• Journal of Satellite, Information and Communications
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• v.7 no.1
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• pp.7-12
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• 2012

In this paper, we proposed spectrum sensing using cooperative relay to solve problem of sensing performance degradation due to CPE (Customer-Primise equipments) which causes low SNR (signal-to-noise ratio) problem. In cooperative communication system, AF (amplify-and-forward) and DF (decoded-and-forward) is widely used for relay mechanism. Also, it is expected that cooperative relay scheme guarantees the high sensing performance by its diversity gain. Based on these backgrounds, in this paper, we apply to cooperative relay scheme to the CR (cognitive radio) system, and simulation results show comparison of the sensing performance between AF and DF.

• Nuclear Engineering and Technology
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• v.13 no.1
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• pp.12-21
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• 1981

An extension work of the previous paper on the rewetting velocity model is presented. Application of the rewetting velocity model presented elsewhere requires a priori values of ø. In the absence of ø values, film boiling heat transfer coefficient ( $h_{df}$ ) and fog-film length (ι) data are needed. To provide these informations, a modified Bromley's correlation is first derived and used to obtain $h_{df}$ values at higher pressure conditions. In addition, the analysis of the precooling parameters, such as ø and ι is further extended using much more expansive PWR FLECHT data. Thus, the applicable range of the rewetting velocity model is further expanded in this work.

• Journal of Microbiology and Biotechnology
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• v.26 no.9
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• pp.1527-1532
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• 2016

Strain SPF4211, having hyaluronidase (HAase) inhibition activity, was isolated from P. davidiana (Carriere) Franch fruit (PrDF) sugar extract. The phenotypic and biochemical properties based on 16S rDNA sequencing and an API 50 CHB kit suggested that the organism was B. subtilis. To optimize the HAase inhibition activity of PrDF extract by fermentation of strain SPF4211, a central composite design (CCD) was introduced based on three variables: concentration of PrDF extract (X₁: 1-5%), amount of starter culture (X₂: 1-5%), and fermentation time (X₃: 0-7 days). The experimental data were fitted with quadratic regression equations, and the accuracy of the equations was analyzed by ANOVA. The statistical model predicted the highest HAase inhibition activity of 37.936% under the optimal conditions of X₁ = 1%, X₂ = 2.53%, and X₃ = 7 days. The optimized conditions were validated by observation of an actual HAase inhibition activity of 38.367% from extract of PrDF fermented by SPF4211. These results agree well with the predicted model value.

• Journal of Animal Science and Technology
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• v.64 no.1
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• pp.123-134
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• 2022

Toll-like receptors (TLRs), as a part of innate immunity, plays an important role in detecting pathogenic molecular patterns (PAMPs) which are structural components or product of pathogens and initiate host defense systems or innate immunity. Precise negative feedback regulations of TLR signaling are important in maintaining homeostasis to prevent tissue damage by uncontrolled inflammation during innate immune responses. In this study, we identified and characterized the function of the pancreatic progenitor cell differentiation and proliferation factor (PPDPF) as a negative regulator for TLR signal-mediated inflammation in chicken. Bioinformatics analysis showed that the structure of chicken PPDPF evolutionarily conserved amino acid sequences with domains, i.e., SH3 binding sites and CDC-like kinase 2 (CLK2) binding sites, suggesting that relevant signaling pathways might contribute to suppression of inflammation. Our results showed that stimulation with polyinosinic:polycytidylic acids (Poly [I:C]), a synthetic agonist for TLR3 signaling, increased the mRNA expression of PPDPF in chicken fibroblasts DF-1 but not in chicken macrophage-like cells HD11. In addition, the expression of pro-inflammatory genes stimulated by Poly(I:C) were reduced in DF-1 cells which overexpress PPDPF. Future studies warrant to reveal the molecular mechanisms responsible for the anti-inflammatory capacity of PPDPF in chicken as well as a potential target for controlling viral resistance.

• Journal of agricultural medicine and community health
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• v.24 no.1
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• pp.79-89
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• 1999

The purpose of this study is to compare health status and activities for the pain and no-pain groups in the elderly. The study subjects included 189 elderly people(65 years and older) living in an urban area. They were surveyed at their homes through interview using a closed-ended questionnaire from Nov. 6th. to Nov. 16th. 1997. The instrument used in the study was selected after carefully reviewing pain-related articles and records well described the characteristics of the elderly. The data were analysed by using descriptive statistics and chi-square tests. The findings were as follows : Of the 189 subjects, 83.6% reported experiencing the pain for the last year. By the age, there were significant differences between the pain and no-pain group(${\chi}^2$=9.572, p=.023). The percentage of the pain complainers was the highest in 80 years and older(100.0%), followed by 70~74(89.1%), 75~79(81.3%), 65~69(76.8%) which presented crude increase according to age. By sex, men had lower pain prevalence(69.5%) than that of women(90.0%). The number of pain complainers was higher in women than men(${\chi}^2$=12.448, p=.023). There were significant differences between the pain and no-pain groups by spouse distribution(${\chi}^2$=10.736, p=.001), educational state(${\chi}^2$=13.020, p=.000), occupation(${\chi}^2$=18.807, p=.000). Pain prevalence in the subjects having no spouse(59.3%) was higher than those having spouse(40.7%), Illiteracy rate was higher in pain group(49.0%) than no-pain group(13.3%). The number of the subjects having occupation(full time or part time) was fewer in pain group than no-pain group. By health status, there were significant differences between two groups(${\chi}^2$=40.055, p=.000). : the pain group showed poor(61.4%), followed by moderate(22.1%), good(16.5%) while no-pain group showed good(64.5%), moderate(29.0%), poor(6.5%). By activities, there were significant differences between the pain and no-pain groups. The pain group was disturbed more severely than the no-pain group in movement(${\chi}^2$=57.829, p=.000), sleep(${\chi}^2$=12.785, p=.000), usual activities(${\chi}^2$=39.196, p=.000), receiving guests(${\chi}^2$=13.163, p=.000), and hobbies and recreation(${\chi}^2$=28.177, p=.000).

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.46 no.6
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• pp.94-102
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• 2009

In [1], the authors have proposed a novel scheme to achieve full diversity and to combat the time delays from each relay node, but decode-and-forward (DF) model operation mode puts more processing burden on the relay. In this paper, we not only extend their model into amplify and forward (AF) model proposed in [2],[3], but also propose an efficient decoding algorithm, which is able to order the joint channel coefficients of overall channel consisting of source-relay link and relay-destination link and cancels the previous decoded symbols at the next decoding procedure. The simulation results show that this algorithm efficiently improves its performance achieving 2-3dB gain compared to [1] in high SNR region and also useful to DF achieving more than 3dB gain compared to an original algorithm.

• Journal of Korean Academy of Nursing
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• v.14 no.2
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• pp.19-27
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• 1984

This study was carried out for the purpose of investigating the degree of importance in nursing activities for the quality of nursing, and was conducted with 72 nurses and 69 patients in Chungnam National University Hospital from January to April, 1984. The results are as follows; 1. The mean importants score in physical care activities of the patients (2.58) is higher than that of the nurses (2.48). There is not significant difference for the mean important score in physical care activities between the patients and nurses (t=0.637, df=139, p＞0.05). 2. The mean important score in psychological aspects of activities of the patients (2.94) is higher than that of the nurses (2.44). There is a significant difference for the mean important score in psychological aspects of activities between the patients and nurses (t=2.338, df= 139, p<0.05). 3. The mean important score in observation, recording and implementing medical care activities of the nurses (2.98) is higher than that of the patients (2.79) There is not significant difference for the mean important score in observation, recording and Implementing medical care activities between the patients and nurses (t=1.329, df=139, p> 0.05) 4. The mean important score in nursing management activities of the nurses (2.63) is higher than that of the patients (2.57). There is not significant difference for the mean important score in nursing management activities between the patients and nurses (t=1.329, df=139, p>0.05). 5. A number of items in nursing activities considered most important by nurses (Mean important score of 3.0 or above) were 12 items. The most importants item was“shift and exchange of information concerning patient”. 6. A number of items in nursing activities considered most important by patients (mean important score of 3.0 or above) were 14 items. The most important item was“Explain about diagnostic test ahead of time”. 7. A number of items in nursing activities considered least important by nurses and patients(Mean important score less than 1.9) were 5 items and 2 items, respectively. The least important item by nurses was“plan some diversion or recreation for patient”, and the least important item by patients was“Give a bed shampoo”.

• Korean Journal of Health Education and Promotion
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• v.14 no.1
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• pp.47-62
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• 1997

본 연구는 한국 보건전문가들의 보건행동을 조사하고, 보건행동간의 상호 관련 요인과 보건행동에 영향을 미치는 인구학적 요인을 분석하는데 그 목적이 있다. 본 연구 대상으로는 한국보건협회 산하의 8개의 보건 관련 학회 중에서 보건교육과 가장 관련이 있는 한국보건교육학회(212명)와 한국보건 간호학회 (124명) 회원 336명이 선정되었다. 본 연구의 도구는 미국에서 이미 실시된 여러 보건행동 연구를 기초로 하여 focus group discussion, back-translation, 전문가들의 panel discussion, 그리고 pilot test(사전조사)를 통하여 한국인의 보건행동 연구를 위해 타당하게 개발되었다. 본 연구를 위하여 1995년 약 두달동안(11월, 12월), 3차에 걸친 우편설문조사를 실시하여 64.3%의 응답회수율을 보였고, 응답자들의 보건행동을 분석하기 위해서 factor analysis(요인분석)와 ANOVA (변량분석) 방법을 사용하였다. 본 연구의 결과는 다음과 같다. 1. 조사응답자의 분포는 남자가 33.8%, 여자가 66.2%였고, 응답자의 80.3%가 석사 이상의 학위를 소유하고 있었다. 응답자들의 전공분야는 다양하였고, 그들 중에서 36.3%가 간호학, 24.4%가 공중보건학을 전공하였다. 응답자 중 과반수 이상이 학교에 근무하였고, 서울에 거주하였으며, 응답자의 평균 직장 근무연수는 14년 이였다. 2. 응답자들의 보건행동에 대한 요인분석 적용의 적합성을 사전검증하기 위하여 Bartlett’s Test of Sphericity (630.37, p〈.00)를 실시하였다. 응답자들의 보건행동을 요인분석한 결과, 17개의 보건행동으로 구성된 네가지 보건행동요인들이 추출되었다. 응답자들의 네가지 보건행동요인들은 다음과 같다: (1) 규칙적인 식사 및 과일 섭취 (2) 음주 및 흡연 (3) 외식,간식 및 카페인 음료 섭취 (4) 운동 및 휴식 3. 응답자들의 인구학적 요인과 네가지 보건행동요인들과의 관계를 분석한 결과, 성별(F=69.59, df=1,203, p〈.05), 교육정도(F=3.48, df=3,199, p〈.05) 그리고 직장(F=4.04, df=3,201, p〈.05)에 따라 음주 및 흡연 행동에 커다란 차이를 보였다. 또한 응답자의 직장 근무연수(F=2.39, df=5,185, p〈.05)에 따라 운동 및 휴식 행동에 커다란 차이를 보였다.

• Proceedings of the IEEK Conference
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• 2000.11a
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• pp.141-144
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• 2000

PRML (partial response maximum-likelihood) 과 FDTS/DF (fixed-delay tree search with decision feedback)는 기록 저장 시스템에서 준최적의 성능을 보임이 잘 알려져 있다. 그러나, 위와 같은 정보열 검출 기법은 피할 수 없는 복잡도 문제를 가지고 있다. 본 논문은 최소 run 길이 제한조건 d=2를 가진 광기록 채널을 위한 다양한 저복잡도 검출 기법을 다룬다. 우선, 결정 궤환 기법을 이용한 이산 정합 여파기 (discrete matched filter with decision feedback：DMF/DF)가 기존의 PRML로부터 유도된다. 유도된 시스템은 PRML보다 결정 궤환에 의한 성능 이득을 갖는다. 또한, 메트릭 계산을 사용하지 않는 저복잡도 FDTS/DF가 유도된다. 모의실험 결과에 의하면, 유도된 저복잡도 검출 기법들은 기록 밀도 S>=5.5에서 P(D)=1+D+D/sup 2/+D/sup 3/의 target을 갖는 PRML보다 우수한 성능을 보인다.

• The Transactions of the Korea Information Processing Society
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• v.2 no.1
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• pp.106-118
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• 1995

In this work, the optimized design methodology in high-level synthesis related with scheduling and hardware allocation is developed by simulated annealing technique effectively modified . Applying this method to digital filter design, the optimized tradeoff problem of speed and hardware costs in pipelined digital filter case and array digital filter case are investigated. While, it is confirmed that the suggested method gives the improved cost function value faster and can be used in complicated digital filter design.