Interpolating between Optimal Transport and MMD using Sinkhorn Divergences

Reading notes on Interpolating between Optimal Transport and MMD using Sinkhorn Divergences

The purpose of this paper is to show that the Sinkhorn divergences are convex, smooth, positive definite loss functions that metrize the convergence in law.

Countless methods in machine learning and image processing reley on comparisons betwen probability distributions. But simple dissimilarities such as the Total Variation norm or the Kullback-Leibler relative entropy do not take into account the distance d on the feature space χ\chi. As a result, they do not metrize the convergence in law and are unstable with respect to deformations of the distributions’ support. Optimal Transport distances (sometimes refeered as Earth Mover’s Distance) and Maximum Mean Discrepancies are continuous with respect to convergence in law and metrize its topology when feature space χ\chi is compact.

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Caeser's cipher and Diffie-Hallman key exchange

CipherDisk2000 from Wikipedia

In my IoT class, one of my coursework is to implement a Diffie-Hallman key exchange algorithm which is used to exchange data without leaking safty information in the network communications. In my experiment, some communications take place between a client and a server, the transmitted data have been encrypted and decrypt with Caeser’s cipher when sent to the server from client after the connection is built. So my task is just to add Diffie-Hallman key exchange to secure a message delivery. In this article, I’ll introduce two algorithms, Caeser’s cipher or shift cipher[1] and Diffie-Hallman key exchange.

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连续和离散是什么意思?

这是我在学数字信号处理的笔记。

信号处理是分析一个过程,而这个过程是随时间变化的。分为2种:

  1. 模拟信号处理
  2. 数字信号处理

自然界的所有声音都是模拟的,在研究时通常需要转换成数字的,因为使用的处理工具都是数字的,毕竟电子产品都叫“digital products”,当然最开始也有“模拟计算机”,但慢慢就被时代淘汰了,为什么被淘汰,我也不是很清楚。

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