• 한국동물위생학회지
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• 제33권1호
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• pp.45-50
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• 2010

Mycoplasma gallisepticum (MG) is major cause of chronic respiratory disease in chickens. M. synoviae (MS) most frequently occurs a subclinical upper respiratory infection but may result in airsacculitis and synovitis in chickens and turkeys. Both mycoplasmas induce economic losses by triggering chronic respiratory signs, airsacculitis and decreased egg production. For prevention of the infections, live attenuated andinactivated vaccines are commercially used for prevention of MG but not MS in Korea. Serum plate agglutination (SPA) and enzyme-linked immunosorbent assay (ELISA) have been commonly used for serological diagnosis for MG and MS. Recently, it is believed that MS spread in chickens is very seriously in Korea and respiratory infection with MS causes substantial loss in poultry farms. In this study, we investigated the serological prevalence of MG and MS in unvaccinated chickens between 2008 and 2009. The overall seroprevalence of MG was 24% of 2,094 for individual chickens and 24% of 189 farms. The overall seroprevalence of MS was 36% in 2,095 chickens and 39% in 198 farms. The results show that seropositive ratio of MS is higher than MG. The geographical prevalence of MG has been estimated in following sequence; Gangwon, Jeolla, Gyeonggi, Gyeongsang, and Chungcheong. The geographical prevalence of MS has been estimated as follows; Gangwon, Gyeonggi, Gyeongsang, Chungcheong, and Jeolla. Seasonal seroprevalencewas also examined, and it found that seroprevalence in spring, fall and winter was higher than that in summer in MG, but not in MS. No significant difference was shown in seroprevalence according to breed. Future study about pathogenicity of MS isolates would be needed and economical losses by MS outbreaks should be analyzed. Moreover, we compared sero-positivity obtained with SPA and ELISA. The kappa value of MG between SPA and ELISA was 0.8061 and the kappa value of MS between SPA and ELISA was 0.7649.

• 항공우주시스템공학회지
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• 제11권2호
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• pp.30-34
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• 2017

본 고찰은 위성시스템을 구성하는 본체, 고해상도 카메라로 대표되는 주탑재체 및 과학임무용으로 사용되는 과학 목적 및 기술검증용 탑재체 중 본체와 주탑재체를 제외한 탑재체에 대한 제품보증 방안에 관한 것이다. 현재까지 우리나라는 위성 개발 프로그램을 통해 위성 본체 및 주탑재체에 대한 제품보증을 성공적으로 수행하여 왔다고 할 수 있다. 다만, 모든 위성 개발 프로그램에서 개발예산과 기간에 제한이 있음을 고려할 때, 본체나 주탑재체와 비교시 그 중요도가 상대적으로 낮다고 할 수 있는 과학 및 기술검증용 탑재체에 대한 적정한 제품보증 수준을 결정하는 것은 매우 중요하다. 본 고찰은 이러한 관점에서 과학 및 기술검증용 탑재체에 대한 제품보증 방향을 모색하기 위한 것이다.

• 한국통신학회논문지
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• 제33권12B호
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• pp.1066-1074
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• 2008

본 논문에서는 충돌이 잦은 무선 저속 Personal Area Network에서 펄스 (pulse) 신호를 이용한 효율적인 그룹폴링 알고리즘을 제안한다. 현재 IEEE 802.15.4 (LR-WPAN) 표준은 저속, 저가, 저 전력 소모를 목표로 한다. 하지만, 최근 LR-WPAN (Low Rate Wireless PAN)의 응용범위가 확대되고 이에 따라 잦은 충돌이 발생하는 상황 또한 늘어나고 있다. 여기서 충돌의 대부분은 '히든노드 문제'로 인하여 발생되고 이는 CSMA/CA 만으로 해결하기 어렵고 연속해서 일어날 경우 네트워크 성능을 크게 저하시킨다. 또한, 현재 히든노드 충돌에 관한 대부분의 연구는 연속된 충돌이 잦은 상황에서 많은 채널 낭비를 유발한다. 본 논문에서 제안한 알고리즘은 잦은 충돌 상황이 발생하였을 때 이미 그룹핑 되어 있는 PAN을 전제로 펄스신호를 이용하여 각 그룹에게 채널 할당과 순서를 정해주고 할당 받은 그룹의 노드들만 경쟁 시킨다. 이에 따라 데이터를 보내기 위해 경쟁하는 노드의 수가 현저히 줄어 연속된 충돌을 줄이고, 충돌로 인한 채널낭비와 낮은 데이터 전송률이 보다 향상되어, 잦은 충돌로 인한 네트워크의 손상을 막는다. 이러한 성능 향상을 NS-2 시뮬레이션을 통해 확인하였다.

• Journal of Electrical Engineering and Technology
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• 제13권4호
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• pp.1663-1672
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• 2018

In recent times, gas insulated medium voltage (MV) circuit breakers (CB) form a vital component in power system network, considering its advantages such as reduced size and safety margins. Gas insulation characteristics of circuit breakers are generally measured by lightning impulse (LI) test according to IEC standard 60060-1 as a factory routine test. Considering the environmental issues of $SF_6$ gas, many research works are being carried out towards the mixture of $SF_6$ gases for high voltage insulation applications. However, few reports are only available regarding the LI withstand and streamer propagation characteristics (at both positive and negative polarity of waveform) of $SF_6/N_2$ gas mixture insulated medium voltage circuit breakers. In this paper, positive and negative polarity LI tests are carried out on 22 kV medium voltage circuit breaker filled with $SF_6/N_2$ gas mixture at different gas pressures (1-5 bar) and at different gas mixture ratios. Important LI parameters such as breakdown voltage, streamer velocity, time to breakdown and acceleration voltage are evaluated with IEC standard LI ($1.2/50{\mu}s$) waveform. Weibull distribution analysis of LI breakdown voltage data is carried out and 50% probability breakdown voltage, scale parameter and shape parameter are evaluated. Results illustrate that the $25%SF_6+75%N_2$ gas filled insulation considerably enhances the LI withstand and breakdown strength of MV circuit breakers. LI breakdown voltage of circuit breaker under negative polarity shows higher value when compared with positive polarity. Results show that maintaining the gas pressure at 0.3 MPa (3 bar) with 10% $SF_6$ gas mixed with 90% $N_2$ will give optimum lighting impulse withstand performance of 22 kV MV circuit breaker.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2006년도 International Symposium on GPS/GNSS Vol.1
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• pp.141-144
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• 2006

The deviations in the injection orbital parameters, resulting from launcher dispersions, need to be estimated and used for autonomous satellite operations. For the proposed small satellite mission of the university there will be two GPS receivers onboard the satellite to provide the instantaneous orbital state to the onboard data handling system. In order to meet the power requirements, the satellite will be sun-tracking whenever there is no imaging operation. For imaging activities, the satellite will be maneuvered to nadir-pointing mode. Due to such different modes of orientation the geometry for the GPS receivers will not be favorable at all times and there will be instances of poor geometry resulting in no output from the GPS receivers. Onboard the satellite, the orbital information should be continuously available for autonomous switching on/off of various subsystems. The paper presents the strategies to make use of small arcs of data from GPS receivers to compute the mean orbital parameters and use the updated orbital parameters to calculate the position and velocity whenever the same is not available from GPS receiver. Thus the navigation message from the GPS receiver, namely the position vector in Earth-Centered-Earth-Fixed (ECEF) frame, is used as measurements. As for estimation, two techniques - (1) batch least squares method, and (2) Kalman Filter method are used for orbit estimation (in real time). The performance of the onboard orbit estimation has been assessed based on hardware based multi-channel GPS Signal simulator. The results indicate good converge even with short arcs of data as the GPS navigation data are generally very accurate and the data rate is also fast (typically 1Hz).

• 한국정보통신학회논문지
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• 제11권12호
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• pp.2413-2418
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• 2007

무선 센서 네트워크에서 효율적인 에너지 사용을 위하여 분산적(distributed)이며 지역적인(localized) 방법으로 가상 백본을 구성하는 것은 매우 중요한 연구 대상이다. 라우팅이나 메시지 broadcast와 같은 목적으로 센서 네트워크에서 가상 백본을 구성하기 위하여 연결 Dominating set이 주로 사용되고 있다. 네트워크의 전체 성능을 향상시키기 위하여 연결 Dominating set은 최대로 작은 수의 노드로 가상 백본을 구성는 동시에 각 노드들의 에너지 상태를 고려해야만 한다. 이 페이퍼에서는 현재 센서 네트워크를 구성하는데 가장 많이 논의되고 있는 IEEE 802.15.4를 기반으로 한 Zigbee 네트워크에서 differ time을 사용하여 효과적으로 에너지를 관리하며 가상 백본을 구성하는 프로토콜을 제안한다. 제안된 가상 백본 프로토콜의 효율성은 시뮬레이션 결과를 통해 증명한다.

• 대한한의학방제학회지
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• 제31권4호
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• pp.245-252
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• 2023

Objectives : The purpose of this study was to explore the compounds, targets and related diseases of garlic by the approaches of network pharmacology and bioinformatics in traditional chinese medicine. Methods : We investigated components and their target molecules of garlic using SymMap and TCMSP and they were compared with analysis platform. Results : 56 potential compounds were identified in garlic, 26 of which contained target information, and it was found that these 26 compounds and 154 targets interact with each other through a combination of 243 compounds. In addition, Apigenin was linked to the most targeted gene (78) in 26 compounds, followed by Kaempferol (61 genes), Nicotic Acid (14 genes), Geraniol (11 genes), Eee (10 genes), and Sobrol A (9 genes). Among 56 potential compounds, three compounds (Kaempferol, Dipterocarpol, and N-Methyl cytisine) corresponded to the active compound by screening criterion Absorption, Distribution, Metabolism, Excretion (ADME). In addition, 12 compounds in 56 potential compounds were associated with gastrointestinal (GI) motility disorder. Among them, Kaempferol was a compound that met the ADME parameters and the rest were potential compounds that did not meet. Also, Kaempferol was closely related to GI motility disorder, indicating that this Kaempferol could be a candidate for potential medical efficacy. Conclusions : It shows the relationship between the compound of garlic, an herbal supplement, and the biological process associated with GI motility disorder. These results are thought to help develop strategies for treating GI motility disorders.

• 한국의상디자인학회지
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• 제19권4호
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• pp.93-104
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• 2017

This study is a basic study to develop shoe last design technology to enhance and revitalize the competitiveness of the handmade shoes. In-depth interviews were conducted with four manufacturers in Seongsu-dong to identify the production status and design technology of shoe lasts. The result of the research is as follows. Firstly, shoe lasts for adults are produced at intervals of 5mm between 245mm-285mm for men's shoes, and between 220-260mm for women's shoes. The production rate of women's shoes was high in the order of general type, boot type, and sandal type while men's shoes mainly produce general type. Secondly, the master last size and ball girth rating for men's and women's shoes were analyzed to EE-EEE grade at 260mm and D grade at 235mm. The length of the master last for men's shoes is 276-290mm, the heel width is 60-65mm, the ball width is 88-90mm, the ball girth is 250mm, and the waist girth is 248mm. The length of the master shoe last for women's shoes is 236-245 mm, the heel width is 50-55mm, the ball width is 78-80mm, the ball girth is 211~213mm, and the waist girth is 213~215mm. Thirdly, the last grading deviation is 5mm in length, the heel width is 0.5mm, the ball girth is 3.5mm, and the ball with is 1.2mm. The ball girth dimensions of Oxford type, slip-on type, and sneakers type are made at 250mm, 248mm, and 245mm for men's shoes. For women's shoes, the ball girth dimensions of pump type, loafer & boot type, and sandal type are made at 211~213mm, 214~215mm, and 211mm. Fourthly, t+he construction of the automation system is insufficient and almost completely depends on manual production.

• 한국통신학회논문지
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• 제33권9B호
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• pp.751-759
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• 2008

캐리어 이더넷은 여러 개의 2계층 매트로 망을 연결하는 광대역 백본망이다. 백본망에서는 복수 개의 스패닝트리를 구성하는 다중 스패닝 트리 프로토콜(Multiple Spanning Tree Protocol : MSTP)을 사용하는데 최근에 간단하면서도 성능이 더 우수한 최단 경로 브리징(EEE802.1aq - Shortest Path Bridging : SPB)이 제안되었다. SPB는 목적지 노드 당 한 개씩 생성한 최단 경로 스패닝 트리를 따라서 프레임을 전송한다. 그러나 불행하게도 SPB는 목적지 노드마다 한 개의 경로만 설정하기 때문에 망의 상태 변화에 대처하기 위해서 라우팅 경로를 변경할 수 없다. 만일 목적지 노드별로 복수 개의 경로를 설정한다면 망의 상태에 적응하는 라우팅 방식을 구현할 수 있다. 본 논문은 이 철학을 적용한 라우팅 방식인 목적지 에지 노드 분할을 이용한 스패닝 트리(Edge Node Divided Spanning Tree : ENDIST)를 제안한다. ENDIST는 에지 노드를 연결된 링크의 수만큼의 서브 노드로 분할하고 각 서브 노드마다 SPB를 사용하여 스패닝 트리를 생성한 후에, 목적지 노드로 향하는 수 개의 라우팅 경로 중에서 한 개의 라우팅 경로를 망이나 노드의 상태에 따라 플로우 단위로 선택한다. 추가된 트래픽 엔지니어링 기법으로 우리는 백본망에서 지연 시간을 낮추고 처리율(throughput)을 향상시킬 수 있다. 시뮬레이션을 통해 우리는 최대 부하에서 ENDIST의 처리율이 STP(Spanning Tree Protocol)보다 약 3.4-5.8배, SPB보다 약 1.5-2.0배로 우수하게 동작함을 확인하였다. 특히, ENDIST의 처리율은 우리가 조사한 경우 중 절반에서 별도의 논문에서 이론적으로 계산한 한계치에 매우 근접함을 확인하였다. 이는 ENDIST가 2계층 라우팅의 성능을 획기적으로 향상시켜서 거의 완벽한 스패닝 트리 계열의 라우팅 방식이 되었음을 뜻한다.

• 한국보건간호학회지
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• 제17권2호
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• pp.317-332
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• 2003

This study attempts to investigate the relations between the types of communication, the job satisfaction. and the nursing performance of the staff nurses. The subjects of this study were the 114 nurses working in general wards, intensive care units, and the emergency rooms of the general hospital in Kyongbuk province. They were asked to answer the questionnaires as regards the types of communication and job satisfaction, and their performance of nursing, and these were evaluated by the head nurses, and their direct seniors. The data were collected for 10 days from the September 17 to 26, 2002. According to the purpose of the study, descriptive analysis, ANOVA. Pearson correlation coefficient, and stepwise multiple regression were applied for the data analysis using SPSS 10.0. The results are as follows : 1. The types of communication of staff nurses showed that the upward communication was $3.12\pm0.56$. the downward communication was $3.56\pm0.42$. the horizontal communication was $2.98\pm0.44$. and the informal communication was $2.59\pm0.49$. It showed that the most frequent communication was the downward communication. 2. In terms of the job satisfaction, there was significant difference according to the length of the period working for one ward (F=5.95, p=0.003), 3. The performance of nursing was significantly different according to the age (F=23.52, p=0.000), the working duration as a nurses (F=21.9, p=0.000), the types of nursing unit (F=5.33, p=0.002), and the working duration in present nursing unit (F=15.87, p=0.000). 4. In terms of communication type, the job satisfaction was associated with quality of the upward communication (F=6.23, p=0.003), the downward communication (F=5.78, p=0.004), and the horizontal communication (F=11.73, p=0.000) There were no association between the types of communication and the performance of nursing. 5. There was a positive correlation between the communication and the job satisfaction. And the downward communication (r=0.398) showed the greatest correlation with the job satisfaction. There was no statistically significant correlation between the communication and the performance of nursing. And the upward communication (r=-0.058) showed a negative, though not significant correlation with performance of nursing. 5. There was a positive correlation between the communication and the job satisfaction. And the downward communication (r=0.398) showed the greatest correlation with the job satisfaction. There was no statistically significant correlation between the communication and the performance of nursing. And the upward communication (r=-0.058) showed a negative. though not significant correlation with performance of nursing. 6. The stepwise multiple regression result showed that the downward communication accounts for $15.8\%$ (p=0,000) of the job satisfaction.