솔-젤법에 의한 Nb_2O_5-Fe_2O_3 혼합산화물의 제조 및 산 특성조사

정석조,양희정,권재범,이내우,우희철 釜慶大學校 2000 釜慶大學校 論文集 Vol.5 No.-

In this study, some of results from a study conducted on the preparation of niobium coated hematite particles to be used as a catalyst are presented.α-Fe_2O_3 (hematite) particles obtained by aging an acidic solution of ferric(Ⅲ) ions at high temperature were first prepared as core particles and synthesised by hydrolysis at high temperature with layers of amorphous niobium pentaoxide (Nb_2O_5) deposited by the hydrolysis of niobium pentachloride. The effects of varying molecular ratio of Nb/Fe (10/1, 5/1, 1/2, 1/5, 1/10) were studied. The synthesised particles were characterized for their physical and chemical properties using XRD, SEM, TPD, BET etc. The process of the surface coating showed heterocoagulation rather than surface nucleation and growth. A preliminary investigation of the acidic characterization and specific surface area of the synthesised particles showed that these particles can achieve an acidic characteristic changed and enhanced specific surface area of that of pure niobia and α-Fe_2O_3 prepared here.

수중 시체에서 내부 장기 및 대조수에 대한 규조류의 분석

조갑래,서원준,함석훈,이종석,최동호,전병원,김양정,김광훈 內務部 國立科學搜査硏究所 2002 國立 科學 搜査 硏究所 年報 Vol.34 No.-

벼 자동화 육묘시설에서 적정 파종기와 묘대기간의 선정

鄭錫祚,孫再根 慶北大學校 農業科學技術硏究所 2005 慶北大農學誌 Vol.23 No.-

The purpose of this study was carried out to determine the optimum sowing date and days after sowing (DAS) in automatic facility located at Uiseong of Gyeoungbuk province. The seedling height was rapidly increased with a delay of sowing time from April to May. The 10-day old seedlings with suitable plant height(>10cm) for machine transplanting in the facility were obtained when the seeds sowed after May 20 at Uiseong in Gyeoungbuk province. The dry weight-height ratio of 10-day old seedlings was significantly decreased when the seeds sowed after June 20, and 15-days old seedlings did after May 10. No. of panicles/hill was reduced with increasing of days after seeding. But there were no significant difference among other yield components such as no. of grains/panicle, ratio of ripened grains, and 1,000 grain weight. The highest grain yield, 748kg/10a, was attained from the 10-day old seedlings transplanted at May 27 in comparision with those of 15-day and 20-day old seedlings. The grain yield of 10-day old seedlings transplanted at June 26 was also higher than that of 15-day old seedlings.

데이타 네트워크에 있어서 경로 선택 알고리즘에 관한 연구

조정복,이재욱,임효택,고석범 東西大學校 1998 동서논문집 Vol.4 No.-

최근에 많은 기업체에서 LAN(Local Area Network)을 기반으로 하는 인터넷 환경을 구축하는 예가 종종 보고되어 지는 것을 보면 네트워크 설계분야에 많은 관심이 집중되고 있음을 알 수 있다. 본 논문에서, Star-Ring LAN상에서 HUB의 할당과 경로 선택 문제를 취급한다. Star-Ring LAN의 설계는 1)HUB들과 사용자 노드(컴퓨터)들 간의 연결, 2)HUB들 간의 경로 선택 문제로 나눌 수 있다. 여기서 제안한 수학적 모델은 HUB의 설치 비용과 각 노드에서 트래픽의 전송 지연 시간을 고려한다. 그리고 최적 해를 탐색하기 위하여 경험적 탐색방법의 하나인 유전 알고리즘(GA:Genetic Algorithm)을 설계한다. 끝으로 본 논문에서 제안된 유전 알고리즘의 성능을 검증하기 위하여 하나의 수치 예를 보인다. Recently, many people are interested in the field of network design again as we know that Intranet environment based on LAN(Local Area Network) is often implemented at many companies. In this paper, we deal with the HUB allocation and routing problem on Star-Ring LAN. The design of Star-Ring LAN is divided into two level problems: 1)connecting between HUBs and user nodes(i.e. computers), and 2) routing between HUBs. In the mathematical model which we will develope, the cost to set up HUBs, and delay time due to communication traffic at each node should be considered as the important factors. Also, we investigate GA(genetic Algorithm)as heuristic method to search the optimal solution. Lastly, we show a numerical example to demonstrate good performances of the proposed method.

자발성 뇌교출혈 환자의 예후에 관한 임상 분석

조재영,석종식,민병국,권정택,최덕영,황성남,김영백,박승원 중앙대학교 의과대학 의과학연구소 2002 中央醫大誌 Vol.27 No.1

Patients with spontaneous pontine hemorrhage very often develop setvere disturbances of consciousness,pupilary abnormalities, respiratory and motor. They have high mortality rate. Therefore, I analyzed the correlation between the Glasgow outcome scale(GOS)and clincial manifestations or computed tomographic(CT)findings in 48 patients with spontaneous pontine hemorrhage to clarify factors predicting the prognosis. I examined 48 Patients with spontaneous pontine hemorrhage; 33 males and 15 females, age 54.6±8.99(mean±S.D.;range 39 to 68)brought to our hospital between January 1995 and December 1999, retrospectively. Correlations between the clinical manifestations, CT findings and the GOS was assessed with multivariate regression analysis. The results were as follow: 1) Patients with the pontine hemorrhage were of 8.8% in those with intracerebral hemorrhage. The ratio of male and female was 33 to 15. The incidence of age is eqial to 40,50 and 60. Total mortality was 41.6%. 2) The poor prognostic factor were that; Glasgow coma scale(GCS)3∼8, irregular respiration. pupilary abnormality, quadriplegia, Brain CT typeⅠ(massive), hydrocephalus, extrapontine extension, Intraventricular hemorrhage(IVH). These clinical analysis should be useful in determining the level of care and future resuscitative efforts.

유전적 알고리즘을 이용한 근거리 통신망의 위상 설계

조정복,임효택,이재욱,고석범 東西大學校 1999 동서논문집 Vol.5 No.-

최근에 많은 기업체에서 네트워크 설계 분야에 많은 관심이 집중되고 있다. 본 논문에서 Star-Ring LAN(Local Area Network)상에서 허브(HUB)의 할당과 경로 선택 문제를 취급한다. Star-Ring LAN의 설계는 1)허브들과 사용자 노드 즉, 컴퓨터들간의 연결,2)허브들간의 경로 선택 문제로 나눌 수 있다. 여기서 제안한 수학적 모델은 허브의 설치 비용과 각 노드에서 트래픽의 전송 지연 시간을 고려한다. 그리고, 최적 해를 탐색하기 위하여 경험적 탐색 방법의 하나인 유전 알고리즘(GA:Genetic Algorithm)을 설계한다. 끝으로 본 논문에서 제안된 유전 알고리즘의 성능을 검증하기 위하여 하나의 수치 예를 보인다. Recently, many people are interested in the field of network design again as we know that Intranet environment based on LAN(Local Area Network) is often implemented at many companies. In this paper, we deal with HUB allocation and routing problem on Star-Ring LAN. The design of Star-Ring LAN is divided into two level problems; 1) connecting between HUBs and user nodes(i.e,computers), and 2) routing between HUBs, and delay time due to communication traffic at each node should be considered as the important factors. Also, we investigate GA(genetic Algorithm) as heuristic method to search the optimal solution. Lastly we suow a numerical example to demonstrate good performances of tje proposed method.

측정값의 상황 의존성

김명석,최상돈,조상규,김정호,전헌무,김호일 慶北大學校 師範大學 科學敎育硏究所 1998 科學敎育硏究誌 Vol.22 No.-

We review the contextuality of measured values in quantum mechanics from point of view of a conventional interpretation of quantum mechanics. We will, in particular, concentrate on Bell-KS theorem which, seemingly, disproved the existence of a hidden-variable interpretation of quantum mechanics. We introduce ways to accommodate the contextuality so that Bell-Ks theorem no longer holds and therefore the existence of a hidden-variable interpretation becomes possible.

정상 관동맥을 가진 심장 점액종 환자에서 발생한 급성 심근 경색증 1예

이정민,이현승,전은정,윤호중,정욱성,오용석,김철민,김재형,최규보,홍순조,이교영,심상인 대한순환기학회 1998 Korean Circulation Journal Vol.28 No.9

효소 전처리 BCTMP 시트의 노화 거동

양봉숙,김형진,강규영,조병묵,오정수 동국대학교 생명자원과학대학 연습림 2000 연습림논문집 Vol.- No.6

It was generally known that the aging treatment of paper is accompanied with the reductions in physical and optical properties of individual fibers and sheet. In particular, the paper prepared with mechanical pulps occurs the yellowing of sheet, during aging, due to the absorption of light or temperature, and finally has limitation in widely applicable functions of paper. The aging behaviors of paper can be discussed with three groups of factor. One is considered to external factors, like heat, light and moisture. Another is commented with environmental factors, like oxygen, nitrogen, sulfur, and other air pollutant materials. The other is explained by internal factors, like pulp types, lignin contents, and so on. In this paper, the aging behaviors of paper prepared with BCTMP were studied in order to know how to affect in physical and optical properties of paper. For modification of fibers properties, a commercial enzyme was pretreated in the slurry of BCTMP, before handsheet-making. Sheets were aged by accelerated heat treatment. The comparisons were carried out in mechanical strength properties and color reversions. Aging treatments were resulted in higher brightness reductions, in enzyme pretreated paper.

이동 열원을 고려한 전자빔 용접의 유한요소해석

조해용,정석영,김명한,조창용,이제훈,서정 한국레이저가공학회 2001 한국레이저가공학회지 Vol.4 No.1

Simulation on the electron beam welding of Al 2219 alloy was carried out by using commercial FEM code MARC, which encounters moving heat sources. Due to axisymmetry of geometry, a half of the cylinder was simulated. A coupled thermo-mechanical analysis was carried out and subroutine for heat flux was substituted in the program. The material properties such as specific heat, heat transfer coefficient and thermal expansion coefficient were given as a function of temperature and the latent heat associated with a given temperature range is considered. As a result, the proper beam power is 60kVX60mA and welding speed is 1~1.5 m/min. The residual stress in the heat-affected zone as well as the fusion zone does not increase. It is necessary to use jigs for preventing distortion of cylinder and improving weld quality.