• 제목/요약/키워드: Effective time interval

검색결과 314건 처리시간 0.029초

SIT를 이용한 무선 IPTV의 효율적인 배칭(Baching) 기법 (An Effective Batching Scheme Utilizing SIT for Wireless IPTV)

  • 유한구;김경태;최준열;윤희용
    • 한국컴퓨터정보학회:학술대회논문집
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    • 한국컴퓨터정보학회 2010년도 제42차 하계학술발표논문집 18권2호
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    • pp.253-255
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    • 2010
  • IPTV 서비스는 무선 통신 지역의 요구가 증가되고 있다. 또한 사용자들이 제한된 자원을 지원하기 위해 효율적인 전송 기술은 개발되어야 한다. 본문에서 우리는 전반적인 무선 IPTV의 VoD 시스템 성능 향상을 위해 효율적인 batching 기법을 제안한다. 이 제안은 채널 사용을 극대화하기 위해 SIT(Segment Interval Time)을 활용하였다. 현재의 Batching 기법은 많은 수의 채널을 사용하는 반면에 우리가 제안한 기법은 적은 수의 채널을 사용하여 VoD의 빠른 서비스를 보여준다. 또한 재생 지연 시간도 줄어든다.

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심자도 신호 획득을 위한 고속 병렬 데이터 전송 구현 (Implementation of high-speed parallel data transfer for MCG signal acquisition)

  • 이동하;유재택
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2004년도 추계학술대회 논문집 Vol.17
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    • pp.444-447
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    • 2004
  • A heart diagnosis system adopts hundreds of Superconducting Quantum Interface Device(SQUID) sensors for precision MCG(Magnetocardiogram) or MEG(Magnetoencephalogram) signal acquisitions. This system requires correct and real-time data acquisition from the sensors in a required sampling interval, i.e., 1 mili-second. This paper presents our hardware design and test results, to acquire data from 256 channel analog signal with 1-ksample/sec speed, using 12-bit 8-channel ADC devices, SPI interfaces, parallel interfaces, and 8-bit microprocessors. We chose to implement parallel data transfer between microprocessors as an effective way of achieving such data collection. Our result concludes that the data collection can be done in 250 ${\mu}sec$ time-interval.

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초음파를 활용한 회전근개 간격으로 접근한 견관절 주사법 (Ultrasound Guided Shoulder Joint Injection through Rotator Cuff Interval)

  • 임종범;김영기;김성우;성규완;정일;이청
    • The Korean Journal of Pain
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    • 제21권1호
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    • pp.57-61
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    • 2008
  • Background: Shoulder joint injection is currently performed under fluoroscopic or computed tomography scan guidance. We performed this study to determine if an ultrasound guided shoulder joint injection through rotator cuff interval would have clinical usefulness. Methods: A total of 17 volunteers [12 women, 5 men; mean age 28 yr (23-32 yr)] received shoulder joint injection under multilinear ultrasound (5-10 MHz). Volunteers were positioned supinely on a table with their arm in a neutral position. The anterior shoulder region of the patient was sterilized using povidone iodine. A 24 gauge needle was introduced and directly visualized in real time as it passed obliquely from the skin surface to the inferior space of the biceps tendon. If there was little or no resistance to the injection, a contrast media (omnipaque) was injected and checked fluoroscopically. Results: Ultrasound guided shoulder joint injection through rotator cuff interval was successful in all cases. The average time taken for the procedure was $27.5{\pm}16.5sec$. The vertical distance from skin to the inferior space of the biceps tendon was $1.6{\pm}0.4cm$ and the distance of needle from the skin to the inferior space of biceps tendon was $2.8{\pm}0.6cm$. The procedure was well tolerated by all volunteers. Conclusions: Ultrasound guided shoulder joint injection through rotator cuff interval is an effective, rapid, and easy-to-perform injection technique. Ultrasound guided injection enables exact needle placement and avoids the use of both ionizing radiation and iodinated contrast material.

동영상 트래픽 전송을 위한 효과적인 QoS 재협상 기법 (Effective Quality-of-Service Renegotiating Schemes for Streaming Video)

  • 이대붕;송황준
    • 한국통신학회논문지
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    • 제28권6C호
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    • pp.615-623
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    • 2003
  • 동영상 트래픽은 자체의 non-stationary한 특성들로 인해 일률적인 대역폭만으로는 전송 과정의 어려움이 있다. 일반적인 토큰 버킷 구조나 ATM은 한번의 자원 협상만으로 데이터를 전송하는 방법이기 때문에 이러한 문제를 극복하기 어려운 방법이다. 따라서 동영상 트래픽의 특성을 고려한 전송기법이 필요하고, 본 연구에서는 토큰 버킷 구조의 자원을 동적으로 재협상하는 방법을 제안한다. 본 연구에서 제시하는 재협상을 이용한 토큰 버킷구조는 데이터를 몇 개의 구간으로 나누어서 각 구간별 요구되는 토큰 유입량과 토큰 버킷 크기를 재협상하고 이를 자원으로 하여 동영상 데이터를 전송하는 구조이다. 이러한 재협상은 각 구간별 특성에 따라 효율적인 동영상 데이터 전송이 가능하도록 해준다.

JIT 구매 하에서 다품목의 조달정책에 관한 연구 (An Integrated Inventory Model for Multi-Item in Just-In-Time Purchasing)

  • 김대홍;김용철
    • 산업경영시스템학회지
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    • 제25권1호
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    • pp.42-48
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    • 2002
  • This paper addresses the necessity of integration between buyer and suppliers for effective implementation of Just-In-Time purchasing in a multi-item environment. An integrated inventory model of facilitating multiple shipments in small lots is developed. Also, an iterative solution procedure is developed to simultaneously find the order(contract) interval for each item and number of shipments between buyer and suppliers. We show by example that when the integrated policy is adopted by both buyer and suppliers in a cooperative manner, both parties can benefit.

In-service Real-time and Continuous Objective Video Quality Assessment for DTV Broadcasting

  • Han, Chan-Ho
    • 한국멀티미디어학회논문지
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    • 제16권1호
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    • pp.50-55
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    • 2013
  • This article presents a simple and reasonable in-service, real-time, and continuous single-ended objective video quality assessment model for DTV broadcasting using a multiburst signal at the bottom of the transient effect area, similar to Vertical Interval Test Signals. The issue of in-service video-quality monitoring in DTV broadcasting is addressed, and an effective method of quality monitoring is presented. The proposed method is also implemented and tested in a range of situations using a simulated HDTV broadcasting network.

배출권거래제 하에서 2단계 공급사슬에서 다품목의 통합재고모형 (An Integrated Multi-Product Inventory Model for a Two-Echelon Supply Chain under Cap-and-Trade Mechanism)

  • 김대홍
    • 산업경영시스템학회지
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    • 제42권4호
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    • pp.61-68
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    • 2019
  • Currently many companies are interested in reduction of the carbon emissions associated with their supply chain activities such as transportation and operations. Operational decisions, such as modifications in order quantities could an effective way in reducing carbon emissions in the supply chain. Cap-and-trade regulation, sometimes called emissions trading, is a market-based tool to limit greenhouse gas emissions. Under cap-and-trade regulation, emission credits are allocated to the firms and the firms trades emissions under cap-and-trade schemes. In this paper, we propose a single-manufacturer single-buyer two-echelon supply chain problem under the cap-and-trade mechanism incorporating the carbon emissions caused by transportation and warehousing activities where a single manufacturer produces a family of items in order to deliver a family of items to a single buyer at a fixed interval of time for effective implementation of Just-In-Time (JIT) Purchasing. An integrated multi-product lot-splitting model of facilitating multiple shipments in small lots between buyer and manufacturer is developed in a JIT Purchasing environment. Also, an iterative heuristic algorithm is developed to derive the common order interval, the number of intervals for each product and the number of shipments between the buyer and the manufacturer during the common interval. A numerical example is given to illustrate the savings in reduction of total cost and carbon emissions by the inventory model incorporating cap-and-trade mechanism compared to the classical inventory model. The proposed inventory model could be useful for the practical solution of two-echelon supply chain inventory problem under cap-and-trade mechanism.

선량 환산 관례를 이용한 생애유효선량 및 라돈피폭 위험도 예측: 대학 강의실 라돈농도 중심으로 (Prediction for the Lifetime Effective Dose and Radon Exposure Risk by using Dose Conversion Convention: Base on the Indoor Radon Concentration of Lecture Room in a University)

  • 이재승;권대철
    • 대한의용생체공학회:의공학회지
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    • 제39권6호
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    • pp.243-249
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    • 2018
  • The indoor radon concentration was measured in the lecture room of the university and the radon concentration was converted to the amount related to the radon exposure using the dose conversion convention and compared with the reference levels for the radon concentration control. The effect of indoor radon inhalation was evaluated by estimating the life effective dose and the risk of exposure. To measure the radon concentration, measurements were made with a radon meter and a dedicated analysis Capture Ver. 5.5 program in a university lecture room from January to February 2018. The radon concentration measurement was carried out for 5 consecutive hours for 24 hours after keeping the airtight condition for 12 hours before the measurement. Radon exposure risk was calculated using the radon dose and dose conversion factor. Indoor radon concentration, radon exposure risk, and annual effective dose were found within the 95% confidence interval as the minimum and maximum boundary ranges. The radon concentration in the lecture room was $43.1-79.1Bq/m^3$, and the maximum boundary range within the 95% confidence interval was $77.7Bq/m^3$. The annual effective dose was estimated to be 0.20-0.36 mSv/y (mean 0.28 mSv/y). The life-time effective dose was estimated to be 0.66-1.18 mSv (mean $0.93{\pm}0.08mSv$). Life effective doses were estimated to be 0.88-0.99 mSv and radon exposure risk was estimated to be 12.4 out of 10.9 per 100,000. Radon concentration was measured, dose effective dose was evaluated using dose conversion convention, and degree of health hazard by indoor radon exposure was evaluated by predicting radon exposure risk using nominal hazard coefficient. It was concluded that indoor living environment could be applied to other specific exposure situations.

구조자 특성별 심폐소생술 지속시간에 따른 질 변화 (Changes in quality of cardiopulmonary resuscitation over time on CPR and related rescuer)

  • 유순규;최혜경
    • 한국응급구조학회지
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    • 제16권3호
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    • pp.103-115
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    • 2012
  • Purpose : Inadequate chest compression during cardiopulmonary resuscitation(CPR) may result in the insufficient blood flow to preserve critical organ function. The study evaluated changes of quality of cardiopulmonary resuscitation over time in 30:2 CPR by laypersons and analyzed rescuer factors affecting the quality of chest compressions over time. Methods : This study was designed to know quality of CPR changes during 5 minutes. 47 students completed CPR training courses. They were performed 30:2 CPR using a manikin with Skill-Reporter for 5 minutes continuously to get data of depth, rate of chest compression, volume and correct rate of ventilation. Results : Time dependent analysis showed significant ineffective compression depth in females and under weight rescuers. In case of female, we found effective compression depth has maintained up to 2 minutes, but it decreased significantly after 2 minutes. However, underweight rescuers maintained effective compression depth up to a minute but it decreased after 1 minute. Conclusion : Although compression rate maintained over time, chest compression quality declined significantly. It suggested switching compression at an interval of 2 minutes is reasonable for 30:2 CPR by layperson but underweight rescuers may provide effective chest compression by switching shift every one minute.

모바일 그리드에서 데이터마이닝을 이용한 효율적인 사용자 패턴 연구 (Study of the effective use pattern using Data Mining in a mobile grid)

  • 김휴찬;김미정
    • 디지털산업정보학회논문지
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    • 제9권2호
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    • pp.23-32
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    • 2013
  • The purpose of this study is to make effective mobile grid considered general environment, which can be summarized as irregular mobility, service exploration, data sharing, variety of machines, limit to the battery duration, etc. The data was extracted from the Dartmouth College. We analysed mobile use pattern of a specific group and applied pattern using hybrid method. As a result, we could adjust infra usage effectively and appropriately and cost cutting and increase satisfaction of user. In this study, by applying weighting method based on access time interval, we analysed use pattern added time variation with association rule during users in mobile grid environment. We proposed more stable way to manage patterns in a mobile grid environment that is being used as a hybrid form to process the data value received from the server in real time. Further studies are needed to get appropriate use pattern by group using use patterns of various groups.