Papers by Keyword: Energy

Abstract: Metal injection molding (MIM) feedstock is composed of Cu powder and a complex binder system that consists of PA6, MgSt, and GMS with various solid loading (43-53vol%). Cu powders used are fabricated by gas and water atomization. Powder particle shapes used have spherical and dendritic shapes. Sphericity of particles can be identified by Scanning Electron Microscopy (SEM). A rheology test is used to ensure the optimum solid loading and investigate the influence of particle shape. The pseudo-plastic behavior of all the feedstock is exhibited by decreasing viscosity along with increasing shear rate for all working temperatures. In this study, rheological test result such as viscosity, flow activation energy, and flow behavior index of feedstock indicates that the optimum solid loading was selected as 43 vol%. Both gas and water atomized powders are desirable for MIM feedstock. According to the rheology behavior test, gas-atomized powders with spherical shape has better rheology stability than water-atomized powders with dendritic shape. The proper MIM feedstock was selected to solid loading 43 vol% with gas-atomized powders.

Abstract: The standard textbook analysis of dislocations is generally limited to the case of infinitely straight screw or edge dislocations, which do not exist. This is due to the complexity of the formulas for arbitrary dislocation loops, i.e., Burger’s equation for the displacement field, the Peach-Köhler equation for the stress field and Blin’s equation for the interaction energy, which involve line integrals along the dislocation loop. The integrands are complex, and integration often involves non-elementary functions. Elaboration of the integrands with symbolic mathematical software produces tensor formulas which can be reused at will. By formulating convenient parametric expressions for the configuration studied and using superposition, mathematical software can be used to perform the integrations for arbitrary Burgers vectors. Often, the resulting expressions for the tensorial fields are very long, but they can be easily incorporated as user-defined formulas for plotting, parametric analysis, and incorporation into routines for energy minimisation or the non-linear equations for force equilibrium. The effectiveness of this approach will be illustrated by the example of short straight dislocations, circular dislocations, the interaction between a pileup and dissociated dislocations in the grain boundary, and the nucleation of dislocations at grain boundaries.

Abstract: Body Area Networks (BAN) consists of sensors, microcontrollers interfaced with the wireless transceivers. BAN sensors are implanted or placed on the body's surface which allows for continuous monitoring of patients' health parameters. According to recent studies, BAN is a viable option for an effective transmission of detected parameters to the nearby health care centers. This transmission helps in energy consumption for further better diagnosis. With the advent of machine learning and Internet of Things (IoT), BAN has taken the dimension in achieving the better performance with limited threshold. Although, BANs are light weight implanted nodes, the problem in improving the performance still remains demur for researchers. This paper proposes the edge based BAN which integrates the powerful Bi layered feed forward (BLFF) learning models for efficient data transmission with lower consumption of energy. The proposed model works on the adaptive distance principle of Extreme Learning Machines (ELM) which detects the cluster head BAN network. The extensive experimentation has been carried out to find the consumption of energy in the network. Additionally, the performance of the proposed ELM-BLFF learning model has been compared with the other machine learning models which are integrated in BAN-IoT frameworks. An experimental result demonstrates that the proposed ELM-BLFF model outperforms the traditional learning model with 30% lesser in terms of energy consumption.

Abstract: The manufacture of ceramic brick goes through the stages of raw material extraction, clay homogenization, material conformation, drying and firing. Drying is the phase that needs greater care, as it involves removing part of the moisture from the brick, in order to preserve its quality after process. This work aims to predict heat and mass transfer in the drying of ceramic bricks in oven using computational fluid dynamics. Considering the constant thermophysical properties, a transient three-dimensional mathematical model was used to predict mass and energy transfer between the material and air during the process. Drying simulations at temperature of 100°C were performed with the air flow in the frontal direction to the ceramic brick holes and the results were compared with those obtained for the air flow in the perpendicular direction to the brick holes reported in the literature. It was found that the position of the brick in relation to the direction of air flow inside the oven affected directly the drying and heating kinetics, and the distribution of temperature and moisture content inside the brick. The positioning of the holes in the brick parallel to the direction of the air flow resulted in reduction at the drying time and, consequently, in energy savings in the process, more uniform drying, and improvement in the product quality.

Abstract: The mechanical behaviour of textile structures is one of their most important characteristics as far as their end use is concerned. Textile structures, fabrics, or yarns are often considered as continuous mediums apart from the fact that they are composed of some discrete elements, individual fibres composing yarns and yarns composing fabrics. This is known as the transition scale, a very important lock to be considered, to evaluate the real structure behaviour. In this context, this work presents some simulations of the mechanical behaviour of a fabric where the yarn is a continuum material. Particular attention was paid to simultaneous loading in uniaxial or biaxial extension and shear loadings. The results of numerical simulations, which show the deformed fabric unit cell under multi-load conditions, are coherent with experimental observations and encourage the authors to continue the present work with parametrical and inverse case studies.

Abstract: The article is devoted to the study of the kinetics of packet formation and energy distribution in the process of explosion welding. The results of experimental determination of the components of the total energy balance during explosion welding and their influence on obtaining a given part profile are presented. The kinetics of the package motion during explosion welding with simultaneous formation of a bimetallic billet with a cylindrical profile is shown.

Abstract: One of the critical physical and mechanical properties of metals and alloys is the suitability for abrasive machining. Machining by abrasive tools is the final operation that sets the desired macro-geometry parameters of processed blanks and microgeometry parameters of processed surfaces such as roughness and length of a bearing surface. Abrasive machining determines the most important physical and mechanical parameters of a blank surface layer, i.e. stresses, phase composition, structure. Machinability by abrasive tools depends on the machining performance affected both by the blank material properties and various processing factors. In our previous studies, we proved that during abrasive machining the metal microvolume affected by abrasive grains accumulates energy. This energy is used for metal dispersion and is converted into heat. According to the theoretical studies described herein, one may note the absence of a reliable and scientifically valid method as well as measuring instruments to determine the machinability of metals and alloys by abrasive tools. For this reason, we suggested a method simulating the effect the multiple abrasive grains produce in a grinding wheel, and enabling us to identify machinability of metals and alloys, select the most efficient abrasive materials for machining of the same, and form the basis for development of effective grinding operations.

Abstract: There is the need for the use of biodegradable optical filters. This concept of this work is to solve the problems of electronic waste and enhance spectra filtering in photovoltaic (PV) module. The extract of the Ixora plant was used for this experiment. The extract was doped with 0.05 m of copper. The voltage peak analysis (VPA) was used to analyze the chemical stability of the filter. It was observed that the filter was chemically stable at certain time of the day due to temperature variations on the PV module.

Abstract: The work is devoted to a study of the probable causes of a decrease in joint strength during explosion welding of metals with sharply differing physical and mechanical properties. The influence of kinematic and energy parameters on the structure and strength of the steel-aluminum composite under various conditions of explosive loading is shown.

Abstract: The study of the intermolecular interactions is important to explain the phenomenon occurred on the human body. One of the most important processes that can be studied is the interaction of the peptide with metal ions. In this study, a computational approach was harnessed to predict the interaction and the changes in peptide’s conformation between Cys-Ala peptide which is one of the important amino acids in e-cadherin with some of alkaline earth metal ions. Cys-Ala peptide (Ac-CA-NH₂) was used as a molecular model in this calculation. All the molecular structure involved in the interaction was optimized by density functional theory DFT/M06-2X, and basis set 6-31G** to obtain minimum energy, the interaction energies, and the changes in its conformation. The results showed that the interaction energy of Ac-CA-NH₂ with alkaline earth metal ions from top to bottom based on the Periodic table is getting higher in a row. The interaction energies of Ac-CA-NH₂ with Be²⁺, Mg²⁺ and Ca²⁺ ions are -2.393kcal, -17.489 kcal, and -25.938 kcal respectively. These energies were obtained from the interaction of the peptide with ions in a water solvent. The changes in the peptide's bond length and dihedral angle indicate a conformational change in the Cys-Ala peptide, but it still maintains the trans conformation in its peptide bonds. The results and evaluations of this study may be used for further research considerations and may be applied to enzymes or other peptides that have the Cys-Ala residue.