• 한국정보통신학회논문지
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• 제10권12호
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• pp.2289-2295
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• 2006

본 논문에서는 밀리미터파 대역의 신호 발생을 위한 헤테로다인 방식을 제안하고 실험적으로 분석하였다. 향후, 무선 이동통신, 초고속 광대역 통신망 등에 사용되어질 밀리 미터 파 신호는 전기적 요소의 한계로 광학적인 요소에 의해 신호를 생성하는 방법이 많이 연구되고 있다. 광학적 요소에 기술에 의한 소자기술 등이 발전되고 있다. 따라서 본 논문에서는 향후 밀리미터파 대역에서 사용되어질 LMDS(Local Multi-point Distribution Service) 등의 시 스템에서 수십기가 헤르츠급의 광원으로 응용 가능한 헤테로다인 방식을 이용한 밀리미터파 신호의 생성에 대한 이론적 방법 및 실험적 고찰을 통하여 검증하였다.

• 한국방사선학회논문지
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• 제12권4호
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• pp.505-510
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• 2018

의료영상의 프랙탈 부호화 방법은 영상을 반복 변환시스템인 IFS(iterated function system)를 구성해야하고, 이를 위해 영상영역을 레인지 영역으로 분할하고 각 레인지블록에 대해 탐색하게 될 도메인 블록에서 가장 닮은 최적의 블록을 찾는다. 이때, 결정되는 변환계수 값과 좌표의 정보를 프랙탈 계수로 전송한다. 본 연구에서는 이러한 프랙탈 계수들을 확률분포를 추출할 수 있는 양자화기를 통해 양자화 하여 비트를 할당하였다. IFS를 구성하는 부호화과정에서 가변크기 블록방법을 사용하여 부호화시간을 단축하고 압축률을 향상시키는 방법을 제시하였다. 추후 프랙탈 부호화과정에서 화질을 최상으로 유지하면서 부호화시간을 단축시키고 압축률을 높이는 연구가 더 진행되어야 할 것 으로 본다.

• 한국실내디자인학회논문집
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• 제17권6호
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• pp.170-177
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• 2008

This study starts off by stating that the lack of awareness in the importance of reasonable and systematized layout in management facility is essentially working against building a quality public library. And that there is a merit in studying the spatial elements, its density, amount of needed space, and the likes to efficiently deal with present workings of the library which are becoming more dynamic and complicated. This paper seeks to embark on this study and also to provide a foundational data for research on management facility of the public library. The paper bases its research on 10 public libraries which are located in Seoul City and in Gyeonggi province, and are built after the year 2000. The paper focuses on the spatial distribution by section and allotment of management facility space in the library. Consequently, to find solutions or to suggest improvements on problems encountered, the paper introduces Japan's cases (4 recently-built public libraries) as a foreign case study. With foregoing domestic and foreign library case analyses, and the survey results of managerial staffs' demands, the paper seeks to provide basic data about management facility space and its floorplan of the public library. The paper bases its research on pubic libraries' management facilities, and expects to contribute to the efficient building of the public library in the future.

• 경영과학
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• 제19권2호
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• pp.1-23
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• 2002

It has been considered as a means for sustaining a competitive advantage for companies to build and maintain long-term relationships with customers. It is without any doubt that many companies have tried to initiate Customer Relationship Management (CRM). For the effective management of customer relationships, it is critical that they acquire. share and use customer information and knowledge. In this paper, we deduced 9 important factors affecting the qualify of customer information and knowledge from the literature reviews on CRM, and developed the questionnaire to measure these factors. The factors are again categorized into organizational system, employees and IT. We analyzed data collected from 30 companies in service industries such as the finance. distribution and communication industries. The result of data analysis demonstrates that the employees' analytical shills and appraisal and reward systems are closely related to the quality of customer information, and analytical skills and IT support for communications with customers are associated with the quality of customer knowledge. implications of findings and future research directions are discussed.

• Advances in concrete construction
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• 제5권3호
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• pp.289-301
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• 2017

The synergistic interactions of supplementary cementitious materials (SCMs) with ordinary portland cement (OPC) in multi-blended systems could enhance the mechanical and durability properties of concrete and increase the amount of cement that can be replaced. In this study, the characteristics of the hydration products as well as paste microstructure of blended cement containing 20% coal fly ash, 10% rice hull ash and 10% sugar mill lime sludge in quaternary blended system was investigated. Portlandite content, hydration products, compressive strength, pore size distribution and microstructural architecture of hydrated blended cement pastes were examined. The quaternary blended cement paste showed lower compressive strength, reduced amount of Portlandite phases, and higher porosity compared to plain hardened cement paste. The interaction of SCMs with OPC influenced the hydration products, resulting to the formation of ettringite and monocarboaluminate phases. The blended cement paste also showed extensive calcium silicate hydrates and calcium aluminate silicate hydrates but unrefined compared to plain cement paste. In overall, the expected synergistic reaction was significantly hindered due to the low quality of supplementary cementitious materials used. Hence, pre-treatments of SCMs must be considered to enhance their reactivity as good quality SCMs can become limited in the future.

• Asian Journal of Business Environment
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• 제9권4호
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• pp.23-28
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• 2019

Purpose - With rapid population aging in Korea, changes in the population structure will result in a rise in the fiscal burden. This paper investigates the effects of population aging on fiscal spending based on Korea's province data and country panel data from the OECD. Research design, data, and methodology - We use province-level fiscal data from Local Finance Integrated Open System and the Korean Statistical Information Service and also collect country panel data from the OECD. To investigate the relationship between population aging and fiscal expenditures, our analysis uses the fixed effects model. Results - The empirical analysis based on Korean local finance and country panel data show that population aging has a positive impact on social welfare expenditures and it also has a positive impact on spending related to children and the elderly, implying that population aging may lead to an increase in fiscal spending via an increase in social welfare expenditures and spending related to children and the elderly. Conclusion - These empirical results suggest that countries like Korea that expect to experience rapid population aging need to pay more attention to prepare for the expected increase in age-related spending in the near future.

• 연구윤리
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• 제1권1호
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• pp.17-22
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• 2020

Purpose: This study is to develop managerial implications for JSAS for advancing to highly qualified journal and achieving its goals. Furthermore, the study sough to deduce implications of ethical issues of JSAS and to generate insights and future directions for JSAS management. Research design, data and methodology: This study employed a qualitative approach to review the current status of JSAS including its aims, managerial strategies and ethical systems. The study discussed ethical issues about fake journals and predatory journals to analyze the current states of JSAS's ethical system and to compare with each other. Results: Results indicated that JSAS has abided ethical requirements of common journals and established strict criteria, yet it should continuously observe blind peer-review systems to avoid unnecessary risks of being perceived as predatory journals. The rigorous ethical obedience will help JSAS to effectively perform its managerial strategies and to achieve its goals: Increasing submissions, inviting prestigious scholars to board member, and advance to high quality of journal. Conclusions: Continuous efforts of JSAS for ethical management is the most effective method to move to a high qualified international journal with reputation in academia. With the consideration of Korean journal society, ethical studies need to be further conducted.

• Journal of Multimedia Information System
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• 제5권3호
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• pp.195-200
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• 2018

Recently, as the sensor and big data analysis technology have been developed, there have been a lot of researches that analyze the purchase-related data such as the trajectory information and the stay time. Such purchase-related data is usefully used for the purchase pattern prediction and the purchase time prediction. Because it is difficult to find periodic patterns in large-scale human data, it is necessary to look at actual data sets, find various feature patterns, and then apply a machine learning algorithm appropriate to the pattern and purpose. Although existing papers have been used to analyze data using various machine learning methods, there is a lack of statistical analysis such as finding feature patterns before applying the machine learning algorithm. Therefore, we analyze the purchasing data of Songjeong Maeil Market, which is a data gathering place, and finds some characteristic patterns through statistical data analysis. Based on the results of 1, we derive meaningful conclusions by applying the machine learning algorithm and present future research directions. Through the data analysis, it was confirmed that the number of visits was different according to the regional characteristics around Songjeong Maeil Market, and the distribution of time spent by consumers could be grasped.

• The Journal of Asian Finance, Economics and Business
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• 제7권1호
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• pp.153-158
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• 2020

The study aims to identify the factors affecting employee loyalty in the case of small and medium enterprises (SMEs) in Tra Vinh province, Viet Nam and to find out critical factors affecting the loyalty of employees in SMEs. This is implemented with the method of collecting primary data of 320 employees working at SMEs in 5 districts including: Cau Ngang, Tra Cu, Chau Thanh, Cang Long, Tieu Can) and Tra Vinh City, Viet Nam. Using the multivariate regression method, the researchers have found 6 factors affecting employee loyalty: colleagues, leaders, job characteristics, remuneration policies, organizational culture, and working environment. Particularly, learning opportunities may not be not statistically significant for employees' loyalty towards small and medium-sized enterprises in Tra Vinh province. From the above research results, the authors have proposed implicational piolicies such as: focusing on colleague relationships, improving leadership of business owners, attaching importance to appropriate work arrangement, having appropriate remuneration policies for laborers, building effective organizational culture and working environment to improve employee loyalty at SMEs. From the above policy implications, helping business owners realize the aspirations of workers in small and medium-sized enterprises more closely in the future, in order to sustainably develop the business system in Vietnam.

• 산업경영시스템학회지
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• 제32권3호
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• pp.78-84
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• 2009

The purpose of this study was to compare gait patterns during pregnancy. Because of the changes in hormone levels and anatomical changes such as body mass, body-mass distribution, joint laxity, and musculotendinous strength that result from pregnancy, it was possible that there would be certain gait deviations associated with these changes. Three-dimensional gait analyses were performed from a self-selected pace, and six subjects(height : $163{\pm}5.3cm$, mass : $61.3{\pm}3.80kg$, $65.3{\pm}5.14kg$, $70.2{\pm}4.98kg$) participated in the three times(the early, middle and last years). 7 cameras(Proreflex MCU-240, Qualisys) and 2 force plates (Type 9286AA, Kistler) were used to acquire raw data. The parameters were calculated and analyzed with Visual-3D and Joint moments computed using inverse dynamics. In conclusion, pregnant women's gait patterns were changed during pregnancy period because pregnancy makes them physical changes. The main changes were joint moments and kinematic factors during pregnancy period. The pregnancy transformed normal gait pattern Into toe out position. Therefore, exercise programs to improve muscle activity were necessary where joint moments were small. The development of simulator should be studied for pregnant women's tailored shoes and accessories in future.