적외선 흡수 분광법 및 DPC를 이용한 치과용 수복재의 광중합 거동 분석

정찬문,김중곤,최준호,장두옥,김경남,김광만 대한치과기재학회 1998 대한치과재료학회지 Vol.25 No.1

Mechanical properties of compomers would be obtained mainly by photopolymerization by visible light irradiation. Photopolymerization behavior of two commercial compomers was investigated by FT-IR spectral analysis and differential photocalorimetry(DPC). The results obtained were as follows: 1. From FT-IR analysis, it was found that the compomer products were photocured mainly by radical polymerizations of multifunctional methacrylate monomers. Final conversion values of the polymerizations after exposure to visible light for 60 sec were 67% for Dyract and 59% for Compoglass. 2. Upon exposure the compomers exhibited autoacceleration and autodeceleration, which are usually observed in bulk polymerizations of multifunctional monomers. 3. Dyract showed higher rate of polymerization and conversion of double bond than Compoglass.

수종 복합레진 내의 bis-GMA와 TEGDMA의 구성비가 레진 인레이 법에 의한 부가적 열처리식 복합레진의 표면 및 내부의 중합률 변화에 미치는 영향

정찬문,박성호 大韓齒科保存學會 1996 Restorative Dentistry & Endodontics Vol.21 No.2

디젤 기관 대차 용접부의 내구성 평가에 관한 연구

정진성,이찬우,김호경 서울産業大學校 1999 논문집 Vol.50 No.2

The bogie frames mainly fabricate 9㎜ thick rolled steels and sometimes fatigue cracks occur in their welded joints due to inadequate fatigue design and poor weld quality. The objective of this study is to present the systematic procedure of the fatigue durability estimation and the remaining life prediction for diesel locomotive bogie frame weldments. In order for prediction of remaining fatigue lifetime, service stresses were measured at critical points, using strain gages, during field tests under several rail-roading conditions. It was found that the systematic procedure presented in this study could be applied practically to the fatigue analysis for the locomotive bogie frame weldments.

腹內側 및 背外側 腦 中隔損傷 흰쥐의 兩方回避學習 行動

鄭奉敎,任昊燦,張鉉甲 嶺南大學校附設 基礎科學硏究所 1985 基礎科學硏究 Vol.5 No.-

수술통제군과 복내측 중격 손상군 및 배외측 중격 손상군의 흰쥐들에게 양방 왕복회피상자를 사용하여 5회기의 조건회피학습을 시켰다. 이 회기는 40시행으로 이루어 졌으며 24시간 간격을 두고 실시되었다. 중격 손상이 조건회피반응(CAR)의 학습을 촉진시켰다. 그러나 복내측 손상군과 배외측 손상군 사이에는 의의있는 차이가 없었다. 두개의 학습 지표 즉 회기내 향상지표(W)와 회기간 향상지표(I)들은 회피성적과 의의있는 관계성을 보이지 못했다. 운동활동 측정에서는 중격손상흰쥐들이 5회의 조건 형성회기중 시행간에 양쪽 회피상자를 왕복한 회수가 통제군동물들보다 의의있게 높았다. 이 결과는 중격 손상이 조건회피반응 학습과 전기충격후의 운동활동에 촉진적인 영향을 미쳤음을 의미한다. 따라서 중격 손상 흰쥐들이 조건회피학습에서 향상을 보인다는 사실을 설명하는데 있어서 행동동결가설의 타당성을 지지해 준다. Rats of sham operated, ventromedial and dosolateral septal lesions groups were submitted to 5 conditioning sessions in a two-way shuttle box. The sessions were separated by a 24hr-interval. Septal lesion significantly facilitated CAR acquisition, but there was no significant difference between the two septal lesion groups. The within-session progression index(W) and inter-session progression index(Ⅰ) were not correlated with avoidance performance. Two groups of ablated animals showed significantly higher number of intertrial crossings during the 5 conditioning sessions than the sham-operated animals. It was concluded that septal lesion exerts facilitatory influence upon CAR acquisition and motor activity following electric shock. These results support the "freezing hypothesis" in the explanation of the enhanced active-avoidance performance of the rats with septal lesions.

신규호텔사업의 타당성 분석에 관한 연구

정찬종,강인호 啓明專門大學 産業開發硏究所 2000 啓明硏究論叢 Vol.18 No.1

본 연구는 호텔사업에 진출하고자 할 때 사업타당성 조사를 토대로 의사결정을 하는데 도움을 주고자 시도되었다. 경영활동 면에서 사업계획의 수행은 항상 불확실성과 변화에 따라 영향을 받게 되며, 미래에 대한 확실성이 매우 높은 경우라고 하더라도 계획된 경영은 필수적인 요건이다. 그 중에서도 신규호텔의 타당성 결정과 합리화에 관한 연구는 호텔산업의 중요한 연구대상이 되고 있다. 본 연구에서는 신규호텔사업 타당성 조사와 관련된 이론들을 체계화하여 타당성 조사항목 중 ①자연환경 분석, ②접근성 분석, ③사회·경제적 환경분석, ④내·외부적 전략분석을 통해 경상북도 포항의 사례호텔에 대한 타당성 분석을 시도하였다. 본 연구는 회계원칙상 안정성과 보수성에 입각하여 종합 분석한 제반자료를 토대로 최소기준치의 낙관적이지 못한 관점에서 분석이 처리되었음에도 불구하고 영업이익이 약 25% 수준이며, 법인세차감전 이익이 1차년도에 10%, 2차년도에 12%, 3차년도 13.3%의 전망을 보여주고 있다. 이러한 연구결과는 타 온천장 리조트 호텔에 비교해서 밝은 전망을 보여주고 있는 것이다. 더욱이 개관 이후 효율적인 경영계획의 수립과 운영시에는 더욱더 높은 이익이 발생되리라 생각한다. 그러나 교통시간의 단축에 따라 리조트호텔에서도 숙박관광이 아닌 당일관광으로 변화되는 경향이어서 객실 수요에 부정적인 효과를 줄 수 있기 때문에 이에 대한 해결책으로 다양한 활동을 할 수 있는 시설개발이 요구된다. This analysis of feasibility for new hotel business attempts to guide decision making, In carrying out the business plan uncertainty and changes always affect the execution of the plan. Even though the project for the business is affirmative a plan for operation is a necessary condition. Among them studies of the feasibility analysis for new hotel business and the rationalization for the business is an important field of the study. By organizing various theories on the feasibility analysis for new hotel business, this study attempted to apply the components of feasibility analysis in natural environment, and internal and external strategies to the case hotel in Pohang area. By applying accounting principles conservatively and safely to the data, this study finds that the hotel will make a operating profit at a level of twenty five percent and the income before income-tax will reach 10% in the first year, 12% in the second, and 13.3% in the third. These findings show that Pohang hotel has a much better prospect than the other hot spring resort hotels. An efficient operation plan and a thorough execution of the plan after opening will increase the profit level. Trends for one-day trip to resorts nowadays due to convenience for transportation will reduce a demand for rooms, Construction of various facilities for other activities at the hotel is a necessary solution.

구-막대 시스템에서 CDM을 사용한 강인한 제어기 설계

이호기,박용식,정찬수 崇實大學校 1999 論文集 Vol.29 No.1

All the controller design problem for linear time invariant dynamic system boils down to proper selecting the characteristic polynomials and numerator polynomials for concerned input-output relations. The propel selection of the characteristic polynomial is not so difficult, if only stability and response are to be satisfied, but it becomes complicated when robustness issue is added. The CDM could be a solution to this problem. CDM which is developed by Lipatov's conditions for stability and Kessler's standard form is easy to process of the controller design, especially it is more useful when the specifications are the settling time, rising time and overshoot. In this paper was used CDM design a simple but robust controller of the ball and beamsystem. The ball and beam system is highly nonlinear system. And it's linear transfer function used to design the controller. But CDM proved to be a solution to design even if there are some uncertainties like this linearized ball and beam system by simulations.

신경회로망을 이용한 정현파 밴드 히스테리시스 전류 제어기

元忠淵,梁承浩,金世燦,金學成 成均館大學校 科學技術硏究所 1993 論文集 Vol.44 No.1

Current-controlled PWM inverter offers substantial advantages in improving motor system dynamics in high-performance ac drive systems under vector control. Among the various current control techniques, fixed band hysteresis current control has been widely used. A hysteresis controller employing sinusoidal bands has been reported in recent years. In this paper new current control schemes based on neural network for PWM inverter are described, Four types of controllers have been studied and their performance compared with each other. Finally, relevant simulation results are shown to prove the effectivness of the proposed current control scheme.

한약제 복용으로 인한 연중독 1례

박찬국,김용균,박상호,정춘해,조건국 조선의대 1985 The Medical Journal of Chosun University Vol.10 No.1

단지양 근위축증(Monomelic Amyorophy) 3례 : 증례 보고 Case Report

김기찬,정호중,정상욱,정흥채,조근열 고신대학교 의학부 1999 高神大學校 醫學部 論文集 Vol.14 No.1-2

Monomelic amyotrophy is a rare form of motor neuron disease which is insidious onset in the second and fourth decades, male preponderance, sporadic occurrence, wasting and weakness confined to one limb, and absence of involvement of the cranial nerves, cerebrum, brain, stem, and sensory system. Symptoms and signs often progress for several years before spontaneously arresting. Neurologic findings and electrophysiologic studies are only useful for the diagnosis of monomelic amyotrophy and other laboratory testing are frequently normal or nonspecific. We reported three cases of typical monomelic amyotrophy with review of the articles.

초퍼제어-직류전동기의 PSPICE 컴퓨터 시뮬레이션

元忠淵,梁承浩,金德憲,金世燦 成均館大學校 科學技術硏究所 1992 論文集 Vol.42 No.2

In this paper, the authors describe the equivalent circuit for a DC motor in consideration of both magnetic saturation and armature reaction phenomena. To develop DC motor model in PSPICE is to eliminate the gap between drive electronics and models of driven machine. On the basis of these results the dynamic characteristics of a MOSFET chopper controlled DC series motor are investigated by PSPICE simulation and experiment.