• 한국지반공학회:학술대회논문집
• /
• 한국지반공학회 2003년도 봄 학술발표회 논문집
• /
• pp.503-508
• /
• 2003

In this study, we peformed ahead a field geological investigation, boring investigation for slope stability analysis in large scale slope failure area. But the geological stratum was not clearly grasped, because ground was very disturbed by large scale Granite intrusion. Furthermore, the existing test data was not pertinent to the large scale Granite intrusion site like here. Therefore, various kind of field test were performed to grasp clearly for geological stratum. And the results of back analysis, various kind tests used to slope stability analysis.

• 한국초전도ㆍ저온공학회논문지
• /
• 제2권2호
• /
• pp.15-19
• /
• 2000

The stability of variable cross-sectional area HTS current lead is considered. The cross-sectional area is varied to have a constant safety factor which is defined as the ratio of operating current and critical current of superconductor. As the constant area HTS lead, the variable cross-sectional area HTS lead also has three steady states above the bifurcation point and only one steady state below the bifurcation point. The temperature profiles and current sharing ratios for each steady state are calculated. The heat dissipation into cryogenic system for super-conducting, intermediate, and upper states are compared. For Bi-2333 sheathed with silver-gold alloy 2m length of current lead, and the maximum temperature of upper state seems to be burn-out free below 5m length.

• 복식
• /
• 제58권6호
• /
• pp.54-68
• /
• 2008

The purpose of this study is to investigate the effect of dot pattern size(0.8, 1.8, 2.5, 5, 8), color combination(BG/R, Y/B), area-ratio on image formation. Sets of stimulus and response scales(7 point semantic) were used as experimental materials. The stimuli were 20 color pictures manipulated with the combination of dot pattern size, color combination, and area-ratio using computer simulation. The subjects were 240 female undergraduates living in Gyeongnam-do. Image factor of the stimulus was composed of 5 different components, visibility, attractiveness, cuteness, stability and high class image. In the cuteness, color combination, dot pattern size showed independent effect. In the stability, area-ratio, dot pattern size showed independent effect. Interaction effects of color and area-ratio combination was significant on cuteness. For visibility image 8cm yellow dot/blue background, for attractiveness image BG/R coloration, for cuteness image Y/B coloration and for stability image 0.8cm yellow dot/blue background were effective. According to the variation of dot pattern size, color combination and area-ratio, it was investigated that the images for a dress wearer were expressed diversely, were shown differently in image dimensions, and could be produced to different images.

• Geomechanics and Engineering
• /
• 제35권4호
• /
• pp.395-409
• /
• 2023

Long-span suspension bridges have tunnel anchor systems to maintain stable cables. More investigations are required to determine how closely tunnel excavation beneath the tunnel anchor impacts the stability of the tunnel anchor. In order to investigate the impact of the adjacent tunnel's excavation on the stability of the tunnel anchor, a large-span suspension bridge tunnel anchor is utilised as an example in a three-dimensional numerical simulation approach. In order to explore the deformation control mechanism, orthogonal tests are employed to pinpoint the major impacting elements. The construction of an advanced pipe shed, strengthening the primary support. Moreover, according to the findings the grouting reinforcement of the surrounding rock, have a significant control effect on the settlement of the tunnel vault and plug body. However, reducing the lag distance of the secondary lining does not have such big influence. The greatest way to control tunnel vault settling is to use the grout reinforcement, which increases the bearing capacity and strength of the surrounding rock. This greatly minimizes the size of the tunnel excavation disturbance area. Advanced pipe shed can not only increase the surrounding rock's bearing capacity at the pipe shed, but can also prevent the tunnel vault from connecting with the disturbance area at the bottom of the anchorage tunnel, reduce the range of shear failure area outside the anchorage tunnel, and have the best impact on the plug body's settlement control.

• 자원환경지질
• /
• 제33권1호
• /
• pp.77-88
• /
• 2000

The goal of this study is to assess the spatial distribution of natural slopes and cutting slopes under would-be development. For this goal, a quantitative slope stability analysis method using GIS integrated with a computer program was developed. Through field investigations, the discontinuity parameters were collected such as orientation of discontinuity, persistence, spacing, JRC, JCS, and water depth. The distributions were interpolated from the ordinary kriging method in ARC/INFO GIS after variogram analysis. The layers showing all parameters needed for limit equilibrium analysis were constructed. The final layer using GIS works composed of 162,352 polygons, that is, unit slopes. The rock slope stability analysis program was coded by C++ language. This program can calculate geometrical vectors related to rock block failures using input orientation data and direction and dimension of strength to occur failure. Also, this can calculate shear strength of joints through empirical equations and quantitative factors of safety. This methodology was applied to the study area which is located in Jaecheon city and Danyang-gun of the northeastern Keumsu is about 135$km^2$. As a result, the study area was entirely stable but unstable, that is, factor of safety less than 1.0dominantly at the slopes near Keumsil, Daejangri, Keumsungmyun and Sojugol, Mt. Dongsan, Juksongmyun by the natural slope stability analysis. Assuming the cutting slope showing the same direction immediate, and quantitative analysis of factors of safety for a regional area could be conducted through GIS integrated with a computer program of limit equilibrium.

• 한국융합학회논문지
• /
• 제11권4호
• /
• pp.63-69
• /
• 2020

본 연구는 복부압박벨트가 만성 뇌졸중 환자의 안정성한계와 보행 변수에 즉각적인 효과를 알아보기 위해 실시하였다. 뇌졸중 환자 30명을 모집하여 복부압박벨트 착용 전과 복부압박벨트 착용 후 변화를 확인하였다. 측정은 균형변수인 안정성한계(limited of stability), 시공간적 보행 변수(spatiotemporal gait parameter)를 측정하였다. 복부압박벨트 착용 후 마비측, 비마비측, 전방, 후방 이동면적이 유의하게 증가하였고(p<.05), 시간적 보행 변수인 분속수(cadence), 보행속도(gait velocity), 공간적 보행변수인 보폭(stride length)이 유의하게 증가하였다(p<.05). 본 연구를 통해 복부압박벨트 착용은 뇌졸중 환자에게 균형과 보행 기능 개선에 즉각적인 효과가 있다는 것을 확인할 수 있었다. 향후 연구에서는 뇌졸중 환자의 균형과 보행 기능 개선에 효율적인 복부압박 수준과 중재기간에 대한 연구가 필요하다.

• 지질공학
• /
• 제33권4호
• /
• pp.689-699
• /
• 2023

Assessing ground stability is critical to the construction of underground transportation infrastructure. Surface displacement is a key indicator of ground stability, and can be measured using interferometric synthetic aperture radar (InSAR). This study measured time-series surface displacement using permanent scatterer InSAR applied to Sentinel-1 SAR images acquired from January 2017 to June 2023 for the area around a deep underground expressway under construction to connect Mandeok-dong and Centum City in Busan, South Korea. Regions of seasonal subsidence and uplift were identified, as were regions with severe subsidence after summer 2022. To evaluate stability of the ground in the construction area, the mean displacement velocity, final surface displacement, cumulative surface displacement, and difference between minimum and maximum surface displacement were analyzed. Considering the time-series surface displacement characteristics of the study area, the difference between minimum and maximum surface displacement since June 2022 was found to be the most suitable parameter for evaluating ground stability. The results identified highly unstable ground in the construction area as being to the north of the mid-lower reaches of the Oncheon-cheon River and to the west of the Suyeong River at the point where both rivers meet, with the difference between minimum and maximum surface displacement of 40~60 mm.

• 척추신경추나의학회지
• /
• 제8권2호
• /
• pp.39-46
• /
• 2013

Objectives : To identify the association between cross-sectional area of lumbar regional muscle and stability(ST), center of pressure(COP) assessed by tetrax. Methods : Patients(n=55) who had taken L-SPINE MRI and Tetrax(Sunlight, Israel) were analyzed retrospectively. To evaluate the cross-sectional area of lumbar regional muscle, L-SPINE MRI was used. Data of ST, COP were accumulated by using dynamic equilibrium analysis by Tetrax. Of the lumbar regional muscles, the Psoas muscles and the Paraspinalis muscles were examined. Using Pearson correlation, we analyzed COP, ST and the difference between the cross-sectional area of lumbar regional muscles. Results : The variance of cross-sectional area of both sides of Psoas muscle and COP had moderate positive correlation(r=0.621). Between variance of cross-sectional area of both sides of Paraspinalis and lumbar regional muscle and COP there was low positive correlation(r=0.287, r=0.329) ST also had low correlation with variance of cross-sectional area of both sides of Psoas muscle. Conclusion : The variance of cross-sectional area between both sides of Psoas muscle had moderate correlation with COP.

• 대한조선학회논문집
• /
• 제44권3호
• /
• pp.323-331
• /
• 2007

Proposed Manta-type Unmanned Undersea Vehicle(UUV) turned out to have the tendency of dynamic instability in vertical plane, and moreover to have that of so strong dynamic stability in horizontal plane as to cause another problem in turning motion due to negative value of sway damping lever. The authors discussed the changes in appendage design for improvement of dynamic stability of UUV in vertical and horizontal planes. As a result, the dynamic stability in vertical plane was improved by increasing the area of horizontal stern planes. and the dynamic stability in horizontal plane was also improved by removal of lower vertical plate and by adjusting the area and position of upper vertical plate simultaneously.

• 대한조선학회논문집
• /
• 제33권4호
• /
• pp.1-14
• /
• 1996

IMO 조종성잠정기준 4가지 항목중, 특히 비대선형의 경우 침로안정성이 문제시될 수 있다. 본 연구의 목적은 타의 스팬길이에 따른 면적 변화가 침로안정성에 미치는 영향을 조사함으로써, 타면적 증감에 의한 침로안정성 개선 방법을 모색하고자 한다. 본 연구에서는 타직압력과 관련된 실험 정수들과 조종유체력미계수와의 관계를 정식화하였고, 타직압력과 관련된 각종 구속모형시험을 실시하여 타면적 변화에 따른 조정유체력미계수의 변화를 구하고, 이로부터 침로안정성을 비교, 분석하였다. 또한 조종성 시뮬레이션 기법을 이용하여 타면적 증감에 따른 조종성능 개선 효과를 검토하였다. 연구 결과, 타면적 증가는 침로안정성을 저해할 가능성이 있으며, 그 원인은 스팬길이 증가로 인한 타 상부와 선미 오버행 하부의 공간이 작아지기 때문이다. 이 공간은 조종운동시정류계수에 큰 영향을 미치며, 이것이 침로안정성과 관련된다는 것을 알 수 있었다.