• 터널과지하공간
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• 제4권1호
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• pp.55-62
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• 1994

The hydraulic fracturing in a field site was performed for the measurement of in-situ stresses. For the estimation of the effect of a preexisting inclined fracture, the test on a preexisting fracture zone was also conducted. From the measurements at three shallow depths, the ratios of max. to min. horizontal stress showed the range of 1.19-1.56 and the K values showed the range of 2.62-3.86. In case of a preexisting fracture with the inclination of 15 degrees, the stresses calculated as upper bound values by considering it. It seemed from this that the inclination less than 15 degrees had small effect on the stress calculation.

• Structural Engineering and Mechanics
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• 제76권6호
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• pp.725-736
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• 2020

In this work the mixed mode I/III fracture of sandstone has been studied experimentally and numerically. The experimental work used three-point bending specimens containing pre-existing cracks, machined at various inclination angles so as to achieve varying proportions of mode I to mode III loading. Dimensionless stress intensity factors were calculated using the extended finite element method (XFEM) for and compared with existing results from literature calculated using conventional finite element method. A total of 28 samples were used to conduct the fracture test with 4 specimens for each of 7 different inclination angles. The fracture load and the geometry of the fracture surface were obtained for different mode mixities. Prediction of the fracture loads and the geometry of the fracture surface were made using XFEM coupled with a cohesive zone model (CZM) and showed a good comparison with the experimental results.

• International Journal of Advanced Culture Technology
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• 제11권3호
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• pp.190-198
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• 2023

Sentiment analysis can be applied to all texts generated from websites, blogs, messengers, etc. The study fulfills an artificial intelligence sentiment analysis estimating visiting evaluation opinions (reviews) and visitor ratings, and suggests a deep learning model which foretells either an affirmative or a negative inclination for new reviews. This study operates review big data about Jeju tourist attractions which are extracted from Google from October 1st, 2021 to November 30th, 2021. The normalization data used in the propensity prediction modeling of this study were divided into training data and test data at a 7.5:2.5 ratio, and the CNN classification neural network was used for learning. The predictive model of the research indicates an accuracy of approximately 84.72%, which shows that it can upgrade performance in the future as evaluating its error rate and learning precision.

• Applied Biological Chemistry
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• 제33권4호
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• pp.307-314
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• 1990

Brassinosteroid는 특이한 생리작용을 갖는 식물의 신 생장조절물질로 주목을 받고 있으나, 아직 우리나라의 가장 중요한 작물인 벼의 brassinosteroid에 대해 연구된 바 없어, 일반계 품종의 벼를 대상으로 brassinosteroid활성물질의 검색을 시도하였다. 동진벼와 영산벼를 최고분얼기까지 재배하여 지상부를 수확하고, 유기용매로 추출하여 얻어진 추출물에서 rice lamina inclination test에 의한 생물검정법으로 활성이 인정되어, 활성본체의 구명과 정제의 목적으로 각각의 활성획분을 silica gel 흡착 chromatography, Sephadex LH-20 chromatography, charcoal 흡착 chromatography, preparative TLC, Bondesil chromatography 그리고 normal, reverse phase의 HPLC 등적 방법으로 분획하여 검정한 결과 2품종 모두 brassinosteroid활성물질을 생산하고 있으며, 또 2품종간의 endogenous brassinosteroid의 유사성이 인정되었다.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2005년도 춘계 학술발표회 논문집
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• pp.409-416
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• 2005

Design analysis for underground spaces requires evaluating stability related to tunnel collapses. A failure mode is one of the critical factors in the conventional methods of stability analysis. Therefore identification of failure modes is essential in securing safe construction in the phase of design analysis, instrumentation planning and implementation of reinforcing measures. In this study failure modes at the tunnel heading in granular soils are investigated using physical model tests and numerical simulation for various tunnel depths and ground surface inclinations. Test results indicated that the effect of depth and inclination of ground surface on a failure mode are significant. It is identified that, with an incase in depth, failure modes become localized in a region close to the tunnel. It is also known that an increase in the inclination of ground surface results in inclined and wide failure modes.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2004년도 춘계학술발표회
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• pp.50-57
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• 2004

In this study reinforcing effect of soil nailed-drilled shafts subjected to axial and lateral loads were evaluated. Special attention was given to the reinforcing effects of soil nails placed from the drilled shafts to surrounding weathered- and soft-rocks based on model tests, numerical analyses and load tests. The model tests and numerical analyses are conducted to analyze the reinforcing effect of various conditions of number, inclination, position and length. The results of 1/40 scale model tests and numerical analyses show that as the number of reinforcing level increases, the incremental effect of reinforcement tends to increase, whereas the reinforcing effect on relative position is negligible. In addition there is a reinforcing effect as the inclination angle increaes up to 30 degrees. Based on the results of tensile load tests, soil nailed-drilled shafts has a considerably smaller settlement to reach the ultimate level when compared with the result of un-reinforced drilled shafts. For compression tests, there is a reinforcing effect of about 200% measured.

• 한국도로학회논문집
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• 제19권1호
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• pp.21-28
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• 2017

PURPOSES : This paper presents a finite element model to accurately represent the soil-post interaction of single guardrail posts in sloping ground. In this study, the maximum lateral resistance of a guardrail post has been investigated under static and dynamic loadings, with respect given to several parameters including post shape, embedment depth, ground inclination, and embedment location of the steel post. METHODS : Because current analytical methods applied to horizontal ground, including Winkler's elastic spring model and the p-y curve method, cannot be directly applied to sloping ground, it is necessary to seek an alternative 3-D finite element model. For this purpose, a 3D FHWA soil model for road-base soils, as constructed using LS-DYNA, has been adopted to estimate the dynamic behavior of single guardrail posts using the pendulum drop test. RESULTS : For a laterally loaded guardrail post near slopes under static and dynamic loadings, the maximum lateral resistance of a guardrail post has been found to be reduced by approximately 12% and 13% relative to the static analysis and pendulum testing, respectively, due to the effects of ground inclination. CONCLUSIONS : It is expected that the proposed soil material model can be applied to guardrail systems installed near slopes.

• International Journal of Automotive Technology
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• 제7권6호
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• pp.715-720
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• 2006

This research investigates injury values and vehicle deformation for vehicle frontal crash compatibility. To investigate compatibility in an individual case, it is possible to impact two vehicles and evaluate the injury values and deformations in both vehicles. In this study, four tests were conducted to evaluate compatibility. A large and mini vehicle were subjected to a frontal car-to-car crash test at a speed of 48.3 km/h with an offset of 40%. An inclination car-to-car crash test using the large and small vehicle were conducted at 30 km/h at a $30^{\circ}$ angle. The results of the 48.3 km/h, car-to-car frontal crash revealed extremely high injury values on the chest and upper leg of the Hybrid III 50% driver dummy with seatbelt in the mini vehicle compared to the large vehicle. For the 30 km/h, car-to-car inclination crash, however, injury values in the small vehicle were 1.5 times higher compared to the large vehicle.

• 한국정보시스템학회지:정보시스템연구
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• 제8권2호
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• pp.129-143
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• 1999

A great number of companies are currently examining the opportunities made available through the internet. This research aims to identify the factors that influence the adoption of the internet market. The innovation-IT-diffusion theory provide the theoretical foundation for this study. Seven factors were found to influence the adoption level of the internet market. They are top management support, cost efficiency, inclination toward new technology, absorptive capacity, institutional support, competitors move and customer pressure. Nonparametric test was used to test hypotheses. The results shows that top management support is the most important factor, and institutional support is not related to the adoption of the internet market.

• 한국항해항만학회지
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• 제37권2호
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• pp.155-163
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• 2013

이 연구에서는 전단하중을 받는 부유식 콘크리트 구조물 모듈 접합부의 구조거동 실험연구를 수행하였다. 모듈 접합부 전단키의 균열 양상, 전단거동 및 전단강도를 파악하였다. 전단강도의 영향을 파악하기 위해 전단키의 경사각도, 횡방향 구속응력 및 콘크리트의 압축강도 등을 실험변수로 고려하였다. 전단키의 경사각도가 증가함에 따라 접합부의 전단강도가 증가하였다. 또한, 구속응력이 증가함에 따라 전단키의 전단강도가 증가하였다. 실험변수에 따른 전단거동 실험결과를 토대로 접합부의 전단강도 평가식을 제안하였으며, 제안식에 의한 전단강도 예측값은 실험값에 근접하는 것으로 나타났다.