• 제목/요약/키워드: Heterogeneous Communication

검색결과 648건 처리시간 0.03초

M2M/IoT 서비스를 위한 지그비 기반의 Publish/Subscr ibe 시스템 구현 (Implementation of Zigbee-based Publish/Subscribe System for M2M/IoT Services)

  • 이도경;최덕재
    • 한국멀티미디어학회논문지
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    • 제17권12호
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    • pp.1461-1472
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    • 2014
  • Recently, smart devices has been spreaded and the definition of RFID/USN(Radio Frequency Identification/Ubiquitous Sensor Network) technology has also extended. So, originally, human is an agent of communications but now, 'the things' are also an agent of communication. That is, Internet of Things(IoT). IoT is very big IT infra technology that is based on wire-wireless network technologies such as Bluetooth and Wi-Fi. However, in reality, IoT service that can provide various meaning and integrate smoothly is not appear yet. To solve these problems of IoT, we implemented Publish/Subscribe system, which operate in Zigbee based wireless sensor network by using MQTT-SN protocol. Moreover, this system can operate with combining MQTT system that is already existed in external Internet network so, extensibility and flexibility aspect is excellent. We show that possibility of IoT services that is combined between different heterogeneous network through the MQTT-SN.

"난경(難經)" 맥진조(脈診條) 중 일난~팔란(一難~八難)의 영역(英譯) 연구(硏究) (An English Translation Study on the First Eight Issues about Pulse Diagnosis of "Classic of Difficult Issues(難經)")

  • 김지영;백진웅
    • 대한한의학원전학회지
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    • 제22권3호
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    • pp.187-202
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    • 2009
  • The globalization of oriental medicine can be interpreted as the work of making its own contents able to be communicated among global heterogeneous cultural groups. In the field of oriental medical classics the work is to translate its classics into English and introduce them to researchers of oriental medicine in the world, which is essential in order to stimulate global academic communication in that the classics are the prototype as well as the source of oriental medical knowledge for thousands of years. Previous English translation studies have had limits in that terms used were not based on mutual agreement. Now "WHO International Standard Terminologies on Traditional Medicine in the Western Pacific Region(WHO-IST)" is the outcome of developing standard terminologies on oriental medicine contributed by researchers of Korea, China and Japan. The study aims to translate parts of "Classic of difficult issues(難經)" into English adopting "WHO-IST" hoping to set a model of translation study which can be communicated universally.

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이동 에이전트를 이용한 분산환경 하에서의 XML-기반 관광정보시스템 (XML-Based Tourism Information System Using Mobile Agent under Distributed Environment)

  • 이동철;최덕원
    • 한국정보통신학회논문지
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    • 제9권3호
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    • pp.654-660
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    • 2005
  • W3C에서 XML을 인터넷 환경에서 정보교환의 문서표준으로 채택함에 따라 XML 사용자가 증가하고 있다. 인터넷 환경에서는 다양한 하드웨어, 소프트웨어 플랫폼이 공존하고 있고 네트워크의 연결이 제한적이다. 한편 다양한 종류의 정보가 생산되고 또한 정보의 내용이 수시로 변화하는 관광산업의 특성에 맞추어 적절한 시간에 사용자의 의도에 맞게 정보를 가공하여 신뢰성 있는 수단으로 적시에 고객에게 관광정보를 제공할 수 있는 시스템이 필요하다. 본 연구는 이동 컴퓨팅 플랫폼과 분산되고 이질적인 환경 하에서 안정적이고 신뢰성 있게 정보를 전송할 수 있는 관광정보 시스템에 관한 논문이다.

FD/CD 트랜스코딩기법에서 CD에 의한 왜곡 분석 (An Analysis of CD Distortions in Simple FD/CD Transcoding Algorithm)

  • 김진수;김재곤;강경옥;김진웅
    • 한국정보통신학회:학술대회논문집
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    • 한국해양정보통신학회 2003년도 추계종합학술대회
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    • pp.105-108
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    • 2003
  • 이기종의 망과 다양한 종류의 사용자 단말 보급으로 디지털 영상 컨텐츠를 효과적으로 제공하는 기술이 요구되고 있고, 이를 위한 한 가지 접근 방법으로서 트랜스코딩 기법에 대한 연구가 활발히 진행되고 있다. 특히, FD(Frame Dropping)/CD(Coefficient Dropping)기법은 VLC영역에서 트랜스코딩을 수행하여 계산량을 절감하고, 가장 손쉽게 구현할 수 있는 기법으로 고려되고 있다. 그러나, 이기법에 근거한 기존의 연구 결과는 이전 프레임의 CD로 인해 현재 프레임에 전파되어 오는 왜곡 특성을 적절히 분석하지 않고 적용되고 있다. 본 논문에서는 VLC영역에서 수행되는 CD에 따른 왜곡의 특성 및 관계를 수식적으로 유도하고, 또한, 각 왜곡의 특성을 실험적으로 분석한다. 모의실험을 통하여 본 논문에서 분석된 결과들은 VLC영역에서의 효과적인 FD/CD기법을 구하는데 효과적으로 사용될 수 있을 것이다.

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모바일 환경에 적합한 상황정보 기반 서비스 프레임워크의 개발 (Implementation of Context based Service Framework for Mobile Environment)

  • 정성훈;강범석;윤형민;한탁돈
    • 한국정보처리학회:학술대회논문집
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    • 한국정보처리학회 2005년도 춘계학술발표대회
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    • pp.1381-1384
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    • 2005
  • 빠른 속도로 확산되고 있는 모바일 기기는 카메라, GPS, RFID 등과 같은 다양한 센서를 장착하고 Wi-Fi, WiMAX, WiBro 등의 무선 네트워크를 지원하는 형태로 발전하고 있다. 이러한 발전으로 사용자는 언제 어디서나 주변의 컴퓨팅 자원을 이용할 수 있게 되었고 모바일 기기의 서비스는 주변의 센서 또는 임베디드 컴퓨팅 장치로부터 수집되는 다양한 주변 환경 정보와 시스템 상태정보, 네트워크 상황정보 등의 디지털 정보를 이용하여 주변상황인식(context awareness)이 가능한 스마트 서비스로 발전하고 있다. 주변상황인식을 위하여 서비스는 주변에 존재하는 다양한 장치를 효율적으로 검색하고 이질적인(Heterogeneous) 장치와 정보의 표현 및 전송에 대한 호환성이 필요하다. 이러한 문제는 규격화된 프레임워크의 사용으로 해결할 수 있으며 상황정보의 관리 기능을 추가하여 서비스 개발의 생산성을 높일 수 있다 본 논문에서는 모바일 컴퓨팅 환경에서 상황정보의 제공과 사용에 적합한 프레임워크로서 MoCE(Mobile Context Exploerer) 아키텍처를 설계하였다. MoCE 는 상황정보의 수집, 변환, 분류, 통합 등의 기능을 제공하고 모바일 환경의 특성에 기인한 상황정보 발견 및 전송 프로토콜을 설계하여 사용하고 있다. 또한 Surround multiCam 서비스 예제를 구현하여 제안한 아키텍처의 안정성 및 성능을 실험하였다.

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QoS Priority Based Femtocell User Power Control for Interference Mitigation in 3GPP LTE-A HetNet

  • Ahmad, Ishtiaq;Kaleem, Zeeshan;Chang, KyungHi
    • 한국통신학회논문지
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    • 제39B권2호
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    • pp.61-74
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    • 2014
  • In recent years, development of femtocells are receiving considerable attention towards increasing the network coverage, capacity, and improvement in the quality of service for users. In 3GPP LTE-Advanced (LTE-A) system, to efficiently utilize the bandwidth, femtocell and macro cell uses the same frequency band, but this deployment poses a technical challenge of cross-tier interference to macro users. In this paper, the novel quality of service based fractional power control (QoS-FPC) scheme under the heterogeneous networks environment is proposed, which considers the users priority and QoS-requirements during the power allocation. The proposed QoS-FPC scheme has two focal points: firs, it protects the macrocell users uplink communication by limiting the cross-tier interference at eNB below a given threshold, and second, it ensures the optimization of femtocell users power allocation at each power adjustment phase. Performance gain is demonstrated with extensive system-level simulations to show that the proposed QoS-FPC scheme significantly decreases the cross-tier intereference and improves the overall users throughput.

Development of Distributed Interactive Stochastic Combat Simulation (DISCSIM) Model

  • Hong, Yoon-Gee;Kwon, Soon-Jong
    • 한국국방경영분석학회지
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    • 제25권2호
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    • pp.15-30
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    • 1999
  • A number of combat simulation models are scattered and the analytic solution approaches have experienced very difficult computational efforts. Today´s computer communication technology let people to do many unrealistic things possible and the use of those technologies is becoming increasingly prevalent throughout the military operation. Both DIS and ADS are welled defined computer aided military simulations. This study discusses a simulation of stochastic combat network modeling through Internet space. We have developed two separate simulation models, one for clients and another for server, and validated for conducting studies with these models. The object-oriented design was necessary to define the system entities and their relationship, to partition functionality into system entities, and to transform functional metrics into realizations derived from system component behaviors. Heterogeneous forces for each side are assumed at any battle node. The time trajectories for mean number of survivors and combat history at each node, some important combat measures, and relative difference computations between models were made. We observe and may conclude that the differences exit and some of these are significant based on a limited number of experiments.

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차량 네트워크 시스템을 위한 노드 매핑 기반 FlexRay-CAN 게이트웨이 구현 (Implementation of Node Mapping-based FlexRay-CAN Gateway for In-vehicle Networking System)

  • 배용경;김만호;이석;이경창
    • 한국자동차공학회논문집
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    • 제19권6호
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    • pp.37-45
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    • 2011
  • As vehicles become more intelligent, in-vehicle networking (IVN) systems such as controller area network (CAN) or FlexRay are essential for convenience and safety of drivers. To expand the applicability of IVN systems, attention is currently being focused on the communication between heterogeneous networks such as body networking and chassis networking systems. A gateway based on message mapping method was developed to interconnect FlexRay and CAN networks. However, this type of gateways has the following shortcomings. First, when a message ID was changed, the gateway must be reloaded with a new mapping table reflecting the change. Second, if the number of messages to be transferred between two networks increase, software complexity of gateway increases very rapidly. In order to overcome these disadvantages, this paper presents FlexRay-CAN gateway based on node mapping method. More specifically, this paper presents a node mapping based FlexRay-CAN gateway operation algorithm along with the experimental evaluation for ID change.

Mobile Web Service Architecture Using Context-store

  • Oh, Sang-Yoon;Aktas, Mehmet;Fox, Geoffrey C.
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제4권5호
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    • pp.836-858
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    • 2010
  • Web Services allow a user to integrate applications from different platforms and languages. Since mobile applications often run on heterogeneous platforms and conditions, Web Service becomes a popular solution for integrating with server applications. However, because of its verbosity, XML based SOAP messaging gives the possible overhead to the less powerful mobile devices. Based on the mobile client's behavior that it usually exchanges messages with Web Service continuously in a session, we design the Handheld Flexible Representation architecture. Our proposed architecture consists of three main components: optimizing message representation by using a data format language (Simple_DFDL), streaming communication channel to reduce latency and the Context-store to store context information of a session as well as redundant parts of the messages. In this paper, we focus on the Context-store and describe the architecture with the Context-store for improving the performance of mobile Web Service messaging. We verify our approach by conducting various evaluations and investigate the performance and scalability of the proposed architecture. The empirical results show that we save 40% of transit time between a client and a service by reducing the message size. In contrast to solutions for a single problem such as the compression or binarization, our architecture addresses the problem at a system level. Thus, by using the Context-store, we expect reliable recovery from the fault condition and enhancing interoperability as well as improving the messaging performance.

Alteration of Gut Microbiota in Autism Spectrum Disorder: An Overview

  • Oh, Donghun;Cheon, Keun-Ah
    • Journal of the Korean Academy of Child and Adolescent Psychiatry
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    • 제31권3호
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    • pp.131-145
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    • 2020
  • The microbiota-gut-brain axis, which refers to the bidirectional communication pathway between gut bacteria and the central nervous system, has a profound effect on important brain processes, from the synthesis of neurotransmitters to the modulation of complex behaviors such as sociability and anxiety. Previous studies have revealed that the gut microbiota is potentially related to not only gastrointestinal disturbances, but also social impairment and repetitive behavior-core symptoms of autism spectrum disorder (ASD). Although studies have been conducted to characterize the microbial composition in patients with ASD, the results are heterogeneous. Nevertheless, it is clear that there is a difference in the composition of the gut microbiota between ASD and typically developed individuals, and animal studies have repeatedly suggested that the gut microbiota plays an important role in ASD pathophysiology. This possibility is supported by abnormalities in metabolites produced by the gut microbiota and the association between altered immune responses and the gut microbiota observed in ASD patients. Based on these findings, various attempts have been made to use the microbiota in ASD treatment. The results reported to date suggest that microbiota-based therapies may be effective for ASD, but largescale, well-designed studies are needed to confirm this.