AUTOMATED SYNTHESIS OF BROADBAND MATCHING AND FILTERING DEVICES

2018 ◽  
pp. 48-52
Author(s):  
S. V. Popov ◽  
G. N. Devyatkov

When designing radioelectronic devices, that are included in the composition of various systems, it is important to solve broadband matching problem and filtering problem. However, usually these problems are separated and not considered together. Moreover, the synthesis of filters does not take into account the behavior of impedances of the generator and the load in the stopbands. The solution of the complex problem is actual, since it allows expanding the functionality of the device, which can greatly simplify the construction of the radio engineering product. It should be noted that in the known literature solution of this problem in such a formulation is not considered. The aim of the work is to develop a synthesis method and algorithm of broadband devices that connect arbitrary immitances of the generator and the load, and these devices should perform simultaneously functions of both matching and filtering in reactive lumped electric element base and in distributed electric element base, limited only by transmission lines with T-waves. In this paper, a two-stage automated method of synthesis presented here stage allows at the first to adequately find a good initial solution to the posed problem (determining structure and parameters of the broadband matching and filtering quadrupole), in the second stage this approach allows to find the optimal solution to the complex problem, taking into account the constraints on physical and circuit realizability. In this work, the synthesis of broadband matching and filtering devices in lumped and distributed electrical element basis is carried out, and these devices connect complex impedances of the source and the load. The characteristics of the devices obtained after the synthesis show that the solution of the complex problem of matching and filtering gives a significant improvement in filtering properties with small losses in the level of transmitted power.

Relieving congestion is a major technical issue in power transmission systems. In this paper, simultaneous placement of Thyristor controlled series capacitors (TCSC) and Voltage source converter based distribution generators (VSC-DG) are used for relieving congestion, minimize system cost and maintain the system in secure state. The system has been analyzed in three stages: (i) first stage, the congestions are made in different transmission network by overload and line outages, (ii) second stage, relieving congestion of transmission lines by using TCSC and VSCDG, where these devices are placed simultaneously at their optimal locations, (iii) comparative cost analysis is done between normal and congested systems. The proposed approach is tested on the 62-bus Indian power system network. The optimal solution of the test systems are obtained by genetic algorithm method and its solutions are compared with primal linear programming. All the results are validated through Power World Simulator and GA toolbox in MATLAB.


2018 ◽  
pp. 40-47
Author(s):  
D. I. Volkhin ◽  
G. N. Devyatkov

The development of a new class of broadband matching devices, including active impedance transformers, with the possibility of correcting the phase response is an actual task at present. Synthesis of a broadband active impedance transformer with a phase response corresponding to a second-order lattice X-section in a distributed elemental basis based on the previously presented method for the synthesis of broadband matching devices with predetermined phase response is considered in this paper. As a result of synthesis, the y-matrix of the broadband transforming two-port network is obtained. The functions of its own parameters represented in the form of Foster. Applying various conditions of circuit realizability in the synthesis process, we obtained structures convenient for realization on microwave on regular transmission lines, one of which is investigated at various parameters of a given phase response. As a result of the research, it is found that the structure has a wide ability to reproduce the phase response of a second-order lattice X-section with different parameters, and also reproduce the linear phase response characteristic while maintaining an acceptable level of the power conversion coefficient in a given frequency band. Thus, the efficiency of the previously proposed method of synthesis of broadband matching devices with predetermined phase response is demonstrated, and also the possibilities of active impedance transformers on regular transmission lines are shown.


2021 ◽  
Vol 2 (2) ◽  
Author(s):  
Daniel Vert ◽  
Renaud Sirdey ◽  
Stéphane Louise

AbstractThis paper experimentally investigates the behavior of analog quantum computers as commercialized by D-Wave when confronted to instances of the maximum cardinality matching problem which is specifically designed to be hard to solve by means of simulated annealing. We benchmark a D-Wave “Washington” (2X) with 1098 operational qubits on various sizes of such instances and observe that for all but the most trivially small of these it fails to obtain an optimal solution. Thus, our results suggest that quantum annealing, at least as implemented in a D-Wave device, falls in the same pitfalls as simulated annealing and hence provides additional evidences suggesting that there exist polynomial-time problems that such a machine cannot solve efficiently to optimality. Additionally, we investigate the extent to which the qubits interconnection topologies explains these latter experimental results. In particular, we provide evidences that the sparsity of these topologies which, as such, lead to QUBO problems of artificially inflated sizes can partly explain the aforementioned disappointing observations. Therefore, this paper hints that denser interconnection topologies are necessary to unleash the potential of the quantum annealing approach.


2014 ◽  
Vol 39 (1) ◽  
pp. 3-16 ◽  
Author(s):  
Enrique Gerstl ◽  
Gur Mosheiov ◽  
Assaf Sarig

Abstract We study a special two-stage flexible flowshop, which consists of several parallel identical machines in the first stage and a single machine in the second stage. We assume identical jobs, and the option of batching, with a required setup time prior to the processing of a new batch. We also consider the option to use only a subset of the available machines. The objective is minimum makespan. A unique optimal solution is introduced, containing the optimal number of machines to be used, the sequence of batch sizes, and the batch schedule. The running time of our proposed solution algorithm is independent of the number of jobs, and linear in the number of machines


2021 ◽  
Author(s):  
Dmitry Moiseevich Olenchikov

Abstract Recently, more and more reservoir flow models are being extended to integrated ones to consider the influence of the surface network on the field development. A serious numerical problem is the handling of constraints in the form of inequalities. It is especially difficult in combination with optimization and automatic control of well and surface equipment. Traditional numerical methods solve the problem iteratively, choosing the operation modes for network elements. Sometimes solution may violate constraints or not be an optimal. The paper proposes a new flexible and relatively efficient method that allows to reliably handle constraints. The idea is to work with entire set of all possible operation modes according to constraints and control capabilities. Let's call this set an operation modes domain (OMD). The problem is solved in two stages. On the first stage (direct course) the OMD are calculated for all network elements from wells to terminal. Constraints are handled by narrowing the OMD. On the second stage (backward course) the optimal solution is chosen from OMD.


2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Marcilio Andrade ◽  
Dermeval Carinhana Jr

Purpose This purpose of this study is to structure complex problems to be solved with greater efficiency, optimising the relationship between root causes (RC) relevance of the problem and utilisation of human resources to treat them, minimising the use of manpower in problem-solving activity and thus contributing to greater productivity within organisations. Design/methodology/approach The authors built an approach under the concepts of theory of constraints and multiattribute and multiobjective decision-making methods that were applied in a real complex problem of the low development of Brazilian space industry, by theoretical perspective. Also, the authors submitted it in a simulation environment to assess in which situations it is successful considering number of problem’s RC, system complexity and number of people in the system. Findings The approach was successful on the real case, finding the optimal relationship between the RC relevance and the number of people involved to treat them. For certain complex problem inputs configurations, simulation results reveal that the approach is reliable obtaining more than 95% chance of success in finding the optimal relationship, when comparing with traditional prioritising methods. Originality/value This approach introduces an unprecedented way to locate and evaluate non-physical constraints within a system, which is used to determine RC relevance, as well as an unprecedented way of defining a single optimal solution for structuring a problem, considering the relevance of RC and the use of human resources. The approach is useful for organisations in general which often need managing complex problems with few resources.


Author(s):  
Arslan Ali Syed ◽  
Irina Gaponova ◽  
Klaus Bogenberger

The majority of transportation problems include optimizing some sort of cost function. These optimization problems are often NP-hard and have an exponential increase in computation time with the increase in the model size. The problem of matching vehicles to passenger requests in ride hailing (RH) contexts typically falls into this category.Metaheuristics are often utilized for such problems with the aim of finding a global optimal solution. However, such algorithms usually include lots of parameters that need to be tuned to obtain a good performance. Typically multiple simulations are run on diverse small size problems and the parameters values that perform the best on average are chosen for subsequent larger simulations.In contrast to the above approach, we propose training a neural network to predict the parameter values that work the best for an instance of the given problem. We show that various features, based on the problem instance and shareability graph statistics, can be used to predict the solution quality of a matching problem in RH services. Consequently, the values corresponding to the best predicted solution can be selected for the actual problem. We study the effectiveness of above described approach for the static assignment of vehicles to passengers in RH services. We utilized the DriveNow data from Bavarian Motor Works (BMW) for generating passenger requests inside Munich, and for the metaheuristic, we used a large neighborhood search (LNS) algorithm combined with a shareability graph.


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