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1 – 10 of 375Marcel Peppel and Stefan Spinler
Last-mile delivery is associated with a negative environmental impact and high costs. The purpose of this paper is to develop an approach to designing stationary parcel locker (SPL…
Abstract
Purpose
Last-mile delivery is associated with a negative environmental impact and high costs. The purpose of this paper is to develop an approach to designing stationary parcel locker (SPL) networks while minimizing both CO2 equivalent (CO2e) emissions and costs during delivery and pick-up.
Design/methodology/approach
This study uses a multinomial logit model to evaluate recipients' willingness to use SPLs based on their availability at home and travel distance. To determine optimal SPL locations, this study formulates a mixed-integer linear programming model.
Findings
The empirical study of different regional clusters reveals that optimal SPL locations can generate cost savings of up to 11.0%. SPLs have a positive impact on total CO2e emission savings in urban areas (i.e. up to 2.5%), but give rise to additional emissions (i.e. 4.6%) in less populated areas due to longer travel distances during the pick-up process.
Originality/value
This paper optimizes SPL locations and the ecological effect of SPLs by minimizing emissions and costs simultaneously. Furthermore, it extends existing discrete choice models by also including recipients' availability at home, increasing the accuracy of recipients' preferences. So far, the effect of SPLs has been studied for metropolitan areas only. A global logistics service provider shared a real dataset which allows us to study seven different regional clusters ranging from rural areas to large cities. Thus, this study contributes to the field of sustainable urban logistics.
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Camilo Carromeu, Debora Barroso Paiva and Maria Istela Cagnin
This paper aims to discuss the motivation and present the evolution from a Software Product Line (SPL) in the e-Gov Web (e-Gov Web SPL) domain to a SPL in the mobile domain (e-Gov…
Abstract
Purpose
This paper aims to discuss the motivation and present the evolution from a Software Product Line (SPL) in the e-Gov Web (e-Gov Web SPL) domain to a SPL in the mobile domain (e-Gov Mobile SPL).
Design/methodology/approach
The evolution was supported by the Product Line UML-Based Software Engineering approach and the feature model.
Findings
The authors were able to observe that it is feasible to evolve from a SPL for the Web platform to a SPL for the mobile platform, with the intent to port existing Web applications to mobile platforms such that users can have access to the main information and are able to interact with the most important functionalities of Web applications in a mobile device.
Research limitations/implications
As for the main limitations, the authors can point out the small number of instantiations performed until the moment with the support of the e-Gov Mobile SPL, what prevented the conduction of an empirical study.
Practical implications
Using e-Gov Mobile SPL, it is possible to reduce development time and cost.
Originality/value
The existing SPLs do not worry about supporting the development of mobile applications corresponding to existing Web applications, as it is desirable to have access to the information and main features of these applications in mobile devices. We obtained some e-Gov Mobile SPL instantiations corresponding to e-Gov Web SPL instantiations to attend the demands of the Brazilian Agricultural Research Corporation Unit situated at Campo Grande, MS, Brazil.
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Luiz Fernando Capretz, Faheem Ahmed, Shereef Al‐Maati and Zaher Al Aghbari
The purpose of this paper is to provide an overview of a pragmatic approach to components off‐the‐shelf (COTS)‐based development. Software product line (SPL) is at the forefront…
Abstract
Purpose
The purpose of this paper is to provide an overview of a pragmatic approach to components off‐the‐shelf (COTS)‐based development. Software product line (SPL) is at the forefront among the techniques for reducing costs, decreasing schedule time, and ensuring commonality of features across a family of products – as COTS are reused in multiple products.
Design/methodology/approach
A disciplined process for SPL development is still needed. This paper proposes the Y‐model for COTS‐based SPL development. The model put forward identifies and elaborates the essential phases and activities of SPL development from COTS‐based repository.
Findings
The Y‐model provides an efficient way of integrating the approaches of SPL and COTS‐based development as a cohesive software development model.
Practical implications
The model has the potential to tremendously increase software engineers' productivity. Thus, software architects, domain engineers and component designers should become aware of how to use these ideas to structure their models and designs.
Originality/value
This paper describes a systematic approach for COTS‐based development that takes into account the cataloguing and retrieval of software assets permeating a process that encompasses all stages of software development, from system product requirements engineering to system deployment.
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Krzysztof Grysa and Artur Maciag
The purpose of this paper is to derive the Trefftz functions (T-functions) for the Pennes’ equation and for the single-phase-lag (SPL) model (hyperbolic equation) with perfusion…
Abstract
Purpose
The purpose of this paper is to derive the Trefftz functions (T-functions) for the Pennes’ equation and for the single-phase-lag (SPL) model (hyperbolic equation) with perfusion and then comparing field of temperature in a flat slab made of skin in the case when perfusion is taken into account, with the situation when a Fourier model is considered. When considering the process of heat conduction in the skin, one needs to take into account the average values of its thermal properties. When in biological bodies relaxation time is of the order of 20 s, the thermal wave propagation appears. The initial-boundary problems for Pennes’ model and SPL with perfusion model are considered to investigate the effect of the finite velocity of heat in the skin, perfusion and thickness of the slab on the rate of the thermal wave attenuation. As a reference model, the solution of the classic Fourier heat transfer equation for the considered problems is calculated. A heat flux has direction perpendicular to the surface of skin, considered as a flat slab. Therefore, the equations depend only on time and one spatial variable.
Design/methodology/approach
First of all the T-functions for the Pennes’ equation and for the SPL model with perfusion are derived. Then, an approximate solutions of the problems are expressed in the form of a linear combination of the T-functions. The T-functions satisfy the equation modeling the problem under consideration. Therefore, approximating a solution of a problem with a linear combination of n T-functions one obtains a function that satisfies the equation. The unknown coefficients of the linear combination are obtained as a result of minimization of the functional that describes an inaccuracy of satisfying the initial and boundary conditions in a mean-square sense.
Findings
The sets of T-functions for the Pennes’ equation and for the SPL model with perfusion are derived. An infinite set of these functions is a complete set of functions and stands for a base functions layout for the space of solutions for the equation used to generate them. Then, an approximate solutions of the initial-boundary problem have been found and compared to find out the effect of finite velocity of heat in the skin, perfusion and thickness of the slab on the rate of the thermal wave attenuation.
Research limitations/implications
The methods used in the literature to find an approximate solution of any bioheat transfer problems are more complicated than the one used in the presented paper. However, it should be pointed out that there is some limitation concerning the T-function method, namely, the greater number of T-function is used, the greater condition number becomes. This limitation usually can be overcome using symbolic calculations or conducting calculations with a large number of significant digits.
Originality/value
The T-functions for the Pennes’ equation and for the SPL equation with perfusion have been reported in this paper for the first time. In the literature, the T-functions are known for other linear partial differential equations (e.g. harmonic functions for Laplace equation), but for the first time they have been derived for the two aforementioned equations. The results are discussed with respect to practical applications.
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Pedro Torres and Mário Augusto
The purpose of this paper is to better understand the connection between culture and entrepreneurship in proposing and testing complex configurations of culturally endorsed…
Abstract
Purpose
The purpose of this paper is to better understand the connection between culture and entrepreneurship in proposing and testing complex configurations of culturally endorsed implicit leadership theories (CLTs) and cultural practices that lead to entrepreneurial behaviour by studying entrepreneurial intentions (EI) and early-stage entrepreneurial activity (TEA) separately.
Design/methodology/approach
Using data from Globe Leadership and Organizational Behavior Effectiveness (GLOBE) and Global Entrepreneurship Monitor (GEM) studies, a sample of 44 countries, and a fuzzy-set qualitative comparative analysis, several models for EI and TEA were developed.
Findings
The main findings provide a way of distinguishing between complex antecedent conditions that are required for each stage of the entrepreneurial realisation. The results empirically show that there is no ideal context – the path to stimulate entrepreneurship that works best for one country does not necessarily works the same for other countries. There are multiple paths to achieve the desired outcome.
Research limitations/implications
The data from the GLOBE study were not completely up to date, the effect of which was minimised by considering data from GEM that respects temporal ordering. Nevertheless, data from GEM suggest that there is a degree of stability in the data over time. Future research could replicate this study with a larger selection of countries and with new data, collected in a different way. Additionally, the inclusion of CLTs proposed in this study opens new opportunities for future research, by providing a new angle to look at the entrepreneurial realisation process.
Practical implications
This study advances research into the association of culture and entrepreneurship, and develops testable models using a configurational approach, thus confirming the suitability of asymmetric configuration analysis for entrepreneurial research. The results expand an understanding of the entrepreneurial process by showcasing the different complex antecedent conditions for EI and TEA. Depending on a country’s cultural profile, policy-makers should invest in the dimensions that enable their society to align with the model that best suits their own culture. The obtained models offer a framework for evaluating new interventions that aim to develop entrepreneurial behaviour in a specific country.
Originality/value
Different configurations showcase that there are alternative paths to achieving high levels of EI and TEA. The differences among the possible configurations for each stage of the entrepreneurial realisation are uncovered. Country profiles are identified, quantified, and then compared providing guidance for policy-makers.
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John McMackin and Patrick Flood
The purpose of this paper is to propose a theoretical framework for the social pillar of lean (SPL), which is a neglected topic in the lean management literature.
Abstract
Purpose
The purpose of this paper is to propose a theoretical framework for the social pillar of lean (SPL), which is a neglected topic in the lean management literature.
Design/methodology/approach
The authors first identify shortcomings in research on the SPL that are attributable to neglect of relevant perspectives in organisational research. The authors then present a theoretical case outlining the factors that should be considered in SPL research, how they relate to one another and how they should be integrated in future studies of lean change implementation.
Findings
The theoretical framework for the SPL proposes a categorisation of factors and their relationships across levels of analysis that are relevant to the SPL. The inclusion of previously neglected perspectives, such as the relational coordination theory, within this framework offers new insights and directions for research.
Practical implications
By emphasising relationships, the SPL framework sheds light on the scale and complexity of the management challenges involved in lean implementation.
Originality/value
The proposed framework promises to enhance the efficacy of lean research by focussing on factors, such as relationships, that are most relevant to lean implementation.
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Mariemma I. Yagüe, Antonio Maña and Javier Lopez
Provide a secure solution for web services (WS). A new interoperable and distributed access control for WS is presented.
Abstract
Purpose
Provide a secure solution for web services (WS). A new interoperable and distributed access control for WS is presented.
Design/methodology/approach
Based on the separation of the access control (AC) and authorization function.
Findings
Mechanisms presented allow seamless integration of external authorization entities in the AC system. The Semantic Policy Language (SPL) developed facilitates specification of policies and semantic policy validation. SPL specifications are modular and can be composed without ambiguity. Also addressed was the problem of the association of policies to resources (WS or their operations) in a dynamic, flexible and automated way.
Research limitations/implications
The ACProxy component is currently under development. Ongoing work is focused on achieving a richer “use control” for some types of WS.
Practical implications
Administrators of WS can specify AC policies and validate them to find syntactic and semantic errors. Components for automated validation of policies at different levels are included. This ensures that the AC policies produce the desired effects, facilitating the creation and maintenance of policies. It also provides mechanisms for the use of interoperable authorizations.
Originality/value
A practical system that provides a secure solution to AC for WS. To the best of one's knowledge, no other system provides mechanisms for semantic validation of policies based on external authorization entities. Likewise, the mechanisms for interoperability of external authorization entities are also novel. The system provides content‐based access control and a secure, decentralized and dynamic solution for authorization that facilitates the management of complex systems and enhances the overall security of the AC.
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The thermo-diffusion analysis of an isotropic cylinder under thermal flux and chemical potential impacts has been discussed. Improvements of Green and Naghdi generalized…
Abstract
Purpose
The thermo-diffusion analysis of an isotropic cylinder under thermal flux and chemical potential impacts has been discussed. Improvements of Green and Naghdi generalized thermoelasticity theory have been proposed.
Design/methodology/approach
Some models with and without energy dissipation have been presented as well as the simple forms of Green–Naghdi (G–N) theories. These novel multi- and single-/dual-phase-lag models are presented to investigate the thermo-diffusion of the solid cylinder. The closed-form solution of thermo-diffusion governing equations of solid cylinder has been obtained to deduce all field variables.
Findings
A comparison study between the simple G–N II and III models and their improved models has been presented. The validations of outcomes are acceptable and so benchmarks are reported to help other investigators in their future comparisons.
Originality/value
The modified Green and Naghdi theories of types II and III are presented to get novel and accurate models of single- and dual-phase-lag of multiterms. The heat of mass diffusion equation as well as the constitutive equations for the stresses and chemical potential of a solid cylinder is added to the present formulation. The system of three differential coupled equations is solved, and all field variables are obtained for the thermal diffusion of the solid cylinder. Some validation examples and applications are presented to compare the simple and modified Green and Naghdi theories of types II and III. Sample plots are illustrated along the radial direction of the solid cylinder. Some results are tabulated to serve as benchmark results for future comparisons with other investigators. The reported and illustrated results show that the simple G–N II and III models yield the largest values of all field quantities. The single-phase-lag models give the smallest values. However, the dual-phase-lag model yields results that are intermediate between those of the simple and single-phase-lag G–N models.
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Mariemma I. Yagüe, Antonio Maña, Javier López, Ernesto Pimentel and José M. Troya
Distributed systems usually contain objects with heterogeneous security requirements that pose important challenges for the underlying security mechanisms and especially in access…
Abstract
Distributed systems usually contain objects with heterogeneous security requirements that pose important challenges for the underlying security mechanisms and especially in access control systems. Access control in distributed systems often relies on centralised security administration. Existing solutions for distributed access control do not provide the flexibility and manageability required. This paper presents the XML‐based secure content distribution (XSCD) infrastructure, which is based on the production of protected software objects that convey contents (software or data) and can be distributed without further security measures because they embed the access control enforcement mechanism. It also provides means for integrating privilege management infrastructures (PMIs). Semantic information is used in the dynamic instantiation and semantic validation of policies. XSCD is scalable, facilitates the administration of the access control system, guarantees the secure distribution of the contents, enables semantic integration and interoperability of heterogeneous sources, provides persistent protection and allows actions (such as payment) to be bound to the access to objects.
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Sooyong Park, Minseong Kim and Vijayan Sugumaran
A software product line (SPL) captures commonalities and variations (C&V) within a family of systems. Although, feature‐oriented approaches have been proposed for building product…
Abstract
A software product line (SPL) captures commonalities and variations (C&V) within a family of systems. Although, feature‐oriented approaches have been proposed for building product lines, none of them provide a systematic approach for identifying features. This paper proposes a domain analysis method for creating SPL based on scenarios, goals and features. In particular, the paper presents a domain requirements model (DRM) that integrates features with goals and scenarios, and a domain requirements modeling method that uses the DRM. This approach has been applied to the home integration system (HIS) domain to demonstrate its feasibility. This approach makes it possible to systematically identify features and provide the rationale for both features and C&V.
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