• Title/Summary/Keyword: code vector

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Image Coding Using the Self-Organizing Map of Multiple Shell Hypercube Struture (다중쉘 하이퍼큐브 구조를 갖는 코드북을 이용한 벡터 양자화 기법)

  • 김영근;라정범
    • Journal of the Korean Institute of Telematics and Electronics B
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    • v.32B no.11
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    • pp.153-162
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    • 1995
  • When vector quantization is used in low rate image coding (e.g., R<0.5), the primary problem is the tremendous computational complexity which is required to search the whole codebook to find the closest codevector to an input vector. Since the number of code vectors in a vector quantizer is given by an exponential function of the dimension. i.e., L=2$^{nR}$ where Rn. To alleviate this problem, a multiple shell structure of hypercube feature maps (MSSHFM) is proposed. A binary HFM of k-dimension is composed of nodes at hypercube vertices and a multiple shell architecture is constructed by surrounding the k-dimensional hfm with a (k+1)-dimensional HFM. Such a multiple shell construction of nodes inherently has a complete tree structure in it and an efficient partial search scheme can be applied with drastically reduced computational complexity, computer simulations of still image coding were conducted and the validity of the proposed method has been verified.

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PMSM Drive System Using Embedded Target for TI C2000 DSP in MATLAB/SIMULINK (MATLAB/SIMULINK의 TI C2000 DSP 임베디드 타겟을 이용한 동기 전동기 구동 시스템)

  • Lee, Yong-Seok;Ji, Jun-Keun;Cha, Gui-Soo
    • Proceedings of the KIPE Conference
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    • 2007.07a
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    • pp.400-402
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    • 2007
  • This paper presents a vector control implementation for PMSM using Real Time Workshop and Embedded Target for TI C2000 DSP in MATLAB/SIMULINK. Speed, current and vector controllers are easily designed and implemented by using the MATLAB/SIMULINK program. Feedback of motor speed is processed through C28x QEP(Quadrature Encoder Pulse) block from encoder pulse. 3-Phase currents ares processed through C28x ADC block from current sensors. And gating signal of PWM inverter is generated through SVPWM and PWM block. Real-time program is drawn using SIMULINK and then converted program code for speed control of PMSM is downloaded into the TI eZdsp 2812 board. Experiments were carried out to examine validity of the proposed vector control implementation.

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A Study on Gender Classification Based on Diagonal Local Binary Patterns (대각선형 지역적 이진패턴을 이용한 성별 분류 방법에 대한 연구)

  • Choi, Young-Kyu;Lee, Young-Moo
    • Journal of the Semiconductor & Display Technology
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    • v.8 no.3
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    • pp.39-44
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    • 2009
  • Local Binary Pattern (LBP) is becoming a popular tool for various machine vision applications such as face recognition, classification and background subtraction. In this paper, we propose a new extension of LBP, called the Diagonal LBP (DLBP), to handle the image-based gender classification problem arise in interactive display systems. Instead of comparing neighbor pixels with the center pixel, DLBP generates codes by comparing a neighbor pixel with the diagonal pixel (the neighbor pixel in the opposite side). It can reduce by half the code length of LBP and consequently, can improve the computation complexity. The Support Vector Machine is utilized as the gender classifier, and the texture profile based on DLBP is adopted as the feature vector. Experimental results revealed that our approach based on the diagonal LPB is very efficient and can be utilized in various real-time pattern classification applications.

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Smart-phone Malicious Code Countermeasure System (스마트폰 악성코드 대응 시스템)

  • Song, Jong-Gun;Lee, HoonJae;Kim, TaeYong;Jang, WonTae
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2013.05a
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    • pp.223-226
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    • 2013
  • Information security breaches caused by malicious code is arising in various forms with exponential growth. The latest information security threats on computers are increasing, especially on smartphone, which has enabled malicious code to quickly surge. As a result, the leakage of personal information, such as billing information, is under threat. Meanwhile the attack vector o smartphone malware is difficult to detect. In this paper, we propose a smartphone security system to respond to the spread of malicious code by iPhone and Android OS-based malware analysis.

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A New Extension Method for Minimal Codes (극소 부호의 새로운 확장 기법)

  • Chung, Jin-Ho
    • Journal of IKEEE
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    • v.26 no.3
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    • pp.506-509
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    • 2022
  • In a secret sharing scheme, secret information must be distributed and stored to users, and confidentiality must be able to be reconstructed only from an authorized subset of users. To do this, secret information among different code words must not be subordinate to each other. The minimal code is a kind of linear block code to distribute these secret information not mutually dependent. In this paper, we present a novel extension technique for minimal codes. The product of an arbitrary vector and a minimal code produces a new minimal code with an extended length and Hamming weight. Accordingly, it is possible to provide minimal codes with parameters not known in the literature.

An online Calibration Algorithm using binary spreading code for the CDMA-based Adaptive Antenna Array

  • Lee, Chong-Hyun
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.20 no.9
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    • pp.32-39
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    • 2006
  • In this paper, an iterative subspace-based calibration algorithm for a CDMA-based antenna array in the presence of unknown gain and phase error is presented. The algorithm does not depend on the array geometry and does not require a prior knowledge of the Directions Of Arrival (DOA) of the signals. The method requires the code sequence of a reference user only. The proposed algorithm is based on the subspace method and root finding approach, and it provides estimates of the calibration vector, the DOA and the channel impulse response, by using the code sequence of a reference user. The performance of the proposed algorithm was investigated by means of computer simulations and was verified using field data measured through a custom-built W-CDMA test-bed. The data show that experimental results match well with the theoretical calibration algorithm. Also, teh study propose an efficient algorithm using the simulated annealing technique. This algorithm overcomes the requirement of initial guessing in the subspace-based approach.

Malware Detection Method using Opcode and windows API Calls (Opcode와 Windows API를 사용한 멀웨어 탐지)

  • Ahn, Tae-Hyun;Oh, Sang-Jin;Kwon, Young-Man
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.17 no.6
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    • pp.11-17
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    • 2017
  • We proposed malware detection method, which use the feature vector that consist of Opcode(operation code) and Windows API Calls extracted from executable files. And, we implemented our feature vector and measured the performance of it by using Bernoulli Naïve Bayes and K-Nearest Neighbor classifier. In experimental result, when using the K-NN classifier with the proposed method, we obtain 95.21% malware detection accuracy. It was better than existing methods using only either Opcode or Windows API Calls.

Gesture Recognition Method using Tree Classification and Multiclass SVM (다중 클래스 SVM과 트리 분류를 이용한 제스처 인식 방법)

  • Oh, Juhee;Kim, Taehyub;Hong, Hyunki
    • Journal of the Institute of Electronics and Information Engineers
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    • v.50 no.6
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    • pp.238-245
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    • 2013
  • Gesture recognition has been widely one of the research areas for natural user interface. This paper presents a novel gesture recognition method using tree classification and multiclass SVM(Support Vector Machine). In the learning step, 3D trajectory of human gesture obtained by a Kinect sensor is classified into the tree nodes according to their distributions. The gestures are resampled and we obtain the histogram of the chain code from the normalized data. Then multiclass SVM is applied to the classified gestures in the node. The input gesture classified using the constructed tree is recognized with multiclass SVM.

A design of Context-Based Adaptive Variable Length Coder For H.264 (H.264용 Context-Based Adaptive Variable Length Coder(CAVLC) 설계)

  • Lee, Hong-Sic;Suh, Ki-Bum
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • v.9 no.2
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    • pp.237-240
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    • 2005
  • This paper propose an novel CAVLC architcture for H.264 and designed the CAVLC module which can be used in AMBA based design. This designed module can be operated in 420 cycle for one-macroblock and support both long-start code method using Annex B.1 and RTP. To verify the CAVLC architecture, we developed the reference C from JM8.5 and verified the our developed hardware using test vector generated by reference C. The designed circuit can be operated in 54MHz clock system, and has 14096 gate counts using Hynix 0.35 um TLM process.

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