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2022-07-05
Sun, Lanxin, Dai, JunBo, Shen, Xunbing.  2021.  Facial emotion recognition based on LDA and Facial Landmark Detection. 2021 2nd International Conference on Artificial Intelligence and Education (ICAIE). :64—67.
Emotion recognition in the field of human-computer interaction refers to that the computer has the corresponding perceptual ability to predict the emotional state of human beings in advance by observing human expressions, behaviors and emotions, so as to ensure that computers can communicate emotionally with humans. The main research work of this paper is to extract facial image features by using Linear Discriminant Analysis (LDA) and Facial Landmark Detection after grayscale processing and cropping, and then compare the accuracy after emotion recognition and classification to determine which feature extraction method is more effective. The test results show that the accuracy rate of emotion recognition in face images can reach 73.9% by using LDA method, and 84.5% by using Facial Landmark Detection method. Therefore, facial landmarks can be used to identify emotion in face images more accurately.
2019-03-15
Deliu, I., Leichter, C., Franke, K..  2018.  Collecting Cyber Threat Intelligence from Hacker Forums via a Two-Stage, Hybrid Process Using Support Vector Machines and Latent Dirichlet Allocation. 2018 IEEE International Conference on Big Data (Big Data). :5008-5013.

Traditional security controls, such as firewalls, anti-virus and IDS, are ill-equipped to help IT security and response teams keep pace with the rapid evolution of the cyber threat landscape. Cyber Threat Intelligence (CTI) can help remediate this problem by exploiting non-traditional information sources, such as hacker forums and "dark-web" social platforms. Security and response teams can use the collected intelligence to identify emerging threats. Unfortunately, when manual analysis is used to extract CTI from non-traditional sources, it is a time consuming, error-prone and resource intensive process. We address these issues by using a hybrid Machine Learning model that automatically searches through hacker forum posts, identifies the posts that are most relevant to cyber security and then clusters the relevant posts into estimations of the topics that the hackers are discussing. The first (identification) stage uses Support Vector Machines and the second (clustering) stage uses Latent Dirichlet Allocation. We tested our model, using data from an actual hacker forum, to automatically extract information about various threats such as leaked credentials, malicious proxy servers, malware that evades AV detection, etc. The results demonstrate our method is an effective means for quickly extracting relevant and actionable intelligence that can be integrated with traditional security controls to increase their effectiveness.

2018-02-06
Zhang, Y., Mao, W., Zeng, D..  2017.  Topic Evolution Modeling in Social Media Short Texts Based on Recurrent Semantic Dependent CRP. 2017 IEEE International Conference on Intelligence and Security Informatics (ISI). :119–124.

Social media has become an important platform for people to express opinions, share information and communicate with others. Detecting and tracking topics from social media can help people grasp essential information and facilitate many security-related applications. As social media texts are usually short, traditional topic evolution models built based on LDA or HDP often suffer from the data sparsity problem. Recently proposed topic evolution models are more suitable for short texts, but they need to manually specify topic number which is fixed during different time period. To address these issues, in this paper, we propose a nonparametric topic evolution model for social media short texts. We first propose the recurrent semantic dependent Chinese restaurant process (rsdCRP), which is a nonparametric process incorporating word embeddings to capture semantic similarity information. Then we combine rsdCRP with word co-occurrence modeling and build our short-text oriented topic evolution model sdTEM. We carry out experimental studies on Twitter dataset. The results demonstrate the effectiveness of our method to monitor social media topic evolution compared to the baseline methods.

2017-03-08
Mishra, A., Kumar, K., Rai, S. N., Mittal, V. K..  2015.  Multi-stage face recognition for biometric access. 2015 Annual IEEE India Conference (INDICON). :1–6.

Protecting the privacy of user-identification data is fundamental to protect the information systems from attacks and vulnerabilities. Providing access to such data only to the limited and legitimate users is the key motivation for `Biometrics'. In `Biometric Systems' confirming a user's claim of his/her identity reliably, is more important than focusing on `what he/she really possesses' or `what he/she remembers'. In this paper the use of face image for biometric access is proposed using two multistage face recognition algorithms that employ biometric facial features to validate the user's claim. The proposed algorithms use standard algorithms and classifiers such as EigenFaces, PCA and LDA in stages. Performance evaluation of both proposed algorithms is carried out using two standard datasets, the Extended Yale database and AT&T database. Results using the proposed multi-stage algorithms are better than those using other standard algorithms. Current limitations and possible applications of the proposed algorithms are also discussed along, with further scope of making these robust to pose, illumination and noise variations.