• 대한족부족관절학회지
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• 제14권2호
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• pp.119-122
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• 2010

Purpose: One of the main contributors to proximal fifth metatarsal fracture is ankle inversion and the incidence of recurrence may increase in patients with ankle instability. So, the authors confirmed the patients of proximal fifth metatarsal fracture with ankle instability by checking the history and magnetic resonance imaging (MRI) and assessed the value of MRI as therapeutic prognosis and clinical indicators for prevention of recurrence. Materials and Methods: Patients with proximal fifth metatarsal fractures visited our hospital during recent five years were reviewed. 35 patients with suspected damage by ankle inversion had been identified a history of ankle instability and checked the hindfoot malalignment through hindfoot alignment view and MRI was performed prospectively. The patients was devided to three groups on the location of fracture site and the groups were compared each other. Results: The mean time from injury to checking MRI was 10.7 days. There was no structural abnormality and was no significant difference according to the location of fracture. The patients with history of ankle inversion were 31(88.6%) and the patients with history of chronic or recurrent injury were 22 patients (62.9%). The lesion of MRI related to lateral ankle instability were identified in all patients. Conclusion: This study noted a high incidence of lateral ankle instability that was identified by MRI in the patients of proximal fifth metatarsal fracture. Aggressive treatment for lateral ankle instability should be needed for complications as proximal fifth metatarsal fracture to reduce the recurrence and occurrence.

• 대한자기공명의과학회:학술대회논문집
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• 대한자기공명의과학회 2001년도 제6차 학술대회 초록집
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• pp.172-172
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• 2001

Purpose： To evaluate compensatory change of opposite hippocampus after temporal lobe surgery in th patient with temporal lobe epilepsy by using single-voxel proton MR spectroscopy. Method： Eighteen patients with intractable temporal lobe epilepsy (TLE) whose MR diagnos was unilateral hippocampal sclerosis (n=11) or localized unilateral anterior temporal lobe lesio (n=7) and who underwent anterior temporal lobectomy were included in the study. Singl proton MRS of opposite hippocampus was carried out on the same day or within 1 week af MR imaging before temporal lobe surgery and after over 1-year post-surgical follow-u Single voxel proton MRS were acquired using GE signa 1.5T scanner and spectrosco system (TR, 1500-2, 000： TE, 136-144). Region of interest (ROI) was placed in a simitar position for all examination to cover the medial temporal lobes including most of the head an body of hippocampus and a part of amygdala, the parahippocampal gyrus. The MR spectr were evaluated with a focus on the metabolite ratio of N-acetylaspartate (NAA choline-containing phospholipids (Cho), creatine (Cr). The metabolite ratios of NAA/ Cr were calculated from the relative peak height measurement. We evaluated change of th intensity ratio NAA/Cr between before and after surgery, to simplify quantification acro patients, because observed decreases in the ratio of NAA/Cr can be interpreted in terms o neuronal or axonal damage.

• Clinical and Experimental Pediatrics
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• 제54권5호
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• pp.212-218
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• 2011

Purpose: The diagnosis of acute pyelonephritis (APN) is often difficult, as its clinical and biological manifestations are non-specific in children. If not treated quickly and adequately, however, APN may cause irreversible renal damage, possibly leading to hypertension and chronic renal failure. We were suspecting the diagnostic value of $^{99m}Tc$-dimercaptosuccinic acid (DMSA) scan by experiences and so compared the results of DMSA scan to those of multi-detector row computed tomography (MDCT). Methods: We retrospectively selected and analyzed 81 patients who were diagnosed as APN by MDCT during evaluation of their acute abdomen in emergency room and then received DMSA scan also for the diagnostic work-up of APN after admission. We evaluated the results of imaging studies and compared the diagnostic value of each method by age groups, <2 years (n=45) and ${\geq}$2 years (n=36). Results: Among total 81 patients with MDCT-proven APN, DMSA scan was diagnostic only in 55 children (68%), while the remaining 26 children (32%) showed false negative normal findings. These 26 patients were predominantly male and most of them, 19 (73.1%) were <2 years of age. Conclusion: DMSA scan holds obvious limitation compared to MDCT in depicting acute inflammatory lesions of kidney in children with APN, especially in early childhood less than 2 years of age. MDCT showed hidden lesions of APN, those were undetectable through DMSA scan in children.

• 한국인터넷방송통신학회논문지
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• 제20권2호
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• pp.39-44
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• 2020

악성코드는 탐지 프로그램을 피해 기기들에게 피해를 유발한다. 기존의 악성코드 탐지 기법으로 이러한 새로운 악성코드를 탐지하는데 어려움을 겪는 이유는 서명 기반의 탐지 기법을 사용하기 때문이다. 이 기법은 기존 악성코드들은 효과적으로 탐지하지만, 새로운 악성코드에 대해서는 탐지가 어렵다. 이러한 문제점을 인식하여, 휴리스틱 기법을 추가적으로 사용한다. 이 논문에서는 딥러닝을 활용하여 악성코드를 탐지하는 기술에 대해 소개하여 새로운 악성코드를 탐지하는 기술에 대해서 제안한다. 또한, 악성코드를 탐지한다는 것은, 기기에서 실행 가능한 파일의 개수는 무수히 많으므로, 지도학습 방식(Supervisor Learning)으로는 분명한 한계가 존재한다. 그렇기 때문에, 준지도 학습으로 알려진 SCAE(Stacked Convolution AutoEncoder)를 활용한다, 파일들의 바이트 정보들을 추출하여, 이미지화를 진행하고, 이 이미지들을 학습을 시켜, 학습 시키지 않은 10,869개의 악성코드, 3,442개의 비악성코드를 모델에 추론한 결과 정확도를 98.84%을 달성하였다.

• Smart Structures and Systems
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• 제26권5호
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• pp.657-666
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• 2020

A rotational pulse-echo ultrasonic propagation imager that can inspect cylindrical specimens for material nondestructive evaluations is proposed herein. In this system, a laser-generated ultrasonic bulk wave is used for inspection, which enables a clear visualization of subsurface defects with a precise reproduction of the damage shape and size. The ultrasonic waves are generated by a Q-switched laser that impinges on the outer surface of the specimen walls. The generated waves travel through the walls and their echo is detected by a Laser Doppler Vibrometer (LDV) at the same point. To obtain the optimal Signal-to-Noise Ratio (SNR) of the measured signal, the LDV requires the sensed surface to be at a right angle to the laser beam and at a predefined constant standoff distance from the laser head. For flat specimens, these constraints can be easily satisfied by performing a raster scan using a dual-axis linear stage. However, this arrangement cannot be used for cylindrical specimens owing to their curved nature. To inspect the cylindrical specimens, a circular scan technology is newly proposed for pulse-echo laser ultrasound. A rotational stage is coupled with a single-axis linear stage to inspect the desired area of the specimen. This system arrangement ensures that the standoff distance and beam incidence angle are maintained while the cylindrical specimen is being inspected. This enables the inspection of a curved specimen while maintaining the optimal SNR. The measurement result is displayed in parallel with the on-going inspection. The inspection data used in scanning are mapped from rotational coordinates to linear coordinates for visualization and post-processing of results. A graphical user interface software is implemented in C++ using a QT framework and controls all the individual blocks of the system and implements the necessary image processing, scan calculations, data acquisition, signal processing and result visualization.

• 한국방사선학회논문지
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• 제12권2호
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• pp.253-260
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• 2018

비흡연자와 한국형 알코올 선별 검사법 (AUDIT-K)설문지 척도점수에 따라 적정음주군(10점 이하)을 연구대상으로 하여 뇌 백질의 손상 유무를 파악 할 수 있는 확산텐서영상을 검사하고 영상을 획득 한 후 Tract-Based Spatial Statics(TBSS)방법으로 뇌 백질 부위의 신경섬유로의 비등방도 FA(fractional anisotropy)값을 측정 분석한 결과 연령과 체질량지수(BMI)의 변인에 따른 뇌 백질 모든 영역에서 FA값은 통계적으로 유의하지 않았으며 본 연구의 결과 값으로 추측하자면 즉, 연령과 체질량지수(BMI)는 뇌 백질의 미세구조성 변화에 크게 영향을 미치지는 않는다고 할 수 있다.

• The Plant Pathology Journal
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• 제32권4호
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• pp.300-310
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• 2016

Pathogen infection in plants induces complex responses ranging from gene expression to metabolic processes in infected plants. In spite of many studies on biotic stress-related changes in host plants, little is known about the metabolic and phenotypic responses of the host plants to Pseudomonas cichorii infection based on image-based analysis. To investigate alterations in tomato plants according to disease severity, we inoculated plants with different cell densities of P. cichorii using dipping and syringe infiltration methods. High-dose inocula (${\geq}10^6cfu/ml$) induced evident necrotic lesions within one day that corresponded to bacterial growth in the infected tissues. Among the chlorophyll fluorescence parameters analyzed, changes in quantum yield of PSII (${\Phi}PSII$) and non-photochemical quenching (NPQ) preceded the appearance of visible symptoms, but maximum quantum efficiency of PSII ($F_v/F_m$) was altered well after symptom development. Visible/near infrared and chlorophyll fluorescence hyperspectral images detected changes before symptom appearance at low-density inoculation. The results of this study indicate that the P. cichorii infection severity can be detected by chlorophyll fluorescence assay and hyperspectral images prior to the onset of visible symptoms, indicating the feasibility of early detection of diseases. However, to detect disease development by hyperspectral imaging, more detailed protocols and analyses are necessary. Taken together, change in chlorophyll fluorescence is a good parameter for early detection of P. cichorii infection in tomato plants. In addition, image-based visualization of infection severity before visual damage appearance will contribute to effective management of plant diseases.

• 한국화재소방학회논문지
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• 제30권1호
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• pp.49-56
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• 2016

본 논문에서는 동절기 소방배관의 동파방지를 위한 열선의 직선 시공과 감기 시공의 효과를 수치해석을 통하여 분석하였다. 두 시공법들의 효과 분석을 위하여 3차원 에너지방정식과 비정상 비압축성 Navier-Stokes 방적식의 비정상 해를 구하였다. 수치해석에서 물의 자연대류와 소방 배관의 열전도 방정식이 상호작용을 하므로 복합열전달 해석을 상용코드 ANSYS-FLUENT에서 제공하는 압력-속도 연성기법들 중의 하나인 SIMPLE 알고리즘을 이용하여 수행하였다. 수치해석을 통하여 시간에 따른 배관 내의 유동장 및 온도분포와 배관 내 물의 최대 및 최소온도 변화를 고찰하였다. 수치해석 결과 배관 단위 길이 당 투입열량이 동일한 경우에 감기 시공과 직선 시공의 동파방지 효과는 거의 동일함을 확인하였다. 따라서, 열선 손상과 단락 등을 고려하면 직선 시공이 더 나은 시공법이라 판단된다.

• Journal of Biosystems Engineering
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• 제42권4호
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• pp.330-338
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• 2017

Purpose: The smartphone is actively being used in many research fields, primarily in medical and diagnostic applications. However, there are cases in which smartphone-based systems have been developed for agriculture, environment, and food applications. The purpose of this review is to summarize the research cases using smartphone cameras in agriculture, environment, and food. Methods: This review introduces seventeen research cases which used smartphone cameras in agriculture, food, water, and soil applications. These were classified as systems involving "smartphone-camera-alone" and "smartphone camera with optical accessories". Results: Detecting food-borne pathogens, analyzing the quality of foods, monitoring water quality and safety, gathering information regarding plant growth or damage, identifying weeds, and measuring soil loss after rain were presented for the smartphone-camera-alone system. Measuring food and water quality and safety, phenotyping seeds, and soil classifications were presented for the smartphone camera with optical accessories. Conclusions: Smartphone cameras were applied in various areas for several purposes. The use of smartphone cameras has advantages regarding high-resolution imaging, manual or auto exposure and focus control, ease of use, portability, image storage, and most importantly, programmability. The studies discussed were achieved by sensitivity improvements of CCDs (charge-coupled devices) and CMOS (complementary metal-oxide-semiconductor) on smartphone cameras and improved computing power of the smartphone, respectively. A smartphone camera-based system can be used with ease, low cost, in near-real-time, and on-site. This review article presents the applications and potential of the smartphone and the smartphone camera used for various purposes in agriculture, environment, and food.

• Applied Microscopy
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• 제42권2호
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• pp.111-114
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• 2012

The scanning electron microscopy is an ideal technique for examining plant surface at high resolution. Most hydrate samples, however, must be fix and dehydrate for observation in the scanning electron microscope. Because the microscopes operate under high vacuum, most specimens, especially biological samples, cannot withstand water removal by the vacuum system without morphological distortion. Cryo-techniques can observe in their original morphology and structure without various artifacts from conventional sample preparation. Rapid cooling is the method of choice for preparing plant samples for scanning electron microscopy in a defined physiological state. As one of cryo-technique, high-pressure freezing allows for fixation of native non-pretreated samples up to $200{\mu}M$ thick and 2 mm wide with minimal or no ice crystal damage for the freezing procedure. In this study, we could design to optimize structural preservation and imaging by comparing cryo-SEM and convention SEM preparation, and observe a fine, well preserved Arabidopsis stem's inner ultrastructure using HPF and cryo-SEM. These results would suggest a useful method of cryo-preparation and cryo-SEM for plant tissues, especially intratubule and vacuole rich structure.