• Title/Summary/Keyword: Imaging condition

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전자사진용 화상시스템의 화상개선 알고리즘 (Image Enhancement Algorithm in Imaging Systems for Electronic Photography)

  • 박용주;김지홍
    • 한국인쇄학회지
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    • 제20권1호
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    • pp.133-145
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    • 2002
  • 전자사진은 디지털 기술의 급속한 발전에 의하여 그 응용 범위가 확대되고있으나, 은염사진과 원리와 특성이 근본적으로 다르며 은염사진에 익숙한 사용자에게도 은염사진과 유사한 특성을 보이도록 화상의 개선과 화질의 보정 등이 요구된다. 본 논문은 은염사진의 계조 특성을 추출하여 전자화상시스템에 적용시켜 은염사진의 계조 특성을 지닌 전자화상을 출력하는 방법을 제시한다. 먼저, 은염사진과 전자사진의 화상 생성 공정을 구체적으로 비교하여 그 차이를 기술하고, 사진 계조 변환의 원리와 방법을 제시한다. 다음으로 사진 계조 변환함수를 구하기 위한 각 시스템의 특성화의 실험을 수행한 결과를 보인다. 최종적으로 이론을 바탕으로 한 실험에서는 사진 계조로 변환된 데이터를 디지털 화상시스템으로 출력하여 은염사진의 계조 특성의 비교분석을 수행한다.

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고온고압 환경에 노출된 영상장치 내열특성 (Thermal Characteristics of Imaging Device Exposed to High Temperature and High Pressure)

  • 신재익;안동찬;조재한
    • 한국추진공학회:학술대회논문집
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    • 한국추진공학회 2017년도 제48회 춘계학술대회논문집
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    • pp.1192-1195
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    • 2017
  • 본 논문은 엔진 시험시 엔진의 후단에 설치되어 엔진 내부의 상태를 감시하는 영상장치의 내열 특성에 관한 것으로, 엔진 시험설비에 사용되는 영상프로브 소개 및 개발에 관한 내용을 담고 있다. 엔진 후단의 영상장치는 고온고압 환경에 노출되어 있어서 장치형상 변경 및 냉각수 공급으로 장치의 안정성을 확보해야 한다. 국방과학연구소의 엔진 시험 장치의 후단에 영상프로브가 설치되어 있으며, 내열특성을 반영하여 설계하여 장치의 안정성을 확보하였다.

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초음파 혈관 영상의 상호적 영상 분할 (Interactive image segmentation for ultrasound vascular imaging)

  • 이언석;김민기;하승한
    • 한국융합학회논문지
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    • 제3권4호
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    • pp.15-21
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    • 2012
  • 초음파 영상 진단 장치에서 획득한 데이터로부터 진단 객체를 추출하기 위한 영상 분할은 질병의 효과적인 진단을 위하여 필수적인 전처리 과정으로 인식되고 있으며, 지금까지 많은 분할 기법들이 연구되고 있다. 본 연구에서는 혈관 초음파 영상의 다양한 응용 및 진단법 개발을 위하여 기초 전처리과정으로서 graph cut 알고리즘에 의한 상호적인 영상분할법을 제시한다. 일반영상 및 혈관 초음파 영상에 대하여 전경(foreground)과 배경(background)의 제약조건을 주고 영상분할 처리하여, 원하는 object에 대한 분할 결과를 얻었다. 향후, 이러한 일련의 처리 과정이 실시간으로 처리되면 새로운 초음파 진단법으로 발전시켜 나갈 수 있을 것으로 사료된다.

The role of cone-beam computed tomography in the radiographic evaluation of obstructive sleep apnea: A review article

  • Marco Isaac;Dina Mohamed ElBeshlawy;Ahmed ElSobki;Dina Fahim Ahmed;Sarah Mohammed Kenawy
    • Imaging Science in Dentistry
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    • 제53권4호
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    • pp.283-289
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    • 2023
  • The apnea-hypopnea index is widely regarded as a measure of the severity of obstructive sleep apnea (OSA), a condition characterized by recurrent episodes of apnea or hypopnea during sleep that induce airway collapse. OSA is a catastrophic problem due to the wide range of health issues it can cause, including cardiovascular disease and memory loss. This review was conducted to clarify the roles of various imaging modalities, particularly cone-beam computed tomography (CBCT), in the diagnosis of and preoperative planning for OSA. Unfortunately, 2-dimensional imaging techniques yield insufficient data for a comprehensive diagnosis, given the complex anatomy of the airway. Three-dimensional (3D) imaging is favored as it more accurately represents the patient's airway structure. Although computed tomography and magnetic resonance imaging can depict the actual 3D airway architecture, their use is limited by factors such as high radiation dose and noise associated with the scans. This review indicates that CBCT is a low-radiation imaging technique that can be used to incidentally identify patients with OSA, thereby facilitating early referral and ultimately enhancing the accuracy of surgical outcome predictions.

Intrasellar Schwannomas

  • Yoon, Wan-Soo;Park, Ik-Seong;Baik, Min-Woo
    • Journal of Korean Neurosurgical Society
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    • 제37권2호
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    • pp.157-159
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    • 2005
  • The authors present two cases of intrasellar schwannoma, a condition rarely reported in the literature. The patients presented with symptoms of hypopituitarism. Sellar magnetic resonance imaging(MRI) revealed intrasellar masses extending into the suprasellar region, with the normal pituitary gland also identifiable in the imaging study. The tumors were removed via trans-sphenoidal route, and found to be very firm, unlike usual pituitary adenomas. Tissue diagnosis confirmed the tumors as schwannoma.

Idiopathic Spinal Cord Herniation Presented as Brown-Sequard Syndrome : A Case Report and Surgical Outcome

  • Ju, Min-Wook;Choi, Seung-Won;Youm, Jin-Young;Kwon, Hyon-Jo
    • Journal of Korean Neurosurgical Society
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    • 제58권3호
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    • pp.294-297
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    • 2015
  • Spinal cord herniation is a rare condition that has become increasingly recognised in the last few years. The authors report a case of idiopathic spinal cord herniation in a 33 year old woman performed with progressive Brown-Sequard syndrome. The diagnosis was made on MR imaging. After repairing the herniation, the patient made a gradual improvement. Potential causes are discussed, including a possible role of dural defect. In conclusion, idiopathic spinal cord herniation is a potentially treatable condition that should be more readily diagnosed that increasing awareness and improved imaging techniques.

Posterior reversible encephalopathy syndrome caused by presumed Takayasu arteritis

  • Lee, Ki Wuk;Lee, Sang Taek;Cho, Heeyeon
    • Clinical and Experimental Pediatrics
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    • 제59권sup1호
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    • pp.145-148
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    • 2016
  • Takayasu arteritis (TA) is a chronic inflammatory disease of unknown etiology that affects mainly the aorta, main aortic branches, and pulmonary arteries. Diverse neurological manifestations of TA have rarely been reported in children. Posterior reversible encephalopathy syndrome (PRES) is a neuroradiological condition that presents with headache, seizure, visual disturbances, and characteristic lesions on imaging. Inflammatory condition and severe hypertension in TA can cause PRES. We report of a 5-year-old girl with presumed TA who presented with PRES and chronic total occlusion in the renal artery. The findings on magnetic resonance imaging suggested PRES. Left nephrectomy was performed for total occlusion of the left renal artery, and the confirmatory diagnosis of TA was based on the pathologic findings of the renal artery.

Neuroimaging and Clinicopathologic Findings of Lymphoplasmacyte-rich Meningioma, Mimicking Malignancy: Case Report

  • Lee, Moon Young;Ahn, Kookjin;Lee, Youn Soo;Jeun, Sin Soo
    • Investigative Magnetic Resonance Imaging
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    • 제19권1호
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    • pp.62-66
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    • 2015
  • Lymphoplasmacyte-rich meningioma is a rare WHO Grade I subtype of meningioma. The lymphoplasmacyte-rich meningioma does not have typical imaging features of a meningioma so it can mimic intracranial inflammatory condition or brain neoplasm. We report the clinicopathologic features of lymphoplasmacyte-rich meningioma in a 35-year-old woman. She suffered from progressive headache, dizziness and tinnitus over two years. The tumor exhibited atypical neuroimaging features, including obvious peritumoral edema and irregular enhancing components. She underwent total resection and histologic examination revealed a meningioma with numerous plasma cells. Her symptoms have since resolved and there has been no evidence of tumor recurrence after one year of follow-up.

뇌의 기능영상에 있어서 자화율효과와 혈류효과 연구 (Susceptibility Effects v.s Flow Effects in Functional MRI)

  • 박종배;정순철;박세혁;노용만;조장희
    • 대한의용생체공학회:학술대회논문집
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    • 대한의용생체공학회 1993년도 추계학술대회
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    • pp.23-26
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    • 1993
  • In MR functional imaging, it is shown that the signal change during photic activation is composed of two terms, i.e. the inflow effect and the susceptibility effect. Relatively the inflow effect affects the data obtained by CGE on the condition of short $T_E$(15ms) and large $\alpha$(90degree). The susceptibility effect, however, mainly contributes to the data on the condition of large $T_E$(35ms) and small $\alpha$(30degree). In this apper, we will discriminate the susceptibility effect for the intermingled data affected both flow effect and susceptibility effect. Finally susceptibility only functional imaging is proposed by using TRFGE.

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호모그래피 변환을 이용한 가시광 및 적외선 열화상 영상 정합 (Visible Light and Infrared Thermal Image Registration Method Using Homography Transformation)

  • 이상협;박장식
    • 한국산업융합학회 논문집
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    • 제24권6_2호
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    • pp.707-713
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    • 2021
  • Symptoms of foot-and-mouth disease include fever and drooling a lot around the hoof, blisters in the mouth, poor appetite, blisters around the hoof, and blisters around the hoof. Research is underway on smart barns that remotely manage these symptoms through cameras. Visible light cameras can measure the condition of livestock such as blisters, but cannot measure body temperature. On the other hand, infrared thermal imaging cameras can measure body temperature, but it is difficult to measure the condition of livestock. In this paper, we propose an object detection system using deep learning-based livestock detection using visible and infrared thermal imaging composite camera modules for preemptive response