• Title/Summary/Keyword: Shannon

Search Result 545, Processing Time 0.027 seconds

ON THE GIBBS PHENOMENON FOR THE SHANNON SAMPLING SERIES IN WAVELET SUBSPACES AND A WAY TO GO AROUND

  • Shim, Hong-Tae
    • Communications of the Korean Mathematical Society
    • /
    • v.13 no.1
    • /
    • pp.181-193
    • /
    • 1998
  • The Shannon sampling series is the prototype of an interpolating series or sampling series. Also the Shannon wavelet is one of the protypes of wavelets. But the coefficients of the Shannon sampling series are different function values at the point of discontinuity, we analyze the Gibbs phenomenon for the Shannon sampling series. We also find a way to go around this overshoot effect.

  • PDF

Optimal Placement of Sensors for Damage Detection in a Structure and its Application (구조물의 손상탐지를 위한 센서 위치 최적화 및 적용)

  • 박수용
    • Journal of the Earthquake Engineering Society of Korea
    • /
    • v.7 no.4
    • /
    • pp.81-87
    • /
    • 2003
  • In this paper, the feasibility of using Shannon's sampling theorem to reconstruct exact mode shapes of a structural system from a limited number of sensor points and localizing damage in that structure with reconstructed mode shapes is investigated. Shannon's sampling theorem for the time domain is reviewed. The theorem is then extended to the spatial domain. To verify the usefulness of extended theorem, mode shapes of a simple beam are reconstructed from a limited amount of data and the reconstructed mode shapes are compared to the exact mode shapes. On the basis of the results, a simple rule is proposed for the optimal placement of accelerometers in modal parameter extraction experiments. Practicality of the proposed rule and the extended Shannon's theorem is demonstrated by detecting damage in laboratory beam structure with two-span via applying to mode shapes of pre and post damage states.

ON GIBBS CONSTANT FOR THE SHANNON WAVELET EXPANSION

  • Shim, Hong-Tae
    • Journal of applied mathematics & informatics
    • /
    • v.4 no.2
    • /
    • pp.529-534
    • /
    • 1997
  • Even though the Shannon wavelet is a prototype of wavelets are assumed to have. By providing a sufficient condition to compute the size of Gibbs phe-nomenon for the Shannon wavelet series we can see the overshoot is propotional to the jump at discontinuity. By comparing it with that of the Fourier series we also that these two have exactly the same Gibbs constant.

Meeting of Gauss and Shannon at Coin Leaf in 5G Massive MIMO (5G Massive MIMO에서 가우스(Gauss)와 샤논(Shannon)이 동전 한 닢에서 만남)

  • Kim, Jeong-Su;Lee, Moon-Ho;Park, Daechul
    • The Journal of the Institute of Internet, Broadcasting and Communication
    • /
    • v.18 no.2
    • /
    • pp.89-103
    • /
    • 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.

A Meeting of Euler and Shannon (오일러(Euler)와 샤논(Shannon)의 만남)

  • Lee, Moon-Ho
    • The Journal of the Institute of Internet, Broadcasting and Communication
    • /
    • v.17 no.1
    • /
    • pp.59-68
    • /
    • 2017
  • The flower and woman are beautiful but Euler's theorem and the symmetry are the best. Shannon applied his theorem to information and communication based on Euler's theorem. His theorem is the root of wireless communication and information theory and the principle of today smart phone. Their meeting point is $e^{-SNR}$ of MIMO(multiple input and multiple output) multiple antenna diversity. In this paper, Euler, who discovered the most beautiful formula($e^{{\pi}i}+1=0$) in the world, briefly guided Shannon's formula ($C=Blog_2(1+{\frac{S}{N}})$) to discover the origin of wireless communication and information communication, and these two masters prove a meeting at the Shannon limit, It reveals something what this secret. And we find that it is symmetry and element-wise inverse are the hidden secret in algebraic coding theory and triangular function.

Very Efficient 6-ary Runlength-Limited Code Approaching Shannon Capacity for Optical Storage Channels (Shannon Capacity에 근접하는 고효율의 6-ary Runlength-Limited Code)

  • Jhee, Yoon-Kyoo
    • Journal of the Institute of Electronics Engineers of Korea SD
    • /
    • v.45 no.3
    • /
    • pp.29-35
    • /
    • 2008
  • Very efficient 6-ary runlength-limited codes for a six-level optical recording channel are presented when d = 3. The 6-ary(3, 15) code of rate 6/7 is given achieving coding efficiency of 98.87%. The efficiency of rate 13/15, (3, 20) code is 99.95%, which approaches the Shannon capacity. To increase the accurary of reading 6-ary signal, partial response modes are also investigated.

Accuracy Enhancement of Determining File Encryption Status through Divided Shannon Entropy (분할된 Shannon 엔트로피 값을 이용한 파일 암호화 판별 정확성 향상에 대한 연구)

  • Ko, Ju-Seong;Kwak, Jin
    • Annual Conference of KIPS
    • /
    • 2018.10a
    • /
    • pp.279-281
    • /
    • 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.

A Study on the Relative Motivation of Shannon's Information Theory (샤논 정보이론의 상관성 동기에 관한 연구)

  • Lee, Moon-Ho;Kim, Jeong-Su
    • The Journal of the Institute of Internet, Broadcasting and Communication
    • /
    • v.21 no.3
    • /
    • pp.51-57
    • /
    • 2021
  • In this paper, the relevance between Einstein's special theory of relativity (1905) and Bernoulli's fluid mechanics (1738), which motivates Shannon's theorem (1948), was derived from the AB=A/A=I dimension, and the Shannon's theorem channel code was simulated. When Bernoulli's fluid mechanics ΔP=pgh was applied to the Hallasan volcano Magma eruption, the dimensions and heights matched the measured values. The relationship between Einstein's special theory of relativity, Shannon's information theory, and the stack effect theory of fluid mechanics was analyzed, and the relationship between volcanic eruptions was mathematically proven. Einstein's and Bernoulli's conservation of energy and conservation of mass were the same in terms of bandwidth and power efficiency in Shannon's theorem.

Improvement of the Shannon Approximation to Correct Effects of Mid-spatial Frequency Wavefront Errors of Concentric Ring Structure in MTF Prediction of Optical Systems (광학계의 MTF 예측에서 동심원 구조의 중간 공간 주파수 파면 오차의 영향이 보정된 Shannon 근사식)

  • Seong-Ho Bae;Ho-Soon Yang;In-Ung Song;Sang-Won Park;Hakyong Kihm;Jong Ung Lee
    • Korean Journal of Optics and Photonics
    • /
    • v.35 no.5
    • /
    • pp.210-217
    • /
    • 2024
  • We investigate the effects of mid-spatial frequency wavefront errors on the modulation transfer function (MTF) of optical imaging systems such as airborne cameras and astronomical telescopes. To reduce the prediction error of the MTF, an improved Shannon approximation is proposed. The Shannon approximation is useful for low-order wavefront errors, but it has limitations in predicting MTF with high-order wavefront errors, especially those caused by mid-spatial frequency errors from the manufacturing process of aspheric optical components. In this study, we analyze the impacts of concentric ring-shaped mid-spatial frequency wavefront errors on the MTF using MATLAB and Code V simulations and propose a method to improve the Shannon approximation, which has a new correction factor (K-factor).

A Study on Heart Sound Analysis Using Wavelet and Average Shannon Energy (웨이브렛과 평균 Shannon 에너지를 이용한 심음 신호 분석에 관한 연구)

  • Jang, Kwen-Se;Yao, Chao;Kim, Dong-Jun
    • Proceedings of the KIEE Conference
    • /
    • 2011.07a
    • /
    • pp.2051-2052
    • /
    • 2011
  • The structural defects of a heart often reflects the sounds that the heart produces. This paper describes heart sound analysis method using Wavelet transform and average Shannon energy. This can extract the features of heart sounds in various disease identify the heart sounds. Experimental results show that the presented method has potential application in detecting various heart diseases.

  • PDF