Viscoelastic initially stressed microbeam heated by an intense pulse laser via photo-thermoelasticity with two-phase lag

This work aims to assess the response of viscoelastic Kelvin–Voigt microscale beams under initial stress. The microbeam is photostimulated by the light emitted by an intense picosecond pulsed laser. The photothermal elasticity model with dual-phase lags, the plasma wave equation and Euler–Bernoulli beam theory are utilized to construct the system equations governing the thermoelastic vibrations of microbeams. Using the Laplace transform technique, the problem is solved analytically and expressions are provided for the distributions of photothermal fields. Taking aluminum as a numerical example, the effect of the pulsed laser duration coefficient, viscoelasticity constants and initial stress on photothermal vibrations has been studied. In addition, a comparison has been made between different models of photo-thermoelasticity to validate the results of the current model. Photo-microdynamic systems might be monolithically integrated on aluminum microbeams using microsurface processing technology as a result of this research.

Unified and non-ideal switch model for analysis of switching circuits

Purpose This paper aims to propose a new unified and non-ideal switch model for analysis of switching circuits. Design/methodology/approach The model has a single unified structure that includes all possible states (on, off) of the switches. The analysis with the proposed switch model requires only one topology and uses the single system equation regardless of states of switches. Moreover, to improve accuracy, the model contains the on-state resistance and capacitive effect of switches. The system equations and the states of switches are updated by control variables, used in the model. Findings There are no restrictions on circuit topology and switch connections. Switches can be internally and externally controlled. The non-ideal nature of the model allows the switch to be modeled more realistically and eliminates the drawbacks of the ideal switch concept. After modeling with the proposed switch model, a linear circuit is obtained. Two examples related to switching circuits are included into the study. The results confirm the accuracy of the model. Originality/value This paper contributes a different switch model for analysis of switching converters to the literature. The main advantage of the model is that it has a unified and non-ideal property. With the proposed switch model, the transient events, like voltage spikes and high-frequency noises, caused by inductor and capacitor elements at switching instants can be observed properly.

New Method of Materials Flow Calculation for Double-String SLCI Type Cement Plant (Part 2: Suspension Preheater and Calciners)

In many industries, energy auditing is important as the basis for controlling processes and designing additional equipment or modifying an existing plant. However, it requires detailed data of the materials flow, which often cannot be determined easily by direct measurement due to high-temperature limitations. This paper presents the second part of an integrated study to perform energy auditing in a separate line and in-line calciners (SLC-I) type cement plant. The second part of this study, as presented in this paper, focused on the materials flow calculation for eight separate cyclones and two calciners. The least square method was employed for solving the obtained overdetermined system equations. Using the operation data from Part 1 of the study, calculation of the detailed materials flow in each cyclone was executed. The results showed that the separation efficiency of cyclones 1A, 2A, 3A, 4A and 1B, 2B, 3B, 4B was 93.86%, 89.80%, 84.41%, 81.98% and 93.96%, 88.70%, 88.53%, 80.72% respectively and the estimated calcination percentage of kiln feed coming out of the ILC and the SLC was 85.3% and 56.3%, respectively. These values are impossible to be measured directly in the cyclones and calciners during plant operation.

Investigation of the Required Discreteness of Interpolation Movement Parameters in Cyber-physical Systems

Improving the accuracy, reliability, and performance of cyber-physical systems such as high-speed machining, laser cutting, welding and cladding etc. is one of the most pressing challenges in modern industry. CNC system carries out data processing and significantly affect on accuracy of operation such equipment. The paper considers the problem of controlled axes motion differential characteristics data processing in the internal representation of the discrete space of the CNC system. Equations for determining the required discreteness of the differential characteristics position and resolution, such as the speed, acceleration, and jerk are proposed. For the most widely used CNC equipment specific discreteness and resolution values have been determined.

New Method of Materials Flow Calculation for Double-String SLCI Type Cement Plant (Part 1: The Whole Clinker Plant)

Materials flow values are instrumental in many industries for controlling and simulating processes, designing new equipment as well as modifying existing plants. They are sometimes impossible to determine by direct measurement in an operating plant due to the very high temperatures. This study attempted to overcome the difficulties associated with this measurement by proposing a new method to calculate materials flow of a double-string suspension preheater type of cement plant with separate line and in-line calciners (SLC-I), with heat balance error less than 1%. This study was divided into two sequential parts, with the first part presented in this paper. The methodology of the first part was to solve the conservation law of the main clinker plant equipment, supported by Bogue’s equation, the heat of calcination, and the thermodynamic properties of the related materials. The least-square method was employed for solving the overdetermined system equations obtained in the second part. The results of the first part were: the ratio of heat formation to specific heat consumption was 52.13% (> 50%), and the gas exhausted from the plant yielded more than 117 MW heat equivalent, which can potentially be recovered for electricity production.

Soft Computing Paradigms to Find the Numerical Solutions of a Nonlinear Influenza Disease Model

The aim of this work is to present the numerical results of the influenza disease nonlinear system using the feed forward artificial neural networks (ANNs) along with the optimization of the combination of global and local search schemes. The genetic algorithm (GA) and active-set method (ASM), i.e., GA-ASM, are implemented as global and local search schemes. The mathematical nonlinear influenza disease system is dependent of four classes, susceptible S(u), infected I(u), recovered R(u) and cross-immune individuals C(u). For the solutions of these classes based on influenza disease system, the design of an objective function is presented using these differential system equations and its corresponding initial conditions. The optimization of this objective function is using the hybrid computing combination of GA-ASM for solving all classes of the influenza disease nonlinear system. The obtained numerical results will be compared by the Adams numerical results to check the authenticity of the designed ANN-GA-ASM. In addition, the designed approach through statistical based operators shows the consistency and stability for solving the influenza disease nonlinear system.

Estimation of the virtual masses of a large unconventional airship based on purely analytical method to aid in the preliminary design

Purpose This paper presents preliminary results of the modeling of a large autonomous quad-rotor airship, with flying wing shape. This airship is supposed to be a flexible body. This study promotes an entirely analytical methodology with some assumptions. In this study and as first assumption, the shape of the careen is supposed to be an elliptic cone. To retrieve the velocity potential shapes, this paper solved the Laplace’s equation by using the sphero-conal coordinates. This leads to the Lamé’s equations. The whole system equations governing the interaction of air–structure, including the boundary conditions, is solved in an analytical setting. Design/methodology/approach This paper opted for a modeling and determination of the added masses of a flexible airship by an analytical method illustrated by a comparison with a geometric method. This analytical method includes the study of complex functions which are the Lamé functions. Findings This paper provides an analytical way to estimate an aerodynamic phenomenon which acts on the airship and in particular on its envelope and known as the phenomenon of added masses or virtual masses, as well as the means of defining it and the calculation analytically for the case of the flexible airship. Research limitations/implications Considering that the calculation of the added masses is very difficult and the numerical methods increase the number of degrees of freedom, the analytical method established in this paper has become a solution of calculations of these virtual masses. Practical implications This paper includes an application for determining the added masses of a new generation MC500 airship. Originality/value This paper allows defining an analytical method which determines the added masses of an airship, which helps the automation engineer to develop a control strategy to stabilize this airship.

Human Movement Recognition in Dancesport Video Images Based on Chaotic System Equations

This paper presents an in-depth study and analysis of human action recognition in dancesport video images through chaotic system equations. A novel fractional-order chaotic system model with hidden multistability is constructed. Since this fractional-order chaotic system has no equilibrium point, the equilibrium point stability analysis is not required. The effect of system parameters on the multistability characteristics of the fractional-order chaotic system is investigated in depth by using the control variable method and nonlinear dynamic tools. In addition, the system has a special property of offset incremental control, which makes the system more widely and practically useful in engineering applications. Finally, circuit simulation experiments and hardware circuit experiments are conducted for the fractional-order chaotic system, and the results are consistent with the corresponding theoretical analysis. The system architecture of the mobile augmented reality-based ethnic dynamic art display system is designed, and the system architecture adopts a hierarchical design. The experimental results show that the design method of the mobile augmented reality-based dynamic art display system proposed in this thesis can meet the purpose of expanding the ways of dancesport display, and the system designed in this thesis is customizable and the synthesized images have a high sense of realism.