• Journal of Magnetics
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• 제18권4호
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• pp.422-427
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• 2013

The aim of this study was to investigate effects of the number of acquisitions (NEX) on signal-to-noise (SNR) and artifacts in SENSE parallel imaging of magnetic resonance imaging (MRI). 3.0T MR System, 8 Channel sensitivity encoding (SENSE) head coils were used along with an in-vivo phantom. Reference sequence of 3D fast field echo (FFE) was consisted of NEX values of 2, 4, 6, 8, 10 and 12. The T2 turbo spin echo (TSE) sequence used for exams achieved SENSE factors of 1.2, 1.5, 1.8, 2.0, 2.2, 2.5, 2.8, 3.0, 3.2, 3.5, 3.8 and 4.0. Exams were conducted five times for each SENSE factor to measure signal intensity of the object, the posterior phase-encode direction and frequency direction. And SNR was calculated using mean values. SENSE artifacts were identified as background signal intensity in the phase-encoded direction using MRIcro. It was found that SNR increased but SENSE artifacts reduced with NEX of 4, 8 and 12 when the NEX increased in reference scan. It is therefore concluded that image quality can be improved with NEX of 4, 8 and 12 for reference scanning.

• 한국정보통신학회논문지
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• 제22권9호
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• pp.1243-1249
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• 2018

본 논문에서는 IEEE 802.15.4 슬롯 기반 CSMA/CA(Slotted Carrier Sense Multiple Access with Collision Avoidance) 네트워크에서 시스템 처리율 향상을 위해 동작 중인 단말 수 추정을 통한 백오프 기간 튜닝 기법을 제안한다. IEEE 802.15.4 슬롯 기반 CSMA/CA 네트워크에서는 각 단말이 채널을 항상 센싱하지는 않으므로, 제안하는 기법에서는 채널을 항상 센싱할 수 있는 PAN(Personal Area Network) 코디네이터를 사용하여 동작 중인 단말 수를 추정한다. 이 때, 실시간 단말 수 추정을 위해 단순 이동 평균 필터를 사용한다. PAN 코디네이터는 추정한 단말 수에 따라 튜닝한 최적의 백오프 기간을 비콘 프레임에 담아 PAN 코디네이터에 연결된 단말들에게 전달한다. 시뮬레이션을 통해 제안하는 기법의 단말 수 추정에 대한 성능과 시스템 처리율에 대한 성능을 평가한다. 시뮬레이션 결과를 통해 제안하는 기법이 IEEE 802.15.4 표준보다 더 높은 시스템 처리율을 얻을 수 있음을 보인다.

• 한국실내디자인학회논문집
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• 제22권6호
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• pp.241-250
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• 2013

In contemporary society, spa has become one of the important healing spaces. As the present urban life has been more and more complex and competitive, space of recreation and healing are dramatically increased in terms of its number as well as location. In the past, there were three kinds of spa visitors. The first was the people who visited spas for medical reasons. The second was the people who visited spas for leisure and refreshment. The third was for social gatherings like in the ancient Rome. In present time, these three reasons are mixed together. As the spa program became rich and various, visitors tends to seek an appropriate spa environment that suits their needs. This is the main background for contemporary spa designs. In any case, concept of healing has been always the core element in spa. Light and sense have vital role to make a unique spa design. This paper aims to study different light and sense applications in contemporary spa designs. Specific focus is to find how light and sense in spa designs act to create a healing environment. 4 spa projects built in Europe after 2000 were selected and were analyzed based on the 4 light and sense characteristics. In conclusion, case analysis was summarized to suggest future possibilities.

• 한국보육지원학회지
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• 제12권2호
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• pp.57-72
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• 2016

The purpose of this study was to examine the influence of teachers' vocational aptitude and sense of responsibility on their teaching efficacy in early childhood education and care. 259 teachers in ECEC were recruited from 19 daycare centers and the data were analyzed through frequency, percentage, Pearson's correlations, and stepwise regression using SPSS 18.0. The findings are as follows. First, teachers' teaching efficacy was significantly different according to their age, the number of years of teaching experiences, and education levels. Second, all degrees of teachers' vocational aptitude, sense of responsibility, and their teaching efficacy were higher than the median points. Second, teachers' efficacy relating with running class was affected most by the ability of safe management in vocational aptitude, and teaching methods in sense of responsibility. For teachers' efficacy relating to teaching, acceptability/sensitivity in vocational aptitude and motivation had the most impact. The implication was discussed in order to figure out the ways to increase teachers' efficacy.

• 한국수학교육학회지시리즈B:순수및응용수학
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• 제4권1호
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• pp.7-18
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• 1997

Consider an $r\;\times\;c$ contingency table under the full multinomial model in which each classification is ordered. The problem is to test the null hypothesis of independence. A number of tests have been proposed for this problem. In this article we show that all of these tests can be improved on in some sense for most cases. In fact the preceding tests sometimes are inadmissible in a strict sense. Furthermore, we show by example that in some cases improved tests can yield substantially improved power functions.

• 대한산업공학회지
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• 제16권1호
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• pp.59-65
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• 1990

In the design of AGVS (Automated Guided Vehicle Systems), one of the important problem is to determine the number of AGVs required to provide a given level of transport service. At present, there are two kind of methods to determine the number of AGVs, the one is to use the mathematical model, the other is to use the simulation technique. Among these, simulation based technique is more reliable than analytical method. In this sense, this paper intend to determine the optimal number of AGVs using personal computer simulation by SIMAN Ver.3.5.

• 한국조경학회지
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• 제40권5호
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• pp.119-128
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• 2012

본 연구에서는 도시텃밭 프로그램이 공동체의식에 미치는 효과를 규명하고자 서울의 3개 공공도시텃밭을 선정하여 설문조사를 실시하였다. 연구결과는 다음과 같다. 첫째, 텃밭프로그램이 참여자의 상호교제와 공동체의식에 미치는 영향이 다각도로 확인되었다. 지속적 프로그램이 있는 텃밭과 그렇지 못한 텃밭 사이에는 내부교제와 공동체의식에서 차이가 있었으며, 프로그램참여자가 비참여자에 비해 높은 수준의 텃밭활동, 내 외부교제 및 공동체의식을 보였고, 경로분석에서 도 프로그램참여가 공동체의식에 가장 큰 영향을 미치는 변수로 나타났다. 둘째, 자가점유, 거주기간, 참여인원이 공동체의식에 영향을 미치는데, 이는 거주기간이 긴 자가점유자, 특히 1인 및 노인 가구 등 사회적 소외계층을 대상으로 텃밭프로그램이 운영되어야 함을 시사한다. 셋째, 농업교육보다 지역사회와 연계된 다양한 문화 프로그램의 만족도가 높았다. 이 결과들은 도시텃밭의 공동체의식 형성효과를 높이기 위해서는 지속적이고 다양한 프로그램이 필요함을 보여준다.

• 화훼연구
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• 제17권3호
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• pp.179-184
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• 2009

페튜니아 5개 계통을 이면교배한 $F_1$ 10개 조합 및 양친에 대한 성 관련 형질인 초장, 초폭, 줄기길이, 줄기수, 절간장, 엽수 및 개회수 등의 형질에 대하여 상호관계 및 조합능력을 분석하였다. 초장은 초폭, 절간장 및 개회수 등의 형질들과, 엽수는 초폭, 줄기수 및 개회수의 형질들과 유의성이 인정되었으며, 특히 초폭과 절간장과의 사이에 고도로 유의한 정의 상관관계를 보였다. 일반조합능력(GCA)은 초장, 초폭, 줄기길이, 절간장, 줄기수, 엽수 및 개화수 등 모든 조사 형질에서 유의성이 인정되었고, 특수조합능력(SCA) 초폭, 줄기수, 엽수 및 개화수 등의 형질에서 유의성이 있었고, 일반조합능력효과가 특수조합능력효과보다 크게 작용하였다. 모본의 일반조합능력검정에서 D계통은 초 장, 초폭, 줄기길이, 줄기수, 엽수 및 개회수의 증가를 위해서, I계통은 초폭, 줄기길이 절간장에 대하여 일반 조합능력이 큰 것으로 나타났다. 특수조합능력 검정에서 초폭 증가에 뚜렷한 유의성을 보인 조합은 $D{\times}I$, $F{\times}I$와 $G{\times}I$조합이었고, 초폭, 절간장 및 개회수를 동시에 증가시키는데 유의성을 보인 조합은 $G{\times}I$조합이었다. 광의의 유전력은 7가지 형질 모두 크게 나타났고, 초폭과 줄기길이 및 절간장은 협의의 유전력도 높게 나타났다.

• 현장농수산연구지
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• 제3권1호
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• pp.85-93
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• 2001

페튜니아 6개 계통을 이면교배한 F₁ 15개 조합 및 양친에 대한 엽장, 엽폭, 분지수, 엽수, 엽면적, 생체중 및 건물중 등의 형질에 대하여 상호관계 및 조합능력을 분석하였다. 엽면적과 생체중은 엽장, 엽폭, 분지수 및 엽수 등 모든 형질들과 유의성이 인정되는 정의 상관관계를 보였고 건물중은 엽장, 엽폭 및 생체중과 고도의 정의 상관관계를 보였으나 엽수와 엽장과는 상관관계가 없었다. 조합능력의 분산은 일반조합능력이나 특수조합능력 모두 7가지 형질에서 유의성이 인정되었으며 특수조합능력의 분산구성분이 일반조합능력의 분산구성분 보다 크게 작용하여 이들 형질의 유전에는 비상가적 유전자 작용이 큰 것으로 나타났다. 모본의 일반조합능력에서 D와 G계통은 엽장증가에 대한 효과가 컸으며, C와 D계통은 분지수, 엽수 및 엽면적증가에 대하여 일반조합능력이 컸고, 생체중 및 건물중 증가를 위해서는 C, D와 G계통들이 일반조합능력이 큰 것으로 나타났다. D×E조합, D×G조합 및 E×G조합은 엽장, 엽폭, 분지수, 엽수, 엽면적, 생체중 및 건물중 등의 모든 조사형질에서 특수조합능력 효과가 높았다. 유전력은 7가지 형질 모두 광의의 유전력이 크게 나타났고 엽폭 및 건물중은 광의와 협의의 유전력 모두가 높게 나타났다.

• 한국치위생학회지
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• 제6권2호
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• pp.103-113
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• 2006

The purpose of this study was to examine and analyze motivation of entrance into the college, knowledge prior to the entrance, satisfaction with their major, and a sense of employment after graduation among students majoring in dental hygiene at some colleges and subdivide them by grades for comparative analysis to determine the progress of changes in general characteristics, department satisfaction, and a sense of employment among students majoring in dental hygiene for the recent three years and provide basic data for improving dental hygienic education. Questionnaires were distributed to 520 students majoring in dental hygiene at some college in South Chungcheong, South Jeolla, and North Jeolla Provinces, followed by explanation of the purport of the research and the content of the questionnaire; after completion, 513 copies were used for analysis with exception of 7 copies with insincere responses. The analysis of the data examined resulted in the following conclusions: First, Changes in Department Satisfaction among Students Majoring in Dental Hygiene As for motivation of entrance into a college, less and less students chose the department of dental hygiene through recommendation by parents or seniors while more and more students chose their major due to easy employment. Less and less students obtained information on the department from a college application guidebook while more and more students obtained it through Internet. There was also a gradual increase in prior knowledge about the department and in satisfaction with their major. More and more students had no will to change their course. Second, Changes in a Sense of Employment among Students Majoring in Dental Hygiene There was a gradual decrease in the number of students who would follow friends' or their own decision in selecting workplace but an increase in the number of those who would follow their professors' opinion. There was a gradual increase in the number of students who wanted to be employed in workplace with good social perception; many students wanted to be employed in a personal dental clinic, a general hospital, or a public health center; and more and more students also wanted to be employed in a school dental health center or to become a government official or an educator.