Algorithmic approach of destabilizing factors of improving the technical systems efficiency

In work, the questions of stabilization of factors of reliability of operation of the ship equipment are considered. According to the Navy Register rules, ship electrical power system voltage fluctuations within ±10 % of the nominal voltage are admissible if not lasting longer than 5 seconds; longer fluctuations are admissible if they are within ±5 % of the nominal voltage. The work of the engine with loads is presented. The algorithm for parameter optimization was applied. The calculation is performed on real parameters

The use of fuzzy control methods for evaluation of complex systems on the example of maritime fleet equipment

At present, the interest in application of synchronous machines in the various systems of the electric drive and energy sources is still growing. Synchronous motors and their modifications enable to develop low-noise, reliable and economically efficient electric drive systems. They provide high maneuverability when using a propeller power plant of the submersible vehicles and the World fleet vessels. Synchronous generators are the major energy sources in the electric power systems of the variety autonomous plants: on vessels, offshore and coastal oil rigs, etc

CSIKE-ENC Combined Encryption Scheme with Optimized Degrees of Isogeny Distribution

For the PQC CSIDH and CSIKE algorithms, the advantages of two classes of quadratic and twisted supersingular Edwards curves over complete Edwards curves are justified. These classes form pairs of quadratic twist curves with order p + 1 ≡ 0mod8 over the prime field Fp and double the space of all curves in the algorithms. The randomized algorithms CSIDH and CSIKE are presented. An analysis of the degrees lk isogenies distribution is given, and an optimal distribution within the given conditions is proposed with the degree lmax = 397 instead of lmax = 587 while maintaining the number K = 74 of all degrees. A probabilistic analysis of random odd order points R was carried out, probability estimates are obtained, and it is recommended to avoid isogenies with small values of the degrees lk in algorithms. The features of the CSIKE algorithm with one public key of Bob in the problem of encapsulation by Alice of the secret key κ, which Bob calculates at the stage of decapsulation with his secret key, are considered. A CSIKE-ENC scheme for combined encryption of the key κ and message M based on two asymmetric algorithms CSIDH and CSIKE with Alice’s authentication and the well-known symmetric message encryption standard is proposed. The security aspects of the scheme are discussed

Lead candidates for high-performance organic photovoltaics from high-throughput quantum chemistry – the Harvard Clean Energy Project

The virtual high-throughput screening framework of the Harvard Clean Energy Project allows for the computational assessment of candidate structures for organic electronic materials – in particular photovoltaics – at an unprecedented scale. We report the most promising compounds that have emerged after studying 2.3 million molecular motifs by means of 150 million density functional theory calculations. Our top candidates are analyzed with respect to their structural makeup in order to identify important building blocks and extract design rules for efficient materials. An online database of the results is made available to the community.Engineering and Applied Science

Biological Earth observation with animal sensors

Space-based tracking technology using low-cost miniature tags is now delivering data on fine-scale animal movement at near-global scale. Linked with remotely sensed environmental data, this offers a biological lens on habitat integrity and connectivity for conservation and human health; a global network of animal sentinels of environmen-tal change

Дослідження напружено–деформованого стану елементів палуби контейнеровоза з використанням системи диференційних рівнянь Кармана

The current stage of development of the shipbuilding industry is characterized by the emergence of new types of ships, structurally significantly different from the traditional ones. In this connection, it is necessary to build more rigorous physical models describing the behavior of ship structures under the action of external loads.Structural mechanics of the ship, as an independent science, began to form at the beginning of the XX century. The founder of this science according to the rule can be considered a Russian scientist and shipbuilder, professor of the Naval Academy and the shipbuilding department of Petrograd Polytechnic Institute. Based on previous knowledge of the theory of elasticity to them the first rules of allowable stresses have been proposed for surface ships, the methods for evaluating the strength and stability of ship floors and reinforced plates were developed.Currently, structural mechanics of the ship faces a number of problems requiring urgent solutions, such as the desire for maximum reduction of body materials consumption, the emergence of new, more advanced manufacturing processes of the hull. To solve these problems, it is necessary to turn to the theoretical research and use the knowledge gained during the last three centuries, various scientists involved in various developments in the science of strength of materials, theory of elasticity, and theory of plasticity and structural mechanics of the ship.The importance of building effective and reliable calculation methods to predict the impact of the loading process on the long–term strength of structural materials is caused by the need to ensure long–term durability of structures in the conditions of insufficient and costly experimental studies.Container shipping today is the most convenient and the most universal means of transportation. A wide variety of types of containers (dry cargo, refrigerated, insulated, flat track, tank containers) ensures not only fast loading and unloading, but also the opportunity to use the maximum vessel capacity.The software system was studied and defined, which allows determining the deformation of the upper deck of the ship while loading and on the resulting chart voltages to determine possible locations of damage with the aim of preventing them, because any accident on the ship can not only cause human and material losses, but also major environmental disasters.The practical value of the results of the work lies in the fact that these studies make it possible to assess the actual loading of shipbuilding structures in terms of their operation.Рассматриваются современные методы и средства решения задачи расчета напряженно–деформированного состояния палубных элементов судов. Проведен анализ современных методов оценки напряженно–деформированного состояния судовых пластин на стадии проектирования и эксплуатации судна. Для этого в качестве обзора рассмотрены основные программные комплексы, позволяющие проводить подобные расчеты, их положительные и отрицательные стороны. Приведены основные этапы создания программного обеспечения для проведения расчетов, основанных на использовании системы Кармана.Розглядаються сучасні методи і засоби вирішення задачі розрахунку напружено–деформованого стану палубних елементів суден. Проведено аналіз сучасних методів оцінки напружено–деформованого стану суднових пластин на стадії проектування і експлуатації судна. Для цього в якості огляду розглянуті основні програмні комплекси, що дозволяють проводити подібні розрахунки, їх позитивні і негативні сторони. Наведені основні етапи створення програмного забезпечення для проведення розрахунків, заснованих на використанні системи Кармана

Automation of intraoperative analysis of indicators the inflammatory response of neurosurgical patients undergoing brain tumors removal

The data of the study of indicators of the inflammatory response, hormonal status, biochemical blood parameters in the perioperative period in neurosurgical patients undergoing surgery for tumors of the posterior cranial fossa are presented. This study included 65 patients. The surgery was performed under anesthesia with fentanyl (3-5 µg / kg-hour), clonidine (1-2 µg / kg-hour), and propofol (3-5 mg / kg-hour). A significant increase in the level of interleukin 10 was observed at the level of hemostasis. The day after surgery, the level of Interleukin 6 increased significantly. During hemostasis, there was a temporary increase in ACTH, cortisol, and prolactin levels. The day after the surgery, rates returned to their original levels. Under conditions of persistent neurovegetative, a sufficient humoral response to surgical trauma was noted

Some problem of centrifugal compressors upgrading

The results of computational investigation of the influence of a gas labyrinth seals, oil end seals with floating rings and oil journal bearings lubricating layer stiffness coefficient on centrifugal compressor rotor critical speed are presented and analysed. The main principles of a method for axial forces acting on centrifugal compressor rotor calculation are listed. The method has been developed at the compressor, vacuum and refrigeration technologies department of SPbSTU. In addition, the estimation of method applicability in engineering calculations is given

ИсслЕдованиЕ напряженнО–дефОрмирОваннОгО состоЯниЯ элементоВ палубЫ контейнеровозА С использованиеМ системЫ дифференциальныХ уравнениЙ КАрмАнА

Рассматриваются современные методы и средства решения задачи расчета напряженно–деформированного состояния палубных элементов судов. Проведен анализ современных методов оценки напряженно–деформированного состояния судовых пластин на стадии проектирования и эксплуатации судна. Для этого в качестве обзора рассмотрены основные программные комплексы, позволяющие проводить подобные расчеты, их положительные и отрицательные стороны. Приведены основные этапы создания программного обеспечения для проведения расчетов, основанных на использовании системы Кармана