• Nuclear Engineering and Technology
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• 제49권6호
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• pp.1240-1249
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• 2017

An essential component of the neutron transport solver is the resonance self-shielding calculation used to determine equivalence cross sections. The neutron transport code, MPACT, is currently using the subgroup self-shielding method, in which the method of characteristics (MOC) is used to solve purely absorbing fixed-source problems. Recent efforts incorporating multigroup kernels to the MOC solvers in MPACT have reduced runtime by roughly $2{\times}$. Applying the same concepts for self-shielding and developing a novel lumped parameter approach to MOC, substantial improvements have also been made to the self-shielding computational efficiency without sacrificing any accuracy. These new multigroup and lumped parameter capabilities have been demonstrated on two test cases: (1) a single lattice with quarter symmetry known as VERA (Virtual Environment for Reactor Applications) Progression Problem 2a and (2) a two-dimensional quarter-core slice known as Problem 5a-2D. From these cases, self-shielding computational time was reduced by roughly $3-4{\times}$, with a corresponding 15-20% increase in overall memory burden. An azimuthal angle sensitivity study also shows that only half as many angles are needed, yielding an additional speedup of $2{\times}$. In total, the improvements yield roughly a $7-8{\times}$ speedup. Given these performance benefits, these approaches have been adopted as the default in MPACT.

• 대한바이러스학회지
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• 제26권1호
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• pp.9-22
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• 1996

Respiratory Syncytial virus (RSV) is an important cause of acute lower respiratory tract infections in human, with infants and young children being particularly susceptible. In the temperate zones, sharp annual outbreaks of RSV occur during the colder months, in both the northern and the southern hemisphere. RSV is unusual in that it can repeatedly reinfect individuals throughout life and infect babies in the presence of maternal antibody. RSV isolates can be divided into two subgroups, A and B, on the basis of their reactions with monoclonal antibodies, and the two subgroups are also distinct at the nucleotide sequence level. The specific diagnosis of RSV infection was best made by isolation of virus in tissue culture, identification of viral antigen, or by specific serologic procedures. Recently, rapid detection of RSV and analysis of RSV strain variation became possible by development of methods of reverse transcription and polymerase chain reaction amplification. In this study, to determine the genetic diversity of RSV found in Korea, 173 bp and 164 bp spanning selected regions of the RSV F and SH genes were enzymatically amplified and sequenced, respectively. Eight for F gene and three for SH gene were detected in 66 nasopharyngeal swap samples tested. Two major antigenic subgroups, A and B were confirmed from Korean samples (seven for subgroup A and one for subgroup B). At the nucleotide level of the F gene region, Korean subgroup A strains showed 95-99% homologies compared to the prototype A2 strain of subgroup A and 93-100% homologies among Korean subgroup A themselves. For the SH gene region, Korean subgroup A strain showed 97.5% homology compared to the prototype A2 strain of subgroup A, and Korean subgroup B strain showed 97% homology compared to the prototype 18537 strain of subgroup B. Most of base changes were transition and occured in codon position 3, which resulted in amino acid conservation. Using the maximum parsimony method, phylogenetic analysis indicated that Korean RSV strains formed a group with other RSV strains isolated from the United States, Canada, the Great Britain and Australia.

• 한국산림과학회지
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• 제79권1호
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• pp.42-55
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• 1990

가산지역(架山地域) 삼림식생(森林植生)을 식물사회학적(植物社會學的) 방법(方法)으로 분석(分析)하였던바 다음과 같은 결과(結果)를 얻었다. 1) 이 지역(地域) 삼림식생(森林植生)은 산지림(山地林)(소나무-물오리나무군락(群落))과 고원분지림(高原盆地林)(병꽃나무-뱀고사리군락(群落))으로 구분(區分)할 수 있었다. 2) 산지림(山地林)(I. 소나무-물오리나무군락(群落))은 I-A. 서어나무군(群), I-B. 고로쇠나무군(群)으로 구분(區分)되었고, I-A. 서어나무군(群)은 I-A-1. 쪽동백나무소군(小群), I-A-2. 비목나무소군(小群), I-A-3. 전형소군(典型小群), I-A-4. 산초나무소군(小群)으로 구분(區分)되었다. 3) 고원분지림(高原盆地林)(II. 병꽃나무-뱀고사리군락(群落))은 II-A. 서어나무군(群), II-B. 까치박달-다래군(群), II-C. 전형군(典型群)으로 구분(區分)되었고, II-A. 서어나무군(群)은 II-A-1. 노린재나무소군(小群), II-A-2. 전형소군(典型小群), II-A-3. 고로쇠나무소군(小群)으로 구분(區分)되었다. 소산식물상(所產植物相)은 105과(科), 350속(屬), 515종(種), 2아종(亞種), 12품종(品種), 87변종(變種)인 총(總) 616 종류(種類)가 분포(分布)하고 있었다.

• 대한수학회보
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• 제44권4호
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• pp.817-823
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• 2007

In this paper, we develop a simple method for computing the stabilizer subgroup of a subgroup of $$D(g)={{\alpha}{\in}\mathbb{F}_q|there\;is\;a\;{\beta}{\in}{\mathbb{F}}^x_q\;such\;that\;{\beta}^n=g(\alpha)}$$ in $PSL_2(\mathbb{F}_q)$, where q is a large odd prime power, n is a positive integer dividing q-1, and $g(x){\in}\mathbb{F}_q[x]$. As an application, we construct new infinite families of 3-designs (cf. Examples 3.4 and 3.5).

• 대한수학회지
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• 제50권6호
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• pp.1213-1222
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• 2013

This paper deals with sufficiency conditions for irreducibility of certain induced modules. We also construct irreducible representations for a group G over a field $\mathbb{K}$ where the group G is a semidirect product of a normal abelian subgroup N and a subgroup H. The main results are proved with the assumption that char $\mathbb{K}$ does not divide |G| but there is no assumption made of $\mathbb{K}$ being algebraically closed.

• 초등상담연구
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• 제11권2호
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• pp.153-169
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• 2012

초등학생의 또래관계가 발달에 미치는 영향을 알아보기 위한 방법으로 먼저, 또래관계를 어떻게 소집단 형태로 묶는(grouping) 것이 가장 합리적인 방법인가를 찾아내는 것이 연구의 목적이었다. 이에 따라 지각자료와 심리적 선호도 자료에 의한 또래관계 소집단 분류의 방법 간에는 서로 어떤 차이가 있는지를 알아보는 것이 연구문제로 설정되었다. 연구 대상은 부산과 울산의 초등학교 중학년인 3-4학년 아동 가운데 남자는 3학년, 여자는 4학년의 2학급이었다. 연구 문제를 검증하기 위한 질문지는 두 가지로 지각 자료 질문지와 심리적 선호도 질문지였다. 지각 자료는 공유인접수를 바탕으로 상관관계의 값을 적용하여 또래관계의 소집단으로 분류 되었으며, 선호도 자료는 이자관계를 확장하여 삼자관계 이상의 소집단으로 또래관계를 분류하는 방법을 적용하였다. 본 연구의 결과, 여자 아동의 경우에는 지각 자료에 의한 소집단과 선호도 자료에 의한 소집단간에 매우 유사한 분류의 일치성이 나타났지만, 남자 아동의 경우에는 두 가지 분류 방법간에 분류의 차이가 나타났다. 이러한 결과로 볼 때, 남자 아동의 경우에는 개별 아동간의 심리적 불일치에도 불구하고 또래관계를 형성할 가능성이 있지만, 여자 아동의 경우에는 심리적으로 일치될 때 또래관계가 형성되는 것으로 확인되었다. 이러한 결과는 양성간의 또래관계 형성 과정이 다를 수 있음을 시사한다. 따라서 남자 아동의 또래관계를 합리적으로 분류하기 위한 후속연구로 담임 교사에 의한 소집단 분류, 지각 자료에 의한 소집단 분류, 선호도 자료에 의한 소집단 분류의 세 가지 분류 방법 간의 적합성에 대한 비교 작업이 수행될 필요성이 있었다.

• The Journal of Advanced Prosthodontics
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• 제5권3호
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• pp.296-304
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• 2013

PURPOSE. The aim of this study was to evaluate the effect of polishing and glazing on the color and spectral distribution of monolithic zirconia. MATERIALS AND METHODS. Forty-five monolithic zirconia specimens ($16.3mm{\times}16.4mm{\times}2.0mm$) were fabricated and divided into 5 groups according to the number of A2-coloring liquid applications (Group I to V). Each group was divided into 3 subgroups according to the method of surface treatments (n=3): N: no treatment; P: polishing; G: glazing. Color and spectral distribution of five different areas of each specimen were measured according to CIELAB color space in the reflectance mode relative to the standard illuminant D65 on a reflection spectrophotometer. Data were analyzed using one-way ANOVA followed by Tukey's HSD test, Pearson correlation and regression analysis (${\alpha}$=.05). RESULTS. There was a significant difference in CIE $L^*$ between Subgroup N and P, and in CIE $b^*$ between Subgroup P and G in each group. Spectral reflectance generally decreased in Subgroup P and G in comparison with Subgroup N. Color differences between Subgroup P and G were within the perceptibility threshold (${\Delta}E{^*}_{ab}$ < 3.7) in most groups. Highly significant correlation was found between CIE $b^*$ and each subgroups as the number of coloring liquid applications increased ($R^2$ >0.88, P<.001). CONCLUSION. A perceptible color difference can be detected after polishing of monolithic zirconia. Polishing decreases the lightness, and glazing also decreases the lightness, but increases the yellowness of monolithic zirconia.

• 모자간호학회지
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• 제4권1호
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• pp.41-51
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• 1994

The purposes of this study were to identify responses of nursing students following clinical maternity nursing practice, to develop data of further effective clinical maternity nursing practice, to understand nursing students perceive the natural maturation process toward pregnancy delivery and puerperal process, to help the nursing students achieve personality growth and development through clinical maternity nursing practice. The subjects were 35 senior nursing students from the Department of Nursing Science of Chung-Ang University. The data were collected from the 1st semester (Feb.22$\sim$June 9) to the 2nd semester(Aug.23$\sim$Nov.10), 1993 through self-reporting using an open ended questionnaire about perception and feelings regarding the normal delivery process. The data analysis used descriptive method. Results of the study were as follows : 1. Following clinical practice in maternity nursing, the responses of the nursing students were collected included both positive and negative aspects. The positive responses were classified in to four categories and each category included subgroups. One group, labelled as $\ulcorner$The birth of noble life$\lrcorner$ had a subgroup, (I felt the mystery and wonder of life), another group, $\ulcorner$After delivery, comfort and satisfaction$\lrcorner$ with the subgroup (I can bear to see the comfort and relief beyond pain) (C/S is better than vaginal delivery) (Very easy), the 3rd group, $\ulcorner$ I realized family friendship and support$\lrcorner$ with subgroup (Honorable, Magnificient) (I thank my parents ) (It's good to looking at my husband's support), and the 4th group, $\ulcorner$The birth of a healthy baby$\lrcorner$, with its subgroup, (baby looks pretty and healthy). 2. The negative responses were classified in eight categories and each category included subgroups. One group labelled as $\ulcorner$Fear$\lrcorner$, had subgroups of (Terrible, Horrible) (Shock) (Dread), another group, $\ulcorner$Tension$\lrcorner$, and its subgroup, (I became tense about stories heard before clinical practice), the 3rd group, $\ulcorner$surprise$\lrcorner$ and its subgroup (I was surprised at the delivery process), the 4th group, $\ulcorner$Power lessness$\lrcorner$ and its subgroup, (I watched the labor pain impatiently), the 5th group $\ulcorner$Apathy$\lrcorner$ ; and its subgroup, (I didn't feel the empathy for the labor pain of the pregnant women), the 6th group, $\ulcorner$Disgust$\lrcorner$ and its subgroup, (Disgust, Embarrassed), the 7th group, $\ulcorner$Inevitable destiny$\lrcorner$ and its subgroups (necessity of self-sacrifice and difficulty) (I accepted it as a women's destiny) (I can't do it), the last group, $\ulcorner$There seems to be trouble$\lrcorner$ and its subgroup, (It seems to have been a little too hard for mother and baby). Suggestions for further studies are as follows : 1. Nursing students should receive intensive education about $\ulcorner$The birth of noble life$\lrcorner$ $\ulcorner$After delivery, comfort and satisfaction$\lrcorner$ $\ulcorner$I realized family friendship and support$\lrcorner$ $\ulcorner$The birth of a healthy baby$\lrcorner$, so that a more positive attitude can be developed before clinical maternity nursing. 2. Nursing students should be given an orientation which is reality based and related clinical maternity nursing (using for A.V. Materials), so that they will not feel they tension, of the negative categories. 3. Nursing students should be received articles on Pain Relief Method, so that they will be prepared activie and positive in the clinical practice, and therefore they will not feel the powerlessness, of the negative categories. 4. F/U for responses of nursing students should be checked following clinical maternity nursing to evaluate the effects of the instruction.

• 한국산림과학회지
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• 제84권2호
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• pp.247-257
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• 1995

우리나라 특산 수종인 구상나무림(林)의 보존과 조림 및 임업경영에 필요한 정보를 체계화 시킬 목적으로 ZM방식을 통한 군락분류를 하였던 바 다음과 같이 요약할 수 있었다. 구상나무림(林)은 구상나무-신갈나무군락과 구상나무 제주조릿대군락으로 구분되었으며 구상나무 신갈나무군락은 미역줄나무군, 금마타리군 및 전형군으로 구분되었고, 미역줄나무군은 전형소군, 참나물소군 미 원추리 소군으로 구분되었다. 구상나무-제주조릿대군락은 매발톱나무군, 마삭줄군 및 전형군으로 구분되었으며 매발톱나무군은 전형소군과 노루귀소군으로, 마삭줄근은 노루귀소군과 전형소군으로 구분되는 등 총 10개의 식생단위로 구분되었다. 일치법으로 검토한 바 구상나무-신갈나무군락은 소백산맥에 위치하는 지리산, 덕유산, 가야산에서 출현하였고, 구상나무-제주조릿대군락은 한라산에서 출현하는 등 지리적으로 구분되었고, 군락단위간에는 해발과 지형이 복합적으로 영향을 미치는 경향이었다. 식생단위와 구상나무의 흉고직경 및 수고간에는 구상나무-신갈나무군락의 평균흉고직경과 평균수고가 각각 28.4cm, 10.6m로서 구상나무-제주조릿대군락의 평균흉고직경과 수고가 23.6cm, 6.3m인데 비하여 큰 편이었고 구상나무-신갈나무군락 중에서는 금마티리군이 평균흉고직경과 수고가 20cm, 5m로서 가장 작었으며, 구상나무-제주조릿대군락 중에서는 전형군의 평균흉고직경과 수고가 4cm와 3m로서 가장 작았다.

• 핵의학기술
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• 제14권1호
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• pp.143-146
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• 2010

Insulin은 공복시에 저혈당인 환자의평가, 당뇨병의 분류 및 예측, ${\beta}$-세포의 활성도 평가, 인슐린 내성 조사에 임상적 유용성이 있다. 이에 통계적 분석으로 insulin의 정상 참고치를 설정함으로써 insulin 검사의 유용성을 증가시키고자 한다. 2008년 5월부터 8월까지 본원 건진 센터에 내원한 환자 6648명 중 당뇨병의 가족력이 있는 사람, 당뇨 medication 중인 사람, 혈당 상승의 과거력이 있는 사람, 정상 공복혈당 100 mg/dL 이상인 사람, BMI 18.5~22.9 $kg/m^2$의 범위를 벗어나는 사람, HbA1c 6.5% 이상인 사람을 exclusion criteria로 설정하였다. Subgroup은(하위집단의 평균치 차/95% 참고범위 간격 차)${\times}$100의 산출값이 기준치 25%보다 큰 경우에 한하여 하위집단을 구분 설정하였다. 성별과 연령으로 subgroup의 참고치 설정여부를 확인하였고, Bayesian's method와 Hoffman's method로 통계적 분석을 실시하여 정상 참고치를 설정하였다. 남녀의 insulin 평균치 차이가 0.317로 산출값이 3.34%로 성별간 subgroup의 설정은 필요하지 않다. 데이터의 평균나이인 45세를 기준으로 한 산출값은 5.83%로 연령간 subgroup의 설정 또한 필요하지 않다. Bayesian 법으로 insulin의 평균은 5.403 uIU/mL로 표준편차 2.720으로 ${\pm}3SD$를 벗어난 94명을 제외한 6554명을 대상으로 분석한 결과 정상 참고치는 1.5~11.0 uIU/mL이다. Hoffmann 법을 통한 통계적 분석은 insulin값을 log insulin값으로 변환하여 정규분포를 만든 후${\pm}3SD$를 벗어난 9명을 제외한 6639명을 대상으로 분석한 결과, 정상 참고치가 1.8~12.8 uIU/mL이다. Kit 내 보고되어 있는 정상 참고치 1.7~11.8 uIU/mL와 비슷한 결과 값인 Hoffmann 법으로 통계적 분석한 결과인 1.8~12.8 uIU/mL로 insulin 정상 참고치를 설정하였다. 이는 당뇨병 평가에 중요한 역할을 하는 insulin의 정상 참고치를 설정함으로써 검사의 유용성을 높일 것으로 여겨진다.