• Structural Monitoring and Maintenance
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• 제5권3호
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• pp.325-343
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• 2018

This study aims to propose a performance-based design method of a novel passive base isolation system, BIO isolation system, which is inspired by an energy dissipation mechanism called 'sacrificial bonds and hidden length'. Fragility functions utilized in this study are derived, indicating the probability that a component, element, or system will be damaged as a function of a single predictive demand parameter. Based on PEER framework methodology for Performance-Based Earthquake Engineering (PBEE), a systematic design procedure using performance and fragility objectives is presented. Base displacement, superstructure absolute acceleration and story drift ratio are selected as engineering demand parameters. The new design method is then performed on a general two degree-of-freedom (2DOF) structure model and the optimal design under different seismic intensities is obtained through numerical analysis. Seismic performances of the biologically inspired (BIO) isolation system are compared with that of the linear isolation system. To further demonstrate the feasibility and effectiveness of this method, the BIO isolation system of a 4-storey reinforced concrete building is designed and investigated. The newly designed BIO isolators effectively decrease the superstructure responses and base displacement under selected earthquake excitations, showing good seismic performance.

• 한국생활과학회지
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• 제17권5호
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• pp.963-973
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• 2008

Clothing pressure is closely connected with the degree of comfort of an athlete's tight-fitting garments. Therefore, the construction of sports garments is very important to the wearer's athletic performance. In this study, the fundamental relationship between the reduction rates of stretch fabrics and clothing pressure was explored with the aim of improving clothing comfort and obtaining a systematic pattern reduction for women's tight-fitting bodysuits. A women's bodysuit pattern was obtained by the draping method using a dressform. The basic pattern was divided into four parts and changed into reduced pattems according to the amount of fabric stretch determined by ASTM D2594. Clothing pressure was measured using an air-pack-type pressure sensor (model AMI 3037-2) at 20 locations (shoulder, 9 locations; bust, 5; and armhole, 6). Among the 15 garments tested, the mean pressure of the A1 bodysuit was 4.60 $gf/cm^2$, and that of the C5 bodysuit was 22.98 $gf/cm^2$. The mean pressures of the bodysuits with reduction rates of 10% and 20% were below 10 $gf/cm^2$, while those of suits with reduction rates of 30%,40%, and 50% (except C5) were below 20 $gf/cm^2$. The pressure at the shoulder was 9.50$\sim$32.24 $gf/cm^2$, which was higher than that at the bust (3.34$\sim$24.56 $gf/cm^2$) and the armhole (0.95$\sim$12.15 $gf/cm^2$). The mean pressures of the 15 bodysuits were divided into five groups using analysis of variance (ANOVA), and were found to be significantly different (p<0.001). Regression analysis afforded the following expression: mean pressure ($gf/cm^2$) = 1.607 + 0.369[reduction rate (%)].

• 디지털융복합연구
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• 제18권2호
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• pp.323-331
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• 2020

본 연구의 목적은 욕창에 대한 예방적 중재방법과 영향요인을 비교, 분석하기 위해 기존문헌을 체계적으로 고찰하였으며 논문은 PRISMA(Preferred reporting items for systematic reviews) 지침에 따라 자료를 수집하고 분석하였다. 문헌은 2010년부터 2019년 6월까지 국내외에서 발표된 논문을 대상으로 하였다. 본 연구의 논문 선정기준에 따라 총 30의 논문이 선택되었으며 실험연구가 8편, 코호트 연구가 3편, 단면조사연구가 19편 이었다. 논문검색어는 국내논문의 경우 욕창, 압박욕창, 압박궤양, 예방, 중재의 단어를 조합하여 검색하였다. 분석결과 욕창의 예방적 중재와 예측요인을 통합적으로 제시하였으며 특히 체위변경과 압력 감소 장치 적용한 중재는 욕창 발생률을 감소시켰으며 욕창 발생 감소와 욕창예방에 중요한 중재임이 확인되었다. 본 연구결과를 토대로 각 의료기관에 적합한 욕창의 예방적 중재를 위한 기초 자료를 제공하고자 한다.

• 여성건강간호학회지
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• 제13권4호
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• pp.320-326
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• 2007

Purpose: This study was carried out in an attempt to find weight control behaviors (BMI, experiences of weight control, weight control related factors, etc.) of college female students. Method: The subjects were 596 female students in 104 universities and colleges in Korea. Data was collected by using a questionnaire developed through a pretest. Result: Seventy five percent of subjects were in the normal range in weight, but 63.8% have experienced weight control behaviors and 58.9% have worried about their weight. Middle and high school was the first time to have concerns about their weight/body image. In addition, the influence towards weight control was mainly by mass communication. Weight control frequency in the most recent most year correlated with concern about weight, first time of weight control, maximum maintaining period of losing weight and BMI. Conclusion: To ensure resonable body image and weight control behaviors in women, education has to begin in elementary schools. In the case of weight control, scientific and systematic weight reduction programs should be developed.

• 한국정밀공학회지
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• 제26권5호
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• pp.57-63
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• 2009

Interface friction in blanking dies, cold forging and extrusion of aluminum alloys is a major cause of inefficient process. This paper describes an investigation of femtosecond laser texturing for reduction of interface friction on sliding surfaces in forming process. Femtosecond direct writing technology was used to fabricate a laser micro-machined die and to create microgroove patterns with varying size and density on metal forming dies. A systematic approach to find the optimum parameters and computer simulation comparison of friction coefficients are provided to study the relation of friction coefficients and die profiles. In metal forming tests, the effectiveness of various laser-machined patterns for enhancing interface lubrication is determined.

• Bulletin of the Korean Chemical Society
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• 제30권7호
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• pp.1588-1592
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• 2009

Lithium cyanoaluminum hydride (LCAH) was prepared by the metal cation exchange reaction of sodium cyanoaluminum hydride with lithium chloride in tetrahydrofuran. The reducing characteristics of LCAH were explored systematically by the reaction with selected organic compounds containing representative functional groups under the standardized conditions (tetrahydrofuran, 0 ${^{\circ}C}$). The reducing ability of LCAH was also compared with of the sodium derivative, sodium cyanoaluminum hydride (SCAH). Generally, the reducing behavior of LCAH resembles that of SCAH closely, but the reactivity of LCAH toward representative organic functional groups appeared to be stronger than that of SCAH. Thus, the regent reduces carbonyl compounds, epoxides, amides, nitriles, disulfides, carboxylic acids and their acyl derivatives to the corresponding alcohols or amines, at a relatively faster rate than that of SCAH. The cyano substitution, a strong election-withdrawing group, diminishes the reducing power of the parent metal aluminum hydrides and hence effects the alteration of their reducing characteristics.

• Bulletin of the Korean Chemical Society
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• 제13권6호
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• pp.670-676
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• 1992

A systematic study of the partial reduction of carboxylic acids and their derivatives to the corresponding aldehydes with lithium tris(dialkylamino)aluminum hydrides under practical conditions has been carried out. The diethylaminosubstituted derivative of lithium aluminum hydride, lithium tris(diethylamino)aluminum hydride (LTDEA), shows quite general applicability in the conversion of carboxylic acids, carboxylic esters, and primary carboxamides to the corresponding aldehydes. Lithium tripiperidinoaluminum hydride (LTPDA) also appears to be a reagent of choice for such partial transformation of primary carboxamides. In additioin, both LTDEA and LTPDA reduce tertiary carboxyamides to aldehydes in high yields. Finally, lithium tris(dihexylamino)aluminum hydride (LTDHA) is capable of achieving the chemoselective reduction of aromatic nitriles to aldehydes in the presence of aliphatic nitriles under practical conditions.

• 한국산학기술학회논문지
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• 제18권6호
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• pp.438-448
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• 2017

본 연구는 요도 카테터 삽입술에서의 리도카인 윤활제의 통증 감소 효과를 검증하기 위해 수행된 체계적 문헌고찰 및 메타분석연구이다. 문헌검색은 PRISMA 가이드라인에 의거하여 데이터베이스 7개(MEDLINE, Cochrane Central, CINAHL, RISS, Koreamed, KISS, NDSL)와 회색문헌을 통해 수행되었다. 비뚤림 위험은 Risk of Bias(RoB) 도구를 통해 평가되었으며 자료의 분석은 RevMan 5.3 프로그램을 이용하였다. 문헌의 선택배제기준에 따라 합계 성인 대상자 1904명이 포함된 16편의 문헌이 최종 선정되었으며 funnel plot에서 비뚤림 위험이 관찰되지 않았다. 리도카인 윤활제의 통증 점수는 대조군과 비교할 때 표준화된 평균차이가 SMD -0.96(95% CI: -1.43, -0.49)로, 전반적으로 유의한 통증 감소효과를 보였다(p<.001). 이질성(($I^2=95%$, p<.001)의 원인을 탐색하기 위해 카테터 종류(도뇨카테터, 경성 및 연성방광경 카테터)에 따라 하위집단 분석을 실시하였으며 표준화된 평균차이가 각각 SMD -0.88(95% CI:-1.51, -0.26), -0.31(95% CI:-0.63, 0.01), -1.93(95% CI:-2.88, -0.97)이었다. 도뇨카테터 삽입에서는 성별에 관계없이 통증 감소 효과가 있었으나 경성방광경 카테터에서는 남성에서만 유의한 통증 감소 효과가 있었다. 용량에 있어 경성 방광경 카테터에서는 리도카인 윤활제를 10-11ml 이상을 사용한 경우 통증 감소 효과가 관찰되었다. 도뇨카테터에서는 리도카인 윤활제를 도포하는 방법만으로도 시간에 관계없이 유의한 통증 감소 효과가 있었다. 본 연구 결과 리도카인 젤은 남성의 요도 내로 경성방광경 카테터를 삽입하는 경우, 남녀 모두에게 도뇨카테터 삽입을 하는 경우에 유용한 통증 감소용 윤활제로 확인되었다.

• Clinical Nutrition Research
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• 제11권3호
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• pp.214-227
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• 2022

Despite controversies, no earlier study has systematically summarized findings from earlier studies on the effect of artichoke supplementation on blood pressure. Therefore, current systematic review and meta-analysis was done on the effect of artichoke supplementation on systolic blood pressure (SBP) and diastolic blood pressure (DBP) in adults. Five databases were searched from inception to January 2022 using relevant keywords. All randomized clinical trials investigating the impact of oral artichoke supplementation on any of the blood pressure parameters including SBP or/and DBP were included. Out of 1,507 citations, 7 trials that enrolled 472 subjects were included. Artichoke supplementation resulted in significant reduction in SBP (weighted mean difference [WMD], -2.01 mmHg; 95% confidence interval [CI], -3.78, -0.24; p = 0.026) and DBP (WMD, -1.45 mmHg; 95% CI, -2.81, -0.08; p = 0.038). Greater effects on SBP were detected in trials using ≤ 500 mg artichoke, lasted > 8 weeks, participants aged < 50 years' old and sample size ≤ 70. There was also a similar impact of artichoke on DBP. However, significant non-linear associations were found between artichoke supplementation dosage and study duration with both SBP (for dosage: p_{non-linearity} = 0.002, for duration: p_{non-linearity} = 0.016) and DBP (for dosage: p_{non-linearity} = 0.005, for duration: p_{non-linearity} = 0.003). We found a significant reduction in both SBP and DBP following artichoke supplementation in adults. It could be proposed as a hypotensive supplement in hypertension management.

• 한국식품영양학회지
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• 제19권3호
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• pp.332-341
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• 2006

The goal of this study was to determine a method of reducing food wastes in the dietary home lifestyle. Statistical analyses were conducted of 491 questionnaires answered by housekeepers living in Daejeon city. The data were analyzed by SAS program and the results are summarized as follows. Among the respondents, 51.53% answered that they purchased the foods in consideration of the family number, 60.45% that they occasionally throw away foods because the date of expiry had passed, i.e., the foods threw away by mistake of storage, 68.23% that they make side dishes at a time for three meals in a day, 52.95% that they make three or four kinds of side dishes, 82.28% that they prepared meals according to the favorite foods of the family, 48.04% that they left food at home, and 47.32% that they threw away foods because too many foods had been prepared. The major reasons for food wastes at home were listed as meal leftovers (32.72%), vegetable trimming (31.29%), and non-planned purchase (25.77 %). The perception of housekeepers on the reduction of food waste were listed as the preparation of accurate meal quantity (50.92%), planned purchase (28.31%), development of recycling foods (14.05%), and reduction of side dishes (6.72%). Further reduction of food wastes of dietary home lifestyle can be summarized to emphasize the preparation of accurate meal quantity, planned purchase, development of recycling foods, and reduction of side dishes. In addition, studies should be conducted to examine the systematic administration method and standard education for the reduction of food wastes.