• Structural Monitoring and Maintenance
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• v.5 no.3
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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.

• Korean Journal of Human Ecology
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• v.17 no.5
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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 (%)].

• Journal of Digital Convergence
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• v.18 no.2
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• pp.323-331
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• 2020

This study was to perform a systematic review to examine pressure ulcer preventive intervention and risk factors. PRISMA flow diagram in accordance with the selection process of this research was done. The literatures were retrieved from domestic and international study from 2010 to June, 2019. A total of 30 literatures were selected according to the selection criteria of this study. The literatures were searched electronically using the search engine with the key words of 'pressure ulcers', 'bedsore', 'decubitus ulcers', 'intervention', 'prevention'. The results of this study suggest that mediation with position change and pressure reduction device reduced the incidence of pressure sores and was important for prevention. Based on the results of this study, we provide basic data for preventive intervention of pressure ulcers that are appropriate for each medical institution.

• Women's Health Nursing
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• v.13 no.4
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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.

• Journal of the Korean Society for Precision Engineering
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• v.26 no.5
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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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• v.30 no.7
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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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• v.13 no.6
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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.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.6
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• pp.438-448
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• 2017

This study was a systematic review and meta-analysis that evaluated the results of research on the pain reduction effects of lidocaine gel for urethral catheterization in adults. A literature search was conducted using seven electronic databases, gray literature and other resources based on the guidelines of Preferred Reporting Items for Systematic review and Meta-Analysis (PRISMA). A Risk of Bias (RoB) tool was applied to assess the quality of selected studies. Data were analyzed using the RevMan 5.3.-program. Sixteen randomized controlled trials involving 1904 adults were included. RoB was not observed in the funnel plot. Overall, lidocaine gel was effective for pain reduction during urethral catheterization (Standard Mean Difference[SMD] -0.96;95% CI: -1.43, -0.49). To explore the cause of heterogeneity (I2=95%, p<.001), subgroup analysis was conducted according to three catheter types (urinary catheter, flexible cystoscopy, and rigid cystoscopy) and the SMDs were -0.88 (95% CI:-1.51, -0.26), -0.31 (95% CI:-0.63, 0.01), and -1.93 (95% CI:-2.88, -0.97), respectively. A significant pain reduction effect was observed regardless of gender in urinary catheterization. However, in rigid cystoscopy, a significant pain reduction effect was observed only in male subjects. Pain reduction effects were observed when 10~11ml lidocaine gel was used during rigid cystoscopy and when lubrication was used during urinary catheterization, irrespective of application time. These findings suggest that lidocaine gel is a useful anesthetic lubricant for urinary catheterization and rigid cystoscopy in male adults.

• The Korean Journal of Food And Nutrition
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• v.19 no.3
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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.

• International conference on construction engineering and project management
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• 2009.05a
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• pp.544-549
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• 2009

Alongside the increasingly larger domestic construction projects is the gradual rise in construction waste. Consequently, serious environmental problems emerge. The increase in demand for housing remodeling due mainly to the increase in national income and improvement of quality of life is the main reason for the increase in construction waste. This study was conducted as the basic study for the prevention and reduction of construction waste generated by apartment remodeling; it aimed at identifying the remodeling items and reasons. Toward this end, this study targeted apartments at least 15 years old and conducted a questionnaire survey to determine the remodeled sections and remodeling reasons. As a result of the questionnaire survey, the bathroom, floor finishing, and kitchen furniture recorded the highest ratios in remodeling. Old materials, aesthetic motivation, and pleasant living space composition were cited as the major remodeling reasons. This study is significant as a basic study for generating environmental and economic profits through systematic waste management. Further studies should develop guidelines suitable for construction waste reduction and recycling in line with the construction and demolition phases in case of remodeling.