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Article
Publication date: 2 August 2011

Franciszek Balik

The purpose of this paper is to present a new method of optimization of electronic integrated circuits (IC) with imbedded passive modules (PM). The reported method…

Abstract

Purpose

The purpose of this paper is to present a new method of optimization of electronic integrated circuits (IC) with imbedded passive modules (PM). The reported method constitutes an attempt to streamline the optimization process in the AC electrical model stage of the RF Microsystems design.

Design/methodology/approach

In this method, the PM are described in symbolic form while the IC blocks remain described numerically. Whole PM can be represented as some sequence of expressions containing crucial model parameters, nominal and parasitic, which are first precompiled and next, merged automatically with the main program.

Findings

The input data can be updated online according to the user's desiderata. Further, the system offers the possibility to optimize PM in diverse circumstances as well as using different technologies, and including parasitic effects.

Originality/value

Usage of the semi‐symbolic method for IC with embedded PM optimization based on large‐change sensitivity AC analysis method, which appears to be a very efficient and flexible approach to solving such problems.

Details

Microelectronics International, vol. 28 no. 3
Type: Research Article
ISSN: 1356-5362

Keywords

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Article
Publication date: 1 March 1991

D.C. Whalley

There is continued concern over the ability of SMD solder joints to survive in the harsh operating environments endured, for example, by automotive and aerospace products…

Abstract

There is continued concern over the ability of SMD solder joints to survive in the harsh operating environments endured, for example, by automotive and aerospace products. This paper will review the techniques available for analysing solder joint fatigue behaviour and then describe a software tool designed to allow estimation and comparison of the thermal fatigue life of solder joints exposed to a complex operating profile. The modelling technique takes account of the large changes with temperature of the solder alloys stress/strain‐rate behaviour and also the complex geometry of the component/solder/PCB assembly, whilst avoiding the very high cost of non‐linear finite element analysis. This is achieved by first performing a linear stress analysis of the assembly in order to determine its compliance, and then using this compliance estimate in the solution of a non‐linear differential equation describing the relationship between temperature, stress and strain‐rate in the joint. The technique has been implemented as a software package known as ECLIPS—Electronic Connection Life Prediction System. This software package will run on a workstation or PC and has been shown to give results very close to those from non‐linear finite element analysis, but at approximately 1/20th of the cost.

Details

Soldering & Surface Mount Technology, vol. 3 no. 3
Type: Research Article
ISSN: 0954-0911

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Article
Publication date: 17 July 2020

Sonalika Mishra, Suchismita Patel, Ramesh Chandra Prusty and Sidhartha Panda

This paper aims to implement a maiden methodology for load frequency control of an AC multi micro-grid (MG) by using hybrid fractional order fuzzy PID (FOFPID) controller…

Abstract

Purpose

This paper aims to implement a maiden methodology for load frequency control of an AC multi micro-grid (MG) by using hybrid fractional order fuzzy PID (FOFPID) controller and linear quadratic Gaussian (LQG).

Design/methodology/approach

The multi MG system considered is consisting of photovoltaic, wind turbine and a synchronous generator. Different energy storage devices i.e. battery energy storage system and flywheel energy storage system are also integrated to the system. The renewable energy sources suffer from uncertainty and fluctuation from their nominal values, which results in fluctuation of system frequency. Inspired by this difficulty in MG control, this research paper proposes a hybridized FOFPID and LQG controller under random and stochastic environments. Again to confer viability of proposed controller its performances are compared with PID, fuzzy PID and fuzzy PID-LQG controllers. A comparative study among all implemented techniques i.e. proposed multi-verse optimization (MVO) algorithm, particle swarm optimization and genetic algorithm has been done to justify the supremacy of MVO algorithm. To check the robustness of the controller sensitivity analysis is done.

Findings

The merged concept of fractional calculus and state feedback theory is found to be efficient. The designed controller is found to be capable of rejecting the effect of disturbances present in the system.

Originality/value

From the study, the authors observed that the proposed hybrid FOPID and LQG controller is robust hence, there is no need to reset the controller parameters with a large change in network parameters.

Details

World Journal of Engineering, vol. 17 no. 5
Type: Research Article
ISSN: 1708-5284

Keywords

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Article
Publication date: 9 April 2018

Amita Majumder, Ranjan Ray and Sattwik Santra

The purpose of this study is to examine the sensitivity of regional and world poverty rates to the purchasing power parities (PPP) used in the calculations. The PPPs are…

Abstract

Purpose

The purpose of this study is to examine the sensitivity of regional and world poverty rates to the purchasing power parities (PPP) used in the calculations. The PPPs are required to convert the “international poverty line” typically denominated in US dollar to its local currency equivalent in the various countries. While recent studies on world poverty differ with respect to the specification of the international poverty line (IPL), they universally use the PPP available from the international comparison program (ICP). This study provides a departure and calculates PPPs using the Gini–Elteto–Koves–Szulc (GEKS) price index and country product dummy (CPD) model as alternatives to the ICP PPPs. The GEKS and CPD PPPs are compared with the ICP PPPs. The paper then compares the global and regional poverty rates based on the three sets of PPPs and presents evidence of significant revision to the poverty rates if we depart from the use of the ICP PPPs. The study tests for the presence of serial correlation between price movements in different countries and investigates its impact on the PPPs. The methodological contribution of this paper is to establish the close nexus between price indices and poverty rates via the PPPs used in obtaining the local currency unit (LCU) denominated IPL.

Design/methodology/approach

The PPP calculations in this paper relate to the ICP round, 2011. Along with the ICP PPPs from published reports (with India as the numeraire country), we report the following indices, namely, the GEKS, weighted CPD and its two spatially correlated generalisations. The ICP PPPs are used as benchmark. The ICP group in the World Bank made the price and expenditure information for 2011 available. Corresponding poverty rates are calculated at the country, regional and global levels.

Findings

The empirical evidence points to the fact that while at the country level the alternative calculations have high impact on the implied poverty rates, at the regional and global level the rates are reasonably quite robust.

Research limitations/implications

Three points are worth noting, namely, as opposed to the PPP for “Individual consumption expenditure by households” (ICEH), which is the PPP used for international poverty monitoring by the World Bank and others, we have used the ICP PPPs for “Actual individual consumption” (AIC); although ICP uses the GEKS procedure above the BH level, we independently calculated these PPPs using the price information provided, and the base country has been moved from the USA to India.

Practical implications

One can come up with independently estimated PPPs that do not require the elaborate and expensive procedure set up by the ICP and can arrive at robust poverty rates at the regional and global level.

Social implications

The change in base has been made as India shares many of the features of a developing country including high poverty rates, but at the same time provides a market and an economy size that places it in the top tier of nations. In addition, poverty comparisons amongst developing countries can be made using these PPPs directly, without reference to the USA. The poverty calculations are based on the PovcalNet program.

Originality/value

There is no clear answer to the question “how robust are the global poverty numbers to departures from the ICP PPPs?” in the literature nor is there any evidence on the robustness of the ICP PPPs themselves to changes in the ICP methodology. Given that the ICP uses the Gini–Elteto–Koves–Szulc (GEKS) multilateral price index in aggregation of ICP PPP basic heading data, in an attempt to partially answer this question this study examines the sensitivity of measures of relative prices (and poverty) to using CPD (and various spatial versions) and GEKS methods, using price data provided by the World Bank. It also verifies how these PPPs track the published 2011 ICP PPPs, which are used as benchmark.

Details

Indian Growth and Development Review, vol. 11 no. 1
Type: Research Article
ISSN: 1753-8254

Keywords

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Article
Publication date: 17 September 2018

Md. Abdul Moktadir, Syed Mithun Ali, Sachin Kumar Mangla, Tasnim Ahmed Sharmy, Sunil Luthra, Nishikant Mishra and Jose Arturo Garza-Reyes

Managing risks is becoming a highly focused activity in the health service sector. In particular, due to the complex nature of processes in the pharmaceutical industry…

Abstract

Purpose

Managing risks is becoming a highly focused activity in the health service sector. In particular, due to the complex nature of processes in the pharmaceutical industry, several risks have been associated to its supply chains. The purpose of this paper is to identify and analyze the risks occurring in the supply chains of the pharmaceutical industry and propose a decision model, based on the Analytical Hierarchy Process (AHP) method, for evaluating risks in pharmaceutical supply chains (PSCs).

Design/methodology/approach

The proposed model was developed based on the Delphi method and AHP techniques. The Delphi method helped to select the relevant risks associated to PSCs. A total of 16 sub risks within four main risks were identified through an extensive review of the literature and by conducting a further investigation with experts from five pharmaceutical companies in Bangladesh. AHP contributed to the analysis of the risks and determination of their priorities.

Findings

The results of the study indicated that supply-related risks such as fluctuation in imports arrival, lack of information sharing, key supplier failure and non-availability of materials should be prioritized over operational, financial and demand-related risks.

Originality/value

This work is one of the initial contributions in the literature that focused on identifying and evaluating PSC risks in the context of Bangladesh. This research work can assist practitioners and industrial managers in the pharmaceutical industry in taking proactive action to minimize its supply chain risks. To the end, the authors performed a sensitivity analysis test, which gives an understanding of the stability of ranking of risks.

Details

Industrial Management & Data Systems, vol. 118 no. 7
Type: Research Article
ISSN: 0263-5577

Keywords

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Article
Publication date: 15 January 2018

Lordina Amoah and Meshach Jesse Aziakpono

The purpose of this paper is to reexamine the speed and magnitude of exchange rate pass-through (ERPT) to consumer prices in Ghana.

Abstract

Purpose

The purpose of this paper is to reexamine the speed and magnitude of exchange rate pass-through (ERPT) to consumer prices in Ghana.

Design/methodology/approach

The Johansen Maximum Likelihood approach is employed in the estimation of different models of symmetric and asymmetric ERPT. Specifically asymmetric ERPT models with respect to the direction and size of exchange rate changes are estimated.

Findings

Results reveal that even though a depreciation in the nominal effective exchange rate will lead to an increase of consumer prices in the long-run, it is not statistically significant. Evidence also suggests a significant asymmetry with respect to direction and size of exchange rate changes. This indicates that the right ERPT model is an asymmetric model. Specifically ERPT is found to be incomplete but relatively higher in periods of depreciation than in periods of appreciation; that is 53 percent against 3 percent. ERPT is also higher during episodes of large changes (about 51 percent).

Research limitations/implications

It would have been interesting to analyze the impact on consumer prices through changes in import prices. That approach was not adopted due to lack of consistent data on import prices in Ghana.

Practical implications

It is imperative that the monetary authorities critically monitor exchange rate movements in order to be able to take swift policy action so as to counteract any inflationary pressures from the external sector. In particular, much attention should be paid to events and arrangements that could result in large depreciation of the exchange rate.

Originality/value

While previous studies have assumed a symmetric ERPT model for Ghana, this paper is unique in that it investigates the most appropriate model for examining ERPT in Ghana whether symmetric or an asymmetric.

Details

International Journal of Emerging Markets, vol. 13 no. 1
Type: Research Article
ISSN: 1746-8809

Keywords

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Article
Publication date: 28 April 2020

Syed Alamdar Ali Shah, Raditya Sukmana and Bayu Arie Fianto

The purpose of this research is to propose a framework for research on Macaulay duration and establish future research directions.

Abstract

Purpose

The purpose of this research is to propose a framework for research on Macaulay duration and establish future research directions.

Design/methodology/approach

Thematic, bibliometric and content analyses have been used to review 168 research papers published between 1938 and 2019 taken from ISI Web of Science and Scopus contributed by leading authors, journals and regulatory bodies.

Findings

Identification and integration of themes of duration theory, duration model development and duration model implementation leading to unattended research gaps, and framework for research on Macaulay duration.

Research limitations/implications

The study is based on an extensive review of the literature to extract important themes, research gaps and frameworks. It does not empirically investigate significance of Macaulay duration and various sectors.

Practical implications

This research has several aspects that are helpful for practitioners. Macaulay duration has been the subject of empirical research only without any guiding framework. This research provides a platform to initiate profound researches in various areas of finance. Various proposed models are required to be tested under holistic approach in conventional and emerging fields, especially in Islamic settings.

Originality/value

This research highlights, research themes leading to framework, research gaps and factors that are crucial in developing, extending and testing duration models leading to enhancement of theoretical base of Macaulay duration.

Details

Journal of Economic Studies, vol. 48 no. 1
Type: Research Article
ISSN: 0144-3585

Keywords

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Article
Publication date: 16 July 2021

Roghayeh Chenary, Akram Karimi-Shahanjarini, Saeid Bashirian, Ghodratollah Roshanaei, Ali Akbar Fazaeli and Mohsen Jalilian

The high prevalence of hypertension is a significant concern worldwide. A decrease in salt intake is a well-known strategy to control hypertension and reduce the risk of…

Abstract

Purpose

The high prevalence of hypertension is a significant concern worldwide. A decrease in salt intake is a well-known strategy to control hypertension and reduce the risk of cardiovascular diseases. Little is known about the factors influencing salt intake behaviors in settings such as Iran where consumption of salt is higher than the recommended amount. The purpose of this study was to find out what factors affect three salt intake behaviors among women: adding salt when cooking, adding salt to prepared food at the table and purchasing salty foods.

Design/methodology/approach

A community-wide cross-sectional survey of 516 women was conducted in Ilam, Iran. Participants were recruited using the cluster random sampling method. The survey included behaviors and variables of an expanded theory of planned behavior. The hypothesized relationships were investigated using structural equation modeling.

Findings

Perceived behavioral control (PBC) (p < 0.001) and habit (p = 0.01) appeared to be significant factors of adding salt when cooking. Determinants of adding salt to food at the table were intention (p < 0.001), PBC (p < 0.001), habit (p < 0.001). Also, PBC (p < 0.001), intention (p < 0.001), habit (p < 0.001) were identified as predictors of the purchase of salty foods. The results did not support the moderating role of Hedonic feeling to salt on the relation between intention and behaviors.

Originality/value

This study would be applicable to develop salt reduction interventions. Because altering the hedonic response to food is difficult, the lack of its moderating role could be a promising finding for developing salt reduction interventions.

Details

Nutrition & Food Science , vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0034-6659

Keywords

Abstract

Details

Dynamic Linkages and Volatility Spillover
Type: Book
ISBN: 978-1-78635-554-6

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Article
Publication date: 1 August 2006

Tracey West and Andrew C Worthington

This paper employs a Generalised Autoregressive Conditional Heteroske‐dasticity in Mean (GARCH‐M) model to consider the effect of macroeconomic factors on Australian…

Abstract

This paper employs a Generalised Autoregressive Conditional Heteroske‐dasticity in Mean (GARCH‐M) model to consider the effect of macroeconomic factors on Australian property returns over the period 1985 to 2002. Three direct (office, retail and industrial property) and two indirect (listed property trust and property stock) returns are included in the analysis, along with market returns, short, medium and long‐term interest rates, expected and unexpected inflation, construction activity and industrial employment and production. In general, macroeconomic factors are found to be significant risk factors in Australian commercial property returns. However, the results also indicate that forecast accuracy in these models is higher for direct office, listed property trust and property stock returns and that the persistence of volatility shocks varies across the different markets, with volatility half lives of between five and seven months for direct retail and industrial property, two and three months for direct office property and less than two months with both forms of indirect property investment.

Details

Journal of Financial Management of Property and Construction, vol. 11 no. 2
Type: Research Article
ISSN: 1366-4387

Keywords

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