Improvement of Desulfurization Efficiency via Numerical Simulation Analysis of Transport Phenomena of Kanbara Reactor Process

Yong‑Joon Lee,Kyung‑Woo Yi 대한금속·재료학회 2022 METALS AND MATERIALS International Vol.28 No.4

The Kanbara reactor (KR) process is a mechanical stirring method that reacts hot metal with desulfurization flux; it is a widelyimplemented desulfurization method in contemporary steel production. This study aimed to develop a new impeller profilefor improving the desulfurization efficiency of the KR process. We implemented operational data analysis, a computationalfluid dynamics simulation based on the operational data and performed testing and analysis with impeller models on-site aproduction facility. Operational data from the production facility was gathered over a 3-year period. Seven impeller modelswith varying impeller blade width (top and bottom), height, inclination, and curvature (curved, straight, and combination)were simulated. The results were analyzed to determine the optimal conditions. A new impeller design was selected for onsiteoperational testing to investigate the in situ desulfurization efficiency over 350 charges, and the results corroborated thepredictions by the numerical simulations. It is expected that the proposed process modification can be successfully used forimproving industrial desulfurization efficiency.

Light-extraction efficiency control in AlGaN-based deep-ultraviolet flip-chip light-emitting diodes: a comparison to InGaN-based visible flip-chip light-emitting diodes.

Lee, Keon Hwa,Park, Hyun Jung,Kim, Seung Hwan,Asadirad, Mojtaba,Moon, Yong-Tae,Kwak, Joon Seop,Ryou, Jae-Hyun Optical Society of America 2015 Optics express Vol.23 No.16

<P>We study light-extraction efficiency (LEE) of AlGaN-based deep-ultraviolet light-emitting diodes (DUV-LEDs) using flip-chip (FC) devices with varied thickness in remaining sapphire substrate by experimental output power measurement and computational methods using 3-dimensional finite-difference time-domain (3D-FDTD) and Monte Carlo ray-tracing simulations. Light-output power of DUV-FCLEDs compared at a current of 20 mA increases with thicker sapphire, showing higher LEE for an LED with 250-관m-thick sapphire by ~39% than that with 100-관m-thick sapphire. In contrast, LEEs of visible FCLEDs show only marginal improvement with increasing sapphire thickness, that is, ~6% improvement for an LED with 250-관m-thick sapphire. 3D-FDTD simulation reveals a mechanism of enhanced light extraction with various sidewall roughness and thickness in sapphire substrates. Ray tracing simulation examines the light propagation behavior of DUV-FCLED structures. The enhanced output power and higher LEE strongly depends on the sidewall roughness of the sapphire substrate rather than thickness itself. The thickness starts playing a role only when the sapphire sidewalls become rough. The roughened surface of sapphire sidewall during chip-separation process is critical for TM-polarized photons from AlGaN quantum wells to escape in lateral directions before they are absorbed by p-GaN and Au-metal. Furthermore, the ray tracing results show a reasonably good agreement with the experimental result of the LEE.</P>

정신분열병에 대한 리스페리돈의 효과 및 안정성

이민수,김용구,김영훈,연병길,오병훈,윤도준,윤진상,이철,정희연,강병조,김광수,김동언,김명정,김상훈,김희철,나철,노승호,민경준,박기창,박두병,백기청,백인호,손봉기,손진욱,양병환,양창국,우행원,이정호,이종범,이홍식,임기영,전태연,정영조,정영철,정인과,정인원,지익성,채정호,한상익,한선호,한진희,서광윤 大韓神經精神醫學會 1998 신경정신의학 Vol.37 No.1

연구목적 : 본 시험의 목적은 임상시험 시작전에 연구자들을 대상으로 PANSS Workshop을 통하여 PANSS, ESRS에 대한 국내에서의 표준화 작업을 구축하고 새로운 정신병 치료제인 리스페리돈의 효과와 안정성을 재확인하여 리스페리돈 사용에 대한 적정화를 이루는데 있다. 연구방법 : 1996년 4월부터 1996년 9월까지 국내 39개 대학병원 정신과에 입원중인 혹은 증상이 악화되어 입원하는 정신분열병 환자 377명을 대상으로 다시설 개방 연구를 시행하였다. 1주일간의 약물 배설기간을 가진후, 리스페리돈을 8주간 투여하였고, 기준점, 1주, 2주, 4주, 그리고 8주후에 평가되었다. 용량은 제1일에는 리스페리돈 1mg씩 1일 2회, 제2일에는 2mg씩 1일 2회, 제3∼7일에는 3mg씩 1일 2회 투여하였다. 이후 환자의 임상상태에 따라 임의로 증량할 수 있으며, 최대 일일 16mg을 초과하지 않도록 하였다. 추체외로 증상을 조절하기 위한 투약을 허용하였다. 임상증상 및 부작용의 평가는 PANSS(Positive and Negative Syndrome Scale), CGI(Clinical Global Impression) 그리고 ESRS(Extrapyramidal Symptom Rating Scale)을 사용하였다. 연구결과 : 377명중 343명(91%)이 8주간의 연구를 완결하였다. 치료 종결시점인 8주후 PANSS 총점수가 20% 이상 호전된 경우를 약물 반응군으로 정의할때, 약물반응군은 81.3%였다. 리스페리돈에 반응하는 예측인자로는 발병연령, 이전의 입원 횟수, 유병기간이 관련 있었다. 리스페리돈은 1주후부터 PANSS양성, 음성, 및 일반정신병리 점수상에 유의한 호전을 보여 효과가 빨랐다. CGI의 경우도 기준점에 비해 1주후부터 유의한 감소를 나타내었다. ESRS의 경우, 파킨슨 평가점수는 기준점과 비교해 투여 1주, 2주, 4주후 유의하게 증가되었다가 8주후 기준점과 차이가 없었다. Dystonia 평가점수는 1주후만 유의한 증가를 보였으며, dyskinesia 평가점수는 유의한 차이가 없었다. 혈압, 맥박수의 생명징후 및 일반 혈액학 검사, 생화학적 검사, 심전도 검사에서 유의한 변화는 없었다. 결 론 : 이상의 다시설 개방 임상 연구를 통해 리스페리돈은 정신분열병 환자에서 양성증상뿐만 아니라 음성증상 및 전반적인 증상에도 효과적인 것으로 사료된다. 보다 명확한 평가를 위해서는 다른 항정신병약물과의 이중맹검 연구가 필요할 것으로 생각되며, 또한 장기적 치료에 대한 평가도 함께 이루어져야 하겠다. Objective : The purpose of this study was to investigate the efficacy and safety of risperidone in the treatment of Korean schizophrenic patients. Method : This multicenter open study included 377 schizophrenic patients drawn from 39 university hospitals. After a wash-out period of 1 week, the schizophrenic patients were treated with risperidone for 8 weeks and evaluated at 5 points ; at baseline, and 1, 2, 4 and 8 weeks of treatment. The dose was increased from 2mg/day(1mg twice daily) to 6mg/day(3mg twice daily) during the first week and adjusted to a maximum of 16mg/day over the next 7 weeks according to the patient's clinical response. Medication to control extrapyramidal symptoms was permitted. The psychiatric and neurological status of the patients was assessed by PANSS, CGI, and ESRS scales. Results : 343(91%) of 377 patients completed the 8-week trial period. Clinical improvement, as defined by a 20% or more reduction in total PANSS score at end point, was shown by 81.3% of patients. The predictors of response to risperidone were associated older age, shorter duration of illness, fewer previous hospitalization. Risperidone had rapid onset of action ; a significant decrease of the total PANSS and three PANSS factor(positive, negative, general), and CGI was already noticed at the end of first week. For the ESRS, parkinsonism rating scores were significantly increased until week 4 comparing with baseline. Dystonia rating scores were significantly increased until week 1, and dyskinesia rating scores were not significantly changed during the study. Laboratory parameters including vital sign, EKG, hematological, and biochemical values showed no significant changes during the trial. Conclusions : This study suggests that risperidone is generally safe and effective against both the positive and negative symptoms in our group of patients.

수근관 증후군에서의 무증상성 척골신경병증

문준식,이성수,이지용,한범기,권준범,양현덕,이성익 대한신경과학회 1999 대한신경과학회지 Vol.17 No.2

서울의 Penicillinase Producing Neisseria gonorrhoeae 발생빈도(1998)

김재홍,김준호,반재용,이정우,황성주,정준규,정성태,강진문,조흔정,홍창의,정혜신,이한승,김이선,이봉길,이종호,선영우,한기덕,윤성필,이성훈,안종성,박석범,문승현,조항래,김형섭,류지호,황재영,박준홍,손상욱 한양대학교 의과대학 2001 한양의대 학술지 Vol.21 No.1

In recent years, gonorrhea has been pandemic and remains one of the most common STDs in the world, especially in developing countries. For the detection of a more effective therapeutic regimen and assessing the prevalence of Penicillinase Producing Neisseria gonorrhoeae(PPNG), we have been trying to study the patients who have visited the Venereal Disease Clinic of Choong-Ku Public Health Center in Seoul since 1980 by menas of the chromogenic cephalosporin method. In 1998, 93 strians of N. genorrhoeae were isolated, among which 60(64.5%) were PPNG. The prevalence of PPNG in Seoul, which had been decreased to 39% in 1996 after a peak of 74.3% in 1993, is increased to 64.5% in 1998.

서울의 Penicillinase Producing Neisseria Gonorrhoeae 발생빈도(1996)

김재홍,황동규,전재홍,김윤석,김중환,김용준,이창균,임동진,김현수,조창근,김경문,박상훈,전우형,김희성,이호정,차명수,김갑형,김형석,김석우,황지환,박병순,권오상,이민수,송기훈,성소영,이인섭,부태성 대한화학요법학회 1999 대한화학요법학회지 Vol.17 No.2

Background : In recent years, gonorrhea has been panedemic and remains one of the most commom STDs in the world, especially in developing countries. Objective & Methods: For the detection of a more effective therapeutic regimen and assessing the prevalence of PPNG, we have been trying to study the patients who have visited the VD Clinic of Choong-Ku Public Health Center in Seoul since 1980 by means of the chromogenic cephalosporin method. Results: In 1996, 139 strains of N. gonorrhoeae were isolated, among which 53(39.0%) were PPNG. Conclusion: Our results suggests that after a peak of 74.3% in 1993, the prevalence of PPNG in Seoul is gradually declining.

졸-겔법에 의한 Mullite 코팅막의 제조 및 특성에 관한 연구

이용택,최영우,양중식 慶熙大學校 材料科學技術硏究所 1997 材料科學技術硏究論集 Vol.10 No.-

출발원료로 알루미늄 세크 부톡사이드(ASB)와 테트라 에톡시실란(TEOS)을 사용하는 졸-겔법에 의해 뮬라이트 조성의 졸 용액을 제조하고, 지지체 표면위에 침지 시간의 변화에 따라 코팅을 실시하였다. 그 결과 뮬라이트 결정화를 위해서는 1,300℃이상의 열처리 조건으로 균열 없는 뮬라이트 코팅막을 제조하는 것이 가능하였으며 침지시간에 따라 코팅막의 두께가 선형적으로 증가하고 평균 기공의 크기는 20∼30Å까지 기공 제어가 가능하였다. Optimal Mullite sol was synthesized by sol-gel process using Aluminium sec-butoxide(ASB), Tetraethoxy-silane(TEOS) and then, Mullite films were dip-coated with various holding time in sol bath and heat-treated at 1300℃ above for crystallization. The thickness of coated film increased linearly with holding time in sol bath and average pore size was controllable within 20-30Å.

Captopril과 Nifedipine 병합요법의 강압효과에 관한 임상적 연구

이영수,문언수,김준호,공수정,정시진,주용진,정상만 건국대학교 의과학연구소 1993 건국의과학학술지 Vol.3 No.-

Background: The hypotensive effect of captopril(angiotensin converting enzyme inhibitor) and nifedipine(calcium channel blocker) was studied. Method: Captopril(75mg) and nifedipine(30mg) were administered in 30 hypertensive adults during twelve weeks after a week observation for washout with stepwise increments of the dose according to the patient's blood pressure in every two weeks. Result: The supine blood pressure were decreased from 169.5±22.3/104.0±20.3 mmHg to 130.4±21.3/82.4±19.5mmHg at the end of twelve weeks during therapy.(p<0.05) The standing blood pressure were also decreased conferrably and to the some lower level. Hematologic examination and blood chemistry revealed no discernible abnormal findings before and after the treatment. During the period of the study a few probably drug-related symptom such as cough and headache, gastrointestinal disturbance developed but not troublesome enough to administering. Conclusion: Captopril and nifedipine regimen is well tolerated and effective in the treatment of hypertensive patients.

親生子鑑別에서 多座位 探針으로 檢索되는 共有 遺傳子指紋의 意義

李羲碩,金希宣,南容碩,李惠麟,黃迪駿 大韓法醫學會 1995 대한법의학회지 Vol.19 No.1

Conventional paternity index and probability of paternity can not be calculated when probe that hybridize to multiple VNTR loci because alleles are not ascertained to specific loci. Therefore, an alternate method based upon the chance of band-sharing used to get paternity index and probability of paternity in this study using multi-locus pV47-2 probe. From 57 parentage cases of Korean pedigree we found 12.08, 11.86, and 12.31 of average DNA fingerprints present in mother, father and child., respectively. Among 614 DNA bands present in 57 children, 7 bands are not assignable to neither number of bands shared between nother and father is 1.71, with mean band-sharing coefficiency of 0.1798. All bands present in the child's pattern but absent in the mother's are 5.14 on average as obligator paternal band, but a child are transmitted 5, 47 from mother. In 10 non-parentage cases, however, a child shared bands of 1.20 on average with a putative father, whereas shared bands of 5.60 with a biological mother. In the paternity test of a child having 3 bands of obligatory paternal origin, paternity index(PI) and probability of paternity(PP) are calculated with the band0sharing coefficiency of 0.18 as 21.4, and 95.4%, respectively. These results suggest that RFLP analysis using multi-locus pV47-2 probe could identify with virtual certainty one particular man as the biological father of a child.

Olanzapine 복용 이후 당뇨병 케톤산증이 발생한 정신분열병 환자

이중선,김진용,안준호,김창윤 大韓神經精神醫學會 2005 신경정신의학 Vol.44 No.1

The use of olanzapine has been associated with clinically significant hyperglycemia (exacerbation of existing diabetes, new-onset type 2 diabetes and diabetic ketoacidosis). We report a case of diabetic ketoacidosis (DKA) in 30-year-o1d male patient with schizophrenia who was on olanzapine. When he was admitted to the hospital because of DKA, he had been taking olanzapine for 43 months. 14 months before the admission, his fasting and 2 hour postprandial serum glucose levels were normal. He had no personal and family history of diabetes mellitus. He had no risk factor for diabetes mellitus except for obesity (body mass index : 39.2 kgW). He also hadno precipitating factors for DKA such as infection or myocardial infarction. Periodic monitoring for changes in serum glucose levels in patients taking olanzapine may be needed.