In this issue of the Journal we continue with our series of articles describing the current situation of the printed circuit industry in various countries throughout the world and…
Abstract
In this issue of the Journal we continue with our series of articles describing the current situation of the printed circuit industry in various countries throughout the world and as such focus our attention on India. This article has been submitted by Mr. V. Mitter of Hegde & Golay Ltd., Bangalore, India and his co‐operation is gratefully acknowledged.
As miniaturisation reaches new levels with the advent of surface mount technology, the mixed technology of surface mount and through‐hole brings into focus the need for…
Abstract
As miniaturisation reaches new levels with the advent of surface mount technology, the mixed technology of surface mount and through‐hole brings into focus the need for soldermaskless printed circuit boards which can have considerable shelf life before assembly and which can satisfy the new requirements of NTL‐STD‐SOLD for optimum solderability. The ‘weak‐kneed’ hole due to the tin‐copper intermetallic encountered in hot air levelled boards needs to be eliminated. This paper describes a process based on cap layers for terminal and test pads, and a duplex alloy plating of tin, nickel and lead on the outer layers which has several advantages over the currently preferred solder mask over bare copper/selective solder coating process.
Rajini V. and Margaret Amutha W.
The purpose of this paper is to carry out a detailed analysis of two port converter fed by Solar and wind sources during different operational modes by small signal modelling. The…
Abstract
Purpose
The purpose of this paper is to carry out a detailed analysis of two port converter fed by Solar and wind sources during different operational modes by small signal modelling. The converter is fully characterized and simulated using Matlab/Simulink. The voltage and current waveforms along with their corresponding expressions describing the converter operation are presented in detail. Then the DC-averaged equivalent topology is derived using circuit averaging technique. A complete derivation of the power stage transfer functions relevant to the capacitor voltage loop, such as capacitor voltage to solar voltage and inductor current to wind input voltage is obtained.
Design/methodology/approach
Stability analysis is used to analyze the small deviations around the steady-state operating point which helps in modeling the closed loop converter parameters. This paper presents the analysis, modeling and control of two port Cuk-buck converter topology.
Findings
Based on the results, a control strategy is designed to manage the energy flow within the system. A lab-level prototype for Cuk-buck converter with PWM controller is implemented and tested under various input conditions to study the performance of the converter during seasonal changes. The simulation and experimental results showed that effective operation and control strategy of the hybrid power supply system managed to be achieved alongside its feasible outputs.
Practical implications
This analysis can be extended to all power electronic converters and will be useful for the design of controllers.
Social implications
An appropriate control design plays a key role in enhancing the overall performance of the system. Hence, this paper is intended to present in detail the small signal modeling of the Cuk-buck converter along with the control design for all the switching modes.
Originality/value
Though this type of converter topology has been discussed widely in literature, very scarce literature is available related to modeling and control design of the converter. A state-space averaging model of the converter followed by a type-II compensator design is described, and prototype design and experimental results are also presented.
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Climate change has a direct impact on companies. Therefore, the scenario analysis is used to provide companies and stakeholders in this specific sector with forward-looking…
Abstract
Purpose
Climate change has a direct impact on companies. Therefore, the scenario analysis is used to provide companies and stakeholders in this specific sector with forward-looking measures and narratives of the world's future state. This work aims to provide an independent, wide and rigorous literature review on the topics of scenario analysis and climate change, analyzing a large set of referred papers included in economic journals on the Web of Science Clarivate Analytics data source. This review, by means of a mixed approach, can help address new policy strategies and business models.
Design/methodology/approach
The work employs 416 abstracts and relative titles in the field of economics, employing data mining for qualitative variables and performing descriptive statistics and lexicometric measures, similarity analysis and clustering with Reinert's hierarchical method in order to extract knowledge. Furthermore, qualitative content analysis allows for the return of a comprehensive and complete universe of meaning, as well as the analysis of co-occurences.
Findings
Content analysis reveals three main classification clusters and four unknown patterns: model area, risks, emissions and energy and carbon pricing, indicating research directions and limitations through an overview with an extensive reference bibliography. In the research, the prevalent use of quantitative instruments and their limitations emerge, while qualitative instruments are residual for climate change assessment; they also highlight the centrality of transition risk over adaptation measures and the combination of different types of instruments with reference to carbon pricing.
Originality/value
Scenario analysis is a relatively new topic in economics and finance research, and it is under-investigated by the academy. The analysis combines quantitative and qualitative research using text analytics.
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M. De la Sen and C.F. Alastruey
The stability of linear time‐delay systems with point internal delays is difficult to deal with in practice because of the fact that their characteristic equation is usually of…
Abstract
The stability of linear time‐delay systems with point internal delays is difficult to deal with in practice because of the fact that their characteristic equation is usually of transcendent type rather than of polynomial type. This feature causes usually the system to possess an infinite number of poles. In this paper, stability tests for this class of systems are obtained either based on extensions of classical tests applicable to delay‐free systems or on approaches within the framework of two‐dimensional digital filters. Some of those two‐dimensional stability tests are also proved to be useful for stability testing of a common class of linear hybrid systems which involve coupled continuous and digital substates after a slight “ad‐hoc” adaptation of the tests for that situation.
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A. Mitter, J.P. Malhotra and H.T. Jadeja
A modelling approach of gas solid flow, considering different physical phenomenon such as fluid turbulence, particle turbulence and interparticle collision effects are presented…
Abstract
A modelling approach of gas solid flow, considering different physical phenomenon such as fluid turbulence, particle turbulence and interparticle collision effects are presented. The approach is based on the two‐fluid model formulation where both phases are treated as continuum. This implies that the gas phase as well as the particle phase are weighted by their separate volumetric fractions. According to the experimental results and numerical simulations, the inter‐particle collision possesses a significant influence of turbulence level on particle transport properties in gas solid turbulent flow even for dispersed phase volume fraction (α<0.01). Comparisons in predictions have been depicted with inclusion of interparticle collision effect in the equation of particle turbulent kinetic energy and with exclusion of this effect. Experimental research has been conducted in a thermal power plant depicting higher erosion resistance of noncircular square sectioned coal pipe bends in comparison with those with circular cross section, the salient features of the experimental work are presented in this paper. Experiments have been conducted to determine, pressure drop in straight and curved portions of conduits conveying air coal mixtures in a thermal power plant. Validation of this experimental data with numerical predictions have been presented.
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The main aim of this chapter is to discuss the conceptualization of comparative pedagogies within Continental European and Anglophone traditions, and to discuss the importance of…
Abstract
The main aim of this chapter is to discuss the conceptualization of comparative pedagogies within Continental European and Anglophone traditions, and to discuss the importance of comparative pedagogy within the contemporary comparative educational research as such. The chapter opens with the issue of naming and translation of the key terminology, notably pedagogy, comparative pedagogy, and vzgoja (Erziehung in German and vospitanie in Russian) – a concept which implies the teacher’s intentional guidance of children in their moral, personal, social, aesthetical, physical, and spiritual advancement. The chapter presents a brief history of the development of pedagogy as a distinctive science, and proceeds with the discussion on pedagogy’s identity. Due to multifaceted understanding of pedagogy in Continental Europe, the chapter focuses on the academic tradition in Slovenia and wider area of former Yugoslavia. Further, the role of comparison in different contemporary historical periods of pedagogy’s development is explained. The chapter shows that comparative pedagogy has different meanings in different academic traditions. The main difference between that Continental Europe and the Anglophone world is in the knowledge base they built on (pedagogy vs. other social sciences), and the focus they place on endogenous and exogenous factors influencing the nature of education systems and pedagogical processes. The author finally proposes a new definition of comparative pedagogy; a definition which takes pedagogy as its knowledge base, but is also informed with a long tradition of comparative education research based on other social sciences.
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Jeffrey Pomerantz and Gary Marchionini
The purpose of this paper is to present a high‐level investigation of the physical‐conceptual continuum occupied by both digital and physical libraries.
Abstract
Purpose
The purpose of this paper is to present a high‐level investigation of the physical‐conceptual continuum occupied by both digital and physical libraries.
Design/methodology/approach
A framework is provided for thinking about the notions of place and library. The issue of materials and the ideas they represent is considered. Places for people are considered, including issues of people's sense of place in physical and digital spaces. The issue of physical and digital spaces as places for work, collaboration, and community‐building is considered.
Findings
As more digital libraries are built, and as more physical libraries offer electronic access to parts of their collection, two trends are likely to result: the role of the library as a storage space for materials will become decreasingly important; and the role of the library as a space for users, for individual and collaborative work, and as a space for social activity, will become increasingly important.
Research limitations/implications
Digital libraries are unable to fulfill some of the functions of the physical library as physical spaces, but are able to offer functions beyond what the physical library can offer as cognitive spaces.
Practical implications
Areas of likely future development for digital libraries are suggested, as vehicles for enhancing cognitive space by augmenting representations of ideas in materials.
Originality/value
This paper argues that in many ways digital libraries really are places in the conceptual sense, and will continue to broaden and enrich the roles that libraries play in people's lives and in the larger social milieu.
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Christine Mitter and Martin R.W. Hiebl
This paper aims to analyze the role of management accounting in international entrepreneurship. Its role, thus far, has been a neglected topic in research on accounting and…
Abstract
Purpose
This paper aims to analyze the role of management accounting in international entrepreneurship. Its role, thus far, has been a neglected topic in research on accounting and international entrepreneurship, although some quantitative findings indicate the positive influence of management accounting on internationalization capability.
Design/methodology/approach
This paper is based on a multiple case study of Austrian firms and draws on the resource-based view of the firm as well as effectuation/causation logics. Data for this study were collected via semi-structured interviews, press reports, company chronicles, organizational brochures and websites of the analyzed case firms.
Findings
The paper finds that management accounting may indeed serve as a key capability for international entrepreneurship. However, reliance on this capability seems to be contingent on the phase of international entrepreneurship and pathway and mode of internationalization.
Research limitations/implications
The findings add to the accounting literature by showing that the phase as well as the mode and pathway of international entrepreneurship may serve as contingency factors for management accounting, which have been overlooked in the literature. At the same time, they also contribute to the international entrepreneurship literature by offering an initial view on the neglected capability of management accounting.
Originality/value
This is the first study to analyze the role of management accounting in international entrepreneurship.
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THE Funk Gerat 10 equipment is the latest standardized type, and is installed in all the later bombers and reconnaissance machines of the Luftwaffe.