• Proceedings of the Korea Water Resources Association Conference
• /
• 2011.05a
• /
• pp.87-91
• /
• 2011

강수는 지역에 따라 발생양상이 매우 다른 자연현상 중 하나이다. 이러한 강수를 효과적으로 분석하여 확률강수량을 산정하기위해서 수문학에서는 다양한 방법이 시도되어 왔다. 우리나라에서는 지점빈도해석을 통한 확률강수량을 주로 사용해왔으나 최근 들어 Hosking and Wallis(1997)가 제안한 지역빈도해석을 활용을 적극 도모 하고 있는 중이다. 이러한 지역빈도해석 기법은 지점빈도해석 기법에 비하여 한정된 강수자료를 활용하는 측면 등 여러 가지 장점을 가진 확률 강수량 산정방법이다. 그러나 이 기법을 적용하여 확률강수량을 산정하기 위해서는 강수의 지역구분을 먼저 수행하여야 한다. 강수지역의 구분을 위해서는 여러 가지 기법이 존재하나 최근에는 Cluster 기법 중 K-means 방법이나 Fuzzy c-means 방법 등을 주로 적용하여 지역구분을 수행하고 있다. 그러나 K-means 방법이나 Fuzzy c-means 방법 등은 산정 방법내에서 최적 군집수를 결정할 수 있는 알고리즘이 없기 때문에 임의적으로 최적 군집수를 결정하여야 한다. 본 연구에서는 이러한 단점을 극복하기 위하여 Cluster 평가지수 중 하나인 Dunn 지수를 이용하여 최적 군집수를 제시하고자 한다. 본 연구에서 강수지역을 구분하기 위하여 적용한 인자는 월 평균 강수량, 연 평균 강수량, 월 최대 강수량, 경도, 위도, 고도 등이며, 이를 K-means, PAM 및 친근도 전파 기법을 통하여 강수지역을 구분하였다. 적정 군집수를 임의적으로 증가시켜 가면서 Dunn 지수를 산정하였다. 산정된 결과를 통하여 최적 군집수를 결정하였다.

• Journal of Korea Society of Digital Industry and Information Management
• /
• v.16 no.3
• /
• pp.13-23
• /
• 2020

Currently, online means of replacing resident registration numbers(RRN) include I-Pin, mobile phone, credit card, MyPin, and general-purpose certificate. In order to issue alternative means based on the RRN, it must be designated through the designation review by the Korea Communications Commission(KCC) through a designation review by personal proofing agency and be subject to annual management. However, the criteria for designation and follow-up of the designation of the personal proofing agency carried out by KCC have been used in 2010 without revision, and there are problems that do not conform to the evaluation standards of various alternative means. Therefore, in this paper, we propose a method for improving the designation criteria and management system of the personal proofing service agency. The proposed method analyzes the characteristics of the alternative identification-based personal proofing service and proposes a follow-up management standard that can appropriately evaluate the analyzed characteristics and improves the designation criteria according to the emergence of new alternatives. Through the proposed method, it can be seen that it is possible to strengthen the safety of the personal proofing service based on the alternative means of RRN provided online and face-to-face and to protect the user's personal information.

• Journal of Digital Convergence
• /
• v.13 no.2
• /
• pp.135-140
• /
• 2015

General CHMM vocabulary recognition system is model observation probability for vocabulary recognition of recognition rate's low. Used as the limiting unit is applied only to some problem in the phoneme model. Also, they have a problem that does not conform to the needs of the search range to meaning of the words in the vocabulary. Performs a phoneme recognition using GMM to improve these problems. We solve the problem according to the limited search words characterized by an improved k-means algorithm. Measure the effectiveness represented by the accuracy and reproducibility as compared to conventional system performance experiments. Performance test results accuracy is 83%p, and recall is 67%p.

• Journal of Surface Science and Engineering
• /
• v.54 no.5
• /
• pp.278-284
• /
• 2021

Corrosion of steel plate is common phenomenon which results in the gradual destruction caused by a wide variety of environments. Corrosion monitoring is the tracking of the degradation progress for a long period of time. Corrosion on steel plate appears as a discoloration and any irregularities on the surface. In this study, we developed a quantitative evaluation method of the rust formed on steel plate by using k-means clustering from the corroded area in a given image. The k-means clustering for automated corrosion detection was based on the GrabCut segmentation and Gaussian mixture model(GMM). Image color of the corroded surface at cut-edge area was analyzed quantitatively based on HSV(Hue, Saturation, Value) color space.

• Journal of the Korea Convergence Society
• /
• v.10 no.1
• /
• pp.291-298
• /
• 2019

This study aimed to examine disabled women to determine whether differences existed in parenting stress, resilience, social support, and parenting competency based on the disability type using an latent means analysis. The research data was sampled from 167 mentally disabled women and 132 physically disabled women. Parenting stress and social support had higher latent means in the mentally disabled women. Parenting competence and resilience had higher latent means in the physically disabled women. The results of this study suggested that differentiated, practical intervention approaches should be implemented for each disability type.

• Journal of the Korea Institute of Information Security & Cryptology
• /
• v.31 no.1
• /
• pp.1-9
• /
• 2021

This paper proposes to automate the process of predicting crypto-operations from the power signal generated in RSA decoding process by frequency analysis and K-means algorithm. RSA decoding process is divided into square and multiply operation, and if we can predict the type of operations over time, we will know the RSA key value. After converting the power signal generated in the process of decoding into two-dimensional frequency signal, this paper used K-means algorithm to classify the frequency vector according to the type of operation. these classified frequency vector were used to predict the types of operations.

• The Journal of the Korea institute of electronic communication sciences
• /
• v.17 no.4
• /
• pp.703-708
• /
• 2022

K-means clustering is a representative clustering technique. However, there is a limitation in not being able to integrate the performance evaluation scale and the method of determining the minimum number of clusters. In this paper, a method for numerically determining the minimum number of clusters is introduced. The explained variance is presented as an integrated measure. We propose that the k-means clustering method should be performed in the subspace of the PCA in order to simultaneously satisfy the minimum number of clusters and the threshold of the explained variance. It aims to present an explanation in principle why principal component analysis and k-means clustering are sequentially performed in pattern recognition and machine learning.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
• /
• 2021.05a
• /
• pp.447-449
• /
• 2021

Various wireless sensor network protocols have been proposed to maintain the network for a long time by minimizing energy consumption. Using the K-means clustering algorithm takes longer to cluster than traditional hierarchical algorithms because the center point must be moved repeatedly until the final cluster is established. For K-means clustering-based protocols, only the residual energy of nodes or nodes near the center point of the cluster is considered when the cluster head is elected. In this paper, we propose a new wireless sensor network protocol based on K-means clustering to improve the energy efficiency while improving the aforementioned problems.

• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.23 no.5
• /
• pp.1-8
• /
• 2023

Cross-domain recommendation is a method that shares related user information data and item data in different domains. It is mainly used in online shopping malls with many users or multimedia service contents, such as YouTube or Netflix. Through K-means clustering, embeddings are created by performing clustering based on user data and ratings. After learning the result through a transformer network, user satisfaction is predicted. Then, items suitable for the user are recommended using a transformer-based recommendation model. Through this study, it was shown through experiments that recommendations can predict cold-start problems at a lesser time cost and increase user satisfaction.

• Journal of Physiology & Pathology in Korean Medicine
• /
• v.18 no.4
• /
• pp.953-956
• /
• 2004

We studied on the means to ascetic practices centering around Taijiquan. Taijiquan is the means to the self-discipline of the human body. And Taijiquan is the regimen for human health. Therefore according to the continuous training of Taijiquan, we can achieve the purpose of the ascetic practices by the getting over the body's habituations.