• 전자공학회논문지CI
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• 제45권5호
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• pp.125-133
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• 2008

본 논문은 다양한 서비스 클래스가 제공되는 BcN (Broadband convergence Network) 환경에서 상위 우선순위 서비스의 품질을 보장하기 위한 능동 큐 관리 메커니즘 (Active-WRED)을 제안한다. 네트워크 혼잡 상황에서 제안된 메커니즘은 상대적으로 낮은 우선순위를 갖는 서비스의 drop 확률을 증가시키고 이에 따라 상위 우선순위 서비스의 drop 확률을 감소시킴으로써 상위 우선순위 서비스에 대해 패킷 손실로부터 품질을 보장할 수 있다. 제안된 능동 큐 관리 메커니즘의 성능을 분석하기 위해 이산 시간 큐잉 시스템의 통계적 분석 방법을 도입하였다. 두 서비스 클래스 (GS: Guaranteed Service, BS: Best Effort Service)만을 고려하여 제안 방안의 성능 분석을 위해 MMBP-2 (two-state Markov-Modulated Bernoulli arrival Process) 트래픽 소스 모델과 2차 이산시간 Markov 체인을 도입하였다.

• 한국식품조리과학회지
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• 제25권3호
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• pp.306-316
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• 2009

The purpose of this study was to investigate the influence of service marketing mix on customers' perceptions of values at family restaurants in Seoul. Frequency analysis, ANOVA, reliability analysis, factor analysis, multi-regression analysis were employed to analyze the data. First, perceptions for items such as food (p<.001), price (p<.001), process (p<.001), and employees were significantly different with regard to monthly spending money, and food (p<.001), physical evidence (p<.001), and employees (p<.001) were also significantly different by partner. All of the mixes (food, price, place, employees p<.001; promotion, process, physical evidence p<.05) had positive influences on the customers' monetary and overall values. And the mixes of place p<.001; price and employees p<.01; and food, process and physical evidence p<.05 negatively affected non-monetary values, whereas promotion had a positive influence. As a result, we conclude that the service marketing mix is an efficient marketing tactic to remove intangible factors from restaurant businesses. Likewise it is highly recommended that food-service companies manage the marketing mix in a customerfriendly manner to minimize the negative characteristics of services toward customers, and to promote the customer appreciation of family restaurants.

• 한국항만경제학회지
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• 제21권3호
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• pp.259-270
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• 2005

This study applies the Analytic Hierarchy Process (AHP) to evaluate service quality of Third-Party Logistics (3PL) providers. For this, 3PL service quality is conceptualized and measured using SERVQUAL's five dimensions such as tangibles, reliability, responsiveness, assurance and empathy. Then, the AHP method is applied to determining the relative importance of five service quality dimensions and eventually selecting the best 3PL provider. Finally, this study conducts an empirical case study on four companies providing 3PL services in Korea to demonstrate the basic idea suggested in this paper. The results obtained in the present study indicate that responsiveness to customers is the most important factor perceived by 3PL customers and 3PL C is the best 3PL provider according to the overall service quality scores. In contrast to some previous researches, this study examined issues of service quality from the perspective of 3PL customers as opposed to the perspective of 3PL providers. In order for this study to be more complete, future research is needed in establishing a set of metrics to quantify each dimension of 3PL service quality proposed.

• 지식경영연구
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• 제20권3호
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• pp.39-47
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• 2019

Response surface methodology (RSM) is a group of statistical modeling and optimization methods to improve the quality of design systematically in the quality engineering field. Its final goal is to identify the optimal setting of input variables optimizing a response. RSM is a kind of knowledge management tool since it studies a manufacturing or service process and extracts an important knowledge about it. In a real problem of RSM, it is a quite frequent situation that considers multiple responses simultaneously. To date, many approaches are proposed for solving (i.e., optimizing) a multi-response problem: process capability function approach, desirability function approach, loss function approach, and so on. The process capability function approach first estimates the mean and standard deviation models of each response. Then, it derives an individual process capability function for each response. The overall process capability function is obtained by aggregating the individual process capability function. The optimal setting is given by maximizing the overall process capability function. The existing process capability function methods usually use the arithmetic mean or geometric mean as an aggregation operator. However, these operators do not guarantee the Pareto optimality of their solution. Moreover, they may bring out an unacceptable result in terms of individual process capability function values. In this paper, we propose a maximin-based process capability function method which uses a maximin criterion as an aggregation operator. The proposed method is illustrated through a well-known multiresponse problem.

• 대한산업공학회지
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• 제42권1호
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• pp.30-37
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• 2016

A multi-server queueing system with an infinite buffer and impatient customers is analyzed. The system operates in the finite state Markovian random environment. The number of available servers, the parameters of the batch Markovian arrival process, the rate of customers' service, and the impatience intensity depend on the current state of the random environment and immediately change their values at the moments of jumps of the random environment. Dynamics of the system is described by the multi-dimensional asymptotically quasi-Toeplitz Markov chain. The ergodicity condition is derived. The main performance measures of the system are calculated. Numerical results are presented.

• 한국콘텐츠학회논문지
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• 제10권4호
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• pp.91-97
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• 2010

Web 2.0 시대를 맞아 최근 웹상에는 소셜 미디어 서비스(Social Media Service)가 각광받고 있다. 환경적 변화에 맞춰 사용자의 요구를 충족시키는 소셜 미디어 서비스로써 합주서비스를 제공하고자 한다. 합주서비스는 MMMD(Multi Media Multi Device) 개념으로 음원을 제공하고자 한다. 즉, 합주곡을 하나의 재생장치를 통해 듣는 것이 아니라, 악기 별로 재생장치를 선택해 연주함으로써 오케스트라에서 음악을 감상하는 것 같은 실감을 부여할 수 있다. 목표를 충족시키기 위해서 합주곡을 구성하는 악기 별 음원을 분리하고 연주를 위해 필요한 음원을 추출하고 음원을 각 재생장치로 전달하는 작업을 AET Process로 정의하였다. 음원 간의 동기화를 제어하기 위해서 쉼표를 이용한 동기화 알고리즘을 제안하였다. AET Process와 쉼표를 이용한 동기화 처리 방법을 이용하여 사용자에게 실감 있는 합주 서비스를 제공할 수 있다.

• 디지털융복합연구
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• 제11권11호
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• pp.775-781
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• 2013

N-스크린은 단일 컨텐츠를 다중 디바이스에서 시간 공간의 제약 없이 제공 받을 수 있는 서비스이다. 네트워크가 달라지거나 디바이스가 달라질 경우 혹은 플랫폼이 달라지는 경우에도 적합한 인증을 거쳐 디바이스에 맞는 영상을 끊김 없이 보낸다. 이에 따라 발생하는 보안 위협 요소로는 사용자 인증에 대한 문제가 발생한다. 이에 본 논문에서는 N-스크린의 특성상 발생하는 다중 디바이스에서 사용 가능한 인증 시스템을 제안하고자 한다. 기존의 인증기법 중 가볍고 처리 절차가 간단한 인증기법인 준동형 암호 알고리즘을 사용하여 사용자 인증을 간소화하였고, DATA의 무결성을 보장하고자 하였다. 또한 다중 디바이스를 사용하는 N-스크린 서비스의 특성상 장비 변경에 따른 추가 인증을 간편하게 처리하고자 하였다. 제안한 인증 프로토콜에 대한 효율성과 안전성에 대한 검토 결과, 암호 알고리즘을 처리하는데 작은 저장 용량과 낮은 프로세서에도 동작하기 쉽기 때문에 다중 디바이스를 사용하는 데 안전하고 적합하였다.

• Journal of the Korean Data and Information Science Society
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• 제19권4호
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• pp.1255-1267
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• 2008

Evaluation indices for products or services are important to improve the internal process of the company and to compare those with competitive ones. The sigma level in Six Sigma management does important role to evaluate the core characteristic, CTQ(Critical To Quality), derived in the considered product/service or process. In this research, we propose an overall evaluation index for the product/service or process with multiple characteristics, in other words, multiple CTQs. The proposed overall evaluation index is useful for the cases that the single CTQ is not enough to evaluate the practical interests, for example, the final products and services with complex procedures and relatively large scaled processes. This approach is discussed with sigma level for applying Six Sigma Projects, however, it is applicable to indices based on proportion or percentage as well. The practical examples with a manufacturing process and a customer survey based on focus group interview are given for illustrations.

• 한국인터넷방송통신학회논문지
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• 제14권4호
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• pp.113-120
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• 2014

본 논문은 최근 각광을 받고 있는 차선 이탈 알림 서비스인 LDW(Lane Departure Warning)와 같은 안정성 서비스를 제공하기 위하여, 비대칭 멀티코어 플랫폼을 구성한다. 멀티코어 플랫폼은 고속 영상처리를 담당하는 고속영상 MCU(Micro Controller Unit) 코어와 안정적인 제어를 요하는 곳에 저속 제어 MCU코어를 사용하는 멀티코어 H/W 플랫폼상에 AUTOSAR S/W플랫폼을 포팅하고, AUTOSAR 개발방법론에 따른 MBD(Model Based Development) 기반 모델을 활용하여 LDW 소프트웨어 컴포넌트(SW-C)를 설계하고 동작을 검증한다. 또한 고속 영상 MCU와 저속 제어 MCU간에는 가상화 기법을 사용하지 않고 타이머 기반 공유 메모리를 이용한 폴링 기법의 IPC(Inter Processor Communication) 기능을 개발하고, 외부 타 ECU(Electronic Contol Unit)와의 CAN 통신기능을 개발하여 알람 신호, 차량 시뮬레이션 신호와 같은 제어 신호 송수신을 처리할 수 있도록 AUTOSAR S/W 플랫폼을 적용한다. 본 연구를 통하여 고속 및 저속 비대칭 멀티코어상에 AUTOSAR가 탑재된 ECU 기능 개발이 가능함을 확인함으로써, ADAS(Advanced Driver Assistance System)와 같은 다양한 응용 서비스들을 제공할 수 있게 되며, ISO 26262로 대변되는 차량 기능안정성 확보가 가능하게 된다.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제10권2호
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• pp.647-669
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• 2016

Multiple attribute for decision making including user preference will increase the complexity of route selection process. Various approaches have been proposed to solve the optimal route selection problem. In this paper, multi attribute decision making (MADM) algorithms such as Simple Additive Weighting (SAW), Weighted Product Method (WPM), Analytic Hierarchy Process (AHP) method and Total Order Preference by Similarity to the Ideal Solution (TOPSIS) methods have been proposed for acoustic signature based optimal route selection to facilitate user with better quality of service. The traffic density state conditions (very low, low, below medium, medium, above medium, high and very high) on the road segment is the occurrence and mixture weightings of traffic noise signals (Tyre, Engine, Air Turbulence, Exhaust, and Honks etc) is considered as one of the attribute in decision making process. The short-term spectral envelope features of the cumulative acoustic signals are extracted using Mel-Frequency Cepstral Coefficients (MFCC) and Adaptive Neuro-Fuzzy Classifier (ANFC) is used to model seven traffic density states. Simple point method and AHP has been used for calculation of weights of decision parameters. Numerical results show that WPM, AHP and TOPSIS provide similar performance.