• Title/Summary/Keyword: best-effort service

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B-ISDN Signalling Protocol for Internet-Based Service (인터넷 서비스를 위한 B-ISDN 신호 프로토콜의 표준화 동향)

  • Kim, J.Y.;Joo, S.S.
    • Electronics and Telecommunications Trends
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    • v.13 no.6 s.54
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    • pp.83-93
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    • 1998
  • Best effort 서비스 품질만 지원하는 현재의 인터넷에 음성, 오디오 그리고 영상 통신 응용 서비스와 같은 새로운 멀티미디어 응용 서비스를 사용하려는 요구가 확대됨에 따라서 멀티미디어 서비스를 제공할 수 있는 인터넷의 필요성이 증대하고 있다. 또한 이러한 멀티미디어 서비스를 제공하기 위하여 서비스 품질(QoS)을 보장할 수 있는 통신 방식과 대량의 트래픽을 효과적으로 전달할 수 있는 메커니즘이 필요하게 되었다. 비동기 전송방식(ATM)은 이러한 멀티미디어 서비스를 인터넷에서 제공할 수 있는 최적의 통신 방식으로 고려되고 있는데, 이것은 ATM의 장점인 고속의 스위칭 기술과 논리적으로 VPI/VCI를 다중화 하는 기법, 그리고 유연한 서비스 품질 관리가 가능하기 때문이다. 본 고에서는 ATM 망에서 인터넷 서비스를 지원하기 위하여 결성된 ITU-T SG11의 Coordination 그룹인 Signalling Support of Internet-Based Applications(SoI) 회의 결과를 중심으로 하며 SoI의 표준화 연구 목표, B-ISDN 신호 프로토콜을 이용한 Long-lived 세션과 QoS에 민감한 세션의 인터넷 트래픽에 대한 ATM 연결 설정 절차 및 인터넷 세션 정보의 전달 방법 그리고 인터넷 서비스를 위한 멀티캐스팅 방법에 대하여 기술한다. 본 고의 목적은 인터넷 서비스 및 프로토콜을 지원하기 위하여 확장이 필요한 B-ISDN 신호 프로토콜의 기능을 명확히 기술하기 위한 것이다.

A Study on the Production Process Management Support System for Smart Shipyard Based on Mobile (모바일 기반 스마트 조선소 생산 공정관리 지원 시스템에 관한 연구)

  • Park, Ju-Yong;Oh, Hyoung-Seok;Lee, Dong-Kun
    • Journal of Welding and Joining
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    • v.32 no.5
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    • pp.58-64
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    • 2014
  • The shipbuilding industry is facing the various problems of less demand and oversupply owing to the global economic crisis and the increase in shipbuilding countries. Shipyards of the industry are making effort to strengthen their ability to handle the crisis via a smartwork technology for flexible working environment. In this study, we developed a smartwork system that manages the information in shipbuilding process with mobile devices such as smart phones and tablet PCs. To successfully apply the developed smartwork system to shipyards, we analyzed several best practices and management tasks of the shipbuilding processes. The developed system was designed by CBD approach that is a branch of service-oriented software engineering for reusability and flexibility on the system. As it is designed considering the flexible working environment, it supports to increase their productivity by reducing the time required to carry out tasks and by increasing the mobility required to manage work performance in field of shipyards.

THE PROVISION OF QUALITY AND SAFE FOODS IN SCHOOL LUNCH PROGRAM THROUGH CENTRALIZED FOOD PRODUCTION TECHNOLOGIES

  • Clara, M.L.;Rdn, Pi-Ms
    • Proceedings of the KSCN Conference
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    • 1998.08a
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    • pp.21-30
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    • 1998
  • Sound nutrition is the basic foundation for the health of a population. Proper nutrition education through the school system can actualize the building of sound nutrition being provided at school lunch programs along with nutrition education can have far reaching impact to the health of the whole nation. In Hong Kong, the recent change over from a half day to full day school program signaled the need for a school lunch program. However, there has been no organized effort so far in Hong Kong to provide such service. School lunches are being provided by caterers who are more concerned about profits than food safetly. Alarming rates of food poisoning occurring recently in Taiwan school has further accentuated the importance of fool safety. With the advent of centralized food production technologies, Dietirians can apply their nutrition knowledge and integrate with food production processes such that safe, healthy and nutritious mcals can be produced in large quantities in a cost-effective manner serving he needs of the school children. This paper introduces the centralized food production concept, using some of the cool chill production centers for school lunch programs in the United States as examples to discuss how new technologies and management system can be integrated to yield the best outcome in food quality and safety.

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A Scheme to Support a Low-delay Multicast Service on Differentiated Services Network (차별화 서비스 망에서 low-delay 멀티캐스트 서비스 제공 방안)

  • 문영성;조승윤;정병철
    • Journal of Internet Computing and Services
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    • v.2 no.2
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    • pp.23-36
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    • 2001
  • To support real-time multicast, the existing DS network may use the EF PHB for transmission, However, because of the dynamic characteristics of the multicast flow and the features of the EF PHB. it is very difficult to make a provision of resources or to manage the network when EF multicast flows increase, Also, the existing LBE PHB can not guarantee the transmission delay bounds required for the real-time multicast traffic, In this paper. a new concept of PHB. namely, low-delay multicast PHB, that may guarantee approximately the per-hop delay is proposed, For the low-delay multicast PHB, router architectures are devised, The queue management algorithm on a low-delay multicast queue and a scheduling method are also devised. This new architecture of the LDM AF class is simple to be implemented.

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Performance Evaluation of Diffserv Model for Providing QoS in Mobile IPv6 Networks (Mobile IPv6망에서 QoS 제공을 위한 Diffserv 모델의 성능 평가)

  • Kim, Mi-Sun;Mun, Young-Song
    • Journal of KIISE:Information Networking
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    • v.33 no.5
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    • pp.380-394
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    • 2006
  • Traditional Internet services provide the same level of qualify to all users without considering about their application's QoS (quality of service) requirements. Because the wireless and Internet technologies are evolving rapidly, the powerful mobile devices are more widely used. Therefore, the new applications such as DMB (digital multimedia broadcasting), VoD (video on demand), telemedicine, and etc. demand appropriate QoS and host mobility. To satisfy free mobility and QoS, we deploy Diffserv (differentiated services) model to the mobile IPv6 networks. We propose the operational procedures and cost analyzing models for providing an MN's mobility and QoS. Also its performance is presented by cost analyzing and the future works are described.

Perspectives on Clinical Informatics: Integrating Large-Scale Clinical, Genomic, and Health Information for Clinical Care

  • Choi, In Young;Kim, Tae-Min;Kim, Myung Shin;Mun, Seong K.;Chung, Yeun-Jun
    • Genomics & Informatics
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    • v.11 no.4
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    • pp.186-190
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    • 2013
  • The advances in electronic medical records (EMRs) and bioinformatics (BI) represent two significant trends in healthcare. The widespread adoption of EMR systems and the completion of the Human Genome Project developed the technologies for data acquisition, analysis, and visualization in two different domains. The massive amount of data from both clinical and biology domains is expected to provide personalized, preventive, and predictive healthcare services in the near future. The integrated use of EMR and BI data needs to consider four key informatics areas: data modeling, analytics, standardization, and privacy. Bioclinical data warehouses integrating heterogeneous patient-related clinical or omics data should be considered. The representative standardization effort by the Clinical Bioinformatics Ontology (CBO) aims to provide uniquely identified concepts to include molecular pathology terminologies. Since individual genome data are easily used to predict current and future health status, different safeguards to ensure confidentiality should be considered. In this paper, we focused on the informatics aspects of integrating the EMR community and BI community by identifying opportunities, challenges, and approaches to provide the best possible care service for our patients and the population.

QoS-Guaranteed Capacity of Centralized Cognitive Radio Networks with Interference Averaging Techniques

  • Wang, Jing;Lin, Mingming;Hong, Xuemin;Shi, Jianghong
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.8 no.1
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    • pp.18-34
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    • 2014
  • It is widely believed that cognitive radio (CR) networks have an opportunistic nature and therefore can only support best-effort traffics without quality-of-service (QoS) guarantees. In this paper, we propose a centralized CR network that adopts interference averaging techniques to support QoS guaranteed traffics under interference outage constraints. In such a CR network, a CR user adaptively adjusts its transmit power to compensate for the channel loss, thereby keeping the receive signal power at the CR base station (BS) at a constant level. The closed-form system capacity of such a CR network is analyzed and derived for a single cell with one CR BS and multiple CR users, taking into account various key factors such as interference outage constraints, channel fading, cell radius, and locations of primary users. The accuracy of the theoretical results is validated by Monte Carlo simulations. Numerical and simulation results show promising capacity potential for deploying QoS-guaranteed CR networks in frequency bands with fixed primary receivers. Our work can provide theoretical guidelines for the strategic planning of centralized CR networks.

QoS Aware Energy Allocation Policy for Renewable Energy Powered Cellular Networks

  • Li, Qiao;Wei, Yifei;Song, Mei;Yu, F. Richard
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.10 no.10
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    • pp.4848-4863
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    • 2016
  • The explosive wireless data service requirement accompanied with carbon dioxide emission and consumption of traditional energy has put pressure on both industria and academia. Wireless networks powered with the uneven and intermittent generated renewable energy have been widely researched and lead to a new research paradigm called green communication. In this paper, we comprehensively consider the total generated renewable energy, QoS requirement and channel quality, then propose a utility based renewable energy allocation policy. The utility here means the satisfaction degree of users with a certain amount allocated renewable energy. The energy allocation problem is formulated as a constraint optimization problem and a heuristic algorithm with low complexity is derived to solve the raised problem. Numerical results show that the renewable energy allocation policy is applicable not only to soft QoS, but also to hard QoS and best effort QoS. When the renewable energy is very scarce, only users with good channel quality can achieve allocated energy.

A customized framework for assessing R&D process: Product, service and technology (신제품, 신서비스, 신기술 개발을 위한 맞춤화된 R&D 프로세스 평가 방법론)

  • Jo, Yeongran;Lee, Sungjoo;Yoon, Jea Wook
    • Journal of Technology Innovation
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    • v.20 no.2
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    • pp.109-134
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    • 2012
  • In this era of globalization and fierce competition, R&D is an essential part of corporate development strategy. Accordingly, much effort has been devoted to identify and verify best practices for successful R&D and to improve R&D processes. Nevertheless, there is still lack of a comprehensive framework for assessing the quality of R&D process, which can be used as a step-by-step guide for process improvement. Therefore, this study purposes to develop a framework for assessing R&D process based on the concept of CMMI, which is a process improvement approach that defines the essential elements of effective processes. In particular, we suggest three types of R&D process-new product development, new service creation and new technology creation-and then develop a customized framework for them. For this purpose, we firstly investigated the characteristics of R&D activities for each type of process and identify its base practices from an extensive literature review. Then, the CMMI approach was adopted and modified to suit the R&D process. Finally, an illustrative example was provided to demonstrate the assessment process and a prototype web-based assessment system was suggested. Research findings will help understand the characteristics of different types of R&D process and provide a customized guidelines for R&D process assessment and improvement.

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Transmission of Continuous Media by Send-rate Control and Packet Drop over a Packer Network (패킷망에서 전송율 제어와 패킷 폐기에 의한 연속 미디어 전송방안)

  • 배시규
    • Proceedings of the Korea Society for Industrial Systems Conference
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    • 1999.12a
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    • pp.121-129
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    • 1999
  • When continuous media are transmitted over the communication networks, asynchrony which can not maintain temporal relationships among packets may occur due to a random transit delay. There exist two types of synchronization schemes ; for guaranteed or non-guaranteed resource networks. The former which applies a resource reservation technique maintains delay characteristics, however, the latter supply a best-effort service. In this paper, I propose a intra-media synchronization scheme to transmit continuous media on general networks not guaranteeing a bounded delay tome. The scheme controls transmission times of the packets by estimating next delay time with the delay distribution. So, the arriving packets may be maintained within a limited delay boundary, and playout will be performed after buffering to smoothen small delay variations. The continually increasing delay due to network overload causes buffer underflow at the receiver. To solve it, the transmitter is required to speed up instantaneously. Too much increase of transmission-rate may cause network congestion. At that time, the transmitter drops the current packet when informed excessive delay from the receiver.

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