• 전자공학회논문지
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• 제50권7호
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• pp.175-180
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• 2013

본 논문에서는 멀티미디어 콘텐츠의 부정자를 추적하기 위하여, 공모된 핑거프린팅 코드를 해밍거리를 이용하여 XOR 공모공격을 분류하는 알고리즘을 제안한다. 기존의 공모된 핑거프린팅 코드는 상관관계수를 이용하여 부정자를 판정하였지만 제안된 방법은 해밍거리를 이용하였다. 그 결과 상관관계 계수에 의한 XOR 공모공격은 XOR의 심각한 선형문제 때문에 50% 정도의 공모자 수에서 불가능 했던 부정자 추적이 해밍거리를 이용하여 최소한 1명의 부정자를 추적할 수 있는 추적도의 성능을 향상시켰으므로, 제안된 부정자 추적의 기능동작은 Probabilistic Scheme에 부합하였다.

• 한국통신학회논문지
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• 제18권11호
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• pp.1735-1741
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• 1993

주파수 도약 다원접속 통신시스템에 사용될 수 있는 우수한 해밍자기상관성 및 타 상관성 그리고 긴주기를 갖는 새로운 주파수 도약 패턴순이 소개되었다. 주파수 도략 패턴순의 주기는 qk-1, 알파벧 크기는 q, 주파수 도약 패턴군의 크기는 q인데, 여기서 k는 임의의 양의정수 그리고 q는 소수의 정수승이다. 자시상관함수 및 타 상관함수의 최대값은 qk-1(trivial 경우 제외)인데 이것은 최적의 해밍 상관함수에 해당된다. 그리고 주파수 도약 패턴에 있어서 q*q 스퀘어당 평균 충돌의 수는 1보다 작다.

• ETRI Journal
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• 제43권4호
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• pp.746-757
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• 2021

Side-channel attacks pose an inevitable challenge to the implementation of cryptographic algorithms, and it is important to mitigate them. This work identifies a novel data encoding technique based on 1-of-4 codes to resist differential power analysis attacks, which is the most investigated category of side-channel attacks. The four code words of the 1-of-4 codes, namely (0001, 0010, 1000, and 0100), are split into two sets: set-0 and set-1. Using a select signal, the data processed in hardware is switched between the two encoding sets alternately such that the Hamming weight and Hamming distance are equalized. As a case study, the proposed technique is validated for the NIST standard AES-128 cipher. The proposed technique resists differential power analysis performed using statistical methods, namely correlation, mutual information, difference of means, and Welch's t-test based on the Hamming weight and distance models. The experimental results show that the proposed countermeasure has an area overhead of 2.3× with no performance degradation comparatively.

• International Journal of Ocean System Engineering
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• 제2권1호
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• pp.16-23
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• 2012

In this paper we discussed a new methodology for Urdu Character Recognition system using Dempster-Shafer theory which can powerfully estimate the similarity ratings between a recognized character and sampling characters in the character database. Recognition of character is done by five probability calculation methods such as (similarity, hamming, linear correlation, cross-correlation, nearest neighbor) with Dempster-Shafer theory of belief functions. The main objective of this paper is to Recognition of Urdu letters and numerals through five similarity and dissimilarity algorithms to find the similarity between the given image and the standard template in the character recognition system. In this paper we develop a method to combine the results of the different distance measurement methods using the Dempster-Shafer theory. This idea enables us to obtain a single precision result. It was observed that the combination of these results ultimately enhanced the success rate.

• 한국통신학회논문지
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• 제31권4C호
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• pp.318-323
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• 2006

본 논문에서는 주파수 도약 시스템에 사용될 짧은 길이의 도약 수열의 생성법 세가지를 제안한다. 우선, 기존에 알려져 있는 한개 일치수열과 다상 멱 잉여류 수열의 생성법에 대해 설명하고, 한개 일치수열의 변형으로 얻어진 생성법 하나와 다상 멱 잉여류 수열을 이용한 방법 두개를 제안한다. 다상 멱 잉여류 수열에서 '최적 지움위치'를 지운 수열이 제안된 세가지 수열들 중에서 가장 좋은 상관특성을 가지고, 그 다음은 첫번째 위치 지운 수열, 한개 일치 수열의 변형 수열 순으로 상관특성이 좋음을 확인한다. 또한 이들 세 수열이 심볼이 균형성이 우수하고 쉽게 구현될 수 있음을 설명한다.

• 대한전자공학회논문지
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• 제26권12호
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• pp.1886-1902
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• 1989

In this paper we discuss the generating algorithm of Kumar code sequences which are based on generalized bent sequences for FH-CDMA. The code sequence generator was constructed for the shift register stages n=4 over GF (5). Finally we analyze the characteristics fo Hamming correlation between two code sequences and the time-frequency correlatins of the complete waveform with the sinusoidal chips as the elemental waveforms.

• ETRI Journal
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• 제39권3호
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• pp.417-427
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• 2017

This paper investigates the security of constant weight countermeasures, which aim to produce indistinguishable leakage from sensitive variables and intermediate variables, assuming a constant Hamming distance and/or Hamming weight leakages. To investigate the security of recent countermeasures, contrary to many related studies, we assume that the coefficients of the simulated leakage models follow a normal distribution so that we may construct a model with approximately realistic leakages. First, using our simulated leakage model, we demonstrate security holes in these previous countermeasures. Subsequently, in contrast to the hypotheses presented in previous studies, we confirm the resistance of these countermeasures to a standard correlation power analysis (CPA). However, these countermeasures can allow a bitwise CPA to leak a sensitive variable with only a few thousand traces.

• 한국통신학회논문지
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• 제16권5호
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• pp.424-433
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• 1991

In the noncoherent FH/FSK system presence of the multitione jamming and noise, in the case random and 송 structures jamming model, the performance analyzed that random and struetured jamming derived error proability. It is found that error probability and performance when error corecting code used Hamming. BCH, Convolutional code under the worst case partial band jamming interference.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1994년도 하계학술대회 논문집 C
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• pp.1649-1651
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• 1994

This paper presents a new method for estimating partial discharge position using improved cross-correlation technique and neural networks in the power transformer. When ultrasonic signal is occurred by partial discharge, we detected these signals and calculated cross-correlation values with Hamming window. Also, we estimated partial discharge position using neural network with cross-correlation values. In the result of case study, we can estimate more accurately the partial discharge position than any other algorithms.

• Journal of Electrical Engineering and information Science
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• 제1권2호
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• pp.45-51
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• 1996

This paper presents a neural network approach for on-line estimation of partial discharge(PD) location using advanced correlation technique in power transformer. Ultrasonic sensors detect ultrasonic signals generated by a PD and the proposed method calculates time difference between the ultrasonic signals at each sensor pair using the cross-correlation technique applied by moving average and the Hamming window. The neural network takes distance difference as inputs converted from time difference, and estimates the PD location. Case studies showed that the proposed method using advanced correlation technique and a neural network estimated the PD location better than conventional methods.