• Title/Summary/Keyword: 서비스의 품질

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Performance Analysis of Quasi-Orthogonal Space-Time Block Coded OFDM Systems (준직교 시공간 블록 부호화된 OFDM 시스템의 성능 분석)

  • Hwang, Kyu-Sang;Yi, Jong-Sik;Jong, Jae-Pil;Oh, Chang-Heon
    • Journal of Advanced Navigation Technology
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    • v.8 no.1
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    • pp.10-18
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    • 2004
  • As a technique for high-quality multimedia service in down-link, the transmit diversity schemes using a orthogonal space-time block codes were proposed. But if the number of transmit antenna is three or more, it was impossible to obtain full diversity gain because of the decline of spectral efficiency. Accordingly, the quasi-orthogonal space-time block code that not required a additional bandwidth was proposed. But using a space-time block codes, the transmit diversity schemes were verified over quasi-static and frequency non-selective channels. Therefore, in this paper, we analyze the performance of OFDM systems, which a frequency selective channel equalized a frequency non-selective channel, adapting the quasi-orthogonal space-time block code, and compare they to the conventional orthogonal space-time block coded OFDM systems.

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Adaptive Call Admission Control Based on Spectrum Holes Prediction in Cognitive Radio Networks (인지라디오망의 스펙트럼홀 예측기반 적응 호수락제어기법)

  • Lee, Jin-yi
    • Journal of Advanced Navigation Technology
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    • v.20 no.5
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    • pp.440-445
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    • 2016
  • There is a scheme where secondary users (SU) use predicted spectrum holes for primary users (PU) not to utilize for efficient utilization of the limited spectrum resources in cognitive radio networks. In this paper, we propose an adaptive call admission control framework that minimizes spectrum hopping call dropped probability (SHDP) for satisfying SU quality of service (QoS). The scheme is based on a call admission control (CAC), bandwidth prediction and adaptive bandwidth assignment. The prediction model predicts not only the number of spectrum holes, but requested bandwidth of SU spectrum hopping call, and then the CAC minimizes SHDP via an adaptive bandwidth assignment in resources not being enough for reservation. We bring Wiener prediction model to predict the resources. Simulations are conducted to compare the performance of proposed scheme with an existing, and show its ability of minimizing the SHDP.

A Study on the Application of QR Code through Case Study -Focused on Logistics and Distribution Sector- (사례 분석을 통한 QR 코드의 활용방안 연구 -물류.유통분야를 중심으로-)

  • Park, Eunji
    • Journal of Korea Port Economic Association
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    • v.29 no.4
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    • pp.247-264
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    • 2013
  • QR Code can save much more information than 1D Bar Code and encode various types of information. As it takes less general cost than high priced RFID, it can be recognized through smart-phone without any special facilities. Despite these strengths, QR Code is just used by general people for their daily life service, while 1D Bar Code is applied in all kinds of industry like sales, distribution, production management, quality management and so on. And RFID is also used in many industrial field like harbor and distribution area. The range of QR Code's usage is getting broad but still restrictive. So it is required to make new organized system. Therefore, this research suggests that Applying QR Code in the SCM. Connecting QR Code with SCM, it secures space for data's movement. And it helps not only rise the speed and accuracy of data flow but also reduce logistical cost.

Design of the LSF Parameter Quantizer for the Wideband Speech Codec (광대역 음성 부호화기용 선 스펙트럼 주파수 계수 양자화기 설계)

  • 지상현;강상원;윤병식
    • The Journal of the Acoustical Society of Korea
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    • v.20 no.4
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    • pp.29-34
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    • 2001
  • In this paper, we designed an LSF coefficient quantizer of the wideband speech codec that can produce high quality speech service. For the efficient LSF coefficient quantizer, the interframe correlation was used. Also we separately quantized the LSF coefficients with high and low interframe correlation. Predictive pyramid vector quantizer (PVQ) was used for quantizing the LSF coefficients with high interframe correlation, and PVQ was used for quantizing the LSF coefficients with low interframe correlation. Experiments show that the proposed UF quantizer can quantize LSF information in 40 bits/frame, with an average spectral distortion (SD) of 1 dB and less than 3.87% frames having SD greater than 2 dB.

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Indirect benefits of the introduction of Korean Spatial Information System (한국형 공간정보시스템 도입의 간접적 편익에 관한 분석)

  • Lee, Young-Sung;Kim, Kab-Sung;Jung, Hayoung;Kim, Jin
    • Journal of the Korean Regional Science Association
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    • v.33 no.2
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    • pp.39-46
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    • 2017
  • This study estimated indirect economic benefits of the introduction of Korean Spatial Information System. Korean academic society has been reluctant to consider indirect benefits as an item of benefits in cost-benefit analysis. Nevertheless, other countries including England recommend to consider some indirect benefits like option value as an important item of cost-benefit analysis, especially in the case of transportation projects. This study estimated indirect benefits of the introduction of Korean Spatial Information System using Contingent Valuation Methods: Indirect benefits of the project are so significant in terms of statistics and substantial in terms of magnitude that decision making can differ from the case without consideration of such indirect benefits.

A Priority Allocation Scheme Considering Virtual Machine Scheduling Delays in Xen Environments (Xen 환경에서 스케줄링 지연을 고려한 가상머신 우선순위 할당 기법)

  • Yang, Eun-Ji;Choi, Hyun-Sik;Han, Sae-Young;Park, Sung-Yong
    • Journal of KIISE:Computer Systems and Theory
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    • v.37 no.4
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    • pp.246-255
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    • 2010
  • There exist virtual machine scheduling delays in virtualized environment in which virtual machines share physical resources. Many resource management systems have been proposed to provide better application QoS through monitoring and analyzing application performance and resource utilization of virtual machines. However, those management systems don't consider virtual machine scheduling delays, result in incorrect application performance evaluation and QoS violations In this paper, we propose an application behavior analysis considering the scheduling delays, and a virtual machine priority allocation scheme based on the analysis to improve the application response time by minimizing the overall virtual machine scheduling delays.

The Influences of Social Intelligence on Cooperation and Individual Performance of Hotel Employees (호텔직원의 사회지능이 협력과 개인성과에 미치는 영향)

  • Lim, Ji-Eun
    • The Journal of the Korea Contents Association
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    • v.16 no.5
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    • pp.410-419
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    • 2016
  • The social intelligence, ability of social harmony and relationship was one of the key factor for hotel service quality. and then inquired the relationships among customer-facing employee's social intelligence of hotel, cooperation of employee, and individual performance. Through the theoretical consideration, concept of social intelligence was established, then we set up the hypothesis for causality relationship. The 201 customer-facing employee of a luxury hotel in Korea were analyzed. According to the results, social intelligence of customer-facing employee effects to cooperation of employee and individual performance positively as well. Cooperation of employee has been confirmed on a positive effect on individual performance. That is, social intelligence is social relationships to effectively building and maintaining a positive and essential skills to leading a substantial performance. Based on the empirical results, meanings, implications, and future research suggestions of social intelligence are discussed.

A Study on Measurement and Improvement of Service Quality using QFD in the Law Firm Industry (QFD를 이용한 기업 법무 서비스 품질 측정 및 개선에 관한 연구)

  • Pyo, In Soo;Lee, Jae Kwang
    • Knowledge Management Research
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    • v.17 no.2
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    • pp.1-26
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    • 2016
  • As entry barriers at the legal service market in Korea have been recently lifted, the legal service market has dramatically changed from a seller's market to a buyer's market. Externally, the Korean legal service market has been open to foreign law firms and internally, lawyers graduating from law schools have been increasing. In addition, as even the general public can easily access, through the official sites of government organizations, to the basic legal information such as laws and judicial precedents, the degree of information asymmetry has also decreased. These phenomena require the legal service industry to be a more client-oriented and more quality-oriented one. Having said that, legal service providers also need to continue to make strenuous efforts to measure and improve the service quality from the customers' perspective. Under these circumstances, this study introduced a certain type of model which may be of help of measuring and improving the quality of legal service of law firms, in particular, with a focus on those firms providing corporate legal service. This study used a Quality Function Deployment (QFD) in order to measure and thereby improve the quality of corporate legal service in the law firm industry. Above all, this study showed, by using SERVQUAL, each and every service attributes of quality measurement of the corporate legal service and also calculated the degree of importance of service quality at each process of providing corporate legal service. Next, this study introduced all supporting factors necessary for the provision of corporate legal service and calculated the degree of importance of each and every supporting factors in the service process. This study may be of help to provide the substantial and systematic approaches to the corporate legal service providers who would like to set up a certain methods of measuring and further improving the quality of corporate legal service from the customers' perspective.

The Relationship between Corporate Social Responsibilities and Financial Reporting Quality: Focusing on Distribution & Service Companies (사회적 공헌활동과 재무보고품질: 유통, 서비스 기업을 중심으로)

  • Chae, Soo-Joon;Ryu, Hae-Young
    • Journal of Distribution Science
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    • v.16 no.10
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    • pp.77-82
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    • 2018
  • Purpose - This paper examines the relationship between corporate social responsibility and financial reporting quality. Corporate social responsibility is a way for firms to take responsibility for the social and environmental impacts of their business operations. Corporate social responsibility is a broad concept that can take various forms depending on the firm and industry. Through corporate social responsibility programs, firms can benefit society. At the same time, firms improve their reputations by increasing engagement in corporate social responsibility activities. However, corporate social responsibility activities are not directly related to profitability, especially for distribution firms. Research design, data, and methodology - 229 distribution & service firm-years between 2011 and 2016 are used for the main analysis. In Korea, Korean Economic Justice Institute evaluates the ethical performance of Korean firms, and the institute annually discloses the scores of top firms. This study uses the KEJI Index scores to measure firm-level corporate social responsibility activities. Discretionary accruals are used as a proxy for financial reporting quality. Discretionary accruals can be used opportunistically, and thus distort the information in earnings. We extract financial data from the KIS Value database. Results - We find that distribution & service firms' engagement in corporate social responsibilities is positively related to their financial reporting quality. First, there is a negative correlation between implementation of corporate social responsibility activities and discretionary accruals. In addition, we find that the coefficient of CSR is significantly negative, supporting our prediction. The result is significant at the 1% level. Conclusions - We examine the relationship between corporate social responsibility activities of distribution firms and their financial reporting quality while most prior studies examine the engagement in corporate social responsibility activities of manufacturing firms. The results of this study show that distribution & service firms engaging in corporate social responsibility activities are likely to maintain high-quality financial reporting.

Factors Affecting Behavioral Intention to Use the Integrated Platform of Newspaper (신문사 통합형 플랫폼 사용의도에 영향을 미치는 요인)

  • Kim, Daewon;Kim, Min Sung;Kim, Seongcheol
    • The Journal of the Korea Contents Association
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    • v.15 no.4
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    • pp.122-138
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    • 2015
  • This research examines factors affecting behavioral intention to use integrated platform (IP), which is one of the business models regarding paid digital contents, based on extended United Theory of Acceptance and Use of Technology (UTAUT2). IP is a service which is designed to make digital content charged. It combines digitalized format of newspaper, premium news or behind news, and additional information. The results of this paper show that effort expectancy, social influence and hedonic motivation have positive relationship with behavioral intention to use IP (BI). Satisfaction with newspaper shows negative relationship with BI, which means that newspaper and IP can be replaced with each other. Newspaper subscribers tend to have higher BI than non-subscribers. Performance expectancy, gender, age, and satisfaction with website do not have significant effect on BI.