칠복음(七福飮)이 Glucose Oxidase에 의해 손상(損傷)된 대뇌피질(大腦皮質) 신경세포(神經細胞)에 미치는 영향(影響)

최공한,박승택,류도곤,최민호,엄상섭,허진영,강성도,고정수,서의석,성은경,조남수,이춘우,황일택,선성규,류영수,Choi, Kong-Han,Park, Seung-Taeck,Ryu, Do-Gon,Choi, Min-Ho,Um, Sang-Sub,Hea, Jin-Young,Kang, Sung-Do,Go, Jeong-Soo,Sou, Eui-Suk,Sung, Yeun-Ky 대한동의생리학회 1999 동의생리학회지 Vol.14 No.2

As the average life span have been lengthened and the rate of senile population have been raised, chronic degenerative diseases incident to aging has been increased rapidly and become a social problem. With this social background, recently, the facts that oxygen radicals(OR) have toxic effects on Central Nervous System and Peripheral Nervous System and cause neuropathy such as Parkinson's Disease, Alzheimer Disease have been turned out, and accordingly lots of studies on the mechanism of the toxic effects of OR on nerves, the diseases caused by OR and the approaches to curing the diseases have been made. The purpose of this study is to examine the toxic effects caused by Glucose Oxidase(GO) and the effects of herbal extracts such as Chilbokyeum(CBY) on the treatment of the toxic effects. For this purpose, experiments with the cultured cell from the cerebrums of new born mice were done. The results of these experiments were as follows. 1. GO, a oxygen radical, decreased the survival rate of the cultured cells on NR assay and MTT assay 2. GO, a oxygen radical, increased lipid peroxidation and the amount of LDH. 3. CBY have efficacy of decreasing lipid peroxidation. 4. CBY have efficacy of decreasing the amount of LOH. From the above results, It is concluded that Chilbokyeum has marked efficacy as a treatment for the damages caused in the GO-mediated oxidative process. And Chilbokyeum is thought to have certain pharmacological effects on controlling over aging and treating Dementia. Further clinical study of this pharmacological effects of Chilbokyeum should be complemented.

석창포(石菖蒲) 전탕액(煎湯液)이 Glucose Oxidase에 의해 손상(損傷)된 대뇌피질(大腦皮質) 신경세포(神經細胞)에 미치는 영향(影響)

최공한,박승택,류도곤,최민호,허진영,강성도,고정수,양상철,성은경,조남수,이춘우,서의석,류영수,Choi, Kong-Han,Park, Seung-Taeck,Ryu, Do-Gon,Choi, Min-Ho,Hea, Jin-Young,Kang, Sung-Do,Go, Jeong-Soo,Yang, Sang-cheal,Sung, Yeun-Kyung,Cho, Nam-Su,L 대한동의생리학회 1999 동의생리학회지 Vol.14 No.2

The purpose of this study is to examine the toxic effects caused by Glucose Oxidase(GO) and the effects of herbal extracts such as Acori Rhizoma(AR) on the treatment of the toxic effects. For this purpose, experiments with the cultured cell from the cerebrums of new born mice were done. The results of these experiments were as follows. 1. GO, a oxygen radical, decreased the survival rate of the cultured cells on NR assay and MTT assay. 2. GO, a oxygen radical, decreased the amount of neurofilaments and total protein. 3. AR have efficacy of increasing the amount of neurofilament. 4. AR have efficacy of increasing the amount of total protein. From the above results, It is concluded that AR has marked efficacy as a treatment for the damages caused in the GO-mediated oxidative process. And AR is thought to have certain pharmacological effects on controlling over aging. Further clinical study of this pharmacological effects of AR should be complemented.

흰쥐 치아 재식 후 치수 치유 양상의 조직학적 관찰

고은진,정한성,김의성,정일영,이승종 大韓齒科保存學會 2010 Restorative Dentistry & Endodontics Vol.35 No.4

본 연구의 목적은 흰 쥐 (rat) 를 이용하여 미성숙 단계의 치아를 발치 후 즉시 재식 하였을 때 나타나는 치수의 치유 양상을 조직학적으로 관찰하고자 하는 것이다. 생후 4주된 암컷 Sprague-Dawley 계 흰쥐의 상악 우측 제1대 구치를 발거 후 원래의 치조골와 내로 위치시켰다. 재식 후 3일째부터 국소적으로 치수 내 염증 소견이 관찰되었으나, 치근 부위에서는 이미 치수의 재혈관화 및 치유가 진행되고 있는 소견이 관찰되었다. 재식 후 5일째 부터는 odontoblast-like cell이 관찰되기 시작하였다. 삼차 상아질의 형성은 재식 후 1주째 부터 관찰되기 시작하였으며, 2주째부터는 확실히 관찰할 수 있었다. Odontoblast-like cell 및 삼차상아질 형성은 4주째 까지도 계속 관찰되었다. 재식 후 4주째에는 bone-like tissue 및 cementum-like tissue이 형성되었음을 관찰하였다. 본 실험을 통하여 흰 쥐 치아 재식시 석회화 과정은 초기에는 삼차상아질 침착에 의해서 진행되나, 시간이 경과하면서 점차 bone-like tissue 또는 cementum-like tissue가 차지하는 비율이 증가하는 것을 관찰하였다. The objective of this study was to observe the histology of dental pulp healing after tooth replantation in rats. The maxillary right first molars of 4-week-old rat were extracted. and then the teeth were repositioned in the original socket. At 3 days after replantation. there was localized inflammatory reaction. But, pulp revasculization and healing had already begun in the root area. At 5 days after replantation. odonto blast-like cells were observed. Tertiary dentin deposition was observed beneath the pulp-dentin border from 1 week after replantation. And tertiary dentin was increased at 2 weeks after replantation. The presence of odontoblast-like cells and the formation of tertiary dentin were continued to 4 weeks after replantation. At 4 weeks after replantation. the deposition of bone-like tissues and cementum-like tissues was observed. This results show that there is a possibility of pulp healing after tooth replantation in rats and the mineralization of tooth can progress. The mineralization of tooth after replantation was initially occurred by the deposition of tertiary dentin. but as time passed. the deposition of bone-like tissues and cementum-like tissues was begun and increased.

전원의 간섭잡음 억제를 위한 적응잡음 제거기법

최한고 國立金烏工科大學校附設生産技術硏究所 1993 産業技術開發硏究 Vol.9 No.-

Spectrum and timing analysis of biomedical signals have been used as effective diagnosis or remedy tools for pathological diseases. The most common problem in bioelectric recordings is the presence of interferences from electrical power sources, i.e., 60[Hz] and its harmonics. Reduction of these interferences from the recorded signals is essential to detect a particular activity of the signal or to reduce the effect of spectral overlap of both the signals. This paper describes the cancellation of the electrical interferences from respiratory electromyographic (EMG) activity using an adaptive noise calceler and some features in processing this technique. The adaptive noise calcellation technique was found to successfully reduce the interferences.

광대역 잡음제거를 위한 신경망 적응잡음제거기 설계

최한고,이상재,채창현 金烏工科大學校 産業技術開發硏究院 1999 産業技術開發硏究 Vol.15 No.-

This paper describes a nonlinear adaptive noise canceller(ANC) using neural networks as the nonlinear adaptive filter to make up for drawback of the conventional noise canceler with the linear adaptive filter. Performance of the proposed noise canceller is evaluated using both periodic and nonstationary signals contaminated with broadband noise, assuming that the noise of primary and reference inputs is uncorrelated. The proposed ANC is compared with the adaptive noise canceller of the linearfilter for the relative comparison of noise rejection performance. Experimental results show that the neural network based ANC outperforms the linear ANC with respect to mean square error, and the recurrent neural network adaptive filter performs the best. It is verified that the neural network adaptive filter, having highly nonlinear dynamics by virtue of the distributed nonlinearities, can be used as an effective adaptive filter for the rejection of broadband noise.

뇌파신호 디스플레이를 위한 데시메이션 기법들의 비교연구

최한고 國立金烏工科大學校附設生産技術硏究所 1994 産業技術開發硏究 Vol.10 No.-

The display of biological signals in raster scan monitors often involves a multirate sampling operation which consists of decimation and interpolation. All digitized electroencephalographic(EEG) samples cannot be displayed due to predefined formats. For instance, the EEG signal of 10 to 30 seconds(2,500 to 7,500 samples at 250[Hz] sampling frequency) must be displayed in the computer screen to keep the aspect ratio of the paper polygraph output. Since the current affordable display technology plots at most 2,000 pixels per row, some signal samples need to be discarded. This paper studies methods to perform this operation characterizing them from the signal processing view-point and compares the display quality among several decimations.

GTO 게이트 드라이버를 위한 2차측 제어 ZVS-PWM 컨버터

김학성,최한고,이상재 金烏工科大學校 1994 論文集 Vol.15 No.-

전원장치의 입출력간의 전기적 절연은 전력 트랜지스포모로 제어신호는 보통 optocoupler를 이용한다. 그러나 고압절연(>10KV)인 경우는 제어신호의 절연은 트랜스포머나 광케이블을 이용하게 되는데 이들은 직류신호를 직접 전송할 수 없으므로, 출력전압을 주파수로 변환하여 전달하게 되므로 변환시간 만큼의 시간지연이 생기게되어 전원장치의 응답특성과 제어성이 나빠지게 된다. 본 논문에서는 ZVS-PWM컨버터를 고전압 절연이 요구되는 GTO 게이트 드라이브의 전원데 적용하여 온라인으로 제어하는 것과 같이 빠른 응답특성과 안전성 및 제어성을 얻기위한 2차측 제어회로를 제안하여 그 유용성을 시뮬레이션을 통하여 확인하였다.

병렬 기구 공작 기계의 머신 시뮬레이션에 관한 연구

김기욱,정윤교,고해주,신혁,유한식 한국공작기계학회 2006 한국공작기계학회 추계학술대회논문집 Vol.2006 No.-

Recently, parallel kinematic machine tool with high accuracy and stiffness is causing great concern in 5-Axis processing which is applied in manufacturing with complicated shape products. However, there are some inherent difficulties in parallel kinematic machine tool such as a collision between workpiece and tool, over-cut and under-cut, verification of tool path route in progress. To solve these problem in advance, it needs machine simulation of parallel kinematic machine tool above all things. the purpose of this study is, therefore, carried out machine simulation for parallel kinematic machine tool and accumulation of technical knowledge for the productivity and efficiency in parallel kinematic machine tool through verification of 5-Axis machining.

신경망을 이용한 적응잡음제거기 설계

곽우혁,최한고,박원우 金烏工科大學校 1998 論文集 Vol.19 No.-

This paper describes a nonlinear adaptive noise canceller using neural networks as the nonlinear adaptive filter, which is suitable for extracting periodic signals and nonstationary signals contaminated with broadband noise. Two neural networks. feedforward (FNN) and recurrent neural networks (RNN), are used as nonlinear adaptive filters. In this paper, it assumes that the noise of the primary input in the adaptive noise canceller is not the same characteristic as that of the reference input. Performance of the proposed noise canceller is evaluated using peripdic sawtooth signal and speech signal with white noise, and than compared with conventional adaptive noise canceller of linear structure. Experimental results show that the neural network based noise canceller outperforms the linear noise canceller. It is also verified that the RNN adaptive filer performs best with respect to noise rejection of mean square error.

초등학교 과학교실 및 과학동아리 관련 현장 조사 및 프로그램 개발 모형 설정

임청환,김남일,권성기,고한중,이성호 한국과학교육학회 2005 한국과학교육학회지 Vol.25 No.2

본 연구의 목적은 과학 교실 및 과학반, 과학동아리 활동과 관련하여 일선 학교 현장에서는 어떤 문제점을 갖고 있으며 어떤 요구가 있는지 조사연구를 통해 알아보고 그 결과를 바탕으로 활동 프로그램을 개발하기 위한 개발 모형을 제시하는 것이었다. 146개 초등학교의 과학 관련 교사를 대상으로 설문 조사하였으며 조사결과, 교사들은 다양한 문제점과 해결 덜'간을 제시하였는데 다음과 같은 시사점을 얻을 수 있었다. 첫째, 다양한 과학 활동에 대한 행·재정적 지원이 절실히 필요하다. 둘째, 과학비전공 교사도 쉽게 다룰 수 있는 활동 프로그램의 제공이 필요하다. 셋째, 재미있는 활동으로 구성된 프로그램이 있어야 한다. 넷째, 프로그램은 준비가 용이한 활동으로 이루어져야 한다. 다섯째, 탐구 활동 중심의 평가 방법이 제시되어야 한다. 이러한 조사 결과를 바탕으로, 교사, 학생, 운영 환경을 축으로 하는 프로그램 개발 맥락을 설정하고 주제 설정, 활동구성, 차시구성, 활동지 구성, 교사용 지침서 구성의 단계로 이루어진 개발 모형을 제안하였다. The purpose of this study was to investigate the needs of elementary school teachers on extra-science programs and to suggest development model for extra-science program. Survey research was conducted on 146 science-related teachers all over the country. As the result, teachers presented several problems and solutions on extra-science activities and programs. The suggestions from the results are as follows. First, more administrative and financial supports are required. Second, it must be the programs with which any teachers, regardless of their major fields, can execute easily. Third, the programs should be interesting for students to do. Fourth, it should be easy to prepare activities and materials, Finally, the inquiry-focused assessment method should be presented in each program. Based on these suggestions, the context of development of programs was established. Three axises of, students, teachers, and environment, were included in the context. The model of development of programs was set up based on the context. It was constructed with six process steps, Confirmation of theme, Composition of work frame, Organization of each period, Worksheets for students, Guidebook for teachers, Completion, and one or two assessment criteria in each process steps. It must be useful to development of extra-science programs that is appropriate to the need of teachers.