• Title/Summary/Keyword: Video-conference

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Dynamic Channel Allocation Using SJF Scheduling in IEEE 802.11p/1609 Vehicular Network (IEEE 802.11p/1609 차량 네트워크에서 SJF(Shortest Job First) 스케쥴링을 이용한 동적 채널 할당 기법)

  • Jang, Hyun-Jun;Kwon, Yong-Ho;Rhee, Byung-Ho
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2014.10a
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    • pp.624-627
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    • 2014
  • In vehicular network, the basic goal is to provide vehicle safety service and commercial service such as ITS(Intelligent Transportation System) or video, etc on the road. And most research concentrated on transportation of safety message in congestion situation. It is important to allocate channel for safety message in congestion situation, but providing suitable service is also important problem in vehicular network. For this reason, IEEE 1609.4 allocate 4 multiple service channels (SCHs) for non-safety data transfer. But, in congestion situation with many vehicles, the contention for channel acquisition between services becomes more severe. So services are provided improperly because of lack of service channel. This paper suggests dynamic channel allocation algorithm. The proposed algorithm is that RSU(RaodSide Unit) maintain and manage the information about service and status of channels. On based of the SJF(Shortest Job First) scheduling using those information, RSU selects the most appropriate channel among the 4 SCHs allocated by IEEE 1609.4 in network congestion situation.

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Embracing Device Characteristics for Dynamic Adaptive Video Streaming (DLNA 기기 특성을 고려한 동적 적응형 스트리밍에 대한 연구)

  • Kim, Mijung;Jin, Feng;Yoon, Ilchul;Jin, Xianshu
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2014.05a
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    • pp.574-577
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    • 2014
  • Multimedia contents sharing services based on DLNA (Digital Living Network Alliance) technology such as Allshare or Smartshare in wireless home networks is widely adapted in Korea. However, the characteristics of the wireless network - frequently fluctuated bandwidth and signal strength could degrade the quality perceived by users. To minimize the impact of the challenge there are active researches in dynamic adaptive streaming. This paper proposes a dynamic adaptive streaming approach designed in a wireless network taking into account of the specifications of the user device such as resolution and processor. We modify the Kalman filter considering the characteristics of the device and demonstrate that the proposed approach determines Bit Rate using the modified filter.

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Mobile Healthcare and Security (모바일 헬스케어와 정보보안)

  • Woo, SungHee
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2016.10a
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    • pp.755-758
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    • 2016
  • The use of smart phones has had a great impact on the mobile internet business. It shows a lot of growth in the healthcare sector not only commerce, advertising, billing, games, video content, media, amd O2O business. The United States has eased the regulations for healthcare apps smart phone devices in 2015, and China has established a five-year road map to solve shortage of doctors and hospital beds by utilizing mobile devices such as wearable in the same year. The application of wearable devices in the medical field is gradually increasing in Korea too, but there is a security problem as leading challenge. Security incidents in non-ICT sectors such as financial, medical, etc. have increased by using ICT each year. Personal information leakage is also increasing in field likely occurring the potential secondary damages such as financial fraud, illegal promotions, insurance and pharmaceutical companies abuse. In this study, we analyze malwares as the mobile threats, the five risks of mobile smart phone, mobile use cases and the mobile threat countermeasures for healthcare.

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A Study of Integrated Digital Signage Management System Implementation (Digital Signage 통합관리시스템 구축에 관한 연구)

  • Kang, Hee-Yong;Lee, Jina;Shin, Yong-Tae;Kim, Jong-Bae
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2014.10a
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    • pp.82-85
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    • 2014
  • With high speed communication network and supplement of high quality multimedia devices, large demand of multimedia service stimulates digital signing industry to step forward to new opportunities. But in order to provide competitive quality services, Integrated management system is required. Digital signs use technologies such as LCD, LED and Projection to display content such as digital images, video, streaming media, and information. Digital signs rely on a variety of hardware to deliver the contents. The components of a typical digital sign installation include one or more display screens, one or more media players, and a content management server for each player. To improve the existing high cost and less efficient management system, this paper suggest cost effective Integrated Digital Signage Management System with the results of analysis of existing system. Also this paper presents an actual implementation on entertainment company to evaluate the suitability, to prove the result of superior performance of proposed system.

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A Study on game engine properties for Art college education (예술 대학 교육을 위한 게임엔진 특성 연구 (Unity와 Unreal engine을 중심으로))

  • Cho, Hyung-ik
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2019.05a
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    • pp.227-229
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    • 2019
  • Currently, people use game engines which is consist of essential elements(Graphic engine, Physics engine, Audio engine, UI system, Gameplay frameworks, etc) to develop video. This game engine is used for its own development, but usually it is used by renting a commercial engine. To be able to use such a game engine requires a lot of theoretical and functional education, but in a limited period of university education, it is impossible to deal with various game engines in game art colleges, not general engineering universities. This paper will compare and analyze the characteristics, and merits and demerits of these two kinds of Game engines (Unity and Unreal engine), and showed the result of analyses about the fact that educating which of the above 2 Game engines are helpful and beneficial for the students for the efficient education in the Art college where should teach much in the limited time.

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Efficient Intra Predictor Design for H.264/AVC Decoder (H.264/AVC 복호기를 위한 효율적인 인트라 예측기 설계)

  • Kim, Ok;Ryoo, Kwangki
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2009.10a
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    • pp.175-178
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    • 2009
  • H.264/AVC is a video coding standard of ITU-T and ISO/IEC, and widely spreads its application due to its high compression ratio more than twice that of MPEG-2 and high image quality. In this paper, we explained Intra Prediction in H.264/AVC, which is able to achieve higher compressing efficiency from correlation removal of adjacent samples in spatial domain, and proposed efficient Intra Predictor architecture design for H.264/AVC decoder. The proposed system reduced computation cycle using processing element and precomputation processing element and also reduced the number of access to external memory using efficient register. We designed the proposed system with Verilog-HDL and verified with suitable test vector. The proposed Intra Predictor achieved about 60% cycle reduction comparing with existing Intra Predictors.

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Exploring the Moderating Effect of Difficulty in Recognized Curriculum Task on the Mediator Model of Interesting and Learning Motivation on Flow in Distant PBL Classes of Pre-service Teachers (예비교사들의 원격 PBL 수업에서 몰입에 대한 흥미수준과 학습동기의 매개모형에 미치는 인식된 교육과정 과제난이도의 조절효과 탐색)

  • Lee, Eun-Chul
    • The Journal of the Korea Contents Association
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    • v.21 no.2
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    • pp.594-603
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    • 2021
  • This study explored the moderating effects of task difficulty for flow, learning motivation, and interesting in distant PBL classes of pre-service teachers. For this, the research model was constructed by analyzing previous studies. The research model verification was conducted by 105 students of taking courses in the curriculum. The distant PBL used a real-time video conference system. Cooperative activities were carried out in real time. After the end of the distant PBL activity, the level of learning motivation, interesting, flow, and task difficulty perception were measured. The collected data were analyzed using a test of the structural model invariance across the groups using a structural equation model. This analysis verifies the difference in path coefficients between measurement models. The control effect of task difficulty was verified through the difference in path coefficient. As a result, it was verified that interesting mediates the influence of learning motivation on flow. And the moderating effect of the perceived task difficulty appeared on the path from learning motivation to interesting.

A History-based Scheduler for Dynamic Load Balancing on Distributed VOD Server Environments (분산 VOD 서버 환경에서 히스토리 기반의 동적 부하분산 스케줄러)

  • Moon, Jongbae
    • Proceedings of the Korea Information Processing Society Conference
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    • 2010.04a
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    • pp.210-213
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    • 2010
  • 최근 사용자의 멀티미디어에 대한 요구의 증가가 VOD (Video-on-Demand) 서비스를 발전시키게 되었다. VOD는 엔터테인먼트나 원격 교육, 광고 및 정보 등 많은 분야에서 사용되고 있다. 이러한 VOD 서비스는 많은 디스크 I/O와 네트워크 I/O를 요구하며 기존 웹 서버 시스템과 비교했을 때 오랜 시간동안 서비스를 해야 하는 특징을 가지고 있다. 또한 VOD 서비스는 많은 네트워크와 디스크의 대역폭을 요구하며, 서비스의 QoS에 민감해서 사용자 응답시간이 길어지면 사용자 요청의 취소율이 높아지게 된다. 따라서 불만족스러운 서비스의 증가로 네트워크 부하만 증가하게 된다. 이러한 기존 웹 서버 환경과는 다른 부하의 패턴이 있는 VOD 서비스 환경에서는 부하를 균형적으로 분배하여 서비스의 QoS를 높이는 것이 매우 중요하다. 본 논문에서는 분산 VOD 시스템 환경에서 부하를 효율적으로 분산하기 위해 계층형 분산 VOD 시스템 모델과 사용자 요청 패턴의 히스토리와 유전 알고리즘을 기반으로 한 스케줄러를 제안한다. 본 논문에서 제안한 계층형 분산 VOD 시스템 모델은 서버들을 지역적으로 분산하고 제어 서버를 지역마다 설치하여 지역에 있는 VOD 서버들을 관리하도록 구성한다. 사용자 요청을 지역 서버군 내에서 분산시키기 위해서 히스토리를 기반으로 한 유전 알고리즘을 사용한다. 이러한 히스토리 정보를 기반으로 유전 알고리즘의 적합도 함수에 적용하여 VOD 시스템을 위한 유전 알고리즘과 유전 연산을 구현한다. 본 논문에서 제안한 부하 분산 알고리즘은 VOD 서비스 환경에서 사용자 요구에 대한 부하를 보다 정확하게 예측하여 부하를 분산할 수 있다. 본 논문에서 제안한 계층형 분산 VOD 시스템의 부하 분산 알고리즘의 성능을 테스트하기 위해 OPNET 기반 시뮬레이터를 구현한다. 라운드로빈(round-robin) 방식과 랜덤(random) 방식과의 비교 실험을 통해 본 논문에서 제안한 부하 분산 알고리즘의 성능을 평가한다. 비교 실험을 통해 본 논문에서 제안한 알고리즘이 보다 안정적인 QoS를 제공하는 것을 보여준다.

Enhancing the digitization of cultural heritage: State-of-Practice

  • Nguyen, Thu Anh;Trinh, Anh Hoang;Pham, Truong-An
    • International conference on construction engineering and project management
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    • 2022.06a
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    • pp.1075-1084
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    • 2022
  • The use of Hi-Tech in cultural heritage preservation and the promotion of cultural heritage values in general, particularly artifacts, opens new opportunities for attracting tourists while also posing a challenge due to the need to reward high-quality excursions to visitors historical and cultural values. Building Information Modeling (BIM) and Hi-Tech in new building management have been widely adopted in the construction industry; however, Historic Building Information Modeling (HBIM) is an exciting challenge in 3D modeling and building management. For those reasons, the Scan-to-HBIM approach involves generating an HBIM model for existing buildings from the point cloud data collected by Terrestrial 3D Laser Scanner integrated with Virtual Reality (VR), Augmented Reality (AR), contributes to spatial historic sites simulation for virtual experiences. Therefore, this study aims to (1) generate the application of Virtual Reality, Augmented Reality to Historic Building Information Modeling - based workflows in a case study which is a monument in the city; (2) evaluate the application of these technologies to improve awareness of visitors related to the promotion of historical values by surveying the experience before and after using this application. The findings shed light on the barriers that prevent users from utilizing technologies and problem-solving solutions. According to the survey results, after experiencing virtual tours through applications and video explanations, participant's perception of the case study improved. When combined with emerging Hi-Tech and immersive interactive games, the Historic Building Information Modeling helps increase information transmission to improve visitor awareness and promote heritage values.

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Prediction of Plant Operator Error Mode (원자력발전소 운전원의 오류모드 예측)

  • Lee, H.C.;E. Hollnagel;M. Kaarstad
    • Proceedings of the ESK Conference
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    • 1997.04a
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    • pp.56-60
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    • 1997
  • The study of human erroneous actions has traditionally taken place along two different lines of approach. One has been concerned with finding and explaining the causes of erroneous actions, such as studies in the psychology of "error". The other has been concerned with the qualitative and quantitative prediction of possible erroneous actions, exemplified by the field of human reliability analysis (HRA). Another distinction is also that the former approach has been dominated by an academic point of view, hence emphasising theories, models, and experiments, while the latter has been of a more pragmatic nature, hence putting greater emphasis on data and methods. We have been developing a method to make predictions about error modes. The input to the method is a detailed task description of a set of scenarios for an experiment. This description is then analysed to characterise thd nature of the individual task steps, as well as the conditions under which they must be carried out. The task steps are expressed in terms of a predefined set of cognitive activity types. Following that each task step is examined in terms of a systematic classification of possible error modes and the likely error modes are identified. This effectively constitutes a qualitative analysis of the possibilities for erroneous action in a given task. In order to evaluate the accuracy of the predictions, the data from a large scale experiment were analysed. The experiment used the full-scale nuclear power plant simulator in the Halden Man-Machine Systems Laboratory (HAMMLAB) and used six crews of systematic performance observations by experts using a pre-defined task description, as well as audio and video recordings. The purpose of the analysis was to determine how well the predictions matiched the actually observed performance failures. The results indicated a very acceptable rate of accuracy. The emphasis in this experiment has been to develop a practical method for qualitative performance prediction, i.e., a method that did not require too many resources or specialised human factors knowledge. If such methods are to become practical tools, it is important that they are valid, reliable, and robust.

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