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1 – 10 of 137Amr M. Wahaballa, Seham Hemdan and Fumitaka Kurauchi
Road pricing is an efficient strategy for managing urban traffic to relieve congestion. The macroscopic fundamental diagram (MFD), which relates the average network density and…
Abstract
Purpose
Road pricing is an efficient strategy for managing urban traffic to relieve congestion. The macroscopic fundamental diagram (MFD), which relates the average network density and flow, is a simple tool for assessing road pricing effects on transportation network performance. However, recent research indicates that it may have complexity (an MFD hysteresis loop), especially for city-scale networks. Although ignoring MFD hysteresis may provide inaccurate results, pricing models that consider this hysteresis are scarce. This paper aims to assess road pricing effects on network performance considering MFD hysteresis characteristics.
Design/methodology/approach
This paper evaluated different pricing strategies spatially and temporally and compared network performance based on MFD shape in the presence of MFD hysteresis loops. These strategies were developed on a multimodal (cars and buses) network using a multi-agent transport simulation (MATSim).
Findings
This study found that pricing some links for a short duration with an optimum charge calculated based on the MFD provides higher travel time savings than the previous relevant studies.
Originality/value
These findings may facilitate assessing road pricing effects on multimodal network performance considering MFD hysteresis.
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Muhammad Saadullah, Zhipeng Zhang and Hao Hu
The expected benefits of newly developed transportation infrastructures are the saving of travel time and further promoted transport economics. There is a need for a methodology…
Abstract
Purpose
The expected benefits of newly developed transportation infrastructures are the saving of travel time and further promoted transport economics. There is a need for a methodology of travel time estimation with acceptable robustness and practicability. Macroscopic fundamental diagram (MFD) represents the overall traffic performance at a network level by linking average flow, speed and density. MFD can be used to estimate network state and to describe various traffic management strategies. This study aims to describe the effect of new infrastructure development on the network performance using the MFD framework.
Design/methodology/approach
The scenarios of Islamabad Road network before and after the infrastructure construction were simulated, in which the floating car data set (FCD) for multiple modes was extracted. MFD has been formed for the whole region and partitioned region, which was divided on the basis of infrastructural changes. Moreover, this study has been extended to calculate travel time for multiple modes using the MFD results and the Bureau of Public Roads (BPR) function at a neighborhood level.
Findings
MFD results for the whole network showed that the speed of traffic improves after the construction of new infrastructure. The travel time estimates using MFD results were dependent on the speed estimates, whereas the estimates obtained using the BPR function were found to be dependent on the traffic volume variation during different intervals of the day. By using the FCD for multiple modes, travel time estimates for multiple modes were obtained. The BPR function method was found valid for estimating travel time of traffic stream only.
Originality/value
This paper innovatively investigates the change in network performance for pre-construction and post-construction scenarios using the MFD framework. In practice, the approach presented can be used by transportation agencies to evaluate the effect of different traffic management strategies and infrastructural changes.
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Suman Kumar Deb, Ruchi Jain, Sridhar Manohar and Sanjiv Marwah
Usage of updated technology is continuously empowering customer relationship management (CRM) to be convenient and user friendly, where customers are kept engaged with knowledge…
Abstract
Purpose
Usage of updated technology is continuously empowering customer relationship management (CRM) to be convenient and user friendly, where customers are kept engaged with knowledge and information. This enables them on decision-making and managing their portfolio, especially in mutual fund investments. To improve toward a positive decision, certain quality related variables needed to be considered. Thus, this study aims to estimate the mediation effect of relationship quality and outcome (RQO) between CRM and investment decision-making in mutual funds (MFD).
Design/methodology/approach
The descriptive study adopted the constructs from existing empirical literatures to conceptualize the model with three higher order constructs with 12 dimensions. Survey method is used, and with a structured questionnaire, a total of 323 mutual fund investors were approached using nonprobability criterion sampling technique, of which 262 relevant responses were considered for estimating the structural model. Smart PLS was used to establish the relationship of the constructs.
Findings
The result emphasizes a significant direct and indirect relationship indicating that investors are more inclined to MFD through technology-enabled CRM and RQO plays a vital role in explaining the direct relationship between CRM and MFD. The results of the study are in-line with the existing literature.
Practical implications
The study highlights that financial institutions must focus not only on technological diffusion but also needs to ensure quality service by providing knowledge and information during every access of transactions by customers, making them independent and confident during investments.
Originality/value
This study indicates how capacity efficiency, which is a part of service productivity, can be managed without affecting the outcome efficiency by incorporating technology in the place of human interaction during relationship acquiring and retaining process.
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Recep M. Gorguluarslan, Umesh N. Gandhi, Yuyang Song and Seung-Kyum Choi
Methods to optimize lattice structure design, such as ground structure optimization, have been shown to be useful when generating efficient design concepts with complex truss-like…
Abstract
Purpose
Methods to optimize lattice structure design, such as ground structure optimization, have been shown to be useful when generating efficient design concepts with complex truss-like cellular structures. Unfortunately, designs suggested by lattice structure optimization methods are often infeasible because the obtained cross-sectional parameter values cannot be fabricated by additive manufacturing (AM) processes, and it is often very difficult to transform a design proposal into one that can be additively designed. This paper aims to propose an improved, two-phase lattice structure optimization framework that considers manufacturing constraints for the AM process.
Design/methodology/approach
The proposed framework uses a conventional ground structure optimization method in the first phase. In the second phase, the results from the ground structure optimization are modified according to the pre-determined manufacturing constraints using a second optimization procedure. To decrease the computational cost of the optimization process, an efficient gradient-based optimization algorithm, namely, the method of feasible directions (MFDs), is integrated into this framework. The developed framework is applied to three different design examples. The efficacy of the framework is compared to that of existing lattice structure optimization methods.
Findings
The proposed optimization framework provided designs more efficiently and with better performance than the existing optimization methods.
Practical implications
The proposed framework can be used effectively for optimizing complex lattice-based structures.
Originality/value
An improved optimization framework that efficiently considers the AM constraints was reported for the design of lattice-based structures.
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D. Murugan and R. Sekar
The effect of magnetic field dependent (MFD) viscosity on the onset of convection in a ferromagnetic fluid layer heated from below saturating rotating porous medium in the…
Abstract
Purpose
The effect of magnetic field dependent (MFD) viscosity on the onset of convection in a ferromagnetic fluid layer heated from below saturating rotating porous medium in the presence of vertical magnetic field is investigated theoretically by using Darcy model. The resulting eigen value problem is solved using the regular perturbation technique. Both stationary and oscillatory instabilities have been obtained. It is found that increase in MFD viscosity and increase in magnetic Rayleigh number is to delay the onset of ferroconvection, while the nonlinearity of fluid magnetization has no influence on the stability of the system.
Design/methodology/approach
The thermal perturbation method is employed for analytical solution. A theory of linear stability analysis and normal mode technique have been carried out to analyze the onset of convection for a fluid layer contained between two impermeable boundaries for which an exact solution is obtained.
Findings
The conditions for the system to stabilize both by stationary and oscillatory modes are studied. Even for the oscillatory system of particular frequency dictated by physical conditions, the critical Rayleigh numbers for oscillatory mode of the system were found to be greater than for the stationary mode. The system gets destabilized for various physical parameters only through stationary mode. Hence, the analysis is restricted to the stationary mode. To the Coriolis force, the Taylor number Ta is calculated to discuss the results. It is found that the system stabilizes through stationary mode for values of and for oscillatory instability is favored for Ta > 104. Therefore the Taylor number Ta leads to stability of the system. For larger rotation, magnetization leads to destabilization of the system. The MFD viscosity is found to stabilize the system.
Originality/value
This research paper is new and original.
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Maryam Naebe, Bruce McGregor, Melanie Dowling and David Tester
The purpose of this paper is to identify the significant factors important for prickle discomfort properties of commercial wool knitwear and to analyse information on variability…
Abstract
Purpose
The purpose of this paper is to identify the significant factors important for prickle discomfort properties of commercial wool knitwear and to analyse information on variability of garments manufactured over two decades, a total of 177 purchased garments were tested.
Design/methodology/approach
The relationship between the attributes of the reversed engineered garments and garment comfort, as assessed by Wool ComfortMeter, was determined.
Findings
The results indicate that: mean fibre diameter had the most significant effect on prickle assessment; the coefficient of variation of fibre diameter interacted with fabric thickness in affecting prickle discomfort; and rib knit structures were pricklier than single jersey structures.
Originality/value
The results provide objective evidence that the consumer surveys reporting dissatisfaction with the prickle discomfort of wool are based on real consumer experiences of prickle discomfort and are not based on “prejudice” against wool garments.
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To investigate the role played by corporate entrepreneurs in the strategic renewal of mature manufacturing companies.
Abstract
Purpose
To investigate the role played by corporate entrepreneurs in the strategic renewal of mature manufacturing companies.
Design/methodology/approach
A case study approach is adopted as a means of identifying links between corporate entrepreneurship and social capital. Data are drawn from a three‐year study which incorporates formal and informal interviews with 15 members of a pseudonymous company management team.
Findings
The study extends understanding of limits between corporate entrepreneurship and social capital in three ways: corporate entrepreneurs (CEs) can exploit “structural holes” for the benefit of the organisation rather than for career advancement; newcomers are more effective than insiders in overcoming the relational inertia caused by lack of external links; the bridging actions of CEs are important for linking internal activities as well as for accessing external knowledge.
Originality/value
The case is used, in combination with earlier contributions to the literature, as a basis for reconceptualizing the process of corporate entrepreneurship.
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The purpose of this paper is to implement an optimization approach for the tilting‐pad journal bearing using the genetic algorithm (GA), and compare the results with the method of…
Abstract
Purpose
The purpose of this paper is to implement an optimization approach for the tilting‐pad journal bearing using the genetic algorithm (GA), and compare the results with the method of feasible design (MFD).
Design/methodology/approach
The optimum design of a five‐pad tilting‐pad bearing is studied for the optimal performance, considering system minimum power loss along with design criteria such as: fluid film thickness, film temperature, and film pressure with respect to design variables consisting of pad axial length to journal diameter ratio, pad arc length, bearing radial clearance, pad offset factor, and pad preload factor.
Findings
The algorithms are repeated until no search direction can be found that will improve objective function without violating the constraints. Thus, the algorithms are performed for complete search to get the best possible solution of the design. The comparison mainly focuses on the empirical solutions. The GA obtained reasonably good results for the objective function and comparable to the MFD.
Originality/value
The availability of the GA is certainly of value because it allows the exploration of many different configurations of design variables and therefore also contributes to the better knowledge of the rotor‐bearing system behavior in general.
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Surya Mahadevan, Jayanthi Thanigan and Srinivasa Reddy
The case is written based on general experience.
Abstract
Research methodology
The case is written based on general experience.
Case overview/synopsis
Zealvita is a challenger brand to NutriMalt in the white malted food drink (MFD) category. It has a product formula that compares favorably on taste and equally on nutrition. However, Zealvita is not able to translate the power product formula to a winning market formula. Drawing on its legacy and strong adoption route, NutriMalt built a dominant 88% market share in the White MFD category. The market rule of “disproportionate market share for the leading brand” applies with inexorable force in MFD. Smarting at the low market share, Zealvita is in search of a marketing strategy to create churn. Rajiv Product Manager of Zealvita believes that consumer sales promotion of a higher order and at a higher frequency than what is normal can tilt the scales. From Zealvita’s perspective is there a strategic advantage in operating consumer promotion? Is it safe to assume that NutriMalt will not retaliate with consumer promotion? Can consumer sales promotion be sustained at planned frequency? What is the logic in a continuous consumer promotion program?
Complexity academic level
This case can be used at the post-graduate level in the Marketing Strategy course or in a course that has a sales promotion management or competition management segment. This case is also appropriate for use in executive education programs.
Supplementary materials
Teaching notes are available for educators only. Please contact your library to gain login details or email support@emeraldinsight.com to request teaching notes.
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Wasiq Ullah, Faisal Khan, Muhammad Umair and Bakhtiar Khan
This paper aims to reviewed analytical methodologies, i.e. lumped parameter magnetic equivalent circuit (LPMEC), magnetic co-energy (MCE), Laplace equations (LE), Maxwell stress…
Abstract
Purpose
This paper aims to reviewed analytical methodologies, i.e. lumped parameter magnetic equivalent circuit (LPMEC), magnetic co-energy (MCE), Laplace equations (LE), Maxwell stress tensor (MST) method and sub-domain modelling for design of segmented PM(SPM) consequent pole flux switching machine (SPMCPFSM). Electric machines, especially flux switching machines (FSMs), are accurately modeled using numerical-based finite element analysis (FEA) tools; however, despite of expensive hardware setup, repeated iterative process, complex stator design and permanent magnet (PM) non-linear behavior increases computational time and complexity.
Design/methodology/approach
This paper reviews various alternate analytical methodologies for electromagnetic performance calculation. In above-mentioned analytical methodologies, no-load phase flux linkage is performed using LPMEC, magnetic co-energy for cogging torque, LE for magnetic flux density (MFD) components, i.e. radial and tangential and MST for instantaneous torque. Sub-domain model solves electromagnetic performance, i.e. MFD and torque behaviour.
Findings
The reviewed analytical methodologies are validated with globally accepted FEA using JMAG Commercial FEA Package v. 18.1 which shows good agreement with accuracy. In comparison of analytical methodologies, analysis reveals that sub-domain model not only get rid of multiples techniques for validation purpose but also provide better results by accounting influence of all machine parts which helps to reduce computational complexity, computational time and drive storage with overall accuracy of ∼99%. Furthermore, authors are confident to recommend sub-domain model for initial design stage of SPMCPFSM when higher accuracy and low computational cost are primal requirements.
Practical implications
The model is developed for high-speed brushless AC applications.
Originality/value
The SPMCPFSM enhances electromagnetic performance owing to segmented PMs configuration which makes it different than conventional designs. Moreover, developed analytical methodologies for SPMCPFSM reduce computational time compared with that of FEA.
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