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This article deals with analyzing the phase–frequency response of commande robuste d'ordre non-entier approximations of fractional-order differentiators. More precisely, an algebraic tight upper bound is derived for the phase of the approximations obtained from the commande robuste d'ordre non-entier method. Then, some applications for this achievement are discussed in the viewpoint of control systems analysis. These applications include usefulness of the obtained upper bound in stability preservation analysis during the commande robuste d'ordre non-entier–based approximation process and applicability of such a bound in finding necessary or sufficient conditions for test of positive... 

Despite the huge potential, value predictors have not been used in modern processors. This is partially due to the complex structures associated with such predictors. In this paper we study value predictors and investigate solutions to reduce storage requirements while imposing negligible coverage cost. Our solutions build on the observation that conventional value predictors do not utilize storage efficiently as they allocate too much space for small and frequently appearing values. We measure data width requirement and entropy in a subset of predictor resources and show that values stored in predictors show limited sizes and very small entropy. We exploit this behavior and suggest... 

In this work, we study a kind of manipulation process during which we deal with active objects. An active object is a concept covering a variety of objects that are not rigid and need to be controlled during the manipulation process. Here, we use a multi-link mechanism with active motors (actuator) as the object and a series of simple planar manipulators to perform the manipulation process. Dynamic, control, motion planning, and stability at the presence of impact are the most important challenges in this work  

A method for singularity reduction in a triangular 3-UPS mechanism is discussed. This mechanism usually has singularity near the origin. Changing the active joint angle can arrive at a suitable workspace near the origin without any singularity. Moreover, a 4-UPS mechanism, based on adding one additional leg to the 3-UPS mechanism, has a larger singular free workspace. Moreover, force analysis of two different mechanisms shows a reasonable and consistent force distribution between the different actuators. Singular free workspace is one of the characteristics which makes this mechanism ideal for haptic applications  

We have applied our recent approach to study the quantum-information properties of the anisotropic s=1/2 Heisenberg chain. We have investigated the underlying quantum-information properties such as the evolution of concurrence, entanglement entropy, nonanalytic behaviors, and the scaling close to the quantum critical point of the model. Both the concurrence and the entanglement entropy develop two saturated values after enough iterations of the renormalization of coupling constants. These values are associated with the two different phases, i.e., Néel and spin liquid phases. The nonanalytic behavior comes from the divergence of the first derivative of both measures of entanglement as the... 

We have combined the idea of renormalization group and quantum-information theory. We have shown how the entanglement or concurrence evolve as the size of the system becomes large, i.e., the finite size scaling is obtained. Moreover, we introduce how the renormalization-group approach can be implemented to obtain the quantum-information properties of a many-body system. We have obtained the concurrence as a measure of entanglement, its derivatives and their scaling behavior versus the size of system for the one-dimensional Ising model in transverse field. We have found that the derivative of concurrence between two blocks each containing half of the system size diverges at the critical point... 

The effects of using frequency-domain approximation in numerical simulation of fractional-order systems are analytically studied. The main aim in the study is to determine the number, location and stability property of the equilibriums in a fractional-order system and its frequency-based approximating counterpart. The comparison shows that the original fractional-order system and its frequency-based approximation may differ from each other in some or all issues considered in the study. Unfortunately, these differences can lead to wrong consequences in some special cases such as detecting chaos in the fractional-order systems. It is shown that using the frequency-domain approximation methods... 

This paper presents anti-synchronization of chaos between two different chaotic systems using active control method. The proposed technique is applied to achieve chaos antisynchronization for the Lu and Rössler dynamical systems. Numerical simulations are implemented to verify the results. COPYRIGHT © ENFORMATIKA  

A new central differencing finite volume scheme is investigated for solution of unsteady hydraulic problems as water hammer in pipe systems. Special time stepping procedure similar to Runge-Kutta algorithm is used to stabilize this second order scheme. It is monotonized by adding dissipative terms including second and fourth derivatives of the conserved variables, with coefficients proportional to derivatives of pressure or volumetric flow, which keeps the second order of accuracy in smooth flow regions. The one-dimensional unsteady incompressible equations are solved for a water hammer situation, and results are compared to existing analytical solutions. Results are also compared with... 

This article describes an automatic reactor power control system for VVER-1000 reactor and reports simulation analysis results for a typical daily load follow operation. The associated reactor control algorithm is called `mode G' that uses a heavy-worth bank (H-bank) dedicated to axial power shape control and the light-gray banks (G-banks) for reactor power change and reactivity compensation. The simulation results for daily load follow operation in three burnup states of first cycle illustrate that the load follow capability of VVER-1000 reactors using this algorithm will be improved  

Operational capabilities are used in resource based view in strategic management literature to explain how the difference in performing similar activities results in heterogeneity between firms. In order to advance our understanding of this concept, using a system metaphor, we try to shape a framework for micro-level analysis of operational capabilities. Following two stages of holism and focus for identifying system boundaries through looking related literatures, we propose knowledge, skills and tools as general micro elements of operational capabilities in form domain. Using Dependency Structure Matrix (DSM), we finally synthesize our conceptual framework to capture interactions of... 

The reliable design, planning, and operation of power systems are of paramount importance for providing reliable services to customers. This article reviews the different aspects of power system reliability, ranging from planning to operation. Standard benchmarks employed for power system studies are reviewed according to nearly 2,500 IEEE journal papers from 1986 to early 2019. Our overview provides the pros and cons of existing test systems, implying the lack of appropriate benchmarks for future power system studies, including renewable resources and modern technologies. Furthermore, this article presents requirements for updating and modifying the benchmarks for modern power systems... 

This article deals with analyzing the phase–frequency response of commande robuste d'ordre non-entier approximations of fractional-order differentiators. More precisely, an algebraic tight upper bound is derived for the phase of the approximations obtained from the commande robuste d'ordre non-entier method. Then, some applications for this achievement are discussed in the viewpoint of control systems analysis. These applications include usefulness of the obtained upper bound in stability preservation analysis during the commande robuste d'ordre non-entier–based approximation process and applicability of such a bound in finding necessary or sufficient conditions for test of positive... 

Multi-agent systems (MAS) is a solution to the nowadays encountered problems, which have the characteristics such as distributiveness, dynamism and the need to adaptation, robustness, efficiency, and reusability. This paper proposed a solution to multi-agent credit assignment problem. The contribution is to equip the critic agent (who is responsible for distributing reinforcements among agents) with learning capability. Some criteria are used to propose an inner feedback to the critic. Results of simulation show the applicability of the method to a task, which has the characteristic that the agent has to decide from a large set of actions. The research is a preliminary step to more in-depth... 

Feed-forward is one of the main methods for linearization of microwave power amplifiers. Although the complexity of the system is increased, the level of inter-modulation rejection (IMR) of a feed-forward system can be improved using a multi-loop configuration. Predicting the IMR of such a system is of prime importance. A new analytical approach in modeling a multi-loop feed-forward system for predicting the linearization performance of the system is presented. The first loop of the multi-loop system is substituted by an equivalent amplifier model and then the reduced system as a new feed-forward system is evaluated. The predicted IMR values are verified using the ADS simulator and a MATLAB... 

In this paper, the role and importance of the machine vision systems in the industrial applications are described. First understanding of the vision in terms of a universal concept is explained. System design methodology is discussed and a generic machine vision model is reported. Such a machine includes systems and sub-systems, which of course depend on the type of applications and required tasks. In general, expected functions from a vision machine are the exploitation and imposition of the environmental constraint of a scene, the capturing of the images, analysis of those captured images, recognition of certain objects and features within each image, and the initiation of subsequent... 

This paper presents a designed system for measuring three dimensions (height, width and length) of steel billets during molding process. The system has been equipped with a GigaEthernet camera and an industrial computer (IPC). The billet is moved in front of the inspection system with an external moving mechanism. Image processing techniques and calibration are used to measure dimensions from the succeeding single view images. ©2006 IEEE  

This paper explores design and implementation of an event-based simulator namely DBMSS for analyzing concurrency protocols in database systems. In the design of DBMSS we interested in event-based approach to create a real world with variety range of event possibilities. DBMSS is explored in the context of the development of a complex simulator for simulating real world conditions and provide an event-based environment to test and evaluate concurrency protocols in database systems. First we discuss the architecture of DBMSS and use it to provide arrival transactions to test and evaluate concurrency protocols in database system. We present the comparison of 4 concurrency protocols in variety... 

The use of adaptive feedforward controllers has proven to be a very successful strategy for controlling noise and vibration in a variety of applications. One reason is that the feedforward controller is an open loop controller, which can be designed to cancel the undesired noise in one position with any accuracy. However, the feedforward controller requires an input signal, called a reference signal, correlated to the noise source. As a consequence, a single reference controller can only reduce noise radiated from a single noise source. In many applications, there is a need to attenuate noise produced by several noise sources. In this paper, three different structures, single, modulating and... 

In this paper, we propose a processor allocation mechanism for run-time assignment of a set of communicating tasks of input applications onto the processing nodes of a Chip Multiprocessor (CMP), when the arrival order and execution lifetime of the input applications are not known a priori. This mechanism targets the on-chip communication and aims to reduce the power and latency of the NoC employed as the communication infrastructure. In this work, we benefit from the advantages of non-contiguous processor allocation mechanisms, by allowing the tasks of the input application mapped onto disjoint regions (sub-meshes) and then virtually connecting them by bypassing the router pipeline stages of...