RESUMEN

The authority of user personal health records (PHRs) is usually determined by the owner of a cloud computing system. When a PHR file is accessed, a dynamic access control algorithm must be used to authenticate the users. The proposed dynamic access control algorithm is based on a novel Lagrange interpolation polynomial with timestamps, mainly functioning to authenticate the users with key information. Moreover, the inclusion of timestamps allows user access within an approved time slot to enhance the security of the healthcare cloud system. According to the security analysis results, this healthcare cloud system can effectively resist common attacks, including external attacks, internal attacks, collaborative attacks and equation-based attacks. Furthermore, the overall computational complexity of establishing and updating the polynomials is O(n*m* (log m)2), which is a promising result, where m denotes the degree of $ polynomial~G\left(x, y\right) $ and n denotes the number of secure users in the hierarchy.

Asunto(s)

Seguridad Computacional , Confidencialidad , Algoritmos , Nube Computacional , Atención a la Salud

RESUMEN

According to the educational regulations in Taiwan, students are required to learn English when they are at the first grade of elementary school. However, not all the students have an appropriate environment to practice English, especially, for those students whose school is not located in the city. Thus, their English abilities in speaking, reading, and listening are poor. An intelligent tutoring system is used to help the students improve their English capabilities. This paper aims to provide a convenient tutoring environment, where teachers and students do not need to prepare a lot of teaching aids. They can teach and learn English whenever in the environment. Also, it proposes a method to verify the intelligent tutoring system using Petri nets. We have built the intelligent tutoring system based on Augmented Reality (AR), Text-to-Speech (TTS), and Speech Recognition (SR). This intelligent tutoring system is divided into two parts: one for teachers and the other for students. The experimental results have indicated that using Petri nets can help users verify the intelligent tutoring system for better learning performance and operate it correctly.