Th. Haug, P. Magnani, B. Bressel, H.‐J. Grapentin and H. Meyer
Today modern epoxy base materials for printed circuit board production are designed with properties which ensure high dimensional stability, resistance to chemical action, and…
Abstract
Today modern epoxy base materials for printed circuit board production are designed with properties which ensure high dimensional stability, resistance to chemical action, and increased glass transition temperature, in order to meet the stringent demands now encountered in electronics use. Polyfunctional epoxy resins and the appropriate hardener/accelerator compositions are in widespread, effective use in the design of superior laminates. The quality of the through‐hole plating for holes drilled in these improved materials will depend on various parameters, including those covered by three main complexes: base material, mechanical processing, and chemical processes used for treatment of the drilled hole. Special attention is paid in this paper to the resin recession phenomenon in terms of processing parameters.
Mariusz Pyrz and Jadwiga Zawidzka
The potential of two distinct approaches applied to the truss discrete optimization problem is presented in the paper. The sequential discrete optimization method SDO (which is a…
Abstract
The potential of two distinct approaches applied to the truss discrete optimization problem is presented in the paper. The sequential discrete optimization method SDO (which is a deterministic procedure, using heuristics based on the idea of fully stressed truss design) and the genetic algorithm GA (a stochastic search method, inspired by the natural evolution model) are compared. The minimum weight design of truss structures subjected to stress and displacement constraints is investigated, including the case of multiple load conditions. The discrete design variables are areas of members, selected from a finite catalogue of available sections. Benchmark 2D and 3D problems are presented in numerical examples. The effectiveness of two approaches is discussed. The improvements of both algorithms and GA integrating the results of SDO method are proposed. They enable us to accelerate the convergence, diminish the number of structural analyses and guide to refined “near optimal” solutions.
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Nikolay Gospodinov, Ana María Herrera and Elena Pesavento
This article investigates the robustness of impulse response estimators to near unit roots and near cointegration in vector autoregressive (VAR) models. We compare estimators…
Abstract
This article investigates the robustness of impulse response estimators to near unit roots and near cointegration in vector autoregressive (VAR) models. We compare estimators based on VAR specifications determined by pretests for unit roots and cointegration as well as unrestricted VAR specifications in levels. Our main finding is that the impulse response estimators obtained from the levels specification tend to be most robust when the magnitude of the roots is not known. The pretest specification works well only when the restrictions imposed by the model are satisfied. Its performance deteriorates even for small deviations from the exact unit root for one or more model variables. We illustrate the practical relevance of our results through simulation examples and an empirical application.
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Buildings are the condensation of the national, ethnic, or cultural identity. They are also the specific materialized form of the national social systems, folk customs, and…
Abstract
Buildings are the condensation of the national, ethnic, or cultural identity. They are also the specific materialized form of the national social systems, folk customs, and ideologies. Architectural design and philosophy constitute an isomorphic relationship with each other. This study focuses on the Chinese traditional philosophy. Using Kuanzhai Alley in Chengdu as an example, philosophical expressions, such as “holistic thinking,” “group form layout,” “heaven and man,” “yin–yang and the five elements,” “ancient architecture design,” “good” aesthetic concepts, and “conformal”rationalism, are discussed from the aspects of the selection of the environment, spatial layout, architectural symbol, planning, and design significance. The traditional architectural forms and types are analyzed and interpreted based on the Chinese traditional philosophy. The role of the ancient Chinese philosophy in the Designs of Chinese Buildings is summarized. Traditional ideas on Chinese architecture should be recognized from the aspect of philosophy to propose a new design direction for developing modern Chinese architectural designs.
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Ralf Östermark and Rune Höglund
The power and size of five cointegration tests, the ADF‐, Zˆα‐, ECM‐, SW‐, and JJ‐statistics, are evaluated in some large‐scale Monte Carlo simulations, when the underlying system…
Abstract
The power and size of five cointegration tests, the ADF‐, Zˆα‐, ECM‐, SW‐, and JJ‐statistics, are evaluated in some large‐scale Monte Carlo simulations, when the underlying system is subjected to regime shifts. Following the suggestion by Gregory and Hansen, selects the minimum value for the shift‐corrected statistics evaluated over a set of tentative break points for the regime shifts. The performance of these statistics is compared to the corresponding ordinary statistics in conditions of regime shifts. The results show that no test uniformly outperforms the others in terms of power in the parameter space we have used.
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Ilaria Boncori and Kristin Samantha Williams
This article explores memory work and storytelling as an organising tool through family histories, offering theoretical and methodological implications and extending existing…
Abstract
Purpose
This article explores memory work and storytelling as an organising tool through family histories, offering theoretical and methodological implications and extending existing conceptualisations of memory work as a feminist method. This approach is termed as impressionist memory work.
Design/methodology/approach
To illustrate impressionistic memory work in action, the article presents two family histories set during Second World War and invite the reader to engage in the “undoing” of these stories and dominant ways of knowing through storytelling. This method challenges the taken-for-granted roles, plots and detail of family histories to uncover the obscured or silenced stories within, together with feminine, affective and embodied subjectivities, marginalisation and social inequalities.
Findings
This study argues that impressionistic memory work as a feminist method can challenge the silencing and gendering of experiences in co-constructed and co-interpreted narratives (both formal and informal ones).
Originality/value
This study shows that engagement with impressionistic memory work can challenge taken-for-granted stories with prominent male actors and masculine narratives to reveal the female actors and feminine narratives within. This approach will offer a more inclusive perspective on family histories and deeper engagement with the marginalised or neglected actors and aspects of our histories.
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Atul Kumar Sahu, Prabhu M. and K.T. Vigneswara Rao
The occurrence of COVID-19 has impacted the wide-reaching dimensions of manufacturing, materials, procurement, management, etc., and has loaded disruptions in the wide range of…
Abstract
Purpose
The occurrence of COVID-19 has impacted the wide-reaching dimensions of manufacturing, materials, procurement, management, etc., and has loaded disruptions in the wide range of supply chain (SC) activities. The impact of COVID-19 has twisted supplier performance and influenced stakeholders’ thinking towards selecting supplier sources and making strategic sourcing decision for convinced arrangement of construction management (CM) resources. Nowadays, suppliers are intently evaluated by stakeholders in post-COVID-19 phase to induce agile availability of CM resources. Accordingly, this paper aims to demonstrate competent CM dimensions under post COVID-19 scenario for ease managing construction projects by the stakeholders.
Design/methodology/approach
The authors have implicated Grey Sets Theory along with decision-making trial and evaluation laboratory (DEMATEL) technique for understanding significant outcomes. Varieties of diverse decision aspects responsible for strategically influencing supplier sourcing decision is projected under post COVID-19 scenario for handling construction projects by the stakeholders.
Findings
This study investigated sustainable construction management dimensions (SCMD) at the stage of resource deliveries and client aspirations under post COVID-19 situation. The study demonstrated “Lead time” as the most crucial, “Product Range” as the second and “Customers dealings and relationship” as the third crucial aspect considering by the stakeholders for selecting supplier sources based on the attainment of performance score of 0.1338, 0.1273 and 0.1268, respectively. It is found that high lead time stimulates the stakeholders to divert their orders to other competent supplier sources holding a low degree of lead time as compared.
Research limitations/implications
The present study rollovers its existence by serving critical thinking, conceptual modelling, criteria identification and evaluation under CM domain for drafting effectual strategies by the suppliers. The study investigated the impact of COVID-19 on stakeholders’ decision-making and enlisted SCMD that strategically stimulated them in choosing supplier sourcing decision.
Originality/value
The present study realizes the insights of stakeholders in the post COVID-19 scenario related to the supplier sources based on performance score. The study quantified sustainable supplier attribute for construction work and practices. The study analysed the expectations of the stakeholders purchasing different varieties of construction materials from supplier sources for civil works in the post COVID-19 scenario.