• 한국정보통신학회논문지
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• 제12권7호
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• pp.1256-1262
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• 2008

이동 방송망에서 핸드오버는 단말의 이동성을 보장하는 매우 중요한 요소중의 하나이다. DVB-H (Digital Video Broadcasting for Handhold) 표준은 DVB-T(Digital Video Broadcasting - Terrestrial) 표준에 단말의 이동성을 향상시키기 위해 개발되었다. 본 논문에서는 DVB-H 네트워크에서 핸드오버 성능을 향상시키기 위하여 새로운 방식을 제안한다. 제안된 핸드오버는 두 가지 형태의 단말을 대상으로 하는데 하나는 GPS수신기를 탑재한 단말이며 다른 하나는 GPS없이 동작하는 단말이다. 본 논문에서는 첫 번째 단말에서의 핸드오버를 위해 논문[1]에서 제안된 CDT(Cell Description Table)을 개선하였으며 두 번째 단말의 경우 새롭게 제안된 HMT(Handover Map Table)에 기반하여 미리 정해진 핸드오버 영역을 추정하는 새로운 방법을 제안하였다. 제안된 핸드오버 방식에서는 RSSI(Received Signal Strength Indication)의 신호패턴을 이용하여 핸드오버 영역을 추정한다. 제안된 핸드오버 알고리즘을 이용하여 핸드오버 시 소요되는 시간 및 전력소모를 최소화 할 수 있으며 컴퓨터 시뮬레이션을 통해 이와 같은 핸드오버 알고리즘의 성능을 분석하였다.

• The Journal of Asian Finance, Economics and Business
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• 제8권7호
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• pp.591-601
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• 2021

This study examined the effect of branding capability on business performance moderated by learning capability. This study was conducted with small- and medium-sized enterprises (SMEs) of coffee cafes in the ex-Besuki region, East Java, Indonesia, covering four regencies located around coffee-producing areas with geographical indication (GI) certification. 150 managers of coffee cafe were sampled using the census technique. Data were collected by questionnaires distributed to the coffee cafe managers. The data were then analyzed by using simple regression analysis, Moderation Regression Analysis (MRA) and Moderated MultiGroup Analysis (MMA). The results showed that learning capability positively and significantly affect business performance, and learning capability moderated/enhanced the effect of branding capability on business performance. The findings of this study suggest that branding capability and learning capability play a crucial role in the performance of coffee cafe business especially in the dynamic environment. Coffee cafe managers need to take concrete steps to improve their branding capability and learning capability and they also need to improve their ability to interact with their environment and be committed in managing the coffee cafe. Therefore, it is imperative that the role of branding capability and learning capability be optimized in order to improve the business performance of the coffee cafe.

• 한국신뢰성학회지:신뢰성응용연구
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• 제16권2호
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• pp.78-89
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• 2016

Purpose: In this paper, we investigate whether the endeavors for Six Sigma quality management by a firm have positive effects on its financial performance and the length of Six Sigma implemented period affects its financial status. We find a relationship between Six Sigma implemented period and several financial performance index using a smoothing spline function. Methods: A smoothing spline function is used in order to analyze the relationship between efforts for quality management and financial performance. Specifically, the return on assets, return on equity, sales cost and business fee are investigated as dependent variables and the efforts for quality management as independent variable. Results: As a result of the analysis, the indication is that companies that put effects into the Six Sigma quality management have a positive result in its financial status. In detail, the efforts for Six Sigma quality management have positive effects on total asset turnover ratio and Six Sigma implemented period on net income to net sales ratio. Additionally, companies with longer (shorter) period of Six Sigma program have more (less) improvement in its financial status. Conclusion: It can be concluded that the company's efforts for quality management positively influence financial performance.

• International Journal of Internet, Broadcasting and Communication
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• 제11권1호
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• pp.27-38
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• 2019

Sensors collect information for Internet of Things (IoT)-based services. However, indoor construction sites have a poor communication environment and many interfering elements that make it difficult to collect sensor information. In this study, a network was constructed between a Bluetooth Low Energy (BLE)-based IoT device based on a serverless IoT framework and a router. This experimental environment was applied to large- and small-scale indoor construction sites. Experiments were performed to test the communication performance of BLE-based IoT devices and routers at indoor construction sites. An analysis of the received signal strength indication (RSSI) graph patterns collected from the communication between the BLE-based IoT devices and routers for different testbed site situation revealed areas with good communication performance and poor communication performance due to interfering factors. The results confirmed that structural components of the building as well as the materials, equipment, and temporary facilities used in indoor construction interfere with the communication performance. Construction project managers will require improved technical knowledge of IoT, such as optimizing the router placement and matching communication between the router and workers, to improve the communication performance for large-scale indoor construction.

• The Journal of Asian Finance, Economics and Business
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• 제8권10호
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• pp.285-295
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• 2021

This study estimates the influence of organizational-level factors on work motivation and job performance of middle managers of small and medium enterprises (SMEs) in Vietnam. A 5-point-Likert-scale structural questionnaire consisting of 36 observation variables was used to survey middle managers of Vietnamese SMEs. 425 out of 500 responses collected were valid for multivariate data analysis. The results of confirmatory factor analysis and structural equation modeling reveal three main findings. First, philosophy and policy, compensation and benefits, goal system, and leadership have positively significant impacts on the work motivation of middle managers under investigation. Second, there is a significantly positive influence of work motivation on job performance. However, there is no indication that growth opportunities, work environment, evaluation system have significant impacts on the work motivation of respondents. Based on the findings, the study suggests four recommendations for Vietnamese SMEs to improve motivation and job performance of middle managers, which are (1) ensuring the clarity and soundness of the organizational policies and philosophies, especially human resources policy that boosts employees' work motivation; (2) building a comprehensive compensation and benefit system to attract and retain talented employees; (3) developing a clear and adequate goal system; (4) enhancing top-level managers' leadership abilities.

• 한국주거학회논문집
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• 제12권4호
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• pp.227-230
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• 2001

The Sri Autobindo Learning Center(SALC) is sponsoring the development of a passive solar village in Creston, Colorado, Situated near the Sangre de Cristo mountains, Savitri Village will be one of several religious communities in the area. This village will incorporate 12 permanent residences and teaching and guest facilities for fifty to one hundred people. The purpose of this study is to evaluate the passive solar elements and performance of guest house at the Sri Autobindo Learning Center(SALC). To do this evaluation, the following tasks needed to be addressed. 1. the guest house design 2. the location of weather data 3. The determination of the building heating load As part of the evaluation process, guest house design will be modified and the building load and solar saving recalculated. This process will be completed until the building performance is deemed satisfactory. The conclusion is as follows; The high solar savings fraction predicted by SUNCODE should taken as an indication that further design changes would probably not be cost effective. But adding removal overhangs or other low costs measures to increase comfort in the summer appear to be appropriate.

• Structural Engineering and Mechanics
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• 제5권5호
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• pp.635-644
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• 1997

The paper reviews the implementation and evaluation of exact methods for the computation of transcendental structural eigenvalues, i.e., critical buckling loads and natural frequencies of undamped vibration, on multiple instruction, multiple data parallel computers with distributed memory. Coarse, medium and fine grain parallel methods are described with illustrative examples. The methods are compared and combined into hybrid methods whose performance can be predicted from that of the component methods individually. An indication is given of how performance indicators can be presented in a generic form rather than being specific to one particular parallel computer. Current extensions to permit parallel optimum design of structures are outlined.

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 1995년도 추계학술발표회논문집(1)
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• pp.197-202
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• 1995

When the process disturbance of nuclear power plant occurred, the operator should ensure plant safety, economy and identify the causes of disturbance. To accomplish these goals, operator should process a large amounts of information. Among these, alarms would be often in the operator's first indication of a plant state change or disturbance. To support limited information processing capability of operator, considerable works are under way to develop advanced alarm processing systems and to evaluate it. However, conventional evaluation method could provide just evaluation results but the design alternatives to enhance alarm system performance. To overcome problems associated with conventional evaluation methods of alarm system, signal detection theory(SDT) was introduced, and it was possible conclude that SDT could not only evaluate system but also suggest design alternatives for performance enhancement.

• 대한전자공학회논문지
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• 제9권5호
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• pp.34-42
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• 1972

전류잡음은 탄소피막고정저항기의 품질을 나타내는 중요한 척도이다. 저항체피막상의 결함은 전류밀도의 불균형을 초래하고 결과적으로 전류잡음의 기대를 유발한다. 전류잡음의 크기는 저항재의 고유한 성질과 저항체의 처리, 조립 및 외장 등에 의한 여러 요인에 의존하고 있으나 각종 수명시험결과 저항기의 전기적특성과 전류잡음문에는 명백한 관계가 성립하고 있다. 대표군의 저항기에 대한 전류잡음지수의 정규분포를 표시하는 parameter를 해석하면 제품의 품질관리와 생산의 균일성을 판단하는 지표로서 매우 유용한 수단이다.

• 대한안전경영과학회:학술대회논문집
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• 대한안전경영과학회 2010년도 춘계학술대회
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• pp.219-230
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• 2010

Remarkably improvements have occurred recently in the maintenance management of physical assets and productive systems, so that less wastages of energy and resources occur. The technology of maintenance is about finding and applying cost-effective ways of avoiding or overcoming performance deterioration. Maintenance is thus a vital support function in business, especially as increasingly large investments are being required in physical assets. TPM(Total Productive Maintenance) focuses on optimizing planning scheduling. Availability, performance and quality rate are other factors that affect productivity. Especially there are some losses that affect the overall equipment effectiveness(OEE). These losses lead to low values of OEE, which provides an indication of how effective the production precess is. This study explores the ways in which Korean small and medium manufacturing industries can improve OEE.