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A new design of turbogenerator's stator core is being proposed involving the nonmagnetic and nonconducting high‐strength material shells. It is expected to enhance the machine's reliability by reducing laminations shift and the extra losses due to eddy currents. The electromagnetic properties of the proposed design are being studied by using a simplified 2‐D anisotropic multi‐layer theory.

In the paper a comparison between the analytical and numerical method of no‐load computation will be made taking into account the initial hypothesis and computational effort face to the concrete obtainable results. It is concluded that the reduced fixed‐mesh FEM analysis of the induction motors is very suitable for no‐load computation because it relates directly to the well known equivalent circuit parameters. The symmetry of the machine allows for the computation only on a small part of the magnetic circuit so that the time of computation can be reduced even when a relatively fine mesh is used. However, for the optimal design of the motor it appears that analytical methods are very suitable owing to the simplicity and accuracy of the design.

Tool steel (AISI D3) is a preferred material for industrial usage. Some of the typical applications of D3 tool steel are blanking and forming dies, forming rolls, press tools and punches bushes. It is used under conditions where high resistance to wear or to abrasion is required and also for resistance to heavy pressure rather than to sudden shock is desirable. It is a high carbon and high chromium steel. Therefore, wire electric discharge machining (WEDM) is used to machine this tool steel. The paper aims to discuss these issues.

The present experimental investigation evaluates the influence of cryogenically treated wires on material removal rate (MRR) and surface roughness (SR) for machining of AISI D3 steel using the WEDM process. Two important process responses MRR and SR have been studied as a function of four different control parameters, namely pulse width, time between two pulses, wire mechanical tension and wire feed rate.

It was found that pulse width was the most significant parameter which affects the MRR and SR. Better surface finish was obtained with cryogenically treated zinc coated wire than brass wire.

The review of the literature indicates that there is limited published work on the effect of machining parameters in WEDM in cryogenic treated wires. Therefore, in this research work, it was decided to evaluate the effect of cryogenically treated wires on WEDM.

This paper aims to present a new method for the approximate solution of two-dimensional nonlinear Volterra–Fredholm partial integro-differential equations with boundary conditions using two-dimensional Chebyshev wavelets.

For this purpose, an operational matrix of product and integration of the cross-product and differentiation are introduced that essentially of Chebyshev wavelets. The use of these operational matrices simplifies considerably the structure of the computation used for a set of the algebraic system has been obtained by using the collocation points and solved.

Theorem for convergence analysis and some illustrative examples of using the presented method to show the validity, efficiency, high accuracy and applicability of the proposed technique. Some figures are plotted to demonstrate the error analysis of the proposed scheme.

This paper uses operational matrices of two-dimensional Chebyshev wavelets and helps to obtain high accuracy of the method.

This paper gives a bibliographical review of the finite element methods (FEMs) applied to the analysis of ceramics and glass materials. The bibliography at the end of the paper contains references to papers, conference proceedings and theses/dissertations on the subject that were published between 1977‐1998. The following topics are included: ceramics – material and mechanical properties in general, ceramic coatings and joining problems, ceramic composites, ferrites, piezoceramics, ceramic tools and machining, material processing simulations, fracture mechanics and damage, applications of ceramic/composites in engineering; glass – material and mechanical properties in general, glass fiber composites, material processing simulations, fracture mechanics and damage, and applications of glasses in engineering.

Regional civilizations have existed for more than 5,000 years. Each has evolved from primitive, social and political systems into much more complex ones to meet the challenges of historical ages and successive world civilizations (Yakovets, 2000). In the third millennium, regional civilizations face a new challenge – globalization and post-industrial world civilization.

International trade and its effects on the environment are increasingly discussed both in academia and by policymakers. To counter negative effects of international trade on the environment, so called environmental provisions have been integrated in trade agreements aimed at businesses and economies. However, as both the intent and effectiveness of these provisions are controversial, this paper aims to provide an overview of the current state of research and identified key factors influencing their effectiveness.

The authors conduct a systematic literature review of 44 papers on the effects of environmental provisions in international trade agreements on the environmental performance of businesses, as well as economies from 1992 to mid-2024.

The integration of environmental provisions into trade agreements generally has positive effects on the environment while their effectiveness is influenced by their design and several boundary conditions. Alongside the importance of effective enforcement mechanisms, reputation concerns of businesses and lobbyism are discussed as intermediary factors in the design and impact of environmental provisions.

The insights can benefit policymakers to optimize future environmental provisions and advance the effectiveness of policies aimed at balancing the effects of trade liberalization with environmental protection.

Social sustainability is increasingly relevant for creating more sustainable trade policy while societal mechanisms seem to be an adequate tool to ensure effective enforcement of ecological provisions.

To the best of the authors’ knowledge, this review is the first of its kind to provide a systematic overview of the literature on the effectiveness of environmental provisions that combines the micro-level of businesses and macro-level of economies, although the importance for trade in general and environmental protection, in particular, has been recognized in the academic literature.

This paper aims to report an insightful portable microfluidic system for rapid and selective sensing of Hg²⁺ in the picomolar (pM) concentration using microcantilever-based piezoresistive sensor. The detection time for various laboratory-based techniques is generally 12–24 h. The majority of modules used in the proposed platform are battery oriented; therefore, they are portable and handy to carry-out on-field investigations.

In this study, the authors have incorporated the benefit of three technologies, i.e. thin-film, nanoparticles (NPs) and micro-electro-mechanical systems, to selectively capture the Hg²⁺ at the pM concentration. The morphology and topography of the proposed sensor are characterized using field emission scanning electron microscopy and verification of the experimental results using energy dispersive X-ray.

The proposed portable microfluidic system is able to perform the detection in 5 min with a limit of detection (LOD) of 0.163 ng (0.81 pM/mL) for Hg²⁺, which perfectly describes its excellent performance over other reported techniques.

A microcantilever-based technology is perfect for on-site detection, and a LOD of 0.163 ng (0.81 pM/mL) is outstanding compared to other techniques, but the fabrication of microcantilever sensor is complex.

Many researchers used NPs for heavy metal ions sensing, but the excess usage and industrialization of NPs are rapidly expanding harmful consequences on the human life and nature. Also, the LOD of the NPs-based method is limited to nanomolar concentration. The suggested microfluidic system used the benefit of thin-film and microcantilever devices to provide advancement over the NPs-based approach and it has a selective sensing in pM concentration.

Lack of progress advancing labour provisions in multilateral trade instruments has led some countries to develop their own labour chapters in bilateral and plurilateral trade agreements. This study aims to track the evolution of 25 years of labour chapters in Canadian trade agreements.

Modelled on Hoekman (1995), the authors present a novel index using the International Labour Organization’s (ILO) core labour standards to compare and evaluate ambition and enforcement in Canada’s labour chapters.

The quality of Canada’s labour chapters has steadily improved from 1994 to 2020, with scores rising from 46 to 91 out of 100. In addition, Canada has used its negotiating leverage to encourage partners with weak labour regimes to make improvements. Yet, the highest quality chapters were achieved with trade partners similar to Canada, and those chapters have not pushed either party to improve their own domestic labour regimes. The authors discuss the limits of the ILO standards for addressing contemporary debates about labour and trade.

The authors’ assessment provides the first empirical evidence to demonstrate that Canada’s labour chapters have evolved over time, and that the origins of this evolution predate the Liberal government’s progressive trade agenda by several decades. The authors also suggest that Canada’s “middle road” compromise on ambition versus enforceability may increase the relevance of the index for research on other middle powers and potentially countries in the global south.

The purpose of this paper is to review recent advances in wire bonding of low‐k devices.

Dozens of journal and conference articles published in 2005‐2008 are reviewed.

The paper finds that many articles have discussed and analysed problems/challenges such as bond pad metal peeling/lift, non‐sticking on pad, decreased bonding strength and lower wire‐bond assembly yield. The paper discusses the articles' solutions to the problems and recent findings/developments in wire bonding of low‐k devices.

Because of the page limitation, only brief discussions are given in this paper. Further reading is needed for more details.

The paper attempts to provide an introduction to recent developments and the trends in wire bonding of low‐k devices. With the references provided, readers may explore more deeply by reading the original articles.