• Title/Summary/Keyword: Capture 효과

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A Fair MAC Algorithm under Capture Effect in IEEE 802.11 DCF -based WLANs (IEEE 802.11 무선랜에서 캡쳐 효과를 고려한 Fair MAC 알고리즘)

  • Jeong, Ji-Woong;Choi, Sun-Woong;Kim, Chong-Kwon
    • Journal of KIISE:Information Networking
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    • v.37 no.5
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    • pp.386-395
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    • 2010
  • Widespread deployment of infrastructure WLANs has made Wi-Fi an integral part of today's Internet access technology. Despite its crucial role in affecting end-to-end performance, past research has focused on MAC protocol enhancement, analysis, and simulation-based performance evaluation without sufficiently considering a misbehavior stemming from capture effect. It is well known that the capture effect occurs frequently in wireless environment and incurs throughput unfairness between nodes. In this paper, we propose a novel Fair MAC algorithm which achieves fairness even under physically unfair environment. While satisfying the fairness, the proposed algorithm maximizes the system throughput. Extensive simulation results show that the proposed Fair MAC algorithm substantially improves fairness without throughput reduction.

An RFID Tag Identification Protocol with Capture Effects (캡쳐 효과를 고려한 RFID 태그 인식 프로토콜)

  • Park, Young-Jae;Kim, Young-Beom
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.49 no.1
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    • pp.19-25
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    • 2012
  • In evaluating the performance of RFID systems, the tag anti-collision arbitration has been considered to be an important issue. For BT(Binary Tree) and ABS( Adaptive Binary Splitting) protocols, the so-called capture effect, which presumably happens frequently in the process of readers' receiving messages from multiple tags, can lead to some failures in detecting all tags in BT and ABS. In this paper, we propose a new anti-collision protocol, namely FTB (Feedback TagID with Binary splitting), which can solve the aforementioned problem and improve the performance.

HTML5_-based Mobile Web Capture Video Learning System (HTML5_기반 모바일 웹 캡쳐 동영상 학습 시스템)

  • Lee, Yean-Ran;Lim, Young-Hwan
    • The Journal of the Korea Contents Association
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    • v.13 no.2
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    • pp.8-18
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    • 2013
  • In this paper, we capture learning while taking a video, play time and time line of the video frame in the form of areas that require re-learning in HTML5 mobile web store. When you select an image frame can display a list of the frame to take advantage of HTML5 Video tag up to 9 capture and save the playing time at the position. Implemented in a manner that runs Effects as compared to learning to run the entire frame capture learning and re-learning frame partial immersion learners matchumhyeong storytelling can be implemented. Interval Iterative Learning in a random order, so learners can level alignment by iterative learning on academic performance can have a positive effect.

The Multi-marker Tracking for Facial Optical Motion Capture System (Facial Optical Motion Capture System을 위한 다중 마커의 추적)

  • 이문희;김경석
    • Proceedings of the Korea Multimedia Society Conference
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    • 2000.04a
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    • pp.474-477
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    • 2000
  • 최근 3D 애니메이션 , 영화 특수효과 그리고 게임제작시 모션 캡처 시스템(Motion Capture System)을 통하여 실제 인간의 동작 및 표정을 수치적으로 측정해내어 이를 실제 애니메이션에 직접 사용함으로써 막대한 작업시간 및 인력 드리고 자본을 획기적으로 줄이고 있다. 그러나 기존의 모션 캡처 시스템은 고속 카메라를 이용함으로써 가격이 고가이고 움직임 추적에서도 여러 가지 문제점을 가지고 있다. 본 논문에서는 일반 저가의 카메라와 신경회로망 및 영상처리를 이용하여 얼굴 애니메이션용 모션 캡처 시스템에 적용할 수 있는 경제적이고 효율적인 얼굴 움직임 추적 기법을 제안한다.

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Mobile Web Capture notes system Research on learning maturity (모바일 웹 캡처 메모 시스템의 학습 완성도에 대한 연구)

  • Lee, Yean-Ran;Lim, Young-Hwan
    • Cartoon and Animation Studies
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    • s.32
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    • pp.363-381
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    • 2013
  • In this paper, on the web, offline mobile learning content to reinforce the learning of the video frame-by-frame necessary for re-learning area to capture only the important areas. The frame of the captured image and the image in the form of advanced training time saved and also a description of the notes feature to store. The area needed for the capture area re-learning the learner to learner-centered custom systems can be applied. In order to capture the learning program, regardless of the configuration of the selected frame by frame in order to capture the user-centric storytelling-based learning can be applied. Capture the full effect of the system compared to learning and learner-centered learning time-saving reconstruction of the frame according to the customized learning to play a positive role in improving effectiveness.

Storing and Retrieving Motion Capture Data based on Motion Capture Markup Language and Fuzzy Search (MCML 기반 모션캡처 데이터 저장 및 퍼지 기반 모션 검색 기법)

  • Lee, Sung-Joo;Chung, Hyun-Sook
    • Journal of the Korean Institute of Intelligent Systems
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    • v.17 no.2
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    • pp.270-275
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    • 2007
  • Motion capture technology is widely used for manufacturing animation since it produces high quality character motion similar to the actual motion of the human body. However, motion capture has a significant weakness due to the lack of an industry wide standard for archiving and retrieving motion capture data. In this paper, we propose a framework to integrate, store and retrieve heterogeneous motion capture data files effectively. We define a standard format for integrating different motion capture file formats. Our standard format is called MCML (Motion Capture Markup Language). It is a markup language based on XML (eXtensible Markup Language). The purpose of MCML is not only to facilitate the conversion or integration of different formats, but also to allow for greater reusability of motion capture data, through the construction of a motion database storing the MCML documents. We propose a fuzzy string searching method to retrieve certain MCML documents including strings approximately matched with keywords. The method can be used to retrieve desired series of frames included in MCML documents not entire MCML documents.

Maximizing the capacity of the IoT-based WSNs by employing the MIM capability (MIM 적용을 통한 IoT 기반 무선 센서 네트워크 성능 최대화 방안)

  • Kang, Young-myoung
    • Journal of Convergence for Information Technology
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    • v.10 no.11
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    • pp.9-15
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    • 2020
  • Wireless sensor nodes adopting the advanced preamble detection function, Message-In-Mesage (MIM), maximize the concurrent transmission opportunities due to the capture effect, result in improving the system performance significantly compared to the legacy IEEE 802.15.4 based sensor devices. In this paper, we propose an MIM capture probability model to analyze the performance gains by applying the MIM function to the wireless sensor nodes. We implemented the IEEE 802.15.4 and MIM by Python and performed extensive simulations to verify the performance gains through MIM capture effects. The evaluation results show that the MIM sensors achieve 34% system throughput gains and 31% transmission delay gains over the legacy IEEE 802.15.4-based sensors, which confirm that it was consistent with the analysis result of the proposed MIM capture probability model.

Performance Analysis of CSMA/CD in Radio Environment with Capture Effect (무선환경에서 포획효과를 고려한 CSMA/CD 프로토콜의 성능분석)

  • Sa, Ju-Hee;Hyun, In-Bok;Kwak, Kyung-Sup
    • Journal of IKEEE
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    • v.1 no.1 s.1
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    • pp.73-82
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    • 1997
  • In this paper we analyzed, using Markov modeling, the performance of CSMA/CD over the wireless channel which is characterized by near-far effect, shadowing and Rayleigh fading. The analysis shows that throughput of CSMA/CD is degraded by channel error. However, if capture effect which arises from the randomness of power level of received signal due to the fading phenomena of electromagnetic waves is taken into consideration, the system performance is much improved and the system stability is also made better.

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The establishment of Digital Image Capture System(DICS) using conventional simulator (Conventional simulator를 이용한 Digital image capture system(DICS)의 구축)

  • Oh Taesung;Park Jongil;Byun Youngsik;Shin HyunKyoh
    • The Journal of Korean Society for Radiation Therapy
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    • v.16 no.2
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    • pp.25-32
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    • 2004
  • Purpose : The simulator is used to determine patient field and ensure the treatment field, which encompasses the required anatomy during patient normal movement such as during breathing. The latest simulator provide real time display of still, flouroscopic and digitalized image, but conventional simulator is not yet. The purpose of this study is to introduce digital image capture system(DICS) using conventional simulator and clinical case using digital captured still and flouroscopic image. Methods and materials : We connect the video signal cable to the video terminal in the back up of simulator monitor, and connect the video jack to the A/D converter. After connection between the converter jack and computer, We can acquire still image and record flouroscopic image with operating image capture program. The data created with this system can be used in patient treatment, and modified for verification by using image processing software. (j.e. photoshop, paintshop) Result : DICS was able to establish easy and economical procedure. DCIS image was helpful for simulation. DICS imaging was powerful tool in the evaluation of the department specific patient positioning. Conclusion : Because the commercialized simulator based of digital capture is very expensive, it is not easily to establish DICS simulator in the most hospital. DICS using conventional simulator enable to utilize the practical use of image equal to high cost digitalized simulator and to research many clinical cases in case of using other software program.

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Characteristics of Carbon Capture by the Accelerated Carbonation Method of Circulating Fluidized Bed Combustion Ash (순환 유동층 보일러 애시의 촉진탄산화에 의한 탄소포집 특성)

  • Choi, Young-Cheol;Yoo, Sung-Won
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.25 no.5
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    • pp.165-172
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    • 2021
  • The purpose of this study is to investigate the carbon capture capacity of various inorganic materials. For this purpose, the change in property of ordinary Portland cement (OPC), blast furnace slag fine powder (GGBS), and circulating fluidized bed boiler ash (CFBC) due to carbonation were analyzed. Carbonation curing was performed on all specimens through the accelerated carbonation experiment, and the amount of carbon capture was quantitatively analyzed by thermogravimetric analysis according to the age of carbonation. From the results, it is confirmed that the carbon capture capacity was shown in all specimens. The carbon capture amount was shown in the order of CFBC, OPC, and GGBS. The 28-day carbon capture of CFBC, OPC, and GGBS was 3.9%, 1.3%, and 9.4%, respectively. Carbon capture reaction occurred rapidly at the beginning of carbonation, and occurred slowly with increasing age. SEM image analysis revealed that an additional product generated by carbonation curing in all specimens was calcium carbonate.