appliance at least 3 mouths previously were used in this study. After recording centric relation by the leaf gauge technique, the centric prematurity and centric slide were studied using SAM2 articulator and mandibular position indicator. The results were as follows : 1. The highest percentage of centric prematurities were found on the second molars. 2. The buccal incline of the palatal cusp was the most frequent area of centric prematurities in the maxilla, while the lingual incline of the buccal cusp was the most frequent area in the mandible. 3. There were no trends in the direction of centric slide on the mandibular position indicator. 4. There were no significant differences in centric discrepancies between the premolar extraction and nonextraction group.

• 설비공학논문집
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• 제17권5호
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• pp.452-458
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• 2005

In Korea, pumping pipe using gravity way by water is most popular method in drainage system. But, it is difficult to repair a drainpipe in this method because the drain pipe diameter is increased as using this method. In this research, we propose a new drainage system. The system aim for an adaptedness with buildings, freedom of plan, construction and renewal in water pipe equipments, etc. The new system is not need of incline of piping, and it uses drainage power that is changed potential energy by high velocity flow as making Siphonage at vertical pipe. Therefore, the diameter of piping can decreased than existing piping system established in the ceiling. Also because connecting position will be located at the lower part, it is changed the potential energy of drainage to the high velocity flow. In addition, drainage will be smooth because the fixture drain is linked by each drain pipes.