업셋단조에서의 국부화에 관한 연구

이병섭,황두순,홍성인 충남대학교 산업기술연구소 2003 산업기술연구논문집 Vol.18 No.1

It is difficult to predict material behavior of forming process, because the plastic instable flow happens in practical forming process, i. e. upsetting, backward extrusion, piercing, indentation. In view of the direct relationship between material flow and defects of the products, we should find out its mechanism. In this study, we introduced the plastic spin and the kinematic hardening and considered the kinematic hardening constitutive equation for rate-dependent material. Also analysis of upset forging is carried out using the rigid plastic FEM with Al7075. Then, the results from the numerical analysis shows that kinematic hardening model results in more significant strain localiztion than isotropic hardening model.

성인 음낭수종의 치료로서 Window Operation의 효용성

서병욱,박영호,이남규,전윤수,김민의,김영호,송윤섭,구자현 순천향의학연구소 1999 Journal of Soonchunhyang Medical Science Vol.5 No.1

We intended to determine the usefulness of window operation for adult hydrocele repair. We reviewed medical records of 132 patients from January 1995 to June 1998 with primary hydrocele and evaluated complications and recurrence rates of eversion and/or excision, plication, and internal drainage technique. Recurrence rate was highest in internal drainage technique as 85.2%, and those of eversion and/or excision and plication technique were 1.3% and 4%, respectively. Complication rate was highest in eversion and/or excision technique, and lowest in internal drainage technique. Although complication rate was lowest in window operation, this operation could not be successful due to high recurrence, and we suggest that this operation should be abandoned for hydrocele repair.

有限要素法을 이용한 LNG선박용 배관의 응력해성에 관한 硏究

박선준,이병섭,홍성인 충남대학교 산업기술연구소 2001 산업기술연구논문집 Vol.16 No.1

The purpose of this study is to investigate the stress on the piping for LNG ships by using the Finite Element Method. By this method, we can estimate the working displacement, force and stress at each nodal point of equipped LNG piping. The results of the numerical analysis of piping for LNG ships are calculated. Through the analysis results and the comparison, the following conclusions are obtained ; (1)The weights of LNG and piping should be considered for calculating the stress on the piping of LNG Ships. (2)Sun effect should be considered for calculating the stress on the piping of LNG Ships. (3)The equipped LNG piping satisfy the relevant requirements of the IGC Code since the maximum stress, 17.3kg/mm2 at the elements of No.3 and No.12 for LNG piping sampled, is less than the allowable stress, 27.5kg/mm2 (4)To get more detailed stress value for the future, an additional study is necessary for dynamic load(for example, acceleration etc.,).

무증상의 현미경적 혈뇨의 비뇨기과적 고찰

구자현,서병욱,김영호,송윤섭,전윤수,김민의,이남규,박영호 순천향의학연구소 1998 Journal of Soonchunhyang Medical Science Vol.4 No.2

We intended to know whether all of the patients with asymptomatic microscopic hematuria should be urologically investigated routinely. We reviewed the medical records with asmptomatic microscopic hematuria from January 1995 to December 1997. Urological studies included intravenous urography or ultrasonography, urine cytology, cystoscopy and biopsy, urine AFB smear and culture and urine PCR for AFB. The age with patients ranged from 9 to 74 years(mean age: 39.7 years). Benign diseases were found in elderly patients and patients with high degree of hematuria, but there was no patients who had urological malignant disease. According to the results, we suggest that follow-up with urine cytology is sufficient to younger patients or low degree of hematuria with asymptomatic microscopic hematuria.

돌로마이트 슬러지를 이용한 세라믹스 제조

한상목,강상규,이승섭,이병민 강원대학교 석재복합신소재제품연구센터 1998 석재연 논문집 Vol.3 No.-

돌로마이트 폐기물 슬러지에 Al(OH)₃와 SiO₂를 첨가하여 코디어라이트와 규회석을 합성하고자 하였으나 1250℃소성으로 코디어라이트는 MAS조성에서 합성되지 않았으며 규회석은 합성이 되었다. 돌로마이트 내화물의 내수화성을 증가시키기 위해 슬러지에 Fe₂O₃를 6%이상 첨가하여 소성한 결과 입계에 (Ca·Mg·Al·Fe)SiO₂의 생성으로 인하여 내수화성이 증가되었다. The possibility of synthesis for the cordierite and wollastonite with dolomite waste sludge, Al(OH)₃ and SiO₂ was studied. With the composition of MAS, the cordierite was not synthesized at sintering of 1250℃ and the wollastonite was made at the same temperature. The addition of Fe₂O₃ above 6% to the dolomite for the antislaking behavior has promoted the sinterability of dolomite and (Ca·Mg·Al·Fe)SiO₂ at grain boundary was affecting the increase of antislaking.

여성 하부요관석환자에서 무마취하 요관경하 배석술

박영호,송윤섭,임용순,김영호,이남규,구자현,서병욱,김민의,전윤수 순천향의학연구소 1999 Journal of Soonchunhyang Medical Science Vol.5 No.2

Although ureteroscopy(URS) has been used widely to remove ureteral calculi, there is an argument against the belief that anesthesia or admission is needed for URS. We evaluated the experience of URS without anesthesia in female patients. From September 1997 to July 1998, URS was performed in 31 female patients without anesthesia. EHL(Electrohydraulic Lithotripsy) was used in 21 patients with impacted or large stone over 5mm. All patients were given oral antibiotics for 3 days and follow-up KUB was taken to confirm successful removal of the stone one week after the procedure. Successful treatment was defined as complete removal of the stone or residual fragments less than 2mm. Overall success rate was 96.7%(30 cases among 31 cases). All but one patient tolerated with analgesia through the entire procedures. There were only minimal complications such as mild flank pain and hematuria. So, we recommend that non-anesthetic ureteroscopic removal of stone as the first choice for treatment of lower ureteral stones in female based on the minimal morbidity, high success rate and low cost.

Engineering Titanium Dioxide Nanostructures for Enhanced Lithium-Ion Storage

Lee, Dae-Hyeok,Lee, Byoung-Hoon,Sinha, Arun K.,Park, Jae-Hyuk,Kim, Min-Seob,Park, Jungjin,Shin, Heejong,Lee, Kug-Seung,Sung, Yung-Eun,Hyeon, Taeghwan American Chemical Society 2018 JOURNAL OF THE AMERICAN CHEMICAL SOCIETY - Vol.140 No.48

<P>Various kinds of nanostructured materials have been extensively investigated as lithium ion battery electrode materials derived from their numerous advantageous features including enhanced energy and power density and cyclability. However, little is known about the microscopic origin of how nanostructures can enhance lithium storage performance. Herein, we identify the microscopic origin of enhanced lithium storage in anatase TiO<SUB>2</SUB> nanostructure and report a reversible and stable route to achieve enhanced lithium storage capacity in anatase TiO<SUB>2</SUB>. We designed hollow anatase TiO<SUB>2</SUB> nanostructures composed of interconnected ∼5 nm sized nanocrystals, which can individually reach the theoretical lithium storage limit and maintain a stable capacity during prolonged cycling (i.e., 330 mAh g<SUP>-1</SUP> for the initial cycle and 228 mAh g<SUP>-1</SUP> for the 100th cycle, at 0.1 A g<SUP>-1</SUP>). In situ characterization by X-ray diffraction and X-ray absorption spectroscopy shows that enhanced lithium storage into the anatase TiO<SUB>2</SUB> nanocrystal results from the insertion reaction, which expands the crystal lattice during the sequential phase transition (anatase TiO<SUB>2</SUB> → Li<SUB>0.55</SUB>TiO<SUB>2</SUB> → LiTiO<SUB>2</SUB>). In addition to the pseudocapacitive charge storage of nanostructures, our approach extends the utilization of nanostructured TiO<SUB>2</SUB> for significantly stabilizing excess lithium storage in crystal structures for long-term cycling, which can be readily applied to other lithium storage materials.</P> [FIG OMISSION]</BR>

건일로딘 정(미결정에토돌락 200 ㎎)에 대한 에토돌 정의 생물학적동등성

이정애,이윤영,조태섭,박영준,문병석,김호현,이예리,이희주,이경률 한국약제학회 2004 Journal of Pharmaceutical Investigation Vol.34 No.4

A bioequivalence of Etodol™ tablets (Yuhan corporation) and Kuhnillodine™ tablets (Kuhnil Pharm, Co., Ltd.) was evaluated according to the guideline of Korea Food and Drug Administration (KFDA). Single 200 ㎎ dose of etodolac of each medicine was administered orally to 24 healthy male volunteers. This study was performed in a 2×2 cross-over design. Concentrations of etodolac in human plasma were monitored by a high-performance liquid chromatography. AUCt (the area under the plasma concentration-time curve from time zero to 24 hr) was calculated by the linear trapezoidal rule method. C_(max) (maximum plasma drug concentration) and T_(max) (time to reach C_(max)) were compiled from the plasma concentration-time data. Analysis of variance was performed using logarithmically transformed AUCt and C_(max). No significant sequence effect was found for all of the bioavailability parameters. The 90% confidence intervals of the AUCt ratio and the C_(max) ratio for Etodol™/Kuhnillodine™ were 1.01 - 1.10 and 0.87 - 1.06, respectively. This study demonstrated a bioequivalence of Etodol™ and Kuhnillodine™ with respect to the rate and extent of absorption.

Domain Name System에서 Packet Filtering을 이용한 침입탐지 및 추적

이병용(Byoung-Yong Lee),이요섭(Yo Seob Lee),전문석(Moon-Seog Jun),이철희(Chul-Hee Lee) 한국정보과학회 1997 한국정보과학회 학술발표논문집 Vol.24 No.2Ⅲ

최근에 네트워크 통신망의 확장으로 인한 역기능으로서 침입사례가 큰 문제점으로 지적되고 있다. Domain Name System은 전세계의 host정보를 가지고 있는 분산시스템이다. 특히 이러한 Domain Name System를 이용해서 Trusted host의 주소로 가장을 해서 쉽게 침입할 수 있다. 본 논문에서는 이러한 주소기반으로한 시스템의 약점을 이용해서 침입할 수 있는 몇가지 사례를 소개했다. 이러한 약점을 이용한 침입을 최소로 하기 위해서 기존의 resolver부분에 Packet filtering기능과 외부의 Name Server의 주소를 기억해서 추적할 수 있는 기능을 삽입시켰다.

뇌졸중 장애인의 경제적 스트레스 관련 요인 연구

이동걸(Lee, Dong-Geol),이무식(Lee, Moo-Sik),신원섭(Shin, Won-Seob),이병권(Lee, Byoung-Kwon),이동엽(Lee, Dong-Yeop) 한국산학기술학회 2010 한국산학기술학회논문지 Vol.11 No.2

본 연구는 대전 지역에 거주하는 만성 뇌졸중 환자를 대상으로 경제적 스트레스 요인과 관련된 재정적 압 박, 우울, 삶의 질과의 관계를 알아보고자 하였다. 연구 대상자는 대전시 소재 종합병원 및 병원에서 물리치료를 받고 있는 만성 뇌졸중환자 209명을 대상으로 하였다. 연구는 설문지를 통해 1:1 면접 조사하여 자료를 수집하였다. 수집 된 자료를 통해 뇌졸중 환자의 일반적 특성, 물리치료, 질병관련 특성에 따른 환자의 경제적 스트레스, 우울, 생활수 준, 삶의 질과의 차이를 알아보았다. 연구 결과는 생활수준(p<.000), 재정적 압박(p<.000), 우울(p<.05), 삶의 질(p>.05) 이 통계적으로 유의한 것으로 나타났다. 생활수준이 매우 심각하거나, 재정적 압박, 우울 지수가 높으며 삶의 질 지수 가 낮을수록 더 유의하게 경제적 스트레스 점수가 높게 나왔다. 후속연구에서는 환자와 직접적인 연관이 있는 보호자 와 환자의 공통된 경제적 부담 수준을 측정하여 객관적인 경제적 스트레스 지표를 고안한다면 임상적으로 중요한 자 료가 될 것이다. 또한 뇌졸중 환자의 경제적 스트레스의 감소 및 삶의 질 수준을 증진시킬 수 있는 치료적 중재의 개 발이 절실히 요구된다. This study was carried out to examine relationships between financial pressures, depression, the quality of life related with economic stress factors on patients suffering from chronic strokes residing in Daejeon. 209 patients with chronic stroke being treated in genernal hospital were selected as subjects for this study. Data were collected by conducting 1:1 interviews through questionnaires. The study examined differences in patients' economic stress, depression, standard of living and the quality of lives through collected data. The results showed statistically meaningful analysis in standard of living(p<.000), economic pressure (p<.000), depression (p<.05), the quality of life (p>.05), the standard of living (p<.05). The higher the economic pressure, depression indexes or very severe the standard of living the lower the quality of life index, so the economic stress meaningfully increases. If an objective economic stress index is devised by measuring the level of economic burdens in common with guardians of patients and patients themselves, the index will become clinically important data. Furthermore, there requires the development of medical mediation that can reduce economic stress and increase the quality of life for patients suffering from strokes.