فاطمه عظیم زاده

The Internet of Things (IoT) has become increasingly prevalent, and recent advances in machine learning, particularly in healthcare, have gained significant attention from researchers. One prominent interdisciplinary topic in these fields is human activity recognition (HAR). Despite extensive research, several challenges remain in this area, especially concerning the application of modern machine learning techniques for HAR. This study proposes a novel method for human activity recognition by combining radial basis function neural networks (RBFNN) and support vector machines (SVM). The approach enhances recognition accuracy and algorithm efficiency by extracting relevant features using RBFNN and convolutional neural networks (CNN). Classification is then performed using SVM. The proposed method was evaluated using the UCI HAR dataset, which includes six distinct human activities. Results demonstrate that the proposed approach achieves an accuracy of 99%, surpassing existing methods.

The surge in internet usage has sparked new demands. Historically, specialized web crawlers were devised to retrieve pages pertaining to specific subjects. However, contemporary needs such as event identification and extraction have gained significance. Conventional web crawlers prove inadequate for these tasks, necessitating exploration of novel techniques for event identification, extraction, and utilization. This study presents an innovative approach for detecting and extracting events using the Whale Optimization Algorithm (WOA) for feature extraction and classification. By integrating this method with machine learning algorithms, the proposed technique exhibits improvements in experiments, including decreased execution time and enhancements in metrics such as Root Mean Square Error (RMSE) and accuracy score. Comparative analysis reveals that the proposed method outperformed alternative models. Nevertheless, when tested across various data models and datasets, the WOA model consistently demonstrated superior performance, albeit exhibiting reduced evaluation metrics for Wikipedia text data.

The diversity and high volume of available information on the web make data retrieval a serious challenge in this environment. On the other hand, obtaining user satisfaction is difficult, which is one of the main challenges of data retrieval systems. Depending on their information about interests and needs for the same keyword, different people expect different responses from Information Retrieval (IR) systems. Achieving this goal requires an effective method to retrieve information. Personalized Information Retrieval (PIR) is an effective method to achieve this goal which is considered by researchers today.  Folksonomy is the process that allows users to tag in a specific domain of information in a social environment (tags are accessible to other users). Folksonomy systems are made collaborative tagging systems. Due to the large volume and variety of tags produced, resolving ambiguity is a severe challenge in these systems. In recent years, word embedding methods have been considered by researchers as a successful method to fix the ambiguity of texts. This study proposes a model which, in addition to using word embedding methods to remove tag ambiguity, provides search results in a personalized approach by fixing ambiguity and sentiment analysis combination tailored to users' interests. In this research, different models of word embeddings were applied. The experiments' results show that after applying the fixing ambiguity, the mean accuracy criterion improved by 1.93% and the mean MRR ( Mean Reciprocal Rank)  by 0.38%.