• 국제강구조저널
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• 제18권4호
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• pp.1191-1199
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• 2018

Concepts of submerged floating tunnels (SFTs) for land connection have been continuously suggested and developed by several researchers and institutes. To maintain their predefined positions under various dynamic environmental loading conditions, the submerged floating tunnels should be effectively moored by reasonable mooring systems. With rational mooring systems, the design of SFTs should be confirmed to satisfy the structural safety, fatigue, and operability design criteria related to tunnel motion, internal forces, structural stresses, and the fatigue life of the main structural members. This paper presents a feasibility study of a submerged floating tunnel moored by an inclined tendon system. The basic structural concept was developed based on the concept of conventional cable-stayed bridges to minimize the seabed excavation, penetration, and anchoring work by applying tower-inclined tendon systems instead of conventional tendons with individual seabed anchors. To evaluate the structural performance of the new type of SFT, a hydrodynamic analysis was performed in the time domain using the commercial nonlinear finite element code ABAQUS-AQUA. For the main dynamic environmental loading condition, an irregular wave load was examined. A JONSWAP wave spectrum was used to generate a time-series wave-induced hydrodynamic load considering the specific significant wave height and peak period for predetermined wave conditions. By performing a time-domain hydrodynamic analysis on the submerged floating structure under irregular waves, the motional characteristics, structural stresses, and fatigue damage of the floating tunnel and mooring members were analyzed to evaluate the structural safety and fatigue performance. According to the analytical study, the suggested conceptual model for SFTs shows very good hydrodynamic structural performance. It can be concluded that the concept can be considered as a reasonable structural type of SFT.

• 임상간호연구
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• 제29권3호
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• pp.296-311
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• 2023

Purpose: This study aimed to identify factors related to the workload of intensive care unit nurses through a systematic literature review and meta-analysis to provide basic data to explore the direction of development of nursing staffing standards. Methods: This study involved quantitative studies about nurses working in intensive care units related to nursing workload published in English or Korean since 2000. Search terms included 'intensive care unit', 'nursing workload', and their variations. Databases such as RISS, DBpia, MEDLINE(PubMed), CINAHL, PsycINFO, and Web of Science were utilized. Quality assessment was conducted using the Joanna Briggs Institute's Critical Appraisal Checklist for Analytical Cross-Sectional Studies. JAMOVI software facilitated the analysis of effect sizes, employing a meta-analysis approach for 7 studies with correlational or regression data. Results: From 16 studies on the workload of intensive care unit nurses, a total of 20 patient and nurse-related factors were identified. Patient-related factors included severity of illness, length of stay, and age. Meta-analysis was conducted for three patient-related factors: age, severity of illness measured by SAPS 3, and length of stay. Only severity of illness measured by SAPS 3 was significantly associated with nurse workload (Zr=0.16, p<.001, 95% CI=0.09-0.24). Conclusion: In previous studies, the characteristics of intensive care units and patients varied across studies, and a variety of scales for measuring workload and severity of illness were also used. Sustained research reflecting domestic intensive care unit work environments and assessing the workload of intensive care unit nurses should be imperative.

• 한국식품영양과학회지
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• 제39권11호
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• pp.1705-1709
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• 2010

본 연구에서는 130여종의 육성계통 고추의 capsaicinoids와 ascorbic acid 등의 기능성 성분의 함량을 분석함으로써 부가가치 높은 우수 고추 품종 개발을 위한 database를 제공하고자 하였다. Capsaicinoids 및 ascorbic acid 분석을 위해 역상 HPLC를 이용하였다. 연구 결과 capsaicin의 평균함량은 29.0 mg/100 g, dihydrocapsaicin은 15.8 mg/100 g으로 나타났으며 ascorbic acid의 평균 함량은 809.8 mg/100 g이었다. 육성계통 고추 No.2687의 capsaicin 함량은 219.6 mg/100 g, dihydrocapsaicin 함량은 110.8 mg/100 g으로 가장 높게 분석되었으나 ascorbic acid 함량은 264.9 mg/100 g으로 가장 낮게 분석되었다. 또한 육성계통 고추 No. 2524가 ascorbic acid의 함량이 1695.5 mg/100 g으로 가장 높았으나 capsaicinoid 함량은 평균 이하로 낮게 나타났다. 분석방법을 검증하기 위해 재현성, 반복성 및 회수율을 구하였으며 그 결과 재현성과 반복성의 CV는 5% 이하였으며 회수율은 90% 이상으로 우수하였다. 본 연구 결과는 고추의 육성 계통별 기능성 성분의 함량을 분석하고 그 결과를 토대로 우수품종 개발을 위한 기초자료를 제공함에 그 의의가 있다.

• 한국식품영양과학회지
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• 제44권7호
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• pp.1035-1040
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• 2015

껍질을 제거하지 않은 새우의 경우 10일 동안 저장하는 과정에서 갈변이 심각하게 진행된 것을 확인할 수 있었다. 갈변은 두흉부, 등껍질 그리고 꼬리 순서로 진행되었으며, 4-hexylresorcinol 침지액에 의해 갈변이 억제될 경우 꼬리, 등껍질 그리고 두흉부 순서로 억제되었다. 껍질을 제거하지 않은 새우의 경우 10, 20 mg/L 4-hexylresorcinol 침지액 농도에서 72시간 침지한 새우로부터 각각 1.36, 2.33 mg/kg의 잔류농도를 확인하였으며, 해외에서 규정하고 있는 최대잔류수준 이상의 4-hexylresorcinol이 검출되어 갈변억제 효과는 있었지만 사용방법으로 부적합한 것으로 나타났다. 껍질을 제거한 새우의 경우에는 가식부위가 직접 침지액에 침지되기 때문에 대부분의 새우에서 1 mg/kg 이상의 4-hexylresorcinol 잔류량이 확인되었으며, 껍질을 제거한 새우를 20 mg/L 4-hexylresorcinol 침지액에 72시간 동안 침지한 처리군에서 13.46 mg/kg으로 가장 높은 4-hexylresorcinol 잔류량이 확인되었다. 이러한 결과는 캐나다 및 중국뿐만 아니라 유럽에서 규정하고 있는 최대잔류수준을 초과함에 따라서 새우의 침지 조건으로 새우 껍질을 제거한 뒤 침지하는 방법은 적합하지 않은 것으로 판단되며, 갈변억제 효과는 20 mg/L 4-hexylresorcinol 침지액에서 24시간 동안 침지한 처리군에서 가장 높은 억제 효과를 나타내었다. 본 연구 결과 4-hexylresorcinol 침지액 농도와 침지 시간에 따라 4-hexylresorcinol 잔류량 및 갈변억제 효과에 높은 상관관계를 나타내었으며, 규정에 제시되어 있는 최대잔류허용량을 초과하지 않고 효율적인 갈변억제 효과를 얻기 위한 방법으로는 껍질을 제거하지 않은 새우에서 20 mg/L 4-hexylresorcinol 침지액에서 24시간 동안 침지처리하는 방법이 가장 적절한 것으로 확인되었다.

• 한국간호교육학회지
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• 제19권1호
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• pp.24-32
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• 2013

Purpose: The purpose of this study was to analysis the research trends of pediatric nursing intervention studies in Korea form 2000 to 2011. Methods: A literature search was conducted from the databases. RISS and 'Infant', 'Toddler', 'Preschooler', 'Schooler', 'Adolescent', 'Child', 'Effect', 'Program', 'Intervention' and 'Nursing' were used for keyword searches to find relevant studies. A total of 37 published articles and dissertations in Korea from 2000 to 2011 were reviewed using a structured analytical frame. Results: A quasi-experimental design was more common at 91.9% with a true experimental design at 2.7%. The portion of studies in which theoretical framework was suggested was 27.0%. Only 8.1% mentioned International Review Board (IRB) approval and 78.4% received only the participant's agreement. The participants' developmental stage was mostly preschool stage, and 37.0% of the child's health problem was a chronic disease. Sensory interventions made up 45.9% of the types of intervention and most of the sensory interventions were distraction interventions. The contents of intervention outcomes were physiological (54.0%) and psychological (28.0%) categories mostly. Conclusion: This study will help in identifying current research trends of pediatric nursing intervention studies in Korea and provide basic data for the direction of developing pediatric nursing interventions.

• 한국자기학회지
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• 제24권5호
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• pp.146-151
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• 2014

영구자석과 홀소자로 구비된 집게형 맥진기를 이용하여 목 부위의 경추동맥의 맥진파형과 손목 부위의 요골동맥 맥진파형을 각각 측정하였다. 두 개의 맥진파형을 비교하여 얻은 맥파전달시간과 맥파전달속도를 분석하였다. 맥파전달속도는 기존의 방식으로 측정한 값과 유사한 약 8.5 m/s으로 나타났다. 재현성과 신뢰성이 있는 한방의료기기인 집게형 맥진기로 얻은 맥파전달속도를 기준하여 동맥경화도를 예측할 수 있음을 제시하였다.

• 한국환경과학회지
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• 제20권11호
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• pp.1499-1507
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• 2011

Practical disposal of transformer insulation oil laden with PCBs (polychlorinated biphenyls) by a chemical treatment has been studied in field work. The transformer insulation oil containing PCBs was treated by the required amounts of PEG (polyethylene glycol) and KOH, along with different reaction conditions such as temperatures and times. The reaction of PEG with PCBs under basic condition produces arylpolyglycols, the products of nucleophilic aromatic substitution. Removal efficiencies of PCBs in insulation oil before and after chemical treatment were examined. The removal efficiency of PCBs was very low at lower temperatures of 25 and $50^{\circ}C$. Under the reaction condition of PEG 600/KOH/$100^{\circ}C$/2hr, removal efficiency of PCBs was approximately 70%, showing completely removal of PCBs containing 7~9 chlorines on biphenyl frame which appear later than PCB IUPAC Number 183 (2,2',3,4,4',5',6-heptaCB) in retention time of GC/ECD. However, when increasing the reaction temperature and time to $150^{\circ}C$ and 4 hours, removal efficiency of PCBs reached 99.99% without any formation of PCDDS/PCDFs during the process. Such reaction conditions were verified by several official analytical institutions. In studying the reaction of PEG with PCBs, it confirmed that the process of chemical treatment led to less chlorinated PCBs through a stepwise process with the successive elimination of chlorines.

• 한국대기환경학회지
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• 제21권6호
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• pp.639-647
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• 2005

A single particle analytical technique, named low-Z particle electron probe X-ray microanalysis (EPMA), was applied to characterize samples collected at a subway station and ambient samples in Seoul. According to their chemical composition, many distinctive particle types were identified. For samples collected at the subway station platform, the major chemical species are carbon-rich, organic, aluminosilicates (AlSi), AlSi/C, AlSi/$CaCO_{3},\;CaCO_{3},\;SiO_{2},\;and\;Fe_{2}O_{3}$. For outdoor samples, carbon-rich, organic, AlSi, $CaCO_{3},\;SiO_{2},\;NaNO_{3},\;(Na,Mg)NO_{3},\;Na(CO_{3},NO_{3},SO_{4}),\;and\;(NH_{4})_2SO_4$, are abundantly encountered. Samples collected at the subway station show very high contents of $Fe_{2}O_{3}$, both in coarse and fine fractions, which come from brake block, subway train wheel, electric contact materials, etc. It is demonstrated that the single-particle characterization using this low-Z particle EPMA technique provided detailed information on various types of chemical species in indoor and outdoor samples.

• 한국기계가공학회지
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• 제18권1호
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• pp.9-15
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• 2019

This study focused on the application of ELID mirror-surface grinding technology to the manufacture of off-axis asymmetric large-area reflecting mirrors made of BK7 glass. The size of the parts, such as asymmetric large-area mirrors or lens, made form-accuracy or roughness especially hard to measure after machining because of the measuring range limit of measurement devices. In this study, the ELID grinding system has been set up for mirror-surface machining experiments manufacturing off-axis asymmetric lenses. A measuring method using a reference workpiece has been suggested to measure the form-accuracy and roughness. According to the experimental results, even when using only a reference workpiece, it is confirmed that the surface roughness was 8 nmRa and form-accuracy was 80 nmRMS, with a best fit asymmetric radius when using a grinding wheel of #8,000. It is found that the accuracy of large-area parts could be estimated by the proposed process.

• 디지털융복합연구
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• 제12권4호
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• pp.485-493
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• 2014

본 연구는 통계적 방법의 올바른 사용을 통해 의류학 분야 연구결과의 과학성과 윤리성을 높이는데 도움을 주고자 실시되었으며, 나아가 본 연구가 통계적 방법을 활용하는 의류학 관련 연구 발전에 기여하는데 의의가 있다. 연구 결과는 다음과 같다. 첫째, 통계적 방법의 적용이나 통계패키지의 활용과정에서 나타나는 오류는 의류학 관련 연구에서도 예외는 아니었다. 이에 본 연구에서는 한국의류학회지를 대상으로 연구과정에서 자주 발생할 수 있는 통계적 오류에 대해서 알아보았으며, 그 결과 각 단계별로 많은 오류가 있음을 확인하였다. 둘째, 요인분석 등에 있어 올바른 분석방법을 적용하고 있지도 않을 뿐더러, 천편일률적으로 기계적인 기술을 하고 있었다. 또한 교차분석의 경우에도 가설설정이 없으며, 검정의 내용을 혼동하는 경우가 많았다.