• Proceedings of the Korea Information Processing Society Conference
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• 2023.11a
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• pp.986-987
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• 2023

본 논문은 신경근육질환 환자의 이동 문제를 해결하고, 기존 전동킥보드 시스템의 한계와 문제점도 해결하는 '신경근육질환 환자를 위한 전동킥보드 안전 환경 시스템'을 제안한다. 주요 특징은 다음과 같다. 첫째, 헬멧 착용 검사를 통과해야만전동킥보드를 이용할 수 있다. 휴대폰 전면 카메라를 통해 사용자의 모습을 촬영하면 딥러닝 모델을 통해 헬멧 착용 여부를 판단한다. 둘째, 주행 금지구역에서는 이용자 추적 모드를 활성화하여 OpenCV를 통해 이용자를 검출및 추적하고이에 따라 모터 PWM을 조절해서 방향 및 속력을 조절함으로써 이용자를 추적한다. 셋째, 헬멧 내 자이로 센서와 쇼크 센서를 통해 주행 사고를 감지하고 SMS를 이용해 해당 보호자에게 자동으로 사고 정보를 전달한다.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 1999.05a
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• pp.45-45
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• 1999

일반 구조용 탄소강은 수용액 중에 노출될 때 부식에 의한 손상을 받기 쉽다. 부식의 양지를 위한 방법으로 사용 매체 중에 부식억제제를 첨가하여 탄소강의 부식속도를 낮추는 방법은 흔히 사용되는 방법이다. 부식억제제는 부식억제의 원리에 따라 양극부식억제제, 음극부식억제제 그리 고 이들의 혼합부삭억 세제 둥 여러 종류가 목적에 따라 사용되고 있다. 일반적으로 부식억제제의 성능 평가에는 무게감량볍, 표면분석법, 분극거동측정, 부석전위, 선 형분극법에 의한 부식속도 측정 등 다양한 방법이 시도되고 있다. 이 중에서 전기화학적 평가볍 은 부삭억제제의 작용 기구 규명 등을 위하여 많이 사용되고 있다. 한편 제품의 개발 단계에서 실질적인 평가법으로 갈리 사용하고 있는 방법은 무게 감량법인데 이 방법은 전면부식에 의한 금 속 손실량을 측정하여 부식억제능을 측정하는 방법이다. 그러냐 실제로 부삭억제제가 사용되고 있는 환경에서의 부식양상을 판찰하여보면 전면부식에 의한 손상보다는 국부부식에 의한 손상이 보다 치명적언 경우를 종종 목격할 수 있다. 이러한 관점에서 가존의 무게감량법은 한계가 있다. 따라서 본 연구에서는 이러한 국부부식을 보다 효과적으로 평가하기 위해 새로운 시험법을 도 입 상용 부식억제제의 종류별로 비교하였다. 부식억제제로는 수용액 중의 부식억제제로 널리 사용되고 있는 Nalco 39L과 본 연구실에서 SK해미칼과 공동 개발한 GH-110 등에 대하여 MCA(Multiple Crevice Assembly)를 이용 틈부식 저항성을 평가하였다. 또한 박막화된 전기저항형 부석속도 측정 센서를 틈부식 형태의 부식측정 에 적용하는 연구를 행하였다. 시험에 사용한 재갚는 천연가스의 감압 온도보상용으로 운전하는 가스히터의 주 구성 재료인 저탄소강을 사용하였으며 열화된 부식억제제 용액으로 사용기간이 서로 다른 수용액들에 대하여 평가 방법을 적용하여 비교하였다 다양한 부식억 제 제 수용액을 비교한 결과 MCA(Multiple Crevice Assembly)를 이용한 틈부식 억제능 시험은 실제 현장 사험 결과와 어느 정도 일치하는 결과를 보였다. 새로운 틈부식 저항성 측정법으로 시도한 철박막을 이용 틈부식 측정법은 육안 검사를 실시하지 않고도 틈부식의 전행 여부를 확인할 수 있는 가능성을 확인하였다.

• The Korean Journal of Nuclear Medicine
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• v.30 no.1
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• pp.118-125
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• 1996

Scrub typhus의 발현증상에는 저알부민혈증, 단백뇨, 전신 부종 등을 들 수 있다. 그러나, 저알부민혈증에 비해 단백뇨와 부종 등은 심하지 않은 경우가 많다. 본 연구에서는 저알부민혈증이 장내에서의 단백질 소실에 의한 것인지를 확인하고자 하였다. Scrub typhus가 의심되는 25명의 환자를 대상으로 (1) 저알부민혈증의 원인 장내 단백질 소실에 의한 것인지 여부와 (2) $^{99m}Tc$-HSA 신티그램의 진단적 유용성을 알아보고자 하였다. 신티그램은 혈청학적 검사상 Scrub typhus로 확인된 18명의 환자에서 (13예는 항생제 치료 개시후 1일에서 8일 사이에, 5예는 치료 전에 시행하였으며, 11예에서는 대변에서 alpha-1- antitrypsin (${\alpha}AT$)배설 여부를 확인하였다. 촬영방법은 $^{99m}Tc$-HSA 30mCi를 정맥 주사한 후, 2, 4, 6, 24시간에 복부 전면상을 얻었다. 판정은 소장과 대장의 주행 위치에서의 혈관외 방사능 소견을 장내 단백질 소실로 간주하였다. 13예에서 양성으로 판정하였는데, 이중 8예는 대변에서의 ${\alpha}AT$치도 높게 나왔다. 신티그램상 음성을 보인 5예중 2예에서는 대변중 ${\alpha}AT$치가 매우 높게 나왔는데 그 이유는 신티그램 검사는 치료 도중에 하였고, 대변 검사는 치료 전에 하였기 때문인 것으로 간주하였다. 결론적으로 전체 18예중 15예에서 신티그램이나 대변검사로 Scrub typhus로 진단하였다. 한편, 13예 (72%)에서 저알부민혈증을 보였는데 이중 4예는 장내단백질 소실과 단백뇨를, 5예는 장내단백질 소실만을, 3예에서는 단백뇨만을 보였고, 1예는 아무 소견이 없었다. 요약하면, 장내단백질 소실 소견은 Scrub typhus환자의 83%에서 보여, 혈중 알부민치가 저하되는 원인으로 추정된다. 따라서 $^{99m}Tc$-HSA 신티그램은 장내단백질 소실의 진단에 매우 유용한 검사방법이다. 또한, 검사방법이 다소 어렵지만 대변에서의 ${\alpha}AT$측정도 동위원소 검사상 음성 소견을 보이는 환자에게는 어느 정도 진단에 도움을 주리라 보여진다.

• Journal of the Korean Society of Radiology
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• v.15 no.7
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• pp.1041-1047
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• 2021

In this study, the effective dose for frequently general radiography among the diagnostic reference level (DRL) for examinations provided by the government in Korea was evaluated using the Monte Carlo N-Particle eXtended (MCNPX) simulation tool. We were selected to evaluate for a total of 5 examination sites which included head anterior-posterior, chest (posterior-anterior, lateral), abdomen anterior-posterior and pelvis anterior-posterior. Physical conditions such as tube voltage and tube current used in MCNPX simulation were used in domestic conditions of the Korea Disease Control and Prevention Agency (KDCA). To evaluate domestic medical radiation exposure, we used the HDRK-Man computerized human phantom manufactured based on the international standard ICRP 103 that was applied to the MCNPX simulation. The phantom could represent the standard body shape of Koreans. As a results, the effective dose corresponding to the DRL based on adult males of head anterior-posterior position was 0.086 mSv, chest posterior-anterior position was 0.05 mSv, chest lateral was 0.354 mSv, abdomen anterior-posterior position was 0.548 mSv, and pelvis anterior-posterior position was 0.451 mSv.

• Composites Research
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• v.33 no.3
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• pp.147-152
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• 2020

In this study, void behavior of composite laminate by local internal pressure gradient due to structural geometry and surface film application condition was experimentally evaluated through fabrication of spar/skin integrated structure specimens. Viscosity comparison and thermal analysis for both carbon fiber prepreg and surface film were conducted and cure characteristic and rate difference were analyzed. 2 types of spar/skin integrated structural specimens were prepared based on different application condition of surface film. Subsequently, those specimens were evaluated through visual surface inspection, non-destructive and destructive inspection. In a specimen #1 with full application of surface film, low pressurized area of composite laminate created by pressure gradient of structural geometry had voids. It exhibited that voids could not be evacuated and were locked in cured laminate by the influence of pre-cured surface film with relatively faster cure rate. In a specimen #2 without surface film, it revealed that all internal voids disappeared in the cured laminate. Therefore, it is verified that surface film acts as barrier film preventing void movement and evacuation during autoclave cure.

• The Korean Journal of Nuclear Medicine Technology
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• v.19 no.2
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• pp.74-80
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• 2015

Purpose Breast lymphoscintigraphy is an important technique to present for body surface precisely, which shows a lymph node metastasis of malignant tumors at an early stage and is performed before and after surgery in patients with breast cancer. In this study, we evaluated several methods of body outline imaging to present exact location of lesions, as well as compared respective exposure doses. Materials and Methods RANDO phantom and SYMBIA T-16 were used for obtaining imaging. A lesion and an injection site were created by inserting a point source of 0.11 MBq on the axillary sentinel lymph node and 37 MBq on the right breast, respectively. The first method for acquiring the image was used by drawing the body surface of phantom for 30 sec using $Na^{99m}TcO_4$ as a point source. The second, the image was acquired with $^{57}Co$ flood source for 30 seconds on the rear side and the left side of the phantom, the image as the third method was obtained using a syringe filled with 37 MBq of $Na^{99m}TcO_4$ in 10 ml of saline, and as the fourth, we used a photon energy and scatter energy of $^{99m}Tc$ emitting from phantom without any addition radiation exposure. Finally, the image was fused the scout image and the basal image of SPECT/CT using MATLAB$^{(R)}$ program. Anterior and lateral images were acquired for 3 min, and radiation exposure was measured by the personal exposure dosimeter. We conducted preference of 10 images from nuclear medicine doctors by the survey. Results TBR values of anterior and right image in the first to fifth method were 334.9 and 117.2 ($1^{st}$), 266.1 and 124.4 ($2^{nd}$), 117.4 and 99.6 ($3^{rd}$), 3.2 and 7.6 ($4^{th}$), and 565.6 and 141.8 ($5^{th}$). And also exposure doses of these method were 2, 2, 2, 0, and $30{\mu}Sv$, respectively. Among five methods, the fifth method showed the highest TBR value as well as exposure dose, where as the fourth method showed the lowest TBR value and exposure dose. As a result, the last method ($5^{th}$) is the best method and the fourth method is the worst method in this study. Conclusion Scout method of SPECT/CT can be useful that provides the best values of TBR and the best score of survey result. Even though personal exposure dose when patients take scout of SPECT/CT was higher than another scan, it was slight level comparison to 1 mSv as the dose limit to non-radiation workers. If the scout is possible to less than 80 kV, exposure dose can be reduced, and also useful lesion localization provided.

• Journal of the Korean Society of Radiology
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• v.11 no.4
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• pp.273-278
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• 2017

Among 45 patients of herniation of intervertebral disc with $L_4$ to $L_5$ herniation, who underwent infrared thermography, the number of female was larger than male and the age of 50s was highest. From the results measured from the distribution table, we have confirmed that there was no significant difference depending on sex and age (p> 0.05). The region of the highest ROI temperature for patients with $L_4-L_5$ intervertebral disc prolapse was the back of the posterior right tibia, and followed by the back of the left shin bone-below the front right knee-below the front left knee. There was a significant difference depending on the measured site. The average ROI temperature for patients was $30.30{\pm}0.50$ whereas that for normal persons was $31.20{\pm}0.58$, yielding the temperature difference of $0.66{\pm}0.59$ between the two groups. The ROI of patients was lower than $31.20{\pm}0.58$ (p <0.05) because the significance of the sample, which has been obtained from the results of a sample t-test, was less than 0.05 (p <0.05). From further researches, it may necessary to develope the methodology for correcting data regarding thermal environment and, in addition, to develope a new thermal index based on it. Therefore, we can confirm that pre-treatment for infrared thermography is very important in order to minimize the procedure for correcting data. It is required that radiologists who inspect disc herniations should carefully observe and consider the patients during their measurements.

• Journal of radiological science and technology
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• v.39 no.2
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• pp.199-208
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• 2016

$^{99}mTc-MAG_3$ Renal scan is a method that acquires dynamic renal scan image by using $^{99}mTc-MAG_3$ and dynamically visualizes process of radioactive agent being absorbed to kidney and excreted continuously. Once the test starts, ratio in both kidneys in 1~2.5 minutes was measured to obtain split renal function and split renal function can be expressed in ratio based on overall renal function. This study is based on compares split renal function obtained from data acquired from posterior detector, which is a conventional renal function test method, with split renal function acquired from the geometric mean of values obtained from anterior and posterior detectors, and studies utility of attenuation compensation depending on difference in geometric mean kidney depth. From July, 2015 to February 2016, 33 patients who undertook $^{99}mTc-MAG_3$ Renal scan(13 male, 20 female, average age of 44.66 with range of 5~70, average height of 160.40cm, average weight of 55.40kg) were selected as subjects. Depth of kidney was shown to be 65.82 mm at average for left and 71.62 mm at average for right. In supine position, 30 out of 33 patients showed higher ratio of deep-situated kidney and lower ratio of shallow-situated kidney. Such result is deemed to be due to correction by attenuation between deep-situated kidney and detector and in case where there is difference between the depth of both kidneys such as, lesions in or around kidney, spine malformation, and ectopic kidney, ratio of deep-situated kidney must be compensated for more accurate calculation of split renal function, when compared to the conventional test method (posterior detector counting).

• Journal of Naturopathy
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• v.9 no.1
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• pp.22-26
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• 2020

Purposes: The purposes of this study were to investigate the relationship between the standing position of the subject and the normal standing position(NSP) and the straight standing position(SSP) and to investigate the possibility of different body shape test results depending on the status of the image inspection apparatus. Methods: The images of the NSP and SSP were compared with each other by body line BLS system. Results: At the time of examination, the position of the camera was captured at a position 2.3 m vertically from the posterior position 45 cm behind the subject. This is a privacy protection method for covering the breast of the subject. Results: The physiological characteristics of the anatomical position of the body align image test are the living body. NSP and SSP tests showed different shapes of the pelvis AS(antero-supero) and pelvis rotation in the transverse plane. Shoulder and arm displacement was observed in the trunk extension image capture. Conclusions: In the body alignment test, the pelvis position test images of NSP and SSP are evaluated differently for pelvis rotation, AS, and PS. At the extension position of the trunk, a test of the maximal extension range showed that the left and right shortening of the shoulder anterior muscles could be observed. Inducing and testing the trunk extension is also useful.

• Journal of the Korean Society of Radiology
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• v.16 no.6
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• pp.741-749
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• 2022

Radiography-Testing that verify the quality of welding structures without destruction are overwhelmingly used in industries, but many safety precautions are required as radiation is used. The workers for Radiography-Testing perform the inspection by moving the Iridium-192 radiation source embedded in the transport container of the gamma-ray irradiator within or outside the facility. The general facility is completely blocked about radiation from the outside with thick concrete, but if it is difficult for worker to handle object of inspection, facilities ceiling can be opened. A general facility may be constructed using a theoretical dose evaluation method because all exterior facilities are blocked, but if the ceiling is open, it is not appropriate to evaluate radiation safety with a simple theoretical calculation method due to the skyshine effect. Therefore, in this study, the radiation safety of the facility was evaluated in the actual field through an ion chamber survey-meter and an accumulated dose-meter called as OSLD, and the actual evaluation environment was modeled and evaluated using the Monte Carlo simulation code as FLUKA. According to the direction of the irradiation, the radiation dose at the facility boundary was difficult to meet the standards set by the regulatory authority, and radiation safety could be secured through additional methods. In addition, it was confirmed that the simulation results using the Iridium-192 source were valid evaluation with the actual measured results.