The present study has been taken up to emphasize the role of the hybridization process for optimizing a given reinforced concrete (RC) frame. Although various primary techniques have been hybrid in the past with varying degree of success, the effect of hybridization of enhanced versions of standard optimization techniques has found little attention. The focus of the current study is to see if it is possible to maintain and carry the positive effects of enhanced versions of two different techniques while using their hybrid algorithms. For this purpose, enhanced versions of standard particle swarm optimization (PSO) and a standard gravitational search algorithm (GSA), were considered for optimizing an RC frame. The enhanced version of PSO involves its democratization by considering all good and bad experiences of the particles, whereas the enhanced version of the GSA is made self-adaptive by considering a specific range for certain parameters, like the gravitational constant and a set of agents with the best fitness values. The optimization process, being iterative in nature, has been coded in C++. The analysis and design procedure is based on the specifications of Indian codes. Two distinct advantages of enhanced versions of standard PSO and GSA, namely, better capability to escape from local optima and a faster convergence rate, have been tested for the hybrid algorithm. The entire formulation for optimal cost design of a frame includes the cost of beams and columns. The variables of each element of structural frame have been considered as continuous and rounded off appropriately to consider practical limitations. An example has also been considered to emphasize the validity of this optimum design procedure.
The process of enrichment in a jig has usually been described and analysed using particle density as a separation feature. However, a degree of particle loosening in the jig bed is affected by, inter alia, the terminal particle free settling velocity which in turn is affected by the size, density and shape of a particle. Therefore, the terminal particle settling velocity clearly characterises the feed transferred to a jig for the enrichment process. Taking the comprehensive particle geometric (particle size and shape) and physical properties (particle density) into account comes down to the calculation of the terminal particle settling velocity. The terminal particle settling velocity is therefore a complex separation feature which comprises three basic particle features (particle density, size and shape). This paper compares the effects of enrichment of coal fines in a jig, for two cases: when the commonly applied particle density is separation feature and for the particle settling velocity. Particle settling velocities were calculated in the selected three particle size fractions: –3.15+2.00, –10.00+8.00 and –20.00+16.00 mm based on the industrial testing of a jig for coal fines and detailed laboratory tests consisting in determining particle density, projective diameter and volume and dynamic particle shape coefficient. The calculated and drawn partition curves for two variants, i.e. when particle density and particle settling velocity were taken into account as the separation argument in selected particle size fractions, allowed to calculate and compare separation precision indicator. With the use of a statistical test, the assumption on the independence of random variables of the distribution of components included in the distribution of the particle settling velocity as a separation feature during enrichment in a jig was verified.
Safety and operation efficiency of the particle accelerators strongly depend on the quality of the supplied electric current and is affected by the electric properties of all elements of the circuit. In this paper the capacitance of the superconducting bus-bars applied in the cryogenic by-pass line for the SIS100 particle accelerator at FAIR is analysed. The unit capacitance of the bus-bars is calculated numerically and found experimentally. A 2D numerical model of a cross-section of the cable is applied. The capacitance is found with three methods. The stored energy, electric displacement field and charge gathered on the surfaces of the device are calculated and analysed. The obtained values are consistent. Experimental measurements are performed using the resonance method. The measuring system is undamped using a negative conductance converter. Small discrepancies are ob- served between numerical and experimental results. The obtained values are within the requirements of the accelerator design.
The influence of wrong information about transition and measurement models on estimation quality has been presented in the paper. Two methods of a particle filter, with and without the Population Monte Carlo modification, and also the extended and unscented Kalman filters methods have been compared. A small 5-bus power system has been used in simulations, which have been performed based on one data set, and this data set has been chosen from among 100 different – to draw the most general conclusions. Based on the obtained results it has been found that for the particle filter methods the implementation of the slightly higher standard deviation than the true value, usually increases the estimation quality. For the Kalman filters methods it has been concluded that optimal values of variances are equal to the true values.
This paper presents the results of experimental drum granulation of silica flour with the use of wetting liquids with different values of surface tension. Additionally, different liquid jet breakup and different residual moisture of the bed were applied in the tests. The process was conducted periodically in two stages: wetting and proper granulation, during which no liquid was supplied to the bed. The condition of the granulated material after the period of wetting (particle size distribution and moisture of separate fractions) and a change in the particle size distribution during the further conduct of the process (granulation kinetics) were determined.
Water is a strategic material. Recycling is an important component of balancing its use. Deep-bed filtration is an inexpensive purification method and seems to be very effective in spreading water recovery. Good filter designs, such as the fibrous filter, have high separation efficiency, low resistance for the up-flowing fluid and high retention capacity. However, one of the substantial problems of this process is the biofouling of the filter. Biofouling causes clogging and greatly reduces the life of the filter. Therefore, the melt-blown technique was used for the formation of novel antibacterial fibrous filters. Such filters are made of polypropylene composites with zinc oxide and silver nanoparticles on the fiber surface. These components act as inhibitors of bacterial growth in the filter and were tested in laboratory and full scale experiments. Antibacterial/bacteriostatic tests were performed on Petri dishes with E. coli and B. subtilis. Full scale experiments were performed on natural river water, which contained abiotic particles and mutualistic bacteria. The filter performance at industrial scale conditions was measured using a particle counter, a flow cytometer and a confocal microscope. The results of the experiments indicate a significant improvement of the composite filter performance compared to the regular fibrous filter. The differences were mostly due to a reduction in the biofouling effect.
The micro-Particle Image Velocimetry (micro-PIV) was used to measure flow velocities in micro-channels
in two passive micromixers: a microfluidic Venturi mixer and a microfluidic spiral mixer, both preceded
by standard “Y” micromixers. The micro-devices were made of borosilicate glass, with micro-engineering
techniques dedicated to micro-PIV measurements. The obtained velocity profiles show differences in the
flow structure in both cases. The micro-PIV enables understanding the micro-flow phenomena and can help
to increase reproducibility of micromixers in mass production.
In manufacturing industries, the selection of machine parameters is a very complicated task in a time-bound manner. The process parameters play a primary role in confirming the quality, low cost of manufacturing, high productivity, and provide the source for sustainable machining. This paper explores the milling behavior of MWCNT/epoxy nanocomposites to attain the parametric conditions having lower surface roughness (Ra) and higher materials removal rate (MRR). Milling is considered as an indispensable process employed to acquire highly accurate and precise slots. Particle swarm optimization (PSO) is very trendy among the nature-stimulated metaheuristic method used for the optimization of varying constraints. This article uses the non-dominated PSO algorithm to optimize the milling parameters, namely, MWCNT weight% (Wt.), spindle speed (N), feed rate (F), and depth of cut (D). The first setting confirmatory test demonstrates the value of Ra and MRR that are found as 1:62 μm and 5.69 mm3/min, respectively and for the second set, the obtained values of Ra and MRR are 3.74 μm and 22.83 mm3/min respectively. The Pareto set allows the manufacturer to determine the optimal setting depending on their application need. The outcomes of the proposed algorithm offer new criteria to control the milling parameters for high efficiency.
Clinker burning process has a decisive influence on energy consumption and the cost of cement production. A new problem is to use the process of decarbonization of alternative fuels from waste. These issues are particularly important in the introduction of a two-stage combustion of fuel in a rotary kiln without the typical reactor-decarbonizator. This work presents results of numerical studies on thermal-hydraulic phenomena in the riser chamber, which will be designed to burn fuel in the system where combustion air is supplied separately from the clinker cooler. The mathematical model is based on a combination of two methods of motion description: Euler description for the gas phase and Lagrange description for particles. Heat transfer between particles of raw material and gas was added to the numerical calculations. The main aim of the research was finding the correct fractional distribution of particles. For assumed particle distribution on the first stage of work, authors noted that all particles were carried away by the upper outlet to the preheater tower, what is not corresponding to the results of experimental studies. The obtained results of calculations can be the basis for further optimization of the design and operating conditions in the riser chamber with the implementation of the system.
Simultaneous measurements of the indoor and outdoor particle mass (PM) and particle number (PN) concentrations as well as the air temperature, relative humidity (RH), and CO2 concentrations have been conducted in 6 occupied (L) and unoccupied (V) classrooms in 3 secondary schools in Lublin, Poland, in the heating (H) and summer (S) seasons. The schools were located in residential areas where the majority of private houses are heated by means of coal-burning stoves. The ratios of the average particle concentrations in occupied and unoccupied classrooms (L/V) were higher during the heating season measurements. The ratios of the average particle concentrations during the measurements in the heating and summer seasons (H/S) were higher in occupied classrooms. In both seasons the average PM and PN concentrations amounted to 239 μg/m3 and 7.4×103/cm3 in the occupied classrooms, and to 76 μg/m3 and 5.4×103/cm3 in the unoccupied classrooms, respectively. The particle exposures experienced by students were higher in the monitored classrooms than outdoors and were on average about 50% higher in the heating than in the summer season. A positive correlation between mass concentrations of coarse particles and indoor air temperature, RH and CO2 concentrations in both seasons was observed. The concentrations of fine particles were negatively correlated with the indoor air parameters in the heating season, and positively correlated in the summer season.
Particle Image Velocimetry is getting more and more often the method of choice not only for visualization of turbulent mass flows in fluid mechanics, but also in linear and non-linear acoustics for non-intrusive visualization of acoustic particle velocity. Particle Image Velocimetry with low sampling rate (about 15Hz) can be applied to visualize the acoustic field using the acquisition synchronized to the excitation signal. Such phase-locked PIV technique is described and used in experiments presented in the paper. The main goal of research was to propose a model of PIV systematic error due to non-zero time interval between acquisitions of two images of the examined sound field seeded with tracer particles, what affects the measurement of complex acoustic signals. Usefulness of the presented model is confirmed experimentally. The correction procedure, based on the proposed model, applied to measurement data increases the accuracy of acoustic particle velocity field visualization and creates new possibilities in observation of sound fields excited with multi-tonal or band-limited noise signals.
This paper presents practical capabilities of a system for ceramic mould quality forecasting implemented in an industrial plant (foundry). The main assumption of the developed solution is the possibility of eliminating a faulty mould from a production line just before the casting operation. It allows relative savings to be achieved, and faulty moulds, and thus faulty castings occurrence in the production cycle to be minimized. The numerical computing module (the DEFFEM 3D package), based on the smoothed particle hydrodynamics (SPH) is one of key solutions of the system implemented. Due to very long computing times, the developed numerical module cannot be effectively used to carry out multi-variant simulations of mould filling and solidification of castings. To utilize the benefits from application of the CUDA architecture to improve the computing effectiveness, the most time consuming procedure of looking for neighbours was parallelized (cell-linked list method). The study is complemented by examples of results of performance tests and their analysis.
This paper investigates whether a quantum computer can efficiently simulate the non-elastic scattering of the Schrödinger particle on a stationary excitable shield. The return of the shield to the ground state is caused by photon emission. An algorithm is presented for simulating the time evolution of such a process, implemented on standard two-input gates. The algorithm is used for the computation of elastic and non-elastic scattering probabilities. The results obtained by our algorithm are compared with those obtained using the standard Cayley’s method.