• 농업과학연구
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• 제49권4호
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• pp.707-717
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• 2022

As the variability of recent rainfall is increasing, it is becoming important to recognize the possibility of changes in the current reservoir state in advance and to inspect the stability based on accurate evaluation standards. However, the evaluation standards for the state change factors of reservoirs are still not suitable for agricultural reservoirs and thus much improvement is needed. Therefore, in this study, the evaluation criteria for state change factors specialized for small reservoirs were categorized and standards were prepared by considering factors that may cause state changes on the dam crest, upstream slope, and downstream slope of the embankment. The categorized results were configured based on the number of mentions of the precision safety inspection report on major defects in 102 reservoirs and the defect factors found in field investigations. The findings of the study indicated that the current state change standards require many revisions for excessive or unnecessary state change factors in the reservoir. Specifically, the deletion of measurement gauges not applicable to the reservoir, the addition of defects found in the reservoir, and the scope of use of the term were proposed. The results of this study can contribute to efficient system operation and management by improving the deficiencies in the system and introducing a new state change factor.

• 한국안전학회지
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• 제18권3호
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• pp.126-130
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• 2003

The term stress is currently used to cover a wide variety of phenomena, ranging from physical to social and cultural factors. The term has defined psychological stress as an imbalance between perceived or subjective demand and perceived response capability. The behavior science model has provided the accident proneness through the life change unit factors considering human behavior, life style, ideas, culture, and psychological state. Therefore, this paper presents the Korean life change unit model through statistical testing with the proposed life change unit factors on the unmarried workers living in the middle area. The proposed model can be simply used in real fields in order to minimize the industrial accidents.

• Bulletin of the Korean Chemical Society
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• 제13권6호
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• pp.613-620
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• 1992

The solvent-dependent photophysical properties of 2-biphenylcarboxylic acid (2BPCA) and 4-biphenylcarboxylic acid(4BPCA), which have a pre-twisted conformation in the ground state, have been investigated. The fluorescence spectra of 4BPCA show vibrational structure with a non-mirror image to the absorption spectra in nonpolar solvent while those of 2BPCA show no structure even in nonpolar solvents. As the solvent polarity increases, the fluorescence spectra become diffuse and broad with a strong red shift resulting in the large Stokes shift. The large fluorescence Stokes shift of BPCA's in polar solvent is also partially due to an intramolecular charge transfer (ICT) interaction in the excited state, as demonstrated by the large dipole moment in the excited state (7.6-10.6 D). The fluorescence decay behaviors of BPCA's (decay-times and their pre-exponential factors) also depend on solvent polarity in agreement with the solvent-dependent properties of the steady-state fluorecence. The data have been discussed in terms of change in the excited-state potential energy surface with respect to change of the dihedral angle of biphenyl moiety.

• 반도체디스플레이기술학회지
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• 제23권1호
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• pp.52-55
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• 2024

In this paper, a state change study was conducted through Frequency Domain Reflectometry (FDR) technology for the process chamber of plasma equipment for semiconductor manufacturing. In the experiment, by direct connecting the network analyzer to the RF matcher input of the 300 mm plasma enhanced chemical vapor deposition (PECVD) chamber, S11 was measured in a situation where plasma was not applied, and the frequency domain reacting to the chamber state change was searched. Response factors to changes in the status, such as temperature, spacing of the heating chuck, internal pressure difference, and process gas supply state were confirmed. Through this, the frequency domain in which a change in the reflection value was detected through repeated experiments. The reliability of the measured micro-displacement was verified through reproducibility experiments.

• International Journal of Costume and Fashion
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• 제15권1호
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• pp.1-18
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• 2015

The ethnic dress of Germany's Black Forest, called Tracht, dates back to the 16th century. Although most people living within the Black Forest do not presently wear Trachten, some persistence in this tradition exists. This study explored the factors that have supported the persistence of the Trachten tradition, specifically related to the wearing and crafting of Trachten by women, in a contemporary society. A qualitative, ethnographic approach was adopted. Data were collected via observations and interviews in the Black Forest. Thematic analyses revealed that the maintenance of the Trachten tradition was linked to varied factors that revolved around the overarching themes of both persistence and change. Interpretations were supported by theory proposing that ethnic dress is not static, but rather, changes across space and time in ways that enable its persistence. The persistence of the Trachten tradition was linked to formalized practice, meaningful identities, and desires to preserve and promote local culture. Additionally, the persistence of the Trachten tradition was fostered by change in the tradition, including the conceptualization of Trachten as a "lived practice" and the negotiation of Trachten authenticity.

• 한국해안·해양공학회논문집
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• 제31권6호
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• pp.351-355
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• 2019

무공케이슨 방파제의 한계상태설계를 위한 하중저항계수를 제시하였다. 전국 항만의 16개 방파제에 대한 신뢰성해석을 수행하여 부분안전계수를 산출하였으며 이를 하중과 저항계수로 전환하였다. 개별적으로 구한 하중저항계수에 최적화기법을 적용하여 최종 하중저항계수를 보정하였다. 최종적으로 얻은 하중저항계수를 이용하여 방파제를 재설계한 후 목표수준을 만족하는지 검증하였다. 목표신뢰도수준의 변화에 따른 하중저항계수를 제시하여 한계상태설계가 용이하도록 하였다.

• 한국측량학회:학술대회논문집
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• 한국측량학회 2004년도 추계학술발표회 논문집
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• pp.385-388
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• 2004

Many environmental destruction factors are accompanied in the mining development work and the secondary environmental disaster and the induction factors are inhered. We aquired digital data using aerial photogrammetry to analyze the terrain current situation according to the development situation of the mining restoration plan. We made the object area to 3D model and conducted terrian change monitoring. Then, we presented the decision-making information to improve rational management according to the original state plan.

• 한국항해항만학회지
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• 제34권6호
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• pp.471-477
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• 2010

최근 IMO에서는 항만국통제 우선점검 평가에 해양사고율을 평가항목에 추가로 포함하는 것에 대해 검토하고 있다. 본 연구는 절대 평가법을 이용한 항만국통제 우선점검을 위한 대상선박 선정법을 제안하였다. 이를 위해 항만국통제 우선점검 평가의 단점을 보완하고 합리적인 평가법으로 널리 알려진 절대평가법을 이용하였다. 또한 이 방법과 기존 도쿄MOU의 평가방법을 10척에 윌콕슨 검정으로 비교하여 유효성을 확인하였으며, 평가항목의 평가치를 변경하는 실험을 통해 PSC 우선점검 순위변동을 조사하였다. 그 결과 출항정지, 선령, 해양사고 등 평가항목의 가중치가 높은 평가치가 순위변동에 영향이 큰 것으로 나타나 이 항목들을 중점 관리하여 PSC를 예방할 필요가 있다는 점이 확인되었다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2004년도 하계학술대회 논문집 Vol.5 No.2
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• pp.1308-1311
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• 2004

It is very important that get polishing characteristic that to be stable that accomplish planarization of high efficiency in chemical mechanical polishing, and there is repeatability Groove of pad causes much effects in flow of slurry among various factors that influence in polishing characteristic, is expected to cause change of lubrication state and polishing characteristic in contact between wafer and pad. Therefore, divided factors of pad groove by groove pattern, groove profile, groove dimensions. This research wishes to study effect that dimension of pad groove gets in polishing performance. When changed dimension (width, depth, pitch of groove) of groove, measured change of removal rate and friction force. According as groove dimension changes, could confirm that removal rate and friction force change. While result of this experiment studies effect of pad groove in CMP, it is expected to become small help.

• 한국전산구조공학회논문집
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• 제30권3호
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• pp.215-222
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• 2017

프리스트레스트 보의 인장력 변화에 따른 콘크리트 응력 수준을 평가하기 위하여, 초음파를 이용하는 기존의 방법보다 개선된 비선형 초음파 공진 기법의 도입을 제안하였다. 이는 동일하게 초음파를 사용하는 선형의 기법보다 월등히 높은 민감도를 보이므로 초기 상태의 응력 평가에도 유리하다. 비선형 초음파 공진 기법은 초음파 통과시 매질 상태에 따른 공진 주파수의 변화의 정도로부터 계산되는 비선형 인자의 값을 측정하며, 측정 결과는 콘크리트의 응력 상태와도 밀접한 연관을 갖는다. 본 연구에서는 유압 펌프를 통한 인장력 작용에 따른 비선형 인자의 측정을 수행함으로써 두 인자 사이에 밀접한 연관성이 있음을 확인하고, 반복적인 하중 이력의 작용이 비선형 인자의 변화에 미치는 영향을 분석하였다. 추가적으로, 선형 초음파 전파 속도 측정 결과를 비교하여 제안한 방법의 민감도를 검증하였다. 측정 결과를 통해 프리스트레스트 보의 콘크리트 응력 수준 평가를 위한 비선형 초음파 공진 기법의 적용 가능성을 확인하였다.