• Journal of Korean Neurosurgical Society
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• 제42권3호
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• pp.205-210
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• 2007

Objective : Hyperpolarization-activated cyclic nucleotide-gated (HCN) channels mediate the hyperpolarization-activated currents (Ih) that participate in regulating neuronal membrane potential and contribute critically to pacemaker activity, promoting synchronization of neuronal networks. However, distinct regional and cellular localization of HCN channels in the brain have not been precisely defined. Aim of this study was to verify the precise cellular location of HCN1 channels in rat cerebellum to better understand the physiological role these channels play in synaptic transmission between CNS neurons. Methods : HCN1 expression in rat brain was analyzed using immunohistochemistry and electron-microscopic observations. Postsynaptic density-95 (PSD-95), otherwise known as locating and clustering protein, was also examined to clarify its role in the subcellular location of HCN1 channels. In addition, to presume the binding of HCN1 channels with PSD-95, putative binding motifs in these channels were investigated using software-searching method. Results : HCN1 channels were locally distributed at the presynaptic terminal of basket cell and exactly corresponded with the location of PSD-95. Moreover, nine putative SH3 domain of PSD-95 binding motifs were discovered in HCN1 channels from motif analysis. Conclusion : Distinct localization of HCN1 channels in rat cerebellum is possible, especially when analyzed in conjunction with the SH3 domain of PSD-95. Considering that HCN1 channels contribute to spontaneous rhythmic action potentials, it is suggested that HCN1 channels located at the presynaptic terminal of neurons may play an important role in synaptic plasticity.

• 한국컴퓨터정보학회논문지
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• 제10권5호
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• pp.271-280
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• 2005

본 연구에서는 한방분야에서 검진에 영향을 미치는 요인들에 대하여 의사결정나무기법을 이용하여 도출하였고, 군집 분석을 통해 환자들의 특성에 대하여 알아보았다. 또한 질병간 연관성 분석을 재입원 환자 군들의 질병 구조를 파악하기 위하여 실시하였다 아울러 도출된 군집들은 병원수익에 어떤 영향을 미치고 있는지에 대한 결과를 도출하였다. 즉 한방분야에 대하여 데이터마이닝 기법을 적용한 데이터베이스 마케팅을 통해 내원 환자들의 특성을 파악하고 병원 수익에 영향을 미치는 요인들을 실증적으로 도출하였다. 본 연구를 통하여 병원의 효율적인 운영과 활성화를 위한 데이터베이스 마케팅을 실시함으로써 병원 경영 에 효율성을 도모할 수 있을 것이다.

• 대한인간공학회지
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• 제17권1호
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• pp.47-54
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• 1998

Product design and development is very important process in enterprise activities. Reducing development time and reflecting consumer's needs is required to product design and development for increasing benefit and decreasing cost. Human sensibility ergonomics is one of the important technology of R&D in product development. However, the subjective method of human sensibility ergonomics has several problems to analyze and to Quantify experimental data and objective method of human sensibility ergonomics is still in process on study. In this research, new analyzing method is proposed for the subjective human sensibility ergonomics applied with fuzzy set theory. What is the useful theory for controlling uncertain type of information like human mind? This approach is more effective method for analyzing consumer's needs for product design and development process. At collecting needs, certainty scale is added for adapting hedge of fuzzy function. Using a kind of union operator, synthesize each item to analyze identification of each item with fuzzy hamming distance. Identification of analysis is classified with the relational weight using Relationship Chart Method, and is drawn the relationship diagram for clustering each item. A case study with sample test is conducted and demonstrated with this suggested method for more effective way.

• 한국전산유체공학회지
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• 제5권2호
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• pp.55-63
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• 2000

In this paper, the numerical study has been done for the improvement of the superdetonative ram accelerator performance and for the design optimization of the system. The objective function to optimize the premixture composition is the ram tube length, required to accelerate projectile from initial velocity V/sub 0/ to target velocity V/sub e/. The premixture is composed of H₂, O₂, N₂ and the mole numbers of these species are selected as design variables. RSM(Response Surface Methodology) which is widely used for the complex optimization problems is selected as the optimization technique. In particular, to improve the non-linearity of the response and to consider the accuracy and the efficiency of the solution, design space stretching technique has been applied. Separate sub-optimization routine is introduced to determine the stretching position and clustering parameters which construct the optimum regression model. Two step optimization technique has been applied to obtain the optimal system. With the application of stretching technique, we can perform system optimization with a small number of experimental points, and construct precise regression model for highly non-linear domain. The error compared with analysis result is only 0.01% and it is demonstrated that present method can be applied to more practical design optimization problems with many design variables.

• 한국공작기계학회논문집
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• 제18권2호
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• pp.170-177
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• 2009

The objective of this study is to evaluate an acoustic emission (AE) source characterization and fracture behavior of the SM45C steel by using back-propagation neural network (BPN). In previous research Ref. [8] about k-nearest neighbor classifier (k-NNC) continuity, we used K-means clustering method as an unsupervised learning method for obtaining multi-variate AE main data sets, such as AE counts, energy, amplitude, risetime, duration and counts to peak. Similarly, we applied k-NNC and BPN as a supervised learning method for obtaining multi-variate AE working data sets. According to the error of convergence for determinant criterion Wilk's ${\lambda}$, heuristic criteria D&B(Rij) and Tou values are discussed. As a result, in k-NNC before fracture signal is detected or when fracture signal is detected, showed that produce some empty classes in BPN. And we confirmed that could save trouble in AE signal processing if suitable error of convergence or acceptable encoding error give to BPN.

• 한국농업기계학회:학술대회논문집
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• 한국농업기계학회 2000년도 THE THIRD INTERNATIONAL CONFERENCE ON AGRICULTURAL MACHINERY ENGINEERING. V.II
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• pp.279-286
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• 2000

The objective of this research is to detect the papaya fruits on tree in an orchard. The detection of papaya on natural background is difficult because colors of fruits and background such as leaves are similarly green. We cannot separate it from leaves by color information. Therefore, this research will use shape information instead. First, we detect an interested object by detecting its boundary using edge detection technique. However, the edge detection will detect every objects boundary in the image. Therefore, shape description technique will be used to describe which one is the interested object boundary. The good shape description should be invariant in scaling, rotating, and translating. The successful concept is to use Fourier series, which is called "Fourier Descriptors". Elliptic Fourier Descriptors can completely represent any shape, which is selected to describe the shape of papaya. From the edge detection image, it takes a long time to match every boundary directly. The pre-processing task will reduce non-papaya edge to speed up matching time. The deformable template is used to optimize the matching. Then, clustering the similar shapes by the distance between each centroid, papaya can be completely detected from the background.

• 한국지능시스템학회논문지
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• 제15권4호
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• pp.467-472
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• 2005

영상 향상기법들의 주요한 목적은 특정한 응용프로그램에서 결과영상이 원영상보다 보다 적절하게 하기 위해 처리하는 것이다. 야간에 촬영한 영상들은 열약한 주위환경에 기인하여 저대비 영상을 가질 수 있다. 본 논문에서는 클러스터링 알고리듬을 이용한 영상 대비 향상 기법(ICECA)과 히스토그램 평활화(HE), 양분 히스토램 평활화(BBHE), Multi-Scale Retinek(MSR)와 같은 영상 향상 기법들을 비교하였다. 성능 비교를 위해 다양한 영상에 영상 향상기법들을 적용하여 비교하였다.

• 농촌지도와개발
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• 제3권2호
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• pp.247-264
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• 1996

The objective of this study was to analyze the reality of the program development process in detail accomplished by the organizations of extension education in through the hermeneutical approach. To achieve this purpose, this study tried to find answers to the following three questions : (1) how the organization of extension education develop their programs for farmers? (2) what is the programmers' awareness to the process of program development? and what is the reason for their thought and action to do so. (3) can be discussed integrally the findings for drawing some implications? The qualitative data were mainly gathered through participation observation and unstructured interview. And the qualitative data were analyzed by (1) noting pattern and themes, (2) seeing plausibility, (3) clustering, (4) making metaphors, (5) factoring, and (6) building a logical chain of evidence which hermeneutical techniques far drawing the meaning from the gathered data. The findings of this study were as follows: The programmers of this organization carried out the developing program in the technical training division at the national level and the section of fostering farm manager at the county level for the purpose of delivering the agricultural new technology and the agricultural policy. The term used formly in this organization was `curriculum development for former', and the reality of program was `instruction profile` which signified the set of the educational manin contents. At county level, Educational planning was stressed on the implement of educational administration.

• 아동학회지
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• 제32권1호
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• pp.13-29
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• 2011

The objective of this study was to identify role types as they pertain to paternal and maternal grandmothers based on four role dimensions. To this end, a sample of 416 mothers of preschoolers was used. This study also examined correlates of and differences in the type of grandparents in terms of paternal and maternal types of grandmothers. Data were analyzed by K-means clustering, Chi-square, and multi-nominal logistic regression analysis. Grandmothers were classified into five distinct groups : influential, supportive, authority-oriented, passive, and detached types. Maternal grandmothers seemed to be relatively more involved with their grandchildren than paternal ones. The type of grandmothers varied as a function of socioeconomic status, the number of grandchildren, and geographical proximity for paternal grandmothers, and mothers' employment status and the closeness between grandmothers and mothers for maternal grandmothers. The results imply that grandmothers are currently becoming more active in their grandchildren's lives and that kinship in Korean society tends to lean to the maternal side.

• Journal of Communications and Networks
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• 제18권4호
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• pp.580-588
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• 2016

Energy efficiency is the main objective in the design of a wireless sensor network (WSN). In many applications, sensing data must be transmitted from sources to a sink in a timely manner. This paper describes an investigation of the trade-off between two objectives in WSN design: minimizing energy consumption and minimizing end-to-end delay. We first propose a new distributed clustering approach to determining the best clusterhead for each cluster by considering both energy consumption and end-to-end delay requirements. Next, we propose a new energy-cost function and a new end-to-end delay function for use in an inter-cluster routing algorithm. We present a multi-hop routing algorithm for use in disseminating sensing data from clusterheads to a sink at the minimum energy cost subject to an end-to-end delay constraint. The results of a simulation are consistent with our theoretical analysis results and show that our proposed performs much better than similar protocols in terms of energy consumption and end-to-end delay.