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.

새로운 DGS 구조를 이용한 발진기 구조에 대한 연구

박준석,정명섭 국민대학교 생산기술연구소 2003 공학기술논문집 Vol.26 No.-

This paper presents a novel defected ground structure (DGS) and its application to a microwave oscillator. The presented oscillator is designed so as to use the suggested defected ground structure as a feedback loop inducing a negative resistance as well as a frequency-selective circuit. Applying the feedback loop between the drain and the gate of a FET device produces precise phase conversion in the feedback loop. The equivalent circuit parameters of the DGS are extracted by using a three-dimensional EM calculations and simple circuit analy sis method. The implemented 8.94GHz oscillator exhibits 9 dBm output power with over 40% dc-to-RF power efficiency and -84.5dBc/Hz phase noise at 100 kHz offset from carrier.

민간경비업체의 인터넷마케팅 활용방안에 관한 연구

박준석,박규태 한국스포츠리서치 2003 한국 스포츠 리서치 Vol.14 No.6

Korean private security company's marketing by utilizing the Internet is still at the initial stage. It requires chief executive officer(CEO)'s consciousness structure and market environment. This study is aimed at presenting the plan for a private security company recognizing Internet marketing as a new change and utilizing it efficiently in on-line market through systematic and organizational management. The strategies for a private security company utilizing Internet marketing for this are presented as follows. First, a private security company should utilize its website in a strategic way. It should establish a new concept of marketing by which to command 4p's strategy as a marketing strategy. Secondly, a private security company should support its existing customers. It should continue to manage and operate its secured customers through its website in a saturated market. Thirdly, a private security company should cultivate organized professional manpower. The management should change their recognition, establish the department in charge of it, and cultivate professional manpower. Fourthly, a private security company should construct the database on its customers. It should be able to make database and utilize the information on its members and customers visiting its website.

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.

벼 乾沓直播栽培時 播種期가 乾物生産에 미치는 影響

朴栽成,朴成圭,李尙榮,洪性澤,池在浚,趙東三,孫錫龍 충북대학교 농업과학기술연구소 1999 農業科學硏究 Vol.16 No.-

This experiment was carried out to obtain indispensable information to establish comprehensive cultural method of rice in direct seeding on dry paddy at Chungbuk Agricultural Research and Extension Services. Effect of seeding date on dry matter production, yield components and yield were studied. Seeding on May 5 ensured the highest maximum number of tillers, while transplanting on May 20 gave the highest rate of effective tillers. Number of effective tillers was greater in the order of Hwajinbyeo, Hwaseongbyeo, Daekwanbyeo. Lengths of upper three leaves were increased at later seeding, but leaf width was not affected by seeding date. Ratio of leaf blade weight was higher in earlier seeding during 30 days before heading but was higher in later seeding during 30 days after seeding, and was higher in the order of Hwajinbyeo, Hwaseongbyeo, Daekwanbyeo. CGR, RGR and NAR were not significantly different among seeding dates during 30 days before heading, but were lower in later seeding during 30 days after seeding. LAR was not affected by seeding date during 30 days before heading, but was higher at seeding on May 5 in heading date and during 30 days after heading. Dry weight of leaf blade, leaf sheath and culm, ear and total biomass during 30 days before heading and heading were highest in May 5 seeding. Daekwanbyeo and Hwaseongbyeo in May 5 seeding and Hwajinbyeo in April 20 seeding brought the highest yield with greater number of spikelets, higher ripening ratio and greater 1,000 grain weight, and harvest index and grain/straw ratio were Increased at earlier seeding. There were significantly positive correlations between number of panicles per m2 and LAI at 30 days before heading and heading, dry matter weight of leaf blade and total mass at heading. On the other hand, there were significantly negative correlations between seeding date and ripened grain ratio. 1,000 grain weight and yield, and between 1,000 grain weight and leaf length of 2nd, respectively.

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.

경부 청소술 후의 승모근기능

박준명,박동식,정광익,이언석,노영수 大韓再活醫學會 1998 Annals of Rehabilitation Medicine Vol.22 No.2

한국에서 온라인서비스제공자의 법적 책임론이 나아갈 방향

박준석 慶熙大學校 경희법학연구소 2008 경희법학 Vol.43 No.3

The legal theory or regulation on the secondary liability of Online Service Provider is roughly divided into two parts, liability requirement and liability limitation requirement. For the OSPs’ liability requirement portion, Korean court seems to have taken unified position in both users’ copyright infringement case and defamation case, pointing out that Joint Tort-feasors rule in Article 760, Clause 3 of the Korean Civil Act is the statutory ground for OSPs liability requirement. For the liability limitation portion, meanwhile, there has been inconsistency of liability limitation requirement in Korean Copyright Act and The Act on Promotion of Information and Communications Network Utilization and Data Protection, thereby making OSPs in Korea suffer from unnecessary legal uncertainty. OSPs’ secondary liability rules in Korea should not follow the US model in which it has been traditionally divided between copyright infringement and defamation. Korea has not differentiated copyright infringement case from other infringement cases including defamation in the secondary liability requirement portion, whereas US has done. Moreover, it can’t be missed that there is a plausible argument for the unification of OSPs’ liability limitation rules even in US. Therefore, OSPs’ secondary liability rules in Korea should be unified over all infringement areas by users, regardless of copyright infringement, defamation, etc., to settle the legal uncertainty in Korea, mentioned above. While the best way would be a new unified law on OSPs’ secondary liability limitation, if it would be severely hard, the second best way to do so is to make immediate amendments harmonizing OSPs’ liability limitation clauses in both acts, Korean Copyright Act, Article 102 & 103 and the Act on Promotion of Information and Communications Network Utilization and Data Protection, Article 44-2. It’s a wrong conception at least in OSPs’ secondary liability area, the way of thinking that defamation cases related to the freedom of speech should be treated differently from copyright infringement cases at all times. In addition, the following differences just can be merely secondary considerations, but never make it very hard to unify OSPs’ secondary liability rules; i) online defamation is usually done through Bulletin Board System rather than Peer to Peer network which has been one of main devices for online copyright infringement, ii) it’s harder in online defamation case to judge the legality of the information at issue and control illegal information than in online copyright infringement case, iii) there is a relatively stronger need to identify direct infringers in online defamation than in online copyright infringement because the former case has relatively fewer infringers than the latter and only the former case has irreparable harm which can’t be compensated by monetary remedies.