• Proceedings of the Korea Information Processing Society Conference
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• 2018.10a
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• pp.279-281
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• 2018

랜섬웨어는 사용자의 중요 파일을 암호화한 후 금전을 요구하는 형태의 악성코드로, 전 세계적으로 큰 피해를 발생시켰다. 안드로이드 환경에서의 랜섬웨어는 앱을 통해 동작하기 때문에, 앱의 악의적인 암호화 기능 수행을 실시간으로 탐지할 수 있는 방안에 대한 연구들이 진행되고 있다. 자원 제한적인 안드로이드 환경에서 중요한 파일들에 대한 암호화 수행 여부를 실시간으로 탐지하기 위한 방안으로 Shannon 엔트로피 값 비교가 있다. 하지만 파일의 종류에 따라 Shannon 엔트로피 값이 크게 달라질 수 있으며, 암호화 기능 수행에 대한 오탐이 발생할 수 있다. 따라서 본 논문에서는 파일에 대한 분할된 Shannon 엔트로피 값을 측정하여 암호화 기능 수행 탐지의 정확성을 높이고자 한다.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.49 no.1
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• pp.11-18
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• 2012

In this paper, an entropy constrained vector quantizer for high bit-rates is proposed. The sample-adaptive product quantizer (SAPQ), which is based on the product codebooks, is employed, and a design algorithm for the entropy constrained sample adaptive product quantizer (ECSAPQ) is proposed. The performance of the proposed ECSAPQ is better than the case of the entropy constrained vector quantizer by 0.5dB. It is also shown that the ECSAPQ distortion curve, which is based on the scalar quantizer, is lower than the high-rate theoretical curve of the entropy constrained scalar quantizer, where the theoretical curve have 1.53dB difference from Shannon's lower bound.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2002.11b
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• pp.176-181
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• 2002

The continuous Gabor wavelet transform (GWT) has been utilized as a useful time-frequency analysis tool to identify the rapidly-varying characteristics of some wave signals. In the application of GWT, it is important to select the Gabor wavelet with the optimal shape factor by which the time-frequency distribution of a signal can be accurately estimated. To find the signal-dependent optimal Gabor wavelet shape factor, the notion of the Shannon entropy which mesures the extent of signal energy concentration in the time-frequency plane is employed. To verify the validity of the present entropy-based scheme, we have applied it to the time-frequency analysis of a set of elastic bending wave signals generated by an impact in a solid cylinder.

• Journal of the Institute of Convergence Signal Processing
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• v.16 no.4
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• pp.134-138
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• 2015

Heart sound is used for a basic clinical examination to check for abnormalities in the lungs and heart that can be heard with a stethoscope or phonocardiography. In this paper, we try to find an easier and non-invasive method to diagnose heart diseases using neural network classifier. The classifier has been developed for one normal heart sound and five murmurs by using Shannon entropy and conjugate scaled back propagation algorithm. The experimental results showed that the classification is possible with 1.63185e-6 of classification error.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.18 no.2
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• pp.89-103
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• 2018

A genius "Prince of Mathematician" Gaussian and "Father of Communication" Shannon comes up with the creative idea of motivation to meet each other? The answer is a coin leaf. Gaussian found some creative ideas in the matter of obtaining a sum of 1 to 100. This is the same as the probability distribution curve when a coin leaf is thrown. Shannon extended the Gaussian probability distribution to define the entropy, taking the source symbol and the reciprocal logarithm to obtain the weighted average. These where the genius Gaussian and Shannon meet in the same coin leaf. This paper focuses on this point, and easily proves Gaussian distribution and Shannon entropy. As an application example, we have obtained the capacity and transition probability of Jeongju seminal vesicle, and the Shannon channel capacity is 1 when the equivalent transition probability is 1/2.

• Journal of the Korean Institute of Telematics and Electronics
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• v.17 no.2
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• pp.23-28
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• 1980

The foundation of information theory mainly established by C. E. Shannon , opened the way to profuse studies on the linguistics of various languages. The statistics of Korean letters composed of elements and space are analyzed. The Korean alphabetic elements including the space have their probabilities . And information techniques can be applied to them. This paper extended the previous statistics of Korean letters to include the space. We have also calculated the entropies and redundancy for the case. The result can be used to modify the evaluation of Korean letter information processing devices and used as the basis for letter coding method for eventual future information processors.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2002.11a
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• pp.324.1-324
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• 2002

The continuous Gabor wavelet transform (GWT) has been utilized as a useful time-frequency analysis tool to identify the rapidly-varying characteristics of some wave signals. In the application of GWT, it is important to select the Gabor wavelet with the optimal shape factor by which the time-frequency distribution of a signal can be accurately estimated. To find the signal-dependent optimal Gator wavelet shape factor, the notion of the Shannon entropy which measures the extent of signal energy concentration in the time-frequency plane is employed. (omitted)

• Proceeding of EDISON Challenge
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• 2017.03a
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• pp.75-81
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• 2017

Polymer collapse transition에 대한 연구가 많이 진행되어왔다. 허나 각각의 microstate에 대한 entropy나 free energy에 대한 계산을 하지는 못하였다. 최근 local nonequilibrium thermodynamics와 관련한 논문이 발표되었는데 이는 비평형 상태에서의 각각의 microstate에 대한 확률 분포를 결정하는 물리량을 발견 및 특성을 규명하여 이 중 특별한 상태가 지니는 "information" 이라는 양이 내부에너지와 엔트로피와의 상관관계가 있음을 보였다. 또한, 이러한 information theory를 이용한 Shannon entropy를 사용하여 entropy를 정의하고 free energy와 같은 물리량을 계산하였다. 따라서 이를 이용하여 information theory를 이용한 Shannon entropy와 이로 정의된 free energy를 이용하여 polymer collapse중 entropy 및 free energy를 계산하였다.

• Information and Communications Magazine
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• v.25 no.5
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• pp.5-13
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• 2008

정보 이론은 최대한 많은 데이터를 매체에 저장하거나 채널을 통해 통신하기 위해 데이터를 정량화하는 응용 수학의 한 분야이다. 1948년 정보이론은 Shannon의 논문에서 발표되었으며 이 논문을 바탕으로 통신, 신호처리, 네트워크에의 데이터 처리 및 전송에 대한 획기적인 발전을 이루었다. 본 논고에서는 정보의 의미와 엔트로피, 채널 용량에 관한 내용을 다루어 정보이론의 기본 개념을 설명할 것이며, 또한 센서네트워크와 중계 채널 그리고 MIMO 시스템과 다른 분야에서 정보이론이 어떻게 적용되는지 그 응용분야에 대해 다뤄보고자 한다.

• The Transactions of the Korean Institute of Electrical Engineers D
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• v.55 no.3
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• pp.131-137
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• 2006

The secondary system of nuclear power plants consists of sophisticated piping systems operating in very aggressive erosion and corrosion environments, which make a piping system vulnerable to the wear and degradation due to the several chemical components and high flow rate (~10 m/sec) of the coolant. To monitor the wear and degradation on a pipe, the vibration signals are measured from the pipe with an accelerometer For analyzing the vibration signal the time-frequency analysis (TFA) is used, which is known to be effective for the analysis of time-varying or transient signals. To reduce the inteferences (cross-terms) due to the bilinear structure of the time-frequency distribution, an adaptive cone-kernel distribution (ACKD) is proposed. The cone length of ACKD to determine the characteristics of distribution is optimally selected through an adaptive algorithm using the normalized Shannon's entropy And the ACKD's are compared with the results of other analyses based on the Fourier Transform (FT) and other TFA's. The ACKD shows a better signature for the wear/degradation within a pipe and provides the additional information in relation to the time that any analysis based on the conventional FT can not provide.