• Clinical and Experimental Pediatrics
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• 제60권11호
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• pp.373-378
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• 2017

Purpose: The aim of this study was to investigate the statistical properties of four previously developed pediatric coronary artery z score models in healthy Korean children. Methods: The study subjects were 181 healthy Korean children, whose age ranged from 1 month to 15 years. The diameter of each coronary artery was measured using 2-dimensional echocardiography and converted to the z score in the four models (McCrindle, Olivieri, Dallaire, and Japanese model). Descriptive statistical analyses and 1-sample t tests were performed. Results: All calculated z scores had P values of ${\geq}0.050$ using the Kolmogorov-Smirnov test. The one sample t test showed that the mean z scores did not converge to zero except in 1 model, and the mean right coronary artery (RCA) z score was less than zero in all 4 models. The smaller RCA diameter in this study could be associated with the more distal measuring point used to avoid the conal branch. The percentage of subjects with extreme z score values (${\geq}2.0$ and ${\geq}2.5$) for the left main coronary artery (LMCA) seems to be higher in the Dallaire (4.9% and 3.3%) and Japanese models (7.1% and 3.8%). Conclusion: All 4 models showed statistical feasibility of normal distribution. More precise instructions would be needed for the measurement of the RCA. The higher percentage of extreme z scores for the LMCA is compatible with the basic understanding of anatomic variation in the LMCA.

• 대한화학회지
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• 제31권6호
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• pp.576-581
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• 1987

사과무늬잎말이나방의 성 유인물질인 (Z)-11-테트라데센-1-일 아세테이트(1)와 (E)-11-테트라데센-1-일 아세테이트(2)를 합성하여 생물활성시험을 수행하였다. 10-브로모데칸-1-올과 DHP에서 얻어지는 10-브로모데칸-1-올 THP에테르를 아세틸렌소디움음이온과 알킬화시켜 11-도데신-1-올 THP에테르를 합성하였다. 이것을 부틸리튬으로 처리하여 얻어지는 리튬음이온을 브로모에탄과 반응시켜 11-테트라데센-1-올 THP에테르를 얻었다. 이것을 $Pd/BaSO_4$하에서 수소환원시켜 (Z)-11-테트라데센-1-올 THP에테르를 얻었고, $Na/NH_3$와 금속환원시켜 (E)-11-테트라데센-1-올 THP에테르를 얻었다. (Z)-와 (E)-형의 화합물을 보호기를 제거한 후 아세트산무수물로 아세틸화하여 (Z)-11-테트라데센-1-일 아세테이트와 (E)-11-테트라데센-1-일 아세테이트를 각각 얻었다. 합성된 성 페로몬에 대한 사과무늬잎말이나방 숫컷의 성 유인력을 시험해 본 결과 활성이 있음이 밝혀졌다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2000년도 하계학술대회 논문집 A
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• pp.285-288
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• 2000

This paper presents a technique for contingency ranting using line capacity calculation method and outage distribution factors(LODF) which are established by generation shift distribution factors from DC load flow solutions. By using the LODF, the line flow can be calculated a ccording to the modification of base load flow if the contingency occur. To obtain contingency ranting, maximum power tansferred to the load is obtained when load impedance $Z_r$ equal to line impedance $Z_s$. ( $Z_r$/ $Z_s$=1) The proposed algorithm has been validated in tests on a 6-bus test system.

• KSTLE International Journal
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• 제9권1_2호
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• pp.10-12
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• 2008

Silicon micro-patterns were fabricated on Si (100) wafers using photolithography and DRIE (Deep Reactive Ion Etching) fabrication techniques. The patterned shapes included micro-pillars and micro-channels. After the fabrication of the patterns, the patterned surfaces were chemically modified by coating Z-DOL (perfluoropolyether, PFPE) thin films. The surfaces were then evaluated for their micro-friction behavior in comparison with those of bare Si (100) flat, Z-DOL coated Si (100) flat and uncoated Si patterns. Experimental results showed that the chemically treated (Z-DOL coated) patterned surfaces exhibited the lowest values of coefficient of friction when compared to the rest of the test materials. The results indicate that a combination of both the topographical and chemical modification is very effective in reducing the friction property. Combined surface treatments such as these could be useful for tribological applications in miniaturized devices such as Micro/Nano-Electro-Mechanical-Systems (MEMS/NEMS).

• Bulletin of the Korean Chemical Society
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• 제4권2호
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• pp.61-63
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• 1983

A new practical method is described for the synthesis of (Z)-7-eicosen-11-one (1) and (Z)-7-nonadecen-11-one (2), the active principles of the sex pheromone of the peach fruit moth. Lithium anion of 1-octyne (from acetylene and 1-bromohexane) was alkylated with 3-bromo-1-propanol tetrahydropyranyl ether and deprotected to afford 4-undecyn-1-ol, which was oxidized with pyridinium chlorochromate to 4-undecyn-1-al. 4-Undecyn-1-al was treated with 1-nonylmagnesiumbromide or 1-octylmagnesiumbromide to yield 7-eicosyn-11-ol and 7-nonadecyn-11-ol. Jones oxidation, followed by Lindlar catalytic hydrogenation afforded the target compounds. Biological activity of the synthetic pheromones as attractants for males of the peach fruit moth was tested in the field using polyethylene capsules as containers. For each vial containing about 3.0 mg of the synthetic pheromone, the number of trapped moths were counted.

• 근관절건강학회지
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• 제25권1호
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• pp.21-29
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• 2018

Purpose: The purpose of this study was to investigate the effects of a community-based empowerment program for resident leaders participating in the Healthy Apartment project. Methods: The design of this study was a single group pre-post test design. This program was consisted of 4-hour sessions. The total participants were 22 leaders. Results: The participants showed significant changes in social support (Z=-2.33, p=.020), collective action (Z=-3.91, p<.001), conflict and homogeneity (Z=-2.03, p=.042), and community perception index (Z=-3.97, p<.001) as sub factors of the individual level of SC-IQ (Integrated Questionnaire for the Measurement of Social Capital). They also showed significant changes in necessity of the resident organization (Z=-4.13, p<.001), resident participation (Z=-3.84, p<.001), convergence of resident opinion (Z=-3.94, p<.001) and the role of community leaders (Z=-3.94, p<.001) as sub factors of the perception and confidence of resident leaders (Z=-3.85, p<.001). Conclusion: Results indicate that the community-based empowerment program is effective in perceptions of social capital on the individual level and improvement of recognition as resident leaders and confidence for resident leaders.

• 융합정보논문지
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• 제9권5호
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• pp.40-47
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• 2019

본 연구의 목적은 혈액 투석 환자의 변비 정도를 파악하고, 미숫가루가 변비 완화 및 생리적 지표에 미치는 효과를 알아보고자 함이다. S시 소재 종합 병원에서 혈액 투석을 받는 환자 42명을 대상으로 실험군에게 미숫가루 30g을 복용하게 하고 변비 사정 척도 점수와 혈청 Potassium, Phosphorus을 측정하였다. 변비 사정 척도 점수는 실험군이 4.5점, 대조군이 6.5점으로 두 집단 모두 점수가 낮아졌다(z=-2.66, p=.002). Potassium은 실험군이 4.9mmol/l, 대조군이 4.7mmol/l 이었고(z=0.91, p=.960). 혈청 Phosphorus점수는 실험군이 5.3mg/dl, 대조군이 4.7mg/dl 이었으나 (z=0.45, p=.540) 통계적으로 유의하지 않았다. 미숫가루 음용은 혈액 투석환자의 변비 완화를 위한 적절한 간호 중재로 적용될 수 있으며 미숫가루 음용 섭취를 통해 혈액 투석 환자의 변비 완화 간호 중재의 적극인 활용이 임상 실무에서 도움이 될 것으로 생각된다.

• 감성과학
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• 제15권2호
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• pp.201-208
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• 2012

본 연구에서는 심한 소음으로 불쾌감을 주는 스포츠웨어용 PTFE 라미네이팅 투습발수 직물 8종을 대상으로 직물 마찰음의 심리음향학적 특성을 고찰하고, 심리음향학적 특성에 영향을 미치는 직물의 기본 특성과 역학적 특성 간의 관계를 파악함으로써, 직물의 심리음향학적 마찰음을 낮출 수 있는 변인을 찾아내고자 하였다. 직물 마찰음 시뮬레이터를 이용하여 녹음한 직물의 소리에서 Zwicker의 파라미터인 심리음향학적 크기(loudness(Z)), 날카로움(sharpness(Z)), 거칠기(roughness(Z)), 그리고 변동강도(fluctuation strength(Z))를 계산한 뒤, 소리특성에 대한 사후검정 결과에 따라 시료를 덜 시끄러운 PTFE 필름 그룹과 더 시끄러운 PTFE 필름 그룹으로 나누어 마찰음의 심리음향학적 특성과 직물의 역학적 특성, 기본특성간의 관계를 고찰하였다. 심리음향학적 특성 중 loudness(Z)만이 시료의 마찰음과 유의한 관계에 있는 것으로 나타났으며, 분석 결과 직물의 기본 특성에서는 layer가 얇고 필라멘트사를 사용한 직물의 마찰음이 덜 시끄럽게 인지되는 것으로 나타났으며, 직물 마찰음의 심리음향학적 크기에 영향을 미치는 주요변수로는 layer로 것으로 나타났다. 마찰음이 작은 PTFE 필름 그룹의 경우 전단 방향으로의 변형이 어려울수록 마찰음이 시끄나타났다. 시끄러운 마찰음을 갖는 PTFE 필름 그룹의 경우 심리음향학적 크기에 영향을 미치는 주요 변수로 전단이력이 설명 변인으로 포함되었다.

• JSTS:Journal of Semiconductor Technology and Science
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• 제3권4호
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• pp.175-180
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• 2003

In this paper, we present a new method for early depth test for a 3D rendering engine. We add a filter stage to the rasterizer in the 3D rendering engine, in an attempt to identify and avoid the occluded pixels. This filtering block determines if a pixel is hidden by a certain plane. If a pixel is hidden by the plane, it can be removed. The simulation results show that the filter reduces the number of pixels to the next stage up to 71.7%. As a result, 67% of memory bandwidth is saved with simple extra hardware.

• 한국수학교육학회지시리즈A:수학교육
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• 제41권1호
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• pp.109-126
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• 2002

In this thesis. we estimated the good reliability coefficient ${\beta}$$\sub$k/ that is unbiased, consistent and more efficient than Cronbach's ${\alpha}$$\sub$k/ in splitting of a test into several formats of subtests and several properties of ${\beta}$$\sub$k/ are also represented. The tables of coefficients of skewness and kurtosis are represented to test the significance of departures from normality. We got the cumulative normal plots of z'from the distribution which is departed from normality using the Bock's approximation procedure and we finally enumerated the transformed standardized scores z'and a new raw score X' which enable us to proceed further evaluation procedures depending on our assessment policy.