흰쥐에서 말초신경 손상후 뒤뿌리신경절세포의 신경영양인자와 그 수용체의 발현 양상

백선용,양만석,문총석,김봉선,김재봉,김진정 대한해부학회 1999 Anatomy & Cell Biology Vol.32 No.2

나노결정 실리콘의 전기적 특성에 관한 연구

정서용,최석호 慶熙大學校 레이저 工學硏究所 1997 레이저공학 Vol.8 No.-

DC conductivity measured for nanocrystalline Si(nc-Si) deposited by remote plasma chemical vapor deposition(RPCBD) exhibited the Meyer-Neldel rule(MNR). Basic experimental results indicate that the electrical and optical properties of the RPCVD nc-Si films do not follow the quantum size effects, but strongly depend on the sample preparation conditions, largely on the substrate temperature. We found that the MNR parameters, almost independent of the bias voltage 2.4x10??(ohm . cm)??, 55 meV at a bias of 10V. In samples soaked by a white light of 100 mW/㎠ for one hour, the slope of the MNR increased by 4.6 eV??. The quantitative resemblance of the MNR to the one found in hydrogenated amorphous silicon(a-Si:H)indicated that the conduction in nc-Si films takes place in a a-Si:H-like tissue that wraps the luminescent crystallites.

정보통신분야 국가기술자격증 취득과 정보통신공학 전공 학생들의 취업률 증진을 위한 방안

정기석,민경일,조용석,신용달 永同大學校 1997 硏究論叢 Vol.3 No.1

본 연구에서는 정보통신분야 국가기술 자격증 취득과 정보통신전공학생들의 취업률증진을 위한 방안을 제시하고 그 결과를 고찰하였다. 국가기술자격증 취득방안으로는 동기부여, 특강별로 한 과목씩 단계적인 강의 등의 방법을 제시하였고, 취업률 증진 방안으로는 학생수준에 맞는 업체선정지고, 취업자료 수집, 업체방문 등의 방법을 제시하였다. 연구결과는 업체의 요구조건은 공통적으로 어학증명서와 기술자격증으로서 대기업에 취업하기 위해서는 어학실력이 좋아야 하며 따라서 TOEIC등의 시험을 적극 권장할 필요가 있음을 보여준다. This paper examines a plan for acquiring a technical qualification and promoting the percentage of employment in Information & Communication Engineering Major. As a plan for acquiring a technical qualification, study methods of a motive allowance, step lesson of a curriculum etc. are presented. Also, as a plan for promoting the percentage of employment, study methods of a collection of employment data, company visit etc. are presented. Results of study show that companys require a technical qualification and a certificate of foreign language, so TOEIC should be recommended.

수인성 바이러스의 수계환경내 분포실태 및 검색방법론

정용석 慶熙大學校 地球環境硏究所 1998 지구환경논문집 Vol.9 No.-

RF-MOSFET의 개선된 BSIM3 소신호 모델과 측정기반 파라미터 추출

심용석,김정보,양진모 대구대학교 정보통신연구소 2004 情報通信硏究 Vol.3 No.1

RF 영역에서 동작하는 초미세 MOSFET를 위한 새로운 소신호 모델과 파라미터 추출방법을 제안하였다. 이 모델은 BSIM3v3 코어에 기판 회로망 모델과 기생소자들이 추가된 매크로 모델로 구현되었다. 모델 파라미터들은 공통-소오스로 구성된 다양한 크기와 바이어스 조건하에서 nMOS 트랜지스터의 측정된 S-파라미터로부터 직접 추출되었다. 직접 파라미터 추출은 활성영역에서 동작하는 등가회로에서 Z와 Y 파라미터를 이용하여 임베이딩 기법으로 이루어 졌다. 0.5 GHz에서 20 GHz 범위까지 측정된 S-파라미터와 소신호 모델의 시뮬레이션 결과는 우수하게 일치하였다. A new small-signal model for deep submicrometre MOSFET for radio frequency operation and its parameter extraction method are proposed. The model is implemented as macromodel with substrate network model and parasitic elements added to the BSIM3v3 core. Model parameters are directly extracted from S-parameter data measured from common-source structured and various sized and biased MOS transistors . Direct parameter extraction is performed by embedding technique using Z and Y parameter analysis on the equivalent circuit in the saturation region of operation. Excellent agreement between the simulation results of the small-signal model and measured S-parameters at virious-sized MOS transistor in the range from 0.5 GHz to 20 GHz has been obtained.

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.

降水物 tritium濃度의 年中變化

蔡貞淑,尹柱庸,田載植 충남대학교 자연과학연구소 1983 忠南科學硏究誌 Vol.10 No.1

A series of measurements of tritium concentration in precipitation has been carried out at the College of Sciences, Chungnam National University for a period of one year from March 1982 to February 1983. Samples were taken from every precipitation and processed through electrolytic enrichment for liquid scintillation counting of tritium activity. Results are summarized in a table and figure which shows a rough periodicity in the annual variation of tritium concentration with a maximum monthly mean of 1318±197 TR in April 1982 and a minimum of 220±37 TR in July of the same year.

급성심근경색증의 조기진단에 있어서 Myoglobin의 진단적 의의

이정헌,김종근,정병천,서강석,박정배,조용근,류재근,전재은,채성철,박의현 大韓應急醫學會 1999 대한응급의학회지 Vol.10 No.2

Background: Exact and early diagnosis of acute myocardial infarction (AMI) is essential for the subsequent routine management of this frequent cardiovascular disease. Currently, AMI has been diagnosed using the combination of the history, electrocardiogram(ECG), and biochemical markers of myocardial necrosis. At present, many biochemical markers are used to diagnose AMI. In this study, the predictive values of serum myoglobin and creatine kinase-MB(CK-MB) were compared in the emergency department. Methods: Fifty-four consecutive patients who presented within 12 hours from onset of chest pain of presumed cardiac origin were enrolled into the study. Patients with trauma or renal failure were excluded. The serial serum myoglobin and CK-MB levels were obtained prospectively at admission and 2, 4, 6, 12, 24 and 48 hours after admission. We compare the levels of serum myoglobin and CK-MB within 2, 4, 6, 8, 10, 12, 24, and 48 hours after symptom onset respectively. And we compare the sensitivity, specificity, positive predictive value, and negative predictive value of myoglobin and CK-MB. Results: using World Health Organization criteria, 28 AMI patients were identified. Mean time from symptom onset to presentation was 4.1±1.3 hours. The predictive values of serum myoglobin were better than those of CK-MB within 6 hours after symptom onset. But, 6 hours after symptom onset, the predictive values of CK-MB were better than those of serum myoglobin. The false positive cases of serum myoglobin were 3-one was lung cancer with pleural effusion and the others were unstable angina. The false positive cases of CK-MB were 6-one case was viral myocarditis and the ohters were unstable angina. Conclusion: To compare the serum myoglobin and CK-MB in the diagnosis of AMI, serum myoglobin had better predictive values than CK-MB within 6 hours after symptom onset and useful in the early diagnosis of AMI. But, 6 hours after symptom onset, CK-MB had better predictive values than serum myoglobin and useful in following up.

신장세포암에서 WT1과 IGF2 유전자의 발현

이정호,김응석,김용섭,장성익,윤환중 동국대학교 의학연구소 2000 東國醫學 Vol.7 No.-

IGF2 유전자는 제 11번 염색체 단완 (11p15.5)에 위치해 있으며 아버지로부터 유전된 대립형질만 기능을 하는 genomic imprinting되는 유전자이다. 이 유전자는 정상세포에서는 세포증식을 촉진시키는 작용을 하고 몇가지 암에서는 LOI에 기인한 과발현이 있는 것으로 알려져 있다. 한편 WT1 유전자는 제 11번 염색체 단완 (11p13)에 위치해 있으며 어머니로부터 유전된 대립형질만 기능을 하는 즉 IGF2 유전자와는 정반대의 genomic imprinting 되는 유전자이다. 이 유전자는 비뇨생식기관의 발생에 매우 중요한 유전자이며 암화과정에서는 암억제 유전자로서 기능한다. 소아신장에서 발생되는 Wilms 종양에서는 IGF2 유전자와 WT1 유전자의 고장이 주원인으로 생각하고 있다. 이에 근거하여 성인에서 발생되는 신장세포암에서도 Wilms 종양에서의 결과와 같을 것인지의 여부를 알기 위하여 12명의 신장세포암 환자 ( 남자 6명, 여자 6명)로부터 얻은 조직을 이용하여 이들 유전자의 발현정도를 조사하였다. 환자의 연령은 남자에서는 43세에서 56세까지였고 여자에서는 23세에서 61세까지였다. 신장세포암에서 IGF2 유전자와 WT1 유전자의 발현정도는 다같이 성별이나 연령과는 무관하였다. IGF2 유전자는 50%에서 발현되었으며, 그 발현정도는 저발현에서부터 중등도 그리고 과발현까지 다양했으며 주로 신세뇨관 부위에 있는 암세포에서 발현되었다. WT1은 56%에서 발현되었으며 과발현과 중등도 발현이 대부분이었다. IGF2 유전저의 발현과 WT1 유전자의 발현은 각 예에서 상이하게 나타나서 두 유전자간의 작용은 일치하지 않았다. IGF2 gene which was located on chromosome 11p15.5 is expressed by the paternal allele. It stimulates the cell proliferation in normal cells, however, it is over expressed in some cancers due to LOI (loss of genomic imprinting). In contrast, WT1 gene which was located on chromosome 11p13 shows maternal specific monoallelic expression. It is a very much important gene in developing urogenital system, besides, it acts as tumor suppressor gene in some cancers. IGF2 and WT1 genes are the main causative genes in Wilms tumor which is developed in pediatric kidney. To understand the status of IGF2 and WT1 expressions in renal cell carcinoma which is developed in adult life, tissues from 12 cases patients (male 6 cases ; female 6 cases) were detected by immunohistochemistry with antibodies from IGF2 and WT1 genes. To distinguish the different ages between Wilms tumor and renal cell carcinoma, the patients age in renal cell carcinoma was ranged in 43-56 years old in man and 23-61 years old in female. No direct correlation was, in general, between gene expression of IGF2 and WT1 and age or sex of patients in renal cell carcinoma. Expression of IGF2 gene revealed six of twelve (560%) and expression of WT1 gene showed seven of twelve (56%) in renal cell carcinoma, respectively. The status of IGF2 gene expression was varied from low to high expression. In contrast, the status of WT1 gene expression was higher than in IGF2 gene expression. However, there was no apparent correlation between expressions in each cases. In conclusion, IGF2 and WT1 genes are very important in carcinogenesis of renal cell carcinoma, however interaction between two genes was obscure.

레저스포츠 참여와 여가만족의 관계

김용인,정갑석,장호중,김정묵,정석현 한국스포츠리서치 2004 한국 스포츠 리서치 Vol.15 No.1

The purpose of this study was to examine the relationship between participation in leisure sport activities of leisure satisfaction. To accomplish this research purpose, there were two research questions; Firstly, Is there difference on leisure satisfaction according to the participation in leisure sport activities?, Secondly Will the degree of participation in leasure sport activities influence the leisure satisfaction? The population for this study was participants in Leisure sports activity program located in Seoul. The final 227 responses (participation 163, non-participation 114), collected by cluster random selecting method, were used in the data analysis procedure. The items for measuring leisure satisfaction were largely based on Lee(1992)s study, and the degree of participation in leisure sport activities was measured by the period and frequence of participation. To analyze the final data (277), the reliability analysis, analysis of covariance, multiple classification analysis, and multiple regression analysis were used. The conclusions for this study were as followings; Firstly, leisure satisfaction is partially different by participation yes or no of the leisure sports activity. That is, leisure satisfaction is higher participation of leisure sports activity than non-participation Secondly, leisure satisfaction is partially influence by the participation of degree of leisure sports. That is, period and frequence are influence on leisure satisfaction.