• 구강회복응용과학지
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• 제31권4호
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• pp.340-348
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• 2015

임플란트주위염(peri-implantitis)은 기능중인 골유착 임플란트 주위의 조직에서 생기는 사이트 별 감염성 질환이며 임플란트 후기 실패(late failure)의 원인으로 가장 높은 비율을 차지한다. 여러 연구들을 통해 미생물 침착이 임플란트주위염에 미치는 영향이 보고된 바 있으며 세균막의 제거는 임플란트주위염의 치료 시 필수조건이 된다. 최근에 여러 연구들을 통해 티타늄 임플란트에 레이저를 사용하여 표면을 살균, 정화 시키는 방법에 대한 실험이 많이 보고되고 있다. 본 논문에서는 임플란트주위염 처치에 있어 레이저가 갖는 효능에 대한 최근 연구 결과들을 문헌고찰을 통해 되짚어보고자 한다.

• 방사성폐기물학회지
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• 제16권1호
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• pp.93-105
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• 2018

향후 원자력시설 해체 시 막대한 양의 해체 콘크리트 폐기물이 발생할 수 있음을 감안하였을 때, 방사성 콘크리트 폐기물의 최적 처리기술에 대한 면밀한 검토와 향후 기술개발 방향에 대한 논의는 반드시 필요하다. 본 논문에서는 방사성 콘크리트 폐기물의 국내외 발생 사례를 종합해 보고, 처리 대상이 되는 방사성 콘크리트 폐기물의 특성을 검토하였다. 또한, 종래의 방사성 콘크리트 처리기술로써 기계적 제염기술, 화학적 제염기술, 부피감용기술, 재활용 및 고화기술에 대한 국내외 적용사례를 정리하고 기술 개발 동향을 살펴봄으로써 기존 기술의 한계점을 파악하고 기술 고도화 방향을 고찰해 보고자 한다.

• 대한치과의사협회지
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• 제53권12호
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• pp.906-909
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• 2015

Peri-implantitis is the inflammatory process, such as edema, bleeding, pus, of the mucosa surrounding dental implants. As the symptoms become severe, the surrounding bone is absorbed causing the implant surface to be exposed. Clinicians treat periimplantitis in various ways since a gold standard for the treatment of peri-implantitis has not been established. Various treatment methods include mechanical, chemical surface treatment and surgical excision, and recently decontamination of the implant surface using various types of lasers has been proposed. Thus, this study reviews the types of lasers and its effects that can be used for the treatment of peri-implantitis.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2003년도 ICCAS
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• pp.849-854
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• 2003

The Korea Atomic Energy Research Institute has developed a teleoperated cleaning robot for use in the radioactive zone of the isolation room of the Irradiated Material Examination Facility where direct human access to the interior is strictly limited. The teleoperated cleaning robot that was designed to completely eliminate human interaction with the hazardous radioactive contaminants has five remotely replaceable submodules - a mobile module for navigation, a cleaning module for dislodging and sucking contaminated waste, a sensing module for obstacle avoidance, a collection module for storing the acquired waste, and a cover module for protecting the collection module. This cleaning robot is capable of cleaning the contaminated floor surface of the isolation room and collecting loose dry spent nuclear fuel debris and other radioactive waste fixed or scattered on the floor surface. The developed cleaning robot is operated either by a manual control or by autonomous control in conjunction with a graphical simulator, by which the human operator can monitor and intervene the robot performing cleanup tasks in the isolation room. In this paper, we present the mechanical and environmental design considerations and development of the teleoperated cleaning robot for radioactive isolation room use. We also demonstrate its mock-up performance test results from the viewpoint of a remote cleanup operation and remote maintenance.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2003년도 봄 학술발표회 논문집
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• pp.597-604
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• 2003

In the soil washing process, the contaminants are usually removed by abrasion from soil particles using mechanical energy and water However, organic contaminants with low water solubility like polycyclic aromatic hydrocarbons (PAH) are remained on soil particles. Previous studies have shown that surfactant possessing amphipathic activity enhances the solubility of organic materials. For this reason solutions with surfactants have been used to improve removal of organic contaminants on soil washing process. But, in this manner, many problems were found like complete loss of surfactants and additional contamination by surfactant. The remediation method using microemulsion has been introduced to overcome these disadvantages. In this case, surfactants are recycled by phase separation of microemulsion after remediation. In microemulsion process, the surfactant will be recycled by phase separation of the microemulsion into a surfactant-rich aqueous phase and an oil phase after extraction. That is why remediation concept applying microemulsion as washing media has been Introduced. Suitable microemulsion have to be used in order to have the chance of refilling the soil after decontamination and to avoid any risk due to toxicity. The purpose of this research is to evaluate effect of microemulsion to remediation of contaminated soil. We performed test with various organic contaminants like Pyrene and BTEX, also compared efficiency of remediation in microemulsion process with soil washing

• 한국방사성폐기물학회:학술대회논문집
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• 한국방사성폐기물학회 2018년도 추계학술논문요약집
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• pp.379-379
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• 2018

MXenes are a new family of 2D transition metal carbide nanosheets analogous to graphene (Lv et al., 2017; Sun et al., 2018). Due to the easy availability, hydrophilic behavior, and tunable chemistry of MXenes, their use in applications for environmental pollution remediation such as heavy metal adsorption has recently been explored (Li et al., 2017). In this study, three-dimensional (3D) MXene ($Ti_3C_2T_x$) films with high adsorption capacity, good mechanical strength, and high selectivity for specific radionuclide from aquose solution were successfully fabricated by a polymeric precursor method using vacuum-assisted filtration. The highest removal efficiency on the films was 99.54%, 95.61%, and 82.79% for $Sr^{2+}$, $Co^{2+}$, and $Cs^+$, respectively, using a film dosage of 0.06 g/ L in the initial radionuclide solution (each radionuclide concentration = 1 mg/L and pH = 7.0). Especially, the adsorption process reached an equilibrium within 30 min. The expanded interlayer spacing of $Ti_3C_2T_x$ sheets in MXene films showed excellent radionuclide selectivity ($Cs^+$ and/or $Sr^{2+}/Co^{2+}$) (Simon, 2017). Besides, the MXene films was not only able to be easily retrieved from an aqueous solution by filtration after decontamination processes, but also to selectively separate desired target radionuclides in the solutions. Therefore, the newly developed MXene ($Ti_3C_2T_x$) films has a great potential for radionuclide removal from aqueous solution.

• 한국방사선학회논문지
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• 제11권1호
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• pp.1-8
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• 2017

원전 해체 이후 원전 부지의 제한적 또는 무제한적 이용에 대해서 미국 NRC는 NUREG-1757 문서를 통해 제한적 또는 무제한적 부지 이용에 관한 방사선학적 기준을 제시하였고 사업자가 제염 및 복원 후 이 선량 기준이 충족됨을 증명할 수 있어야만 부지가 제한적 또는 무제한적으로 해제될 수 있다고 하였다. 이와 관련하여 NRC는 운영허가종료계획서(LTP; License Termination Plan)에 방사선학적 부지 해제 기준 준수를 입증하기 위하여 부지 해제 기준, 부지 특성 평가, 최종 방사선 조사 계획에서 주요 방사선원항, 유도농도기준(DCGL) 등을 기재하도록 하고 있다. 이 논문은 국내 원전 해체에 있어서 참조사례가 될 수 있는 Rancho Seco 원전 해체 사례를 참고 및 절차를 분석함으로써 2017년 영구정지가 예정된 고리 1호기뿐만 아니라 향후 해체 원전 부지의 해제 기준 마련에 있어 사용될 수 있는 방법을 검토하였다.

• 대한임상독성학회지
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• 제3권2호
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• pp.86-92
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• 2005

Purpose: The main cause of death due to acute organophosphate (OP) poisoning is believed acute respiratory failure caused by cholinergic reactions. Recently, advances in respiratory and intensive care make it possible to maintain the respiratory function of patients with OP poisoning, but the mortality rates remain high. The present study clarified the hemodynamics of patients with acute lethal OP poisoning. The purpose of this study was to analyse the outcomes and predictors of mortality in patients with acute OP poisoning requiring intensive care. Methods: We reviewed medical and intensive care records of patients with acute OP poisoning admitted to emergency department and ICU between March 1998 and Aug 2005. We collected patient information regarding poisoning, clinical, and demographic features. Results: During the study period, 67 subjects treated with intensive care and ventilator management in addition to gastric decontamination standard therapy with atropine and 2-PAM. Of 67 patients, 13 died. Kaplan-Meier survival analysis demonstrated a steep decline in the cumulative survival to $86.6\%$ during the first week. Mean arterial pressure < 60 mmHg within the first 24 hours was recognized as a poor prognostic indicators among mechanical ventilated patients. Conclusion: Most OP poisoning-related deaths occurred within the first week of poisoning. Mean arterial pressure lower than 60 mmHg might be the best predictor of poor outcome. We speculated that the refractory hypotension is the leading cause of death in patients with lethal OP poisoning that receiving mechanical ventilation and maximal supportive care.

• Tuberculosis and Respiratory Diseases
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• 제69권2호
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• pp.75-80
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• 2010

The year of 2009~2010 brought a number of concepts and new ideas were evaluated with promising results. However, some studies that challenged many beliefs. In acute respiratory distress syndrome (ARDS), recent clinical studies took into consideration of pathophysiologic changes of respiratory system compliance. Meta-analysis of positive end-expiratory pressure trials showed survival benefit of high positive end-expiratory pressure in ARDS. Until now, prone positioning did not show survival benefit in patients with ARDS. Extracorporeal membrane oxygenation (ECMO) based management improved survival in patients with severe ARDS. ECMO can be a management option in severe ARDS. Sedation is a standard practice in critically ill patients needing mechanical ventilation. However, Danish group reported less sedation of critically ill patients receiving mechanical ventilation was associated with an increase in days without ventilation. Although this single center study has some limitations, the overall results are promising. Use of maximal sterile barrier precautions (mask, sterile gown, sterile gloves, and large sterile drapes) with chlorhexidine-impregnated dressing reduced central venous catheter related infection. Selective oropharyngeal decontamination (application of topical antibiotics in the oropharynx) reduced the mortality rate of an intensive care unit (ICU) population. Normoglycemia in Intensive Care Evaluation and Survival Using Glucose Algorithm Regulation (NICE-SUGAR) trial reported intensive glucose control increased mortality among adults in the ICU. Some of the results of above papers are promising. However, some ideas may need for more frequent individual assessment and increase the workload of ICU staffs. Before implementation of new practice in ICU, we should take into consideration of individual hospital situation including human and material resources.

• 한국마이크로전자및패키징학회:학술대회논문집
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• 한국마이크로전자및패키징학회 2004년도 ISMP Pb-free solders and the PCB technologies related to Pb-free solders
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• pp.233-241
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• 2004

A new alloy definition will be presented concerning increasing demands for the board level reliability of miniaturized interconnections. The damage mechanism for LFBGA components on different board finishes is not quite understood. Further demands from mobile phones are the drop test, characterizing interface performance of different package constructions in relation to decreased pad constructions and therefore interfaces. The paper discusses the characterization of interfaces based on SnPb, SnPbXYZ, SnAgCu and SnAgCuInNd ball materials and SnAgCuInNd as solder paste, the stability after accelerated tests and the description of modified interfaces strictly related to the assembly conditions, dissolution behavior of finishes on board side and the influence of intermetallic formation. The type of intermetallic as well as the quantity of intermetallics are observed, primaliry the hardness, E modules describing the ability of strain/stress compensation. First results of board level reliability are presented after TCT-40/+150. Improvement steps from the ball formulation will be discussed in conjunction to the implementation of lead free materials In order to optimize ball materials for area array devices accelareted aging conditions like TCTs were used to analyze the board level reliability of different ball materials for BGA, LFBGA, CSP, Flip Chip. The paper outlines lead-free ball analysis in comparison to conventional solder balls for BGA and chip size packages. The important points of interest are the description of processability related to existing ball attach procedures, requirements of interconnection properties and the knowledge gained the board level reliability. Both are the primary acceptance criteria for implementation. Knowledge about melting characteristic, surface tension depend on temperature and organic vehicles, wetting behavior, electrical conductivity, thermal conductivity, specific heat, mechanical strength, creep and relaxation properties, interactions to preferred finishes (minor impurities), intermetallic growth, content of IMC, brittleness depend on solved elements/IMC, fatigue resistance, damage mechanism, affinity against oxygen, reduction potential, decontamination efforts, endo-/exothermic reactions, diffusion properties related to finishes or bare materials, isothermal fatigue, thermo-cyclic fatigue, corrosion properties, lifetime prediction based on board level results, compatibility with rework/repair solders, rework temperatures of modified solders (Impurities, change in the melting point or range), compatibility to components and laminates.