AGH (Akademia Górniczo-Hutnicza) University of Science and Technology: Journals
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TOWARD RAM FORENSICS SUPPORTEDBY MACHINE-LEARNING METHODS
Full text linkIn this article, we propose an enhancement to the computer forensics technique of using Machine Learning tools to analyse the contents of RAM in order to extract information potentially useful during an investigation. In the specific case presented, the use of the extracted information to generate more optimal dictionaries for dictionary cryptanalysis is considered. Increasing user awareness is making cryptanalysis of passwords increasingly difficult for law enforcement. Long and complex passwords are impossible to crack, even when high-performance computing platforms are available. A sensible method of optimization is to look for hints to use a dictionary that contains text phrases more likely to be used in the specific case under attack. Such a hint could be an analysis of RAM taken from the suspect computer. Machine learning methods can significantly facilitate this task. In this article, we also explore the effectiveness of such an approach and its usefulness in practical applications. We also consider applications of the proposed approach for other purposes, such as OSINT
Hydrogeochemistry of brines on the example of selected water phenomena in the Kłodawa Salt Mine (central Poland)
Full text linkChemical and isotopic studies of brines in salt mines are a key element in identifying their origins. This, in turn, is applied in determining the degree of water hazard. Studies of the chemical and isotopic composition of eight brine samples in two measurement series were carried out at the Kłodawa Inc. Salt Mine in 2022 for pH, electrolytical conductivity of water (EC), mineral alkalinity, total alkalinity, total hardness, carbonate hardness, non-carbonate hardness, HCO3−, Ca2+, Mg2+, Na+, K+, Ba2+, Li+, Sr2+, NH4+, Cl−, SO42−, NO3−, NO2−, Br−, F−, I−, CO32− ions as well as δ18O and δ2H in H2O. Analysed water phenomena were selected based on archival data which indicated their various chemical compositions. Using analyses based on hydrochemical indices and isotopic composition, it was found that the studied brines represented the isotopic composition of O and H in H2O typical of Zechstein brines, Paleo-infiltration waters, pre-Pleistocene infiltration waters and waters of mixed origin. Their salinity was mainly primary (inherent) in nature. The dominant processes affecting chemical transformations were ion exchange, precipitation and dissolution of sulphate minerals and halite, redox processes and, to a lesser extent, mixing of waters. The possible influence of inclusions on water chemistry was also found. Additionally, the analysis showed limitations in the applicability of selected hydrochemical indices
A record of Eocene subaqueous large-scale mass movements in the external Tethys Ocean (Skyba Nappe, Outer Carpathians, Ukraine)
Full text linkStudies were carried out on the Popeli Beds, which were mainly deposited by mass movements along the northern slope of the Tethys Ocean and form an olistostrome sequence occurring within Paleogene deposits. The analysis focuses on the deposits exposed in the northern limb of the Pobuk Syncline – the structural element of the Oriv Skyba – in the external zones of the Skyba (Skole) Nappe. Structural, lithological, sedimentological and paleontological studies allowed for the identification and characterisation of the olistostrome sequence and revealed its structure. Six individual olistostrome complexes were distinguished and described in detail. Five of these are gravelly mudstones with oversized clasts, overlain by medium-bedded mudstones and sandstones, the last one consists of deformed packages of thin bedded mudstones and sandstones. The olistostrome sequence is composed of a wide range of lithological and stratigraphic components, including Tithonian – Berriasian shallowwater limestones (so-called Štramberk-type limestones), Upper Cretaceous limestones, sandstones, and siliceous rocks, as well as Paleogene mudstones, sandstones, limestones, and marls. Biostratigraphic analysis of foraminifera indicates the Bartonian as the time of displacement. The olistostrome niche migrated downslope from a lower shelf-upper slope position characterized by marl sedimentation, to slope areas dominated by turbidite sedimentation
Influence of the Addition of Tellurium and Heat Treatmenton the Microstructure of Hypoeutectic White Cast Iron
Full text linkThis study investigates how the addition of tellurium and heat treatment affects the microstructure of hypoeutectic white cast iron that has been modified with alloying elements such as titanium, chromium and vanadium. Samples with different chemical compositions were prepared and subjected to a two-step heat treatment process. Microstructural characterisation was performed using optical and scanning electron microscopy. The results show that introducing tellurium significantly affects the morphology of the cementite and carbide phases, causing them to fragment and become more evenly distributed. Furthermore, heat treatment enhanced matrix refinement and promoted phase stability. The combination of tellurium addition and heat treatment produced the most favourable microstructures, characterised by the high dispersion of hard phases within a fine-grained matrix
Circular raw material and waste management: a comparison of biological and chemical approaches for the recovery of metals from spent lithium-ion batteries
Full text linkModern production processes are characterized by the extensive demand for metal in the manufacture of lithium-ion batteries used in electronic equipment and electric vehicles. These products are essential for the functioning of today’s society, therefore, the demand for metallic raw materials increases annually, and their natural resources are overexploited. The solution to this issue is the recovery of raw materials from polymetallic waste, which includes spent lithium-ion batteries. The extraction of metals from this type of waste material has already been implemented on an industrial scale, but the priority now is to create technologies that will not only be effective in terms of metal recovery but also environmentally friendly, following sustainable development goals and the principles of a circular economy. Concerning the need for alternative ecological methods of waste processing, the concept of recovering Co, Cu, Li and Ni from waste lithium-ion batteries using a biotic and mild chemical approach was proposed. It has been determined that the biological approach to metal recovery may be a promising process in the recycling of lithium-ion battery waste since within 7 days, at a pulp density of 1% and using Acidithiobacillus thiooxidans bacteria, comparable results were obtained for the recovery of Co (25.7%), Li (48.8%) and Ni (28.3%) as for leaching with mild organic citric acid. Moreover, the fungus Aspergillus niger may be a promising microorganism used in the bioleaching of electrode powder from spent lithium-ion batteries, although the process using it requires the optimization of bioreactor parameters
Analysis of Hydrogen Gas Saturation in Sedimentary Sequences of Volyn-Podillya (Ukraine)
Full text linkWith the aim of using hydrogen energy by the Ukrainian industry, the paper considers the general patterns of hydrogen distribution in the sedimentary sequences of Volyn-Podillya. The general features of the distribution of water-dissolved and sorbed gases in rocks within productive and water-saturated complexes are analyzed. The genetic relationships between individual components of natural gases have been established, which allows us to identify depth intervals where hydrogen predominates in the well section. The latter, when used for regional forecasting, makes it possible to establish zones, and thus directions for the search for hydrogen accumulations in the sedimentary cover in Volyn-Podillya
Treextrust: topic-aware computational trust based on interaction experience, reputation of users with similarity and path algebra of graph in social networks
Full text linkTrust measure is confidence or reliability among users or peers and has been studied widely in online social networks. Most trust models currently are based on the concepts of interaction trust and reputation trust. However, various forms of interaction and analysis of interaction contexts have been not considered fully for trust estimation. Moreover, the mechanism for computing reputation trust based on propagation lacks a clear foundation and is expensive in computation. The purpose of this paper is to present a family of models of computational trust, named TreeXTrust, for estimating a trust degree of a user truster on another user trustee. Our model is a mathematical formulation based on aggregation of the topic-aware experience trust with various forms of interaction and the topic-aware reputation trust with users’ similarity and operators on path algebra in graph. We conduct experiments to evaluate how impact of interaction forms and users’ interests on experience trust and the correlation of experience trust and reputation trust on overall trust estimation. Our experimental results have demonstrated that: (i) Interest degrees influence on experience trust more than interaction ones; (ii) Community evaluation of some trustee affects the overall trust estimation more than the truster’s individual evaluation. Our family of models outperforms the state of art methods presented in the literature and is a framework for selecting and implementing a suitable model of computational trust for our problem at hand
Stable and low associative left-right hashing
Full text linkHashing is indispensable for efficient search operations, captivating the interest of numerous researchers. Among the diverse array of techniques, Cuckoo Hashing has emerged as particularly effective across a wide range of applications. It is implemented in two primary forms: Parallel Cuckoo Hashing and Sequential Cuckoo Hashing. Nonetheless, Cuckoo Hashing encounters significant challenges, including high insertion latency, inefficient memory usage, and high data migration costs. The concept of Combinatorial Hashing has inspired this research. Our proposed scheme enhances Combinatorial Hashing and introduces an innovative collision resolution technique called Left-Right Random Probing. This advanced variant of random probing strategically utilizes prime numbers and Fibonacci sequences to improve performance. This paper introduces two performance indicators, the degree of dexterity and table reference count per key. This paper identifies switching cost as a new challenge in Cuckoo Hashing and quantifies this switching cost using the parameter, table reference count per key
Information - Modern Theories
Full text linkThis review deviates from the usual approach to the topic of information by not focusing on Shannon’s Theory of Communication (TOC) and the related or derived concepts. In addition, we do not talk at length about information in relation to knowledge, data, communication, information processing, or similar concepts. Instead, we endeavor to reappraise our understanding of information without favoring any specific perspective. We know a lot about information, and the various conceptualizations of information presented in this paper are proof of this. Nevertheless, we also show that some lingering unresolved questions remain about the nature of information. To somewhat stem the appearance of further new concepts of information, we consider two perspectives, namely ontological and epistemic, and posit that we can potentially reduce all information variants to just these concepts. We then look at two general theories of information: the General Definition of Information (GDI) and the General Theory of Information (GTI), arguing that the GTI appears to be the better of these two options because it is more fundamental and comprehensive with deep metaphysical roots. Finally, we review some recent studies about information’s physical nature, such as for information and mass, meaningful physical information, and the persistence of information. This review, like all reviews, is selective and synthetic, but the extensive reference list provides the necessary resources to explore the discussed ideas in greater detail, as well as study the recent works on the nature of information