Numerical Analysis of Radio‑Frequency Inductively Coupled Plasma Spheroidization of Titanium Metal Powder Under Single Particle and Dense Loading Conditions

Jun‑Seok Nam,Eonbyeong Park,Jun‑Ho Seo 대한금속·재료학회 2020 METALS AND MATERIALS International Vol.26 No.4

In order to allow more practical prediction of RF (radio-frequency)–ICP (inductively coupled plasma) spheroidizationresults of titanium metal powder, numerical analyses under single particle and dense loading conditions were carried outand the results were compared. First, both of the numerical results for Ar inductively coupled plasma with the power levelof 30 kW revealed that the injected particles can experience not only spheroidization by melting, but also size reduction byevaporation. In addition, this size reduction was found to strongly depend on the initial sizes of the injected particles, due tothe relatively short heating time. For example, the 100 μm Ti particles were computed to hardly experience size reduction byevaporation regardless of feeding rates. However, relatively small Ti particles < 100 μm can be rapidly heated up to boilingpoints during the short flight of plasma, resulting in the size reduction by the surface evaporation. In particular, numericalresults under dense loading condition showed that the final sizes of these small Ti particles can be changed depending onthe feeding rate. For example, a single 60 μm Ti particle was calculated to be a 51 μm spherical Ti particle due to the excessiveheating. However, with the increase of feeding rate up to 1.0 kg/h, the final sizes of the as-treated Ti powder couldbe improved to 55 μm due to the plasma temperatures decreasing through complicated plasma–particle interactions. Bypredicting the relationships between the feeding rates and the initial diameters of Ti powders at a given plasma power level,numerical modellings under single particle and dense loading conditions can help in optimizing the RF–ICP spheroidizationprocess of titanium metal powder.

당(唐) 태종대(太宗代) 반위(反胃) 치료법의 개발과 백제(百濟) 의자왕(義慈王)의 질병

박준형 ( Park Jun-hyoung ),서영교 ( Seo Young-kyo ) 대구사학회 2021 대구사학 Vol.142 No.-

唐은 기본적으로 隋의 의료체계를 수용하면서도 醫術世家의 秘傳에 의해 분산ㆍ난립된 醫術의 독점을 국가의 의료체계라는 公的 영역으로 흡수하고자 하였다. 나아가 당은 그 의술을 민간에 유포함으로써 점차 의술세가의 독점적 입지를 좁혀 나갔다. 공익을 위한 의술 공개는 당 왕조의 존재 이유를 백성들에게 가장 효율적으로 각인시키는 방법의 하나였고, 이는 초기 왕조의 안정화에 기여하였다. 당 태종대 당나귀오줌을 이용한 반위 치료법 개발은 이러한 의료정책의 결실이었다. 蔣ㆍ許ㆍ巢氏 醫官들의 연구를 통해 이루어낸 새로운 치료 법은 즉위 초반부터 숙환이 있던 의자왕에게도 주목받았다. 644년 초 의자왕은 당에 파견된 사신을 통해 의사를 알아보았고, 그해 말 입당한 태자 夫餘康信이 당 태종에게 蔣元昌의 왕진을 요청했다. 당시 장원창은 益州道로 파견나가 있었기 때문에 당 태종은 그를 백제에 보낼 수 없었다. 결과적으로 태자를 보내 백제의 신라공격에 대한 입장을 해명하고 신라를 침공하지 않겠다고 약속했던 의자왕이 645년에 신라를 공격했다. 그해 고구려와 전쟁을 시작한 당 태종은 신라를 이용하여 고구려의 병력을 남쪽으로 분산시키고자 했던 의도가 무산되었다. 현재 학계에서는 백제의 신라 공격 이유를 명확하게 설명하지 못하고 있다. 645년 백제의 신라 공격으로 백제와 당의 관계가 악화되었다. 이는 신라가 대당외교에서 성공할 수 있는 여건을 만들어 주었다. 이런 점에서 645년 백제의 신라 공격은 의자왕의 질병과 의사 장원창의 왕진 요청 거부가 중요하게 작용했던 결과라고 할 수 있다. Tang China(618-907), which inherited the medical system of the preceding Sui China(589-618), attempted to reorganize it by absorbing various medical traditions which were then monopolized by hereditary medical families. The hereditary remedies and knowledge of medical specialists who were employed as government physicians were integrated into the state medical system, and the newly developed remedies were open to public. The development of Banwi (反胃, gastric disorder) remedy using donkey urine was one of the cases demonstrating the success of the early Tang medical system. The remedy, developed through a joint research by the physicians from three prestigious medical families in early Tang, was soon to be known to Baekje. King Uija (r. 641-660) of Bakje, who had been suffered from Banwi, dispatched envoys to Tang to ask to send Jiang Yuan-chang to Baekje in 644. The Baekje court seems to have regarded Jiang, a physician who participated in the development of new Banwi remedy, as the most qualified person to cure King Uija. Tang government, however, could not dispatch Jiang to Baekje as he was then working near Sichuan province, hundreds miles from Chang'an, the capital of Tang. As a result, King Uija missed a chance of being treated with the new remedy. Then Baekje, which had once promised not to attack Shilla by sending a prince to Tang, resumed invasion of Shilla in 645, spoiling Emperor Taizong's (r. 626-649) plan to mobilize Baekje's army in his campaign against Goguryeo. As the aftermath of this incident, the relation between Baekje and Tang was irreversibly deteriorated, while Shilla succeeded to consolidate the Shilla-Tang alliance which led to the fall of Baekje in 660. From the perspective of medical diplomacy between Baekje and Tang during the mid 7th centuries, Tang’s failure to meet Baekje’s request for the medical support might have had a grave effect on the Baekje’s decision to move against the Tang’s interests. Park, Jun-hyoung (Naval Academy / shimani5075@hanmail.net) Seo, Young-kyo (Jungwon University / syk367@naver.com)

응급실에서 소아환자의 진정제로서 케타민(Ketamine)의 사용

서정필,박준석,황태식,장석준,김승호 대한응급의학회 2000 대한응급의학회지 Vol.11 No.3

Background: Ketamine use in emergency room has been increased. It has rapid onset of action and appropriate duration of action. It does not need endotracheal intubation and produces potent analgesia, sedation, and amnesia. The object of this study is to determine the safety and the degree of physician's satisfaction in relation to ketamine use. Materials and Methods: This is a prospective study using protocol. Pediatric trauma patients who need sedation were given IM ketamine(4 ㎎/㎏) and atropine(0.01 ㎎/㎏) in a same syringe. Monitoring of patients was done by EM residents and complications of ketamine use were recorded. Physician's satisfaction was also recorded after the procedure. Results: Intramuscular ketamine was administered 54 times, mainly for laceration repair. Physicians completed protocol for 51 of treated children. The median time for onset of sedation was 6.5±2.4 min, and duration of action was 32.4±10.8 min. Hypersalivation occurred in 9.8%(n=5); random movement 3.9%(n=2), emesis during procedure(n=1), emesis at home(n=1), and transient oxygen desaturation(n=1). All were quickly identified and treated without specific airway management and sequelae. Of 84% of physicians was satisfied with ketamine use for pediatric sedation. Conclusion: Intramuscular ketamine can be administered safely and satisfactorily in emergency room to facilitate pediatric procedures in conjunction with a defined protocol and appropriate monitoring.

1992학년도 신입생 실태조사 결과분석

전광희,편서영 충남대학교 1993 學生生活硏究 Vol.20 No.-

라즈베리파이를 이용한 스마트미러

최서희,전준수,송민규,이재건,이순흠 순천향대학교 부설 산업기술연구소 2021 순천향 산업기술연구소논문집 Vol.27 No.2

If we are looking for something that can be found anywhere in public places, homes, and and even toilets, we will be able to choose a mirror that can easily reflect us. To satisfy the convenience needs of people, we can automatically introduce various useful information on mirrors that are often used by anyone, or add functions such as measuring human body temperature in line with the recent trend of public health due to the COVID-19 pandemic. The system presented in this paper aims to improve the convenience of users who frequently look in the mirror by displaying visual information on a translucent mirror as well as being able to reflect the image as explained above.

탄소섬유 적층혼성부재의 계면수 변화에 따른 축 압궤 특성

서현경,박준우,양용준,황우채,양인영 朝鮮大學校 機械技術硏究所 2007 機械技術硏究 Vol.10 No.1

알루미늄과 CFRP는 대표적인 경량화 재료이다. 알루미늄 부재는 안정적인 소성 변형에 의해 에너지를 흡수하며, CFRP 부재는 비강성과 비강도가 우수하고 불안정한 취성파괴로 인해 에너지를 흡수한다. 이러한 각각 알루미늄과 CFRP 부재의 압궤 특성을 기초로 두 재 료의 결합에 의해 서로의 장점에 대한 시너지 효과를 얻기 위해 혼성구조부재를 제작하였다. 본 연구에서는 알루미늄 부재의 외측을 CFRP로 강화시킨 혼성구조부채를 제작하여 CFRP의 계면수 변화에 따른 축 방향 준정적 압궤실험을 행하여 사각 및 원형 단변 모형의 혼성구조부재의 압궤 특성을 조사하였다. 실험 결과 혼성구조부재는 내부의 알루미늄 부재의 연성 성질 때문에 CFRP 부재의 불안정한 취성 파괴를 보완하여 비교적 안정적인 압궤 모드를 보였다. 하지만 혼성구조부재는 계면수 변화에 대해 에너지 흡수성과 압궤 모드는 별다른 영향을 보이지 않았다. The aluminum or CFRP is representative of light-weight materials. The aluminum tubes absorb energy by stable plastic deformation and the CFRP tubes absorbs energy by unstable brittle failure with higher specific strength and stiffness. Based on the respective collapse characteristics of aluminum and CFRP tubes, the aluminum CFRP compound tubes were manufactured to get a synergy effect when the aluminum CFRP tubes were combined with the advantages of each tube. This paper is to investigate the collapse characteristics of square or circular shaped aluminum CFRP compound tubes subjected to quasi-static axial collapse tests which were conducted by changing the stacking conditions. Test results showed that the collapse of the aluminum CFRP compound tubes complemented unstable brittle failure of the CFRP tube due to the ductile characteristics of the inner aluminum tube. It turned out that interlaminar numbers of aluminum CFRP compound tubes have no influence on the energy absorption and collapse modes of the tubes.

월악산 잣나무 및 화백나무 형성층의 계절적 활동과 적산온도와의 관계

박준희, 강현정, 이해진, 서정욱 충북대학교 농업과학기술연구소 2022 農業科學硏究 Vol.38 No.2

The current study was conducted to investigate (1) the duration of cambial activity and (2) the effect of degree days on the initiation of cambial activity of the Pinus koraiensis (PK) and Chamaecy- paris picifera (CP) planted in Mt. Worak. In addition, the differences of the seasonal cambial activities according to the diameter were also investigated using C. picifera with a diameter of 30 cm (CPL) and 15 cm (CPS), which were planted in the same year. The cambium samples were weekly collected using a mini-borer (Ø 2 mm), so called Traphor, between April and October in 2017. The results obtained are as follow. The initiation of the cambial activity of CP (April 21-28) were slightly earlier than PK (April 21). The species with the longest cambial activity was CPS (147.2±12.1 days), followed by PK (141.6±9.8 days) and CPL (139±12.1 days). The degree days inducing the initiation of the cambial activ- ity for PK and CP were 180.5 and 180.5-242.8, respectively.

자동차차체 및 부품제조업 산업장의 작업환경실태에 관한 조사 연구

서준호,문덕환,김정호,이채관,황용식,손병철,김대환,이창희,김휘동,이채언 인제대학교 백병원 2002 仁濟醫學 Vol.23 No.5

Objectives: For the purpose of preparing the fundamental data and control the working environment and assessing the status of working environmental in manufacturing industry of bodies for motor car and of parts. Methods and Materials: Accessories for motor car and its engines the auther measured the noise level, concentration of dust, heavymetals, organic solvents, chemicals to 99 industries(24 working processes) form Feb. 2000 to Oec. 2000. Results: The results were as follows : 1. Mean noise level cutting, grinding, pressing, foundries and shot-blast was exceeded to threshold limit value(TLV) of noise. 2. Mean concentration of total dust was not exceeded to TLV. 3. Mean concentration of Mn in welding process and Pb in drying, welding, fabricating, rolling was exceeded to TLV. 4. Mean concentration for chemicals and organic solvents were not exceeded to TLV. 5. Mean concentration of dust and heavymetals were statistical significant difference between with local ventilation system and without local ventilation system. Conclusion: Above results, author suggest to prepare more passively control to working environment where exceeded the TLV.

국내은행들의 전산화전략에 관한 연구

서준석 경일대학교 산업정보연구소 2000 産經硏究 Vol.6 No.2

최근 들어 국내은행들은 전산기기의 설치 확대 및 전산인력의 확충, 전산예산의 확대 등을 통해 효율적인 전산시스템을 구축하고자 노력하고 있다. 이는 급변하는 금융환경하에서 전산시스템 구축을 토대로 한 다양한 서비스 제공이 은행수익과 직결된다는 인식확산에 따른 것이다. 이러한 상황인데도 불구하고 국내은행들의 전산화전략에 대한 연구는 거의 없다는 점이다. 이와 같은 상황하에서 본 연구의 목적은 첫째, 미국, 일본과 국내은행들의 전산화전략을 비교분석하여 앞으로의 연구에 필요한 이론적 근거와 통계적 가설검증의 기초를 마련하는 것이고 둘째, 앞장의 비교분석한 결과를 바탕으로 국내은행들의 효율적인 전산화전략을 제시하였다.

생체신호 처리용 ASIC 칩 개발

서희돈,이준하 경북대학교 센서기술연구소 1997 연차보고서 Vol.1997 No.-