Physics, mathematics, and technology

Physics, mathematics, and technology

Mathematics and computer science

Using CRM system to analyze the efficiency of bank employees

Abstract

The paper considers the possibility of using data collected by the CRM system for working with Bank clients to analyze the efficiency of Bank employees. An analysis of the CRM system functions was performed, from which about 20 attributes were obtained for forming the employee profile and by which it is possible to calculate its integral efficiency.

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Hybrid attack on Learning with Errors (LWE) with sparse secret

Abstract

In 2007, Howgrave-Graham proposed attack against NTRU cryptosys­tem, which consists of two parts, combining lattice reduction technique and a combinatorial method called meet-in-the-middle (MiTM). In this article, we apply hybrid attack to the Learning with Errors Problem (LWE) with sparse sec­ret. The LWE problem is considered to be one of the most important in lat­tice-based cryptography. Large number of cryprographic schemes ranging from basic signature and encryption schemes to advanced schemes like group sig­natures and fully homomorphic encryption, base their security on the hard­ness assumption of LWE. In this paper, we review the hybrid attack and the algorithms it is based on. It is required for further practical implementation of the attack, whose main objective is to verify correctness of MiTM to the hyb­rid attack against the LWE problem.

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Finding optimal BKZ parametrs for NTRU lattice reduction

Abstract

This article is devoted to selection of optimal parameters for lattice reduction attack against lattice-based cryptosystems that use lattices with low rank sublattices. It illustrates design flaws caused by current approach to buiding these types of cryptosystems. Its relevance and novelty lies in the description of the conditions for the existence of a polynomial attack and in constructing an efficient algorithm that allows us to find optimal reduction attack parameters. The algorithm developed during the work on this article is quite fast and requires O(log2n) log of time to return results where n is the dimension of lattice. Its correctness has been verified by numerical experiments. As a result, graphs are shown connecting the parameters of the lattice and the minimum smallest parameters necessary for its successful reduction.

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Secure sending of messages over the mesh network based on bluetooth

Abstract

In the paper we discuss the main problems that have to be solved to en­sure the confidentiality of communication between the nodes of mesh networks based on smartphones. We describe the important details of Bluetooth and Bluetooth Low Energy technologies, using which you can solve some of the problems described. Next, we briefly describe elliptic curve cryptography and choose a specific curve for it. We build an Elliptic Curve Integrated Encryp­tion Scheme based on the elliptic curves key exchange and various crypto primitives that allows exchanging protected information using symmetric en­cryption. We also describe the processes of encryption and decryption of mes­sages using this. As a result, the described technologies and the hybrid scheme are combined into the basic algorithm for secure data transmission over a mesh network based on Bluetooth, sufficient for software implementation.

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Scalable zk-SNARK

Abstract

This article describes the General principle of operation (stages, parame­ters used) of the ZK-SNARK zero-knowledge proof scheme, the possibility and prospects for its improvement. Implementations of zk-SNARK that are cur­rently known have scalability limitations that depend on the magnitude of the computation being proved. First, the size of the proving key depends at least linearly on the upper bound of the structure in which we work. Second, the proof requires a record of all previous steps. The article describes an algorithm for achieving a new implementation of zk-SNARK using elliptic curve cryp­tography, field structure features, and proof integrity. In practice, this imple­mentation is a recursive composition of the proof, while generating keys for any size of calculations carries constant memory costs. Subsequently, the en­tire process of proof is solely multiplicative constant costs overtime and addi­tivecosts in memory. Thus, the described implementation of zk-SNARK has two important properties: capacity and incremental computability.

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An efficient implementation of an exponential point-counting algorithm on Jacobians of genus 2 hyperelliptic curves

Abstract

Computing the order of Jacobian of a hyperelliptic curve is a common number-theoretical problem that has lots of applications in modern cryptog­raphy. Namely, Jacobians are applicable to constructions of DLP-based cryp­tosystems, as well as constructions of verifiable delay functions (VDF’s), since they can be viewed as large groups of unknown order. In this article, we pre­sent an overview of approaches to accelerate Gaudry-Schost point counting algorithm that is the fastest known algorithm for computing the order of Jaco­bians of hyperelliptic curves of genus 2. This algorithm consists of two stages: 1) computing the number of points (equivalently, the characteristic polynomi­al of the curve) modulo some small primes and combining the result into a large module using CRT (polynomial-time part); 2) restoring the number of points utilizing modular data using algorithms based on birthday paradox (exponential-time part). Theoretically, the algorithm terminates after the first stage with  time-complexity, where  is a finite field modulus. How­ever, in practice we terminate the polynomial-time part (due to high memory consumption), and we proceed to the second, memory-efficient, exponential-time part. This article presents a multithreaded C++ implementation of expo­nential part of Gaudry-Schost’s point counting algorithm. We evaluate the ef­ficiency of our multithreaded implementation.

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Theoretical and experimental physics

The research of the collective activity to overcome a diagnostic problem

Abstract

Currently, a number of diagnostic situations requiring consideration from the position of a council of physicians of the same (rarely) or different specialization is growing. Convening a council is often difficult or it is neces­sary to wait for a long time. Therefore, modeling mechanisms for solving of a diagnostic problems and its and cognitive visualization is relevant. The latter is also due to the fact that the safety of the made decisions depends on the speed of the doctor's response to the emerging problematic diagnostic situa­tion. The paper is dedicated to the research of the convening and group activi­ty of specialists within the council. Results of it would provide the basis of hy­brid functional intellectual systems with cognitive modeling of a diagnostic problem.

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Intellectualization of operational and technological control of regional electric power by cognitive hybrid intelligent systems. Part 1

Abstract

One of the most difficult task for an operator is the operational work with an image in intelligent complex dynamic control systems of a directly not per­ceptible object and projecting information from the outside onto this image. In this regard, the development of computer imitation of cognitive formations will lead to an increase in human intelligence in operational work, by supple­menting the operator's natural abilities to process operational and technologi­cal information by software and hardware (mechanisms) that expand human thought processes. This paper presents the results of the work of the first stage of the second year of the research on the topic of cognitive hybrid intelligent systems. Namely, results of the study of the operational and technological con­trol system of the regional electric power system, results of the categorization of the ontological semantics of the objective reality and the mathematical reali­ty of the object of technology operations activities.

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Model researches of a single-mirror antenna with a dual-band log-periodic irradiator directional properties in MathCAD

Abstract

The results of single-mirror antenna with a dual-band log-periodic irra­diator geometric parameters optimization and model researches of it’s range properties in MathCAD are presented in this article. The model of the mirror antenna radiation field used by the authors is based on the base of the surface currents method, the method of induced EMFs and theory of electric circuits with distributed parameters. The results of the research showed the adequacy of the constructed model and the compliance of the directional properties of the mirror antenna with the requirements imposed on them.

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Expansion of the arsenal of physical research methods of liquid dielectric examples exotic types of vegetable oils

Abstract

Research topic: the applicability of an external feature — electret-thermal analysis — to the study of liquid dielectrics, which are exotic types of edible vegetable oils.

The purpose of scientific research: to establish the relationship of the cur­rent response with heating of oil samples with their fatty acid composi­tion.

Description of the research methodology: for the analysis of samples of vegetable oils (pumpkin, walnuts, black cumin), the method of electret-thermal analysis, that is widely used in condensed matter physics, was ap­plied. When this method is implemented, during the heating of samples, a current response to the physicochemical changes occurring in them is rec­orded, which is compared with the fatty acid oils composition.

The main results, conclusions of the research work: based on the exist­ence of a non-zero current response, a hypothesis is put forward that ther­mally stimulated and accompanied by the flow of current destruction of un­stable supramolecular formations — associates of fatty acid triglycerides — occur in the samples. It has been established that the spectrum type of the thermally stimulated current is in obvious accordance with the fact which triglycerides of which specific fatty acids prevail in the composition of a par­ticular oil. A change in the current spectrum in comparison with the char­acteristic spectrum for this oil type can be considered a marker of damage or falsification.

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Features of connecting measuring devices with the software package Matlab

Abstract

The paper describes an algorithm for integrating digital measuring devic­es with a personal computer as part of a multifunctional instrument complex for using the resources of the Matlab application software package for record­ing and processing received signals. The basic device is a memory oscilloscope manufactured by «Tektronix», which has proven itself in laboratory experi­ments on radio spectroscopy. The proposed procedure for connecting the oscil­loscope to the software package is a sequence of actions that are quite accessi­ble to any user. At the same time, it can significantly increase the efficiency of using digital measuring devices in experimental technology.

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