• Title/Summary/Keyword: Scan Mechanism

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Evolution of Chronic Subdural Hematoma based on Brain CT findings and Appropriate Treatment Methods (만성 경막하 혈종의 성장에 대한 뇌 CT 소견 및 치료 방침)

  • Lee, Young Bae
    • Journal of Trauma and Injury
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    • v.25 no.4
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    • pp.209-216
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    • 2012
  • Purpose: The objectives of this study are to classify chronic subdural hematomas based on brain computerized tomographic scan (CT scan) findings and to determine the mechanism of evolution and treatment methods. Methods: One hundred thirty-nine patients who were diagnosed with a chronic subdural hematoma and who available for follow up assessment 6 months post-surgery were analyzed retrospectively. The presence of trauma and past medical history were reviewed and evaluation criteria based on brain CT scan findings were examined. Results: Initial brain CT scans revealed a chronic subdural hematoma in 106 patients, a subdural hygroma in 24 patients, and an acute subdural hematoma in 9 patients. In all cases where the initial acute subdural hematoma had progressed to a chronic subdural hematoma, final was a hypo-density chronic subdural hematoma. In case where the initial subdural hygroma had progressed to a chronic subdural hematoma, the most cases of hematoma were hyper-density and mixed-density chronic subdural hematoma. In total, 173 surgeries were performed, and they consisted of 97 one burr-hole drainages, 70 two burr-hole drainages and 6 craniotomies. Conclusion: This study demonstrates that rebleeding and osmotic effects are mechanisms for enlarging of a chronic subdural hematoma. In most cases, one burr-hole drainage is a sufficient for treatment. However, in cases of mixed or acute-on-chronic subdural hematomas, other appropriate treatment strategies are required.

In-Situ Spectroelectrochemical Studies of Manganese(II) Oxidation

  • Zhang, Haiyan;Park, Su-Moon
    • Analytical Science and Technology
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    • v.8 no.4
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    • pp.569-574
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    • 1995
  • In-situ spectroelectrochemical studies have been carried out on the oxidation of Mn(II) at platinum, gold, lead dioxide, and bismuth doped lead dioxide electrodes. The Mn(III), $MnO_2$, and/or ${MnO_4}^-$ species are produced depending on experimental conditions employed during electrolysis. Mn(III) is shown to be produced from a very early stage during the anodic potential scan and undergo disproportionation-conproportionation reactions depending on the relative concentration of each species near the electrode surface. An oxidation mechanism consistent with these observations is proposed.

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Helical Scan Grinding Mechanism of Double- mesh Wheel (입도 복합 숫돌의 헬리컬 스캔 연삭 기구)

  • 김한섭;박규열
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2000.05a
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    • pp.846-849
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    • 2000
  • 세라믹 재료는 높은 강도 및 결도를 갖는 기계적 성질로 인하여 연삭가공에는 다이아몬드를 지립으로 하는 초지립 숫돌이 사용된다. 다이아몬드는 일반지립에 비하여 내마모성이 월등하게 높다는 사실로부터 숫돌의 트루잉 및 드레싱 작업이 극히 곤란한 것은 주지의 사실이다.(중략)

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Rotating-Gantry-Based X-Ray Micro-Tomography System with the Sliding Mechanism Capable of Zoom-In Imaging

  • Cho, Min-Hyoung;Lee, Dong-Hun;Han, Byung-Hee;Lee, Soo-Yeol
    • Journal of Biomedical Engineering Research
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    • v.29 no.2
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    • pp.107-113
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    • 2008
  • We introduce a rotating-gantry-based x-ray micro-tomography system to be used for small animal imaging studies. It has the zoom-in imaging capability for high resolution imaging of a local region inside the animal subject without any contrast anomalies arising from truncation of the projection data. With the sliding mechanism mounted on the rotating gantry holding the x-ray source and the x-ray detector, we can control the magnification ratio of the x-ray projection data. By combining the projection data from the large field of view (FOV) scan of the whole animal subject and the projection data from the small FOV scan of the region of interest, we can obtain artifact-free zoomed-in images of the region of interest. For the acquisition of x-ray projection data, we use a $1248{\times}1248$ flat-panel x-ray detector with the pixel pitch of 100 mm. It has been experimentally found that the developed system has the spatial resolution of up to 121p/mm when the highest magnification ratio of 5:1 is applied to the zoom-in imaging. We present some in vivo rat femur images to demonstrate utility of the developed system for small animal imaging.

Utility of Spinal Injury Diagnosis Using C-Spine Lateral X-Ray and Chest, Abdomen and Pelvis Computed Tomography in Major Trauma Patients with Impaired Consciousness

  • Jang, Yoon Soo;So, Byung Hak;Jeong, Won Jung;Cha, Kyung Man;Kim, Hyung Min
    • Journal of Trauma and Injury
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    • v.31 no.3
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    • pp.151-158
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    • 2018
  • Purpose: The regional emergency medical centers manage the patients with major blunt trauma according to the process appropriate to each hospital rather than standardized protocol of the major trauma centers. The primary purpose of this study is to evaluate the effectiveness and influence on prognosis of additional cervical-thoracic-lumbar-spine computed tomography (CTL-spine CT) scan in diagnosis of spinal injury from the victim of major blunt trauma with impaired consciousness. Methods: The study included patients visited the urban emergency medical center with major blunt trauma who were over 18 years of age from January 2013 to December 2016. Data were collected from retrospective review of medical records. Sensitivity, specificity, positive predictive value, and negative predictive value were measured for evaluation of the performance of diagnostic methods. Results: One hundred patients with Glasgow coma scale ${\leq}13$ underwent additional CTL-spine CT scan. Mechanism of injury was in the following order: driver, pedestrian traffic accident, fall and passenger accident. Thirty-one patients were diagnosed of spinal injury, six of them underwent surgical management. The sensitivity of chest, abdomen and pelvis CT (CAP CT) was 72%, specificity 97%, false positive rate 3%, false negative rate 28% and diagnostic accuracy 87%. Eleven patients were not diagnosed of spinal injury with CAP CT and C-spine lateral view, but all of them were diagnosed of stable fractures. Conclusions: C-spine CT scan be actively considered in the initial examination process. When CAP CT scan is performed in major blunt trauma patients with impaired consciousness, CTL-spine CT scan or simple spinal radiography has no significant effect on the prognosis of the patient and can be performed if necessary.

Zoom-in X-ray Micro Tomography System

  • Chun, In-Kon;Lee, Sang-Chul;Park, Jeong-Jin;Cho, Min-Hyoung;Lee, Soo-Yeol
    • Journal of Biomedical Engineering Research
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    • v.26 no.5
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    • pp.295-300
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    • 2005
  • We introduce an x-ray micro tomography system capable of high resolution imaging of a local region inside a small animal. By combining two kinds of projection data, one from a full field-of-view (FOV) scan of the whole body and the other from a limited FOV scan of the region of interest, we have obtained zoomed-in images of the region of interest without any contrast a nomalies. We have integrated a micro tomography system using a micro-focus x-ray source, a $1248\times1248$ flat-panel x-ray detector, and a precision scan mechanism. Using the cross-sectional images taken with the zoom-in micro tomography system, we measured trabecular thicknesses of femur bones in postmortem rats. To compensate the limited spatial resolution in the zoom-in micro tomography images, we used the fuzzy distance transform for the calculation of the trabecular thickness. To validate the trabecular thickness measurement with the zoom-in micro tomography images, we compared the measurement results with the ones obtained from the conventional micro tomography images of the extracted bone samples.

Meningioma with Intratumoral Hemorrhage - A Case Report - (종양내 출혈을 동반한 뇌수막종 - 증례보고 -)

  • Chun, Sae Myoung;Kim, Tae Sung;Yee, Gi Taek;Koh, Jun Seok;Lim, Young Jin;Kim, Gook Ki;Leem, Won;Rhee, Bong Arm
    • Journal of Korean Neurosurgical Society
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    • v.30 no.9
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    • pp.1134-1139
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    • 2001
  • Meningioma associated with intratumoral hemorrhage is rarely reported. We present two patients with intratumoral hemorrhage. One 70-year-old man was admitted to our department with a decreased level of consciousness and left hemiparesis. CT scan and MRI scan revealed huge tumor with intratumoral hemorrhage in the frontal lobe. After surgical removal of the tumor, histopathological diagnosis was a meningotheliomatous meningioma. The other seemed patients was 56-year-old woman with headache and vomiting. She showed no specific neurological deficit. CT and MRI scan revealed large size tumor with intratumoral hemorrhage that looks like meningioma. The patient died suddenly before surgery. We reviewed the relevant literature and discussed the possible mechanism of hemorrhage in the meningioma.

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Development of Simple Reconfigurable Access Mechanism for SoC Testing (재구성 가능한 시스템 칩 테스트 제어기술의 개발)

  • 김태식;민병우;박성주
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.41 no.8
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    • pp.9-16
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    • 2004
  • For a System-on-a-Chip(SoC) comprised of multiple IP cores, test control techniques have been developed to perform the internal and external test efficiently relying on the various design for testability techniques such as scan and BIST(Built-In Self-Test). However the test area overhead is too expensive to guarantee diverse test link configurations. In this paper, at first we introduce a new flag based Wrapped Core Linking Module(WCLM) that enables systematic integration of IEEE 1149.1 TAP'd cores and P1500 wrapped cores. Then a simple test control technique, which can interconnect internal scan chains of different cores, is described with requiring least amount of area overhead compared with other state-of-art techniques. The design preserves compatibility with standards and scalability for hierarchical access.

Design and Implementation of Low-power CSD Considering Beacon Period and Channel Scan Time (비컨 주기와 채널 탐색기간을 고려한 저전력 CSD의 설계 및 구현)

  • Kim, Taek-Hyun;Park, Se-Young;Choi, Hoon;Baek, Yun-Ju
    • Journal of KIISE:Computing Practices and Letters
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    • v.16 no.1
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    • pp.50-54
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    • 2010
  • A Container Security Device (CSD) which is different existing RFID Tag strengthens the physical security as mounted inside the container and the information security as encrypts doubly a data. CSD must use the resources efficiently in order to operate with the battery. Therefore, it needs low-power mechanism which repeats the sleep period and channel scan period. However, by adjusting these periods, the trade-off occurs between energy efficiency and network connectivity. In this paper, we implement low-power CSD and resolve this problem by adjusting beacon period and channel scan time. As a result, We guarantee the network connectivity 95% or more and maximum life up to 16 days using common AA batteries.