• Geomechanics and Engineering
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• 제8권2호
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• pp.221-235
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• 2015

A series of laboratory model tests were conducted to investigate the effects of buried pipes location on the bearing capacity of strip footing in cohesionless soil. The variables examined in the testing program include relative density of the sand, loading rate of tests, burial depths of pipe and horizontal distance of pipe to footing. The test results showed a significant increase in bearing capacities when embedment ratio of pipe and horizontal distance of pipe to footing were increased. Based on the test results, it can be concluded that the location of pipes and relative density of sand are main parameters that affect the bearing capacity of strip footing. However, loading rate has not considerable effect on bearing capacity.

• 한국대기환경학회지
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• 제2권1호
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• pp.23-31
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• 1986

Meteorological Measurement was performed for evaluation of the horizontal vertical standard deviation $(\sigma_y, \sigma_z)$, surface roughness length and stmospheric stability during the period of March to October 1985 The major results are as follows; 1) The average value of surface roughness length was 144cm at NEPI. 2) In frequency distribution of atmospheric stability, neutral state (D class) was dominent in Seoul (29%) and Pusan (30%). Unstable states (A. B. C. class) were 26% in Seoul and 24% in Pusan. Also, stable states (D. E. F class) were 74% in Seoul and 76% in Pusan. 3) Standard deviations of horizontal ad vertical direction were evaluated as a function of downwind distance and atmospheric stability at NEPI, Jamsil and Pujeondong (Pusan). Standard deviation of horizontal direction was largest at NEPI among 3 areas because of mechanical turbulence resulting from difference of surface roughness length.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2001년도 봄 학술발표회 논문집
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• pp.551-558
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• 2001

The horizontal drain method is one of methods improving reclamation ground. This method reduces consolidation time by using drained installed horizontally, and negative pressure is applied on end of these drains by vacuum pump. But, effective negative pressure still wasn't evaluated in applying this method to reclamation ground. To estimate optimum negative pressure, soil box test that make a model the in-situ by installing horizontal drains in the center is performed pressing different vacuum pressure In the laboratory, and the variations in settlement and volume of drained water through the drains during consolidation process were measured. Also, water content with distance from drain and with depth is measured after the test.

• 한국광학회:학술대회논문집
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• 한국광학회 2006년도 하계학술발표회 논문집
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• pp.467-468
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• 2006

• 한국운동역학회지
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• 제15권4호
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• pp.97-104
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• 2005

Previous studies of kinematic analysis of golf swing usually dealt with variations vertically. The purpose of the study was to examine the horizontal hip joints motion of the fifteen male professional golfers during driver swinging. Kinematic variables were calculated by the Kwon3D motion analysis program. Paired t-tests and one-way ANOVA were used to compare the hip height, distance, displacement, and position differences. Results showed that there were no hip height changes and no hip height differences between left and right hip from address to impact. The axis of the backswing was braced right hip, the axis of the downswing was moving left hip. Hips position at the top of the backswing showed that hips move to target prior to hands, which means the sequential motion of the chain linked body segments. From address to impact, left hip moving distance was longer than right hip(p<.001), but during the whole swing, right hip moving distance was longer than left hip(p<.001). Hip rotation angle to target line was $-48.14{\pm}9.32^{\circ}$ at top of the backswing, $40.88{\pm}8.44^{\circ}$ at impact, and $104.70{\pm}8.14^{\circ}$ at finish.

• 대한치과보철학회지
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• 제29권1호
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• pp.39-52
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• 1991

The purpose of this study were to compare the condylar path and the anterior angle of glenoid fossae, and analyze the condylar path, and classify the patterns of condylar path. Thirty-three male and female dental students with normal occlusion and masticatory system ranging in age from 24 to 27, without present symptoms and any history of TM joint disturbance, were selected for this study. Then, sixty-six TM joint were examed. Transcranial radiographs of TM joint and Cephalometric radiographs under mandibular protrusive movement were obtained. They were taken at six positions on protrusive movement. The results obtained were as follows : 1. The sequence of the frequeny of condylar movement patterns were concave curve, "S"shape curve, convex curve, and reverse "S"shape. 2. The horizontal distance of the greatest changed position of condylar angle averaged 2.6mm. 3. The condylar path angle averaged 36.91 degree. 4. The angle of the anterior slope of glenoid fossae averaged 37.28 degree. 5. The distance fo condylar movement averaged 5.98mm and the distance of condylar horizontal movement averaged 4.71mm. 6. The slope of articular eminence was correlated to the condyalr path and three were no significant differences between right and left side of the anterior slope of articular eminence, and the condyalr path angle.

• 한국환경복원기술학회지
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• 제13권6호
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• pp.1-12
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• 2010

This study aims at analyzing the development status of surroundings of natural environment conservation areas and securing an adequate distance from development activities to conserve natural environment conservation areas efficiently or developing an improvement plan for setting conservation areas. Findings from the study shows that 1) rather than simply designating a legal natural environment conservation area, a conceptual scope approach of a "core area", "buffer area", and "transition area" such as in zoning of a "biosphere reserve" by UNESCO is recommended; 2) when setting an adequate range in a natural environment conservation area, it should be set by fully considering locational situation and the regional and environmental features of surroundings rather than setting a certain distance uniformly; 3) instead of designating wetlands only as a conservation area, entry and exit areas should be also included as buffer areas and in the case of wild animals, not only habitats but also feeding areas should be designated as conservation areas; and 4) an adequate horizontal separation space is important in the case of ground development, but for natural resources related to subterranean water and geological situation such as wetlands, an adequate vertical separation space should be fully considered.

• 전자공학회논문지
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• 제52권4호
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• pp.23-29
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• 2015

본 논문에서는 수중 위치 추적(Underwater Localization)을 위한 수평거리 추정 방식 중 음선의 각도 변화를 이용하는 방식을 개선하는 Look-up Table(LUT)를 사용하는 방식을 제안하고 기존 방식과의 연산속도 및 수평거리 오차를 비교한다. LUT를 사용하여 추정하는 방식은 수신기의 음파 도달 시간(Time of arrival : ToA)과 깊이에 따른 Sound Speed Profile(SSP)을 이용하여 만들어진 수평 거리-ToA table을 이용한다. 결과적으로, 음선의 각도 변화를 이용하는 방식에 비해 수평거리 추정오차는 다소 증가하게 되지만, 수신된 ToA에 대응되는 수평거리를 사용한다는 점에서 실시간으로 각도 변화를 추정하는 기존방식에 비하여 매우 빠른 처리가 가능하다.

• 제어로봇시스템학회논문지
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• 제20권11호
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• pp.1153-1163
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• 2014

An efficient 3D SLAM (Simultaneous Localization and Map Building) method is developed for urban building environments using a tilted 2D LRF (Laser Range Finder), in which a 3D map is composed of perpendicular/horizontal planar polygons. While the mobile robot is moving, from the LRF scan distance data in each scan period, line segments on the scan plane are successively extracted. We propose an "expected line segment" concept for matching: to add each of these scan line segments to the most suitable line segment group for each perpendicular/horizontal planar polygon in the 3D map. After performing 2D localization to determine the pose of the mobile robot, we construct updated perpendicular/horizontal infinite planes and then determine their boundaries to obtain the perpendicular/horizontal planar polygons which constitute our 3D map. Finally, the proposed SLAM algorithm is validated via extensive simulations and experiments.

• Journal of the Optical Society of Korea
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• 제5권2호
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• pp.60-66
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• 2001

The authors discuss a prototype stylus profilometer designed to measure large optics. It consists of a low contact force type probe system, laser reference system, interferometric distance measurement system, and horizontal driving system. The probe contacts the surface ; the height and the horizontal distances of the measurement points are measured by the interferometer. The freely propagated laser beam provides the reference line during the measurement. The developed stylus profilometry shows only $\pm$60 nm of P-V error for the 157 mm diameter spherical mirror.