• 한국강구조학회 논문집
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• 제15권5호통권66호
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• pp.475-487
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• 2003

본 연구는 선형탄성 파괴역학적 방법을 사용하여 피로 손상을 평가할 수 있는 해석모델을 개발하는데 있다. 트럭 한 대가 교량상부를 통과할 때 부재에 발생하는 응력이력을 블록하중이라 정의하고 하중상호작용효과를 설명하는 균열닫힘 모델 이론을 적용한다. 블록하중에 대해 사하중 응력과 균열개구응력을 고려하여 응력범위빈도해석을 수행하였다. 여기서 구한 응력범위빈도분포에 확률적 방법을 적용하여 응력범위빈도분포의 확률분포 파라미타를 추 정하였다. 확률분포의 확률변수를 발생시키는 Monte Carlo Simulation 실행을 하여 파괴블럭수와 확률분포를 구한다. 이로부터 부재의 파로파괴가 발생하지 않는 피로신뢰성을 계산한다. 또한 파괴블럭수를 일평균 트럭교통량으로 나누면 예상잔존수명을 구할 수 있다. 제안된 피로신뢰성 해석모델을 사용하여 강상자형교 가로보와 수직보강개의 용접부에 피로신뢰성 해석을 수행 한 결과, 피크해석방법 결과와 잔존수명이 3.8% 정도 차이가 있었다. 이는 제안된 모델이 균열닫힘 현상이나 균열지연 형상을 고려하고 있음을 알 수 있었다.

• 한국컴퓨터그래픽스학회논문지
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• 제26권3호
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• pp.143-153
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• 2020

본 연구는 일상 속에서 스트레스를 관리할 수 있는 VR 컬러테라피 힐링콘텐츠 '노르니르'를 구현하고 이를 제안한다. '노르니르'는 CRR 분석법을 적용하여 사용자가 선택한 3가지 컬러에 따라 맞춤형 VR 컬러테라피 체험의 여정을 제공한다. 사용자는 해당 컬러 여정을 통해 자신에 대해 이해하고, 앞으로 실천할 목표를 다양한 색채 인터랙션과 자극으로 제공받으며, 스트레스 수준을 낮추는 힐링이 가능하도록 설계하였다. 구현된 결과를 바탕으로 콘텐츠 시연 후의 사용자의 스트레스 변화를 확인하기 위해 한국판 기분 상태 검사 'K-POMS'를 실험 참가자들을 대상으로 시연 전후에 실시하였다. 실험 결과 사용자들은 부정적 감정의 감소와 긍정적 감정의 증가를 뚜렷이 보였다. VR 기술을 활용하여 색채심리치료룰 접목하여 일상에서 잦은 스트레스에 노출되는 사용자들의 스트레스를 완화 시켜줄 수 있는 가능성을 제시하였다.

• Journal of Animal Science and Technology
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• 제61권6호
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• pp.333-339
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• 2019

The present study investigated the litter performance of multiparous sows had different feeding frequencies during summer season. A total of 60 crossbred multiparous sows was allotted to one of two treatments based on body weight (BW) according to a completely randomized design. Two different feeding frequencies based on NRC (National Research Council) were applied as conventional feeding (T1; 2 kg per meal at 06:00, 11:00, and 17:00) and night feeding (T2; 1.5 kg per meal at 06:00, 11:00, 17:00, and 2 kg at 22:00). Sows in T2 treatment had lower (p < 0.05) BW changes during lactation. The backfat thickness change of sows was decreased in T2 treatment during lactation (p < 0.05). The daily feed intake differed significantly between T1 and T2 with increased feed intake of the T2 group at 5.47 kg/d to 5.14 kg/d in the T1 group (p < 0.05). There was a significant difference in total weight of weaned piglets between T1 (70.50 kg) and T2 (74.34 kg). A greater total litter weight gain was observed in sows in T2 treatment. Night feeding is suggested for lactating sows with significant beneficial effects on litter growth during summer season.

• Animal Bioscience
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• 제36권3호
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• pp.521-528
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• 2023

Objective: This study investigated the effects of surgical castration on behavior, physiological and inflammatory indicators, and leukocyte cytokine mRNA levels in Korean cattle bull calves. Methods: Nineteen Korean cattle bull calves (average body weight, 254.5 kg; average age, 8.2 months) were divided into two treatment groups: control (n = 9) and castration (n = 10). Surgical castration was performed using Newberry knives and a Henderson castrating tool. Blood was obtained just before castration (0 h) and at 0.5 h, 6 h, 1 d, 3 d, 7 d, and 14 d after castration. Plasma cortisol (PC), saliva cortisol (SC), plasma substance P, and plasma haptoglobin concentrations, and the leucocyte mRNA levels of the interleukin-1-alpha (IL1A), interleukin-1-beta (IL1B), interleukin-1 receptor antagonist (IL1RN), and interleukin-6 (IL6) genes were analyzed. Results: Castration decreased (p<0.01) the average daily gain and gain/feed ratio. Castration reduced the time spent eating (p<0.001) and the eating frequency (p<0.01) and increased (p<0.001) the lying frequency. Castration temporarily increased (p<0.05) circulating PC and SC concentrations at 0.5 h after castration. Castration temporarily increased (p<0.05) plasma substance P concentrations at 1 d after castration. Castration increased (p<0.05) plasma haptoglobin concentrations at 1 and 3 d after castration. Castration increased (p<0.05) leukocyte mRNA levels of the IL1A, IL1B, IL1RN, and IL6 genes at 6 h after castration. Conclusion: Castration temporarily induced stress and expression of leucocyte inflammatory cytokine genes in Korean cattle bull calves.

• 여성건강간호학회지
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• 제18권3호
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• pp.223-235
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• 2012

Purpose: This study was designed to examine the relationships among daily hassles, social support, entrapment and mental health status in relation to gender in university students. Methods: Data were collected via a self- administered questionnaire from 118 male and 98 female college students in Kangwon province. Data were analyzed using SPSS/WIN 18.0 program for descriptive statistics, t-test, ANOVA, Pearson correlation, and stepwise multiple regression. Results: There were significant differences in daily hassles, entrapment and depression between male and female group. Also, there were significant relationship between entrapment and mental health status (i.e. depression, anxiety, hostility, somatization) in both groups. In male students, internal entrapment was the significant predictor of depression and anxiety, and external entrapment was the significant predictor of hostility and somatization whereas, in female students external entrapment was the significant predictor of depression, and internal entrapment was the significant predictor of anxiety, hostility and somatization. Conclusion: These results suggest that entrapment is an important factor for psychological maladaptation due to stressful life events. Therefore, strategies that reduce perception of entrapment according to gender should be developed for psychological adaptation.

• 대한수의학회지
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• 제42권1호
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• pp.65-71
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• 2002

We have utilized the PCR-RFLP method to detect the ryanodine receptor(RYR1) gene mutation and to estimate the genotype frequencies of the RYR1 gene in commercial crossbred pig population. The exon region(659bp) including point mutation(C ${\rightarrow}$T; Arg ${\rightarrow}$Cys) in the porcine ryanodine receptor gene, which is a causal mutation for PSS, was amplified by PCR and digested with Cfo I restriction enzyme. The RYR1 gene was classified into three genotypes by agarose gel electrophoresis. The normal homozygous(NN) individuals showed two DNA fragments consisted of 493 and 166bp. The mutant homozygous(nn) individuals showed only one DNA fragment of 659bp. Also, all three fragments(659, 493 and 166bp) were showed in heterozygous(Nn) carrier animals. The proportions of normal, carrier and PSS pigs within crossbred population of pigs were 81%, 15% and 4%, respectively. According to the results of analysis of variance for the association of genotypes of RYR1 of pigs at 30kg, day age at 90kg and average daily gains, the RYR1 nn genotype was very higher than RYR1 NN genotype for day age at 30kg with 5% level of significant difference, but no significant difference for association of any other genotypes with day age at 90kg and average daily gain in crossbred pigs. Therefore, DNA diagnosis by using PCR-RFLP analysis for the PSS gene was useful for large-scale screening of commercial pigs in the swine industry.

• Fisheries and Aquatic Sciences
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• 제19권10호
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• pp.44.1-44.8
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• 2016

Rockfish, Sebastes schlegelii (mean length $14.53{\pm}1.14cm$ and mean weight $38.36{\pm}3.45g$), were exposed for 4 weeks with the different levels of ammonia in the concentrations of 0, 0.1, 0.5, and 1.0 mg/L at 19 and $24^{\circ}C$. The indicators of growth performance such as daily length gain, daily weight gain, condition factor, and hematosomatic index were significantly reduced by the ammonia exposure and high temperature. The ammonia exposure induced a significant decrease in hematological parameters, such as red blood cell (RBC) count, white blood cell (WBC) count, hemoglobin (Hb), and hematocrit (Ht), whose trend was more remarkable at $24^{\circ}C$. Mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), and mean corpuscular hemoglobin concentration (MCHC) were also notably decreased by the ammonia exposure. Blood ammonia concentration was considerably increased by the ammonia concentration exposure. In the serum components, the glucose, glutamic oxalate transaminase (GOT), and glutamic pyruvate transaminase (GPT) were substantially increased by the ammonia exposure, whereas total protein was significantly decreased. But, the calcium and magnesium were not considerably changed.

• Human Ecology Research
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• 제60권2호
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• pp.243-256
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• 2022

Undergraduate freshmen are currently encountering numerous difficulties in adapting to college life due to the outbreak of the COVID-19 pandemic. Thus, several studies have underlined the need to develop interventions focused on undergraduate students' resilience during this situation. We adopted the service design method in identifying the difficulties faced by undergraduate freshmen during this pandemic, and also developed interventions for raising their resilience. The service design method is a person-centered approach which adopts the user's viewpoint in developing solutions, thereby enabling their requirements to be satisfied. Surveys and in-depth interviews revealed that undergraduate freshmen were experiencing psycho-emotional problems which were derived from schoolwork and college life. This is particularly the case with students who are experiencing greater levels of academic difficulty, and were insufficiently equipped with resources such as stress-coping strategies and social support. Four undergraduate freshmen were recruited online to test the effectiveness of a resource promotion program aimed at enhancing their resilience. This program has proved to be helpful in relieving daily/academic stress and in building relationships among freshmen, regarding which the participants showed a high level of satisfaction. The results were discussed by focusing on psycho-emotional difficulties and resources of college freshmen, as well as the effectiveness of the resource promotion program. Further research is required in order to verify the efficiency of the program and to confirm conclusions.

• 한국환경과학회지
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• 제31권3호
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• pp.237-245
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• 2022

The purpose of this study is to evaluate dogs' sociality toward human strangers in the absence of an owner by analyzing changes in dogs' behavior during a task of making eye contact with an experimenter to obtain snacks. A total of 17 dogs were divided into groups of high sociality (HS; n = 10, 4.4 ± 3.87 years) and low-sociality (LS; n = 7, 3.71 ± 2.06 years). A comparison of the average frequency of five behavioral types-fear-appeasement behaviors (P<0.001), sociability-related behaviors (P<0.001), stress-related behaviors (P<0.05), destruction (P < 0.001), and vocalization (P < 0.001)-between the groups showed a significant difference in all five categories. Together, these results suggest that dogs with high sociality are less exposed to various stresses and have a higher ability to adapt to new environments than dogs with low sociality. This can predict dogs' adaptability to a new environment and positive outcomes in their daily life with the owner.

• 디지털융복합연구
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• 제11권1호
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• pp.309-314
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• 2013

본 연구는 만성 심신기능저하가 건강관련 일상생활수행능력에 영향을 미치는 요인을 규명하기 위해 시도하였다. 자료수집은 2011년 6월 8일부터 2011년 7월 13일까지 서울에 소재한 종합병원에 내원한 148명을 대상으로 설문 및 면접조사를 하였다. 연구결과는 첫째, 운동습관 여부는 정기적으로 운동하는 경우가 환자군은 남성이 26.7%, 여성은 22.7%였으며, 위험비는 0.25 배로 나타났다. 반면 대조군의 경우 남성은 42.2%, 여성은 31.8%를 보였으며 위험비는 0.61 배이었다. 둘째, 남성의 경우 사회적 요인의 위험비는 45.18 배이었고(p=.04), 여성의 신체적인 요인은 237.1 배의 위험비를 보였다(p=.001). 이러한 결과를 토대로 만성 심신기능 저하를 예방하기 위해서는 건전한 생활리듬을 유지하고 면역력 증진하는 음식을 섭취하며 지속적인 운동 등을 통해 심신의 스트레스를 해소하는 것이 필요하다고 본다.