Biblio

Extracting knowledge from unstructured data silos, a legacy of old applications, is mandatory for improving the governance of today's cities and fostering the creation of smart cities. Texts in natural language often compose such data. Nevertheless, the inference of useful information from a linguistic-computational analysis of natural language data is an open challenge. In this paper, we propose a clustering method to analyze textual data employing the unsupervised machine learning algorithms k-means and hierarchical clustering. We assess different vector representation methods for text, similarity metrics, and the number of clusters that best matches the data. We evaluate the methods using a real database of a public record service of security occurrences. The results show that the k-means algorithm using Euclidean distance extracts non-trivial knowledge, reaching up to 93% accuracy in a set of test samples while identifying the 12 most prevalent occurrence patterns.

Blockchain has revolutionized supply chain system security, especially with Internet of Things integration. Deploying blockchain in the supply chain incorporates immutability, transparency, and traceability mechanisms that promote secure data sharing and interactions between stakeholders in trustless environments. A blockchain-based supply chain as a layered architecture consists of three main layers: supply chain, blockchain, and IoT. This type of system is safer and more transparent, with better traceability than traditional supply chain; however, the system faces several security issues. This paper briefly discusses the primary security challenges related to blockchain-based supply chain systems.

Digital communication platforms, such as Gmail and Yahoo, are become essential in our professional and personal lives. In addition to the low cost of e-mails, they are fast. Despite the advantages of these tools, spammers try to send unsolicited e-mail, known as spam, daily. Recently, image spam, a new type of spam e-mail, is developed by spammers in order to avoid detection based on text-based spam filtering systems. Image spam contains more complex information as compared to text spam. For this reason, the detection of image spam is still a challenging task for researchers. Most of the developed image spam filtering systems are based on hand-crafted features and machine learning techniques, which are time-consuming and less efficient. In addition, these systems do not focus on the important features, which can have an impact on the detection process. In this paper, we apply the convolutional block attention module (CBAM) model in order to address the problem of image spam. The experiments are conducted on the available dataset, called image spam hunter (ISH). The results obtained are then compared, using the CBAM model, to other existing state-of-the-art methods. The results obtained have demonstrated that the convolutional block attention module (CBAM) is efficient for image spam detection.

Due to the extensive use of network services and emerging security threats, enterprise networks deploy varieties of security devices for controlling resource access based on organizational security requirements. These requirements need fine-grained access control rules based on heterogeneous isolation patterns like access denial, trusted communication, and payload inspection. Organizations are also seeking for usable and optimal security configurations that can harden the network security within enterprise budget constraints. In order to design a security architecture, i.e., the distribution of security devices along with their security policies, that satisfies the organizational security requirements as well as the business constraints, it is required to analyze various alternative security architectures considering placements of network security devices in the network and the corresponding access controls. In this paper, we present an automated formal framework for synthesizing network security configurations. The main design alternatives include different kinds of isolation patterns for network traffic flows. The framework takes security requirements and business constraints along with the network topology as inputs. Then, it synthesizes cost-effective security configurations satisfying the constraints and provides placements of different security devices, optimally distributed in the network, according to the given network topology. In addition, we provide a hypothesis testing-based security architecture refinement mechanism that explores various security design alternatives using ConfigSynth and improves the security architecture by systematically increasing the security requirements. We demonstrate the execution of ConfigSynth and the refinement mechanism using case studies. Finally, we evaluate their scalability using simulated experiments.