Number Of Control Elements Research Articles

Heating System Control with Neural Network

Building performance has significant impact on humans’ life and ecology as buildings account for 39% of total greenhouse gas emissions and consume about 40% of total global energy consumption. Smart building control is one of the key points to archive high energy efficiency. Each year, the complexity of building state control grows due to the increase in the number of controlled elements that are used to achieve better indoor climate. Therefore, in the manual analysis and implementation of the building control program, an error can easily appear due to the human factor. Artificial intelligence (AI) algorithms could be used as an alternative solution as they could evaluate building dynamics independently. One of strategies for automatic building control adaptation to its dynamic is model based predictive control where neural network is used for different control strategies evaluation. Performance of such control technique is highly dependent on control strategies evaluation accuracy. To achieve top accuracy, several hyperparameters of neural network could be tuned as well as data set for specific construction must be prepared. Preparation of data set could be a problem as random control of building for generation of dataset could be not unacceptable for building users as well as it could damage construction.In this paper authors process optimization of experimental building heating system control algorithm to achieve smaller fluctuations of temperature indoors. For dataset generation were used several data from weather station as well as heating system parameters and temperature indoors while building was controlled by thermostat with build in PID regulation. For evaluation of building dynamics were used temporal convolutional neural network. To achieve high accuracy results of control strategies evaluation, several hyperparameters of neural network were tested. Finally resulting model were tested on physical building. Results indicate that in some cases developed control model could prevent temperature fluctuations which could be caused by limits of heating system power.

Research on the Optimization and Evaluation of Excavator Human-Machine Interface Layout Based on Situation Awareness

In order to solve the problem of a large number of types and complex layouts of control devices on the operator interface of mining excavators, and a large variety and number of control elements on the control panel, the layout optimization design is carried out by applying the theoretical model of situational awareness and the influencing factors to the layout design of the human-machine interface. The modularity of the interface and the hierarchy of the original components are divided, and the importance evaluation indicators established according to situational awareness are weighted according to the entropy weighting method, and then the results are combined with the VIKOR method to analyse the importance of the interface components and the control panel module respectively before the interface is optimised and designed. The results show that the application of situational awareness theory to HMI design can play an important role in enhancing the level of situational awareness of operators and meeting their needs.

Analysis of basic concepts of advanced engines for supersonic civil aircraft on the basis of foreign designers’ experience

The work contains the results of a study of the basic design concepts of advanced engines for supersonic civil aircraft, carried out in order to make a forecast for the development of aviation technology, taking into account the experience of foreign designers. Engine designs are presented that are considered to be the most rational ones from the point of view of achieving high technical and economic parameters in the range of cruise Mach numbers from 1.2 to 5. Advantages and disadvantages of various engine designs, as well as issues of engine regulation at different flight modes, are discussed. The parameters of some engines being developed and studied at present for supersonic civil aircraft are presented. The analysis of the designs shows that an increase in the cruise Mach number leads to a complication of engine designs in the direction of an increase in the number of controlled elements, the number of working fluid flow paths, a complication of the architecture of turbomachines, as well as in the direction of using combined schemes and alternative fuels. The aspiration to meet new reinforced ecological requirements through the use of new, complex engine designs that differ significantly from traditional gas turbine engines will inevitably entail additional technical risks due to the insufficient level of technological readiness of most of the new controlled units.

A New Method of Regulating the Cooling Capacity of a Cooling System with CO2

New guidelines set by international organizations for refrigeration companies cause that natural working fluids such as carbon dioxide are increasingly used in new refrigeration systems. Carbon dioxide (R-744) is used in freezing, cooling, or air conditioning installations, in which the cooling load fluctuates hourly. To adapt the cooling capacity of the evaporator to the current cooling load of the cooled space, a number of control elements are used. The paper proposes a new method of regulating the cooling capacity for a one-stage refrigeration cycle with the R-744 refrigerant and an internal heat exchanger (IHX). The proposed method involves using an additional evaporator and combines the possibility of regulating the cooling capacity with the possibility of energy efficiency ratio (EER) improvement. The energy analysis of the proposed method of regulating the cooling capacity was performed and the results were compared with the control method. The control method was using the compressor hot gas bypass valve which allows the flow of hot vapor refrigerant to the suction side. The energy analysis was carried out for both subcritical and supercritical cycles using the energy equations. For each of the considered methods, the characteristics of the change in the EER as a function of the reduction of the cooling capacity in both supercritical and subcritical cycles were determined. It was found that when the cooling capacity decreased by 50%, the hot gas bypass regulating method was around 30% less efficient compared to the proposed additional evaporator regulating method.

Approaches to solving the problem of search of scenarios of lessons on informatics for basic school in the Moscow E-School library

Problem and goal. The article deals with the problem of search of scenarios of lessons on informatics for basic school in the Moscow E-School (MESH) Library. The goal is to identify the features of the MESH search engine and possible approaches to improving the process of scenarios of informatics lessons for basic school. Methodology. In the process of research was used a set of methods: analysis of the resources of the MESH library and normative documents; reflection of the content of knowledge obtained; searching for approaches to improving the process of finding scenarios of informatics lessons for basic schools in the MESH library; local pedagogical experiment. Results. Revealed the difference of the classification of sections and themes of the school informatics course provided by the Approximate Basic Educational Program [16] (in accordance with General Educational Standards [20]) and the MESH library classification [3], as well as the presence of a large number of controlled elements of MESH library content, indicated by the creators of the scenarios of lessons on informatics for basic school, what determines the problem of finding the right resources. The results of the study allowed to find approaches to solving the identified problem. Conclusion. The approaches to solving the identified problem of search of scenarios of lessons on informatics for basic school in the MESH library are proposed, their implementation can have a positive impact on the ability to find the necessary digital resource and, as a result, increase the effectiveness of professional activity of basic school informatics teacher.

Instructional laboratory for practical investigation of electric drive control

The study discusses the design principles of instructional laboratory equipment applied for practical investigations of electric drive control. The laboratory workstations comprise of two-motor hardware systems where each motor is controlled by a real-time DSP board. A control structure under test is assembled at the software level using a number of control elements, which is then compiled into a control algorithm for the microcontroller. In order to provide safe test execution, the control algorithm operates under the supervision of a real-time core software ensuring protection of the motors and the power converters. Due to the improvement in the reliability of hardware operation, the rated power of the motors and converters is increased to >1 kW to provide a proper characterisation of electric drives similar to industrial installations. The study also describes the laboratory hardware and software details using an example of the control system for an induction motor based on flux-vector control strategy. The example demonstrates configuring the control systems, compiling it into the execution code, the test procedure and result analysis.

Building implicit-surface-based composite porous architectures

We propose a simple but effective implicit-surface-based (ISB) method for constructing composite porous scaffolds (including gradient, hybrid, hierarchical, stochastic porous structures, or their combinations) based on a certain number of control elements (points, line segments, polylines, polygons, etc.) that are provided by users. Our method efficiently integrates spatial partitioning and substructure assignments in an easy manner. Users need not consider complex transitions between substructures during design, as these are naturally constructed. Also, our method can easily reconstruct native tissue structures based on micro-CT data. Here we successfully fabricated porous scaffolds with polymer as well as titanium using additive manufacturing (AM) techniques for ready use in tissue engineering.

Experimental Analysis of a Cantilever Beam with a Shunted Piezoelectric Periodic Array

The use of both shunted piezoelectric elements and periodic arrays have been investigated independently as well as used in conjunction to modify the vibration of a system. Piezoelectric patches bonded to a cantilever beam which is shunted with an active circuit, specifically a negative capacitance shunt, can control broadband flexural vibrations of a structure. Also, periodic arrays integrated into a structure allow for modification of propagating waves through the mechanical ‘‘stop-bands’’. The performance of a combined shunted periodic piezoelectric patch array will be analyzed in this study by investigating the velocity amplitude of the beam upstream and downstream of the array section and the number of control elements in the array. The negative capacitance shunts caused a global spatial average velocity reduction of 5 dB at the modal peaks from 500 to 5000 Hz. The reduction is shown to be greater in the downstream section of the beam. Also, by increasing the number of patches in the array, the attenuation of the resonances increased non-linearly. The results show that a negative capacitance periodic control array is an effective global vibration reduction system and has the ability to localize energy near the forcing of a structure.

Wavelength and Waveband Assignment for Ring Networks Based on Parallel Multi-granularity Hierarchical OADMs

In this paper we study the optimization issues of ring networks employing novel parallel multi-granularity hierarchical optical add-drop multiplexers (OADMs). In particular, we attempt to minimize the number of control elements for the off-line case. We present an integer linear programming formulation to obtain the lower bound in optimization, and propose an efficient heuristic algorithm called global bandwidth resource assignment that is suitable for the design of large-scale OADM networks.

Performance of Subaru Cassegrain Adaptive Optics System

Abstract The design and performance of the Cassegrain Adaptive Optics (AO) system for the 8.2 m Subaru Telescope are reported. The system is based on a curvature wavefront sensor with 36 photon-counting avalanche photodiode modules and a bimorph wavefront correcting deformable mirror with 36 driving electrodes. The engineering first light of the AO system took place in 2000 December. The AO system has been in service since 2002 April for two open-use instruments, an infrared camera and spectrograph and a coronagraph imager with adaptive optics. The Strehl ratio in the $K$-band is around 0.3 for bright guide stars under ${0\rlap {.}{}^{\mathrm {\prime \prime }}4} K$-band seeing condition. The control loop performs with 2060 corrections per second. High sensitivity of the wavefront sensor allows significant improvement in the image quality, even for faint guide stars down to $R = 18 \,\mathrm{mag}$. The FWHM of stellar images in a globular cluster was measured to derive an estimation of the isoplanatic angle and was found nearly constant out to $30''$ from the guide star, indicating that the height of the effective turbulent layer of that particular night was less than 1.8 km. The on-going upgrade plans for a fivefold increase in the number of control elements and for the installation of a laser guide AO system are described.

Null Steering with Element Failures Using Partial Controlled Linear Arrays

This paper deals with re-optimizing linear array patterns with multiple wideband null steering when arbitrary element failures occur. Using partial controlled arrays, the re-optimization method is formulated as a minimax problem solved by a linear programming technique. A weighting function is provided to control the relative error along the re-optimized array pattern. The results indicate that only a few elements are needed for the compensation. Furthermore, the suppressed sectors and the SLL can be improved by increasing the number of controlled elements. The results validate the capability of the proposed method to compensate for arbitrary element failures to re-create the multiple wideband nulls.

Design of Partially Controlled Linear Arrays Using Genetic Algorithms

Partially adaptive antennas are very attractive solution to enhance the desired signal and suppress interference, in communication and radar applications, at a minimum cost. A new design technique, based on the genetic algorithm, has been devised, in order to find the minimum number of controlled elements and their locations in a given linear array. The new technique has been used to steer a given number of nulls towards interfering signal directions and simultaneously reduce the number of controlled elements. The technique is demonstrated using 16-element uniform and Chebyshev arrays. The null steering method used in this work is element position perturbations. Results are given for one and four steered nulls. The results demonstrate the capability of the new technique to steer the array nulls while minimizing the number of controlled elements in the array.

Optimum optical limited scan antenna

An optical limited scan antenna system is considered for applications such as spot coverage of a small portion of the earth from a satellite. The optimum criterion relating aperture efficiency, number of control elements, and angular coverage is revisited briefly. The optical scheme advocated utilizes a bootlace aperture lens, a generalized Luneberg lens focused to the near field, and a small array of active elements. The operation of the system is described first in terms of geometrical optics and elementary diffraction principles. The subarray viewpoint is then developed using simplified diffraction concepts. These results form the basis of a design procedure for the synthesis of high performance limited scan systems. An accurate solution necessary for the analysis of small antennas is developed using a modal decomposition and the wave equation. Numerical computations for a case of practical interest verify the expectation of near optimum performance.