Статті в журналах: "Proportional machines"

1

Yin, Na, and Liying Kang. "Minimizing Makespan in Permutation Flow Shop Scheduling with Proportional Deterioration." Asia-Pacific Journal of Operational Research 32, no. 06 (December 2015): 1550050. http://dx.doi.org/10.1142/s0217595915500505.

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The [Formula: see text]-job and [Formula: see text]-machine permutation flow shop scheduling problem with a proportional deterioration is considered in which all machines process the jobs in the same order, i.e., a permutation schedule. A proportional deterioration means that the job deterioration as an increasing function that is proportional to a linear function of time. The objective is to minimize the makespan, i.e., the maximum completion time. When some dominant relationships between [Formula: see text] machines can be satisfied, we show that some special cases of the problem can be polynomial solvable. For the general case, we also propose a heuristic algorithm and give the computational experiments.

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2

Arkin, Esther M., and Robin O. Roundy. "Weighted-Tardiness Scheduling on Parallel Machines with Proportional Weights." Operations Research 39, no. 1 (February 1991): 64–81. http://dx.doi.org/10.1287/opre.39.1.64.

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3

Lemmink, Jacques. "‘Op proef doeltreffend gebleken, kunnen we spreken van een bereikt ideaal’." De Moderne Tijd 5, no. 1 (January 1, 2021): 35–59. http://dx.doi.org/10.5117/dmt2021.1.002.lemm.

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Abstract ‘Proved effective on trial, we can speak of an achieved ideal’ Abraham Kuyper and the mechanical voting machine, c. 1895-1905 During the latest presidential elections in the United States, unfounded conspiracy theories sprung up concerning alleged ballot box fraud by compromised voting machines. Although different voting machines had been used in the Netherlands since 1966, concerns over their reliability ended this in 2007. This article investigates the forgotten but ultimately failed attempt to introduce mechanical voting machines a century earlier. It focuses on the role played by prominent politician Abraham Kuyper, who personally visited the Standard Voting Machine Company in Rochester in 1898. The article illustrates how Kuyper’s transatlantic political and religious networks facilitated the voting machine’s transfer, rather than scientific connections. Paradoxically, the introduction of proportional representation in 1917 marked the end of tentative attempts to develop a Dutch version of the American mechanical voting machine. The implementation in the voting process turned out be too expensive, too early, and too complicated for the Dutch electoral system at the dawn of the twentieth century.

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4

Kaczmarczyk, Waldemar. "Proportional lot-sizing and scheduling problem with identical parallel machines." International Journal of Production Research 49, no. 9 (May 2011): 2605–23. http://dx.doi.org/10.1080/00207543.2010.532929.

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5

Wan, Yi, Qi Bo Cai, and Huan Wang. "The Research on Intelligent Control Method for EHP System." Advanced Materials Research 580 (October 2012): 12–15. http://dx.doi.org/10.4028/www.scientific.net/amr.580.12.

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Optimized machine learning algorithm is applied to control modeling of high-speed electric-hydraulic proportional system of high nonlinear in this paper, a identification model of high-speed electric-hydraulic proportional system is built based on support vector machines, fusion intelligent method of dynamic self-adaptive internal model control and predictive control is realized for high-speed electric-hydraulic proportional control system. Internal model and inverse controller model are online adjusted together. Simulation shows the satisfactory tracking effect by intelligent technology of dynamic self-adaptive internal control and predictive control based on the support vector machine, the dynamic characteristic is greatly improved by the intelligent control strategy for high-speed electric-hydraulic proportional control system, good tracking and control effect is reached in condition of high frequency response. It provides a new intelligent control method for high-speed electric-hydraulic proportional system.

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6

MATVEEV, Aleksey V. "Testing the Hypothesis about the Dependence of the Mass of Electric Machines on the Power and Speed." Elektrichestvo 7, no. 7 (2021): 4–18. http://dx.doi.org/10.24160//0013-5380-2021-7-4-18.

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The hypothesis stating that the mass of any rotating electric machine is proportional to its power capacity taken to a power of 0.75 and is inversely proportional to the square root of its rotation frequency is tested. The testing is carried out on the material of permanent magnet synchronous machines. The inﬂ uence of such factors as voltage, shape of active parts, cooling, eﬃ ciency level, overloads, presence of supporting structures, power supply frequency, and number of poles is studied. The hypothesis is tested by predicting the mass of machines in the widest possible range of power capacities (from 0.03 W to 36 MW) and rotation frequencies (from 2 to 500 000 rpm). The accuracy of the preliminary estimate of the machine mass within about 50% can be considered acceptable, given that the masses of the machines being estimated range from less than a gram to more than 100 t. Based on the study results, the formulation of a new law of electromechanics is proposed, which describes how the machine mass is predetermined in terms of its power capacity and rotation frequency. The ratio of machine power capacity taken to a power of 0.75 to the square root of its rotation frequency is to some extent similar to the “gravity” which the designers try to overcome working on weakening the eﬀ ect of the above-mentioned inﬂ uencing factors.

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7

MATVEEV, Aleksey V. "Testing the Hypothesis about the Dependence of the Mass of Electric Machines on the Power and Speed." Elektrichestvo, no. 7 (2021): 4–18. http://dx.doi.org/10.24160/0013-5380-2021-7-4-18.

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The hypothesis stating that the mass of any rotating electric machine is proportional to its power capacity taken to a power of 0.75 and is inversely proportional to the square root of its rotation frequency is tested. The testing is carried out on the material of permanent magnet synchronous machines. The inﬂ uence of such factors as voltage, shape of active parts, cooling, eﬃ ciency level, overloads, presence of supporting structures, power supply frequency, and number of poles is studied. The hypothesis is tested by predicting the mass of machines in the widest possible range of power capacities (from 0.03 W to 36 MW) and rotation frequencies (from 2 to 500 000 rpm). The accuracy of the preliminary estimate of the machine mass within about 50% can be considered acceptable, given that the masses of the machines being estimated range from less than a gram to more than 100 t. Based on the study results, the formulation of a new law of electromechanics is proposed, which describes how the machine mass is predetermined in terms of its power capacity and rotation frequency. The ratio of machine power capacity taken to a power of 0.75 to the square root of its rotation frequency is to some extent similar to the “gravity” which the designers try to overcome working on weakening the eﬀ ect of the above-mentioned inﬂ uencing factors.

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8

Ambrosimov, Sergey, Victor Meshcheryakov, and Igor Ivshyn. "Provision of High-efficient Milling Methods Using a PMSM Electric Drive with a Controlled Information-Measuring System." E3S Web of Conferences 178 (2020): 01025. http://dx.doi.org/10.1051/e3sconf/202017801025.

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The article presents new highly effective methods of milling shaped surfaces, which are implemented on four-and five-coordinate CNC machines. For their implementation, three simultaneously coordinated movements of the machine’s organs are used. To implement the proposed milling methods on CNC machines, an electric drive is proposed, built on the basis of a Permanent Magnet Synchronous Motor (PMSM) with a vector control system with a proportional P-speed controller. For this purpose, an ecstatic control information and measurement system with zero static error is proposed. Comparative results of mathematical modeling of transient processes in electric drives with the standard and proposed control systems are presented.

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9

Gomes, Robert R., Luiz F. Pugliese, Waner W. A. G. Silva, Clodualdo V. Sousa, Guilherme M. Rezende, and Fadul F. Rodor. "Speed Control with Indirect Field Orientation for Low Power Three-Phase Induction Machine with Squirrel Cage Rotor." Machines 9, no. 12 (November 27, 2021): 320. http://dx.doi.org/10.3390/machines9120320.

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Induction machines are widely used in the industry due to their many advantages compared to other industrial machines. This article presents the study and implementation of speed control applied to a Three-phase Induction Machine (MIT) of the squirrel cage type. The induction motor was modeled using the rotor flux in the synchronous reference to design Proportional-Integral (PI) type controllers for the current and velocity control loops. It is the objective of the article also to present in detail the development of converter hardware that comprises the stages of power, acquisition, and conditioning of engine signals. The system was simulated using computational tools and validated using a prototype designed, constructed, and commissioned.

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10

Ban, Branko, Stjepan Stipetic, and Tino Jercic. "Minimum Set of Rotor Parameters for Synchronous Reluctance Machine and Improved Optimization Convergence via Forced Rotor Barrier Feasibility." Energies 14, no. 10 (May 11, 2021): 2744. http://dx.doi.org/10.3390/en14102744.

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Although rare earth materials are the critical component in high torque density permanent magnet machines, their use has historically been a commercial risk. The alternatives that have been in the recent industry focus are synchronous reluctance machines (SyRM). They have lower torque density but also relatively low material cost and higher overload capability. Multi-layer IPM and SyRM machines have significant geometric complexity, resulting in a high number of parameters. Considering that modern machine design requires the use of optimization algorithms with computational load proportional to the number of parameters, the whole design process can take several days. This paper presents novel SyRM parameterization with reduced number of parameters. Furthermore, the paper introduces the novel forced feasibility concept, applied on rotor barrier parameters, resulting in improved optimization convergence with overall optimization time reduced by 12.3%. Proposed approaches were demonstrated using optimization procedure based on the existing differential evolution algorithm (DE) framework.

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11

Ma, Wei-Min, Li Sun, S. C. Liu, and T. H. Wu. "Parallel-Machine Scheduling with Delivery Times and Deteriorating Maintenance." Asia-Pacific Journal of Operational Research 32, no. 04 (July 23, 2015): 1550029. http://dx.doi.org/10.1142/s0217595915500293.

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In this paper, we consider parallel-machine scheduling with past-sequence-dependent (p-s-d) delivery times and deteriorating maintenance. The delivery time of a job is proportional to its waiting time in the system. Each machine has a deteriorating maintenance activity, i.e., delaying the maintenance increases the time required to perform it. We consider three versions of the problem to minimize the total absolute deviation of job completion times, the total load on all the machines, and the total completion time. We develop polynomial-time algorithms to solve them.

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12

Lawrence, Jason, William Singhose, and Keith Hekman. "Friction-Compensating Command Shaping for Vibration Reduction." Journal of Vibration and Acoustics 127, no. 4 (September 3, 2004): 307–14. http://dx.doi.org/10.1115/1.1924637.

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Fast and accurate point-to-point motion is a common operation for industrial machines, but vibration will frequently corrupt such motion. This paper develops commands that can move machines without vibration, even in the presence of Coulomb friction. Previous studies have shown that input shaping can be used on linear systems to produce point-to-point motion with no residual vibration. This paper extends command-shaping theory to nonlinear systems, specifically systems with Coulomb friction. This idea is applied to a PD-controlled mass with Coulomb friction to ground. The theoretical developments are experimentally verified on a solder cell machine. The results show that the new commands allow the proportional gain to be increased, resulting in reduced rise time, settling time, and steady-state error.

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13

De Soricellis, Milo, Davide Da Ru, and Silverio Bolognani. "A Robust Current Control Based on Proportional-Integral Observers for Permanent Magnet Synchronous Machines." IEEE Transactions on Industry Applications 54, no. 2 (March 2018): 1437–47. http://dx.doi.org/10.1109/tia.2017.2772171.

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14

PAPADOPOULOS, DEMETRIOS P. "Excitation controller design of synchronous machines with dynamic and proportional-plus-integral output feedback." International Journal of Systems Science 19, no. 10 (January 1988): 2091–101. http://dx.doi.org/10.1080/00207728808964101.

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15

Finkelstein, T. "A new isothermal theory for Stirling machine analysis and a volume optimization using the concept of ‘ancillary’ and ‘tidal’ domains." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science 212, no. 3 (March 1, 1998): 225–36. http://dx.doi.org/10.1243/0954406981521178.

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Theoretical studies of Stirling cycle machines have always utilized a topological system view that goes back to Schmidt's isothermal analysis, where the process is analysed by reference to the expansion space volume variations. Due to this idiosyncrasy in the formulation, it has been difficult to deduce meaningful design criteria from the results. In this paper an alternative visualization is presented, using the newly introduced concepts of a ‘tidal phase angle’ and overlapping ‘tidal’ and ‘ancillary’ domains. With vectorial parameters and a centralized reference basis, a non-dimensional parameter Rcaronfr;tcr, the ‘tidal compression ratio’, equal to the ratio of the average masses in the tidal and ancillary domains, is derived. This number uniquely characterizes the operation of equivalent machines and is therefore akin to the compression ratio in internal combustion engines. On the basis of this, a second new parametric grouping emerged to enhance the usefulness of the resultant integrated equations for use with dimensional analysis. It was defined as the ‘specific performance’ Rcaronfr;sp and is proportional to the output per unit mass, the gas constant and the operating temperature range. It is applicable to engines, heat pumps and refrigerators. Prior attempts at optimizing the proportions of a Stirling engine have not yielded usable results and consequently nearly all Stirling cycle machines built up to the present time have expansion and compression spaces of equal size. The new analysis shows that this is not the most appropriate configuration and it readily yields an optimization of the component volumes. One single analytical conditional equation for the optimum relative sizes of the constituent spaces was obtained from the new formulation for performance that quantifies the condition for an optimized proportioning of any Stirling cycle machine. It has three distinct usable solutions, one of which is an analytical confirmation of a postulate that has previously been published by the author without proof, equating VE/ VC and also Vh/ Vk to the temperature ratio TE/ TC. A numerical verification of this rule based on the proportions of the United Stirling V-160 engine compares it with 12 equivalent re-proportioned derivative engines, all with equal charge masses and operating at precisely the same conditions. This shows a substantial increase in the ideal performance through the use of the derived criteria. The main conclusion is that this theory may lead to a re-examination of the overall layout of Stirling cycle machines and the emergence of a new class of machines with superior performance.

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16

Avsiyevich, Andrei, Maksim Masalski, and Aliaksandr Shashko. "The Creation of Mechatronic Recovery Energy System for Mobile Machines." Applied Mechanics and Materials 844 (July 2016): 138–41. http://dx.doi.org/10.4028/www.scientific.net/amm.844.138.

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This paper describes general approach for creation the effective kinetic energy recovery system in mobile machines using flywheels. It’s should be a mechatronic system. The system with accelerometer-gyroscope and proportional, integral and differential controller (PID-regulator) is proposed as example of automatic control.

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17

Renedo Anglada, Jaime, Suleiman Sharkh, and Arfakhshand Qazalbash. "Influence of curvature on air-gap magnetic field distribution and rotor losses in PM electric machines." COMPEL - The international journal for computation and mathematics in electrical and electronic engineering 36, no. 4 (July 3, 2017): 871–91. http://dx.doi.org/10.1108/compel-05-2016-0200.

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Purpose The purpose of this paper is to study the effect of curvature on the magnetic field distribution and no-load rotor eddy current losses in electric machines, particularly in high-speed permanent magnet (PM) machines. Design/methodology/approach The magnetic field distribution is obtained using conformal mapping, and the eddy current losses are obtained using a cylindrical multilayer model. The analytical results are validated using a two-dimensional finite element analysis. The analytical method is based on a proportional-logarithmic conformal transformation that maps the cylindrical geometry of a rotating electric machine into a rectangular configuration without modifying the length scale. In addition, the appropriate transformation of PM cylindrical domains into the rectangular domain is deduced. Based on this conformal transformation, a coefficient to quantify the effect of curvature is proposed. Findings Neglecting the effect of curvature can produce significant errors in the calculation of no-load rotor losses when the ratio between the air-gap length and the rotor diameter is large. Originality/value The appropriate transformation of PM cylindrical domains into the rectangular domain is deduced. The proportional-logarithmic transformation proposed provides an insight into the effect of curvature on the magnetic field distribution in the air-gap and no-load rotor losses. Furthermore, the proposed curvature coefficient gives a notion of the effect of curvature for any particular geometry without the necessity of any complicated calculation. The case study shows that neglecting the effect of curvature underestimates the rotor eddy-current losses significantly in machines with large gap-to-rotor diameter ratios.

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18

Wei, Zhou Ling, and Bo Fu. "Design and Analysis of Nut Crimping Machines." Applied Mechanics and Materials 233 (November 2012): 88–91. http://dx.doi.org/10.4028/www.scientific.net/amm.233.88.

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In view of the growing market demand for self-locking nuts and the relative backward processing technology, a nut crimping machine was studied. According to the working principle of nut crimping and performance requirements, the body structure of the nut crimping machine was designed. The stress analysis of the main stressed components was performed using simulation Xpress function of SolidWorks. Results show that body structure has high strength and rigidity. Based on electro-hydraulic proportional technology, the hydraulic control circuit was developed. The design results improve the control precision on speed and pressure of the nut crimping machine and ensure the quality of self-lucking nuts.

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19

Tarasik, V. P., and V. S. Savitskiy. "Experimental research of electro-hydraulic proportional valve of mechatronic control system of automatic gearbox." Traktory i sel hozmashiny 83, no. 9 (September 15, 2016): 10–18. http://dx.doi.org/10.17816/0321-4443-66189.

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To control the mechanisms of automobiles, tractors, building and road machines, the mechatronic automatic control systems are commonly used; one of their most important components is the electro-hydraulic proportional valve. Mechatronic systems allow to implement the sophisticated adaptive control algorithms, provide the high quality of functioning processes of controlled mechanisms and significantly increase the efficiency of production processes. The article deals with the experimental research of characteristics of electro-hydraulic proportional valve and the optimization of parameters of its control implemented by the microprocessor controller. Such valves are applied in automatic transmissions for the control of gear shift and working organs. The key diagram of created valve is given; its interaction with mechanisms of mechatronic systems is shown. The system functioning in implementation process of its work algorithm under control of the microprocessor controller is described. The article describes the results of experimental research of the electro-hydraulic proportional valve and technical solutions that allow to improve significantly its performance. The static and transient responses of the valve and its components are obtained. It is found that the form of transient response of proportional solenoid depends on the power source characteristic. With the use of direct current source, the transient response corresponds to aperiodic link, but with the use of controller, it corresponds to oscillatory one. The oscillatory character of transient response is caused by the control action of current controller. Current controller parameters influence the relative overshoot and the delay time of current rise in the proportional solenoid winding. The optimal parameters of current controller settings are defined. Influence of oscillation of control signal on the hysteresis of static response of control mechanism is investigated. Parameters of electro-hydraulic proportional valve that allow to estimate the possibility of its application for the control of working organs of machines are described.

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20

KUMAR, DHANANJAY, and BENGT KLEFSJÖ. "PROPORTIONAL HAZARDS MODEL — AN APPLICATION TO POWER SUPPLY CABLES OF ELECTRIC MINE LOADERS." International Journal of Reliability, Quality and Safety Engineering 01, no. 03 (September 1994): 337–52. http://dx.doi.org/10.1142/s0218539394000246.

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The electric power supply cable is one of the most critical components of an electric mine loader. The effects of operating conditions such as fault types, cable types, numbers and types of repair done, the machines on which these cables are used, are analyzed using the proportional hazards model. The relatively important operating conditions influencing the life length of the cable are identified and their magnitudes are estimated. Before fitting any model to the data, simple graphical tools have been used in formulating covariates and selecting the suitable model. The proportional hazards model is found to be an effective tool for analyzing the effects of covariates. Graphical methods have been used to test the goodness-of-fit of the proportional hazards model.

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21

Stein, G. J. "New results on an electropneumatic active seat suspension system." Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering 214, no. 5 (May 1, 2000): 533–44. http://dx.doi.org/10.1243/0954407001527826.

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A vibration control system with an air spring as the actuator and proportional electropneumatic control has been developed at the Institute of Materials and Machine Mechanics, Bratislava. As the electropneumatic transducer, a proportional pressure control valve is used in contrast to the previously used proportional flow control valve. The vibration control is facilitated by a combination of a ‘sky hook’ feedback loop and a feedforward loop working on the so-called ‘sky cloud’ principle, compensating base vertical vibration. Good agreement between simulation results and measurement on a laboratory dummy system was observed. The dummy system was also subjected to narrow-band random excitation, prescribed for standardized laboratory tests of driver's seats. The improvement in driver's seat vibration control properties owing to the feedforward vibration compensation is 2.5-fold, i.e. by 8 dB in comparison with ‘sky hook’ feedback damping only. The system could be used for vibration control in automotive applications, especially for vehicles with an unsprung chassis (earth-moving machines, wheeled tractors) and in the heavy vehicles sector.

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22

Pontil, Massimiliano, and Alessandro Verri. "Properties of Support Vector Machines." Neural Computation 10, no. 4 (May 1, 1998): 955–74. http://dx.doi.org/10.1162/089976698300017575.

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Support vector machines (SVMs) perform pattern recognition between two point classes by finding a decision surface determined by certain points of the training set, termed support vectors (SV). This surface, which in some feature space of possibly infinite dimension can be regarded as a hyperplane, is obtained from the solution of a problem of quadratic programming that depends on a regularization parameter. In this article, we study some mathematical properties of support vectors and show that the decision surface can be written as the sum of two orthogonal terms, the first depending on only the margin vectors (which are SVs lying on the margin), the second proportional to the regularization parameter. For almost all values of the parameter, this enables us to predict how the decision surface varies for small parameter changes. In the special but important case of feature space of finite dimension m, we also show that there are at most m + 1 margin vectors and observe that m + 1 SVs are usually sufficient to determine the decision surface fully. For relatively small m, this latter result leads to a consistent reduction of the SV number.

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23

Riski, Sestri Novia. "SISTEM PAKAR UNTUK MENDETEKSI KESALAHAN ELEKTRODA PADA PROSES WELDING FRAME THERMOSTAT PADA SOULPLATE MENGGUNAKAN METODE FORWARD CHAINING BERBASIS WEB (STUDI KASUS PT PHILIPS)." Edik Informatika 3, no. 2 (October 9, 2017): 211–25. http://dx.doi.org/10.22202/ei.2017.v3i2.2248.

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The use of SMAW (Shielded Metal Arc Welding) in the industrial world is enough widely used. With this machine the human greatly helped by the need to make a metal object. So that by the frequent use of these tools, the more susceptible it is also a tool damage. Technicians machines supplied by the company are not proportional to the number of machines. Therefore, to help resolve this issue needs an expert system that can act as an assistant to the engineer. Data relating to the damage processed using forward chaining expert system. Expert systems are made using the programming language PHP and MySQL database so as to produce an expert system to detect damage SMAW web based. So it can help technicians solve problems SMAW and can also be used for the source of knowledge about the condition and its causes and solutions to overcome them.

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24

Khedlekar, U. K., A. Namdeo, and A. Nigwal. "Production inventory model with disruption considering shortage and time proportional demand." Yugoslav Journal of Operations Research 28, no. 1 (2018): 123–39. http://dx.doi.org/10.2298/yjor161118008k.

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The disruption in a production system occurs due to labor problem, machines breakdown, strikes, political issue, and weather disturbance, etc. This leads to delay in the supply of the products, resulting customer to approach other dealers for the products. This paper is an attempt to develop an economic production quantity model using optimization method for deteriorating items with production disruption. We obtained optimal production time before and after the system gets disrupted. We have also devised the model for optimizing the shortage of the products. This research is useful to determine the time for start and stop of the production when system gets disrupted. The optimal production and inventory plan are provided, so that the manufacturer can reduce the loss occurred due to disruption. Finally a graph based simulation study has been given to illustrate the proposed model.

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25

Dostál, Petr, Michal Černý, Jaroslav Lev, and David Varner. "Proportional monitoring of the acoustic emission in crypto-conditions." Acta Universitatis Agriculturae et Silviculturae Mendelianae Brunensis 59, no. 5 (2011): 31–38. http://dx.doi.org/10.11118/actaun201159050031.

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The work is aimed at studying corrosion and fatigue properties of aluminum alloys by means of acoustic emission (AE). During material degradation are acoustic events scanned and evaluated. The main objective of the article is a description of behavior of aluminum alloys degraded in specific conditions and critical degradation stages determination. The first part of the article describes controlled degradation of the material in the crypto–conditions. The acoustic emission method is used for process analyzing. This part contains the AE signals assessment and comparing aluminium alloy to steel. Then the specimens are loaded on high-cyclic loading apparatus for fatigue life monitoring. Also, the synergy of fatigue and corrosion processes is taken into account.The aim is the description of fatigue properties for aluminum alloys that have already been corrosion-degraded. Attention is also focused on the structure of fatigue cracks. The main part of the article is aimed at corrosion degradation of aluminium alloys researched in real time by means of AE. The most important benefit of AE detection/recording is that it provides information about the process in real time. Using this measurement system is possible to observe the current status of the machines/devices and to prevent serious accidents.

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26

Zhu, De Quan, Tao Mei, and Cheng Mao Cao. "Fuzzy Support Vector Machines Control for Robotic Manipulator." Advanced Materials Research 204-210 (February 2011): 301–5. http://dx.doi.org/10.4028/www.scientific.net/amr.204-210.301.

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To improve the control precision of robotic manipulator, fuzzy support vector machines control method for robotic manipulator was presented based on genetic algorithm and least square algorithm. Fuzzy algorithm was used to decouple joints. Using support vector machines, fuzzy logical control of complete process and treatment of non-linear signal were realized. The parameters of controller were optimized by hybrid learning algorithm. First, least square algorithm was used for off-line optimization to form support vector machines control system. Then, genetic algorithm was used for on-line optimization to get the optimal performance parameters of support vector machines and the optimal fuzzy proportional parameters. Simulation results of a two-link manipulator demonstrated that the control method designed gets tracking effect with high precision.

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27

Baram, Yoram. "Random Embedding Machines for Pattern Recognition." Neural Computation 13, no. 11 (November 1, 2001): 2533–48. http://dx.doi.org/10.1162/089976601753196012.

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Real classification problems involve structured data that can be essentially grouped into a relatively small number of clusters. It is shown that, under a local clustering condition, a set of points of a given class, embedded in binary space by a set of randomly parameterized surfaces, is linearly separable from other classes, with arbitrarily high probability. We call such a data set a local relative cluster. The size of the embedding set is shown to be inversely proportional to the squared local clustering degree. A simple parameterization by embedding hyperplanes, implementing a voting system, results in a random reduction of the nearest-neighbor method and leads to the separation of multicluster data by a network with two internal layers. This represents a considerable reduction of the learning problem with respect to known techniques, resolving a long-standing question on the complexity of random embedding. Numerical tests show that the proposed method performs as well as state-of the-art methods and in a small fraction of the time.

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28

Huang, Peichen, Zhigang Zhang, and Xiwen Luo. "Feedforward-plus-proportional–integral–derivative controller for agricultural robot turning in headland." International Journal of Advanced Robotic Systems 17, no. 1 (January 1, 2020): 172988141989767. http://dx.doi.org/10.1177/1729881419897678.

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Traveling along straight lines and headland turning are two common motions during the automatic guidance of agricultural machines. However, most studies focus on accurately following parallel tracks in the field and seldom consider the maneuvers at the end of each row. Moreover, numerous studies have mainly focused on planning the global trajectories in the entire field to increase field efficiency, and very few works are related to maneuver generation and vehicle control in headlands. In this study, a feedforward-plus-proportional–integral–derivative controller for a differential drive robot in headland turning was developed. The feedforward-plus-proportional–integral–derivative controller consisted of a feedforward and a feedback loop. The feedforward loop was designed based on the heading errors of a lookahead point on the planning path. The feedback loop was designed based on radial errors to improve the tracking accuracy. Field comparison tests of feedforward, feedback, and feedforward-plus-proportional–integral–derivative controllers were conducted. Experimental results showed that the feedforward-plus-proportional–integral–derivative had better tracking results and took less turning time.

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29

Liu, Chengcheng, Jiawei Lu, Youhua Wang, Gang Lei, Jianguo Zhu, and Youguang Guo. "Design Issues for Claw Pole Machines with Soft Magnetic Composite Cores." Energies 11, no. 8 (August 1, 2018): 1998. http://dx.doi.org/10.3390/en11081998.

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By using global ring winding, the torque coefficient of the transverse flux machine (TFM) is proportional to its number of pole pairs, and thus the TFM possesses high torque density ability when compared with other electrical machines. As a special kind of TFM, the claw pole machine (CPM) can have more torque due to its special claw pole teeth. The manufacturing of CPM or TFM with silicon steels was very difficult in the past, and is a handicap for the progress of this kind of machine. Thanks to the advent of soft magnetic composite (SMC) materials, the manufacturing process of CPM has become more and more simple. More attention has been paid to this kind of technology, and some mass production CPMs with SMC cores have appeared. However, there are few works that discuss the key design issues for this kind of machine. In this paper, a small CPM with SMC is used as as a research benchmark. Various design methods that can be adopted to improve its performance have been studied, including unequal stator claw pole teeth, a skewing magnet design, consequent pole design, and etc. The 3D finite element method (FEM) is used for the machine analysis, and it is verified by the experimental results of a CPM with SMC cores.

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30

Yu, Hsing-Cheng, Hung-Wei Lai, Li-Jhen Chen, and Cheng-Kai Lin. "Low cogging torque design and simplified model-free predictive current control for radial-flux dual three-phase permanent magnet electric machines." Advances in Mechanical Engineering 11, no. 12 (December 2019): 168781401989164. http://dx.doi.org/10.1177/1687814019891644.

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This study presents two improved designs of eccentric-shaped permanent magnets and teeth-shaped stators in radial-flux dual three-phase permanent magnet electric machines to reduce cogging torque and torque ripple. The finite element analysis (ANSYS Electromagnetics) has been adopted in simulation, and real radial-flux dual three-phase permanent magnet electric machines have been fabricated in experiment to verify the study. Using the radial-flux dual three-phase permanent magnet electric machines in electric machine systems can improve the reliability and obtain higher output torque. In electrical drives and control, a simplified model-free predictive current control method has been proposed and implemented to drive the radial-flux dual three-phase permanent magnet electric machines, and the control law has been achieved by a TMS320F28377S microcontroller of Texas Instruments. The simplified model-free predictive current control method is senseless to parameter variations and back electromotive force of the permanent magnet electric machines, and only needs current sensors to detect six-phase current. The optimal one has been chosen by 14 various switching modes, which has the minimum cost function, and then the converter can be directly driven and controlled in the next sampling period. The features of the simplified model-free predictive current control method can reduce the algorithm calculation and avoid the defect of conventional model-based predictive current control scheme. A proportional-integral speed controller has also been designed to achieve the speed response of the fixed-speed tracking effect. Finally, the feasibility and effectiveness of the proposed simplified model-free predictive current control method for the dual three-phase permanent magnet electric machines can be verified in the experimental and quantitative results.

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31

Usman, Hina, Junaid Ikram, Khurram Saleem Alimgeer, Muhammad Yousuf, Syed Sabir Hussain Bukhari, and Jong-Suk Ro. "Analysis and Optimization of Axial Flux Permanent Magnet Machine for Cogging Torque Reduction." Mathematics 9, no. 15 (July 23, 2021): 1738. http://dx.doi.org/10.3390/math9151738.

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In this paper, a hexagonal magnet shape is proposed to have an arc profile capable of reducing torque ripples resulting from cogging torque in a single-sided axial flux permanent magnet (AFPM) machine. The arc-shaped permanent magnet increases the air-gap length effectively and makes the flux of the air-gap more sinusoidal, which decreases air-gap flux density and hence causes a reduction in cogging torque. Cogging torque is the basic source of vibration, along with the noise in PM machines, since it is the main cause of torque ripples. Cogging torque is independent of the load current and is proportional to the air-gap flux and the reluctance variation. Three-dimensional finite element analysis (FEA) is used in the JMAG-Designer to analyze the performance of the conventional and proposed hexagonal-shaped PM AFPM machines. The proposed shape is designed to reduce cogging torque, and the voltage remains the same as compared to the conventional hexagonal-shaped PM machine. Further, optimization is performed by utilizing an asymmetric overhang. Latin hypercube sampling (LHS) is used to create samples, the kriging method is applied to approximate the model, and a genetic algorithm is applied to obtain the optimum parameters of the machine.

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32

Lanets, Oleksii, Volodymyr Borovets, Pavlo Maistruk, and Iryna Derevenko. "SUBSTANTIATION OF RATIONAL SELECTION OF MOTOR-VIBRATORS VIBRATION MACHINES." Vibrations in engineering and technology, no. 3(94) (November 26, 2019): 24–32. http://dx.doi.org/10.37128/2306-8744-2019-3-4.

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An integral component in the calculation of vibration machines is the establishment of drive power necessary to set in motion an oscillating system with specified characteristics. However, difficulties often arise at this stage. The inertial characteristics of the drive directly affect the power consumption. Therefore, when calculating it, you must already know the size of the drive, which is still unknown, since it is only being installed. This question is especially relevant for low-frequency oscillatory systems with an inertial drive, in which the inertial parameters of the drive are proportional to the masses of the oscillatory systems. In such oscillatory systems, ignoring the mass of the drive when setting the consumed power to set the mechanical oscillating system in motion can lead to the fact that the vibrating machine will not be able to provide the expected (calculated) technical and technological parameters, since the massive drive oscillates with the whole system, will take on its own propulsion a significant proportion of the energy. The article justifies the analytical relation¬ships for calculating the power of vibration machines with inertial drive, taking into account the mass of vibrator motors. For this, systems of equations are solved that interconnect analytical expressions for calculating the powers necessary to bring the oscillatory systems into motion, taking into account the mass of vibrator motors. The solution to such systems is the value of the required drive power (vibrator motors) and its mass, which is already consistent with the masses of unified vibrator motors produced by manufacturers. The obtained analytical dependences make it quite easy to determine the power of the drives in one-, two- and trimass oscillation systems of vibration machines with an inertial drive. Using the formulas obtained in the article, it is possible to precisely establish the necessary drive power to set the oscillatory system in motion and uniquely select the mass of the vibrator motor.

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Lu, Junjie, Jinquan Huang, and Feng Lu. "Distributed Kernel Extreme Learning Machines for Aircraft Engine Failure Diagnostics." Applied Sciences 9, no. 8 (April 25, 2019): 1707. http://dx.doi.org/10.3390/app9081707.

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Kernel extreme learning machine (KELM) has been widely studied in the field of aircraft engine fault diagnostics due to its easy implementation. However, because its computational complexity is proportional to the training sample size, its application in time-sensitive scenarios is limited. Therefore, in the case of largescale samples, the original KELM is difficult to meet the real-time requirements of aircraft engine onboard condition. To address this shortcoming, a novel distributed kernel extreme learning machines (DKELMs) algorithm is proposed in this paper. The distributed subnetwork is adopted to reduce the computational complexity, and then the likelihood probability and Dempster-Shafer (DS) evidence theory is used to design the fusion scheme to ensure the accuracy after fusion is not reduced. Afterwards, the verification on the benchmark datasets shows that the algorithm can greatly reduce the computational complexity and improve the real-time performance of the original KELM algorithm without sacrificing the accuracy of the model. Finally, the performance estimation and fault pattern recognition experiments of an aircraft engine show that, compared with the original KELM algorithm and support vector machine (SVM) algorithm, the proposed algorithm has the best performance considering both real-time capability and model accuracy.

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34

Park, Seok Hong, Duc Viet Dang, and Trung Thanh Nguyen. "Development of a Servo-Based Broaching Machine Using Virtual Prototyping Technology." Strojniški vestnik - Journal of Mechanical Engineering 63, no. 7-8 (July 17, 2017): 466. http://dx.doi.org/10.5545/sv-jme.2017.4384.

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Predicting machine tool performance at the design stage is one way to resolve the time issue and achieve cost savings. The objective of this paper was to develop a new non-hydraulic broaching machine using a servo motor, ball screw, and roll element linear guide using virtual prototyping technology. First, we developed a multi-body simulation model (MBS) of a servo-based broaching machine to investigate its dynamic behaviour. Then, an adaptive sliding mode proportional-integral-derivative (PID)-based controller (ASMPID) was proposed to conduct the broaching process. We then performed a co-simulation between the mechanical structure and virtual controller to investigate the ram body trajectory and identify the optimal control parameters. Finally, we manufactured a prototype machine to evaluate the simulation results and determine the benefits of the new system. Our results indicated that the proposed model, which includes a mechanical structure and intelligent controller, effectively improved broaching machine design. Therefore, this work is expected to improve the prototyping efficiency of new broaching machines.

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35

Findura, P., J. Turan, J. Jobbágy, M. Angelovič, and O. Ponjican. "Evaluation of work quality of the green peas harvester Ploeger EPD 490." Research in Agricultural Engineering 59, No. 2 (May 31, 2013): 56–60. http://dx.doi.org/10.17221/5/2012-rae.

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Machines for harvesting vegetable must reliably collect the given type of vegetables at various climatic conditions, and with adequate performance, quality and low losses. Machines for harvesting of green peas must be sufficiently reliable and handling must be simple. The criteria of their work are based on harvested product quality, and the size of losses incurred depends on the rate of release of pods from the plants and on the release of grains from pods. The size of loss of grain and pods in the field and grain damages in the storage tank is directly proportional to the appropriately selected operating mode of the machine. Resistance to the damage of grain can be partly affected by selecting varieties with appropriate physical and mechanical properties and by choosing appropriate operating speed of the collector of green peas. Experimental measurements were carried out in the cooperative farm Zemné, Slovak Republic, within a conventional tillage technology, which has suitable conditions for the cultivation of this commodity. The subject of research was green peas Ploeger EPD 490.  

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36

Munawaroh, Catur, Suminah Suminah, and Hanifah Ihsaniyati. "PENGARUH PENGALAMAN PETANI DAN PENGARUH ORANG LAIN TERHADAP ADOPSI MESIN TANAM RICE TRANSPLANTER DI KECAMATAN MOJOLABAN KABUPATEN SUKOHARJO." AGRITEXTS: Journal of Agricultural Extension 43, no. 1 (May 14, 2020): 16. http://dx.doi.org/10.20961/agritexts.v43i1.41626.

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<p>This research aimed to observe the farmer’s experience, other people’s influence, farmer’s attitude to the adoption of rice transplanter planting machine and farmer’s adoption to the rice transplanter planting machine is Mojolaban Sub-district of Sukoharjo District and to observe the effect of farmer’s experience, other people’s influence and attitude in partially and simultaneously to the adoption of rice transplanter planting machine in Mojolaban Sub-district of Sukoharjo District. The basic method used was qualitative. The research location was determined as purposive in Mojolaban District. The sampling was done using proportional random sampling research method with the number of 60 respondents. The data collection technique was using observation, interview, and documentation. The data analysis method was using path analysis method.The research result showed that farmer’s experience in Mojolaban Sub-district was low, other people’s influence was rare, farmer’s attitude to the adoption of rice transplanter planting machine was disagree and farmer’s adoption to the rice transplanter planting machine was never adopt. Partially, farmer’s experience significantly effected to the adoption of rice transplanter planting machine directly greater than the attitude, the influence of other people has no significant effect on the adoption of rice transplanter planting machines and the attitude of farmers has a significant effect on the adoption of rice transplanter planting machines in Mojolaban District, Sukoharjo Regency. Farmer’s experience, other people’s influence and attitude simultaneously significantly affected to the adoption of rice transplanter planting machine in Mojolaban Sub-district of Sukoharjo District.</p>

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37

Chouidira, Ibrahim, Djalal Eddine Khodja, and Hani Benguesmia. "Detection and Diagnosis faults in Machine asynchronous based on single processing." International Journal of Energetica 4, no. 1 (June 30, 2019): 11. http://dx.doi.org/10.47238/ijeca.v4i1.89.

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In this work, we proposed multi-winding model for the simulation of broken bars in squirrel cage asynchronous machine, this model allows to study the influence of the broken bar defects on the behavior general of machines in different operating conditions (healthy and faulty). The breaking of the most frequent bars of the rotor causes oscillations of the torque, speed, and the current, the increase of the resistance of the rotor creates the defects proportional with the number of breaks bar K .The diagnosis fault using technique of single processing based on Spectrum analysis for detection broken bar. The results of the simulation obtained allowed us to show the importance of this technique for detection broken bar.

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38

Kaczmarczyk, Waldemar. "Modelling Set-up Times Overlapping Two Periods in the Proportional Lot-Sizing Problem with Identical Parallel Machines." Decision Making in Manufacturing and Services 7, no. 1-2 (2013): 43. http://dx.doi.org/10.7494/dmms.2013.7.1.43.

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39

Laksono, Pranoto Budi. "ANALYSIS OF THE INFLUENCE OF LOOSE TERMINATION LEVEL WITH INCREASING TERMINATION TEMPERATURE OF ELECTRICAL EQUIPMENT USING INFRARED THERMOGRAPHY." TEKNOKOM 5, no. 1 (March 2, 2022): 78–87. http://dx.doi.org/10.31943/teknokom.v5i1.68.

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The use of electrical energy in the industrial is very important to drive production machines. Machine maintenance is carried out so that the lifetime of the machine becomes longer so that the production process continues. Temperature is one of the most common indicators of the structural health of equipment and components. This means that the main symptoms of damage to machines and equipment can be indicated by increasing the temperature of the equipment. One of the symptoms of an increase in equipment temperature is due to a loose cable termination. The use of infrared thermography to measure the temperature rise due to loose termination is one of the methods in electrical machine maintenance. Previous studies using infrared thermography to measure the temperature rise due to loose termination have been carried out by many researchers, but these studies did not show a correlation between the level of loose termination and the increase in temperature but only stated that the loose termination caused an increase in temperature. This study focuses on finding the relationship between the level of loose termination compared to standard torque and the increase in temperature at the termination point. This is very useful as a quick overview in determining the level of urgency in maintenance activity, that percentage of loose termination of a certain value below the standard will give an increase in temperature of a certain value as well. This study resulted, for the torque setting condition 67% below the standard (loose) the temperature increase at the terminal was 13.4% - 15.6%, for the torque setting condition 33% below the standard temperature increase at the terminal of 12.3% -13.8% which mean that the increase in temperature is directly proportional to the level of slack termination and is also directly proportional to the increase in the motor speed. If the termination torque level is lower and the motor speed is increased, the terminal temperature rise will be drastically rise.

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40

Mikolajczyk, Tadeusz, Tomasz Paczkowski, Danil Yurievich Pimenov, Mozammel Mia, Karali Patra, Grzegorz Krolczyk, Munish Kumar Gupta, and Jaroslaw Zdrojewski. "Analysis of the Deviation in a Low-Cost System for Stepless Digital Control of Conventional Lathe Spindle Speeds." Applied Sciences 9, no. 1 (December 20, 2018): 12. http://dx.doi.org/10.3390/app9010012.

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A conventional manual lathe electric motor drives the multi-stage gearbox transmitting torque to the spindle so that the workpiece makes contact with the machine tool at a given speed. The cutting speed is proportional to both the diameter of the workpiece and the spindle speed, however, the increments in spindle speed are limited. Manual lathe machines cannot be regulated at the optimum cutting speeds for all diameters. An innovative modernization of the main driveline of a TSB16 manual lathe is proposed in this paper, allowing for a cost-effective system for digital control of spindle speeds using an inverter. The inverter is controlled using an 8-bit AO (analog output) converter with special software developed with Visual Basic. The results of the analysis and various test runs with this new system for automated control of spindle rotation, showed that the required cutting speed can be achieved for any workpiece diameter. The deviation of cutting-speed of the upgraded system for any turning diameter is greatly reduced in comparison with the deviation of cutting-speed of a manual lathe. Finally, tests on this versatile system demonstrated a cost-effective method for modernizing the drive system of conventional lathe machines.

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41

Yepes, Alejandro G., Ana Vidal, Jano Malvar, Oscar Lopez, and Jesus Doval-Gandoy. "Tuning Method Aimed at Optimized Settling Time and Overshoot for Synchronous Proportional-Integral Current Control in Electric Machines." IEEE Transactions on Power Electronics 29, no. 6 (June 2014): 3041–54. http://dx.doi.org/10.1109/tpel.2013.2276059.

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42

Wang, Fengxiang, Junxiao Wang, Ralph M. Kennel, and Jose Rodriguez. "Fast Speed Control of AC Machines Without the Proportional-Integral Controller: Using an Extended High-Gain State Observer." IEEE Transactions on Power Electronics 34, no. 9 (September 2019): 9006–15. http://dx.doi.org/10.1109/tpel.2018.2889862.

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43

Alkorta, Patxi, Oscar Barambones, José Cortajarena, Itziar Martija, and Fco Maseda. "Effective Position Control for a Three-Phase Motor." Electronics 9, no. 2 (February 1, 2020): 241. http://dx.doi.org/10.3390/electronics9020241.

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This document presents an efficient proportional derivative (PD) position controller for three-phase motor drives. The regulator has been designed in frequency domain, employing the direct–quadrature (d–q) synchronous rotating reference frame and the indirect vector control. The presented position regulator is easy to tune and incorporates a feed forward (FF) term to compensate effectively the effect of the load disturbance. This position controller has been validated experimentally by using two industrial three-phase motors: an induction motor (IM) of 7.5 kW and a permanent magnet synchronous motor (PMSM) of 3.83 kW. The inner proportional integral (PI) current loops of both machines have also been designed in the frequency domain. Each machine has connected in its shaft an incremental encoder of 4096 pulses per revolution, to measure the position. Several simulations and experimental tests have been carried out with both motors, in favorable conditions and also with various types of adversities (parametric uncertainties, unknown load disturbance and measurement noise in the position and current loops), getting very good results and suggesting that this controller could be used in the research area and also in the industry.

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44

Enamhe, Dornklaimz, Chidiebere U. Enukoha, Pius U. Angioha, and Manderson Kusi. "Motivation Behind E-Trust of Electronic banking Channels by Banks." ARRUS Journal of Engineering and Technology 1, no. 2 (February 12, 2022): 67–80. http://dx.doi.org/10.35877/jetech679.

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This quantitative study attempts to validate the adoption of electronic banking channels by commercial banks for operational performance. The study was a survey that adopted a structured self-designed questionnaire to elicit data from management staff selected from commercial banks in Cross River states using proportional and simple random sampling techniques. Descriptive statistics and Pearson Product Moment correlation was used to analyse the collected data. Electronic banking channels were measured by automated teller machines and internet banking to analyse the data, and this was measured continuously. Analyse results validates the adoption of electronic banking channels (Automated teller machines and Internet banking). The study suggests factors that improve digital banking for bank profitability and operational performance based on these findings

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45

Li, Shenghu. "Configuration of Jacobian Matrix in Steady-State Voltage Stability Analysis Based on Rotor Flux Dynamics of Rotating Machines." International Journal of Emerging Electric Power Systems 14, no. 3 (June 19, 2013): 239–44. http://dx.doi.org/10.1515/ijeeps-2012-0013.

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Abstract In the existing literatures, modal analysis for steady-state voltage stability is based on the reduced Jacobian matrix, i.e. active power equations are eliminated, and reactive power equations of the constant power/voltage buses (PV buses) are ignored in the polar coordinate expression, which is actually designed for voltage controllability, but questionable for voltage stability.In this article, power outputs of the rotating machines are newly decomposed to the steady-state and dynamic components, with the latter proportional to derivative of the rotor flux. Therefore, neither the active nor the reactive power equations of the rotating machines may be eliminated or ignored in the Jacobian matrix. Only the static buses with constant load impedance should be eliminated. Numerical results show that elimination of active power equations or ignorance of reactive power equations of the rotating machines will yield optimistic stability margins, while including power equations of static load buses yields pessimistic stability margin. It is also find that more static load component yields larger stability margin.

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46

Fetene, Yeshiwas, and Dereje Shibeshi. "Fractional Order Sliding Mode Speed Control of Feedback Linearized Induction Motor." Power Electronics and Drives 5, no. 1 (January 1, 2020): 109–22. http://dx.doi.org/10.2478/pead-2020-0010.

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Abstract Induction machines have of late become the most popular workhorses in the industry replacing DC machines because of their advantages, such as reduced cost, reliability and the absence of commutators, which make them adapt to unfavourable conditions with lower maintenance requirement. However, higher-order models of AC machines, nonlinearities in model equations, uncertainties in parameters and load disturbances make induction motors difficult to control than that of DC motors. In this paper, a robust control strategy considering the recent advances in technology is proposed employing input-output feedback linearization for the exact decoupling of electromagnetic torque and rotor flux using fractional-order sliding mode controller (SMC) for the outer speed loop. The sliding mode observer is also designed to extract the rotor flux from the DC input voltage of the inverter and stator current measurements. Finally, a comparison between the commonly used proportional integral and derivative (PID) controller and the proposed fractional-order SMCs is made and the conclusion is reached.

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47

Plotnikov, S. M. "Determination of eddy current losses and hysteresis losses in magnetic circuits of electrical machines." Izmeritel`naya Tekhnika, no. 11 (2020): 54–58. http://dx.doi.org/10.32446/0368-1025it.2020-11-54-58.

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The division of the total core losses in the electrical steel of the magnetic circuit into two components – losses dueto hysteresis and eddy currents – is a serious technical problem, the solution of which will effectively design and construct electrical machines with magnetic circuits having low magnetic losses. In this regard, an important parameter is the exponent α, with which the frequency of magnetization reversal is included in the total losses in steel. Theoretically, this indicator can take values from 1 to 2. Most authors take α equal to 1.3, which corresponds to the special case when the eddy current losses are three times higher than the hysteresis losses. In fact, for modern electrical steels, the opposite is true. To refine the index α, an attempt was made to separate the total core losses on the basis that the hysteresis component is proportional to the first degree of the magnetization reversal frequency, and the eddy current component is proportional to the second degree. In the article, the calculation formulas of these components are obtained, containing the values of the total losses measured in idling experiments at two different frequencies, and the ratio of these frequencies. It is shown that the rational frequency ratio is within 1.2. Presented the graphs and expressions to determine the exponent α depending on the measured no-load losses and the frequency of magnetization reversal.

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48

Żokowski, Mariusz, Krzysztof Falkowski, Paulina Kurnyta-Mazurek, and Maciej Henzel. "Control of bearingless electric machines dedicated for aviation." Aircraft Engineering and Aerospace Technology 92, no. 1 (January 6, 2020): 27–36. http://dx.doi.org/10.1108/aeat-11-2018-0293.

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Purpose The paper presents the results of work on control systems of bearingless electric motors. Authors proposed the applications of bearingless electric machines for aircraft actuation system. Suggested solution characterizes novel concept of on-board equipment design such as More Electric Aircraft. Magnetic suspension technology allows elimination of friction force and the negative performance features of classic bearing system. However, to achieve all these purposes appropriately, dedicated control system must be also applied. Design/methodology/approach The development of a control system of bearingless electric machine is presented in detail. Mathematical model and construction of induction bearingless motor are widely discussed. Then, proportional–integral-derivative controller algorithm designing for BEM control system was presented using the well pole placement method. Simulation model of BEM control system with use of Matlab-Simulink software was shown. Finally, experimental studies on laboratory stand were introduced. The paper presents design methodology of conventional and advanced control system of bearingless motor. Findings The presented concept of the bearingless electric machines could be applied in the on-board actuation system. During research, full control system of bearingless electric motor was designed and tested. This system consisted of two subsystems. The first responded for rotary speed stabilization and second one was designed for position control of the rotor in the air gap. Practical implications The presented concept of the bearingless electric machines could be applied in the on-board actuation system. During research, full control system of bearingless electric motor was designed and tested. This system consisted of two subsystems. The first responded for rotary speed stabilization and second one was designed for position control of the rotor in the air gap. Originality/value The idea of active magnetic suspension system will be implemented for aviation on technology readiness level V. The paper presents unique laboratory stand with bearingless electric motor and experimental studies. The stable time responses of designed control system were presented and discussed. In addition, preliminary considerations of advanced control system with robust controller were introduced as well.

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49

Wei, Xing, Yongji Wang, Shuai Dong, and Lei Liu. "A Three-Dimensional Cooperative Guidance Law of Multimissile System." International Journal of Aerospace Engineering 2015 (2015): 1–8. http://dx.doi.org/10.1155/2015/479427.

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In order to conduct saturation attacks on a static target, the cooperative guidance problem of multimissile system is researched. A three-dimensional guidance model is built using vector calculation and the classic proportional navigation guidance (PNG) law is extended to three dimensions. Based on this guidance law, a distributed cooperative guidance strategy is proposed and a consensus protocol is designed to coordinate the time-to-go commands of all missiles. Then an expert system, which contains two extreme learning machines (ELM), is developed to regulate the local proportional coefficient of each missile according to the command. All missiles can arrive at the target simultaneously under the assumption that the multimissile network is connected. A simulation scenario is given to demonstrate the validity of the proposed method.

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50

Xu, Li Ping, and Lan Jie Li. "Design of Hydraulic Loading System for the Little Loading Bearing Testing Machine." Applied Mechanics and Materials 741 (March 2015): 490–94. http://dx.doi.org/10.4028/www.scientific.net/amm.741.490.

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Utilizing hydraulic loading to achieve a little loading, is one of the hydraulic loading technical problems. For the purpose of bearing testing machines’ little loading, a hydraulic loading method was presented based on damps and electro-hydraulic proportional technique. Damps decreased the pressure and shunted. Damps calculation and the loading principle were researched, and the system was simulated with AMESim software. The result shows that this system meets the little loading requirement.

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