Вип. 36

Постійний URI для цього зібранняhttps://repositary.knuba.edu.ua/handle/987654321/362

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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.
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 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.
Business model analysis of Meituan
(КНУБА, 2018) Yinglin Ji
In order to understand and analyze the business model of an enterprise, this paper selects Meituan as a case study. First of all, it introduces the general situation of the company. Secondly, the paper introduces the business model of the company in terms of profit model, key resources, main activities, value proposition and customer segmentation. Potter's five force model is used to analyze the competitive environment of the business model of Meituan. Finally, the advantages and disadvantages of analysis, put forward that the business model needs to focus on innovation, transformation, and creating brand influence.
Cloud computing workflow scheduling with maximum reduction of effective resources
(КНУБА, 2018) Xiaotian Liu; Daming Gu
In order to solve the problem that resource utilization efficiency of large-scale scientific workflow is low in cloud computing environment, this paper proposes an algorithm of maximum effective resource reduction (MERR). The algorithm is mainly implemented in three steps. First, identify the delay limitation, finding the balance between the reduction of effective resource use and the increase of time. Second, task merge and merge the tasks with low resource utilization in original workflow scheduling. The third is resource consolidation, a best fitting method is adopted to combine resources that are not fully used, so as to improve the efficiency of resource utilization. Using CyberShake, Epigenomics, LIGO and Montage four kinds of scientific workflow to carry out simulation experiments. The results show that MERR has reduced using resources by 54%, and the average time increase is less than 10%, which are better than scheduling algorithm based on the critical path.
Compare and analysis of detection algorithm of crop leaf area based on MATLAB software
(КНУБА, 2018) Chen Jie
Traditional edge detection operators belong to linear filtering methods. Mathematical morphology is a non-linear filtering method, which can maintain the basic shape characteristics of the image and is widely used in various fields of image processing. Only the edge detection operator or mathematical morphology processing can’t get ideal segmentation results. According to the results of edge operator detection, morphological filtering and mathematical morphological operation are carried out, and the edge information of plant leaves is extracted by repeated experiments with different structural elements. Based on MATLAB software, the image of plant leaf was analysed by the diffent mathod of Sobel, Prewitt, Canny, and Morphology. The result of Sobel mathod as the best one was chosen to be analysed by Denoising mathod. The last result was suitable for the image area algorithm.
Design and research on bending mould of high-strength plates
(КНУБА, 2018) Zhou Huan; Hui Weidong
CNC bending machine is a kind of molding pressure equipment, which is widely used in the process of sheet metal bending, it can press the sheet metal into different angles and different geometric shapes. Equipped with the corresponding industrial equipment, it can also achieve stretching, punching, such as corrugation processing technology. With the development of production technology, people become more and more pursue the quality. High-strength plate tensile strength and hardness is very high, When using a common mould for bending, would first destroy the mould and can't be bending. In this paper, the initial design of high-strength plate bending mold is carried out, the 3D model of each part of the mould is established, and the simulation analysis of the stress is carried out. The bending principle of the mould and the calculation formula of the bending force are introduced, has the very important economic significance for the reasonable selection of bending mould.
Determination of the biosphere compatible environment attractors of urbanized territories at the organization of modern construction development
(КНУБА, 2018) Chernyshev, Denys; Predun, Konstantyn; Ivakhnenko, Iryna; Druzhynin, Maxim; Ruchinskaya, Julia
The article considers current trends in ecological construction based on the principles of biosphere compatibility. The necessity of an integrated, multi-level approach to addressing the environmental safety of urbanized areas and the renovation of the urban environment is shown. The evolution of ecological-economic systems in the organization of biosphere-compatible construction can be interpreted as a sequential transition of the system from one attractor to the second through unstable chaotic states and sharp break points (bifurcation points). The article considers the issues of defining and specifying properties, conditions, evolution of ecological-economic systems as an object of management from the level of the national economy to an investment project. Generalized indicators of the biosphere compatibility of territories and the level of implementation of city functions are proposed, a method for calculating the components of the humanitarian balance is developed on the basis of a comprehensive analysis and the accepted concept of improving the environmental safety of construction sites. Further, the presented algorithm enables monitoring to form a phase portrait of an attractor of ecological-economic systems based on an assessment of biosphere compatibility indicators.
Development of the temperature and humidity intelligent control system for fig orchard based on rfid technology
(КНУБА, 2018) Luo Wenhua
For increasing the fig production and quality, and saving the labor cost, a kind of management fig garden intelligent system is designed combining the research on the fig tree cultivation situation and growth period. In this system the RFID tags which are equipped with sensors are installed on side of fig trees and will sense and save the temperature and humidity in Real Time mode. Data will be sent to a small Server trough the LAN from the Readers of RFIDS which are installed in different parts of the orchard. The Server will save the data and analyze them based on its software. If the humidity or temperature is not in a good condition, a tractor equipped with watering and poison tank, air conditioner and humidifier will be activated and sent to the tree. The intelligent gardening software system include tree guarding software(TGS) and path finding software(PFS). The TGS is installed on the Server, and investigates all data of each tree. If any tree needs watering or temperature change, it will indicate the amount and the type of the requirement. The server will send the information to the interfacing circuit and the tractor will receive the information, head to the tree and take the necessary steps. The PFS is also installed on the Server and receives the identification code of the nearest tag via the Reader which is connected to Server for recognize tractor coordinates. Then modified route base on inter database and identification code, finally move to the goal tree.
Intelligent brake design based on RBR and CBR hybrid reasoning
(КНУБА, 2018) Hui Weidong; Zhou Huan; Gu Qi
For intelligent design of a brake, different knowledge should be obtained effectively from the huge design knowledge sources.To improve efficiency of case-based reasoning in design of brake products and accurately reason the required optimal design proposal, by combining design characteristics of the brake, this paper proposes one CBR-RBR hybrid reasoning method by studying and analyzing brake design flow and field knowledge,by combining the phase hierarchical structure of product design, different reasoning mechanisms are used in the design of the brake proposal and specific parameterized design. The CBR is used to reason the design of brake proposal, structural type of specific type and selection of general deployment mode. RBR is used to reason the case adaptions of main structures, size parameters, structural models and materials used. The general structure design of the brake is used to explain the whole process.
Mechanical design of small vertical axis wind turbine
(КНУБА, 2018) Wang Bin
A new type of vertical shaft wind generator has a mechanical structure design, which can adjust the installation Angle of the wind blade according to the wind speed. When the wind force is large, the speed of the generator is higher than the rated speed. The blade Angle is adjusted by controlling the front and back movement of the electric push rod, so that the speed of the vertical shaft wind generator can be reduced to the rated speed. In this way, the stopping and fault of the wind generator caused by excessive speed can be avoided. At the same time, the braking system of the vertical shaft wind generator is designed, and the mechanical braking system is adopted.
Pipe line gravity heat pipe heat transfer numerical analysis research
(КНУБА, 2018) Xu Zhipeng; Wang Qisong
Gravity heat pipe is the most common type of heat pipe without core，it has the characteristics of simple structure, low cost, reliable work and high heat transfer efficiency. Waste heat recovery technology and comprehensive utilization of heat energy in various fields, the gravity heat pipe has reflected the unique superiority, according to the structure characteristics of the pipe line of gravity heat pipe, a mathematic model of the structure of the condenser. On the basis of mathematical model, through the preparation of the program C + + language, the numerical simulation study the communicating pipe type of gravity heat pipe heat transfer performance. A mathematical model is established according to the structural characteristics of the gravity heat pipe of the connected pipe row. Use FLUENT software for internal structure, to simulate the velocity vector according to the results of simulation analysis of pipeline of gravity heat pipe heat within the rationality of the steam and condensate return movement trend.
Research and design of raw silk evenness detector based on CCD image sensor
(КНУБА, 2018) Hu Yucai
In this paper, a dynamic measurement system of raw silk evenness based on machine vision is introduced. When the raw silk is moving at a certain speed by a drive device, the raw silk images are continuously captured by image acquisition system including a Charge Coupled Device (CCD) line sensor, a telecentric lens, a light source. To extract the main body of the raw silk accurately, the raw silk images are processed sequentially with threshold segmentation, morphological opening operation. And then the raw silk evenness is characterized by calculating the coefficient of variation (CV value) of diameter. Different image processing methods are discussed. When compared with the existing measurement and assessment of raw silk evenness, such as blackboard manual eye inspection and capacitance-detecting technology, the measurement method using machine vision has following characteristics. Firstly, because the image capture equipment is linear CCD with high resolution, the dynamical measurement of raw silk evenness can be realized with high speed. Secondly, the telecentric lens is adopted in the designed raw silk evenness measurement, which can eliminate the influence of the jitter of raw silk along the optical axis when image capturing. Finally, the high quality raw silk image can provide the information about raw silk after image threshold segmentation and morphology operation.
Research on modal characteristics of shanghai metro vehicle car body
(КНУБА, 2018) Tianjing Li
This article takes the head vehicle body of Shanghai Metro Line 13 as the research goal, through the finite element analysis of the vehicle body, to view the structural characteristics of various parts of the car body. First of all, look at the relevant parameters of the car body, analyze its structure, save some parts that have little effect on the results, reasonably simplify the car body structure, and use UG to draw a simplified 3D head car model. The model was imported into the finite element analysis software Hyper Mesh, which was divided into grids, defined materials, defined units, and unit-giving materials. The analysis order and analysis mode were determined, and the modal analysis of the vehicle body structure was performed to see the results of the modal analysis. The body vibration pattern and natural frequency under different orders are obtained. Analysis and statistics can provide the theoretical basis for the optimization and design of the body structure.
Risk management for an erp project
(КНУБА, 2018) Yinglin Ji
Risk management is the key step to ensure the successful implementation of ERP project. Thispaper mainly introduces the risk that the project may face, and the risk management steps that should be taken in the face of the risk. Next, the key steps of risk management are risk identification, risk assessment and risk control. Then combine the relevant theory with the implementation of the case for analysis.
The investigation of eutectic nucleation and growth mechanism of Al-Si alloy
(КНУБА, 2018) Anzhu Chen; Pengfei Zhou
Al-Si binary eutectic transformation, solidification occurred in the late eutectic (cell) crystal nucleation, eutectic nucleation and growth are a direct impact on formation of the defects of organizations (such as: shrinkage, thermal cracking, etc.) and the distribution of impurities elements and compounds, and so on .In this paper, analysis the microstructure of the alloy with modification by Sr, also thermal analysis was used to measure the unmodified alloys, EBSD was used to analysis the alloy with different status. The results showed that: The EBSD technique, whether or not modification, we observed that the eutectic nucleation on the primary dendrite and heterogeneity in inter-dendrites exist, and Sr has a significant effect on the primary α-Al, the primary α-Al phase in the AlSi10.5 alloy modified by 0.04% Al-10 wt. % Sr is more rounded and the size is much smaller than unmodified alloy. Fe has a great influence on the nucleation of eutectic Si.
The research and application on highlight line of curved surface quality evaluation based on 3D assembly environment
(КНУБА, 2018) Qi Gu; Nengjun Ben; Weidong Hui; Chao Wang; Mingxin Huang
In view of the present situation of quality analysis methods of curves and curved surfaces, the paper introduced the theoretical basis and mathematical expression of curves and curved surfaces. Four highlight line configuration types, such as reflection, projection, isocline, reflection contours, for evaluate the curves and curved surface quality had been studied in the 3D assembly environment. Finally, a comparative analysis of impeller base surface has been given by the four typesin a 3D impeller assembly.
Аналіз доцільності реалізації заходів щодо забезпечення інформаційної безпеки
(КНУБА, 2018) Гордієнко, Сергій Борисович; Манько, Олександр Олексійович; Манько, Володимир Олександрович; Скубак, Олександр Миколайович
Розглянуто деякі аспекти прийняття рішень щодо управління інформаційною безпекою. За основу аналізу і подальшого прийняття рішень розглянуто економічний аналіз, який передбачає вивчення всіх факторів, під впливом яких відбувається розвиток аналізованих систем, закономірностей їх поведінки, динаміки зміни, а також використання універсальної грошової оцінки. Складність завдань економічного аналізу практично у всіх сферах діяльності, як правило, обумовлюється тим, що багато ключових параметрів економічних моделей неможливо достовірно оцінити. Як основний критерій здебільшого використовують функцію віддачі від інвестицій (ROI). Незважаючи на складні розрахунки згідно цієї моделі, пропонована методологія дає змогу менеджерам та спеціалістам у сфері засобів захисту інформації отримувати достовірні результати і правильно оцінювати ефективність засобів захисту інформації, а також визначати напрям їхнього розвитку.
Аналіз математичного забезпечення інтелектуальних систем підтримки прийняття рішень з технічного регулювання в будівництві
(КНУБА, 2018) Ісаєнко, Дмитро Валерійович
Розглянуто питання розробки математичного забезпечення систем підтримки прийняття рішень з технічного регулювання в будівництві. Досліджено методи формального представлення задач експертного оцінювання. Детально описано задачі багатокритеріальної оптимізації та вибору найкращого об’єкта, які доцільно застосовувати в будівельній галузі на етапах передпроектної підготовки та планування будівельних робіт. Зокрема: наведено основні поняття, означення, теореми та положення, які необхідні для вибору методів та алгоритмів розв’язання задачі експертного оцінювання і розробки інтелектуальних систем підтримки прийняття експертних рішень у сфері технічного регулювання в будівництві. Визначено поняття ефективних об’єктів в сфері будівництва. Виконано формалізований опис математичних моделей різних ситуацій, в яких приймаються рішення з технічного регулювання в будівництві.
Аналіз особливостей проекту створення підприємства з обслуговування літаків в Еквадорі
(КНУБА, 2018) Сепеда Гуаман, Діего Фернандо
Повітряні судна є надскладними машинами, тому їх технічне обслуговування є складним і поділяється на чимало типів. Від складності обслуговування залежатиме і організація бізнесу з обслуговування повітряних суден, місце розташування такого підприємства, а також дозволи, які необхідно отримати. В Еквадорі представлені державні та приватні підприємства, причому державні підприємства мають кращий рівень технічного персоналу та ширший перелік технічних сертифікатів, які дають їм змогу обслуговувати більшу кількість (за моделями) повітряних суден. Відсутність належного обслуговування може призводити до серйозного негативного впливу на бізнесову діяльність авіакомпанії, яка володіє чи користується літаком, наданим у лізинг. Структура підприємства з обслуговування літаків визначатиметься, серед іншого, видом обслуговування літаків. Це може бути окремий підрозділ в рамках аеропорту, окреме підприємство або підрозділ заводу-виробника. Тож перед підприємством, що надає послуги з обслуговування літаків, стоятимуть ризики управління персоналом та високий рівень контролю над здійсненими роботами з обслуговування.