• 한국정밀공학회지
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• 제8권2호
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• pp.89-105
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• 1991

A method to apply the approximation formulae[1] for tooth fillet and root stresses of a thin-rimmed rack to the calculation of stress state of thin-rimmed external and internal spur gears is introduced. The stress values by the method proposed in this paper have shown good agreement with those by the REM analysis and also by the stress measurement of strain survey investigation. By this method, reliable stress state at tooth fillet and root areas in the thin-rimmed external and internal spur gears can be easily calculated, and a practical design method for the bending strength of such thin-rimmed gears is established.

• 한국자동차공학회논문집
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• 제9권3호
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• pp.131-142
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• 2001

A wrinkling is the instability phenomenon influenced by material properties, shape geometry, forming conditions, stress state, etc. The wrinkling is considered as a critical defect in appearance of product. Many wrinkling prediction methods using thickness strain distribution and farming analysis have been proposed. The wrinkling, however, is not easily predicted precisely by these methods. In this study, the region in the biaxial plane stress state is modeled with a rectangular plate introducing the effective dimension, and critical stress values for the wrinkling are calculated. Prediction index for the wrinkling is then evaluated by normalizing the actual stress with respect to the critical stress. In order to show the validity and efficiency of the method proposed, the wrinkling prediction for a squared sheet in the uniaxial tensile stress and auto-body front finder panel is performed.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2003년도 International Meeting on Information Display
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• pp.263-265
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• 2003

Stressed liquid crystals, SLCs, consist of a lowdensity polymer network dispersed in a nematic host. We induced stress by shearing the material. Alignment layers are not required because the liquid crystal director uniformly aligns along the direction of shear. The shearing stress also eliminates light scattering and results in sub-millisecond switching speeds, making them good candidates for video display applications.

• Geomechanics and Engineering
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• 제32권3호
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• pp.245-254
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• 2023

Through qualitative analysis and quantitative analysis, the contradictory conclusions about the stability of the settled goaf with two-layer coal seams subject to building load were obtained. Therefore, it is necessary to combine the additional stress method and numerical simulation to further analyze the foundation stability. Through borehole analysis and empirical formula analogy, the height of water-conducting fracture zone in No.4 coal and No.9 coal were obtained, providing the calculation range of water-conducting fracture zone for numerical simulation. To ensure the accuracy of the elastic modulus of broken gangue, the stress-strain curve were obtained by broken gangue compression test in dried state of No.4 coal seam and in soaking state of No.9 coal seam. To ensure the rationality of the numerical simulation results, the actual measured subsidence data were retrieved by numerical simulation. FISH language was used to analyze the maximum building load on the surface and determine the influence depth of building load on the foundation. The critical building load was 0.16 MPa of No.4 settled goaf and was 1.6 MPa of No.9 settled goaf. The additional stress affected the water-conducting fracture zone obviously, resulted in the subsidence of water-conducting fracture zone was greater than that of bending subsidence zone. In this paper, the additional stress method was analyzed by numerical simulation method, which can provide a new analysis method for the treatment and utilization of the settled goaf.

• 한국전기전자재료학회논문지
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• 제31권6호
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• pp.372-376
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• 2018

The effects of off-state bias stress on the characteristics of p-type poly-Si TFT were investigated. To reduce the gate-induced drain leakage (GIDL) current, the off-state bias stress was changed by varying Vgs and Vds. After application of the off-state bias stress, the Vgs causing GIDL current was dramatically increased from 1 to 10 V, and thus, the Vgs margin to turn off the TFT was improved. The on-current and subthreshold swing in the aged TFT was maintained. We performed a technology computer-aided design (TCAD) simulation to describe the aged characteristics. The aged-transfer characteristics were well described by the local charge trapping. The activation energy of the GIDL current was measured for the pristine and aged characteristics. The reduced GIDL current was mainly a thermionic field-emission current.

• 디지털융복합연구
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• 제17권10호
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• pp.313-320
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• 2019

본 연구는 병원여성행정직의 주관적행복감, 직무소진 및 사회심리적 스트레스와 상태불안간의 관련성을 파악하고 상태불안에 미치는 융복합적인 영향을 규명하였다. 조사기간은 2018년 7월 4일부터 2018년 7월 25일까지였으며, 조사대상은 임의로 선정한 J지역 소재 24개 병원에서 무작위로 추출한 여성행정직 226명으로 하였고, 자료수집은 구조화된 무기명 자기기입식 설문지를 사용하였다. 상태불안은 주관적행복감과는 음의 상관관계를, 직무소진 및 사회심리적 스트레스와는 양의 상관관계를 보였다. 공분산구조분석 결과, 주관적행복감이 낮을수록, 직무소진 및 사회심리적 스트레스가 높을수록 상태불안을 높이는 것으로 나타났다. 분석결과를 볼 때, 병원여성행정직의 상태불안을 낮추기 위해서는 주관적행복감을 높이고, 직무소진 및 사회심리적 스트레스를 낮추는 노력이 필요하다. 이러한 결과는 병원여성행정직의 상태불안을 낮추는 산업보건교육 및 병원내부고객관리에 활용이 기대된다. 향후연구에서는 병원여성행정직의 상태불안에 영향을 미치는 융복합적인 추가적인 요인에 대한 조사가 필요하다.

• 대한간호학회지
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• 제46권2호
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• pp.194-206
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• 2016

Purpose: The purpose of this study was to examine a Korean Mindfulness Based Stress Reduction (K-MBSR) program for middle aged women and to verify the program's effectiveness on stress, stress coping style, depression, anger and sleep. Methods: Fifty-two women aged from 40 to 59 (26 in the experimental group and 26 in the control group) from G city participated in the study. Data were collected from February 13 to April 3, 2013. The experimental group received 8 sessions, scheduled once a week, with each session lasting two and a half hours. Outcome variables included stress, stress coping style, depression, anger, sleep and a physiological measure (EEG). Results: There were significant decreases for stress (t=-2.14, p=.037), depression (t=-2.64, p=.011), state trait anger (t=-3.79, p<.001) in the experimental group compared to the control group. Conclusion: The findings in this study indicate that the K-MBSR program is an effective program to decrease stress, depression, and state trait anger in middle aged women.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2001년도 가을 학술발표회 논문집
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• pp.483-488
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• 2001

The RC beams subjected to bending and shear are an important substructure. After flexural cracking, the internal stress state in the beam could not be explained by the classical beam theory. In this study the internal force state factor is introduced to explain the stress state change in the RC beams. The internal force state factor of uniform load was expanded by superposition method using infernal force state factor of point load. As the load types change, the operator that would be calculated the internal force state factor was proposed.

• 한국해양공학회지
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• 제22권6호
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• pp.52-57
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• 2008

The short-term high temperature creep rupture behavior of Ni-based Alloy718 steel was investigated at the elevated temperatures range of 550 to $700^{\circ}C$ under constant stress conditions. The creep rupture characteristics such as creep stress, rupture time, steady state creep rate, and initial strain were evaluated. Creep stress has a quantitative correlation between creep rupture tim and steady state creep rate. The stress exponents (n, m) of the experimental data at 550, 600, 650 and $700^{\circ}C$ were derived as 33.5, -24.9, 26.1, -21.2, 16.8, -12.8 and 10, -8.2, respectively. The stress exponent decreased with increasing creep temperature. The creep lift prediction was derived by the Larson-Miller parameter (LMP) method and the resultant equation was obtained as follows: T($logt_r$+20)=-0.00252 ${\sigma}^2$-1.377${\sigma}$+-22718.

• 한국터널지하공간학회 논문집
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• 제5권2호
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• pp.147-159
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• 2003

90년대 이후 지하 암반 구조물의 수요가 증가함에 따라 시공 전 설계 단계에서 요구되는 암반내 초기응력에 대한 정량적 정보를 얻기 위해 현장 초기 응력 측정이 광범위하게 수행되고 있다. 제안된 여러 측정법들 중 현장 적용성 면에서 큰 장점을 가진 수압파쇄법이 국내에서는 대표적으로 적용되고 있다. 본 논문에서는 평탄한 지형조건으로 이루어진 서울 중심부 편마암 지역내 저심도 구간의 11개 시추공을 대상으로 수압파쇄법에 의해 구해진 초기응력 측정자료와 수평응력의 크기, 방향성과 심도별 변화 그리고 측압계수 분포 등 과업구간 암반 내 초기응력장의 제반 분포 특성에 대해 논의하고자 한다.