Вибрані статті з наукових збірників

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3D кадастр, як інструмент регулювання майнових відносин у сфері землі та нерухомості
(КНУБА, 2016) Дубницька, М. В.; Крельштейн, П. Д.
Окреслена необхідність створення 3D кадастру як ефективного інструменту регулювання майнових відносин у сфері землі та нерухомості у великих містах. На прикладі конкретної земельної ділянки доведена ефективність оперування різними інтересами щодо неї в просторі, а не на площині.
3D моделювання Дністровського протипаводкового полігону
(ІТГІП, 2016) Зорін, Д. О.
Природними чинниками паводків є глобальне потепління, випадання великої кількості опадів за невеликі проміжки часу, що в 2–2,5 рази перевищує місячну норму, перенасиченість ґрунтів вологою (70–80%), складні рельєфні умови місцевості тощо. Антропогенні фактори також підвищують ризик розвитку катастрофічних наслідків паводків, це, зокрема, несанкціоновані розробки піщано-гравійної суміші, зменшення лісистості і розорювання схилів, внаслідок чого виникають або підсилюються ерозійні процеси, будівництво доріг, гідротехнічних споруд, поселенське й промислове будівництво, меліорація, розвиток туризму. Техногенне забруднення поверхневих вод шкідливими речовинами від потужних промислових підприємств також може виступати причиною розвитку паводків. Запропоновано 3D моделі розвитку паводків на Дністровському протипаводковому полігоні.
3D-реконструкция объектов с помощью беспилотных систем
(КНУБА, 2015) Кортунов, В. И.; Молчанов, А. А.; Гергель, И. А.
В статье представлены различные методы 3D-реконструкции объектов по снимкам стереосъемки или серии снимков, приведены преимущества и недостатки предложенных методов. Большое внимание в статье отведено факторам рассогласования стереокамер и методам их калибровки. Представлен также метод ускорения просчета карт глубины путем использования многопотоковости графического процессора, что позволит выполнять 3D-реконструкцию в режиме реального времени с помощью видеопотока
A 12-bit -channel pipeline ADC WITH 81 DB SFDR in 250 MS/s single0.13 UM CMOS
(КНУБА, 2018) Gu Jianhua; Yan Guojun; Ben Nengjun
A 12bit 250-MS/s pipeline ADC is presented and fabricated in 0.13um CMOS process. A power efficient bootstrap switch with a buffer is proposed for high speed considerations. It utilizes a source follower to insulate the residue amplifier and the large capacitor in the bootstrap switch. Techniques of lightening load capacitance of each stage are proposed to speed up the corresponding residue amplifiers (RA). A clock generator and optimized timing are proposed to achieve low jitter and improve sampling linearity by saving more time for the input switch. The reference buffer and clock buffer are both fully integrated. The signal-to-distortion-and-noise-ratio (SNDR) is evaluated adopting a proper scheme and verified by the measured results. The measured SNDR is 63 dB and spurious free dynamic range (SFDR) is 81dB with 39 MHz. The core area is 2 mm2 and the ADC consumes 160 mW at 1.3V.
A finite element technique and results of continual fracture process modeling
(KNUCA, 2014) Bazhenov, V.; Pyskunov, S.
The techniques of modeling of continual fracture process for space circular and prismatic bodies under long-term static or cyclic force loading condition and some results of determination of responsible parts lifetime is presented in this paper. The scalar damage parameter is used to describe the material continual fracture process. A stress-strain problem solution made with semianalytic finite element method (SFEM). It‘s shown , that the value of residual lifetime could be differ significantly for different loading condition and object configuration.
A method of determining the coordinates of the stiffness center and the stiffness principal axis of the vibrating system with damping
(КНУБА, 2014) Dang Xuan Truong; Tran Duc Chinh
The report presents a methodology to determine the directions of the stiffness principal axis (in this case subject to the linear displacement and forced rotation angle) of a solid object interact with the surrounding environment by resilient bearing supports. The results also show that determining the coordinates of the stiffness center in the vibrating system with damping factors is necessary in our research.
A methodology of determining of parameter j* in discrete models of finite element method
(КНУБА, 2017) Bazhenov, V. A.; Pyskunov, S. О.; Shkryl, О. О.
Based on the method of reactions, a technique for determining of the parameter J * by the method of subdomain moving in discrete models of finite element method (FEM) has been developed. A number of test problems solved. The obtained results confirm the effectiveness of the technique.
A new approach to the design of suspension roof systems
(КНУБА, 2020) Priadko, I. N.; Rudnieva I. N.; Ribakov, Y.; Bartolo H.
Over the last century, the suspension roofs design has progressed until the advent of the shells theory in the first half of the 20th century, due to a rapid pace in technological advancement. A paradigm shift emerged with the new trend in structural design towards a new design process that cooperatively integrated economy, efficiency, and elegance. Different approaches in computation, design and reliability assessment of roof structures are discussed in this work to identify the key conditions that have significantly contributed to modern suspension roof design principles. A new algorithm to assess the reliability of suspension roofs at the design stage is proposed and a novel method for computational design and reliability evaluation of suspension roofs is presented in this paper. This method enables to solve some topical issues, such as assignment of initial geometric roof parameters and relevant problems, like numerical determination of reliability indices for statistically non-determined systems of suspension roofs with a big cut on elliptical plan.
A new method of control of coherent structures in vortex apparatuses
(КНУБА : ІТГІП, 2018) Turick, Vladimir; Kochin, Viktor; Kochina, Mariia
A new method for direct control of energy-intensive coherent vortex structures (ECVS) in a vortex chamber is provided with stable vortex wires, which are descended from the lateral edges of a small elongated wing which is mounted in the inlet nozzle of the chamber. The main task is to determine the reaction of the ECVS in the dead-end ("passive") and the flow ("active") parts of the chamber to the control actions of the nozzle exciter is solved. The efficiency of the principle of mutual susceptibility of vortex structures on the processes of controlling coherent structures for bounded flows in the fields of centrifugal forces is experimentally proved. The observed phenomenon of "pumping" energy of pulsations from small vortices to larger ones allows it to be used to control aerodynamic and hydrodynamic processes of mixing and thermal processes in vortex process and energy devices.
A study on the speaker recognition algorithm based on Bayesian compressed sensing theory
(КНУБА, 2019) Yan Yang; Li Zhao
Speaker recognition technology is widely used in the Internet and communication filed. In recent years, compressed sensing theory attracted wide attention in and abroad. Having broken through the limitations of the Nyquist sampling rate, it can sampled compressible signals while compressing them at the same time.As a new theory, compressed sensing theory was brought into the filed of speaker recognition technology where huge breakthrough is in great demand to bring hope to enhance the performance of speaker recognition system. Aiming at the text independent speaker recognition technology, this paper made a profound study on the Bayesian compressed sensing algorithm. According to the characteristics of the sparse coefficient in the algorithm, a Gaussian prior assumption is introduced. And then a speaker recognition algorithm based on Bayesian compressed sensing is proposed.
Agile-трансформація підходів в управлінні будівельними проектами, фазах ініціації та проектування
(КНУБА, 2020) Бушуєв, С. Д.; Бушуєв, Д. А.; Бушуєва, В. Б.; Бойко, О. О.
Розглянуто моделі і методи побудови і впровадження інтеграції різних підходів до управління будівельними проектами та програмами. Проаналізовано поточний стан цілепокладання та визначення ефективних стратегій реалізації програм зі змінами напрямів стратегій розвитку в оточенні викликів, ризиків та можливостей. Стійкість розвитку будівельних проектів в умовах швидких і критичних змін зовнішнього та внутрішнього середовища може бути забезпечена ефективними моделями і методами цілепокладання і ціледосягнення в умовах критичних змін зовнішнього та внутрішнього середовища. Для управління будівельними проектами з урахуванням динаміки та адекватним реагуванням і забезпеченням компенсації змін в оточенні, менеджер інфраструктурної програми прогнозує тенденції розвитку оточення в короткостроковій і довгостроковій перспективі. Формулювання місії Agile-трансформації базується на концепції оцінки його цінності так, як це уявляє замовник, який дозволить заінтересованим сторонам здійснювати максимально продуктивну комунікацію і, за необхідності, погоджувати із замовником зміни і доповнення до інфраструктурної програми. Розглянуто контекстний аналіз як методологія осмислення і представлення цілісної картини будівельних проектів. Цей аналіз застосовується для інтерпретації місії та стратегії, якщо взаємодіючі численні цінності проекту виражені абстрактно. Невизначеність подібного типу спричиняє численні втрати і додаткові витрати.
Algorithmization tests development of spatial imagination
(KNUCA, 2015) Honta, Viktoria
In the article it is looked at the method algorithmization of chosen tests for development of spatial imagination, proposed combined algorithm for test of spatial imagination, shown schematic use of auxiliary algorithm. Setting further set of measures.
An analysis of raft thickness in high-rise buildings - case studies
(КНУБА, 2019) Nguyen Anh Tuan; Cao Van Hoa
This study shows that the raft thickness is depended on foundation system, Young modulus of soil right under the raft and number of floors of superstructure, and explains very well the case of thick raft of ICC Tower, thin raft of Dubai Tower and reasonable raft thickness of Incheon Tower.
An electronic device integrating linear and non-linear metering
(КНУБА, 2018) Sun Lixiang; Wang Chunmo
This paper designs an intelligent electronic metering device for the post office. Programs realize the non-linear relationship between the price and the weight of letters. The whole system is mainly composed of hardware and software. The hardware design uses STC89C52 MCU as the core control device of the system. MPX4115 pressure sensor collects the weight data and sends the output analog data to ADC0832. The converted digital data will be sent to the single chip microcomputer for data processing and the digital tube will display the data. The system is equipped with a matrix keyboard and four independent keys, which are used to select the delivery location (local port or foreign port), express delivery or letter type (ordinary or registered letter) and screen clearing function. The matrix keyboard is used to input the unit price. The prominent feature of this design is that it can not only realize the weighing of the weight and price of general merchandise in a linear relationship, but also realize the weighing of the weight and price in a non-linear relationship such as express delivery or letter. The design of the device can improve the deficiency of the electronic weighing system in application and has certain practical significance.
An estimation of residual lifetime of spatial structural elements under continual fracture condition
(КНУБА, 2014) Bazhenov, V. A.; Gulyar, O. I.; Pyskunov, S. O.
The techniques of modeling of continual fracture process for space circular and prismatic bodies under prolonged load condition and some results of determining of the estimated lifetime (up to local loss of material bearing capacity) and the residual (additional) lifetime (time of continual fracture zone growth) is presented in this paper. The Kachanov-Rabotnov’s scalar damage parameter to describe the continual fracture of the material and the semianalytic finite element method (SFEM) as numerical method of boudary problem solution is used. It‘s shown, that the value of residual lifetime could be differ significantly for different loading condition and object configuration.
An improved CARI algorithm based on sliding window in MIMO-OFDM system
(КНУБА, 2018) Zhang Hui; Xia Liling; Dong Rongwei; Wang Huihui
MIMO-OFDM is one of the core technologies in mobile communication system. As multicarrier modulation is adopted, the MIMO-OFDM system usually leads to high Peak-To-Average power ratio (PAPR), which can decrease the communication quality. The cross-antenna rotation and inversion (CARI) is an algorithm with better performance to reduce Peak-To-Average power ratio of MIMO-OFDM system. However, needing a large number of iterations is a shortage of CARI. The sub-optimal scheme of CARI – successive suboptimal CARI (SS-CARI) can reduce the number of iterations, but the PAPR reducing performance of it is lost largely. In view of this problem, a sub-optimal CARI method using sliding window to search for rotation and reverse combination is proposed in this paper. By using sliding window to search for the local optimal rotation and reverse combination, not only the overall traversal search can be avoided and the computational complexity of CARI algorithm can be reduced greatly, but also the PAPR reduction performance of SS-CARI can be improved. Simulation results show that a good trade-off between complexity of system and the PAPR reduction performance can be achieved by applying the proposed scheme.
An improved gradient-based method to solve parametric optimisation problems of the bar structures
(КНУБА, 2020) Peleshko I. D.; Yurchenko V. V.
The paper considers parametric optimisation problems for the bar structures formulated as nonlinear programming tasks. The method of the objective function gradient projection onto the active constraints surface with simultaneous correction of the constraints violations has been used to solve the parametric optimisation problem. Equivalent Householder transformations of the resolving equations of the method have been proposed. They increase numerical efficiency of the algorithm developed based on the method under consideration. Additionally, proposed improvement for the gradient-based method also consists of equivalent Givens transformations of the resolving equations. They ensure acceleration of the iterative searching process in the specified cases described by the paper due to decreasing the amount of calculations. The comparison of the optimisation results of truss structures presented by the paper confirms the validity of the optimum solutions obtained using proposed improvement of the gradient-based method. The efficiency of the propoced improvement of the gradient-based method has been also confirmed taking into account the number of iterations and absolute value of the maximum violation in the constraints.
Analysis of exploitation of residential five-storey buildings, erected on Zaporizhzhia's subsided grounds
(КНУБА, 2017) Shkoda, Victor; Syomchina, Maria; Shkoda, Andrei
This article gives an analysis of the housing stock Zaporizhzhia, shows the classification of residential buildings on the number of buildings storey and external walls material, considered types of deformations are given recommendations for improving the reliability of operation of five-storey residential buildings at their possible reconstruction. A significant part of Zaporizhzhia housing resources (about 25%) is made up of five-storey residential buildings, so-called "Khrushchovki", which were built according to standard design in the 50 − 60 years of the last century. The term of these buildings exploitation is coming to its critical deadline. The layout of such premises is morally obsolete and does not fit to live in. Besides, buildings of this class have sizeable physical wear be-cause of exploitation complexity on subsided soils. About fifth of old dwellings are deformed owing to subsidence of their foundations. The complex of protective measures, capable to provide required strength and operating buildings qualities in the cases of base soaking are absent.
Analysis of financing sources of projects development for Ukrainian enterprises
(КНУБА, 2017) Marchuk, Tetyana; Rуzhаkov, Dmуtrо; Bondarchuk, Natalya
In today's conditions of entrepreneurial development, the issue of energy efficiency improvement is important and urgent. Due to the constant volatility of energy prices, a high dependence on energy imports requires a large-scale energy reorientation of entrepreneurship. This article explores the world markets and trends in financing energy efficient projects. The current level and dynamics of energy intensity of GDP for the period of 2012-16 have been studied. A comparative characteristic of interest rates for loans and the size of «green tariffs» in the сase of energy saving in European countries and in Ukraine is carried out. The potential of the energy efficiency market in Ukraine by the types of energy, by the groups of the industrial sector and the population is presented. A detailed analysis of possible sources of financing of energy efficiency projects in Ukraine, both by international and national investors, has been carried out. The total level of the invested resources in energy efficiency projects is given.
Analysis of modified bitumen difference polymers
(KNUCA, 2014) Onischenko, A.; Kuzmіnets, M.; Aksenov, S.
An important step in the preparation of modified bitumen is selection of the composition and verification of various polymers’ effectiveness. Therefore, paddle mixers are widespread in both industrial and laboratory conditions for efficient mixing of bitumen with polymers. The developed method allows to determine the completion time of modification process at various process parameters (temperature, mixing speed and content of the modifier) to complete stabilization of the properties and the homogenization of bitumen. The results of studies showed that optimal time for bitumen modification at wich take place both stabilization of the properties and homogenization, ie astringent take the necessary level of uniformity with latex Butonal NS198, is about 3 hours.