Effects of the Ultrasound Treatment on Reaction Rates in the RH Processor Water Model System

Yong‑tae Kim,Kyung‑woo Yi 대한금속·재료학회 2019 METALS AND MATERIALS International Vol.25 No.1

Ruhrstahl–Heraeus (RH) processor is widely applied to the refining process to produce steel with very low carbon contents. In this study, to investigate the effect of ultrasound treatment on RH decarburization process, we have developed two kinds ofthe water models simulated the RH process and study the removal rate of dissolved oxygen. The one is the RH water modelof 1/8 size of actual RH degasser simulated the late-stage of the RH process when surface reaction and plume reaction mainlyoccur. Through this model, it is found that the ultrasound treatment accelerates dissolved oxygen removal reaction and thistendency is maintained even at low concentrations. Also, the results show that there is a difference in the degassing efficiencydepending on the frequencies and the positions of the ultrasonic transducer. Also, to simulate the Early-stage Reaction ofthe process including the inner-site reaction which is difficult to investigate through the RH water model, the other watermodel has been developed (the RH-ER water model). This model shows that the ultrasound treatment facilitates the earlystagereaction including inner-site reaction, like the RH water model. These results show that the addition of the ultrasoundtreatment can accelerate decarburization reaction during RH process compared to conventional process.

Effects of Variation of Heat Flux Released from the Meniscus on the Surface Shape of the Solidified Shell During Continuous Casting

Yong‑tae Kim,Kyung‑woo Yi 대한금속·재료학회 2021 METALS AND MATERIALS International Vol.27 No.12

Mold oscillations, widely used in continuous casting for infiltrating the mold flux between the mold and the solidified shell,change periodically the heat flux from the meniscus to mold. These variations of the heat flux affect the solidification behaviornear an initial solidification position. Because the surface shape of the solidified shell is influenced by the initial solidificationbehavior, it is important to understand the relation between the mold oscillation, the heat flux and initial solidificationbehavior. In the present study, we developed a numerical model that simulates the flow and thermal behavior of the moldflux near the meniscus. Using this model, we analyze the effects of the variations of the heat flux from the meniscus on theinitial solidification position and suggest the formation mechanism of the oscillation marks (OMs) and the hooks. Also, wewill present quantitative results about the depth of the OMs and the length of the hooks at the conditions used in the presentstudy. The factors that influence the hooks’ types and the causes of the irregularity of the shell surface are also discussed.

여성 요도증후군에서 Terazocin의 효과에 대한 연구

우승효,신관희,한광희,정원일,이형래,이상철,김용태,김원재 충북대학교 의학연구소 2000 忠北醫大學術誌 Vol.10 No.2

연구목적: 여성 요도증후군을 보이는 환자에서 교감신경차단제인 terazocin을 복용한 후 치료 효과에 대한 각 증상의 변화와 부작용을 알아보고자 하였다. 대상 및 방법: 1997년부터 1999년까지 충북대학교병원 비뇨기과에 내원한 35명의 여성 중 요검사 및 요배양 검사, 그리고 다른 이학적 검사에서 이상이 없는 요도증후군 환자를 대상으로 간질성방광염 증상점수(ICSS)를 terazocin (3mg/day for 3 months) 투여 전후에 조사하였고, 치료 후 3개월과 1년에 Likert scale 점수를 조사하였다. 결과: ICSS는 비치료군은 18.3±5.9점, 치료군은 16.5±6.8점으로 두군간의 차이는 없는 것으로 나타났다(p=0.52). 치료군은 치료 후 3개월에 시행한 ICSS가 9.9±7.8점으로 치료 전에 비해 현격히 증상이 호전되는 것으로 나타났다(p=0.0001). 특히 3개월에 시행한 Likert scale에서는 주간 및 야간빈뇨, 절박뇨, 배뇨통의 횟수 및 강도, 그리고 전체적인 증상정도에서 40-70% 가량 호전된 것으로 밝혀졌으며 이는 1년 후에도 증상의 호전이 지속되는 것으로 나타났다. 비치료군에서의 1년 후 Likert scale은 6명 중 2명이 전체적인 증상의 호전이 있는 것으로 나타났다. 결론: Terazocin은 환자의 약 70%가량에서 증상의 호전을 가져왔고, 비치료군에서도 환자의 33%가 저절로 증상이 좋아진 것으로 보아 Terazocin은 여성 요도증후군에서 분명히 효과가 있으나 증상이 심할 경우 보조적인 치료로 이용되는 것이 바람직할 것으로 사료된다. Purpose: We performed to assess the effects and complications of terazocin in women with chronic female urethral syndrome. Materials and Methods : Thirty-five women with chronic female urethral syndrome were studied from March 1997 to August 1999. The subjects exhibited normal findings without the pyuria and bacteriuria in urinalysis and urine culture and were invested the interstitial symptom score(ICSS). 29 subjects of them took a terazocin 1-4 mg/day for 3 months. They were reevaluated for the ICSS and Likert scale after 3 months and for Likert scale after 1 year. Results: The ICSS before treatment were showed 18.3±5.9 in the untreated patient group and 16.5±6.8 in the treated patient group, and no statistically difference between both patient groups(p=0.52). In the treated patient group, the ICSS after treatment were showed 9.9±7.8, significant difference between before and after treatment(p=0.0001). The Likert scale was showed at 3 months after treatment that frequency, nocturia, urgency, pain frequency, pain intensity, daily activities, and overall symptoms were improved in 65.5%, 55.2%, 24.1%, 41.4%, 41.4%, 70%, 70%, and 70% of 29 subjects, each other. Overall symptom score assessed at 1 year were showed that 3 subjects was aggravated. In untreated patient group, 2 of 6 was improved in overall symptom score. Conclusion: Terazocin was effective above 70% in the treated group, and symptoms were improved spontaneously in a third of the untreated group. So, we thought that terazocin would be useful as supportive treatment in period of severe symptoms.

分散 데이타베이스 시스템에서의 相互不一致發見 및 再調整 알고리즘

禹容泰 國立 昌原大學校 産業技術硏究所 1987 産技硏論文集 Vol.1 No.-

In many cases it is desirable to keep redundant copies of critical resources such as files in distributed database systems. Although redundancy increases reliability and availability, it leads to mutual consistency problems when network partitions occur. This paper describes a mechanism to detect mutual inconsistency by using the modified version vector mechanisms which detailed update operation and suggests a method to reconcile these conflicts efficiently.

정현추종 제어기를 이용한 전압형 PWM 컨버터의 입력전류제어

우정인,정기화,최선영,허태원 東亞大學校 附設 情報通信硏究所 1999 情報通信硏究所論文誌 Vol.7 No.1

This paper presents the sinusoidal tracking controllr in order to eliminate the steady state control error and to improve the transient characteristics for input current in voltage source PWN congerter. A general mathematical model with switching functions of the PWM converter that is represented as differential equation is established. The proposed model in current control system that does not require coordinate transformations is described. It is proved that the steady state deviation reduces to zero from a transfer function of input current control system. The sinusoidal tracking controller is realized by differential equations for the LC equivalent circuit. From simulations and experimental work, it is verified that the control system can eliminate the steady state error of input current and also improve the transient state characteristic.

경북 일원의 포유류상

우용태,이종남,허위행 慶星大學校 1998 論文集 Vol.19 No.2

1. This is a part of the second nation-wide survey of natural environment by the Ministry of Environment of Korea in 1997 and the Mammalia were surveyed in the area of Daegu and Dalsung. 2. The survey area was divided into 6 parts and the survey was carried out by the visiting and inquiry method. 3. The Mammalia surveyed were classified into 6 orders, 12 familiesm and 27 species. 4. A total of 27 species surveyed by this survey was only 35.5% of 76 species of Mammalia (except CETACEA and PINNIPEDIA) inhabited in Korea. 5. Among the 27 species, 17 species were surveyed at all the 6 parts, 3 species were natural monuments, and 7 species were rare and endangered species. 6. The result showed that several species decreased because of the destroy of habitat by the deforestation and illegal capture.

Genome-wide investigation of a Korean synthetic breed, Woori-Heukdon using the Illumina PorcineSNP60K BeadChip

Yong‑Min Kim,Ha‑Seung Seong,Jung‑Jae Lee,Da‑Hye Son,Jin‑Su Kim,Soo‑Jin Sa,Young‑Sin Kim,Tae‑Jeong Choi,Kyu‑Ho Cho,Joon‑Ki Hong,Jung‑Woo Choi,Eun‑Seok Cho 한국유전학회 2020 Genes & Genomics Vol.42 No.12

Background: Woori-Heukdon (KWH) is a Korean synthetic pig breed generated using Chookjin-Duroc (KCD), Chookjin-Chamdon (KCC), and their crossbreds. Currently, there is a severe lack of studies investigating the Korean breed populations including wild boars (KWB) throughout the genome. Objective: This study was performed to investigate the genetic characteristics of Korean pig populations at the genome-wide level. Methods: Using the SNP dataset derived from genotyped and downloaded datasets using the Illumina PorcineSNP60K BeadChip, we compared the genomes of 532 individuals derived from 23 pig breeds to assess the genetic diversity, inbreeding coefficient, genetic differentiation, and population structure. Results: KWB showed the lowest average expected heterozygosity (HE = 0.1904), while KWH showed the highest genetic diversity (HE = 0.02859) among Korean populations. We verified that the genetic composition of KWH, showing USD of 74.8% and KCC of 25.2% in ADMIXTURE analysis. In population structure analyses, KCC was consistently shown to be separated from other pig populations. In addition, we observed gene flow from Western pigs to a part of Chinese populations. Conclusion: This study showed that Korean native pigs, KCC have genetic differences in comparison with Chinese and Western pigs; despite some historical records and recent genetic studies, we could not find any clear evidence that KCC was significantly influenced by Chinese or Western breeds in this study. We also verified the theoretical genomic composition of KWH at the molecular level in structure analyses. To our knowledge, this is the first genomic study to investigate the genomic characteristics of KWH and KCC.

체인가시성에 관한 최적 알고리즘

우용태,엄종훈 國立 昌原大學校 基礎科學硏究所 1993 基礎科學硏究所論文集 Vol.4 No.-

In this paper, given a simple polygon and a simple chain ch(??,??), the notion of chain visibility polygon of a simple polygon P is introduced, and a optimal algorithm for finding the chain visibility polygon in a simple polygon is presented. In the preprocessing step, the simple polygon is triangulated, and computed shortest paths from ?? and ?? to all other vertices in linear time. Then, Condensed dual tree composed of triangles of triangulation is traversed and visible areas from the chain is computed and merged in linear time.

대장암 환자에서의 담즙 암태아성 항원(CEA)

김종우,박용태,정철운,권성원,장항석,손석우,안대호,이경포 대한대장항문학회 2000 Annals of Coloproctolgy Vol.16 No.6

경북 일원의 양서 . 파충류상

우용태,이종남,허위행 慶星大學校 1998 論文集 Vol.19 No.2

1. This is a part of the second nation-side survey of natural environment by the Ministry of Environment of Korea in 1997 and the Amphibians and Reptiles were surveyed in the area of Daegu and Dalsung. 2. The survey area was divided into 6 parts and the survey was carried out by the visiting and inquiry method. 3. The Amphibians surveyed were calssified into 2 orders, 6 families and 9 species, and Reptiles were classified into 2 orders, 6 families and 14 species, respectively. 4. Among the 23 species, 16 species, were surveyed at all the 6 parts. And among the surveyed species, 10 were rare or endangered species. 5. The result showed that several species decreased because of the destroy of habitat by the deforestation, overcatching for the materials of Korean medicine, and especially the prey by introduced foreign species-Rana catesbiana. 6. Elaphe schrenckii distributed in some areas and Gekko japonicus, having been reported extinct after 1920, distributed in Mt. Pi-suhl, Chung-ryong, and Choi-jung.