• 한국안전학회지
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• 제21권4호
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• pp.60-65
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• 2006

It is a well known fact that LCD is a central part of the IT industry which is important in the present and the future. But the biggest problem of LCD manufacturing is maintaining a cleaning room environment and administration. Therefore the purpose of this study is to first, prevent the yield depreciation and damage of products, and second, protect the worker ftom accidental electrostatic discharge during LCD manufacture. The soft x-ray ionizer is a type of electrostatic reducer device. It protects against electrostatic discharge in the cleaning room environment and is a necessary environmental factor during LCD production. The positive aspects of the soft x-ray are its shorter time and wider angle of exposure. But the negative aspect of the soft x-ray is its need for several shielding of protection from the harmful x-ray exposure. On this study, the development of the Air Nozzle-type ionizer to amend and refine some problems. For example, examined the electrostatic reduce device of a soft x-ray type and discovered the ion did not go inside well. also workers to be free from danger. An Air Nozzle-type ionizer is comprised of soft x-ray radiation and ionized air production. Air is injected through the nozzle after being ionized from radiation. It supplies air keeping the same pressure into the end foundation of ion production. The soft x-ray is the structure which radiates ionized air through the nozzle (21 holes) having micro holes of the ionizable radiation after ionizing the inside air by the ion production. A worker does not need a cover to protect against x-rays and the Air Nozzle-type ionizer is easy to set up and is more effective at eliminating electrostatic.

• Archives of Plastic Surgery
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• 제44권1호
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• pp.42-47
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• 2017

Background Skin erosion is a dire complication of implantable cardiac pacemakers and defibrillators. Classical treatments involve removal of the entire generator and lead systems, however, these may result in fatal complications. In this study, we present our experience with a simplified salvage technique for exposed implantable cardiac electronic devices (ICEDs) without removing the implanted device, in an attempt to reduce the risks and complication rates associated with this condition. Methods The records of 10 patients who experienced direct ICED exposure between January 2012 and December 2015 were retrospectively reviewed. The following surgical procedure was performed in all patients: removal of skin erosion and capsule, creation of a new pocket at least 1.0-1.5 cm inferior to its original position, migration of the ICED to the new pocket, and insertion of closed-suction drainage. Patients with gross local sepsis or septicemia were excluded from this study. Results Seven patients had cardiac pacemakers and the other 3 had implantable cardiac defibrillators. The time from primary ICED placement to exposure ranged from 0.3 to 151 months (mean, 29 months. Postoperative follow-up in this series ranged from 8 to 31 months (mean follow-up, 22 months). Among the 10 patients, none presented with any signs of overt infection or cutaneous lesions, except 1 patient with hematoma on postoperative day 5. The hematoma was successfully treated by surgical removal and repositioning of the closed-suction drainage. Conclusions Based on our experience, salvage of exposed ICEDs is possible without removing the device in selected patients.

• Journal of Radiation Protection and Research
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• 제46권1호
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• pp.1-7
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• 2021

Background: The use of computed tomography (CT) device has increased in the past few decades in Japan. Dose optimization is strongly required in pediatric CT examinations, since there is concern that an unreasonably excessive medical radiation exposure might increase the risk of brain cancer and leukemia. To accelerate the process of dose optimization, continual assessment of the dose levels in actual hospitals and medical facilities is necessary. This study presents organ dose estimation using pediatric cerebral CT scans in the Kyushu region, Japan in 2012 and the web-based calculator, WAZA-ARI (https://waza-ari.nirs.qst.go.jp). Materials and Methods: We collected actual patient information and CT scan parameters from hospitals and medical facilities with more than 200 beds that perform pediatric CT in the Kyushu region, Japan through a questionnaire survey. To estimate the actual organ dose (brain dose, bone marrow dose, thyroid dose, lens dose), we divided the pediatric population into five age groups (0, 1, 5, 10, 15) based on body size, and inputted CT scan parameters into WAZA-ARI. Results and Discussion: Organ doses for each age group were obtained using WAZA-ARI. The brain dose, thyroid dose, and lens dose were the highest in the Age 0 group among the age groups, and the bone marrow and thyroid doses tended to decrease with increasing age groups. All organ doses showed differences among facilities, and this tendency was remarkable in the young group, especially in the Age 0 group. This study confirmed a difference of more than 10-fold in organ doses depending on the facility and CT scan parameters, even when the same CT device was used in the same age group. Conclusion: This study indicated that organ doses varied widely by age group, and also suggested that CT scan parameters are not optimized for children in some hospitals and medical facilities.

• Design & Manufacturing
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• 제15권4호
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• pp.65-71
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• 2021

In the early days of laser invention, it was simply used as a measuring tool, but as lasers became more common, they became an indispensable processing tool in the industry. Short-wavelength lasers are used to make patterns on wafers used in semiconductors depending on the wavelength, such as CO2 laser, YAG laser, green laser, and UV laser. At first, the hole of the PCB board mainly used for electronic parts was not thin and the hole size was large, so a mechanical drill was used. However, in order to realize product miniaturization and high integration, small hole processing lasers have become essential, and pattern exposure for small hole sizes has become essential. This paper intends to analyze the characteristics through patterns by exposing the PCB substrate through DMD and polygon scanner, which are different optical systems. Since the optical systems are different, the size of the patterns was made the same, and exposure was performed under the optimal conditions for each system. Pattern characteristics were analyzed through a 3D profiler. As a result of the analysis, there was no significant difference in line width between the two systems. However, it was confirmed that dmd had better pattern precision and polygon scanner had better productivity.

• 대한방사선기술학회지:방사선기술과학
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• 제30권2호
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• pp.153-159
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• 2007

PACS의 도입에 발맞추어 시작된 digital 의료영상은 현재 방사선 진단 및 치료 영역에서 일반화되었으며 특히 진단영역에서는 눈부신 발전을 거듭하고 있다. 치료영역에서의 digital image 구현은 상대적으로 느린 성장과정을 거쳐 오늘에 이르고 있다. 본 논문은 이러한 analog에서 digital로 변화하는 흐름을 인식하여 정도관리(Quality Assurance) 업무 중 mechanical check 부분을 digital image base 업무로 대체하여 수행하고, 기존의 육면체 또는 사각형틀의 개념을 탈피한 구형(球形)의 Spherical mechanical check device(SMCD) 고안하여 그 실용성을 실험하였다. Source(target)에서 image detecter 간의 거리가 항상 일정하고, Spherical mechanical check device(SMCD)의 중심까지 거리가 일정하다면 어느 방향에서 SMCD를 exposure하더라도 그 크기는 항상 일정하게 영상으로 표현 될 것이다. 이를 위해 정확한 반구(半球)를 2개 정밀 제작하여 그것을 합쳤을 때 정원(正圓)의 구(球)가 되도록 하였다. 이를 이용하여 radiation field와 light field의 일치도, radiation field 크기의 정확도($(5{\times}5,\;10{\times}10,\;15{\times}15\;cm)$), Collimator field 크기의 정확도($5{\times}5,\;10{\times}10,\;15{\times}15\;cm$), Gantry rotation isocenter check, Collimator rotation isocenter check, Room laser accuracy check, Collimator rotation angle check와 Couch rotation angle check 등 기존의 mechanical check를 digital image를 이용하여 실행할 수 있었으며, 기존의 Flat 또는 정육면체 형태의 mechanical check device로는 쉽게 하기 힘든 non-coplanar field에 적용되는 Gantry와 Couch가 동시에 rotation되었을 때 그 isocenter의 일치도를 real time으로 확인할 수 있었다.

• 한국방사선학회논문지
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• 제8권1호
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• pp.1-10
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• 2014

양방향 뇌혈관촬영기는 하나의 선원에서 방사선이 나오는 것이 아니라 정방향과 측방향에서 방사선 피폭이 이루어지기 때문에 방사선 관계종사자의 피폭이 더욱 많아질 수밖에 없다. 따라서 환자가 받는 선량도 중요하겠지만 시술을 시행하고 있는 방사선 관계종사자 역시 피폭선량을 줄일 수 있는 방법에 대해 많은 관심을 보이고 있다. 본 연구의 목적은 양방향 뇌혈관촬영기의 혈관검사 및 중재적방사선시술에 있어 X-선 관구에서 직접 조사되는 1차 방사선, 정방향관구와 측방향 검출기사이에서 발생하는 1차 산란방사선, 상대적으로 적지만 촬영실 벽이나 바닥에서 반사되는 2차 산란방사선 발생을 간과하지 않을 수 없기에 기존의 일반적인 차폐방법인 천정형 차폐, 테이블형 차폐방법에서 보다 더 적극적인 차폐방법인 측방향 차폐체의 방어용구를 설치하여 시술자가 받는 직접방사선 및 산란방사선에 의한 피폭선량을 최대한 줄이고자 노력하였다. 그 결과 투시측정에서는 생식샘 약 3.64배, 갑상샘 약 3.13배, 눈 약 4.42배 정도 더 감소하였고, 디지털 감산 혈관조영측정에서는 생식샘 약 4.98배, 갑상샘 약 3.00배, 눈 약1.67배의 피폭선량 감소효과를 얻어내었다. 결론적으로 양방향 뇌혈관촬영기의 혈관검사 및 중재적방사선시술시 설치하였던 측방향 차폐체의 방어용구는 일반적인 차폐방법보다 시술자의 피폭선량을 감소시키는데 많은 효과를 주었다고 사료된다.

• 정보보호학회논문지
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• 제26권5호
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• pp.1211-1221
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• 2016

사물 인터넷(Internet of Things) 환경에서의 장치들의 신뢰성 확보는 무엇보다 중요하다. 현재의 보안 위협은 대부분 정보의 노출과 조작, 또는 금전적인 이득을 위한 것이나, 사람의 삶이 사람을 둘러싼 장치들(Things)에 의해서 인터넷으로의 연결성의 강화되었을 때, 그 장치들로부터의 보안 위협은 직접적으로 사람을 겨냥할 가능성이 있다. 장치의 경우 인증은 인증 대상이 배타적으로 알고 있는 정보, 즉 비밀키를 검증함으로써 이루어진다. 하지만 공격자가 물리적으로 장치를 수정한다면 더 이상 비밀키를 알고 있다는 것은 신뢰의 증거가 될 수 없게 된다. 따라서 코드 검증(code attestation)과 같은 강력한 신뢰 확보 방법이 필요하다. 이 논문에서는 검증의 효율을 위해 비용이 적은 소프트웨어적인 코드 검증을 사용하였다. 원본 코드 복사를 통한 회피 방법에 대해 안전한 코드 검증 방법을 제시하고 이를 임베디드 디바이스에 적용하여 성능을 분석해 보인다.

• 근관절건강학회지
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• 제31권1호
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• pp.42-52
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• 2024

Purpose: This study aimed to identify the factors affecting compliance with personal protective equipment (PPE) use among medical device reprocessing staff. Methods: This descriptive cross-sectional study included 163 cleaning staff members from ten general hospitals in Seoul and Gyeonggi. Data were collected using self-report questionnaires administered between July and September 2023. Analysis included t-tests, ANOVA, Pearson's correlation coefficient, Bonferroni correction, and multiple regression, conducted using SAS ver.9.4. Results: Statistically significant differences in compliance with PPE were found based on department and exposure to contamination within six months (t=-2.82, p=.007). Attitudes toward PPE (r=.22, p=.006) and awareness of the safety climate (r=.22, p=.006) showed a statistically significant positive correlation with PPE compliance. Factors influencing use of personal protective equipment by cleaning staff during medical device reprocessing were department, compliance with PPE, and awareness of the safety climate. The explanatory power of these factors was 58.0%. Conclusion: Improving PPE compliance and creating a safe cleaning environment entails fostering a supportive safety climate. Additionally, regular training that takes into consideration the characteristics of the cleaning staff, alongside continuous monitoring, is required.

• 한국전기전자재료학회논문지
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• 제28권11호
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• pp.727-730
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• 2015

In this paper, we fabricated organic compounds detector using the MWCNT/PMMA (multi-walled carbon nanotube / polymethylmethacrylate) composite film. We used polymer film as a matrix material for the device framework, and introduced CNTs for reacting with the organic compounds resulting in changing electrical conductivity. Spray coating method was used to form the MWCNT/PMMA composite film detector, and pattern formation of the detector was done by shadow mask during the spray coating process. We investigated changes of electrical conductivity of the detector before and after the organic compounds exposure. Electrical conductivity of the detector tended to decrease after the exposure with various organic compounds such as acetone, tetrahydrofuran (THF), toluene, and dimethylformamide (DMF). Finally we conclude that organic compounds detection by the MWCNT/PMMA composite film detector was possible, and expect the feasibility of commercial MWCNT/PMMA composite film detector for various organic compounds.

• 전기학회논문지P
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• 제58권4호
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• pp.455-460
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• 2009

A number of factors combine to make ultraviolet radiation a superior means of water purification for ground water, rainwater harvesting systems and so on. Ultraviolet radiation is capable of destroying all types of bacteria. Additionally, ultraviolet radiation disinfects rapidly without the use of heat or chemical additives which may undesirably alter the composition of water. In a typical operation, water enters the inlet of a UV lamp and flows through the annular space between the quartz sleeve and the outside chamber wall. The irradiated water leaves through the outlet nozzle. Several design features are combined to determine the dosage delivered. The first is Wavelength output of the lamp, the Second is Length of the lamp - when the lamp is mounted parallel to the direction of water flow, the exposure time is proportional to the length of the lamp, the third is Design water flow rate - exposure time is inversely related to the linear flow rate, the forth is Diameter of the purification chamber - since the water itself absorbs UV energy, the delivered dosage diminishes logarithmically with the distance from the lamp. In this paper, It describe the how to design optimal UV disinfection device for ground water and rainwater. To search the optimal design method, it was performed computer simulation with 3D-CFD discrete ordinates model and manufactured prototype. Using proposed design method manufactured prototype applied to disinfection test and proved satisfied performance.