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Article
Publication date: 1 April 1986

Michal Polácek

In the course of development of human communities towards industrially advanced societies of today, there have been changes not only in economic conditions in the majority of…

Abstract

In the course of development of human communities towards industrially advanced societies of today, there have been changes not only in economic conditions in the majority of fields of human activity but also in the ways of providing for food, which went hand in hand with changes in living conditions. Large‐scale industrial production has brought about major changes in the way of life of the population. The development of industrial agglomerations results in a growing number of city dwellers, most of whom have no chance of producing foodstuffs of their own in kind. The distance between residential and industrial areas has been growing, the number of employed women has risen considerably. These are but a few factors affecting the way of boarding, particularly in households.

Details

The Tourist Review, vol. 41 no. 4
Type: Research Article
ISSN: 0251-3102

Article
Publication date: 1 April 1991

K. Horio and H. Yanai

I‐V characteristics of GaAs n‐i‐n structures are calculated by considering impact ionization of carriers. Impact ionization at reverse‐biased n‐i junction becomes a cause of steep…

Abstract

I‐V characteristics of GaAs n‐i‐n structures are calculated by considering impact ionization of carriers. Impact ionization at reverse‐biased n‐i junction becomes a cause of steep current rise when an acceptor density in the i‐layer is high. It is shown that an optimum acceptor density exists to keep a good isolation. Photoconduction transients of GaAs n‐i‐n structures are also simulated, and are shown to be strongly affected by existence of n‐i junctions.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 10 no. 4
Type: Research Article
ISSN: 0332-1649

Article
Publication date: 1 January 1992

Tamasz Zoodzinski

In the paper the optimization procedure of a direct current motor with a hybrid excitation has been presented. The excitation system consists of a shunt field winding disposed…

Abstract

In the paper the optimization procedure of a direct current motor with a hybrid excitation has been presented. The excitation system consists of a shunt field winding disposed around field pole and permanent magnet, both acting in parallel. The field distribution in motor for various magnet and field pole dimensions has been determined using finite element method. The flux linkage with the armature winding has been computed. Demagnetizing effect of armature current was taken into account. The optimal permanent magnet and the field pole dimensions, ensuring minimum total cost of purchase and work during assumed period of time were calculated. Motor characteristics e.g. rated torque, rated current, speed regulation limit were used as constraints. In worked up algorithm and computer program Carroll internal penalty function method was used. Some basic suggestions tor design of optimal hybrid excited dc motors with parallel permanent magnet and electromagnetic excitation are given.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 11 no. 1
Type: Research Article
ISSN: 0332-1649

Abstract

Details

Mathematical and Economic Theory of Road Pricing
Type: Book
ISBN: 978-0-08-045671-3

Book part
Publication date: 1 January 2005

Lan Xia and Kent B. Monroe

Abstract

Details

Review of Marketing Research
Type: Book
ISBN: 978-0-85724-723-0

Abstract

Details

Review of Marketing Research
Type: Book
ISBN: 978-0-7656-1305-9

Article
Publication date: 15 September 2022

Natiq Yaseen Taha Al-Menahlawi, Mohammad Reza Khoshravan Azar, Tajbakhsh Navid Chakherlou and Hussein Al-Bugharbee

The purpose of this study is a numerical simulation and an analytical analysis about the low-velocity impact on a functionally graded porous plate with porosity distribution in…

Abstract

Purpose

The purpose of this study is a numerical simulation and an analytical analysis about the low-velocity impact on a functionally graded porous plate with porosity distribution in the thickness direction. In this article, polymethyl methacrylate is used for matrix, and single-walled carbon nanotube (CNTs) (10,10) with consideration agglomeration sizes and lumping of CNT inside the agglomerations is applied for reinforcement.

Design/methodology/approach

In analytical formulation, the non-linear Hertz contact law is applied for interaction between projectile and plate surface. High-order shear deformation plate theory is developed, and energy of the system for impactor and plate is written. The governing equations are derived using Ritz method and Lagrange equations and are solved using the fourth-order Runge–Kutta method. Also, ABAQUS finite element model of functionally graded porous plate with all edges simply supported and reinforced by CNT under low-velocity impact is simulated and is compared with those is achieved in the present analytical approach.

Findings

In parametric studies, the influence of porosity distribution patterns include uniform, non-uniform symmetric and non-uniform asymmetric on the histories of contact force and impactor displacement of simply supported plate reinforced by CNT are presented. Eventually, the effects of porosity coefficient, impactor initial velocity, impactor radius and CNTs lumping inside agglomerations for non-uniform symmetric distribution patterns are discussed in impact event in detail.

Originality/value

In this paper, the effect of combination of polymethyl methacrylate and CNTs with consideration agglomeration sizes and lumping of CNTs inside the agglomerations in the form of a functionally graded porous plate is studied in the problem of low-velocity impact analysis.

Open Access
Article
Publication date: 8 August 2022

Gopal Shruthi and Murugan Suvinthra

The purpose of this paper is to study large deviations for the solution processes of a stochastic equation incorporated with the effects of nonlocal condition.

Abstract

Purpose

The purpose of this paper is to study large deviations for the solution processes of a stochastic equation incorporated with the effects of nonlocal condition.

Design/methodology/approach

A weak convergence approach is adopted to establish the Laplace principle, which is same as the large deviation principle in a Polish space. The sufficient condition for any family of solutions to satisfy the Laplace principle formulated by Budhiraja and Dupuis is used in this work.

Findings

Freidlin–Wentzell type large deviation principle holds good for the solution processes of the stochastic functional integral equation with nonlocal condition.

Originality/value

The asymptotic exponential decay rate of the solution processes of the considered equation towards its deterministic counterpart can be estimated using the established results.

Details

Arab Journal of Mathematical Sciences, vol. 30 no. 1
Type: Research Article
ISSN: 1319-5166

Keywords

Article
Publication date: 17 June 2021

Alok Kumar Mishra, Vaithiyanathan D., Yogesh Pal and Baljit Kaur

This work is proposed for low power energy-efficient applications like laptops, mobile phones, and palmtops. In this study, P-channel metal–oxide–semiconductor (PMOS)’s are used…

Abstract

Purpose

This work is proposed for low power energy-efficient applications like laptops, mobile phones, and palmtops. In this study, P-channel metal–oxide–semiconductor (PMOS)’s are used as access transistor in 7 transistors (7 T) Static Random Access Memory (SRAM) cell, and the theoretical Static Noise Margin (SNM) analysis for the proposed cell is also performed. A cell is designed using 7 T which consists of 4 PMOS and 3 NMOS. In this paper write and hold SNM is addressed and read SNM is also calculated for the proposed 7 T SRAM cell.

Design/methodology/approach

The authors have replaced N-channel metal–oxide–semiconductor (NMOS) access transistors with the PMOS access transistors, which results in proper data line recovery and provides the desired coupling. An error is likely to occur, if the read operation is performed too often probably by using the NMOS pass gate. It results in an improper recovery of the data line. Instead, by using PMOS as a pass gate, the time required for read operation can be brought down. As we know the mobility (µ) of the PMOS transistor is low, so the authors have used this property into the proposed design. When a low signal is applied to its control gate, the PMOS transistor come up with the desired coupling, when working as a pass gate.

Findings

Feedback switched transistor is used in the proposed circuit, which plays an important role in the write operation. This transistor is in OFF state and PMOS’s work as access transistor, when the proposed cell operating in read mode. This helps in the reduction of power. This work is simulated using UMC 40 nm technology node in the cadence virtuoso environment. The simulated result shows that, write power saving of 51.54% and 61.17%, hold power saving of 25.68% and 48.93% when compared with reported 7 T and 6 T, respectively.

Originality/value

The proposed 7 T SRAM cell provides proper data line recovery at a lower voltage when PMOS works as the access transistor. Power consumption is very less in this technique and it is best suitable for low power applications.

Details

Circuit World, vol. 48 no. 3
Type: Research Article
ISSN: 0305-6120

Keywords

Article
Publication date: 13 November 2018

Xuchun Ren and Sharif Rahman

This paper aims to present a new method, named as augmented polynomial dimensional decomposition (PDD) method, for robust design optimization (RDO) and reliability-based design…

Abstract

Purpose

This paper aims to present a new method, named as augmented polynomial dimensional decomposition (PDD) method, for robust design optimization (RDO) and reliability-based design optimization (RBDO) subject to mixed design variables comprising both distributional and structural design variables.

Design/methodology/approach

The method involves a new augmented PDD of a high-dimensional stochastic response for statistical moments and reliability analyses; an integration of the augmented PDD, score functions, and finite-difference approximation for calculating the sensitivities of the first two moments and the failure probability with respect to distributional and structural design variables; and standard gradient-based optimization algorithms.

Findings

New closed-form formulae are presented for the design sensitivities of moments that are simultaneously determined along with the moments. A finite-difference approximation integrated with the embedded Monte Carlo simulation of the augmented PDD is put forward for design sensitivities of the failure probability.

Originality/value

In conjunction with the multi-point, single-step design process, the new method provides an efficient means to solve a general stochastic design problem entailing mixed design variables with a large design space. Numerical results, including a three-hole bracket design, indicate that the proposed methods provide accurate and computationally efficient sensitivity estimates and optimal solutions for RDO and RBDO problems.

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