• Clinics in Shoulder and Elbow
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• 제9권1호
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• pp.68-72
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• 2006

Purpose: To demonstrate arthroscopically the presence of bilateral shoulder "mirror lesions" due to overhead work. Materials and Methods: A cross-sectional study was performed in a historical cohort of 10 male tire plant workers who underwent MRI studies of both shoulders. Bilateral intraarticular shoulder pathology was diagnosed by magnetic resonance imaging and confirmed by arthroscopy. "Mirror lesions" were defined as similar pathology between an individual patient's two shoulders. Results: We report on ten patients who had bilateral "mirror lesions." The most common mirror lesions were tears of the rotator cuff. Most patients (7 of 10) had more than one mirror lesion in their shoulders. There were two bilateral full thickness tears involving the supraspinatus and infraspinatus, four bilateral partial thickness supraspinatus tears, six bilateral partial or upper corner lesion complete subscapularis tears, and one bilateral complete supraspinatus tear. Conclusion: Occupational overhead work with simultaneous use of both arms is associated with bilateral shoulder lesions verified by arthroscopy. By demonstrating the work-related bilateral shoulder involvement, this study suggests an etiopathogenesis for these lesions and provides rational for developing worksite prevention strategies.

• 한국기계가공학회지
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• 제17권1호
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• pp.1-7
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• 2018

We aimed to develop a high quality 3.5 ton class swing reducer by studying the efficiency improvement of the reducer through the optimum design and performance evaluation of the assembled, high efficiency, lightweight 3.5 ton swing reducer. Based on the optimal design of the worm and worm wheel, the optimal manufacturing method of the worm wheel, the optimized casing design, and the optimum design of the output pinion, Respectively. Therefore, in this paper, to improve the efficiency of the worm gear reducer system, we will develop the manufacturing technology and verify the mass production by combining the manufacturing process design, processing and assembling technology according to the optimization design. We have conducted research to realize mass production by product verification such as product efficiency, reliability and durability according to optimal design of worm gear reducer.

• 한국시뮬레이션학회논문지
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• 제23권2호
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• pp.47-55
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• 2014

한국군의 분석용 시뮬레이션모델을 포함한 대개의 전투시뮬레이션 모델들은 통합화력과 같은 복잡한 전투상황을 모델링, 분석하기에는 어려움이 많다. 본 연구에서는 Fire Eagle과 같은 지상화력과 육군항공의 통합화력전투훈련의 분석을 위한 모델링 및 시뮬레이션 요구사항을 분석한다. 이에 기반하여 Fire Eagle을 위한 시뮬레이션 모델을 제안, 개발하고 통합화력을 개선하기 위한 전략을 도출한다. 이 시뮬레이션 모델을 이용하여 특정 작전계획 및 시나리오의 효과성을 분석한다. 이 시뮬레이션 실험 결과를 바탕으로 효율적이고 효과적인 작전계획을 개발하는 시범을 보인다.

• Journal of Ginseng Research
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• 제33권4호
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• pp.337-342
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• 2009

The extraction conditions for the production of red ginseng polysaccharide were proposed. The crude fiber content of red ginseng marc (RGM) (15.3%) was much higher than that of white ginseng (WG) (2.1%) and red ginseng (RG) (0.5%). Thus, RGM was selected as the raw material for polysaccharide production. The correlation between the particle size of RGM and the polysaccharide extraction was investigated with a correlation analysis using the SPSS package. The two parameters were found to have a significant correlation (p<0.01). The polysaccharide extraction increased as the particle size of RGM decreased. The optimal concentration of RGM was 6.66% (w/v). The extraction yield increased as both the extraction temperature and the extraction time increased. Finally, the extraction temperature and time were selected as $85^{\circ}C$ and 5 hrs, respectively. Consequently, the extraction conditions for polysaccharide production were optimized and statistically confirmed.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2007년도 정기 학술대회 논문집
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• pp.277-282
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• 2007

In recent years, dramatic advances in information technology have motivated the construction industry to improve its productivity. Most construction companies are trying to utilize some new information technologies for enhancing the structure quality, shortening construction time, and reducing the construction cost. Digital Mock-Up (DMU) technology utilizes 3D CAD/CAM system that shows the shape of a structure on the computer screen. By modeling and assembling the structure in 3D dimensional environments, some errors in design can be found before or during construction. In this paper, DMU technology was applied to the detail design and construction of In-Cheon Bridge and its effectiveness was evaluated. All components of a PSC box girder segment were modeled and assembled by using of 3D CAD tools and then, some interferences between components and errors were found and revised appropriately before construction. Consequently, DMU technology would improve the quality of the structure and reduce time and cost for construction.

• 한국물환경학회지
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• 제30권2호
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• pp.184-198
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• 2014

For estimating discharge and pollution loads into the Yeongsan lake, a conceptual watershed model HSPF(Hydrological Simulation Program - Fortran) was applied to the Yeongsan River Basin. Various spatial data set including DEM, watershed boundaries and land uses were used to set up the model for the Yeongsan River Basin that was divided into 45 sub-basins. The model was calibrated and validated for the river discharges, SS, BOD, TN and TP concentrations against the data observed in 2011 at several monitoring stations. The simulation results show good agreement with the observed water flows($R^2$ = 0.46 - 0.97, NSE = 0.70 - 0.96). The simulated concentrations of SS, BOD, TN and TP are also in good agreement with the observed. The total freshwater discharge to the Yeongsan lake is estimated $2,406{\times}10^6m^3/year$ which the Jiseok and Hwangryoung stream contribute as much as 19%, 17% respectively. It is estimated that the total discharges to the Youngsan lake is SS 152,327 ton/year, BOD 15,721 ton/year, TN 10,071 ton/year, TP 563 ton/year. Both water and pollution loads are high in summer, particularly in July, when the monsoon season arrives at the Korean peninsula.

• 펄프종이기술
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• 제37권1호
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• pp.1-9
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• 2005

Many factors which affect the adsorption of cationic polymers on fibers and fines have been investigated by many researchers that include contact time, pH, collision frequency, properties of cationic polymers and adsorbent, etc. But the effect of white water quality on the adsorption of cationic polymer have not been examined throughly. In this study, the adsorption of cationic PAM was analyzed as a function of white water quality. The adsorption of the cationic PAM was analyzed by two analysis methods, Kjeldahl nitrogen content measurement and electrokinetic measurements. When the distilled water was used, adsorbed amount of C-PAM and zeta-potential of fibers increased as a function of the addition of C-PAM. When closure level increased, nitrogen content of fibers increased indicating that the cationic PAM was adsorbed. Zeta-potential of fibers, however, showed no significant change with the increased addition of C-PAM. This showed that adsorption of C-PAM was not reflected by zeta-potential of fibers due to the deteriorated efficiency of C-PAM by the anionic contaminants in white water.

• 한국콘텐츠학회논문지
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• 제3권1호
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• pp.9-13
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• 2003

이 논문에서는 비디오 영상에서의 블록 모션 측정을 위한 통계학적인 특징에 기반 한 알고리즘을 제안한다. 우선 참조 블록의 통계학적인 특징을 구하고, 이를 참조 블록의 통계적 특징과 정규 시작점 패턴 (SPP) 에 퍼져 있는 블록에서의 특징을 비교하여, SPP에서의 시작점 (SP) 후보를 선택하는 데에 적용한다. 최종적인 SP 들은 SP 후보 들에서의 평균절대차이 (MAD) 값으로 구한다. 마지막으로 기존의 고속탐색 알고리즘인 BBG나 DS 그리고 TSS중 하나를 이용하여 참조블록의 모션 벡터를 최종 SP를 시작점으로 하여 계산하였다. 실험결과는 기대 했던 바와 같이 최종 SP로부터의 시작점들이 전역최소값 (global minimum)에 근접함을 보여 주었다.

• 한국전자파학회논문지
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• 제23권11호
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• pp.1323-1326
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• 2012

군사적 목적으로 많은 레이다들이 근거리에서 동시에 운용된다. 특히, 동종의 레이다가 동시에 운용될 경우 주파수 할당을 해야 한다. 많은 레이다가 동시에 운용될 때 일부 주파수를 공유하여야 하는데, 부득이하게 레이다 시스템 간 간섭이 발생하게 된다. 레이다간 간섭은 성능을 저하시킬 수 있기 때문에, 간섭 신호의 억제는 중요한 문제이다. 본 논문에서는 두 대의 FMCW 레이다간 간섭 신호를 분석하고, 간섭 신호를 이용하여 레이다간 시간 동기화 방법을 제안하였다. 실제 레이다 시스템을 통해 제안된 방법의 성능을 검증하였다.

• 간호행정학회지
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• 제21권5호
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• pp.552-560
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• 2015

Purpose: This study was performed to identify the mediating effect of empowerment in the relationship between head nurses' servant leadership and organizational commitment among clinical nurses. Methods: A cross-sectional survey design was used. A convenience sample of 249 nurses was recruited from three hospitals located in J province, South Korea. Data were collected by self-report questionnaires, including general characteristics, servant leadership, empowerment, and organizational commitment. Data were analyzed with descriptive statistics, Pearson correlation coefficients, independent t-test, One-way ANOVA, and linear regression using the SPSS 22.0 program. Results: Head nurses' servant leadership perceived by clinical nurses significantly influenced their organization commitment. Empowerment partly mediated the effect of servant leadership on organizational commitment. Conclusion: The findings suggest the importance of improving nurse managers' servant leadership and empowering nurses to increase their organizational commitment.