• 제목/요약/키워드: Space scan

검색결과 261건 처리시간 0.02초

Pilot observations of VLBI fringe survey at 43 GHz using VERA

  • 오정환;이상성;;;;손봉원
    • 천문학회보
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    • 제36권2호
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    • pp.60.1-60.1
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    • 2011
  • We present the preliminary results of the pilot observations for the fringe survey at 43 GHz with the VLBI Exploration of Radio Astrometry (VERA). The main goals of the fringe survey are to establish a full list of phase calibrators for the VERA dual-beam astrometric observations, and for the KVN multi-frequency phase referencing observations. We performed two 24 hours experiments as a pilot observation to test the feasibility of the fringe survey. Each source from a list of 220 sources has been observed in one scan for 2 minutes. 67 sources were detected with the SNR threshold of 3.5. The correlated flux densities of the detected sources are presented in four ranges of projected baseline lengths.

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폐소공포증 환자의 핵의학 영상검사에 관한 연구 (Study of Nuclear medical imaging tests patient of Claustrophobia)

  • 강용길;홍진웅;양한준;박성수;이귀원;김긍식
    • 대한디지털의료영상학회논문지
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    • 제15권1호
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    • pp.55-59
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    • 2013
  • Patients who had claustrophobia tend to feel fear when they were scanned by an MRI, CT, PET-CT, or using a gamma camera scan. In this paper, claustrophobic patients were tested to find effective ways by changing patient's positions. For this paper, PET-CT scan in patients who had claustrophobia were used in the prone position. Prone position helped to maintain stable position and to get a h0igh quality of inspection without failure. Thus, as claustrophobic patients were requested taking prone position, they could feel comfortable. In a confined space, prone position for the claustrophobic patients who had a fear of the PET-CT examination would be expected to reduce the failure rate of inspection.

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건축물 실시간 원격 스캔을 위한 SLAM 시스템 개발 시 고려사항 (Considerations for Developing a SLAM System for Real-time Remote Scanning of Building Facilities)

  • 강태욱
    • 한국BIM학회 논문집
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    • 제10권1호
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    • pp.1-8
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    • 2020
  • In managing building facilities, spatial information is the basic data for decision making. However, the method of acquiring spatial information is not easy. In many cases, the site and drawings are often different due to changes in facilities and time after construction. In this case, the site data should be scanned to obtain spatial information. The scan data actually contains spatial information, which is a great help in making space related decisions. However, to obtain scan data, an expensive LiDAR (Light Detection and Ranging) device must be purchased, and special software for processing data obtained from the device must be available.Recently, SLAM (Simultaneous localization and mapping), an advanced map generation technology, has been spreading in the field of robotics. Using SLAM, 3D spatial information can be obtained quickly in real time without a separate matching process. This study develops and tests whether SLAM technology can be used to obtain spatial information for facility management. This draws considerations for developing a SLAM device for real-time remote scanning for facility management. However, this study focuses on the system development method that acquires spatial information necessary for facility management through SLAM technology. To this end, we develop a prototype, analyze the pros and cons, and then suggest considerations for developing a SLAM system.

시공간검정통계량을 이용한 도시범죄의 핫스팟분석 (Hotspot Analysis of Urban Crime Using Space-Time Scan Statistics)

  • 정경석;문태헌;정재희
    • 한국지리정보학회지
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    • 제13권3호
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    • pp.14-28
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    • 2010
  • 본 연구의 목적은 공간적 분포 특성만을 고려하고 있는 기존의 핫스팟분석에 대한 대안적인 방법으로서 공간상에서 나타나는 사건간의 인과관계를 시간영역으로까지 확장하여 동시적 분석이 가능한 시공간분석 방법을 제안하는 것이다. 분석방법으로는 먼저 지리정보시스템을 이용하여 지방중소도시인 M시의 범죄자료를 데이터화 하였고, Ripley K함수와 시공간검정통계량 분석을 통해 M시의 범죄분포 패턴을 지도화 하였다. 연구결과, 범죄위험도가 유의미하게 높은 지역들이 나타났으며, 이들 시공간적 범죄 집중지역들은 기존의 공간분포만을 고려한 범죄분포 패턴과는 다소 차이가 있음을 발견할 수 있었다. 본 연구결과는 시공간적인 범죄분포 특성에 맞는 맞춤형의 경찰 인력 배치와 배분, 그리고 치안행정 서비스 등의 조정을 위한 참고자료로서, 또한 시공간적인 집중을 보이는 이들 지역을 중심으로 물리적 환경 변화의 유도와 공간이용의 개선 효과를 통해 범죄율을 줄여나가는 범죄예방 활동 및 정책수립을 위한 기초자료로도 유용하게 활용될 수 있을 것으로 기대된다.

교양(膠樣) $^{198}$금(金) 혈액제거율검사(血液除去率檢査)의 간주사판독(肝走査判讀)에의 응용(應用) (An Application of Blood Clearance Rate of Colloidal $^{198}Au$ to the Interpretation of Photoscan of Liver)

  • 박용휘
    • 대한핵의학회:학술대회논문집
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    • 대한핵의학회 1966년도 제5회 학술대회
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    • pp.93.3-94
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    • 1966
  • The fact that colloidal particulates of rdaiogold are mainly and effectively eliminated from the blood stream by phagocytic activity of Kupffer's cells of the liver has been successfully adopted to the diagnosis if certain liver diseases and the same principle has opened a new avenue to the study of the organ by obtaining scan. Indeed, the latter procedure has been widely used for the detection of space-occupying lesions of cirrhosis of the liver. Nevertheless problem of differential diagnosis of monochromatic "cold" areas or "mottling" of the internal structure on the scan limited the value of this diagnostic modality. The present investigation is aimed at improving intepretation of photoscan findings with the aid of blood clearance rate of the intravenously injected colloidal $^{198}Au$.

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Distribution of Tropical Tropospheric Ozone Determined by the Scan-Angle Method applied to TOMS Measurements

  • Kim, Jae-H.;Na, Sun-Mi;Newchurch, M. J.;Emmons, L.
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2002년도 Proceedings of International Symposium on Remote Sensing
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    • pp.7-11
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    • 2002
  • This study introduces the first method that determines tropospheric ozone column directly from a space-based instrument. This method is based on the physical differences in the Total Ozone Mapping Spectrometer (TOMS) measurement as a function of its scan-angle geometry. Tropospheric ozone in September-October exhibits a broad enhancement over South America, the southern Atlantic Ocean, and western South Africa and a minimum over the central Pacific Ocean. Tropical tropospheric ozone south of the equator is higher than north of the equator in September-October, the southern burning season. Conversely, ozone north of the equator is higher in March, the northern burning season. Overall, the ozone over the southern tropics during September-October is significantly higher than over the northern tropics. Abnormally high tropospheric ozone occurs over the western Pacific Ocean during the El Nino season when the ozone amounts are as high as the ozone over the Africa.

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전치부 접촉과 측두하악 관절강폭과의 관계에 관한 연구 (A Study on the Relationship between Anterior Tooth Contact and Temporomandibular Joint Space)

  • Sang-Don Kim;Kyung-Soo Han;Min Shin
    • Journal of Oral Medicine and Pain
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    • 제18권2호
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    • pp.43-53
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    • 1993
  • The aim of this study was to investigate the relationship between the presence or absence of anterior tooth contact and the changes in temporomandibular joint space. The study sample consisted of 32symptom-free dental students and 79 craniomandibular disorders patients with unilateral joint dysfunction. The two groups were categorized into control group or experimental group, respectively. Recordings of the number and distribution of occlusal contacts were made by T-Scan system. Transcranial radiographs were taken with using of accurad-100 head positioner. Measured items in transcranial radiographs were anterior, superior, posterior joint space and relative condylar position to deepest position of glenoid folla. According to the presence or absence of anterior tooth contact, each group was subdivided and compared with each other with respect to TM joint space. Data were processed and tested with SPSS/PC + package. The results of the study showed that the joint space in control group were wider than those of experimental group and the difference of the width of joint space was more remarkable in subjects with anterior contact between control group and experimental group. However, in same group whether the presence of anterior tooth contact could hardly affect the difference of the width of joint space. And anterior tooth contact in grouip are more frequent than in experimental group.

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The Prognostic Factors Influencing on the Therapeutic Effect of Percutaneous Vertebroplasty in Treating Osteoporotic Vertebral Compression Fractures

  • Ryu, Kyeong-Sik;Park, Chun-Kun
    • Journal of Korean Neurosurgical Society
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    • 제45권1호
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    • pp.16-23
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    • 2009
  • Objective : This retrospective study of 215 patients with 383 symptomatic osteoporotic vertebral compression fractures (VCFs) treated by percutaneous vertebroplasty (PVP), was performed to evaluate the clinical outcomes, and to analyze the various clinical factors affecting these results. Methods : The authors assessed the clinical outcome under the criteria such as the pain improvement, activity, requirement of analgesics, and the patient's satisfaction, and determined the relation to various peri- and intra-operative factors, and postoperative imaging findings. Results : The outcome was determined as 84.2% in relief of pain, 72.0% in change in activity, 65.7% in analgesics use, and 84.7% of satisfaction rate. More severe focal back pain, high uptake bone scan, and the lower mean T-score were related to the better pain relief following PVP. The longer the duration between fracture and PVP, the less severe focal back pain, low uptake bone scan, and leakage of PMMA into the paravertebral space were related to the less improvement in activity. Female and low uptake bone scan showed a correlation with more analgesic use. The longer the duration between fracture and PVP, low uptake bone scan, and the higher the mean T-score were correlated with the less the patients satisfaction. Conclusion : Our study suggests that PVP may be more effective in the acute phase of VCFs, more severe focal pain, and far advanced osteoporosis on BMD. Leakage of PMMA into the paravertebral spcae also could be affecting the surgical results.

스캔 기반의 인터넷 웜 공격 탐지 및 탐지룰 생성 시스템 설계 및 구현 (Design and Implementation of a System to Detect Intrusion and Generate Detection Rule against Scan-based Internet Worms)

  • 김익수;조혁;김명호
    • 정보처리학회논문지C
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    • 제12C권2호
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    • pp.191-200
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    • 2005
  • 컴퓨터와 인터넷의 발달로 컴퓨터 사용자들은 유용한 정보를 쉽게 얻을 수 있게 되었다. 그러나 동시에, 시스템 불법 침입과 서비스 거부 공격에 의한 피해는 심각한 수준에 이르렀다. 특히 인터넷 웜을 통한 서비스 거부 공격은 컴퓨터와 네트워크 서비스를 무력화 시킬 수 있기 때문에 이에 대한 대처방안이 시급하다 할 수 있다. 지금까지 많은 침입 탐지 시스템들이 탐지룰을 기반으로 공격을 탐지해왔지만, 새롭게 등장하는 인터넷 월을 탐지하는데 한계가 있다. 본 논문에서는 인터넷 웜이 여러 호스트들을 감염시키기 위해 네트워크 스캔 작업을 한다는 점에 착안하여, 스캔 기반의 인터넷 웜 공격을 효과적으로 탐지하기 위한 침입 탐지 및 탐지룰 생성 시스템을 제안한다. 제안된 시스템은 탐지룰을 기반으로 인터넷 월 공격을 탐지하며, 탐지룰에 존재하지 않는 인터넷 웜에 의한 트래픽이 유입될 경우, 수집된 트래픽 정보를 통해 새로운 탐지룰을 생성하기 때문에 신종 인터넷 웜에 신속히 대응할 수 있다. 그리고 필요할 때만 패킷 데이터를 수집하기 때문에 시스템 부하와 디스크 사용량을 줄일 수 있다.

3차원 공간 스캔을 위한 ToF-Stereo 융합 센서 시스템 설계 (Design of ToF-Stereo Fusion Sensor System for 3D Spatial Scanning)

  • 이윤주;유선국
    • 스마트미디어저널
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    • 제12권9호
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    • pp.134-141
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    • 2023
  • 본 논문에서는 3차원 객체의 인식률을 높이고 객체 검출 품질이 보장되며, 환경에 강건한 3차원 공간 스캔용 ToF-Stereo 융합 센서 시스템을 제안한다. ToF-Stereo 센서 융합 시스템은 ToF 센서와 Stereo RGB 센서의 센싱 값을 융합하는 방식을 사용하며, 하나의 센서가 동작하지 않더라도 다른 하나의 센서를 이용하여 계속해서 객체를 검출해 나갈 수 있다. ToF 센서와 Stereo RGB 센서의 센싱 거리, 센싱 해상도, 빛 반사도 및 조도 등에 따른 품질이 달라지므로, 신뢰도 추정에 기반하여 센서의 기능을 조절할 수 있는 모듈을 두었다. ToF-Stereo 센서 융합 시스템은 ToF 센서와 Stereo RGB 센서의 센싱 값을 결합하고, 신뢰도를 추정한 후 신뢰도에 따라 센서의 기능을 조절하여 두 센싱 값을 융합하므로 3차원 공간 스캔의 품질을 향상할 수 있다.