• 한국어병학회지
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• 제22권3호
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• pp.253-262
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• 2009

병든 넙치에서 분리한 Streptococcus parauberis (FP2284)를 스트레스 조건을 달리하여 넙치, Paralichthys olivaceus에 인위감염한 후 조직 내 생균수 변화 및 병리조직학적 변화를 분석하였다. 인위감염 실험은 건강한 넙치 (평균 어체 중 40.4 g)에 $2{\times}10^{8}$ CFU/fish 농도로 복강주사하고 스트레스를 주지 않거나 하루 2번, 2분간 Netting 스트레스를 처리하였다. 스트레스를 주지 않은 그룹과 Netting 스트레스를 준 그룹의 누적 폐사율은 각각 70% 및 95%로 나타났다. 인위감염 시킨 넙치에서는 체색흑화와 심장의 염증이 주요 임상소견으로 나타났으며, 심장에서는 주로 심외막염, 심근염 및 심근의 섬유화가 관찰되었다. 인위감염 후 심장 조직의 세균수 변화를 측정한 결과, 주사 후 3주째까지 심장 1 g당 $10^{4}$ CFU의 세균수가 유지되는 것으로 나타났다. 스트레스 조건하에서 심장에서의 병리조직학적 변화가 더 심한 것으로 나타났으며, 심장 조직내 세균의 점차적인 감소가 지연되는 것으로 나타났다.

• 한국콘텐츠학회논문지
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• 제15권11호
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• pp.238-249
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• 2015

본 연구는 자기위로능력이 청소년상담사의 직무환경 스트레스와 심리적 소진의 관계에 미치는 매개 효과를 분석하기 위해 수행되었다. 이를 위해 2015년 5월 5일 충남 청주에 소재한 한국교원대학교에서 개최된 청소년 상담 학술대회에 참가한 전국 공공기관 상담실, 학교상담실, 대학부설 상담실, 일반 기업상담실 등 청소년상담 현장에서 활동하는 경력이 풍부한 전문상담사와 수련감독 150명을 대상으로 설문조사를 실시했다. 최종 분석에는 113부의 설문지가 사용되었으며, SPSS v.20을 활용하여 분석한 결과는 다음과 같다. 첫째, 경력과 근무조건은 직무환경 스트레스에서 집단 간 차이를 보이지 않았다. 둘째, 직무환경 스트레스의 하위요인 중 '도전기회의 부족'과 '역할모호성'이 심리적 소진에 유의한 영향을 미쳤다. 셋째, 자기위로능력 중 '회복력'과 '자기노출'이 심리적 소진에 영향을 미쳤다. 넷째, 직무환경 스트레스와 심리적 소진의 관계에서 자기위로능력이 매개효과를 발휘하는 것으로 확인되었다. 이러한 연구 결과는 경력이 풍부한 청소년상 담사들은 물론 전반적인 상담사의 심리적 소진에 대처할 수 있는 대안 개발을 위한 유용한 정보로 활용될 수 있을 것으로 사료된다.

• 유변학
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• 제11권1호
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• pp.18-27
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• 1999

본 연구에서는 3차원 열성형 공정 알고리듬과 이에 membrane approximation을 도입한 근사적인 알고리듬을 개발하였고, 이 알고리듬을 이용하여 몇몇 열성형계에 대한 수치모사를 수행하여 그 결과를 비교 분석하였다. 3차원 알고리듬의 경우에는 구성한 유한요소 평형 방정식에 벌칙함수를 도입하여 비압축성 조건을 만족시켜 해를 얻었으며, membrane approximation을 도입한 알고리듬의 경우에는 두께 방향의 응력을 무시하여 구성한 방정식으로부터 해를 얻었다. 구성방정식은 2nd Piola-Kirchhoff 응력 텐서와 Cauchy-Green 변형 텐서를 사용하여 표현하였고 수지의 물질 모델식으로는 2항의 Mooney-Rivlin 모델을 사용하였으며, total Lagrangian coordinate를 도입하여 지배방정식을 유한요소화함으로써 알고리듬을 구성하였다. 대상계로 선정한 사각평판 수지의 자유 부풀림 거동과 금형이 있는 경우에서의 수지의 부풀림 거동을 3차원 알고리듬과 membrane approximation 알고리듬을 각각 이용하여 분석하였으며 3차원 알고리듬의 경우 clamping 부분의 경계조건을 달리하여 결과를 비교하였다. 금형이 있는 계에 대해서는 slip 경계조건과 no-slip 경계조건을 각각 부여하여 수치모사를 수행, 수지의 변형거동과 응력분포를 비교 분석하였으며, 두께를 달리 한 수지에 대해 두께 방향의 응력을 비교 분석함으로써 membrane approximation 알고리듬의 한계에 대하여 논하였다. 한편 수지 온도 변화에 따른 성형품의 두께 분포의 변화를 살펴보기 위하여 ABS 수지를 대상으로 하여 $137.8^{\circ}C$에서 $171.1^{\circ}C$사이의 온도에서 수행한 인장실험 데이터를 수치모사에 사용하였다. 그 결과 수지의 온도가 높을수록 두께의 표준편차가감소하여 균일한 두께 분포를 얻을 수 있음을 확인하였고 이는 수지의 흐름성이 증가함으로써 나타나는 현상으로 해석할 수 있다.

• 벤처혁신연구
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• 제3권1호
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• pp.143-163
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• 2020

본 연구는 성공적인 경영성과를 창출할 수 있는 소공인 CEO의 특성을 파악하여 실증적으로 분석하고, 이를 분석하는 과정에서 지식경영의 매개적 역할에 주목하여 지식경영이 어떤 역할을 하는지 파악하기 위한 목적으로 수행되었다. 소공인이 성공적인 경영성과를 창출하기 위해 소공인CEO의 대인유연성과 스트레스 내성이 직접적으로 경영성과에 미치는 영향을 규명하고, 이에 더 나아가 도전정신과 글로벌 역량이 지식경영을 매개로 경영성과에 미치는 영향을 검정하고자 하였으며, 선행연구를 통해 연구모형을 도출하고, 소공인 CEO를 대상으로 실증조사를 통해서 다음과 같은 결과를 도출하였다. 첫째, 소공인의 글로벌 역량이 경영성과에 직접적인 영향을 미치는 것으로 분석되었다. 둘째, 소공인의 스트레스 내성이 경영성과에 직접적인 영향을 미치는 것으로 분석되었다. 셋째, 소공인의 도전정신이 경영성과에 미치는 정(+)의 영향은 지식경영에 의해 완전 매개되는 것으로 나타났으며, 넷째, 소공인의 대인 유연성이 경영성과에 미치는 정(+)의 영향은 지식경영에 의해 부분 매개되었다. 이러한 연구결과는 기술 집약형의 소공인 업체가 적은자원을 투입하고도 스스로 활성화가 가능한 지식생태계를 구축하여 경영의 성공확률을 높일 수 있음을 시사하고 있다. 풍부한 지식경영의 노하우를 보유한 소공인이 지적자산의 가치를 이해하고, 이렇게 얻어진 지식을 어떻게 보다 효과적으로 시장가치로 전환 할 수 있을지 고민하며, 그 것이 성공적인 기업성과를 창출하는데 얼마나 중요한지를 보여주고 있다. 지식을 효과적으로 사용하기 위해 지식경영에 기술을 통합하는 최선의 방법과 소공인 CEO가 지식경영에서 얻어진 경험, 직감, 신념 등의 가치가 성공적으로 경쟁 우위를 확보하거나 유지할 수 있는 조건으로 어떻게 탄생할 것인가를 주목하고 인식하여 의지를 다져야 함을 시사하고 있다.

• 대한간호학회지
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• 제27권3호
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• pp.541-549
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• 1997

This study was done to describe health promoting lifestyle and determine affecting factors in elderly based on the Heath Promotion Model by Pender. Cognitive-perceptual factors that were included in this study were self-efficacy and hardiness. Modifying factors were demographic characteristics (sex, age, partner, previous illness, education level. income and religion). The specific purpose of this study was to examine the relationships of self-efficacy, hardiness and the demographic chasteristics to health promoting lifestyle and to determine causal factors affecting the elderly. The subjects were a volunteer sample of 98 elderly in one city in? The instruments for this study were Health Promoting Lifestyle Profile(47items, 4scale), Health Related Hardiness Scale(22i1ems, 6scale), general Self-Efficacy Scale(13i1ems, 5scale). Frequency, percentage, t-test, ANOVA, Pearson's correlation coefficient and Stepwise Multiple regression technique with SAS program were used to analyse the data. The Results of the study are as follows : 1) The average item score for the health promoting lifestyle was 2.63, the highest score on the subscales was interpersonal support (M=3.3), followed by self-actulization(M=2.9), nutrition(M=2.8), stress management(M=2.7), health responsibility(M=2.1) with the lowest bring exercise(M=2.0) 2) A significant difference between education level, income, religion and health promoting lifestyle were found. 3) All of the subscales on health promoting lifestyle were positively related to total hardiness (r=0.330, p<0.001). The hardiness subscale of control was positively related to self-actulization(r=0.276, p<0.01), and commitment was positively related to self-actualization(r=0.315, p<0.001), exercise /nutrition(r=0.245, p<0.01), interpersonal support(r=0.278, p<0.01), stress management(r=0.250, p<0.01). Challenge was positively related to self-actualization(r=0.315, p<0.001), exercise /nutrition(r=0.245, p<0.01). There was no significant correlation between self-efficacy and all of the subscales of health promoting lifestyle. Self-efficacy showed a significant correlation only with control(r=0.469, p<0.001), comittment(r=0.507, p<0.001), challenge (r=0.489, p< 0.001). 4) Comittment, self-efficacy and income explained 25.01% of the variance for the total health promoting lifestyle. The results of this study show that commitment, self efficacy and income predicted the health promoting lifestyle of the elderly. So health promoting programs that increase commitement and self-efficacy should be developed to promote a healthy lifestyle of the elderly, especially those who have low income.

• Asian-Australasian Journal of Animal Sciences
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• 제18권10호
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• pp.1445-1450
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• 2005

This experiment was conducted to evaluate the effect of feed withdrawal (F) and heat acclimatization (A) on malebroiler and -layer chickens responses to acute heat stress (AHS) at four weeks of age. Totals of ninety male chicks of broiler or layer type were randomly allocated into 30 pens of grower batteries with raised wire floors. Chicks were subjected to F and A three times a week through the first three weeks of age. At each time, feed withdrawal and heat acclimatization (T = $35^{\circ}C$) lasted for six and four hours, respectively. Feed consumption (FC), body weight (BW), and feed conversion ratio (FCR) were recorded weekly for broiler type chickens only. At four weeks of age, all groups of chickens were exposed to AHS (T = $39{\pm}1^{\circ}C$) for three hours. Before and after AHS challenge, body temperature (Tb), heterophil (H), and lymphocyte (L) counts were recorded, and H/L ratio was calculated. Antibody (Ab) response to sheep red blood cells (SRBC) was assessed from all treatments without being exposed to AHS. Group F of broiler-type chickens weighed less (p<0.05) compared to control group. Also, both A and F groups of broiler-type chickens consumed less (p<0.05) feed when compared to control group. Acute heat stress elevated Tb of all treatment groups, however the increase was more profound (p<0.001) in broiler chicks. Broiler chicks of both A and F groups showed a tendency to have higher (p = 0.08) Tb when compared to control group. Acute heat stress elevated (p<0.001) H/L ratio in both types of chickens. Broiler chicks maintained higher (p<0.001) H/L ratio. Both F and A groups reduced (p<0.01) the level of elevation in H/L ratio compared to control groups of both types of chickens. Neither A nor F group affected the Ab production in response to SRBC. However, there was a tendency towards higher Ab responses in F group when compared to other groups in both types of chickens. Results of the present study demonstrate that previous history of feed withdrawal or episodes of heat exposures improved chicks'physiological withstanding of AHS and a tendency to improved humoral immune response.

• Fisheries and Aquatic Sciences
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• 제18권3호
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• pp.273-281
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• 2015

The follistatin (FST) gene encodes a monomeric glycoprotein that plays a role in binding and inhibiting the functions of members of the transforming growth factor (TGF)-${\beta}$ superfamily. Thus, FST facilitates a wide variety of functions, ranging from muscle growth, to inflammation and immunity. In this study, we sought to characterize an FST counterpart, RbFST, which was identified from rock bream Oplegnathus fasciatus. The RbFST cDNA sequence (2,419 bp) contains a 933-bp open reading frame (ORF) that encodes a putative amino acid sequence for RbFST (35 kDa). The putative amino acid sequence contains a Kazal-type serine protease inhibitor domain (51-98 residues) and an EF-hand, calcium-binding domain (191-226 residues). Additionally, this sequence shares a high identity (98.7%) with the Siniperca chuatsi FST sequence, with which it also has the closest evolutionary relationship according to a phylogenetic study. Omnipresent distribution of RbFST transcripts were detected in the gill, liver, spleen, head kidney, kidney, skin, muscle, heart, brain, and intestine of healthy animals, with significantly higher expression levels in the heart, followed by the liver tissue. Under pathogenic stress caused by two bacterial pathogens, Streptococcus iniae and Edwardsiella tarda, RbFST transcription was found to be significantly up-regulated. Altogether, our findings suggest the putative role of RbFST in immune related responses against pathogenic infections, further prefiguring its significance in rock bream physiology.

• Geomechanics and Engineering
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• 제11권3호
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• pp.401-420
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• 2016

The stability of deep coal roadways with large sections and thick top coal is a typical challenge in many coal mines in China. The innovative Universal Discrete Element Code (UDEC) trigon block is adopted to create a numerical model based on a case study at the Dongtan coal mine in China to better understand the failure mechanism and stability control mechanism of this kind of roadway. The failure process of an unsupported roadway is simulated, and the results suggest that the deformation of the roof is more serious than that of the sides and floor, especially in the center of the roof. The radial stress that is released is more intense than the tangential stress, while a large zone of relaxation appears around the roadway. The failure process begins from partial failure at roadway corners, and then propagates deeper into the roof and sides, finally resulting in large deformation in the roadway. A combined support system is proposed to support roadways based on an analysis of the simulation results. The numerical simulation and field monitoring suggest that the availability of this support method is feasible both in theory and practice, which can provide helpful references for research on the failure mechanisms and scientific support designing of engineering in deep coal mines.

• Smart Structures and Systems
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• 제20권2호
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• pp.175-180
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• 2017

The load-carrying capacity and structural behavior of concrete-filled steel tube (CFST) structures is highly influenced by the grouting compactness in the steel tube. Due to the invisibility of the grout in the steel tube, monitoring of the grouting progress in such a structure is still a challenge. This paper develops an active sensing approach with combined piezoceramic-based smart aggregates (SA) and piezoceramic patches to monitor the grouting compactness of CFST bridge structure. A small-scale steel specimen was designed and fabricated to simulate CFST bridge structure in this research. Before casting, four SAs and two piezoceramic patches were installed in the pre-determined locations of the specimen. In the active sensing approach, selected SAs were utilized as actuators to generate designed stress waves, which were detected by other SAs or piezoceramic patch sensors. Since concrete functions as a wave conduit, the stress wave response can be only detected when the wave path between the actuator and the sensor is filled with concrete. For the sake of monitoring the grouting progress, the steel tube specimen was grouted in four stages, and each stage held three days for cement drying. Experimental results show that the received sensor signals in time domain clearly indicate the change of the signal amplitude before and after the wave path is filled with concrete. Further, a wavelet packet-based energy index matrix (WPEIM) was developed to compute signal energy of the received signals. The computed signal energies of the sensors shown in the WPEIM demonstrate the feasibility of the proposed method in the monitoring of the grouting progress.

• 한국수산과학회지
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• 제48권3호
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• pp.354-361
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• 2015

Mitochondrial heat shock protein 75 (mtHSP75) is a member of the HSP90 family and plays essential roles in refolding proteins of the mitochondrial matrix. Mitochondria provide energy in the form of ATP and generate reactive oxygen species (ROS). Heat shock proteins (HSPs) are activated in response to stress, and protect cells. In this study, we characterized the mtHSP75 of the big-belly seahorse Hippocampus abdominalis. The protein (BsmtHSP75) is encoded by an open reading frame (ORF) of 2,157 nucleotides, has 719 amino acids (aa), and is of molecular mass 82 kDa. BsmtHSP75 has two functional domains, a histidine kinase-like ATPase (HATPase_c) domain (123-276 aa) and an HSP90 family domain (302-718 aa). BsmtHSP75 was expressed in all tested tissues of healthy seahorses. The ovary contained the highest transcription level, followed (in order) by the blood, brain, and muscle. Pouch tissue showed the lowest expression level. The expression of BsmtHSP75 was significantly (P<0.05) up-regulated on viral or bacterial challenge, suggesting that BsmtHSP75 plays a role in the immune defense against bacterial and viral pathogens.