• Asian-Australasian Journal of Animal Sciences
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• v.27 no.12
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• pp.1749-1754
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• 2014

The current experiment was designed to evaluate the efficacy of adding the multi-enzyme mixture (Natuzyme) into layers' diets with different levels of energy and available phosphorus in relation to laying performance, egg qualities, blood cholesterol level, microflora and intestinal viscosity. Two hundred and fifty 43-wk-old Hy-Line commercial layers were divided into five groups with five replicates per group (10 birds per replicate) and fed one of five experimental diets. A corn and soybean meal-based control diet was formulated and used as a control diet. Two experimental control diets were formulated to reduce energy and crude protein contents (rE) or energy, crude protein and phosphorus contents (rEP). In addition, Natuzyme was added into either rE (rE-Natu500) or rEP (rEP-Natu500) diet to reach a concentration of 500 mg per kg of diet. The experiment lasted 8 weeks. There were no significant differences in feed intake, egg production, egg weight, egg qualities such as eggshell color or Haugh unit, total cholesterol, relative organ weights and cecal microflora profiles between any dietary treatments. Natu500 supplementation into the rE diet, but not rEP diet significantly increased egg mass and eggshell qualities such as strength and thickness, but it decreased cecal ammonia concentration and intestinal viscosity in laying hens. In conclusion, the present study shows that adding multiple enzyme preparation could improve performance of laying hens fed energy and protein restricted diets.

• Journal of Korea Foundry Society
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• v.15 no.3
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• pp.252-261
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• 1995

The purposes of this study were to investigate the microstructural changes in alloy ribbons of Al-Fe-Mo-Si quarternary system at $450{\sim}500^{\circ}C$, and to study the coarsening mechanism of fine precipitates. Using the hot stage in TEM, in situ microstructural changes in Al-4Fe-0.5Mo-1.5Si alloy ribbon and Al-8Fe-2Mo-1.5Si alloy ribbon have been examined successively up to 60 hours at $450^{\circ}C$ and $500^{\circ}C$. Cell structure in zone B of Al-4Fe-0.5Mo-1.5Si alloy ribbon was observed to collapse even in 10 minutes by in-situ heating at $450^{\circ}C$ and the size of precipitates in zone B increased twice in 60 hours. The precipitates in zone A of Al-4Fe-0.5Mo-1.5Si alloy ribbon showed slower coarsening rate than those in zone B by in-situ heating at $450^{\circ}C$. The precipitates in zone A of Al-8Fe-2Mo-1.5Si alloy ribbon increased 50% by in-situ heating at $500^{\circ}C$ in 50 hours compared to the initial precipitates while any microstructual change in zone B was not observed by in-situ heating at $500^{\circ}C$ up to 50 hours. Only the precipitates in zone A of Al-4Fe-0.5Mo-1.5Si alloy ribbon satisfied $r^3{\propto}t$ relationship of coarsening mechanism.

• Journal of the Korean Ceramic Society
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• v.41 no.1
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• pp.69-75
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• 2004

The degree of the indentation damage and strength degradation for 3Y-TZP ceramics and (Y,Nb)-TZP/$Al_2O_3$ dental implant composites was investigated under the Hertzian cyclic fatigue. Fatigue tests were conducted at contact loads of 500 to 3000 N and up to $10^6$ cycles in exact in vitro environments. At 500 N, no strength degradation and crack generation was observed up to $5{\times}10^5$ contact cycles. Fatigue properties of 3Y-TZP ceramics was superior to (Y,Nb)-TZP/ㅍ composites due to stress relief caused by the phase transformation from tettagonal to monoclinic phase. As contact load increased, the drastic reduction in strength was found when the damage transition from ring to radial crack occurred. The extent of strength degradation was more pronounced in vitro environments probably due to chemical corrosion of artificial saliva through cracks introduced during large numbers of contacts.

• Korean Journal of Plant Resources
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• v.15 no.3
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• pp.279-284
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• 2002

To establish the mass propagation method of Typha orientatis Presl, several factors influencing seed germination were investigated. The best seed germination of T. orientalis was achieved under the light and 25~3$0^{\circ}C$ temperature. GA$_3$ tended to enhance seed germination, and 500 mg.L$^{-1}$ GA$_3$ showed 90.7% germination, which was 1.2 times of control. Compared to control, BA treatment prohibit seed germination. Especially, seeds were not germinated under 500 mg.L$^{-1}$ BA treatment. In case of KNO$_3$ and Ca(NO$_3$)$_2$ treatment, the germination rate was decreased by all concentrations, except 100 mM Ca(NO$_3$)$_2$.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.17 no.12
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• pp.2914-2920
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• 2013

In this paper, we prepared the samples with the heat-treated substrate by means of co-evaporation method. The samples prepared with heat-treated substrate of $500^{\circ}C$showed the vacancy on the surface, and it could be prevented by Se ambient condition. The samples prepared with variable heat-treated substrates such as $430^{\circ}C$, $460^{\circ}C$, $480^{\circ}C$ and $500^{\circ}C$ showed the increase of grain resulted to the increase of the density. Based on the XRD analysis, the heat treatment could remove the Cu2Se phase of the samples, but it didn't affect the absorption index of the samples. We, therefore, conclude the absorption index is not affected by heat treatment and is controlled by the thickness of the sample.

• YAKHAK HOEJI
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• v.58 no.3
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• pp.181-189
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• 2014

The aim of this was to evaluate the effects of Rhus Verniciflua Stoke (RVS) extract powder on the endurance capacity for the forced swimming mice. Thirty mice were divided into 3 groups including negative control, 250 (RVS-250) and 500 (RVS-500) mg/kg RVS extract powder groups for 4-times swimming exercises. The swimming times to exhaustion in RVS-250 and RVS-500 mice were prolonged 1.6- and 2.0-fold at 4 weeks compared with negative control mice, respectively. Blood biochemical parameters for AST, ALT, T-CHO and TG were not significantly different between RVS fed or negative control mice. However, blood concentration of creatinine was significantly increased in RVS-250 mice, but not in RVS-500 mice. During the longer swimming exercise in RVS group, blood glucose and lactate levels were significantly decreased, but free fatty acid not changed. And also LDH levels were significantly decreased in RVS groups compared to negative control mice. Hepatic lipid peroxidation was not affected by RVS, but SOD and catalase activity were significantly increased in RVS groups. Interestingly, the levels of testosterone and free testosterone were significantly increased in RVS groups before swimming exercise, but they were not significantly changed among groups after swimming exercise. The present results suggest that RVS extract powders may enhance swimming exercise performance by recovering the exercise-fatigue via reduction of blood LDH activity and by burning blood glucose as an energy source. These results imply that RVS-produced testosterone may act as an energy buster to enhance physical activity.

• Journal of Korean Academy of Nursing
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• v.46 no.4
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• pp.490-500
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• 2016

Purpose: This study was conducted to develop assertiveness training applying Dongsasub training for junior nursing students, and to verify effectiveness of the training on assertiveness behavior, self-esteem, clinical practice stress, and clinical competence. Methods: The study design was a non-equivalent control group non-synchronized design. Participants were 63 nursing students in clinical training (31 students in the experimental group and 32 students in the control group). The assertiveness training applying Dongsasub training consisted of four sessions. Outcome variables included assertiveness behavior, self-esteem, clinical practice stress, and clinical competence. Data were analyzed using Chi-square, Fisher's exact test and independent samples t-test with SPSS/WIN 21.0. Results: Scores of assertiveness behavior (t=-2.49, p=.015), self-esteem (t=-4.80, p <.001) and clinical competence (t=-2.33, p=.023) were significantly higher and clinical practice stress (t=4.22, p <.001) was significantly lower in the experimental group compared to the control group. Conclusion: Results indicate that the assertiveness training applying Dongsasub training can be used as a nursing intervention to lower clinical practice stress and improve the clinical competence of nursing students.

• Korean journal of food and cookery science
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• v.26 no.1
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• pp.1-12
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• 2010

This study was conducted to investigate the effects of job embeddedness on job satisfaction, organizational commitment and turnover intention in the food and beverage division of hotels. In addition, this study sought to identify the effects of job satisfaction and organizational commitment on turnover intention. Based on the literature reviews, five hypotheses were tested: job embeddedness was positively related to job satisfaction and organizational commitment and negatively related to turnover intention and job satisfaction and organizational commitment were negatively related to turnover intention. The subjects evaluated in this study were employees of the food and beverage division of five or four stars hotels in Seoul. Five hundred questionnaires were distributed and 293 were collected from July 1, 2009 to August 31, 2009, using convenience sampling method. After removing useless questionnaires, a total of 250 questionnaires (five-stars hotel 177, four-stars hotel 73) were analyzed using the factor analysis, a reliability test, and structural equation modeling analysis. The results revealed that job embeddedness was positively related to job satisfaction (t=8.762), organizational commitment (t=5.364) and negatively related to turnover intention (t=-3.500). Therefore, hypothesis I, II and III were accepted. However, job satisfaction (t=-.933) and organizational commitment (t=-1.923) were not negatively related to turnover intention. Therefore, hypothesis IV and V were rejected.

• Korean Journal of Medicinal Crop Science
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• v.12 no.4
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• pp.315-320
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• 2004

The purpose of this research was to investigate the effect of Orostachys japonicus A. Berger (OJB) on the immune system. Administration of OJB (500 mg/kg) enhanced viability of splenocytes and thymocytes in BALB/c mice, and also OJB increased of splenic T lymphocytes, significantly, increased CD4 positive $T_H$ cells and CD8 positive Tc cells. OJB markedly, enhanced the production of ${\gamma}-interferon$ in mice serum. OJB accelerated the apoptosis of L1210 and U937 leukemia cells and increased the expression of apoptosis-related ICE, c-myc, p53 gene. These results suggest that OJB have an immuno-regulatory and anti-cancer activity.

• TTA Journal
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• s.134
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• pp.24-29
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• 2011

지난 1990년대에는 월드와이드웹 (WWW)이 화투였고, 2000년대에는 모바일 인터넷이 화두였다면, 2010년대는 모든 사물이 네트워크에 연결되는 Internet of Things(이하 IoT)의 세상이 될 것으로 전망되고 있다. 지난 2005년에 발간된 ITU 보고서에 따르면, IoT가 식별자(부착하는 사물)와 센서 및 무선 센서 네크워크(감지하는 사물), 임베디드 시스템(생각하는 사물), 나노공학(수축하는 사물) 분야의 기술 발전을 통하여 감각뿐 아니라 지능적 형태로 전 세계의 모든 사물 및 객체가 상호 연결될 것이라 주장하며, 이에 대한 준비와 대비가 필요하다고 언급한 바 있다. 또한, 본 보고서는 IoT 실현을 위한 가장 중요한 도전으로 표준화와 협력, 프라이버시, 사회 도덕적 이슈에 대한 철저한 대응이 될 것이라 직시한 바 있다. 이제 우리가 살아가는 세상은 또 다른 새로운 변화에 직면하고 있는 것이다. 현재 전 세계에는 15억 대의 PC와 10억 대의 휴대폰이 인터넷에 연결되어 있으며, 향후 2020년까지 약 500억 대에서 1,000억 대의 장치가 인터넷에 접속하는 IoT 세상으로 전환될 것으로 예측하고 있다. 더욱이, M2M 통신뿐만 아니라 객체 사이 통신까지 포함한다면 인터넷에 연결되는 잠재적 객체의 수는 100조 개에 달할 것이라고 한다. 최근 우리나라에서도 사물지능통신이란 용어가 자주 회자되고 있다. 사물지능통신을 광의의 의미에서 해석하면 IoT로 일컬을 수 있을 것이며, 다만, 협의의 의미로 해석한다면, M2M 통신을 지칭하는 것이 맞는 해석이라고 생각된다. 이에 본 특집에서는 사물지능통신 기술에 대한 현황 및 정책, 앞으로의 서비스 전망, 나아가 표준화 추진 동향 등에 대해 살펴보고 앞으로 다가올 미래 디지털 ICT 사회 변화를 조명해 보고자 한다.