• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2005년도 ICCAS
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• pp.631-637
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• 2005

This paper presents a stiffness analysis method for a low-DOF parallel manipulator, which takes into account of elastic deformations of joints and links. A low-DOF parallel manipulator is defined as a spatial parallel manipulator which has less than six degrees of freedom. Differently from the case of a 6-DOF parallel manipulator, the serial chains in a low-DOF parallel manipulator are subject to constraint forces as well as actuation forces. The reaction forces due to actuations and constraints in each limb can be determined by making use of the theory of reciprocal screws. It is shown that the stiffness model of an F-DOF parallel manipulator consists of F springs related to the reciprocal screws of actuations and 6-F springs related to the reciprocal screws of constraints, which connect the moving platform to the fixed base in parallel. The $6{times}6$ stiffness matrix is derived, which is the sum of the stiffness matrices of actuations and constraints. The six spring constants can be precisely determined by modeling the compliance of joints and links in a serial chain as follows; the link can be considered as an Euler beam and the stiffness matrix of rotational or prismatic joint can be modeled as a $6{times}6$ diagonal matrix, where one diagonal element about the rotation axis or along the sliding direction is zero. By summing the elastic deformations in joints and links, the compliance matrix of a serial chain is obtained. Finally, applying the reciprocal screws to the compliance matrix of a serial chain, the compliance values of springs can be determined. As an example of explaining the procedure, the stiffness of the Tricept parallel manipulator has been analyzed.

• 아동학회지
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• 제38권2호
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• pp.133-148
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• 2017

Objective: This study focused on the stability and reciprocal effects between abuse and neglect by parents and adolescent depression and delinquency. We examined both parent and child effects by adopting the transactional model proposed by Sameroff (2009). Methods: Using autoregressive cross-lagged modeling, data from the $2^{nd}$ to the $4^{th}$ wave of the Korean Children and Youth Panel Study (KCYPS) were analyzed. The sample consisted of 1,982 adolescents who were $8^{th}$ graders in 2011. Data were collected at three different phases: when participants were in $8^{th}$ grade (T1), $9^{th}$ grade (T2) and $10^{th}$ grade (T3). Results: First, the effects of abuse and neglect by parents and adolescent depression and delinquency showed stability from the $8^{th}$ to the $10^{th}$ grade. Second, abuse at T1 and T2 had effects on adolescent delinquency at T2 and T3, respectively, but not on adolescent depression. In terms of child effects, abuse was influenced by adolescent depression only. Adolescent depression and delinquency had no reciprocal effects. Finally, there were reciprocal effects between neglect on one hand and adolescent depression and delinquency on the other. That is, there were child effects as well as parent effects. No significant effects were found in the reciprocal relations between adolescent depression and delinquency. Conclusion: The present study found the stability of abuse and neglect by parents and adolescent depression and delinquency. Furthermore, this study identified the child effects as well as parent effects, thus supporting the transactional model of neglect by parents and adolescent depression and delinquency.

• 한국정보통신학회논문지
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• 제11권1호
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• pp.46-55
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• 2007

다음은 부동소수점 역수 및 역제곱근 계산에 많이 사용하는 뉴톤-랍손 알고리즘은 일정한 횟수의 곱셈을 반복하여 계산한다. 본 논문에서는 뉴톤-랍손 알고리즘의 반복 과정의 오차를 예측하여 오차가 정해진 값보다 작아지는 시점까지 반복 연산하는 개선된 뉴톤-랍손 알고리즘을 제안한다. 본 논문에서 제안한 알고리즘은 입력 값에 따라서 곱셈 횟수가 다르므로, 평균 곱셈 횟수를 계산하는 방식을 유도하고, 여러 크기의 근사 테이블에서 단정도실수 및 배정도실수의 역수 및 역제곱근 계산에 필요한 평균 곱셈 횟수를 산출한다. 이들 평균 곱셈 횟수를 종래 알고리즘과 비교하여 본 논문에서 제안한 알고리즘의 우수성을 증명한다. 본 논문에서 제안한 알고리즘은 오차가 일정한 값보다 작아질 때까지만 반복 연산을 수행하므로 역수 및 역제곱근 계산기의 성능을 높일 수 있고 최적의 근사 테이블을 구성할 수 있다. 본 논문의 연구 결과는 디지털 신호처리, 컴퓨터 그라픽스, 멀티미디어, 과학 기술 연산 등 부동소수점 계산기가 사용되는 분야에서 폭 넓게 사용될 수 있다.

• Asian-Australasian Journal of Animal Sciences
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• 제32권12호
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• pp.1816-1825
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• 2019

Objective: We tried to analyze allele-specific expression in the pig neocortex using bioinformatic analysis of high-throughput sequencing results from the parental genomes and offspring transcriptomes from reciprocal crosses between Korean Native and Landrace pigs. Methods: We carried out sequencing of parental genomes and offspring transcriptomes using next generation sequencing. We subsequently carried out genome scale identification of single nucleotide polymorphisms (SNPs) in two different ways using either individual genome mapping or joint genome mapping of the same breed parents that were used for the reciprocal crosses. Using parent-specific SNPs, allele-specifically expressed genes were analyzed. Results: Because of the low genome coverage (${\sim}4{\times}$) of the sequencing results, most SNPs were non-informative for parental lineage determination of the expressed alleles in the offspring and were thus excluded from our analysis. Consequently, 436 SNPs covering 336 genes were applicable to measure the imbalanced expression of paternal alleles in the offspring. By calculating the read ratios of parental alleles in the offspring, we identified seven genes showing allele-biased expression (p<0.05) including three previously reported and four newly identified genes in this study. Conclusion: The newly identified allele-specifically expressing genes in the neocortex of pigs should contribute to improving our knowledge on genomic imprinting in pigs. To our knowledge, this is the first study of allelic imbalance using high throughput analysis of both parental genomes and offspring transcriptomes of the reciprocal cross in outbred animals. Our study also showed the effect of the number of informative animals on the genome level investigation of allele-specific expression using RNA-seq analysis in livestock species.

• 한국융합학회논문지
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• 제12권9호
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• pp.229-238
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• 2021

본 연구의 목적은 상호동료 교수법을 적용한 핵심기본간호술 자율실습(투약단원을 중심으로)이 간호대학생의 학습에 미치는 영향을 심층적으로 이해하기 위함이다. 연구참여자는 간호학과 4학년 학생 15명이었으며, 심층면담을 통해 자료를 수집하였다. 수집된 자료를 분석한 결과, '학습동기 유발', '자기주도 학습', '성취도 향상', '학습요구 불충족'의 4개의 주제가 도출되었다. 상호동료 교수법을 적용한 핵심기본간호술 자율실습은 참여자들에게 편안한 환경과 자신감 향상으로 학습동기를 유발하고, 주도적인 사전학습 및 학습자의 언어로 학습할 기회를 얻는 긍정적인 경험이 있었다. 하지만, 추가적인 지식확장이 어렵고 충분하지 않은 학습요구로 불안감을 느끼는 경험도 있었다. 이에 상호동료 교수법을 자율실습에 적용할 때, 교수자는 학습자의 학습요구를 충분히 만족시키는 방안을 적용하면 효과적일 것으로 생각된다.

• 한국콘텐츠학회논문지
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• 제22권9호
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• pp.426-438
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• 2022

본 연구는 루게릭병 환자와 가족을 돕자고 호소하는 메시지를 대상으로 호혜적/공감적 소구의 상대적 효과를 탐색하였다. 이를 통하여 나눔 메시지의 전달에서 이성적으로 호소하는 방식인 호혜적 소구의 적용 범위를 살펴보고자 하였다. 공감적 관심 성향의 조절작용을 포함하였는데, 공감적 관심은 대표적인 이타적 성향이다. 온라인 실험 형태로 진행하였으며, 1단계에서 공감적 관심 성향을 측정하고, 대략 7일의 시간이 지난 후 2단계에서 호혜적/공감적으로 구분된 나눔 메시지를 보여주고 평가하도록 하였다. 불성실한 응답을 한 참가자를 제외하고 최종적으로 134명의 데이터를 분석하였다. 그 결과 공감적 소구의 상대적 우위가 일부 나타났지만, 호혜적/공감적 소구의 상대적 차이가 직접 나타난 경우는 주제 태도에 국한되었고, 상호작용의 결과에서 공감적 관심 성향이 높은 집단에서 호혜적 소구가 공감적 소구만큼 혹은 영향력이 더 큰 것으로 나타났다.

• 아동학회지
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• 제28권3호
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• pp.19-44
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• 2007

This study used the hypothetical path model to investigate individual traits(attachment, reciprocal relationship, and self-esteem), situational evaluation(justification, and intention) and jealousy level in adolescents. Subjects were 853 7th, 9th, 11th grade students in the city of Daegu. Results showed that scores of girls were higher than boys on self-reported and peer-reported jealousy level, attachment, reciprocal relationship, adaptive expression and non-adaptive expression. Scores of boys were higher than girls for self-esteem, justification. Self-reported jealousy level was affected by situation evaluation(justification and intention) and attachment. Peer-reported jealousy level was affected by reciprocal relationship. Jealousy expression modes were affected by self-reported jealousy level and attachment.

• 대한수학회보
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• 제52권2호
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• pp.377-394
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• 2015

In this paper, we generalize some results about Bertrand curves and Razzaboni surfaces in Euclidean 3-space to the case that the ambient space is Minkowski 3-space. Our discussion is divided into three different cases, i.e., the parent Bertrand curve being timelike, spacelike with timelike principal normal, and spacelike with spacelike principal normal. For each case, first we show that Razzaboni surfaces and their mates are related by a reciprocal transformation; then we give B$\ddot{a}$cklund transformations for Bertrand curves and for Razzaboni surfaces; finally we prove that the reciprocal and B$\ddot{a}$cklund transformations on Razzaboni surfaces commute.

• 한국자동차공학회논문집
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• 제2권2호
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• pp.59-72
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• 1994

For a panel contribution of the passenger vehicle compartment, a model was created for acoustic analysis of the passenger vehicle compartment and through the acoustic normal modal analysis, frequencies and mode shapes of the resonance modes were calculated. Also, the contribution analysis of each panel was executed using acoustic reciprocal theorem, and through this analysis, normalized responses at the particular point indicate the relative contribution of each panel for generating noise and vibration

• Journal of Yeungnam Medical Science
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• 제34권1호
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• pp.80-83
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• 2017

A number of research papers have reported more frequent occurrence of rheumatic/autoimmune disease among patients with hypogonadism or a chromosomal anomaly with potential X-chromosome defects. A 30-year-old female patient came to the hospital with a main cause of bilateral buttock pain, which began two years ago and worsened seven days ago. Ankylosing spondylitis with invasion of both sacral-iliac joints was observed. On magnetic resonance imaging, although the uterus was observed normally, an ovary was not observed. In a chromosome test, balanced reciprocal X-1 translocation of 46,X,t(X;1)(p10;q10) was diagnosed. Here, we report on the first case involving ankylosing spondylitis accompanied by balanced reciprocal X-1 translocation.