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.

공조시스템을 적용한 석실 고분내 온ㆍ습도 분포

전용두,이금배,박진양,고석보,전희호 公州大學校 工學硏究院 生産技術硏究所 2005 論文集 Vol.13 No.-

Although the importance of good conservation of historic sites including ancient royal tombs is well aware, still not much attention has been paid for the facilities and systems to preserve those historic sites, which includes precious artifacts as wall paints and carved works, etc. Even the general understanding about the environment of the underground space of tombs is not satisfactory. In Korea, researchers have recently begun addressing the above issue and are making efforts to develop suitable HVAC(heating, ventilating and air-conditioning) systems for conservation of tombs. An experimental investigation was carried out to study the behavior of the HVAC system installed for a tomb. This tomb resembles in size and shape the original stone built tomb of Baek-je Dynasty, which dates back to 6th Century in southwest part of Korean peninsula. In this study, an HVAC system for a tomb(D×W×H=1.3m×3.0m×1.2m) was installed to maintain sui표 indoor conditions for conservation of tomb. The temperature and humidity inside the tomb were measured different of the setting. Finally, performance of the HVAC system is presented and discussed.

육우 비선호 부위를 활용한 육우햄의 품질특성

이주호, 최정석, 정준영, 최양일 忠北大學校 農業科學硏究所 2012 農業科學硏究 Vol.28 No.3

This study was undertaken to compare the quality characteristics of dairy beef ham. Dairy beef hams were manufactured using non-preferred portion (top round). 5 treatments were prepared: T1(beef 50% + pork emulsion 50%), T2(beef 65%emulsion 35%), T3(beef 80%emulsion 20%), T4(beef 90%emulsion 10%), T5(beef 100%emulsion 0%). In chemical composition, dairy beef content increases, moisture content was increased, fat content was decreased. In the meat quality characteristics, T5 showed higher (p<0.05) water holding capacity value than the others. Dairy beef content increases, product loss and cooking loss were decreased. In hunter color, dairy beef content increases, redness was increased. In texture profile analysis, T4 and T5 were significantly higher than the others. As a result, dairy beef ham with 80~90% dairy beef and 10~20% pork emulsion has low fat content, high product yield and superior texture profile, which could be developed as a dairy beef hams using non-preferred portion.

배가스 폐열회수를 위한 히트파이프 적용성 검토

전용두,박기호,고석보 公州大學校 工學硏究院 生産技術硏究所 2005 論文集 Vol.13 No.-

A Series of experiments are performed to investigate the heat transfer characteristics of sintered metal wick heat pipe especially focusing on the operational limit of maximum allowable thermal loads and the effect of inclination slope. Tested heat pipes are composed of copper tube with pure water as a working fluid. The outer diameter of the heat pipe is 6mm and the total length is 300mm, which covers the evaporator section(50mm), adiabatic section(100mm) and condenser section(150mm). respectively. Experimental data of wall temperature distribution along the axial locations are obtained to evaluate the performance of the heat pipe at different slopes. Each test is performed by changing the input thermal loads ranging from 5W to 30W.

독성물질의 세포사 기전 및 세포사 유발물질의 검색법 개발에 관한 연구(Ⅰ) : 독성물질로 인한 파킨슨병 모델에서의 세포사 기전 연구 Study on the cell-death mechanisms of toxin-induced parkinsonism

강태석,김종민,서경원,김영옥,김준규,오재호,이윤동,김규봉,오정자,송연정,임종준,전범석,문전옥,최광식 식품의약품안전청 2000 식품의약품안전청 연보 Vol.4 No.-

MPTP 독성물질이 도파민성 신경세포에 선택적으로 작용하여 산화성 손상에 의한 신경세포사를 일으키는 것을 이용하여 파킨슨병의 동물모델을 만들고, 이를 통해서 아폼토시스를 비롯한 포사의 기전에 대한 연구 및 너코틴의 신경세포 보호효과 여부를 판정하는 실험을 병행하고자 하였다. 파킨슨꾐의 동물모델을 MPTf 독성 물질을 이용하여 확립하였으며, MPTP(30mgag, i.p.)를 투여한 후 1, 2,3, 4, 5일째 흑질 조직을 채춰하여 tarm로 박걸하여 tyrosine hydroxylase 면역조직화학염색을 수행하여 cell countif우한 결과, control은 57.635ce11s, 1일째 친.OfDells,2일째 57.9±6cells,3일릴 없.3±죠ells, 4일째 49.0츠3cells, 5일째 39.4±Scells료 4, 3일째 뚜렷한 신경세포 수의 감소를 보였다. 신경세포사 기전 규명을 위한 아폼토시스 분걱에서는 벼PTP 투여 후 1, 2, 3, 4, 5일째 조직을 채취하여 Hoechst staining, TUNEL staining을 수곡하였는데 양성 반응을 보인 신경세포는 관찰되지 않아. 아폼토시스로 인한 세포사가 관찰되지 않았다. bIPTP 파킨슨병 동물모델에서 nicotine 보호효과 탐색에 관한 실험은 nicat푸e 0.2mgAg을 5일 퐁안 투여 후 리『fP(30mgag)를 CS7Bt/6 마은스에 복강 내주사로 nicotine과 병용 투여한 후 1, 2, 3, 4, 5일째 뇌를 적출하땄다. 신경세포사가 뚜렷이 관찰되기 시작하는 4, 5일째의 신경세포 수의 감소 정도를 20. 30% 정도 약화시키는 경향을 보였으나, nicotine 보호효과에 대한 추가 실헝이 현재 수행 중에 있다. The cause of Parkinson's disease (PD) is largely unknown. However, free radical toxicit? may plaf a role ip. the degeneration of substantia nigra, which is the Hajorfocus of pathological damages in PD. Recently, a neuroprotective effect of nicotine in PD has been suggested. Therefore, the mechanism of neurodegenerafion and protective potential o( nicotine in PD were investigated in the experimental modeB of Pll using a neurotoxin, C57BL/6mice were administered with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP, 30 mg/kg,j.p.). The degree of neurodegenerafion was determined by immunohistochemical stainiHB oftyrosine hydroxylase (TH). TH-positive cells on nigral sections were found 56.0 ±4, 57.9 ±6,52.315ce11s, 49.0±3cells, and 39,4±Scells at days 1, 2, 3, 4, 5, respectively (controls : 57.6±Scells). Hoechst and TUNEL staining showed no evidence of apoptosis. The exandnation on themice co-adrunistered with nicotine(0.2mgAg) and MPTP(30mgag) revealed a tendency ofnicotine protective effects. At days 4 and 5, the degree of TH-positive cells was decreased by20-30%, In corclusiffn, the role of apoptosis was not evidenced in this MPTP modeB of PB.The possible proteccon by nicotine should be elucidated with further studies.

마이크로스트립 지연선 여파기에 관한 연구

윤준식,박규호,윤철상,박준석,안달 호서대학교 반도체제조장비국산화연구센터 2000 학술대회 자료집 Vol.2000 No.1

일반적으로 LPA에서는 위상을 조정하기 위해 매우 긴 지연선을 필요로 한다. 지연성능은 고전력이나 저전력 모두에서 임의의 길이의 동축선로를 여러번의 과정을 거쳐 적용해봄으로써 구현된다. 그러나 동축선로형 지연선은 부피나 높은 삽입손실등의 제약이 많이 따른다. 본 논문에서는 마이크로스트립 형태의 지연선 대역통과 여파기를 설계하였고, 실험결과는 지연선여파기가 동축선로를 대신하여 LPA 시스템에 적용이 가능함을 보였다.

양측 쇄골하동맥 및 양측 신동맥 협착을 동반한 Takayasu 동맥염 1예

임선호,임수빈,오석규,이재홍,정진원,박양규,박옥규,소병준,노병석 대한순환기학회 1997 Korean Circulation Journal Vol.27 No.8

최근 6년간 연세의료원에서 경험한 한국인 안면골 골절에 대한 임상적 연구

권준호,이충국,이의웅,민우석,윤중호,박형식 大韓顎顔面成形外科學會 1989 Maxillofacial Plastic Reconstructive Surgery Vol.11 No.1

This is a series of continuing research on facial bone fractures of Koreans worked by Dept. of Oral and Maxillofacial surgery, Dental College of Yonsei University, Seoul, Korea, since 1972. The study was based on a series of 630 patients with facial bone fractures treated as in patient at Yonsei Medical Center, Yonsei University, during the period of Jan. 1982 through Dec, 1987. The results obtained are as follows: 1. The ratio of Men to Women was 4.3 : 1, and admissions for facial bone fractures have been increased year after 1984. 2. The age frequency was highest in the third decade(38.3%). and fourth, second, fifth decade in orders. 3. The traffic accident was the most frequent cause of facial bone fractures(51.3%). 4. The most common location of facial bone fractures was the Mandible(35.3%), and Zygoma complex(29.8%), Nasal bone(15.0%), Maxilla(11.0%) were next in order of frequency. 5. In 291 patients of Mandible fractures, 226(77.7%) had fractures only in Mandible and 65(22.3%) had another facial bone fractures. The most frequent fracture site of mandible was the Symphysis(43.0%) and Angle(22.4%), and Simple fracture was the most frequent in type of fracture(66.9%). Intermaxillarty fixatin & Open reduction was major method of treatment(36.9%). 6. In 394 patients of Midface fractures 323(82.0%) had fractures only in Midface and 71(18.0%) had another facial bone fractures. The most frequent site of Midface fractures was zygoma complex & zygomatic arch(42.7%), and Simple fracture was the most common type of fractures. Observation(Maxilla :44.2%, Zygoma :51.0%) and Open Reduction(Maxilla :20.0%. Zygoma :23.5%) were the major method of treatment. 7. The frequency of Nasal bone fracture was about 1/5 of Midface fractures, and Closed Reduction(42.2%) was the major method of treatment. 8. The complication was reported in only 16 patients, and Malunion was the major complication. 9. Head(44.4%), Lower extrimities(14.5%) and Eye(12.3%) were injured commonly with facial bone fractures. 10. The elapsed time from injury to hospital was within 24 hours in 73.8% of patients, however 15.5% of patients arrived the hospital 72 hours after injury.

불안 증상을 동반한 신체화 환자의 인지적 특성

나영석,정한용,권영준,이소영,박준호 大韓神經精神醫學會 2004 신경정신의학 Vol.43 No.6

Objectives : Assuming that somatization closely interacts with anxiety symptoms, one might speculate that anxiety symptoms will produce the significant differences in development, course and treatment of somatization and the cause of these differences will be elucidated in the cognitive aspect. This study was performed to examine the cognitive characteristics in terms of the somatosensory amplification and the symptom interaction in patients with somatization accompanied by anxiety symptoms. Methods : The following measures were administered to subjects who had a T-score of >60 on somatization subscale of Symptom Checklist-90-Revision (SCL-90-R) : 1) Minnessota Multiphasic Personality Inventory-Korean Version (MMPI-K), 2) Somato-sensory Amplification Scale (SSAS), 3) Symptom Interpretation Questionnaire (SIQ). There was a comparison of differences in the somatosensory amplification and the symptom interpretation between the anxiety group and the non-anxiety group divided by T-score of >60 on the psychasthenia subscale of MMSE-K. Multiple regression analysis was performed to determine the effect of the differences in the somatosensory amplification and the symptom interpretation on age, sex, marital status and level of education between those two groups. Results : There was a greater amplification of sensation in the anxiety group than the non-anxiety group. The former showed a higher level of physical, psychological and catastrophic interpretation than non-anxiety group except with regard to environ-mental interpretation. Somatization was affected by somatosensory amplification and physical interpretation in both groups, as well as psychological interpretation in the anxiety group. Conelusion : Regarding the cognitive aspect, the somatosensory amplification and symptom interpretation were more severely distorted in patients accompanied by anxiety symptoms. These results suggest that a therapeutic approach based on the cognitive charactehstics is essential for the effective management of somatizer.

간경변 환자에서 콜히친 사용에 의한 호중구성 백혈구감소증 1예

이호찬,이헌주,김용길,박재현,김성준,박준석 영남대학교 의과대학 2009 Journal of Yeungnam Medical Science Vol.26 No.2

Colchicine is an alkaloid that has been used for treating acute gouty arthritis, psoriasis, scleroderma and Behcet's syndrome. Colchicine decreased liver fibrosis in rats with carbon tetrachloride induced cirrhosis and in patients with many liver diseases. Therapeutic oral doses of colchicine may cause nausea, vomiting, abdominal pain and diarrhea. The adverse effect of colchicine associated with the dose is bone marrow suppression, and especially neutopenia. Neutropenia has often been reported in patients have taken an overdose of colchicine. We describe a 64-year-old female liver cirrhosis patient with neutropenia that was induced by a therapeutic dose of colchicine.