• Title/Summary/Keyword: Distribution & Service

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A Publish Subscribe Information Exchange Model and A Novel Matching Algorithm for Navy Shipboard Systems (해군 함정 컴퓨팅 체계 정보교환을 위한 Publish Subscribe 모델 기반 아키텍처 및 매칭 알고리즘)

  • Kim, Hong-Jae;Oh, Sang-Yoon
    • The KIPS Transactions:PartA
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    • v.18A no.5
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    • pp.181-192
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    • 2011
  • Information superiority is an essential factor in modern warfare and it can be archived by efficient information exchange between systems. Various computing systems are installed on the today's navy vessels. However, it is hard to improve interoperability and efficiency of information exchange since the configurations of installed systems are varying. The military standard and commercial standard are mix-used between systems. In this paper, we propose an information exchange architecture based on Pub/Sub model as a communication middleware to improve interoperability as well as enhancing scalability. We also propose a novel tree matching algorithm to improve a performance of PubSub broker. In the proposed algorithm, each tree nodes have information about predicates of subscription that can reduce event matching time. The performance evaluation results show our proposed algorithm reduces time for matching predicates compare with other algorithms.

Analysis of Average Waiting Time and Average Turnaround Time in Web Environment (웹 환경에서의 평균 대기 시간 및 평균 반환 시간의 분석)

  • Lee, Yong-Jin
    • The KIPS Transactions:PartC
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    • v.9C no.6
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    • pp.865-874
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    • 2002
  • HTTP (HyperText Transfer Protocol) is a transfer protocol used by the World Wide Web distributed hypermedia system to retrieve the objects. Because HTTP is a connection oriented protocol, it uses TCP (Transmission control Protocol) as a transport layer. But it is known that HTTP interacts with TCP badly. it is discussed about factors affecting the performance or HTTP over TCP, the transaction time obtained by the per-transaction TCP connections for HTTP access and the TCP slow-start overheads, and the transaction time for T-TCP (Transaction TCP) which is one or methods improving the performance or HTTP over TCP. Average waiting time and average turnaround time are important parameters to satisfy QoS (Quality of Service) of end users. Formulas for calculating two parameters are derived. Such formulas can be used for the environment in which each TCP or T-TCP transaction time is same or different. Some experiments and computational experiences indicate that the proposed formulas are well acted, can be applied to the environment which the extension of bandwidth is necessary, and time characteristics of T-TCP are superior to that of TCP. Also, the load distribution method of web server based on the combination of bandwidths is discussed to reduce average waiting time and average turnaround time.

User Costs Evaluation due to the Bridge Reconstruction Period (교량의 재가설 공사기간에 따른 사용자비용 평가)

  • Kim, Sang Hyo;Park, Se Jun;Lee, Dong Ho;Ahn, Jin Hee
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.15 no.1
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    • pp.148-158
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    • 2011
  • As critical infrastructure, bridges play an indispensable role in facilitating the distribution of goods. When bridges reach their end of useful life or get damaged by natural disasters such as earthquakes or storms, they have to be removed and reconstructed. When bridges in service need to be reconstructed, user costs occur from vehicle detours and traffic congestions, and social costs occur from noise and dust during construction periods. However, these user and social costs are not considered during reconstruction and the evaluation methods of those costs are vague. Thus, there is lack of appropriate bridge types that consider these costs. Therefore, this paper identifies the social overhead costs that occur during bridge reconstruction, which is also called, users' socioeconomic values. Next, it proposes a method to evaluate user costs during bridge reconstruction, and appraises the method. User costs are evaluated based on traffic information, social and material volumes including the bridge's daily traffic volume, peak hours, detour distance and time. In addition, time delay costs due to traffic operational costs and bridge reconstruction are also taken into consideration.

Traffic-based Caching Algorithm and Performance Evaluation for QoS-adaptive Streaming Proxy Server in Wireless Networks (무선 환경에서 QoS 적응적인 스트리밍 프락시 서버를 위한 트래픽 기반 캐싱 알고리즘 및 성능 분석)

  • Kim, HwaSung;Kim, YongSul;Hong, JungPyo
    • Journal of Broadcast Engineering
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    • v.10 no.3
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    • pp.313-320
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    • 2005
  • The increasing popularity of multimedia streaming services introduces new challenges in content distribution. Especially, it is important to provide the QoS guarantees as they are increasingly expected to support the multimedia applications. Multimedia streams typically experience the high start-up delay due to the large protocol overhead, the delay, and the loss properties of the wireless networks. The service providers can improve the performance of multimedia streaming by caching the initial segment (prefix) of the popular streams at proxies near the requesting clients. The proxy can initiate transmission to the client while requesting the remainder of the stream from the server. In this paper, we propose the traffic based caching algorithm (TSLRU) to improve the performance of caching proxy. TSLRU classifies the traffic into three types, and improve the performance of caching proxy by reflecting the several elements such as traffic types, recency, frequency, object size when performing the replacement decision. In simulation, TSLRU performs better than the existing schemes in terms of byte hit rate, hit rate, startup latency, and throughput.

High definition VOD contents management system design of H.264 basis (H.264기반의 고화질 VOD 콘텐츠관리시스템(CMS) 설계)

  • Min, Byoung-won;Oh, Yong-sun;Lee, Jung-man
    • Proceedings of the Korea Contents Association Conference
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    • 2008.05a
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    • pp.465-468
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    • 2008
  • Recently, VOD market is getting increased and most of public, educational organization, enterprises are providing service as content managing system of WMV standard subordinated to Window OS of Microsoft company. VOD CMS of WMV standard have problem that frequent cut-off, small-size of screen, and image quality which is also chronic problem. In order to solve this problem, technology solving the problem has developed through minimization of buffering time, screen size, high quality sound, and high quality image by image codec and streaming engine which is H. 264. But there are still a problem that systematic management of contents or distribution is difficult. This study expected that there would be a effect preoccupying significant stand of world wide H.264 high quality image mobile VOD managing market by securing domestic on-line VOD contents integrated managing technology by designing system for image VOD contents management having a limit in wmv market and combining H.264 which is new technology.

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Impact of fish consumption by subjects with prediabetes on the metabolic risk factors: using data in the 2015 (6th) Korea National Health and Nutrition Examination Surveys

  • Kim, Kyoung-yun;Park, Jeong Seop
    • Nutrition Research and Practice
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    • v.12 no.3
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    • pp.233-242
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    • 2018
  • BACKGROUND/OBJECTIVES: The effects of fish consumption by subjects with prediabetes on the metabolic risk factors were examined based on the data from the $6^{th}$ Korea National Health and Nutrition Examination Surveys in 2015. SUBJECTS/METHODS: A total of 1,520 subjects who agreed to participate in a blood test and dietary intake survey were divided into a prediabetes group and normal blood glucose group, and the level of the subjects' fish consumption was divided into ${\leq}17.0g/day$, 18.0-93.0 g/day, and ${\geq}94g/day$. The correlation between the level of fish intake and the metabolic risk factors was evaluated by multinomial logistic regression analysis. RESULTS: A significant difference in the gender distribution was observed in the prediabetes group, which is a group with a high risk of non-communicable diseases, according to the fish intake, and there were significant differences in the total energy intake, protein intake, n-3 fatty acids intake, and the intakes of sodium and micro-nutrients according to the intake group (P < 0.05). In addition, the blood total cholesterol (TC) decreased 0.422 fold in model 1 (unadjusted) [95% confidence interval (CI): 0.211-0.845] and 0.422 fold in model 2 (adjusted for sex) (95% CI: 0.210-0.846) in those with a fish intake of 18.0-93.0 g/day (P < 0.05) compared to those with a fish intake of ${\leq}17.0g/day$. The blood TC decreased 0.555 fold (95% CI: 0.311-0.989) in model 1 and 0.549 fold (95% CI: 0.302-0.997) in model 2 in those with a fish intake of ${\geq}94g/day$ compared to those with a fish intake of ${\leq}17.0g/day$ (P < 0.05). CONCLUSION: Subjects with prediabetes or the metabolic risk factors can maintain their blood low density lipoprotein cholesterol (LDL-C) and blood TC concentrations at the optimal level by consuming fish (18.0-93.0 g/day).

A Study on Concealed Damage through Car-Ferry International Multimodal Transport between Korea and Japan (한일간 카-훼리 국제복합운송에 따른 부명손해(不明損害)에 관한 연구)

  • Park, Sang-Kab;Kim, Jung-Ho
    • Journal of Navigation and Port Research
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    • v.35 no.6
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    • pp.523-531
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    • 2011
  • The recent increase in international car-ferry lines between Korea and Japan as well as China brings needs for proper transportations of special cargo, such as machinery and luxury yacht, etc. International multimodal transport, especially international car ferry through truck-sea-truck system enables to fulfill shippers' needs for "Door to Door Service", of such special goods. However, this international multimodal transport of bulk cargo will cause a possible claim for concealed damages during such transportation. For this reason, this study aims to examine the liability system of the multimodal transport operator as well as to investigate liability for concealed damages theoretically and finally to seek proper measures for them. Futhermore, this paper intends to verify the claims for concealed damages to further the international multimodal transport by car ferries between Korea and Japan.

Improved VRP & GA-TSP Model for Multi-Logistics Center (복수물류센터에 대한 VRP 및 GA-TSP의 개선모델개발)

  • Lee, Sang-Cheol;Yu, Jeong-Cheol
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.8 no.5
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    • pp.1279-1288
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    • 2007
  • A vehicle routing problem with time constraint is one of the must important problem in distribution and logistics. In practice, the service for a customer must start and finish within a given delivery time. This study is concerned about the development of a model to optimize vehicle routing problem under the multi-logistics center problem. And we used a two-step approach with an improved genetic algorithm. In step one, a sector clustering model is developed by transfer the multi-logistics center problem to a single logistics center problem which is more easy to be solved. In step two, we developed a GA-TSP model with an improved genetic algorithm which can search a optimize vehicle routing with given time constraints. As a result, we developed a Network VRP computer programs according to the proposed solution VRP used ActiveX and distributed object technology.

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Commercial Databases : The Keypoints and Practical Use(1) - Trends of Database Services - (상용(商用) 데이터베이스 : 그 요점(要點)과 활용(活用)(1) - 데이터베이스 서비스의 동향(動向) -)

  • Cho, Jae-Ho
    • Journal of Information Management
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    • v.24 no.2
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    • pp.36-53
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    • 1993
  • Nowadays we usually act based on information in order to act effectively, we should enlarge our access to information of course, we have several methods to choose from, but commercial databases are the most advantageous. One reason is that everyone has equal access to commercial databases. As a result, people or companies who use commercial database information skillfully have a distince advantage over those who don't commercial database services in japan have been changing rapidly since their birth more than twenty years ago. For example, the distribution mode of databases is changing : from the original batch(off line) to on-line and most recently to the coexistence of batch and on line with the advent of CD-ROM. It is important for us to keep up with the new trends in databases, and to utilize them effectively as a tool in the information age.

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Study of Platform for Real-Time Medical Information Protection and Management (실시간 의료정보 보호 및 관리를 위한 플랫폼에 관한 연구)

  • Jeong, Chang Won;Lee, Sung Gwon;Joo, Su Chong
    • KIPS Transactions on Computer and Communication Systems
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    • v.3 no.8
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    • pp.245-250
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    • 2014
  • In recent years, the developments of medical technology and emergency medical services have been changed to home from the hospital. In this regard, the researches for the prevention or early diagnosis have become actively. In particular, bio-signal monitoring is applied to a variety of u-healthcare application services. The proposed system in this paper is to provide a security technology to protect the medical information measured from the various sensors. Especially, bio-signal information is privacy-sensitive personal information that must be protected. We applied a two-dimensional code technology, QR code, for the protection and management. In the client side, it can analyze the QR code and confirm the results on devices. Finally, with this proposed platform, we show the results of application service to verify the creation and distribution of integrated image file between the bio-signal and medical image information.