• Environmental Engineering Research
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• 제18권1호
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• pp.37-43
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• 2013

Water distribution pipes installed underground have potential risks of pipe failure and burst. After years of use, pipe walls tend to be corroded due to aggressive soil environments where they are located. The present study aims to assess the degree of external corrosion of a distribution pipe network. In situ data obtained through test pit excavation and direct sampling are carefully collated and assessed. A statistical approach is useful to predict severity of pipe corrosion at present and in future. First, criteria functions defined by discriminant function analysis are formulated to judge whether the pipes are seriously corroded. Data utilized in the analyses are those related to soil property, i.e., soil resistivity, pH, water content, and chloride ion. Secondly, corrosion factors that significantly affect pipe wall pitting (vertical) and spread (horizontal) on the pipe surface are identified with a view to quantifying a degree of the pipe corrosion. Finally, a most reliable model represented in the form of a multiple regression equation is developed for this purpose. From these analyses, it can be concluded that our proposed model is effective to predict the severity and rate of pipe corrosion utilizing selected factors that reflect the fuzzy soil environment.

• 한국구조물진단유지관리공학회 논문집
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• 제6권4호
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• pp.189-199
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• 2002

This study is intended to propose a systematic procedure for the development of the conditional assessment based on the safety of structures and the cost effective performance criteria for designing and upgrading of bridge structures. As a result, a set of cost function models for a life cycle cost analysis of bridge structures is proposed and thus the expected total life cycle costs (ETLCC) including initial (design, testing and construction) costs and direct/indirect damage costs considering repair and replacement costs, human losses and property damage costs, road user costs, and indirect regional economic losses costs. Also, the optimum safety indices are presented based on the expected total cost minimization function using only three parameters of the failure cost to the initial cost (${\tau}$), the extent of increased initial cost by improvement of safety (${\nu}$) and the order of an initial cost function (n). Through the enough numerical invetigations, we can positively conclude that the proposed optimum design procedure for bridge structures based on the ETLCC will lead to more rational, economical and safer design.

• 패션비즈니스
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• 제25권4호
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• pp.14-35
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• 2021

This study compares and analyzes the designs of Burberry creative directors, Christopher Bailey and Riccardo Tisci. For this purpose, 322 photographs (176 Christopher Bailey and 146 Riccardo Tisci) were collected and the data analysis criteria were classified into color, shape, material, decoration, item, and fashion style. With respect to the data analysis method, statistical analysis and content analysis were combined. First, the design characteristics of Christopher Bailey top and bottom combined bright tone, tone-in-tone color scheme, H-line, heterogeneous material combination, and smart casual appeared very frequently. Second, the design characteristics of Riccardo Tisci top and bottom combined were monotone, tone-on-tone color scheme, H-line, heterogeneous material combinations, and street culture. Third, the design differences between creative directors were significantly different in color, tone, color arrangement, pattern, material type, material combination, detail, top and bottom items, and fashion style. Burberry men's wear maintains Burberry's traditional design identity with achromatic colors, beige-based colors, and beige checks. Christopher Bailey's design direction is characterized by modernity in a casual mood that emphasizes practicality. The design direction of Riccardo Tisci is characterized by a wide gap between images in a semi-formal style that emphasizes Burberry's tradition and a free-spirited casual style.

• 자원환경지질
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• 제54권2호
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• pp.213-232
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• 2021

Ore criteria at the Sheba Deposit indicate orogenic mineralization type. Rocks and mineral assemblages suggest low formation-temperature of green-schist facies. Pyrite found in two generations; Type1 is irregular grains, contains higher arsenic and gold contents, compared to the relatively younger phase Type2 pyrite, which is composed of euhedral grains, found adjacent to late quartz-carbonate veins or at rims of type1 pyrite. Two gold generations were identified; type1 found included in sulphides (mainly pyrite). The second gold type was remobilized (secondary) into free-lodes within silicates (mainly quartz). Gold fineness is high, as gold contains up to 95 wt. % Au, Ag up to 3.5 wt. %, and traces of Cu, Ni, and Fe. Pyrite type2 contains tiny mineral domains (rich in Al, Mn, Hg, Se, Ti, V, and Cr). Zoning, and replacement textures are common, suggesting multiple mineralization stages. The distribution and relationships of trace elements in pyrite type2 indicate three formation patterns: (1) Al, Mn, Hg, Se, Ti, V, Cr, and Sn are homogeneously distributed in pyrite, reflecting a synchronous formation. (2) As, Ni, Co, Zn, and Sb display heterogeneous distribution pattern in pyrite, which may indicate post-formation existence due to other activities. (3) Au and Ag show both distribution patterns within pyrite, suggesting that gold is found both in microscopic phases and as chemically bounded phase.

• 대한소아치과학회지
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• 제28권3호
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• pp.363-368
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• 2001

광중합형 복합레진은 일부 성분들이 강한 광학-전자기선에 노출됨으로써 경화된다. 최초의 제품들은 자외선을 이용하여 중합되었다. 초기의 이러한 제품들은 작업시간의 조절가능 기포 형성 감소, 색 안정성 향상으로 각광받았지만, 자외선의 위해 성과 얕은 중합깊이를 극복하지 못해 결국 가시광선 중합형으로 대체되었다. 가시광선 중합형 복합레진의 중합완성도는 단량체(monomer)에서 복합체(polymer)로의 변환율에 의해 결정된다. 결국 수복물의 성공여부는 조사된 가시광선의 중합능력과 밀접한 연관성을 갖는다. 이번 조사의 목적은 현재 임상(치과 병 의원)에서 사용되고 있는 광중합기의 광도를 여러 연구를 통하여 그 신뢰성이 입증된 digital radiometer를 이용해 평가하고, 3가지 기본부품의 결함을 검증해서 임상가들에게 유익한 정보를 주기 위함이다. 조사 결과, 조사 대상 광중합기 중 17.8%가 적절한 중합에 부적절한 상태에 있으며, 46.6%가 광 조사시간을 연장할 필요가 있는 것으로 드러나, 광조사기의 절반 이상이 수복물의 성공적인 중합을 위해서는, 중합시간의 연장을 필요로 하거나, 기계적 결함으로 점검을 필요로 하는 상태에 있었다. 이번 조사로, 현재 치과 병, 의원에서 사용중인 광조사기의 부품성능과 그 관리에 문제가 있음을 알 수 있다. 이러한 결과는, 최근에 이루어진 외국의 조사에서와 유사하였다. 광조사기를 이용한 수복치료의 성공과, 구입당시 수준의 적절한 품질(quality)을 유지하기 위해서는, 광조사기 관리와 부품 교체에 대한 임상가들의 이해가 필요할 것으로 보인다.

• Clinics in Shoulder and Elbow
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• 제1권2호
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• pp.205-211
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• 1998

저자들은 상완골 근위부의 골절탈구로 일차성 견관절 반치환술로 치료받은 환자 25례중 14례를 대상으로 치료결과를 분석하여 다음과 같은 결론을 얻었다. 1. 전례에서 동통은 소실되거나 완화되었으나 Neer의 평가에 따라 총 14례중 5례에서만 만족할만 한 결과를 믿었으며 나머지 9례에서는 불만족한 결과를 보였다. 2. 수상시 상완곤두의 분쇄상이 심하거나, 수술이 지연되어 골편치 연화가 심한 경우 상완골 길이와 humeral offset의 유지가 힘들었으며, 견관절 반치환술 시팽한 측이 정상측보다 1cm 이상 단축을 보인 경우가 5례였으며 이 경우 능동적 견관절 운동범위가 정상측보다 감소되었다. 3. 견관절 반치환술은 분쇄상 상완골 근위부 골절에서 사용되어지며 동통의 감소와 기능의 호전은 있으나 완전한 회복은 어려우며 수술시 연부조직 손상이 적고 적당한 후염각, 결절의 재건 과 회전근개의 수복은 필수적이다. humeral offset과 길이의 유지는 술 후 능동적 견관절 운동 범위의 향상에 영향을 미치며 아울러 환자의 협조하에 체계적인 재활운동이 필요할 것으로 사료된다.

• Journal of Chest Surgery
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• 제54권5호
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• pp.369-376
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• 2021

Background: Sutureless and rapid deployment valves for aortic valve replacement (AVR) were introduced in Korea in December 2016. This study evaluated changing trends in the prosthetic valves used for AVR in Korea after the introduction of sutureless and rapid deployment valves. Methods: From December 2016 to December 2018, 4,899 patients underwent AVR in Korea. After applying the exclusion criteria, 4,872 patients were analyzed to determine changes in the type of prosthetic valve used for AVR. The study period was divided into 5 groups corresponding to 5-month intervals. Results: The total number of AVR cases was 194.88±28.78 per month during the study period. Mechanical valves were used in approximately 27% to 33% of cases, and the proportion of mechanical valve use showed a tendency to decrease, with marginal significance overall (p=0.078) and significant decreases in patients less than 60 years of age and in men (p=0.013 and p=0.023, respectively). The use of sutureless valves increased from 13.4% to 25.8% of cases (p<0.001), especially in elderly patients (>70 years) and those requiring concomitant surgery. In a comparison between sutureless and rapid deployment valves, the use of Perceval S valves (a type of sutureless valve), gradually increased (p<0.001). Conclusion: After the introduction of sutureless and rapid deployment valves in Korea, the rate of use of these new valves remarkably increased, especially in elderly patients and those requiring concomitant surgery. Further studies should investigate the clinical outcomes of these new prostheses.

• 한국임상약학회지
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• 제23권4호
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• pp.307-315
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• 2013

Objective: Colistimethate was first became available in 1950s and used until the early 1980s to treat infections caused by gram-negative bacteria and was abandoned due to its nephrotoxicity and neurotoxicity. However, it was recently reintroduced into the clinical practices due to emergence of multidrug-resistance gram-negative bacteria, particularly Pseudomonas aeruginosa and Acinetobacter baumanii. Therefore, it is increasingly used in the intensive care unit settings as a salvage therapy. This study was designed to investigate the incidence rates and risk factors of acute kidney injury associated with colistimethate by using the standardized definition in critically ill patients. Methods: This study retrospectively reviewed the electronic medical records of 71 adult patients above 18 years old receiving intravenous colistimethate at least 48 hours at intensive care unit, university-affiliated hospital from Nov 2012 to Aug 2013 and excluded patients with end-stage renal disease (ESRD) and required renal replacement therapy before initiation of the colistimethate therapy. Acute kidney injury (AKI) was determined by using the standardized RIFLE criteria, classified with risk, injury, failure, loss and ESRD according to serum creatinine (Scr) levels. Results: Among the 71 patients included in the analysis, AKI developed in 40 patients (56.3%) and 6 patients (8.4%) had irreversible kidney injury. AKI occurred within 5 days in 20 patients (50.0%). Maximum Scr level showed a significant increase in the patients with AKI ($1.92{\pm}0.86mg/dL$ vs. $1.12{\pm}0.46mg/dL$ p=0.001), maximum BUN also increased ($64.2{\pm}28.7mg/dL$ vs. $48.4{\pm}24.9mg/dL$ p=0.017) and minimum creatinine clearance (CLcr) was significantly decreased in the patients with AKI than non-AKI ($34.5{\pm}18.6ml/min$ vs. $64.4{\pm}33.7ml/min$ p=0.185). The patients with AKI had significantly longer duration of colistimethate therapy ($21.1{\pm}17.0$ days vs. $13.0{\pm}11.5$ days, p=0.020) and larger cumulative doses of colistimethate ($6465.9{\pm}4717.0mg$ vs. $4438.1{\pm}3426.7mg$, p=0.040). Conclusion: The incidence and severity of AKI associated with colistimethate in critically ill patients was high and serious. Drug monitoring program should be performed to shorten duration of therapy and reduce cumulative dose from initiation of colistimethate therapy for minimizing AKI of colistimethate.

• 한국환경복원기술학회지
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• 제14권1호
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• pp.11-22
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• 2011

This study was established to build and suggest the Ecological Performance Standards for replaced wetlands as the mitigation strategies for the construction projects. The request performance and assessment factors and standards were derived by bibliographic review and verified by the field survey for the reference wetlands. And the weights for each factor were derived by AHP(Analytical Hierarchy Process) method. The results are as follows : 1) Assessment factors were induced by in-depth research of many wetland assessment models and benchmarks evaluated ecological functions. This study proposed final 12 assessment factors through ecological specialist and experts interviews added with literature analysis. 2) 10 natural wetlands were selected as Reference Wetlands as the measure to propose assessment factors and assessment criteria. Those reference wetlands are well-conserved inland natural wetlands classified to the one having worthy to conserve (grade "high") according to RAM(Rapid Assessment Method). Reference wetlands chosen by the study are Parksilji, Jeongyangji, Mulkubi, Bawineupkubi, Jilnalneup, Jinchonneup, Doomoso, Haepyung wetland, Whangjeong wetland, and Whapo wetland. The research developed assessment criteria for the performance assessment factors based on several explorations of the reference wetlands. 3) "Requiring performance" of replaced wetlands is defined as "to carry out similar or same ecological functions provided by natural wetlands", in overall. The detailed requiring performances are as follows; ${\bullet}$ to play a role of wildlife habitats ${\bullet}$ to have biological diversity ${\bullet}$ to connect with other ecosystems ${\bullet}$ to provide water environment to perform good ecological functions 4) The assessment factors for required performance are categorized by wildlife habitat function, biological diversity, connectivity of adjacent ecosystem, and water environment. Wildlife habitat category is consisted of wildlife habitat creation, size of replacement wetland, and site suitability. Biological diversity category contains the number of plant species, the number of wildlife species, and number of protected species as the sub-factors. Connectivity of adjacent ecosystem is comprised of wildlife corridor, green network and distance from other ecosystem. Finally, water environment make up with water quality, depth of water body, and shape of waterfront. 5) Finally, every assessment factors were verified and weighted by the AHP methods and the final standards were proposed. The weights of factors of requiring performance suggested as habitat (0.280), connectivity (0.261), diversity (0.260), hydraulic environment (0.199). And those of detailed sub-factors are site suitability (0.118), protected species (0.096), distance to neighbor ecosystem (0.093), habitat creating (0.091), green corridor (0.090) etc.

• 대한간호학회지
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• 제45권2호
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• pp.293-305
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• 2015

Purpose: The aim of the study was to assess and identify gender differences in factors associated with prevalence, awareness, and treatment of osteoporosis. Methods: Data for 3,071 men and 3,635 women ($age{\qeq}50$) from the Korea National Health and Nutrition Examination Survey 2008~2011 were included. Osteoporosis was defined by World Health Organization T-score criteria. Impact factors and odds ratios were analysed by gender using multivariate logistic regression. Results: Osteoporosis prevalence rates were 7.0% in men and 40.1% in women. Osteopenia rates were 45.5% and 46.0% respectively. Among respondents with osteoporosis, 7.6% men and 37.8% women were aware of their diagnosis. Also 5.7% men with osteoporosis and 22.8% women were treated. Higher prevalence was found among respondents who were older, at lower socioeconomic levels, with lower body mass index and shorter height in both genders, and among women with fracture history, and non-hormonal replacement therapy. Awareness and treatment rates for the risk groups were similar compared to the low risk controls for both genders. Fracture history increased awareness and treatment rates independently for both genders. Women with perceived poor health status and health screening had increased awareness and treatment rates, but not men. Conclusion: Results indicate that postmenopausal women have a higher prevalence of osteoporosis than men and awareness and treatment rates were higher than for men. Despite gender difference in prevalence, osteoporosis was underdiagnosed and undertreated for both genders. Specialized public education and routine health screenings according to gender could be effective strategies to increase osteoporosis awareness and treatment.