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1 – 10 of 429The purpose of this paper is to describe the use of copper‐substituted nickel manganite thick film and bulk ceramic superstrate on Ag thick film microstrip straight…
Abstract
Purpose
The purpose of this paper is to describe the use of copper‐substituted nickel manganite thick film and bulk ceramic superstrate on Ag thick film microstrip straight resonator (MSR), to modify its response and measure complex permittivity as a function of copper.
Design/methodology/approach
The glass frit free (fritless) copper‐substituted nickel manganite thick films were formulated on alumina substrate by screen printing technique from the powder synthesized by oxalic precursor method. A comparison has been made between the X band response of Ag thick film MSR due to perturbation of bulk and thick film Ni(1−x)CuxMn2O4 (0≤x≤1) ceramic. The shift has been used to measure the permittivity of the ceramic. The dielectric constants obtained by superstrate technique on Ag thick film microstrip component are comparable to those obtained from theoretical calculations.
Findings
The resonance frequency of MSR shifts towards lower frequency due to the presence of Ni(1−x)CuxMn2O4 (0≤x≤1) ceramic as superstrate. The dielectric constant of bulk and thick film match well with the theoretical values. The dielectric constant increases with copper concentration and shows reduction of power gain of MSR. The peak output (power gain) of MSR due to thick film NiMn2O4 increases by 10.19 per cent with decrease in bandwidth and increase in the quality factor with copper concentration.
Originality/value
The superstrate on Ag thick film straight resonator is an efficient tool capable of detecting the composition‐dependent changes in microwave properties of ceramic thick films. These Ni(1−x)CuxMn2O4 ceramic being thermistor materials apart from modifying the response can also be used as power sensors providing cost‐effective miniaturization.
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S.N. Mathad, R.N. Jadhav and Vijaya Puri
The purpose of this paper was to determine the complex permittivity of bismuth strontium manganites (Bi1−xSrxMnO3) in the 8‐12 GHz range by using perturbation of Ag thick…
Abstract
Purpose
The purpose of this paper was to determine the complex permittivity of bismuth strontium manganites (Bi1−xSrxMnO3) in the 8‐12 GHz range by using perturbation of Ag thick film microstrip ring resonator (MSRR) due to superstrate of both bulk and thick film.
Design/methodology/approach
The BSM ceramics were synthesized by simple low cost solid state reaction method and their fritless thick films were fabricated by screen printing technique on alumina substrate. A comparison has been made between the X band response of Ag thick film microstrip ring resonator due to perturbation of bulk and thick film Bi1−xSrxMnO3 ceramic.
Findings
The bulk and thick film superstrate decreases the resonance frequency of MSRR. In this technique even minor change in the properties of superstrate material changes the MSRR response. Variation of strontium content also influences microwave conductivity and penetration depth of bulk and thick films.
Originality/value
The microwave complex permittivity decreases with increase in Sr content in bismuth manganite and it is higher for bulk as compared to its thick films. The superstrate on Ag thick film microstrip ring resonator is an efficient tool capable of detecting the composition dependent changes in microwave properties of ceramic bulk and thick films.
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N. Patil, N.B. Velhal, R. Pawar and Vijaya Puri
The purpose of this article is to study the effect of ferrite content on electric, magnetic and microwave properties of screen-printed y(Ni0.4Co0.2Cd0.4Fe2O4) + (1 …
Abstract
Purpose
The purpose of this article is to study the effect of ferrite content on electric, magnetic and microwave properties of screen-printed y(Ni0.4Co0.2Cd0.4Fe2O4) + (1 − y)Pb(Zr0.52Ti0.48)O3 (y = 0.0, 0.15, 0.30, 0.45, 1.0) thick films on alumina.
Design/methodology/approach
Thick films of ferrite–ferroelectric composite on alumina substrate have been delineated using screen printing technique. The structural analysis was carried out using X-ray diffraction method and scanning electron microscopy. The DC electrical resistivity was measured using the two-probe method. The magnetic measurement was carried out using a vibrating sample magnetometer. Microwave absorption was studied in the 8-18 GHz frequency range by using the vector network analyzer (N5230A). The permittivity in the 8-18 GHz frequency range was measured by using voltage standing wave ratio slotted section method.
Findings
The formation of two individual ferrite–ferroelectric phases in composite thick films was confirmed by the X-ray diffraction patterns. The scanning electron microscope morphologies show the growth of cobalt-substituted nickel cadmium ferrite grains which are well dispersed in lead zirconium titanate matrix. The DC electrical resistivity increases with increase in ferrite content and decreases with increase in temperature. The present ferrite shows ferromagnetic nature and it increases saturation magnetization and coercivity of the composite thick films. Tuning properties are observed in the Ku-band and broadband X-band microwave absorption is observed in the composite thick films. The imaginary part of permittivity increases with an increase in ferrite content, which increases microwave absorption. The real part of microwave permittivity varied from 17 to around 22 with an increase in ferrite content and it decreases with frequency. The microwave conductivity, which increases with an increase in ferrite content, reveals the loss of polaron conduction, which supports the dielectric loss in the microwave region.
Originality/value
Electric, magnetic and microwave properties of screen-printed y(Ni0.4Co0.2Cd0.4Fe2O4) + (1 − y)Pb(Zr0.52Ti0.48)O3 (y = 0.0, 0.15, 0.30, 0.45, 1.0) composite thick films on alumina substrate is reported for the first time.
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Rouhin Deb, Harsh Vardhan Samalia and Santosh Kumar Prusty
Competitive pressure from informal firms has always been a threat to the formal enterprises. However, the strategic choices a firm makes to deal with such competitive…
Abstract
Purpose
Competitive pressure from informal firms has always been a threat to the formal enterprises. However, the strategic choices a firm makes to deal with such competitive pressures still remain under-explored. The purpose of this paper is to examine the influence of informal competitive pressures in driving export propensity of formal firms.
Design/methodology/approach
The paper is based on a standard error logistic model, and the model takes into account the contingent relationships along with the primary relationship. The authors draw the sample of 9,812 manufacturing firms spanning across the Indian sub-continent from the World Bank enterprise survey conducted in the year 2014.
Findings
The empirical results indicated that the level of competition from informal firms is positively associated with the propensity to export. The primary relationship is also affected by various contingent factors such as regulatory obstacles, bribery and new product development.
Research limitations/implications
Although the World Bank enterprise survey data provide a broad coverage, the study warranted few proxy measures in order to operationalize formal competition as it was not captured directly in the concerned data set.
Practical implications
The analysis demonstrates that informal competition has direct effect on the firm’s propensity to export. The findings indicate that export is an attractive action alternative for firms facing informal completion in an emerging economy. The results further indicate that this effect strengthens as institutional factors such as regulatory obstacles and bribery increase.
Social implications
The paper is an attempt to alter the prevailing negative view on informality. The findings indicate that informal competition spurs competitiveness in the formal sector indicating its positive role in the economic growth of the nation.
Originality/value
The paper takes cue from attention-based view of the firm and the institutional escapism logic to affirm the role of informal competition and various contingent institutional and strategic factors in driving export propensity.
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Maruti K. Rendale, S.N. Mathad and Vijaya Puri
The present communication aims to investigate the influence of cobalt substitution on the structural, mechanical and elastic properties of nickel–zinc ferrite thick films…
Abstract
Purpose
The present communication aims to investigate the influence of cobalt substitution on the structural, mechanical and elastic properties of nickel–zinc ferrite thick films. The changes observed in the crystallite size (D), lattice constant (a), texture coefficient [TC(hkl)] and mechanical and elastic properties of the thick films due to cobalt substitution have been reported systematically.
Design/methodology/approach
Ni–Zn ferrites with the stoichiometric formula Ni0.7−xCoxZn0.3Fe2O4 (where, x = 0, 0.04, 0.08, 0.12, 0.16 and 0.20) were synthesized via solution combustion technique using sucrose as the fuel and poly-vinyl-alcohol as the matrix material. The thick films of the ferrites were fabricated on alumina substrates by the screen printing method. The thickness of the films was 25 μm, as measured by the gravimetric method. The thick films were subjected to X-ray diffraction and Fourier transform infrared spectroscopy.
Findings
The detailed study of variation of lattice parameter (a), sintering density, micro-strain and elastic properties with cobalt (Co+2) substituted was carried out. The remarkable increase in lattice parameter (from 8.369 A° to 8.3825 A°), bulk density and average grain size (69-119 nm) with the cobalt content was due to larger ionic radius of Co2+ compared to Ni2+. Texture analysis [TC(hkl)] reveals all thick films have adequate grain growth in the (311) plane direction. The main absorption bands of spinel ferrite have appeared through infrared absorption spectra recorded in the range of 300-700 cm−1.
Originality/value
The variation in stiffness constants (for isotropic material, C11 = C12), longitudinal elastic wave (Vl), transverse elastic wave (Vt), mean elastic velocity (VMean), rigidity modulus (G), Poisson’s ratio(s) and Young’s modulus (E) with cobalt (Co+2) composition has been interpreted in terms of binding forces found.
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Michal Jan Smolnicki, Michal Ptak and Grzegorz Lesiuk
The combined numerical-experimental approach has been presented. The purpose of this paper is to determine the critical rupture load of the notched components based on the…
Abstract
Purpose
The combined numerical-experimental approach has been presented. The purpose of this paper is to determine the critical rupture load of the notched components based on the cohesive zone modeling (CZM).
Design/methodology/approach
The 42CrMo4 steel (in normalized state) state has been tested and modeled using an eXtended finite element method (xFEM) philosophy with the CZM approach. In order to validate the numerically obtained critical load forces the experimental verification was performed.
Findings
The critical loads were determined for various notch configurations. The numerical and experimental values were compared. Based on this, a good agreement between experimental and numerical data is achieved. The relative error does not exceed 7 percent.
Practical implications
The presented procedure and approach is effective and simple for engineering applications. It is worth to underline that the obtained critical load values for notched components require only the static tensile test results and implementation of the presented route in numerical FEM, xFEM environment.
Originality/value
The presented methodology is actual and still developed. The scientific and engineering value of the presented numerical procedure is high.
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Deepak Jadhav and T.V. Ramanathan
An investor is expected to analyze the market risk while investing in equity stocks. This is because the investor has to choose a portfolio which maximizes the return with…
Abstract
Purpose
An investor is expected to analyze the market risk while investing in equity stocks. This is because the investor has to choose a portfolio which maximizes the return with a minimum risk. The mean-variance approach by Markowitz (1952) is a dominant method of portfolio optimization, which uses variance as a risk measure. The purpose of this paper is to replace this risk measure with modified expected shortfall, defined by Jadhav et al. (2013).
Design/methodology/approach
Modified expected shortfall introduced by Jadhav et al. (2013) is found to be a coherent risk measure under univariate and multivariate elliptical distributions. This paper presents an approach of portfolio optimization based on mean-modified expected shortfall for the elliptical family of distributions.
Findings
It is proved that the modified expected shortfall of a portfolio can be represented in the form of expected return and standard deviation of the portfolio return and modified expected shortfall of standard elliptical distribution. The authors also establish that the optimum portfolio through mean-modified expected shortfall approach exists and is located within the efficient frontier of the mean-variance portfolio. The results have been empirically illustrated using returns from stocks listed in National Stock Exchange of India, Shanghai Stock Exchange of China, London Stock Exchange of the UK and New York Stock Exchange of the USA for the period February 2005-June 2018. The results are found to be consistent across all the four stock markets.
Originality/value
The mean-modified expected shortfall portfolio approach presented in this paper is new and is a natural extension of the Markowitz’s mean-variance and mean-expected shortfall portfolio optimization discussed by Deng et al. (2009).
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Mayur Trivedi, Minjan Patel, Divya Nair H and Bharati Sharma
As the investment in social and health protection remained poor in India, the most vulnerable citizens lack access to existing health related government initiatives with…
Abstract
Purpose
As the investment in social and health protection remained poor in India, the most vulnerable citizens lack access to existing health related government initiatives with transformational benefits due mostly to the lack of “accurate information”. The purpose of this paper is to explore and demonstrate the impact of participation of the community through a structured intervention that promotes awareness, enables the community to ensure entitlements, and enhances the utilization of government initiatives.
Design/methodology/approach
Through a baseline–endline study using a quasi-experimental design, this research provides empirical evidence of such intervention on awareness and utilization of health, nutrition and developmental initiatives. It involved survey of 400 households from the four study locations before and after the interventions. The pre-post estimation in the “proportion of respondents who were fully aware” was analyzed to measure changes in knowledge. Mc-Nemar test was applied to measure the statistical significance of these changes.
Findings
The results indicate that the intervention of “empowerment centers” has increased knowledge and utilization of the various government schemes, services and facilities that are routine and offer benefits all household members, in general, and women as well as children, in particular. The intervention was found to be successful in improving the local governance systems; empowering communities, linking communities and local level government systems across all sectors, as well as bringing in inter-sectoral linkages across governments systems.
Research limitations/implications
Although there have been many interventions of community participation for reducing inequities across the globe, there is a dearth of documentation and evidence generation. More efforts are required to evaluate such interventions, identify which interventions work and how they can be adapted to different contexts. This also requires exploration of the social processes and contextual realities underlying these interventions.
Originality/value
To the best knowledge of the authors, this research is one-of-its-kind that assessed an intervention targeting cross-cutting schemes and services, beyond just health interventions. The evidence points to the success of grassroots level inter-sectoral community actions, in the form of empowerment centers, to improve awareness and utilization of government interventions through participatory governance, and points to the expanding scope of learning and adapting such interventions to different contexts and scopes.
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Shantanu Sharma, Sucheta Rawat, Faiyaz Akhtar, Rajesh Kumar Singh and Sunil Mehra
The authors intend to assess the village health sanitation and nutrition committees (VHSNC) on six parameters, including their formation, composition, meeting frequencies…
Abstract
Purpose
The authors intend to assess the village health sanitation and nutrition committees (VHSNC) on six parameters, including their formation, composition, meeting frequencies, activities, supervisory mechanisms and funds receipt and expenditures across nine districts of the three states of India.
Design/methodology/approach
The cross-sectional study, conducted in the states of Uttar Pradesh (five districts), Odisha (two districts) and Rajasthan (two districts), used a quantitative research design. The community health workers of 140 VHSNCs were interviewed using a semi-structured questionnaire. The details about the funds' receipt and expenditures were verified from the VHSNC records (cashbook). Additionally, the authors asked about the role of health workers in the VHSNC meetings, and the issues and challenges faced.
Findings
The average number of members in VHSNCs varied from 10 in Odisha to 15 in Rajasthan. Activities were regularly organized in Rajasthan and Odisha (one per month) compared to Uttar Pradesh (one every alternate month). Most commonly, health promotion activities, cleanliness drives, community monitoring and facilitation of service providers were done by VHSNCs. Funds were received regularly in Odisha compared to Rajasthan and Uttar Pradesh. Funds were received late and less compared to the demands or needs of VHSNCs.
Research limitations/implications
This comprehensive analysis of VHSNCs' functioning in the selected study areas sheds light on the gaps in many components, including the untimely and inadequate receipt of funds, poor documentation of expenditures and involvement of VHSNC heads and inadequate supportive supervision.
Originality/value
VHSNCs assessment has been done for improving community health governance.
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The existence of the regional Kuznets curve, i.e. an inverted U-shaped relationship between regional disparity and economic development is widely debated and discussed…
Abstract
Purpose
The existence of the regional Kuznets curve, i.e. an inverted U-shaped relationship between regional disparity and economic development is widely debated and discussed. The bell-shaped curve of the spatial growth process where during the initial phase inequality increases and then reduces is theoretically supported by Myrdal (1957), Hirschman (1958), and Williamson (1965). It becomes important to understand regional Kuznets curve globally. Understanding the relationship between regional disparity and economic development becomes essential for public policy for balanced regional growth.
Design/methodology/approach
Regional Kuznets Curve which is an inverted U-shaped relationship between regional disparity and economic development is not a new phenomenon. Theoretical framework by Myrdal (1957), Hirschman (1958), and Williamson (1965) support the an inverted U-shaped relationship. To understand the relationship between regional disparity and economic development, the authors investigate the regional Kuznets curve by using data for 184 countries and 1765 subnational regions. Using parametric, semi-parametric, and non-parametric, it is found that there exists an inverted U-shaped relationship between regional disparity and economic development. The presence of the regional Kuznets curve is observed. As the theoretical framework suggests, regional inequality increases with income initially and decreases after attaining a certain level of income. This study identifies two stages of divergence-convergence where in the first stage, divergence across regions in a country happens with increasing income and in the later stage, convergence across regions in a country occurs with increasing income.
Findings
Using the parametric approach (panel data analysis), semi-parametric and non-parametric approaches, it is found that there exists a regional Kuznets curve. It is found that there exists an inverted-U relationship between regional inequality and per capita GNI. This suggests that the divergence-convergence passes through two stages. In the first stage, divergence across regions in a country happens with increasing income while in the later stage convergence occurs.
Originality/value
This research work has done three important things which fill the research gap that exists in the literature: (1) constructing the Gini coefficient to measure the regional inequality for 184 countries using 1765 subnational regional data; (2) using a parametric approach (panel data analysis) to understand the regional Kuznets phenomenon and (3) using a semi-parametric approach and non-parametric approach to understand the regional Kuznets phenomenon.
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