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1 – 10 of 47Sohail R. Reddy, Matthias K. Scharrer, Franz Pichler, Daniel Watzenig and George S. Dulikravich
This paper aims to solve the parameter identification problem to estimate the parameters in electrochemical models of the lithium-ion battery.
Abstract
Purpose
This paper aims to solve the parameter identification problem to estimate the parameters in electrochemical models of the lithium-ion battery.
Design/methodology/approach
The parameter estimation framework is applied to the Doyle-Fuller-Newman (DFN) model containing a total of 44 parameters. The DFN model is fit to experimental data obtained through the cycling of Li-ion cells. The parameter estimation is performed by minimizing the least-squares difference between the experimentally measured and numerically computed voltage curves. The minimization is performed using a state-of-the-art hybrid minimization algorithm.
Findings
The DFN model parameter estimation is performed within 14 h, which is a significant improvement over previous works. The mean absolute error for the converged parameters is less than 7 mV.
Originality/value
To the best of the authors’ knowledge, application of a hybrid optimization framework is new in the field of electrical modelling of lithium-ion cells. This approach saves much time in parameterization of models with a high number of parameters while achieving a high-quality fit.
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Naeem Ullah, Sohail Nadeem, Luthais McCash, Anber Saleem and Alibek Issakhov
This paper aims to focus on the natural convective flow analysis of micropolar nanofluid fluid in a rectangular vertical container. A heated source is placed in the lower wall to…
Abstract
Purpose
This paper aims to focus on the natural convective flow analysis of micropolar nanofluid fluid in a rectangular vertical container. A heated source is placed in the lower wall to generate the internal flow. In further assumptions, the left/right wall are kept cool, while the upper and lower remaining portions are insulated. Free convection prevails in the regime because of thermal difference in-between the lower warmer and upper colder region.
Design/methodology/approach
The physical setup owns mathematical framework in-terms of non-linear partial differential equations. For the solution purpose of the differential system, finite volume method is adopted. The interesting features of the flow along with thermal transportation involve both translational and rotational movement of fluid particles.
Findings
Performing the simulations towards flow controlling variables the outputs are put together in contour maps and line graphs. It is indicated that the variations in flow profile mass concentration and temperature field augments at higher Rayleigh parameter because of stronger buoyancy effects. Higher viscosity coefficient implies decrease in flow and thermal transportation. Further, the average heat transfer rate also grows by increasing both the Rayleigh parameter and heated source length.
Originality/value
To the best of the authors’ knowledge, no such study has been addressed yet. Further, the results are validated by comparing with previously published work.
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Muhammad Ijaz Khan, Sohail Ahmad Khan, Tasawar Hayat, Muhammad Faisal Javed and Ahmed Alsaedi
This study aims to examine the flow characteristics of Ree–Eyring fluid between two rotating disks. The characteristics of heat transfer are discussed in presence of viscous…
Abstract
Purpose
This study aims to examine the flow characteristics of Ree–Eyring fluid between two rotating disks. The characteristics of heat transfer are discussed in presence of viscous dissipation, heat source/sink and nonlinear radiative heat flux.
Design/methodology/approach
Nonlinear flow expressions lead to ordinary ones through adequate similarity transformations. The ordinary differential system has been tackled through optimal homotopic method. The impact of different flow variables on the velocity field, entropy generation rate and temperature fields is graphically discussed. The surface drag force and heat transfer rate are numerically examined via various pertinent parameters.
Findings
By minimization of values of stretching parameter and Brinkman number, the entropy generation rate can be controlled. The entropy generation rate enhances for higher values of magnetic parameter, while the Bejan number is decreased via magnetic parameter.
Originality/value
No such work is yet published in the literature.
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Muhammad Ijaz Khan, Sohail Ahmad Khan, Tasawar Hayat, Muhammad Faisal Javed and Muhammad Waqas
This paper aims to address the flow features of Ree–Eyring fluid between two rotating disks subject to the magnetic field. Heat transfer features are discussed through viscous…
Abstract
Purpose
This paper aims to address the flow features of Ree–Eyring fluid between two rotating disks subject to the magnetic field. Heat transfer features are discussed through viscous dissipation and nonlinear thermal radiation. Impact of thermophoresis and Brownian movement are elaborated. Physical characteristics of entropy generation optimization in nanofluid with homogeneous and heterogeneous chemical reaction are discussed.
Design/methodology/approach
The nonlinear system leads to ordinary one through the implementation of adequate transformation and then tackled analytically for a convergent series solution by homotopy analysis method.
Findings
The prime objective of the present research has been given to investigate entropy generation in Ree–Eyring fluid flow between two rotating disks subjected to the magnetic field. Vital features, namely, Brownian motion and thermophoresis have been addressed. Total entropy rate is computed using the second law of thermodynamics.
Originality/value
No such work yet exists in the literature.
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P. Sudarsana Reddy and P. Sreedevi
Steady-state mixed convection boundary layer flow, heat and mass transfer characteristics of Buongiorno's model nanofluid over an inclined porous vertical plate with thermal…
Abstract
Purpose
Steady-state mixed convection boundary layer flow, heat and mass transfer characteristics of Buongiorno's model nanofluid over an inclined porous vertical plate with thermal radiation and chemical reaction are presented in this analysis.
Design/methodology/approach
The governing nonlinear partial differential equations represent the flow model that can be converted into system of nonlinear ordinary differential equations using the similarity variables and are solved numerically using finite element method.
Findings
The rates of nondimensional temperature and concentration are both decelerate with the higher values of thermophoresis parameter (Nt).
Originality/value
The work carried out in this paper is original.
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The purpose of this paper is to examine the underpricing of initial public offers (IPOs), which were announced by Indian firms for the period 2007 through 2009. It is motivated by…
Abstract
Purpose
The purpose of this paper is to examine the underpricing of initial public offers (IPOs), which were announced by Indian firms for the period 2007 through 2009. It is motivated by the fact that a well-developed capital market is a function of economic growth and a reflection of the financial system. Thus, this study investigates aftermarket pricing performance of IPOs during the recent global financial crisis.
Design/methodology/approach
This paper studies the underpricing of 133 IPOs in three groups, namely, house-full collections, short-run and long-run periods. To do so, it uses event study method to observe underpricing, which is examined in various window periods. Further, industry- and year-wise offers are analyzed and interpreted. Accordingly, hypotheses are being developed and tested through a static “analysis of variance”.
Findings
The study explores that post-listing IPOs assure positive returns in the short run, but they tend to plunge and become negative in the long run. In particular, highest returns have been observed in the first week of post-listing.
Research limitations/implications
Limitations include, the study does not compute market-adjusted returns to find abnormal performance of stocks, and does not apply regression statistic to examine the factors that affect underpricing.
Practical implications
Eventually, conclusions are drawn from India–international results, and thus it would add some new insights on investor perspectives (e.g. price signalling) to the existing IPOs literature, especially from Asian markets context.
Originality/value
This paper is an original research that examines the underpricing of Indian IPOs during the recent financial crisis, particularly in three groups: house-full collections, short-run and long-run periods.
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Muhammad Sohail and Sana Tariq
Thermal and species transport of magneto hydrodynamic Casson liquid over a stretched surface is investigated theoretically in this examination for the three-dimensional boundary…
Abstract
Purpose
Thermal and species transport of magneto hydrodynamic Casson liquid over a stretched surface is investigated theoretically in this examination for the three-dimensional boundary layer flow of a yield exhibiting material. The phenomenon of heat and species relocation is based upon modified Fourier and Fick’s laws that involves the relaxation times for the transportation of heat and mass. Conservation laws are modeled under boundary layer analysis in the Cartesian coordinates system. The purpose of this paper is to find the influence of different emerging parameters on fluid velocity, temperature and transport of species.
Design/methodology/approach
Reconstructed nonlinear boundary layer ordinary differential equations are analyzed through eigenvalues and eigenvectors. Due to the complexity and non-existence of the exact solution of the transformed equations, a convergent series solution by the homotopy algorithm is also derived. The reliability of the applied scheme is presented by comparing the obtained results with the previous findings.
Findings
Physical quantities of interest are displayed through graphs and tables and discussed for sundry variables. It is discerned that higher magnetic influence slows down fluid motion, whereas concentration and temperature profiles upsurge. Reliability of the recommended scheme is monitored by comparing the obtained results for the dimensionless stress as a limiting case of previous findings and an excellent agreement is observed. Higher values of Schmidt number reduce the concentration profile, whereas mounting the values of Prandtl number reduces the dimensionless temperature field. Moreover, heat and species transfer rates increase by mounting the values of thermal and concentration relaxation times.
Originality/value
The phenomenon of heat and species relocation is based upon modified Fourier and Fick’s laws which involves the relaxation times for the transportation of heat and mass. Conservation laws are modeled under boundary layer analysis in the Cartesian coordinates system.
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Dhanavanth Reddy Maditati, Sebastian Kummer, Ziaul Haque Munim and Hans-Joachim Schramm
According to the logistics performance index, emerging countries such as India are lagging behind developed countries such as Germany, Austria and Switzerland (DACH region). The…
Abstract
Purpose
According to the logistics performance index, emerging countries such as India are lagging behind developed countries such as Germany, Austria and Switzerland (DACH region). The purpose of this study is to compare and understand the differences in logistics outsourcing outlook in the two regions by considering both manufacturing firms (M-firms) and logistics service providers’ (LSPs) perspectives.
Design/methodology/approach
A survey targeting both LSPs and M-firms in DACH and India is conducted. A total of 96 responses were analyzed by using the chi-square test to investigate the differences and alignments in outsourcing motivation, relationship and governance between firms within and across regions.
Findings
M-firms in India bear strategic motivations behind outsourcing and those in DACH incline towards costs. LSPs in both regions align with the motivations of M-firms. M-firms in India rely more on LSPs by transferring the ownership of outsourced tasks, as compared to DACH. Both M-firms and LSPs in DACH claim a high level of ownership. However, firms in DACH and India do not differ significantly in terms of outsourcing engagements they seek.
Research limitations/implications
The findings may only be generalized to large firms in India and DACH.
Practical implications
The findings of this study help managers enhance their understanding of the differences between M-firms and LSPs, and also across countries. LSPs in DACH, if they wish to operate successfully in India, will have to adapt to the M-firms strategic motivations and offer higher dependency.
Originality/value
This study is novel, as it investigates differences between India and DACH countries while also including both manufacturers’ and logistics service providers’ perspectives.
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Ziaul Haque Munim, Dhanavanth Reddy Maditati, Sebastian Kummer and Hans-Joachim Schramm
This study aims to explore the gaps concerning the organizational operant resources (OORs) of logistics service providers (LSPs) expected in outsourcing relationships. The study…
Abstract
Purpose
This study aims to explore the gaps concerning the organizational operant resources (OORs) of logistics service providers (LSPs) expected in outsourcing relationships. The study considers the views of both manufacturing firms (M-firms) and LSPs in India and DACH region (Germany, Austria and Switzerland) seeking gaps within and across regions.
Design/methodology/approach
This research employed a survey targeting executives from large M-firms and LSPs in both India and DACH. The perceptions about the importance and improvement expectations of 17 OORs are analyzed. A modified version of importance-improvement analysis (A-B), a novel comparative A-B analysis (CABA) method, has been proposed to identify the importance and improvement gaps in OORs between M-firms and LSPs within and across India and the DACH region.
Findings
There are more gaps between M-firms and LSPs in India compared to DACH. Cross-country comparisons reveal that LSPs in India and DACH have similar perceptions concerning the OORs, but M-firms in India have significantly higher improvement expectations than those in DACH.
Research limitations/implications
This study proposes an analytical approach that enables managers to identify improvement areas and better align with their outsourcing relationship partners. It also highlights aspects that need to be considered while entering emerging markets such as India.
Originality/value
The analysis approach using CABA is novel. Also, among the cross-country studies, this is the first to compare outsourcing relationships in India with the DACH region while involving both users' and service providers' perspectives.
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Samra Chaudary, Sohail Zafar and Thomas Li-Ping Tang
Following behavioral finance and monetary wisdom, the authors theorize: Decision-makers (investors) adopt deep-rooted personal values (the love-of-money attitudes/avaricious…
Abstract
Purpose
Following behavioral finance and monetary wisdom, the authors theorize: Decision-makers (investors) adopt deep-rooted personal values (the love-of-money attitudes/avaricious financial aspirations) as a lens to frame critical concerns (short-term and long-term investment decisions) in the immediate-proximal (current income) and distal-omnibus (future inheritance) contexts to maximize expected utility and ultimate serenity across context, people and time.
Design/methodology/approach
The authors collected data from 277 active equity traders (professional money managers and individual investors) in Pakistan’s two most robust investment hubs—Karachi and Lahore. The authors measured their love-of-money attitude (avaricious monetary aspirations), short-term and long-term investment decisions and demographic variables and collected data during Pakistan's bear markets (Pakistan Stock Exchange, PSX-100).
Findings
Investors’ love of money relates to short-term and long-term decisions. However, these relationships are significant for money managers but non-significant for individual investors. Further, investors’ current income moderates this relationship for short-term investment decisions but not long-term decisions. The intensity of the aspirations-to-short-term investment relationship is much higher for investors with low-income levels than those with average and high-income levels. Future inheritance moderates the relationships between aspirations and short-term and long-term decisions. Regardless of their love-of-money orientations, investors with future inheritance have higher magnitudes of short-term and long-term investments than those without future inheritance. The intensity of the aspirations-to-investments relationship is more potent for investors without future inheritance than those with inheritance. Investors with low avaricious monetary aspirations and without inheritance expectations show the lowest short-term and long-term investment decisions. Investors' current income and future inheritance moderate the relationships between their love of money attitude and short-term and long-term decisions differently in Pakistan's bear markets.
Practical implications
The authors help investors make financial decisions and help financial institutions, asset management companies, brokerage houses and investment banks identify marketing strategies and investor segmentation and provide individualized services.
Originality/value
Professional money managers have a stronger short-term orientation than individual investors. Lack of wealth (current income and future inheritance) motivates greedy investors to take more risks and become more vulnerable than non-greedy ones—investors’ financial resources and wealth matter. The Matthew Effect in investment decisions exists in Pakistan’s emerging economy.
Details
Keywords
- Behavioural finance/economics/prospect theory/risk-taking/aversion
- Planned behaviour/TPB
- Values
- Love of money/money/greed/power/achievement/obsession/budget
- Current/income/future/inheritance/time/gender
- Short-term/Long-term/Decision-making
- Conservation/resource/wealth/possession/stress
- Bull/Bear/Market
- Pakistan Stock Exchange (PSX-100)