• 제목/요약/키워드: obstruction detecting

검색결과 21건 처리시간 0.021초

레이저 레이더 센서를 이용한 건널목 지장물 검지장치의 기능시험 (Functional Testing of Level Crossing Obstruction Detecting System Using Laser Radar Sensor)

  • 신동호;백종현;최현영;김용규
    • 한국통신학회논문지
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    • 제39C권3호
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    • pp.307-315
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    • 2014
  • 기존의 건널목 지장물 검지장치는 선검지 방식으로 지장물을 검지하지 못하는 구간이 발생하며, 분산적인 기기설치로 인해 유지보수 비용 및 안전성 측면에서 문제가 되고 있다. 따라서 이러한 지장물 검지장치의 문제점을 해결하기 위해 레이저레이더 센서를 이용한 건널목 지장물 검지장치가 개발되었다. 본 논문에서는 개발된 레이저레이더 센서를 이용한 건널목 지장물 검지장치의 기능시험을 수행한 결과에 대해 설명하고 있다. 기능시험은 지장물 검지에 따른 센서부와 제어부의 정상작동 시험과 센서부와 제어부에 고장 발생 시 고장정보를 표시하는 시험으로 구성하여 수행하였다. 수행된 기능시험을 통해 레이저레이더 센서를 이용한 건널목 지장물 검지장치의 기능들이 모두 정상동작하는 것을 확인하였다.

철도건널목 지장물 검지를 위한 보판센서 연구 개발 (A Study on the Development of Panel Sensor for Obstruction Detecting at the Railway Level Crossing)

  • 김종기;류상환;유광균;조황;이기서;이재훈
    • 한국철도학회논문집
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    • 제9권2호
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    • pp.230-236
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    • 2006
  • For a short-term measurement to reduce an accident on a railroad crossing, it is necessary to find out the weakness and problems of existing equipment in the railroad transportation system. The analysis of railroad crossing accidents shows that main causes of accidents (24.9%) are the careless driving including an engine problem, damage on the safety equipment, slide on the snow, and an engine stop on the railroad crossing. Therefore, it is required to install a sensor, or to make a crossing gate at the exist for detecting obstacles on a railroad to prevent collisions among trains. This paper suggests 'a panel sensor using the strain gauge' to make up the weaknesses of the sensing Dead Zone, which are caused by using a laser method, and to detect any small objects passing railroads in order to reduce the errors, which are occurred in the earth magnetic field for controlling Exit Slide Crossing Arm Detector. The device, suggested in this paper, is verified with detecting any small objects passing the railroad, with judging entry decision clearly, and with controlling passing gate and obstruction warnings/cautions obstacles at the same time, through an experimental test.

레이저레이더 센서를 이용한 철도 건널목 지장물 검지 알고리즘 개발 (Algorithm Development of Level Crossing Obstacle Detection using Laser Radar Sensor)

  • 김영준;백종현;최규형
    • 전기학회논문지
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    • 제62권12호
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    • pp.1813-1819
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    • 2013
  • Existing level crossing obstacle detecting system was installed using a laser beam. Level crossing obstacle detecting system using a laser beam that has been a problem in relation to safety and maintainability failure according to weather conditions. We proposed laser radar level crossing obstacle detecting system as a way to overcome problem, and we developed an algorithm for this. Level crossing obstacle detecting system using a laser radar sensor algorithm is robust to external environment and a shadow zone does not exist. Sensor part of the laser radar level crossing obstacle detecting system of these is made up by the image processing unit and laser radar sensor, it operations by receiving train entering information from the control unit. In this paper, we proposed a detecting algorithm with calculation of the size of the laser radar sensor. Based on this, we were performance test on the basis of the scenario by making a prototype. In the future, laser radar level crossing obstacle detecting system to ensure the safety and reliability through the field test.

Quantitative T1 Mapping for Detecting Microvascular Obstruction in Reperfused Acute Myocardial Infarction: Comparison with Late Gadolinium Enhancement Imaging

  • Jae Min Shin;Eui-Young Choi;Chul Hwan Park;Kyunghwa Han;Tae Hoon Kim
    • Korean Journal of Radiology
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    • 제21권8호
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    • pp.978-986
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    • 2020
  • Objective: To compare native and post-contrast T1 mapping with late gadolinium enhancement (LGE) imaging for detecting and measuring the microvascular obstruction (MVO) area in reperfused acute myocardial infarction (MI). Materials and Methods: This study included 20 patients with acute MI who had undergone 1.5T cardiovascular magnetic resonance imaging (CMR) after reperfusion therapy. CMR included cine imaging, LGE, and T1 mapping (modified look-locker inversion recovery). MI size was calculated from LGE by full-width at half-maximum technique. MVO was defined as an area with low signal intensity (LGE) or as a region of visually distinguishable T1 values (T1 maps) within infarcted myocardium. Regional T1 values were measured in MVO, infarcted, and remote myocardium on T1 maps. MVO area was measured on and compared among LGE, native, and post-contrast T1 maps. Results: The mean MI size was 27.1 ± 9.7% of the left ventricular mass. Of the 20 identified MVOs, 18 (90%) were detected on native T1 maps, while 10 (50%) were recognized on post-contrast T1 maps. The mean native T1 values of MVO, infarcted, and remote myocardium were 1013.5 ± 58.5, 1240.9 ± 55.8 (p < 0.001), and 1062.2 ± 55.8 ms (p = 0.169), respectively, while the mean post-contrast T1 values were 466.7 ± 26.8, 399.1 ± 21.3, and 585.2 ± 21.3 ms, respectively (p < 0.001). The mean MVO areas on LGE, native, and post-contrast T1 maps were 134.1 ± 81.2, 133.7 ± 80.4, and 117.1 ± 53.3 mm2, respectively. The median (interquartile range) MVO areas on LGE, native, and post-contrast T1 maps were 128.0 (58.1-215.4), 110.5 (67.7-227.9), and 143.0 (76.7-155.3) mm2, respectively (p = 0.002). Concordance correlation coefficients for the MVO area between LGE and native T1 maps, LGE and post-contrast T1 maps, and native and post-contrast T1 maps were 0.770, 0.375, and 0.565, respectively. Conclusion: MVO areas were accurately delineated on native T1 maps and showed high concordance with the areas measured on LGE. However, post-contrast T1 maps had low detection rates and underestimated MVO areas. Collectively, native T1 mapping is a useful tool for detecting MVO within the infarcted myocardium.

Surgical Complications Affecting the Early and Late Survival Rates after Lung Transplantation

  • Suh, Jee Won
    • Journal of Chest Surgery
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    • 제55권4호
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    • pp.332-337
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    • 2022
  • Since the first lung transplantation in humans was performed in 1963, patient selection, standardized procurement, and surgical techniques have been developed and established for this procedure. However, despite these developments, surgical complications continue to be important factors influencing patient morbidity and mortality, and efforts should be made to decrease morbidity and improve survival rates by understanding, rapidly detecting, and appropriately treating surgical complications.

영상해석을 통한 철도건널목 장애물 검지방법 개선 (Improvement of Obstruction Detecting Method at Railroad Crossing by Image Analyze)

  • 송현삼;김영달;이대동;심재명
    • 전기학회논문지
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    • 제60권7호
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    • pp.1444-1450
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    • 2011
  • An analysis of the causes of railroad crossing accidents reveals that most train collision accidents that occur when safety crossing devices are functioning normally occur because vehicles either experience engine failure on the tracks or because drivers were not notified of the coming train, in which case they get trapped on the tracks when the crossing barriers descend. To prevent such an accident, obstacle detection device by using laser beams detecting the presence of obstacle and crossing bar direction controller by moving direction detection sensor using the Earth's magnetic field detection technology are used in the railroad crossing. Despite using the obstacles detector and crossing bar direction controller in the railroad crossing, the equipments for the railroad crossing does not prevent accidents completely. Therefore, this research has studied new method that can detect obstacles through image analyze and alternate existing equipments. There will be excellent effect to be preventing railroad crossing accident by developing a reliable and new obstacle detecting device.

Usefulness of MR Imaging for Diseases of the Small Intestine: Comparison with CT

  • Ji-Hoon Kim;Hyun Kwon Ha;Min Jee Sohn;Byung Suck Shin;Young Suk Lee;Soo Yoon Chung;Pyo Nyun Kim;Moon-Gyu Lee;Yong-Ho Auh
    • Korean Journal of Radiology
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    • 제1권1호
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    • pp.43-50
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    • 2000
  • Objective: To evaluate the usefulness of MR imaging for diseases of the small intestine, emphasizing a comparison with CT. Materials and Methods: Thirty-four patients who underwent both CT and MR imaging using FLASH 2D and HASTE sequences were analyzed. All patients had various small bowel diseases with variable association of peritoneal lesions. We compared the detectabilities of CT and MR imaging using different MR pulse sequences. The capability for analyzing the characteristics of small intestinal disease was also compared. Results: MR imaging was nearly equal to CT for detecting intraluminal or peritoneal masses, lesions in the bowel and mesentery, and small bowel obstruction, but was definitely inferior for detecting omental lesions. The most successful MR imaging sequence was HASTE for demonstrating bowel wall thickening, coronal FLASH 2D for mesenteric lesions, and axial FLASH 2D for omental lesions. MR imaging yielded greater information than CT in six of 12 inflammatory bowel diseases, while it was equal to CT in six of seven neoplasms and inferior in five of seven mesenteric ischemia. In determining the primary causes of 15 intestinal obstructions, MR imaging was correct in 11 (73%) and CT in nine (60%) patients. Conclusion: MR imaging can serve as an alternative diagnostic tool for patients with suspected inflammatory bowel disease, small intestinal neoplasm or obstruction.

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Acute Airway Obstruction Secondary to Lingual Hematoma after Lower Third Molar Extraction: A Case Report

  • Yi, Sangmin;Oh, Je-Seok;Youn, Gap-Hee;Chung, Kwang;Jung, Seunggon;Park, Hong-Ju;Oh, Hee-Kyun;Kook, Min-Suk
    • Journal of Korean Dental Science
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    • 제7권1호
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    • pp.43-47
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    • 2014
  • Few dental procedures are potentially life-threatening. Note, however, that a dental extraction can result in preventable death. Severe post-extraction bleeding can occur, which may give rise to an alarming situation if there is any delay in detecting and managing the problem. The most immediate danger for a healthy patient with severe post-extraction hemorrhage is airway compromise. Acute airway obstruction from post-extraction hematoma is relatively uncommon, but it may occur with fatal consequences if there is any reluctance to maintain the airway clearance. Therefore, dentists and oral and maxillofacial surgeons should have clear understanding of the problem and measures to control it. Active bleeding that is not controlled by local measures in a dental office should be referred to the nearest hospital emergency department as soon as possible for appropriate management.

Identification of Pancreatic Cancer in Biliary Obstruction Patients by FRY Site-specific Methylation

  • Angsuwatcharakon, Phonthep;Rerknimitr, Rungsun;Kongkam, Pradermchai;Ridtitid, Wiriyaporn;Ponauthai, Yuwadee;Srisuttee, Ratakorn;Kitkumthorn, Nakarin;Mutirangura, Apiwat
    • Asian Pacific Journal of Cancer Prevention
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    • 제17권9호
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    • pp.4487-4490
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    • 2016
  • Background: Methylation at cg 16941656 of FRY is exclusively found in normal pancreatic tissue and has been proven to be specific for pancreatic-in-origin among several adenocarcinomas. Here, we investigated methylated DNA in the bile as a biomarker to differentiate the cause of obstruction between pancreatic cancer and benign causes. Materials and Methods: Bile samples of 45 patients with obstructive jaundice who underwent ERCP were collected and classified into pancreatic cancer (group 1) and benign causes (group 2) in 24 and 21 patients, respectively. DNA was extracted from bile and bisulfite modification was performed. After, methylation in cg 16941656 of FRY was identified by real-time PCR, with beta-actin used as a positive control. Results: Methylated DNA was identified in 10/24 (41.67%) and 1/21 (4.8%) of cases in groups 1 and 2, respectively (P= 0.012). The sensitivity, specificity, positive predictive value and negative predictive value to differentiate pancreatic cancer from benign causes were 42%, 95%, 91%, and 59%, respectively. Conclusions: Detecting a methylation at cg 16941656 of FRY in bile has high specificity, with an acceptable positive likelihood rate, and may therefore be helpful in distinguish pancreatic cancer from benign strictures.

도로사면의 국부적 위험요인 검지를 위한 이동형 장비 개발 (Development of Mobile Equipment for Local Risk Factors Detecting of Road Slope)

  • 김용수;정수정;안상로
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2008년도 추계 학술발표회
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    • pp.938-945
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    • 2008
  • Rockfall and landslide bring about a great social loss with loss of property such as obstruction of traffic and damage of the crops as well as casualty. The purpose of this study is to develop a mobile equipment for local risk factors detecting of road slope. The mobile equipment is designed to receive the sensing data from the measurement sensors, which are installed to detect the dangerous signs from the slopes, as loaded on a vehicle which is moving around to the places where the sensors are installed. In general, more than one mandatory data logger, which is very expensive, must be installed at each slope for the automatic measuring system, but in case of this developmental system, the inexpensive routine measurement can be performed regardless of the number of slopes due to the single unit of information gathering vehicle. This study is going to develop technologies that are expected to be applied to not only slope but also tunnel and bridges which might have the partial risk and need measuring.

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