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.

품종별 감꽃 동결건조 분말의 유효성분 분석

김준한 ( Jun Han Kim ),박석희 ( Seok Hee Park ),문혜경 ( Hye Gyeong Mun ),이인선 ( In Seon Lee ),김종국 ( Jong Kuk Kim ) 한국식품저장유통학회 ( 구 한국농산물저장유통학회 ) 2006 한국식품저장유통학회지 Vol.13 No.6

감 품종별(도근조생, 고종시, 갑주백목, 차랑, 월하시, 상주둥시)로 감꽃을 개화기에 채취하여 동결건조 분말화한 감꽃분말에 함유된 유효성분을 분석, 비교하였다. 조지방 함량은 도근조생이 57.26%로 가장 높은 값을 보였으며, 유리당 조성은 fructose가 95~310 mg%, glucose는 75~281 mg%, sucrose가 7~28 mg%의 함유량을 나타내었고, 유기산 중 malic acid가 갑주백목(6월4일)에 225 mg%로 가장 많았고, tartaric acid도 189 mg%로 가장 많았다. 유리아미노산 중 hydroxy-L-proline은 월하시에 25.33 mg%, L-citrulline은 상주둥시(5월28일)가 58.83 mg%, L-threonine은 상주둥시(5월28일)가 11.88 mg%로 가장 많았다. 페놀산으로 caffeic acid는 갑주백목(6윌4일)이 1946 μg/100 g, phydroxybenzoic acid는 상주둥시(5월29일)가 417.8 μg/100 g, protocatechuic acid는 갑주백목(6월1일)이 181.1 μg/l00 g으로 가장 많았다. 따라서 감꽃에도 감이나 감잎에 못지않게 유용한 식품성분들과 기능성 성분들이 다량 함유되어 있어 새로운 식품 및 기능성 신소재로서의 가치가 매우 높다고 할 수 있다. This study was carried out to analyze useful components in freeze-dried persimmon flower powder made from six cultivars. The cultivars were Dogunjosang, Kojongsi, Kabjubaekmok, Chalang, Weolhasi and SangjuDungsi. Powder of persimmon flower was prepared by milling after freeze drying at -70℃. Crude lipid was the highest in Dogunjosang (57.26%). Major free sugars of the persimmon flowers were fructose (95~310 mg%), glucose (75~281 mg%)and sucrose (7~28 mg%). Major organic acids were malic acid (225 mg% in Kabjubaekmok (Jun. 4th)) and tartaric acid (189 mg% in Kabjubaekmok (Jun. 4th)). Predominant free amino acids were hydroxy-L-proline(25.33 mg% in Weolhasi), L-citrulline (58.83 mg% in SangjuDungsi (May 28th)) and L-threonine (11.88 mg% in SangjuDungsi (May 28th)). Major phenolic compounds in the persimmon flowers were caffeic acid (1,946 μg/100g in Kabjubaekmok (Jun. 4th)), p-hydroxybenzoic acid(418 μg/100g in SangjuDungsi (May 29th)) and protocatechuic acid(181 μg/100g in Kabjubaekmok(Jun. 1st)). The results suggest that persimmon flowers be potential materials as useful food ingredients.

Clinical usefulness of infrared thermal imaging as a non-invasive screening test for diagnosis of vascular malformations

( Chihyeon Sohng ),( Jun Hong Park ),( Won Kee Lee ),( Jun Young Kim ),( Yong Hyun Jang ),( Weon Ju Lee ),( Seok-jong Lee ) 대한피부과학회 2018 대한피부과학회 학술발표대회집 Vol.70 No.2

Background: Infrared thermal imaging (ITI), aka thermography, has been used widely in medicine, but been studied rarely its clinical application in vascular malformations (VMs). Objectives: This study investigated validity and usefulness of ITI as a new screening test to differentiate between capillary malformation (CM) and arteriovenous malformation (AVM). Methods: This study included 50 patients with VMs who conducted ITI between 2011 and 2018. They were divided into two groups; CM and AVM, and those with Parkes-Weber syndrome (PWS) were also included in AVM group. Temperature difference (ΔT) between lesional and contralateral non-lesional area was compared using ITI to calculate the maximum ΔT (ΔTmax). The receiver operating characteristic (ROC) curve was then plotted to determine optimal cutoff value of ΔTmax. Results: Of the total 50 patients, 34 were finally diagnosed with CM, and 16 AVM (12 pure AVM, and 4 PWS). AVM group had significantly higher ΔTmax (2.57±1.23°C) than CM group (0.69±0.50°C).The area under the curve of ΔTmax for diagnosis of AVM versus CM was 0.938. The sensitivity and specificity were showed 87.5% and 94.1% (LR+, 14.87; LR-, 0.13) in cutoff value of ΔTmax 1.39°C, and 81.3% and 97.1% (LR+, 27.62; LR-, 0.19) in cutoff value of ΔTmax 1.42°C. Conclusion: The value of ΔTmax measured by ITI was useful to distinguish AVM from CM, so ITI can be employed as a new non-invasive differential screening test for uncertain VMs.

민간 경호·경비원들의 의식구조와 가치관에 관한 연구

박준석,최현식,정성숙,김진환,정석현 한국스포츠리서치 2004 한국 스포츠 리서치 Vol.15 No.4

The aim of this study was to investigate Consciousness and Value on Private Bodyguard and Security. I started to search from 7. January. 2004 to 20. May. 2004. so totally I searched for 5month, As a result, I got 526 papers of questionnaire and dropped 26 papers of them because of insincere answers from responders, So I used 500 papers for the research that I am doing. The method of One-Way ANOVA was used to verify the mean ratio and LSD multiple range test was also used for the verification when there was a slight difference among the objected group, All data were analyzed by SPSS 11.0 producer. The results of this study are like the below: 1) The result In the case of ages showed that significant difference(p<.05) companies consciousness were Private Bodyguard and Security for structure of consciousness. 2) The result In the case of Educational Credentials showed that no significant difference self consciousness, welfare conscious ness, social consciousness, companies consciousness were Private Bodyguard and Security for structure of consciousness. 3) The result In the case of work duration showed that significant difference(p<.05) self consciousness were Private Bodyguard and Security for structure of consciousness. 4) The result in the case of monthly income showed that no significant difference self consciousness, welfare conscious ness, social consciousness, companies consciousness were Private Bodyguard and Security for structure of consciousness. 5) The result in the case of working time showed that significant difference(p<.05) self consciousness, social consciousness, companies consciousness were Private Bodyguard and Security for structure of consciousness.

벼(Oryza sativa L.)배양세포에서 이차대사에 대한 숙주 특이성이 낮은 Elicitor의 영향

박준석,이인철 대전대학교 기초과학연구소 1997 自然科學 Vol.8 No.2

숙주 특이성이 낮은 elicitor에 대한 식물의 반응 기작을 이해하고자 벼(Oryza sativa L. cv. Nakdong)의 배양세포에서 yeast cell wall로 부터 추출한 elicitor의 영향을 조사하였다. 선행된 실험에서 장미(Rosa sp. L.) 배양세포에 대한 yeast elicitor의 영향은 extracellular peroxidase의 활성 증가라는 특징을 보여준 바 있다. 그러나 벼 배양세포에서 elicitor는 의 활성에 대한 영향이 거의 없는 것으로 관찰되었다. 반면 cinnamic acid 4-hydroxylase의 활성은 elicitor 투여 후 24시간 내에 40% 정도 증가하는 것으로 측정되었다. Phenylpropanoid pathway에 대한 elicitor의 영향은 선택적인 것으로 보여지며 특히 flavonoids계열의 화합물의 축적이 일어난다는 결과를 얻었다. 이상의 결과는 장미 배양세포에서 얻어진 결과와는 매우 상이한 것으로, 동일한 elicitor에 대하여서도 식물의 종에 따라 그 반응의 양상이 차이가 있음을 보여주고 있다. To understand the plant response mechanism against low host-specific elicitor, effects of elicitor prepared from yeast cell wall on secondary metabolism in cultured rice(oryza sativa L.) cells were investigated, In contrast to the characteristic enhancement of extracellular peroxidase activity in cultured rose cells by yeast elicitor as reported in previous work, there was no significant affect on peroxidases in cultured rice cells by the same treatment. Activity of cinnamic acid 4-hydroxylase, one of the key enzyme in phenylpropanoid pathway, increased up to 40% by the elicitor treatment within 24 hours concomitant with the total phenolics accumulation. among the phenylpropanoid metabolites flavonoid compounds seemed to be significantly accumulated in the elicitor treated rice cells. These results showed the different responses to the yeast elicitor according to the plant species.

한국 민간보안.시큐리티 산업의 발전방안

박준석 용인대학교 2006 용인대학교 논문집 Vol.24 No.-

The device for the important assignment of the healthy bringing up and the preservation of public peace should be examined, first in legal, systemic term, second the terms of quality improvement for security, guard, security guard, third the terms of cooperate important for private, security, guard, security guard, forth total security system expulsion, change of people, paradigm shift about private security , guard, crime prevention, expulsion and supporting. When considering real term, a policeman on special guard assignment system and private security guard , system's combining or unifying should be set up quickly to take a role of partner. Lastly, the access will be needed such as security industry's variety, speciality, education, guarantee of job, well fare etc like America lessen risk management system's loss, spread out. So, it is needed to access security total consulting industry, government, organization(military, police, security service, national intelligence service etc) and it is considered cooperate system of security company related area(education organization, academy world) and government organization (military, police, security service, national intelligence service) is very necessary soon. Risk management manual, D.B. expulsion should be variously developed.

국내기업의 테러위협국가 위협의 예방과 과제

박준석 용인대학교 인문사회과학연구소 2009 인문사회논총 Vol.- No.16

As a plan for protection and prevention of domestic enterprises, mutual intimate cooperation in the need to change perception of CEOs, the institutionalization of the companies' counter-terrorism measures system, the cooperation in international agreement or mutual assistance, the help of academic world and private security industries, the necessity for enactment of counter-terrorism laws, the status and directions against the terrorism and stationing and education of experts, and protection of exchanging cultures, sports, and education and visits should be formed. As an option for protecting domestic enterprises getting into state sponsors of terrorism against threat of terrorism, there is the necessity that National Intelligence Service (Integrated Center against Terrorism) organizes integrated management system with administrative organs which are related to itself such as KOTRA, KCCI, KITA, KOICA, embassies, consulate offices, the police, and the military. Moreover, as a protection, it is necessary to make experts at the terrors and security be on duty all times focusing on the state sponsors of terrorism such as Africa and the Middle East to not only prevent also restore and cope with terrorism. Following above, formating network of information of domestic companies entering into states sponsors of terrorism, and studying of cultural, religious, and linguistic parts have to be controlled under the national crisis management. Additionally, the long-termed mutual cooperation between domestic enterprises should be researched. Also, in resources diplomacy of current government, it is considered that the domestic industries' system of protection, prevention, confrontation, and recovery for legal, systematic, administrative, integrated crisis management should be gradually studied.

태권도 체육 수업에 대한 고등학생들의 인식도 조사 연구

박준석,조인철,고영철 한국스포츠리서치 2003 한국 스포츠 리서치 Vol.14 No.4

The purpose of this study is to establish the educational ideology of Taekwondo by basing on male and female high school students' interest level of Taekwondo in physical education class conducted in school. The subjects were 947 students, including 544 boys and 403 girls, from four different high schools in Gyeonggi province, Busan and Seoul, where Taekwondo lesson was offered. For data analysis, t-test was conducted to find out the differences between the boys and girls, and Chi-square test was used to verify the level of significance. The results from this study is listed as below: Firstly, for the nasality of Taekwondo in physical education, 31.7% answered "so-so" as the highest result. Secondly, concerning whether the educational objectives for each grade were selected to meet their expectations and needs, 38.5 percent found it not quite satisfying and also 34.0 percent of subjects were not considering themselves to be interactive or alert in Taekwondo class. Thirdly, concerning if Taekwondo in physical education is practicing both practical and theory, 36.0% answered "so-so", and concerning if Taekwondo related books are brief and logical so that it is easy to understand, 34.5% answered "so-so" as the highest result. Forthly, concerning if Taekwondo in physical education is helping improve their health and strength, 33.8% answered "so-so", and concerning if it is helping improve their manners and social relations, 34.3% answered "so-so" as well. Lastly, 41.9% perceived the related educational setting in their schools to be "so-so", and 32.7% perceived the improvement effort of conducting Taekwondo in physical education in school as "so-so".

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.

남ㆍ녀 중학생의 오래달리기를 통한 기록비교 연구

박종성,채준석,조기형 명지대학교 예술체육대학연구소 2004 藝體能論集 Vol.15 No.-

This study compared and analysed the physical factors and the average difference in a long distance race(male;1600m, female;1200m). The author(s) analysed students record according to their schools' location and examined that when their record difference become the biggest whether they did the warm up exercise or not. So this study purposed to offer the practical information to the P.E. teachers and leaders. Followings are the results; 1. There was no significant difference in a long distance race record according to the schools' location. 2. There was no significant difference in a long distance race record accordance with doing warm up exercise before the race in male group. But there was significance difference in female group. 3. There was no significant difference in a long distance race record in accordance with the physical factors(heights, weights and BMI). As a result of this study, there was no significant difference in a long distance race record accoerding to the schools' location in the average and the standard deviation. But it indicate that warm up exercise of the 1500m mountain race enhance the record without regarding of their physical factors. Before the class if they run 1500m mountain race as a worm up exercise it makes the significance difference according to the grades.