• 대한화장품학회지
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• 제26권1호
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• pp.213-232
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• 2000

Cetostearyl alcohol has been incorporated into cosmetic or pharmaceutial emulsions to give them an appropriate consistency and a long term stability. It is well known that cetostearyl alcohol forms a gel phase with a nonionic surfactant in an aqueous system, and the properties of the gel phase depend on several factors such as the ratio of fatty alcohols. The aim of the present Paper is to investigate the effect of the structural difference of the lipophilic part of surfactants on the stability of the gel phase in the nonionic surfactant / cetostearyl alcohol / water ternary systems using differential scanning calorimeter. It is concluded that the gel phase formed by the surfactant having the bended alkyl chain is more unstable than that formed by the case of the straight alkyl chain, and we discussed the reason why the former is more unstable after long term storage by means of the measurements of the ${\Delta}$H.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제41권3호
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• pp.156-164
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• 2015

Bilateral sagittal split ramus osteotomy is considered a standard technique in mandibular orthognathic surgeries to reduce unexpected bilateral stress in the temporomandibular joints. Unilateral sagittal split ramus osteotomy (USSO) was recently introduced to correct facial asymmetry caused by asymmetric mandibular prognathism and has shown favorable outcomes. If unilateral surgery could guarantee long-term postoperative stability as well as favorable results, operation time and the incidence of postoperative complications could be reduced compared to those in bilateral surgery. This report highlights three consecutive cases with long-term follow-up in which USSO was used to correct asymmetric mandibular prognathism. Long-term postoperative changes in the condylar contour and ramus and condylar head length were analyzed using routine radiography and computed tomography. In addition, prior USSO studies were reviewed to outline clear criteria for applying this technique. In conclusion, patients showing functional-type asymmetry with predicted unilateral mandibular movement of less than 7 mm can be considered suitable candidates for USSO-based correction of asymmetric mandibular prognathism with or without maxillary arch surgeries.

• 한국지반공학회논문집
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• 제37권8호
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• pp.25-35
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• 2021

현재 국내에서는 비탈면 및 구조물 안정성 확보를 목적으로 네일, 록볼트 등과 함께 그라운드 앵커 공법을 사용하고 있다. 이 중 장기목적으로 사용되는 영구앵커의 경우 사용기간 중 지지력과 내구성이 확보되어야 하나, 최근 연구 결과에 따르면 장기거동에 따른 잔존 긴장력 감소와 비탈면 변형 등의 현상이 보고되고 있다. 이와 같은 잔존 긴장력 감소 문제는 앞으로 지속적으로 증가될 것으로 전망되며, 이로 인한 유지관리 비용 증가 등의 문제가 불가피할 것으로 보인다. 이에 본 연구에서는 국내·외 문헌연구를 통해 영구앵커의 긴장력에 영향을 미치는 요인들을 파악하였으며, 과거 수행된 하중계 모니터링 자료를 분석한 선행연구들을 조사하였다. 이후, 이를 기초자료로 활용하여 실제 현장에서 수집한 하중계 계측자료를 분석하여 앵커의 긴장력 감소현황을 파악하였고, 그 장기하중감소특성을 분석하였다. 마지막으로 앞의 내용을 종합하여, 설치 직후 100일 부근의 단기 데이터를 통해 영구앵커의 장기하중감소특성을 예측하는 기법을 제안하였다.

• Communications for Statistical Applications and Methods
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• 제18권4호
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• pp.495-505
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• 2011

본 연구에서는 표본의 일부를 단계적으로 증가시켜 가며 반복적으로 추정된 장기모수의 시간경로를 파악하는 방식으로 변수들 간 장기균형관계의 안정성에 대해 통계적으로 검정해 보았다. 안정성 귀무가설이 기각되는 구간에는 더미변수를 사용해 전체 연구기간에 걸쳐 안정성을 회복시키고 타당한 공적분관계를 도출해 보았으며, 오차수정항에 대한 분석결과는 더미변수가 공적분관계의 구조변화를 반영하는 것으로 나타났다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1987년도 전기.전자공학 학술대회 논문집(I)
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• pp.662-666
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• 1987

• 한국방사성폐기물학회:학술대회논문집
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• 한국방사성폐기물학회 2016년도 추계학술논문요약집
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• pp.231-232
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• 2016

• 방사성폐기물학회지
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• 제20권4호
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• pp.429-453
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• 2022

Numerical modeling and scenario composition are needed to characterize the geological environment of the disposal site and analyze the long-term evolution of natural barriers. In this study, processes and features of the hydro-mechanical behavior of natural barriers were categorized and represented using the interrelation matrix proposed by SKB and Posiva. A hydro-mechanical coupled model was evaluated for analyzing stress field changes and fracture zone re-activation. The processes corresponding to long-term evolution and the hydro-mechanical mechanisms that may accompany critical processes were identified. Consequently, practical numerical methods could be considered for these geological engineering issues. A case study using a numerical method for the stability analysis of an underground disposal system was performed. Critical stress distribution regime problems were analyzed numerically by considering the strata's movement. Another case focused on the equivalent continuum domain composition under the upscaling process in fractured rocks. Numerical methods and case studies were reviewed, confirming that an appropriate and optimized modeling technique is essential for studying the stress state and geological history of the Korean Peninsula. Considering the environments of potential disposal sites in Korea, selecting the optimal application method that effectively simulates fractured rocks should be prioritized.

• 대한한의학방제학회지
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• 제19권1호
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• pp.183-194
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• 2011

Objectives : To estimate the shelf-life by long-term storage test of Pyungwi-san. Methods : Experiments were conducted to evaluate the stability such as the selected physicochemical, heavy metal, microbilogical experiment under an acceleration test and long-term storage test of Pyungwi-san in different storage under room temperature, refrigeration and freezing. Futhermore, HPLC analysis was performed for the determinations of glycyrrhizin in the Pyungwi-san on an Inertsil ODS-3 column(250 mm ${\times}$ 4.6 mm, 5 um) using solvent 35% acetonitrile include 0.05% phosphoric acid at 254 nm. The flow rate was 1.0 mL/min. Results : The significant change was not showed in pH, heavy metal, microbiological, identification test and quantitative analysis based on acceleration test and long-term storage test. Retention time of glycyrrhizin in HPLC chromatogram was about 16.065 min and calibration curve showed good linearity($R^2$ = 0.9999). The contents of glycyrrhizin in acceleration test and long-term storage test were 0.068~0.076 mg/mL and 0.066~0.077 mg/mL, respectively. Shelf-lifes of room temperature, refrigeration and freezing by long-term storage test were predicted 41, 24 and 34 months, respectively. Conclusions : The suggested shelf-life would be helpful on the storage and distribution of herbal medicine.

• 한국산학기술학회논문지
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• 제20권10호
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• pp.395-405
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• 2019

우리나라는 경제발전, 출산율 저하, 보건의료의 발달로 65세 이상 노인 인구의 비율이 2018년 14% 고령사회, 2026년 20% 초고령사회로 예상되어 빠른 인구구조의 변화를 겪고 있다. 고령화에 따라 치매, 중풍 등 일상생활이 어려운 노인들의 수는 날로 증가하고, 핵가족화, 여성의 사회참여 증가 등으로 장기요양이 필요한 노인들을 가정에서 돌보는 것이 어려워졌다. 이에 정부는 이러한 사회적 구조 및 노인문제를 해결하기 위해 장기요양대상 노인의 삶의 질 향상과 가족부양 부담의 완화 등을 목적으로 노인장기요양보험법을 제정하여 시행하고 있다. 따라서 본 연구는 시설의 민영화와 난립으로 서비스의 공적 책임과 시설의 질 제고에 대한 요청이 확산되고 있는 부분을 살펴보고자 한다. 이 밖에도 저임금 요양인력의 양산, 재원조달 방식에 관한 문제 등의 대비가 다각도로 부족한 부분을 도출하고자 하였다. 본 연구를 통하여 노인장기요양보험제도가 초고령화 사회를 대비하여 장기 지속적으로 유지 발전하기 위해서는 법 제도적 측면의 개선방안의 모색과 더불어 노인복지서비스가 신체적 건강 뿐만 아니라 노후 생활의 안정을 위한 정신적 심리적 조치를 강구하는 방안을 검토하고자 한다.

• 지역사회간호학회지
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• 제30권3호
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• pp.295-306
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• 2019

Purpose: There has been a growing recognition that person-centered care enhances the quality of life of nursing home residents with dementia. This study was conducted to develop a person-centered dementia care online education program for direct care staff in long-term care facilities. Methods: Delphi method with expert group was used to validate contents. We developed 61 draft items based on literature review. Twenty experts participated in consecutive three round surveys including 5-point Likert scale questions and open-ended questions. Based on experts' opinions, the content validity ratio for content validity and the coefficient of variation for stability were calculated. Results: Three-round Delphi surveys and additional feedback from the expert panel established a consensus of core contents: 1) dementia (7 categories), 2) person-centered care (6 categories), 3) communication (8 categories), and 4) behavioral and psychological symptoms of dementia (6 categories). Specific sub-categories in each category were differentiated according to the job qualifications (65 sub-categories for registered nurses, 64 sub-categories for nursing aids, and 41 sub-categories for personal care workers). Conclusion: This delphi study identified person-centered dementia education curricula, in which the person-centered approach should be a key policy priority in Korean long-term care system. Now it is urgently needed to develop education programs utilizing online platforms that enable efficient and continuous learning for long-term care staff, which can contribute to behavior changes in the person-centered dementia care approach and improvement of care quality in long-term care facilities.