• 응용통계연구
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• 제10권1호
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• pp.105-119
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• 1997

일원배열형태의 가산 자료집합에서 각 군의 평균을 이용하여 처리효과를 비교할 수 있다. Barnwal과 Paul(1988)은 각 군의 산포모수가 같다는 가정 아래에서 처리에 따른 차이를 검정하는 우도검정통계량과 $C(\alpha)$ 통계량을 유도하였는데 본 연구에서는 이러한 가정이 만족되지 않아도 검정할 수 있도록 통계량을 일반화하였다. 또한 음이항분포 대신 Efron(1986)의 이중지수계 포아송 모형을 도입하여 새로운 통계량을 제시하였다. 모의실험을 통해 이중지수계 포아송 모형으로부터 유도된 $C(\alpha)$ 통계량이 어느 경우에나 적합함을 밝혔다.

• 조명전기설비학회논문지
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• 제20권9호
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• pp.32-39
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• 2006

In this paper, an iterative subspace-based calibration algorithm for a CDMA-based antenna array in the presence of unknown gain and phase error is presented. The algorithm does not depend on the array geometry and does not require a prior knowledge of the Directions Of Arrival (DOA) of the signals. The method requires the code sequence of a reference user only. The proposed algorithm is based on the subspace method and root finding approach, and it provides estimates of the calibration vector, the DOA and the channel impulse response, by using the code sequence of a reference user. The performance of the proposed algorithm was investigated by means of computer simulations and was verified using field data measured through a custom-built W-CDMA test-bed. The data show that experimental results match well with the theoretical calibration algorithm. Also, teh study propose an efficient algorithm using the simulated annealing technique. This algorithm overcomes the requirement of initial guessing in the subspace-based approach.

• 한국고분자학회:학술대회논문집
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• 한국고분자학회 2006년도 IUPAC International Symposium on Advanced Polymers for Emerging Technologies
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• pp.169-169
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• 2006

Novel liquid crystalline malonic ester monomers were synthesized from malonyl dichloride and mesogenic alcohols as a photoresponsive group. The monomers were polymerized with aliphatic or aromatic dibromides in the presence of sodium hydride to give 8 kinds of novel poly(malonic esters) with two symmetrical azobenzene groups. We found that the resulting polymer films could be used as rewritable optical data storage (or holographic image) media through a photoisomerization of azobenzene group by Ar laser irradiation. The sensitivity of data recording was dependent not only on the thickness of the polymeric thin film but also on the intensity of laser beam.

• 한국정보처리학회:학술대회논문집
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• 한국정보처리학회 2023년도 춘계학술발표대회
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• pp.539-541
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• 2023

COVID-19 is a viral pandemic disease that spreads widely all around the world. The only way to identify COVID-19 patients at an early stage is to stop the spread of the virus. Different approaches are used to diagnose, such as RT-PCR, Chest X-rays, and CT images. However, these are time-consuming and require a specialized lab. Therefore, there is a need to develop a time-efficient diagnosis method to detect COVID-19 patients. The proposed machine learning (ML) approach predicts the presence of coronavirus based on clinical symptoms. The clinical dataset is collected from the Israeli Ministry of Health. We used different ML classifiers (i.e., XGB, DT, RF, and NB) to diagnose COVID-19. Later, classifiers are optimized with the Bayesian hyperparameter optimization approach to improve the performance. The optimized RF outperformed the others and achieved an accuracy of 97.62% on the testing data that help the early diagnosis of COVID-19 patients.

• 한국산학기술학회논문지
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• 제14권3호
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• pp.1320-1329
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• 2013

일반인 중 심정지를 목격할 가능성이 가장 높은 중년층 여성들을 대상으로 숫자를 세는 방법에 따른 가슴압박소생술의 질과 피로도를 비교하여 최초반응자로서의 역할을 위한 심폐소생술 교육 프로그램을 마련하는데 기초자료를 제공하고자 한다. 3시간의 기본인명구조술 교육을 실시한 후, 확률할당을 통해 45명씩 두 그룹으로 배정하였다. 가슴압박소생술 도중 큰소리로 숫자를 세는 그룹 A, 숫자를 세지 않는 그룹 B로 나누어 인체모형에 2분간의 연구를 진행 하였다. 두 그룹간 가슴압박의 질은 유의한 차이를 보이지 않으면서 가슴압박의 중단시간이 단축되었고, 시간의 경과에 따라 흉부압박의 깊이가 줄어드는 빈도 또한 의미 있게 낮았다. 또한 가슴압박소생술 후 본인이 느끼는 피로도 또한 의미 있게 낮았다.

• 복식문화연구
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• 제28권3호
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• pp.313-329
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• 2020

Social Network Services (SNS) have become a vital means of shopping, significantly influencing consumers' purchases of fashion products. The aim of this study was to identify bandwagon consumption among fashion consumers and to analyze the effects of bandwagon consumption on negative emotions, purchase discontinuation, and switching intention. A survey questionnaire was developed, and data were obtained from 285 female consumers in Korea aged in their 20s and 30s who had experienced guilt, regret, or disappointment after purchasing fashion products using SNS during the previous six months. The survey results indicated four different types of band- wagon consumption: intentional, impulsive, unintentional, and planned. The presence of negative emotions such as guilt, disappointment, and regret were affected by different types of bandwagon consumption. Intentional bandwagon consumption only affected guilt, while unintentional bandwagon consumption affected both guilt and disappointment. Impulsive bandwagon consumption affected guilt and regret; however, planned bandwagon consumption only affected regret. Furthermore, negative emotions affected purchase discontinuation and switching intention. Planned bandwagon con- sumption had an effect on both purchase discontinuation and switching intention, while both impulsive and unintentional bandwagon consumption influenced switching intention only. Intentional bandwagon consumption had no effect on either purchase discontinuation or switching intention. The results of this study indicate that SNS consumers' bandwagon consumption causes different negative emotions, purchase discontinuation, and switching intention.

• 생태와환경
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• 제41권4호
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• pp.423-430
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• 2008

As of September 2008,45 Automatic Water Quality Monitoring Systems (AWQMS) have been installed at different sites on the 4 rivers to detect early the presence of pollutants in water and to issue an alarm. We count the number of issuing alarms by AWQMS, however, we will find the alarm has hardly been issued. The reasons for the scarcity of alarm issue are extensively being examined. The National Institute of Environmental Research attributes wrong alarm criteria for each AWQMS station to one the reasons. In this study, a suggestion has been made to modify the current alarm criteria to correspond with characteristics of river water quality. The current system with only two criteria (low and high) should be replaced as four-criteria systems (low, medium, high, and severe) based on cases of other advanced countries and stream conditions of Korea. The highest value of data collected for 5 years was suggested as the alarm criteria for each parameter. Meanwhile the alarm criteria for VOCs, phenol and heavy metals were established as same as drinking water quality criteria.

• 지식경영연구
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• 제15권4호
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• pp.189-206
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• 2014

Knowledge management is considered an important factor for competitive advantage and sustainability for firms. As many knowledge management systems failed to achieve the desired results, enterprise social media (ESM) has received considerable attention as an alternative solution for knowledge sharing within a firm. This paper attempts to investigate the influence of various aspects of ESM on knowledge sharing. While previous literature mainly focused on structural aspects of ESM, this study focuses on social psychological aspects, such as social connectedness, social awareness, and social presence, along with reputational aspects (such as self-presentation). Further, in order to clarify knowledge sharing behavior, this study classifies knowledge sharing behavior into two categories, knowledge contribution and knowledge acquisition. The data used in this study was collected from 179 individuals who have experience in their own ESM. The results show that both social connectedness and self-presentation positively influence the two types of knowledge sharing behavior, i.e., acquisition and contribution. Meanwhile, social awareness turns out to be a significant determinant of knowledge contribution only. Contrary to our expectations, however, social presence does not significantly influence knowledge sharing behavior.

• 공업화학
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• 제16권1호
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• pp.21-27
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• 2005

In order to conduct research on oil originated in Mongolia for further application of petroleum not only as fuel but also as raw material for organic synthesis, we need to study the physical, chemical characteristics and individual, group hydrocarbon's compositions of main petroleum fractions. A number of studies and surveys on the physical and chemical characteristics, group hydrocarbon's composition of petroleum deposits in Zuun-Bayan, Sukhaibulag, Tsagaan Elst, Tamsagbulag have been carried out earlier through n-g-M, aniline point and dispersimetric methods successfully. Yet a detailed chromatographical and NMR spectroscopic study for the individual hydrocarbon's composition of Tamsagbulag oil main fractions has not been conducted. In the present study the results of GC analyses of gasoline fractions of wells 19-3, 19-13 and 19-10, Tamsagbulag (Eastern Mongolia) were presence. The gasoline fractions of given wells were characterized by the high concentration of paraffins and presence of trace amount of olefins. There were identified 69 paraffins, 45 naphthenes, 41 aromatics and 3 olefins in total 158 individual hydrocarbons from each samples of gasoline fraction. The first attempts to classify Tamsagbulag oil under the individual hydrocarbon's composition data were successfully conducted and the supposition of a genetic classification of given oil as "sapropelic" type was made.

• 지식경영연구
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• 제21권2호
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• pp.119-135
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• 2020

Owing to pandemic (COVID-19), the traditional face-to-face education method has been changed to the non-face-to-face real-time online education methods. Using a real time-based video conference system, synchronous education can be adopted by face-to-face class easily. Specially, it is very important to minimize the difference in learning effects between face-to-face and non-face-to-face in Entrepreneurship education. In this study, in order to derive the factors that affect the satisfaction of learners in synchronous online education, authors collected data from learners taking a synchronous entrepreneurship course. Through previous research, learned the reality of education and the composition of lessons. Spatiotemporal effectiveness, mentor ability, and educational environment influence learning satisfaction. PLS-SEM results revealed that it was confirmed that only spatiotemporal effects affect learner satisfaction. However, the education environment (fluent operation and convenience of function use of real-time based online conference system) effect teaching presence, class structure, and spatiotemporal effects. Through this research, we hope to provide theoretical and practical support for developing effective teacher activities, proper lesson structure, convenient function of the conference system, and learner-centered online learning environment when developing synchronous online classes.