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The purpose of this study is to suppress the temperature rise of high voltage wall bushing metal plate.

First, the authors built a model of a traditional metal plate and got the magnetic field intensity distribution by FEA tools. Optimized according to the magnetic field intensity distribution, the authors slot the traditional metal plate and embed permanent magnets in the slot. Finally, the authors got the temperature distribution diagrams of the above three cases at different current levels by FEA tools.

Slotted metal plate is beneficial to suppress magnetic induction intensity, but the improvement of the magnetic induction intensity uniformity is not obvious. The method of embedding a permanent magnet in a slotted metal plate can optimize the magnitude and uniformity of the magnetic induction intensity in the metal plate. The larger the current passing through the metal plate, the better the temperature suppression effect of the slotted metal plate and the slotted metal plate embedded in the permanent magnet.

The effect of structural factors, slotting plate and setting permanent magnets on slots on the temperature of supporting plate is studied. The paper proposes two methods, slotting metal panels and embedding permanent magnet metal panels, to solve the problems of eddy current loss and high calorific value of the panel, which is of great significance to the safety of the grid equipment.

The purpose of this paper is to present a novel and applied method for optimum designing of plate-finned heat exchanger network. Considering the total annual cost as the objective function, a network of plate-finned heat exchanger is designed and optimized.

Accurate evaluation of plate-finned heat exchanger networks depends on different fin types with 10 different geometrical parameters of heat exchangers. In this study, fin numbers are considered as the main decision variables and geometrical parameters of fins are considered as the secondary decision variables. The algorithm applies heat transfer and pressure drop coefficients correction method and differential evolution (DE) algorithm to obtain the optimum results. In this paper, optimization and minimization of the total annual cost of heat exchanger network is considered as the objective function.

In this study, a novel and applied method for optimum designing of plate-finned heat exchanger network is presented. The comprehensive algorithm is applied into a case study and the results are obtained for both counter-flow and cross-flow plate-finned heat exchangers. The total annual cost and total area of the network with counter-flow heat exchangers were 12.5% and 23.27%, respectively, smaller than the corresponding values of the network with cross-flow heat exchanger.

In this paper, a reliable method is used to design, optimize parameters and the economic optimization of heat exchanger network. Taking into account the importance of plate-finned heat exchangers in industrial applications and the complexity in their geometry, the DE methodology is adopted to obtain an optimal geometric configuration. The total annual cost is chosen as the objective function. Applying this technique to a case study illustrates its capability to accurate design plate-finned heat exchangers to improve the objective function of the heat exchanger network from the economic viewpoint with the design of details.

This paper discusses how the grain size of plated copper changes as time passes by observing the copper surface topography after surface treatment with a roughening agent. This paper also discusses how the time until the recrystallization terminates depends on the amount and type of plating additives as well as current density. The results agree with the known mechanism of grain growth. As a result of our experiments, the best process to gain the optimal surface topography is proposed. We firmly believe that this paper will contribute to the improvement in quality control of the copper surface treatment process, which will in turn lead to the fabrication of PCBs and plastic packages with higher reliability.

The purpose of this paper is to present elastic buckling behaviour of simply supported and clamped thin rectangular isotropic plates having central circular cutouts subjected to uniaxial partial edge compression. Analysis is carried out for four different kinds of partial edge compression and it is extended to study the effect of aspect ratio of plate on buckling load.

A finite element method technique is used in the current work to solve the buckling problem of plate using eight node quadrilateral element and plate kinematics based on first order shear deformation theory. Results obtained from finite element analysis are first validated for isotropic square plates, without cutouts, subjected to uniaxial partial edge compression with some earlier published literature.

From the current work it is concluded that the buckling strength of square plates is highly influenced by partial edge compression, as compared to plate subjected to uniform edge compression; but with increase in aspect ratio, influence of partial edge compression on plate buckling load decreases.

This paper usefully shows how partial edge compression of plates affects the buckling strength of plate having circular cutouts. Generally, simply supported plates subjected uniaxial partial edge compression of Type I and Type III are found to be stronger than plates subjected to partial edge compression Type II and Type IV, respectively.

Electroless plating is an important process in printed circuit board and electronics manufacturing but typically requires temperatures of 70‐95°C to give a suitable deposition rate. This is becoming problematic in industry due to the rising price of energy and is a major contribution to production costs. Previous studies have noted beneficial effects of ultrasonic irradiation upon electroless plating processes and it has been reported that sonication can increase the plating rate and produce changes to the chemical and physical properties of the deposited coating. The purpose of this paper is to reduce the operating temperature of an electroless nickel bath by introducing ultrasound to the process.

The deposition rate of an electroless nickel solution was determined by two techniques. In the first method, test coupons were plated in an electroless nickel solution at temperatures ranging from 50‐90°C and the plating rate was calculated by weight gain. In the second approach the mixed potential (and hence the current density at the mixed potential) was determined by electrochemical analysis of the anodic and cathodic reactions. In both cases the plating rate was found with and without the application of an ultrasonic field (20 kHz). The electroless nickel deposits obtained in the plating tests were also analysed to determine the phosphorus content, microhardness and brightness.

The plating rates under ultrasonic agitation were always higher than under “silent” conditions. Most importantly, considering the objectives of this study, the deposition rate under sonication at 70°C was significantly higher than that found with mechanical agitation at 90°C. In addition, the results indicated that the deposits produced in an ultrasonic field had consistently lower phosphorus content, higher microhardness and were brighter than those prepared in an electroless nickel bath that was not sonicated.

Although previous work has been performed on the effect of ultrasound on electroless plating, all these studies have been carried out at the normal operating temperature of the electroless process. In this paper, ultrasound has been applied at temperatures well below those normally used in electroless nickel deposition to determine whether sonication can enable low temperature electroless plating.

A finite element formulation for flexure of isotropic plates based on a recent refined theory is developed. The refined theory incorporates effects of transverse shear, transverse normal stress and transverse normal strain. The Galerkin finite element method was used to develop the finite element equations for both plate bending and inplane problems. The performance of the proposed finite element model was evaluated by solving problems of uniformly loaded thick plates with different support conditions. The results of the present formulation are compared with Mindlin/Reissner and elasticity solutions.

An adaptive mesh refinement procedure is used in static plate bending finite element analysis to study the edge effects in Mindlin—Reissner plates.

A formulation has been developed for thermo‐elastoviscoplastic finite element analyses of continuous fibre‐reinforced composite plates subject to bending loading using a generalized continuum mechanics approach. Such an approach is used to model the non‐homogeneity in a composite, which is constituted by fibres embedded in a matrix material. The present formulation computes the respective stresses occurring in each constituent so that the respective yield criterion and flow rule of each constituent may be used if there is a material yielding in any constituent. Thermo‐elastic deformation of fibre and thermo‐elastoviscoplastic deformation of matrix are considered in the present study because the yield strength of fibre is substantially higher than that of matrix in many cases. Both constituents are assumed to be isotropic so that the von‐Mises yield criterion may be used for viscoplastic yielding of matrix. As numerical examples, a parametric study is performed for thermo‐elastoviscoplastic deformations of laminated composite plates subject to thermal bending loads.

Fibre‐reinforced plastic (FRP) materials have been recognised as new innovative materials for concrete rehabilitation and retrofit. Since concrete is poor in tension, a beam without any form of reinforcement will fail when subjected to a relatively small tensile load. Therefore, the bonding of FRP plate to reinforced concrete (RC) structure is an effective solution to increase its overall strength. In such plated beams, tensile forces develop in the bonded plate and these have to be transferred to the original beam via interfacial shear and normal stresses. Consequently, the debonding of FRP plates bonded to reinforced concrete beams is believed to be initiated by the stress concentration in the adhesive layer. Accurate predictions of the interfacial stresses are prerequisite for designing against debonding failures. In the present analysis, a simple theoretical model to estimate shear and normal stresses is proposed, including the variation in FRP plate fibre orientation. The solution shows significant shear and normal stresses concentration at the plates end. A parametrical study is carried out to show the effects of some design variables, e.g., thickness of adhesive layer and FRP plate, and the distance from support to cut ‐ off end of bonded plates.

This paper aims to study the effect of external glass fibre reinforced polymer (GFRP) plates on the flexural and shear behaviour of structurally deficient reinforced concrete (RC) beams, a total of ten 180mm×250mm×2,500mm beams, including over‐designed, unplated under‐designed and plated under‐designed, were tested under four‐point bending condition. Experimental results indicate that the use of GFRP plates enhances the strength and deformation capacity of RC beams by altering their failure modes. Application of side plates on shear‐deficient RC beams appears to be more effective than using bottom plates on flexure‐deficient RC beams. However, without any improvement of concrete compressive capacity, additional shear capacities provided to the beams under the action of side plates increase the likelihood of beam failure by concrete crushing. Simultaneous use of bottom and side plates on flexural‐ and shear‐deficient RC beams may result in reduced deflection.