6-hydmxydopamine 파킨슨병 모델에서 Apomorphine의 투여에 따른 회전운동 변화의 시간적 추이

홍근식,김병곤,전범석,윤병우,이광우,노재규,이상복,명호진 대한신경과학회 1999 대한신경과학회지 Vol.17 No.1

콘크리트 슬래브의 진동제어에 관한 연구

변근주,방춘석,노병철 연세대학교 산업기술연구소 1993 논문집 Vol.25 No.2

In recent years, the design criteria for vibration control are more strict. In this study, the dynamic characteristics of the slab is analyzed and the vibration is controlled for the special peculiarity of structures. First, the procedure of dynamic analysis is developed by the finite element method and then examined by using the slab model tests. Second, in order to improve the dynamic characteristics, the effects of the number of supports, material properties, position of exciting force, added mass and dynamic balance on the dynamic behavior of concrete slabs are analyzed. It is concluded that the vibration can be controlled by the change in the natural frequency of system and the use of the high-strength concrete or polymer impregnated concrete(PIC), and the dynamic characteristics can considerably affected by the arrangement of equipments, and added mass. etc.

생약추출물이 초기우식법랑질의 재광화에 미치는 효과

홍석진,손재범,박근형 대한구강보건학회 2003 大韓口腔保健學會誌 Vol.27 No.2

Since plant extracts have shown antibacterial activities, we hypothesized that herbal plant extracts would further increase cariostatic efficacies of the fluoride dentifrices.OBJECTIVE: The purposes of this study were to determine the minimum inhibitory concentration(MIC) of 9 different Korean herbal plants extracts on the S.sobrinus KCTC3308 and the efficacy of NaF-Silica dentifrices with or without the extracts. METHODS; The MIC of the methanol-extracts on the growth of S.sobrinus was determined. Subsurface caries lesions were prepared as previously described (Hong et al.J Dent Res. 77:843, 1998). After Vickers hardness number(VHN) were determined, the specimens were assigned to 9 test groups of 12 each by randornized blocks with VHN stratification. The specimens were tested for remineralization In vitro subsurface enamel lesion under cyclic microbial dynamic condition simulating in vivo carious fomation. The statistical significance of delta VHNs was determined by Students t-test and one-way ANOVA. RESULTS: The MIC of the Angelica gigas extract was 3 ㎎/㎖, as same as Akebia quinata and Camellia sinensis was 4 ㎎/㎖. However, all 9 extracts tested in the study demonstrated the synergistic cariostatic potential with known fluoride dentifrices. CONCLUSION: The NaF-herbal extract in silica base dentifrice significantly increased the cariostatic effect of NaF-Silica base dentifrice.

두부손상 환자의 정신과적 합병증에 관한 장애 감정례의 일반 사항에 관한 분석

신석철,왕성근,신윤오,김덕호,김상국,강동숙 충남대학교 의과대학 지역사회의학연구소 1991 충남의대잡지 Vol.18 No.2

Authorst ried retrospective analysis to find out general characteristics of the patients undergoing disability evaluation at the department of psychiatry Chungnam National University Hospital from 1986 to 1990. The subjects, who were suffered from psychiatric complications due to head trauma by traffic accident, were 66 patients and they were classified depending on the demographic status, situations of traffic accident, evalaution periods, whether or not perform operation, and rates of evaluated disability and diagnosis. The results were summarized as follows. 1. General background of the subjects were as follows. 1) The frequency order of request were court(59 %) and insurance company(19.7%). 2) The place of accident was more common in large city, common accident vehicle were bus, truck, and cabs. 3) The season of accident were more common in Spring and Autumn. 2. Male(71.2%) was more common than in female and more common in the age group of 5-19 years old(37.9%). The most frequent job of the patients was labour, and the education level was more common in the graduates of elementary school(47.9% ). 3. The interval between accident and evaluation was most frequent in 12-23 months(47.5%), and duration of evaluation was mostly 14 to 21 days. Performed brain operation was 31.8% and non-operated patients was 50.0%. The rates of disability according to the McBride's disability evaluation were mostly belonged to the group of beow 40%(74.1%). 4. The final diagnosis after evaluation were organic personality disorder(45.5%) and dementia(31.8%).

Al₂O₃섬유강화-알루미늄 금속 복합 재료에 첨가된 Li의 영향

金錫胤,金政根 弘益大學校 1989 弘大論叢 Vol.21 No.2

Samples of FP(Al₂O₃) fiber/Al-2.5Li metal matrix composite have been fabricated by Liquid metal pressure forming technique. The fiber orientation in the composite was unidirectional to the specimen axis. The ?? of the specimen was 468 MPa and especially young's modulus was very high enough to 150.9GPa owing to the good bonding between fiber and matrix. The fracture surfaces exhibited that the cracks were propagated in a mixed mode, that is, fibers bread with the matrix, debonding and pullout from the matrix until a final fracture took place. The interfacial delaminated dendritic structure were also observed. Li addition increased the wettability of the fiber in the matrix, because of the formation of two compounds in the interfaces, namely, α-LiAlO₂and LiAl??O??.

灌漑用 小溜池의 內容積에 關한 硏究

宋錫銀,周栽洪,李裕根 진주산업대학교 1982 論文集 Vol.20 No.-

Obtained results for study as above are as follows. 1. The unit depth of water of the present state of reservoirs was below 160 millimeter on the average. 2. The frequency of drought happened one time per three years. 3. The ratio of a well irrigated paddy field was less than 40%. 4. When the unit depth of water of reservoirs is at least 300 millimeter, it is regarded as a well irrigated paddy field. 5. If possible technically, when we raise the present state of dam height of reservoirs more than 1 meter, we can store up the irrigation water for somehow 20 days.

생애주기비용과 계층적분석과정 기반의 최적 교량대안 선정

장미숙,정근채 충북대학교 건설기술연구소 2004 建設技術論文集 Vol.23 No.1

The value of a structural system is dependent on the performance and the cost. To increase the value of a structural system, we should increase the performance and decrease the cost at the same time. When selecting an adequate alternative among various candidates, we should consider criteria both in performance and cost. In this paper, we propose an Analytic Hierarchy Process based methodology for selecting the optimal bridge alternative among various candidate bridges, which consider multiple evaluation criteria simultaneously. The proposed selection methodology can give the optimal alternative by using not only general qualitative criteria such as sociality, shape and constructibility, but also quantitative criteria such as life cycle cost, structural stability, usability, and environment. However, the proposed methodology is difficult to use manually since it requires much information and complex analysis models. To overcome the lack of practical usability, we also propose a framework for a decision support system which can help the decision maker by using information technology. We expect that the proposed selection method and the decision support system framework can be used as a useful tool for initial planning of structural systems, especially bridges.

현대식 회전교차로의 용량분석과 기하구조 설계에 관한 연구

김석근,이용재 중앙대학교 건설환경연구소 2001 環境科學硏究 Vol.12 No.2

본 연구는 우리 나라에는 아직 소개된 바가 없는 현대식 회전교차로의 용량분석을 실시하는 경우 활용될 수 있는 새로운 형태의 용량 모형식의 도출에 관한 것이다. 현재 세계 각국에서 사용하고 있는 회전교차로의 용량 관련식들은 경험식 모형과 이론식 모형으로 대별된다. 본 연구에서 제시되는 용량 모형식은 2000년 미국 도로용량편람(HCM)에서 제시하고 있는 간격수락이론에 의한 이론식 용량 모형식의 기본구조는 그대로 수용하지만, 모형식의 유도과정에서 가정된 비현실적인 요소인 차량/운전자의 임계간격과 추종시간의 일관성과 동질성의 문제를 해결할 수 있는 동등한 용량 보정계수들과 교차로의 기하구조 특히 경사도에 대한 보정계수를 각각 도출하여 기본 모형식에 활용하도록 하는 확장된 용량 모형식이다. 또한 교차로의 운영분석과 설계 때에 필연적으로 요구되는 회전교차로의 설계요소에 대한 용량변화를 도표로 작성하여 실무에 참조할 수 있도록 제시하였다. This article is concerned with the development of a capacity formula that can be applied to modern roundabouts, which have not yet been introduced in Korea. There are two main model approaches that estimate the capacity at modern roundabouts throughout the world, namely, empirical statistical models and theoretical models. The formula in this paper adopts the basic structure of the 2000 HCM model, a notable theoretical model initially developed by gap acceptance theory. However, the formula proffered in this paper takes into account equivalent adjustment factors for consistency and homogeneity assumptions made in the original formula. In addition, another adjustment factor for approach grades at roundabouts is also introduced. Thus, the HCM formula is gradually enhanced with the adjustment factors developed in this paper, Some of the computational results are also graphically illustrated for the benefit of practitioners.

生産의 國際的 關係와 國際分業 : 世界經濟의 「構造變化」와 관련하여

朴奭根 인제대학교 1993 仁濟論叢 Vol.9 No.2

This study attempts to analyze the way in which emerging technological innovation influences the world economy. To do this, it first presents a long-term view of the interrelationship between the global productive forces and global relations of production. It then outlines in the context of the global capitalism the main charateristic of the scientific and technological revolution which is based on resent microelectronic innovation. It finally recognizes that the characteristics will offer a new range of opportunities for restructuring the world economy.

數種의 市販 淸凉飮料에 依한 琺瑯質 脫灰效果

김영숙,신영림,송근배,김영진 慶北大學校 齒科大學 1992 慶北齒大論文集 Vol.9 No.1

The purpose of this study was to investigate the effects of tooth enamel dissolution by commercial beverages. Five kinds of beverages(cola, cider, aquarius, boribori and sunkist orange) were selected for test medium and sixteen of extracted 3rd molar were used for tooth enamel specimens. The acidity of each beverage was determined with pH meter and the concentration of total glucose was checked with Glucose kit and U-V spectrophotometer. The dissolved calcium was determined by Atomic Absoprtion Spectrophotometer and the change of enamel surfaces were observed with Scanning Electron Microscopy(× 400 & × 1,000 magnification). All collected data were analyzed by one-way & two-way ANOVA in SPSS/PC^+ program. The obtained results were as follows: 1. The major containing acid type of cola beverage was phosphoric acid but the other beverages(cider, aquarius, boribori and sunkist) were citric acid. The pH of each beverage was lowest in cola and sport drink, cider, boribori, fruit juice in ascending order(F=205.85, p<0.001), the average pH of 5 kinds of beverage was 2.84 ±0.04, all beverages used in this experiment were low enough to decalcify the tooth enamel. The total glucose concentration of each beverage was 2.74% in aquarius, 2.78% in cider, 3.96% in sunkist, 4.23% in boribori and 4.27% in cola. 2. The average dissolved calcium concentration in 5cc of beverage was 1.54±0.12ppm/5㎖ of HNO_3 in cola, 1.76±0.38ppm in sunkist, 1.90±0.09ppm in boribori, 3.03±0.09ppm in aquarius, 3.59±0.38ppm in cider and the final calcium contents, which is extrated original calcium contents from total calcium contents after 120 minutes were highest in cola(1.27ppm) and aquarius(1.02ppm), cider(0.58ppm), sunkist(0.45ppm), boribori(0.33ppm) in the order(p<0.05). 3. The direct proportional relationship was not found between the degree of surface change on Scanning Electron Microscopy and the amount of dissolved calcium per immersion time. But the more the immerging time was lengthened, the more surface change was observed. The surface change of 120 minutes group was more remarkable than 30 and 60 minutes immerged group in each beverage.