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The transient simulation of integrated circuit has become very expensive in terms of computer time due to increase in the number of transistors in typical simulation. Spectral technique and Chebyshev polynomials offers an efficient alternative algorithm for simulation of integrated circuits. In this paper an automatic formulation of circuit elements and transistor models, built in MOS technology, for analysis using spectral technique is presented. The algorithm is implemented and the simulation is proven to require less computer time than in the case of SPICE or ASTAP

The purpose of this paper is to analyse the dynamic behaviour of an elasto‐plastic sandwich subjected to low velocity impact.

A numerical model is developed with the assumption that the plastic deformation is confined under the contact area. The structure is analyzed using the in‐house finite element code with an appropriate contact law. During the impact progression, two phases (elastic and plastic) related to the impact intensity are considered in the dynamic model. The proportional viscous damping is incorporated in the model. An elasto‐plastic impact algorithm is established to determine the impact force, the sandwich structure displacement and indentation.

The numerical results are validated by experimental dropping weight impact tests. The influences of the impactor radius, the core material variation and the impactor initial velocity on the dynamic behaviour of the impacted structure are studied.

In order to study the low velocity impact problems by considering the caused plastic deformations, a simple numerical elasto‐plastic impact model of sandwich structure is proposed.

Mobile games and ICT-based mixed reality tools offer significant opportunities for tourism. This chapter reviews the existing literature in both these areas, and presents a novel way of combining games and virtual reality into an interpretive tool. As a complex, threatened marine ecosystem, Australia’s Great Barrier Reef faces significant interpretive challenges, and almost no new interpretive tools have been developed over the last 30 years. Here, the authors unpack the stages and interdisciplinary approach required to design the tool and highlight how it might fit within the broader scope of ICT developments in tourism. We outline areas of future research, with a particular focus on how ICT might contribute to making nature-based tourism more sustainable, by finding fun, innovative ways to engage tourists in the conservation of some of our most iconic natural assets.

Introduction: Small- and medium-sized enterprises (SMEs) play a vital role in the economic development of economies by generating job opportunities. Considering their significance, understanding the challenges and skills required in these enterprises becomes essential and timely.

Purpose: This study aims to discuss the limitations and skill gaps faced by SMEs in emerging economies, such as India, Indonesia, Brazil, China, Malaysia, Ghana, Hungary, Saudi Arabia, South Africa, Türkiye, UAE, Iran, Kazakhstan, Türkiye, Zambia, Romania, and Vietnam.

Methodology: The study adopts a systematic review and meta-synthesis approach, utilising a literature review to comprehensively analyse, synthesise, and map the existing literature by identifying overarching themes.

Findings: The study examines the challenges SMEs encounter in emerging economies, including resource scarcity, limited access to credit, inadequate infrastructure, low technology adoption, restricted global market access, and ineffective marketing strategies. There is a notable shortage of skilled labour and development initiatives within SMEs in India even though the country has a sizeable pool of qualified workers. There is a pressing need for additional technical and managerial skills to remain competitive in the market. The findings of this study will assist HR managers in addressing skill shortages among employees in SMEs operating within emerging economies

The purpose of this paper is to deal with the investigation of no-load operation of tubular linear permanent magnet synchronous machines (T-LPMSMs). It is aimed at the prediction of the phase flux linkages, the back-EMF and the cogging force using a position varying magnetic equivalent circuit (MEC).

This study is based on the elaboration and the resolution of the position varying MEC, and the utilization of its results for the prediction of the phase flux linkages, the back-EMF and the cogging force, considering a general topology of T-LPMSMs. Then, a case study is treated with a position varying MEC-based investigation of its no-load features. These are validated by a 2-D finite element analysis (FEA).

It has been found that the developed position varying MEC can be regarded as an accurate tool that requires a low CPU-time.

Beyond the FEA validation, this work should be extended to an experimental one. Moreover, the position varying MEC validity should be extended to load operation in order to enable the prediction of the force production capability.

The developed position varying MEC could be suitably used for the pre-design of T-LPMSMs. These are currently given an increasing attention in many applications, such as wave energy conversion and free-piston engines.

The paper proposes a position varying MEC for the prediction of the features of T-LPMSMs.

Unemployment is one of the major challenges facing most countries, including Africa as a continent. Seeking how to reduce unemployment, debt, inflation and increase gross domestic product (GDP), foreign direct investment (FDI) and gross capital formation in the continent has been an agenda of governments, policy makers and economists to. This study examines the relationship between economic growth, inflation, debt, FDI, gross capital formation, labor force, population and unemployment in Africa.

An updated panel dataset of 29 African countries was selected from different regions from 1991 to 2019. These countries were selected based on their unemployment, population growth and inflation rates. The Pesaran cross-sectional dependence and panel unit root test (the Dickey–Fuller cross-sectional supplemented and the Im-Pesaran-Shin cross-sectional) were applied. Further, the panel Autoregressive Distributed Lag (ARDL) model (Bounds test) and pooled mean group (PMG) estimator were utilized in this work.

This shows that economic growth, debt, labor force and population have a positive relationship with unemployment in the long run. Therefore, an increase in these variables generates an increase in the selected African countries' unemployment growth. In contrast, inflation, FDI and gross capital formation have a negative relationship with unemployment in the long run, which implies that an increase in these variables reduces unemployment in the selected African countries.

This study has potential limitations because some data from the countries are not up to date and some years are missing from the data.

This study contributes to understanding unemployment and Okun's law in the African economy. This study shows that an increase in economic growth leads to a rise in unemployment, while an increase in inflation leads to a decrease in unemployment.

This paper provides an insight into the major factors that increase and reduces unemployment for government and policy marker to take the adequate measure.

As technological entrepreneurship has distinctive characteristics and needs particular conceptualizations, it is also important to have specific theoretical developments about its technological entrepreneurship. Studying the related domains like entrepreneurship and technology can be helpful in this path; however, their differences should be considered as well. The purpose of this study is to design a model in support of technological entrepreneurship. Since financing is considered as the main restriction on creating and developing technological entrepreneurship, the focus of this study is the research of financial policies of technological entrepreneurship..

This research is from the qualitative point of view and in terms of the purpose of application-development that has been done in the second part. At the first step, Iran’s (IRI) national comprehensive policies have been studied from 1993 to 2020; out of 52 documents, 7 were relevant, of which 38 policies were eventually selected. Then, policy statements were explored, and open coding and categorization has been done through theme analysis approach to attain fundamental themes and organizational themes. In the second step, the themes were extracted in the form of soft research method with the approach of interpretive structural modeling to level the financing policies of technological entrepreneurship in Iran.

The results show that the most important factors influencing financing and entrepreneurship in Iran are increasing the productivity of goods and services, supporting entrepreneurship, increasing the efficiency of monetary policies that are in the first level.

Research limitations include access to upstream documents, strategies, administrative and organizational coordination to study documents.

These findings are very important to scholars, the policymakers and technological entrepreneurship operators in designing their financing strategies. The results show that the most important factors influencing financing and entrepreneurship in Iran are increasing the productivity of goods and services, supporting entrepreneurship, increasing the efficiency of monetary policies.

To the best of the author’s knowledge, this is the first study to explore the explanation and classification of technology-based entrepreneurship financing policies in Iran. Moreover, the findings of this study would prove useful in detailed studies of financing policies in the Middle Eastern countries as well.

Black cumin (Nigella sativa L.) is well known for its strong, hot, peppery taste and has many nutritional, pharmaceutical and traditional therapeutic uses. The aim of this study was to investigate the antioxidant effect of different solvent extracts of black cumin seed to retard lipid and protein oxidation in raw ground pork meat during refrigerated storage (4 ± 1°C) for nine days.

Black cumin extracts (BCEs) were prepared using different solvents, namely, ethanol, water, ethanol:water (60:40) and methanol:hot water (60:40). Extracts were analysed for total phenolic content (TPC), 1,1 diphenyl-2-picrylhydrazil (DPPH) radical scavenging activity and reducing power. Based on the results, water extract (WE) and ethanol–water extract (EHWE) of black cumin were selected and incorporated at 1.5 per cent into freshly minced pork meat and compared with a synthetic antioxidant, butylated hydroxytoluene (BHT; 100 ppm), in retarding lipid and protein oxidation. Treated and control samples were aerobically packed in low-density polyethylene bags for analysis of various parameters (pH, colour and odour score, peroxide, lipid and protein oxidation) during nine-day refrigerated storage study.

Results showed that BCEs had a good amount of TPC (4.4-7.4 mg gallic acid equivalents/g) and also DPPH scavenging activities (33.96-44.23 per cent), with WE and EHWE extracts showing highest reducing power and promising antioxidant capacity. Hence, BCEs (WE and EHWE) incorporated at 1.5 per cent into freshly minced pork meat was tested, compared to BHT (100 ppm) and control samples, in retarding lipid and protein oxidation during storage. In BCE-treated samples, thiobarbituric acid reacting substances, free fatty acids, peroxide, formation of protein carbonyls and off-odour or rancid odour development were lower than control and values were comparable with BHT. Incorporation of BCE did not negatively affect the colour of ground pork.

BCEs (WE and EHWE) at 1.5 per cent inhibited protein and lipid oxidation and it could be exploited commercially as an effective alternative in retarding oxidative deterioration of meat products.

The purpose of this paper is to propose a general model for locating and clamping workpieces of complex geometry with two skewed holes under multiple constraints.

Numerous constraints related to application of the proposed model are discussed as prerequisite to design of fixture solution. Based on theoretical model, a fixture was designed and successfully tested in experimental investigation. Experimental results were also verified using FEM simulations.

This study showed that, opposed to conventional approach, novel solution results in significantly smaller fixture dimensions, while providing greater stability. Insertion of mandrels and supports element sub-assemblies into the workpiece holes significantly increases workpiece stiffness through an increased moment of inertia, while the internal support elements largely diminish the problem of thin wall deformation in the workpiece.

The fixture designed in this case was actually used in industrial application to accommodate a thin-walled casting of gearbox housing, where it proved to be a very stable framework. It can be used in industry without any major readjustments.

According to available literature, this work is the first successful implementation of a fixture solution in which the problem of multiple constraints is solved by attaching centering elements, support sub-assemblies, and other fixture elements to the internal workpiece walls, and then locating them in the second part of the fixture.

The purpose of this paper is to introduce an asymmetric structure of the magnetic equivalent circuit (MEC) for analysis of the linear induction machine (LIM) with an internal short circuit fault.

By applying a proper MEC to the LIM, a generalized relation for the inductance matrix of the machine can be directly determined. To evaluate the proposed model, the stator currents and the air-gap flux with the proposed technique are given and compared to the simulation and experimental results in the healthy and fault conditions.

The LIM is an axial flux machine with a wide range of applications in high-performance drives. Due to a well-tried effect of the first tooth and the last one (the end effect), the performance level of the LIM decreases. Also, the analysis of the linear machines in fault conditions illustrates more complexity compared to the rotary induction machine. However, the MEC is very simple, describing the behavior of the asymmetric electromechanical devices using the magnetic reluctance or the permeance of flux paths.

Using the proposed model, there would be some decrease in the complications of the LIM analysis in the asymmetrical conditions. Moreover, analyzing some of the characteristics of the LIM, such as turn-fault condition, it can be calculated with high accuracy.