Cupola 용탕을 이용한 CV 주철 제조기술 개발

최광림,최양진,신봉문,강세선 한밭대학교 산업과학기술연구소 1994 논문집 Vol.2 No.-

CV cast iron products was carried out in order to cupola process. CV cast iron products by cupola processing were obtained much more than 50kg/㎣ tensile strength and the excellent structure of CV graphite cast iron and gray cast iron. Casting waster due to the depress of pouring temperature by inoculation was reduced by development (improvement) in cast processing.

테트라사이클린에 의한 HCMV에서 바이러스유전자 발현유도

최광훈,김기호,김홍진 중앙대학교 약학연구소 1998 약학 논총 Vol.12 No.-

Recombinant viruses containing the US11 gene under the control of the tet O-modified US11 promoter were isolated ; DNA blot analysis attested to the fidelity of the recombination Western blot experiment using polyclonal antisera of US11 gene product indicated that US11 gene expression of the recombinant virus was induced in the infected tTA expressing cell lines by the presence of tetracycline. This tetracycline-dependent inducible gene expression system has potential applications to study the biological roles of HCMV genes.

TetR-VP16-mediated transcription activation system에서 TetR-VR16과 TetR 이종dimer에 의한 전사활성의 영향

최광훈,김기호,김홍진 중앙대학교 약학연구소 1999 약학 논총 Vol.13 No.-

In TetR-VP16-mediated transcription activation stystem TetR-VP16 hobodimer activates the tet operator modified minimal promoter. To determine the effect of the heterodimer of TetR-VP16 on transcriptional activation from that minimal promoter cotransfection assays were performed with U373 cells. In coexpression of TetR-VP16 and TetR the expression from the minimal promoter was activated 4-12 fold higher than in expression of TetR-VP16, suggesting that the usage of the heterodimer of TetR-VP16 can improve the effecacy of TetR-VP16-mediated transcription activation system

Microwave Absorption Characteristics of U-Type Ferrite Powders According to Substitution Elements and Its Compositions

Kwang‑Pil Jeong,Su‑Won Yang,Jin‑Hyuk Choi,Jeong‑Gon Kim 대한금속·재료학회 2021 METALS AND MATERIALS International Vol.27 No.8

In this study, partially substituted U-type ferrite (Ba4MexCo2-xFe36O60, Me: Mn, Ni, Zn, x=0.5 and 1.0) powders weresynthesized by sol–gel method. The powders were analyzed for phase formation, morphology and magnetic properties byXRD, FE-SEM and VSM respectively. The synthesized ferrite powders were pressed into a series of toroidal shaped samples,in which the weight ratio of parafn to powder was 1:5. The complex scattering parameters were measured by using vectornetwork analyzer in the frequency range of 2–18 GHz and were employed in the calculation of refection loss with variousthicknesses. The minimum refection loss was observed in the substituted nickel sample as−24.4 dB (absorption rate 99.6%)with a thickness of 2.5 mm and the bandwidth was achieved 4.8 GHz (from 7.5 to 12.3 GHz) for refection loss≤ −10 dBin the substituted zinc sample.

企業到産豫測에 있어서 現金흐름 情報의 有用性에 관한 實證的 硏究

崔光鉉,姜鎭守 영남이공대학 1995 論文集 Vol.24 No.-

The debate of accrual basis and cash flow reporting is one of the most representatives in the accounting literature. In special, many empirical studies argue that cash flow information has the additional predictive ability in predicting business failure. Accordingly, this study is to test the predictive ability of business failure by cash flow information. In order to achieve the purpose, two hypotheses are tested by multiple discriminant analysis and laboratory experiment method. Sixty samples were selected in the listed firms from 1982-1990. Thirty failure companies of them were matched by thirty non-failure companies. The results of the study are as follows: 1. The model that includes a cash flow information has superior predictive ability to the model that cash flow information is excluded. 2. The combined model that includes cash flow and financial ratios has better discriminant ability than the seperate models:one using the financial ratios and one using cash flow ratios.

사이버교육의 영향요인이 학생만족도에 미치는 영향 : 학습자 및 교수와의 상호작용 효과를 중심으로 The Moderating Effects of Interaction between Student and Teacher

최광신,노진덕 한국정보전략학회 2002 한국정보전략학회지 Vol.5 No.2

The thesis examines an influencing factors such as learning, system, and administrative support variables on student's satisfaction in cyber-education. That is to study on the effectiveness of learning, system, and administrative support for cyber-education and how does student's interaction moderate influencing factors and student satisfaction. The study was carried out through literature and empirical study. The theory made previous study, based on which The hypotheses with some models were established. Questionnaire was used to verify the hypothesis. Korea Cyber-university students filled out the questionnaire. The result of hypothesis verification in this study is as follows : First, learning quality and evaluation showed a positive influence on the students' satisfaction in learning factors. And reliance of system, recognized learning media, contents showed a positive influence on the students' satisfaction in system factors. Administrative support factors showed a positive influence on the students' satisfaction. Second, the higher level of interaction between the teacher and the student is likely to convey more satisfaction. The factors examined are the learning process, the learning evaluation, the support for the academic affairs, and the variety of course etc An interesting findings emerged throughout the analysis, showed that learning factor and administrative support factor were rather acting as the moderators.

적외선 센서를 이용한 다종가스 계측기 구현

최낙진,류정호,강봉휘,이광우,이덕동 경북대학교 센서기술연구소 1997 센서技術學術大會論文集 Vol.8 No.1

The semiconductor gas sensors with a tin oxide as the raw material have been generally used to detect gases in the principle of electrical conductivity variation. However, it was difficult to design the gas detection system due to the non-selectivity, the non-stability and the influence of temperature, humidity etc. Therefore, it was proposed NDIR(non-dispersive infrared) method using pyroelectric infrared sensor to overcome the disadvantage of the semiconductor gas sensors. This method has been recently used to detect various gases in industrial parts. It has the advantages of selectivity, stability and responsibility. The gases used in this paper were CO_(2)(carbon dioxide) and HC(hydrocarbon) series. The system was designed with the Intel MCU i8097BH microprocessor. Main topics were to remove interference effect for other gases and to minimize influence for ambient circumstance by using the software and the hardware techniques.

모듈간의 유사성 분석을 통한 시스템 규모 축소 및 재사용에 대한 연구

최신형,허경욱,진광윤 三陟大學校 1999 論文集 Vol.32 No.1

소프트웨어에서 유사한 모듈의 분석으로 소프트웨어 시스템 규모를 축소하거나 재사용 여부를 판단할 수 있다. 본 논문에서는 모듈간 유사성을 나타내는 방법으로 모듈 유사성률과 복잡성을 측정하는 사이크로매틱 그래프를 이용하여 유사한 모듈들을 하나로 통합해서 새로운 모듈을 만들어서 사용하는 방안을 제시한다. 이는 시스템 규모 축소와 모듈 재사용을 위해서 유사한 모듈을 찾아내어 구조화하는데 유용하다.

고강도콘크리트에 대한 응력-변형율 곡선과 응력블럭의 제안

최광진,송재호,장일영 國立金烏工科大學校附設生産技術硏究所 1995 産業技術開發硏究 Vol.11 No.-

The object of this paper is to propose stress-strain curve and stress block for high strength concrete. Using the established experimental data that have been presented in various documents the stress-strain relationship curves of high strength(400∼700kgf/㎠) models are presented based on both methods of logarithm regression analysis and multiple regression analysis adopted in order to establish the relationships between design parameters. And area under proposed stress-strain curve is compared with trapezoidal stress block area and rectangular stress block area using Simpson's composite formula. It is shown that the stress block of trapezoid could be regarded as that of high strength concrete. Furthermore, the results of this paper is expected to be accomodated to other important design parameters of high strength concrete.

철근콘크리트 부재의 전단변형 해석에 관한 연구

최광진,장일영,권종주,송재호 金烏工科大學校 1994 論文集 Vol.15 No.-

The object of this study is to present an analytical method using superposition of displacement due to flexural crack and diagonal tension crack in reinforced concrete members. Flexural displacement caused by bending moment could be found by the double integration of curvature derived from the relationship between moment and curvature. The macro model of shear deformation from the viewpoint of diagonal tension crack occurrence and its development has been developed. The rotational angle due to diagonal tension crack could be evaluated by using strain compatibility, force equilibrium and moment equilibrium. Furthermore the bonding characteristics between concrete and steel as well as the characteristics of dowell have been taken into consideration. The theoretical values calculated using the analytical method developed in this study have been investigated in comparison with the experimental ones which were carried out earlier in order to prove it s validity. From the results it has been shown that theoretical values agree quite well with experimental ones, and it could be pointed out that presented analytical method is widely acceptable for the practical analysis of flexural displacement of reinforced concrete members.