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A Study on Evolutionary Computation of Fractal Image Compression (프랙탈 영상 압축의 진화적인 계산에 관한 연구)

  • Yoo, Hwan-Young;Choi, Bong-Han
    • The Transactions of the Korea Information Processing Society
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    • v.7 no.2
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    • pp.365-372
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    • 2000
  • he paper introduces evolutionary computing to Fractal Image Compression(FIC). In Fractal Image Compression(FIC) a partitioning of the image into ranges is required. As a solution to this problem there is a propose that evolution computation should be applied in image partitionings. Here ranges are connected sets of small square image blocks. Populations consist of $N_p$ configurations, each of which is a partitioning with a fractal code. In the evolution each configuration produces $\sigma$ children who inherit their parent partitionings except for two random neighboring ranges which are merged. From the offspring the best ones are selected for the next generation population based on a fitness criterion Collage Theorem. As the optimum image includes duplication in image data, it gets smaller in saving space more efficient in speed and more capable in image quality than any other technique in which other coding is used. Fractal Image Compression(FIC) using evolution computation in multimedia image processing applies to such fields as recovery of image and animation which needs a high-quality image and a high image-compression ratio.

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Study of development of Bilge Separator for new IMO Regulation I - Demulsification - (IMO 협약 개정에 따른 Bilge Separator 개발에 관한 연구 I - 에멀젼 분리에 관한 연구 -)

  • Lim Jae-Dong;Park Sang-Ho;Kim In-Soo
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • 2005.10a
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    • pp.175-179
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    • 2005
  • Treatment of Emulsion is very important to development of Bilge Separator for new IMO Regulation. It is too difficult to demulsify the emulsion in the bilge waste water, so we use chemical treatment to break emulsion stability. Broken oil particle is treated by flotation. Bilge Separator on the Ship doesn't have enough time to treat Bilge waste water because of small space in the ship. For the solution to this problem, we experiment to find primary factor as coagulator, pH, and amount of coagulator. As the basis of test, we decided coagulator, pH and quantity of coagulator.

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Building a developmental urban matrix : a Busan city case study (발전주의 도시 매트릭스의 구축 -부산의 강남 따라하기를 사례로 -)

  • Hwang, Jin-Tae
    • Journal of the Korean association of regional geographers
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    • v.22 no.2
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    • pp.331-352
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    • 2016
  • This paper pays attention to the fact that not only Gangnam but also cities outside Seoul that attempt to follow the Gangnam model are deeply involved in Korean developmental urbanism. It examines discursive materials such as newspaper articles, newspaper advertisements and online debates as significant sources of information showing how certain districts are materially and discursively constructed by diverse actors in the national capital and in other cities. The result of in-depth interviews lasting up to two hours reveals local residents' imagined geographies. The article emphasizes that the so-called "Gangnam problem" should be understood as existing beyond the physical, symbolic and administrative boundaries of Gangnam, in cities that follow the Gangnam model. This study helps to provide an epistemological foundation for more equitable, sustainable and de-developmental urbanism.

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The Developement of Moving Bandpass Filter for Improving Noise Reduction of Automative Intake in Rapid Acceleration Using ANC (능동제어기법을 이용한 자동차의 급가속 흡기소음 저감을 위한 Moving Bandpass Filter의 개발)

  • Jeon Kiwon;Oh Jaeeung;Lee Choonghui;Abu Aminudin;Lee Jungyun
    • Transactions of the Korean Society of Automotive Engineers
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    • v.13 no.4
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    • pp.152-159
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    • 2005
  • The method of induction noise reduction can be classified by using passive control or active control method. However, the passive control method has a demerit to reduce the effect of noise reduction to low frequency (below) 500Hz) range and to be limited in a space of the engine room. Whereas, the active control method can overcome the demerit of passive control method. The algorithm of active control is mostly used in LMS (Least-Mean-Square) algorithm because it can obtain the complex transfer function easily in real-time. Especially, Filtered-X LMS (FXLMS) algorithm is applied to an ANC system. However, the convergence performance of LMS algorithm could not match if the FXLMS algorithm is applied to an active control of the induction noise under rapidly accelerated driving conditions. So, in order to solve the problem in this study, the Moving Bandpass Filter(MBPF) was proposed and implemented. The ANC using MBPF for the reduction of the induction noise shows that more noise reduction as 4dB than without MBPF.

Design of Regression Model and Pattern Classifier by Using Principal Component Analysis (주성분 분석법을 이용한 회귀다항식 기반 모델 및 패턴 분류기 설계)

  • Roh, Seok-Beom;Lee, Dong-Yoon
    • The Journal of Korea Institute of Information, Electronics, and Communication Technology
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    • v.10 no.6
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    • pp.594-600
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    • 2017
  • The new design methodology of prediction model and pattern classification, which is based on the dimension reduction algorithm called principal component analysis, is introduced in this paper. Principal component analysis is one of dimension reduction techniques which are used to reduce the dimension of the input space and extract some good features from the original input variables. The extracted input variables are applied to the prediction model and pattern classifier as the input variables. The introduced prediction model and pattern classifier are based on the very simple regression which is the key point of the paper. The structural simplicity of the prediction model and pattern classifier leads to reducing the over-fitting problem. In order to validate the proposed prediction model and pattern classifier, several machine learning data sets are used.

Combining Collaborative, Diversity and Content Based Filtering for Recommendation System (협업적 여과와 다양성, 내용기반 여과를 혼합한 추천 시스템)

  • Shrestha, Jenu;Uddin, Mohammed Nazim;Jo, Geun-Sik
    • Journal of Intelligence and Information Systems
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    • v.14 no.1
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    • pp.101-115
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    • 2008
  • Combining collaborative filtering with some other technique is most common in hybrid recommender systems. As many recommended items from collaborative filtering seem to be similar with respect to content, the collaborative-content hybrid system suffers in terms of quality recommendation and recommending new items as well. To alleviate such problem, we have developed a novel method that uses a diversity metric to select the dissimilar items among the recommended items from collaborative filtering, which together with the input when fed into content space let us improve and include new items in the recommendation. We present experimental results on movielens dataset that shows how our approach performs better than simple content-based system and naive hybrid system.

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Active Facial Tracking for Fatigue Detection (피로 검출을 위한 능동적 얼굴 추적)

  • 박호식;정연숙;손동주;나상동;배철수
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2004.05b
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    • pp.603-607
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    • 2004
  • The vision-based driver fatigue detection is one of the most prospective commercial applications of facial expression recognition technology. The facial feature tracking is the primary technique issue in it. Current facial tracking technology faces three challenges: (1) detection failure of some or all of features due to a variety of lighting conditions and head motions; (2) multiple and non-rigid object tracking and (3) features occlusion when the head is in oblique angles. In this paper, we propose a new active approach. First, the active IR sensor is used to robustly detect pupils under variable lighting conditions. The detected pupils are then used to predict the head motion. Furthermore, face movement is assumed to be locally smooth so that a facial feature can be tracked with a Kalman filter. The simultaneous use of the pupil constraint and the Kalman filtering greatly increases the prediction accuracy for each feature position. Feature detection is accomplished in the Gabor space with respect to the vicinity of predicted location. Local graphs consisting of identified features are extracted and used to capture the spatial relationship among detected features. Finally, a graph-based reliability propagation is proposed to tackle the occlusion problem and verify the tracking results. The experimental results show validity of our active approach to real-life facial tracking under variable lighting conditions, head orientations, and facial expressions.

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On-line Signature Recognition Using Statistical Feature Based Artificial Neural Network (통계적 특징 기반 인공신경망을 이용한 온라인 서명인식)

  • Park, Seung-Je;Hwang, Seung-Jun;Na, Jong-Pil;Baek, Joong-Hwan
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.19 no.1
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    • pp.106-112
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    • 2015
  • In this paper, we propose an on-line signature recognition algorithm using fingertip point in the air from the depth image acquired by Kinect. We use ten statistical features for each X, Y, Z axis to react to changes in Shifting and Scaling of the signature trajectories in three-dimensional space. Artificial Neural Network is a machine learning algorithm used as a tool to solve the complex classification problem in pattern recognition. We implement the proposed algorithm to actual on-line signature recognition system. In experiment, we verify the proposed method is successful to classify 4 different on-line signatures.

A Study of Privacy Protection for Users of Electronic Money Using Blockchain Technology (블록체인 기법을 사용하는 전자화폐 사용자의 프라이버시 보호에 대한 연구)

  • Kang, Yong-Hyeog
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2017.10a
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    • pp.571-572
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    • 2017
  • The blockchain technology that implements electronic money uses decentralized computing and all transactions in a blockchain are open to everyone. This technique seems to guarantee anonymity by performing the transaction on the address instead of the user, but by using direction acyclic graph based on the transaction graph, the privacy problem is caused by tracking the addresses. In this paper, we analyze various techniques for centralized processing which makes it difficult to find the relevance on the graph in order to protect the privacy in the block chain technology. We also analyze the techniques of anonymizing in a distributed way to enhance privacy. Using the zero knowledge proof scheme guarantees full distributed anonymity but requires more computation and storage space, and various techniques to make this efficient are proposed. In this paper, we propose a privacy protection scheme of blockchain technology to integrate existing privacy protection techniques into a blockchain technology and perform it more efficiently with a centralized or decentralized technique.

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Compression Methods for Time Series Data using Discrete Cosine Transform with Varying Sample Size (가변 샘플 크기의 이산 코사인 변환을 활용한 시계열 데이터 압축 기법)

  • Moon, Byeongsun;Choi, Myungwhan
    • KIISE Transactions on Computing Practices
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    • v.22 no.5
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    • pp.201-208
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    • 2016
  • Collection and storing of multiple time series data in real time requires large memory space. To solve this problem, the usage of varying sample size is proposed in the compression scheme using discrete cosine transform technique. Time series data set has characteristics such that a higher compression ratio can be achieved with smaller amount of value changes and lower frequency of the value changes. The coefficient of variation and the variability of the differences between adjacent data elements (VDAD) are presumed to be very good measures to represent the characteristics of the time series data and used as key parameters to determine the varying sample size. Test results showed that both VDAD-based and the coefficient of variation-based scheme generate excellent compression ratios. However, the former scheme uses much simpler sample size decision mechanism and results in better compression performance than the latter scheme.