Development of dynamic protection against timing channels

Information systems face many threats, such as covert channels, which declassify hidden information by, e.g., analyzing the program execution time. Such threats exist at various stages of the execution of instructions. Even if software developers are able to neutralize these threats in source code, new attack vectors can arise in compiler-generated machine code from these representations. Existing approaches for preventing vulnerabilities have numerous restrictions related to both their functionality and the range of threats that can be found and removed. This study presents a technique for removing threats and generating safer code using dynamic compilation in an execution environment by combining information from program analysis of the malicious code and re-compiling such code to run securely. The proposed approach stores summary information in the form of rules that can be shared among analyses. The annotations enable us to conduct the analyses to mitigate threats. Developers can update the analyses and control the volume of resources that are allocated to perform these analyses by changing the precision. The authors’ experiments show that the binary code created by applying the suggested method is of high quality.     

The General Explanation Method with NMR Spectroscopy Enables the Identification of Metabolite Profiles Specific for Normal and Tumor Cell Lines

Machine learning models in metabolomics, despite their great prediction accuracy, are still not widely adopted owing to the lack of an efficient explanation for their predictions. In this study, we propose the use of the general explanation method to explain the predictions of a machine learning model to gain detailed insight into metabolic differences between biological systems. The method was tested on a dataset of ¹H NMR spectra acquired on normal lung and mesothelial cell lines and their tumor counterparts. Initially, the random forests and artificial neural network models were applied to the dataset, and excellent prediction accuracy was achieved. The predictions of the models were explained with the general explanation method, which enabled identification of discriminating metabolic concentration differences between individual cell lines and enabled the construction of their specific metabolic concentration profiles. This intuitive and robust method holds great promise for in‐depth understanding of the mechanisms that underline phenotypes as well as for biomarker discovery in complex diseases.     

Effect of process parameters of manufacturing of composite fibrous membranes on their structure and ion selectivity

The porous structure of Polikon K composite ion-exchange membranes based on polyacrylonitrile fibers has been studied by standard contact porosimetry. Differences in maximum porosity, internal specific surface area, macropore volume, and other structural characteristics attributed to the use of different molding pressures during the preparation of the membranes have been revealed. According to the analysis of the porometric curves measured in octane and water, it has been found that the volume of hydrophobic pores in the Polikon membranes is an order of magnitude lower than the total volume of hydrophilic pores. The ion selectivity of the membrane materials has been estimated from the porometric curves. A comparison of the ion transport numbers measured by the potentiometric method to the calculated values has shown that they are in good agreement.     

Multi-level association rules and directed graphs for spatial data analysis

We propose a methodology that upgrades the methods of the Lagrangian analysis of surface sea-water parcels. This methodology includes data mining with efficient visualization techniques, namely, spatial–temporal association rules and multi-level directed graphs with different levels of space and time granularity. In the resulting multi-level directed graphs we can intertwine knowledge from various disciplines related to oceanography (in our application) and perform the mining of such graphs. We evaluate the proposed methodology on Lagrangian tracking of virtual particles in the velocity field of the numerical model called the Mediterranean Ocean Forecasting Model (MFS). We describe an efficient algorithm based on label propagation clustering, which finds cycles and paths in multi-level directed graphs and reveals how the number and size of the cycles depend on the seasons. In addition, we offer three interesting results of the visualization and mining of such graphs, that is, the 12 months periodicity of the exchange of water masses among sea areas, the separation of Mediterranean Sea circulation in summer and winter situations, obtained with the hierarchical clustering of multi-level directed graphs, and finally, with visualization with multi-level directed graphs we confirm the reversal of sea circulation in the Ionian Sea over the last decades. The aforementioned results received a very favorable evaluation from oceanographic experts.     

Vector optimization of a dynamic standard-size product series

A model and an algorithm of optimization of a standard-size product series on the basis of a two-criterion statement are described and their use for the determination of rational types of trucks in Ukraine is considered. Translated from Kibernetika i Sistemnyi Analiz, No. 2, pp. 157–163, March–April, 2000.     

Composite materials based on polyester resin and chemical fibres

The essential role of the strength, textile structure, and compatibility of reinforcing chemical fibres with the polymer binder in formation of the structure and properties of composite materials based on polyester resin was demonstrated. Technical documentation was developed for fabrication of polyester prepregs reinforced with chemical fibres and their processing into articles by compression molding. Translated from Khimicheskie Volokna, No. 4, pp. 20–22, July–August, 1998.     

The use of the Multi-Tabs vitamin and mineral complex to prevent influenza

Two cases of small bowel tumour, resected and considered as benign leiomyomas, are reported. Both developed late hepatic metastases, 6 and 8 years after surgery respectively, diagnosed as leiomyosarcoma. Emphasizing the difficulties in assessing malignancy of these tumours and considering local and far dissemination, a long-term follow-up is recommended after surgical resection.     

Submillimeter Laser Interferometer-Polarimeter for Plasma Diagnostics

The testing results of a homodyne 0.195-mm laser interferometer-polarimeter based on quasioptical components are presented. The interferometer-polarimeter matched to the multichannel interferometer of a Tokamak-15 machine admits of simultaneous measurements of the plasma electron density and poloidal magnetic field in one of the seven vertical-probing channels without any disturbance in the others. The achieved responce threshold of the electron density is 3.4·10¹¹ cm^?3, the polarization resolution and the phase difference measurement error are no worse than 0,1⁰ and ±4⁰, respectively.     

Reconstructing the parameters of cluster breakup of light nuclei

Kinematics of two-body Coulomb breakup of a prototype ¹¹B nucleus into ⁴He and ⁷Li fragments is considered. The factors affecting the accuracy in measuring the breakup parameters are analyzed, and the corrections having an influence on the accuracy in reconstructing the primary parameters of the cluster breakup are estimated. A method for estimating the effect of an unknown contamination in the target and the use of this method for separating true and background events are discussed. The influence of background factors occurring in heavy ion fragmentation reactions is analyzed, and random coincidences due to high background fluxes of parasitic products are estimated. It is proposed to use magnetic analysis of correlated breakup products to reduce the background particle flux and substantially (by several orders of magnitude) improve the accuracy in measuring the cluster energies.