• 제목/요약/키워드: Time Awareness

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Development of a Data Reduction algorithm for Optical Wide Field Patrol

  • Park, Sun-Youp;Keum, Kang-Hoon;Lee, Seong-Whan;Jin, Ho;Park, Yung-Sik;Yim, Hong-Suh;Jo, Jung Hyun;Moon, Hong-Kyu;Bae, Young-Ho;Choi, Jin;Choi, Young-Jun;Park, Jang-Hyun;Lee, Jung-Ho
    • Journal of Astronomy and Space Sciences
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    • 제30권3호
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    • pp.193-206
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    • 2013
  • The detector subsystem of the Optical Wide-field Patrol (OWL) network efficiently acquires the position and time information of moving objects such as artificial satellites through its chopper system, which consists of 4 blades in front of the CCD camera. Using this system, it is possible to get more position data with the same exposure time by changing the streaks of the moving objects into many pieces with the fast rotating blades during sidereal tracking. At the same time, the time data from the rotating chopper can be acquired by the time tagger connected to the photo diode. To analyze the orbits of the targets detected in the image data of such a system, a sequential procedure of determining the positions of separated streak lines was developed that involved calculating the World Coordinate System (WCS) solution to transform the positions into equatorial coordinate systems, and finally combining the time log records from the time tagger with the transformed position data. We introduce this procedure and the preliminary results of the application of this procedure to the test observation images.

무선 센서네트워크에서 상황인식기반 실시간 감시시스템 개발 (Development of Real Time Monitoring System based on Context-awareness for Wireless Sensor Networks)

  • 조경진;김희대;이현조;심춘보;장재우
    • 한국콘텐츠학회논문지
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    • 제11권4호
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    • pp.101-111
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    • 2011
  • 최근 유무선 통신 기술의 발전 및 모바일 정보기기의 보편화에 힘입어, 시간과 장소에 제약 없이 서비스를 제공할 수 있는 유비쿼터스 컴퓨팅(Ubiquitous computing)기술이 각광받고 있다. 이에 따라, 무선 센서네트워크(Wireless Sensor Network: WSN) 기술과 상황인식(Context-awareness) 기술에 대한 관심이 크게 고조 되고 있으며, WSN과 상황인식을 접목하여 다양한 분야에서 활용할 수 있는 응용시스템의 개발이 활발하다. 하지만 기존 상황인식 기술을 WSN에 적용할 경우, 첫째, 불필요한 데이터를 전송하여 에너지효율성을 저하시키는 단점이 존재한다. 둘째, 새로운 응용 서비스를 구현할 경우, 특정 응용에 의존적이 기 때문에, 새로운 상황인식 모듈을 구현해야 하는 문제점이 있다. 이를 위해 본 연구에서는 무선 센서 네트워크에서 상황인식에 근거한 새로운 실시간 감시시스템을 제안한다. 제안하는 시스템은 센서노드에서 상황인식을 수행하여 불필요한 데이터 전송을 줄여 에너지 효율성을 높이고, 모듈화를 통해 새로운 상황인식 기능을 지원할 수 있는 확장성을 지닌다.

UWB 기반 위치인식 정확도 향상 기법 (Accuracy Improvement Scheme for Location Awareness based on UWB system)

  • 최영훈;배정남;김진영
    • 한국인터넷방송통신학회논문지
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    • 제11권2호
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    • pp.231-236
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    • 2011
  • 근래에 위치 정보를 이용하는 위치기반서비스는 많은 분야에서 이용되고 있다. 그에 따라 위치인식 기법들에 대해 많은 연구가 이루어지고 있다. 다양한 위치인식 시스템 중 TOA(Time of Arrival)이나 TDOA(Time Difference of Arrival)와 같은 시간 기반 위치인식 알고리즘을 사용하는 위치인식 시스템에서는 AWGN(Additive White Gaussian Noise)와 다중경로에 의한 왜곡이 위치인식 성능의 저하를 발생시킨다. 본 논문에서는 이런 성능 저하를 극복하기 위해서 여러 개의 펄스를 평균하는 방법으로 잡음을 제거한다. 그리고 임계값 설정을 통해 직선 경로 신호를 검출함으로써 위치인식 성능을 향상시키는 기법에 대해 연구하였다.

Use of gaze entropy to evaluate situation awareness in emergency accident situations of nuclear power plant

  • Lee, Yejin;Jung, Kwang-Tae;Lee, Hyun-Chul
    • Nuclear Engineering and Technology
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    • 제54권4호
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    • pp.1261-1270
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    • 2022
  • This study was conducted to investigate the possibility of using gaze entropy to evaluate an operator's situation awareness in an emergency accident situation of a nuclear power plant. Gaze entropy can be an effective measure for evaluating an operator's situation awareness at a nuclear power plant because it can express gaze movement as a single comprehensive number. In order to determine the relationship between situation awareness and gaze entropy for an emergency accident situation of a nuclear power plant, an experiment was conducted to measure situation awareness and gaze entropy using simulators created for emergency accident situations LOCA, SGTR, SLB, and LOV. The experiment was to judge the accident situation of nuclear power plants presented in the simulator. The results showed that situation awareness and Shannon, dwell time, and Markov entropy had a significant negative correlation, while visual attention entropy (VAE) did not show any significant correlation with situation awareness. The results determined that Shannon entropy, dwell time entropy, and Markov entropy could be used as measures to evaluate situation awareness.

지역사회 걷기 활성화를 위한 매체-캠페인이 걷기관련 인식과 행태변화에 미치는 영향 (Impact of a Media-Campaign to Promote Walking on Awareness & Behavior Change)

  • 안의수;이용수
    • 보건교육건강증진학회지
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    • 제24권4호
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    • pp.99-114
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    • 2007
  • Object: To analyze the effect of a media-campaign for "walking exercise participation improvement", which impacted walking-related awareness and behavior change of residents in Seoul. Method: This study used three campaign media including printing information, walking exercise indication board and a public advertisement of cable TV to lead a walking-related awareness change and practice frequency(number of days per week walking) and time(minutes per day walking) of walking exercise. To evaluate the exposure and message-recall levels of a campaign and effects of awareness change and walking practice, this study used a questionnaire survey(N=377). Result: 1) Group of exposure to campaign more participate and had the higher frequency(p=.015) and time(p=.023) in walking exercise and in comparison with group of nonexposure. 2) Group of changed awareness to campaign more participate and had the higher frequency and time in walking exercise and in comparison with group of no changed perception(p <.05). 3) Level of message recall of ${\ulcorner}$printing information${\lrcorner}$ was associated with number of days per week walking, and level of message recall of ${\ulcorner}$public advertisement of cable TV${\lrcorner}$ was associated with minutes per day walking at a statistically significant level(p <.05). Conclusion: These results suggest that media campaign can enhance the success of community-based efforts to promote awareness change and walking practice.

A CDN-P2P Hybrid Architecture with Location/Content Awareness for Live Streaming Services

  • Nguyen, Kim-Thinh;Kim, Young-Han
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제5권11호
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    • pp.2143-2159
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    • 2011
  • The hybrid architecture of content delivery networks (CDN) and peer-to-peer overlay networks (P2P) is a promising technology enables effective real-time streaming services. It complements the advantages of quality control and reliability in a CDN, and the scalability of a P2P system. With real-time streaming services, however, high connection setup and media delivery latency are becoming the critical issues in deploying the CDN-P2P system. These issues result from biased peer selection without location awareness or content awareness, and can lead to significant service disruption. To reduce service disruption latency, we propose a group-based CDN-P2P hybrid architecture (iCDN-P2P) with a location/content-aware selection of peers. Specifically, a SuperPeer network makes a location-aware peer selection by employing a content addressable network (CAN) to distribute channel information. It also manages peers with content awareness, forming a group of peers with the same channel as the sub-overlay. Through a performance evaluation, we show that the proposed architecture outperforms the original CDN-P2P hybrid architecture in terms of connection setup delay and media delivery time.

Awareness effects by aquapuncture with dexamethasone in tiletamine/zolazepam anesthetized dogs

  • Park, Hyung-Jin;Song, Kun-Ho;Kim, Duck-Hwan
    • 대한수의학회지
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    • 제51권4호
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    • pp.303-307
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    • 2011
  • Awareness effect of aquapuncture with dexamethasone on GV-26 was studied in tiletamine/zolazapam anesthetized six healthy crossbred dogs using a randomized cross-over experimental study design. After anesthesia by tiletamine/zolazapam, 0.1 mg dexamethasone was injected on GV-26 at 20 min in the experimental group. For the control group, 0.1 mg dexamethasone was injected on the quadriceps femoralis. A significant difference was evident in the sedation score between groups at 60 and 90 min (p < 0.05). A significant difference was also evident in the analgesia score at 50 and 60 min (p < 0.05). At 90 min, all dogs in the experimental group responded strongly to pain (p < 0.01). Head up time, sternal recumbent time, standing time, and walking time was shorter in the experimental group, but the difference from the control group was statistically significant only for head up time and walking time (p < 0.05). GV-26 acupuncture with dexamethasone is useful for awareness effects after anesthesia.

Development of a Reduction Algorithm of GEO Satellite Optical Observation Data for Optical Wide Field Patrol (OWL)

  • Park, Sun-youp;Choi, Jin;Jo, Jung Hyun;Son, Ju Young;Park, Yung-Sik;Yim, Hong-Suh;Moon, Hong-Kyu;Bae, Young-Ho;Choi, Young-Jun;Park, Jang-Hyun
    • Journal of Astronomy and Space Sciences
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    • 제32권3호
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    • pp.201-207
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    • 2015
  • An algorithm to automatically extract coordinate and time information from optical observation data of geostationary orbit satellites (GEO satellites) or geosynchronous orbit satellites (GOS satellites) is developed. The optical wide-field patrol system is capable of automatic observation using a pre-arranged schedule. Therefore, if this type of automatic analysis algorithm is available, daily unmanned monitoring of GEO satellites can be possible. For data acquisition for development, the COMS1 satellite was observed with 1-s exposure time and 1-m interval. The images were grouped and processed in terms of "action", and each action was composed of six or nine successive images. First, a reference image with the best quality in one action was selected. Next, the rest of the images in the action were geometrically transformed to fit in the horizontal coordinate system (expressed in azimuthal angle and elevation) of the reference image. Then, these images were median-combined to retain only the possible non-moving GEO candidates. By reverting the coordinate transformation of the positions of these GEO satellite candidates, the final coordinates could be calculated.

Understanding the Mapping Principle of One Syllable One Character as a Predictor of Word Reading Development in Chinese

  • Lin, Dan;Shiu, Ling-Po;Liu, Yingyi
    • Child Studies in Asia-Pacific Contexts
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    • 제6권2호
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    • pp.73-85
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    • 2016
  • Speech-print mapping awareness is defined as the awareness of the principles underpinning how speech sound is matched to print symbols. Chinese is unique in that it follows the one syllable one character mapping principle. The present study examined the predictive power of speech-print mapping awareness in young children's word reading. Seventy-four Hong Kong children from the first and second kindergarten years were tested with phonological awareness, visual skills, syllable-level mapping awareness, and Chinese reading ability at Time 1. Chinese reading abilities were tested again 1 year later. It was found that syllable-level mapping awareness predicted Chinese word reading abilities 12 months later. Further, it seemed that the link of syllable mapping to Chinese reading is particularly significant for beginning readers. The findings suggest that understanding the language-specific speech-print mapping principle is critical for reading acquisition at the early stage of reading development.

실시간 공간 상황 분석을 위한 공간 데이터 스트림 처리 시스템 (A Spatial Data Stream Processing System for Spatial Context Analysis in Real-time)

  • 권오제;김재훈;이기준
    • Spatial Information Research
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    • 제18권1호
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    • pp.69-76
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    • 2010
  • 센서로부터 획득되는 데이터 스트림들 중에 특히 이동 객체에 대한 공간 정보를 담은 데이터 스트림은 상황 인지의 여러 응용 분야에 매우 유용하다. 하지만, 실시간으로 공간 스트림을 처리하는 것과 공간 상황 인지를 위한 복잡한 연산 처리 사이에는 중요한 기능적인 격차가 존재하는데, 이는 공간 스트림 처리와 상황 인지를 통합하는데 매우 큰 어려움을 준다. 본 논문에서는, 공간 스트림 처리와 공간 상황 인지 사이에 존재하는 기능적인 격차를 해결하기 위한 공간 데이터 스트림 처리 시스템인 SCONSTREAM(Spatial CONtext STREAm Management)를 제안한다. 본 논문에서 제안하는 시스템은 불필요한 공간 데이터 스트림을 전처리하고 상황 인지에 용이한 형태로 가공한다. 실험을 통해, 본 시스템이 공간 스트림 처리와 공간 상황 인지 사이에 존재하는 기능적인 격차를 해소할 수 있음을 보인다.