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Article
Publication date: 10 May 2021

Zachary Hornberger, Bruce Cox and Raymond R. Hill

Large/stochastic spatiotemporal demand data sets can prove intractable for location optimization problems, motivating the need for aggregation. However, demand aggregation…

Abstract

Purpose

Large/stochastic spatiotemporal demand data sets can prove intractable for location optimization problems, motivating the need for aggregation. However, demand aggregation induces errors. Significant theoretical research has been performed related to the modifiable areal unit problem and the zone definition problem. Minimal research has been accomplished related to the specific issues inherent to spatiotemporal demand data, such as search and rescue (SAR) data. This study provides a quantitative comparison of various aggregation methodologies and their relation to distance and volume based aggregation errors.

Design/methodology/approach

This paper introduces and applies a framework for comparing both deterministic and stochastic aggregation methods using distance- and volume-based aggregation error metrics. This paper additionally applies weighted versions of these metrics to account for the reality that demand events are nonhomogeneous. These metrics are applied to a large, highly variable, spatiotemporal demand data set of SAR events in the Pacific Ocean. Comparisons using these metrics are conducted between six quadrat aggregations of varying scales and two zonal distribution models using hierarchical clustering.

Findings

As quadrat fidelity increases the distance-based aggregation error decreases, while the two deliberate zonal approaches further reduce this error while using fewer zones. However, the higher fidelity aggregations detrimentally affect volume error. Additionally, by splitting the SAR data set into training and test sets this paper shows the stochastic zonal distribution aggregation method is effective at simulating actual future demands.

Originality/value

This study indicates no singular best aggregation method exists, by quantifying trade-offs in aggregation-induced errors practitioners can utilize the method that minimizes errors most relevant to their study. Study also quantifies the ability of a stochastic zonal distribution method to effectively simulate future demand data.

Details

Journal of Defense Analytics and Logistics, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 2399-6439

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Article
Publication date: 1 February 2003

J.B. Kim and D.Y. Yang

The initiation and growth of wrinkles are influenced by many factors such as stress ratios, the mechanical properties of the sheet material, the geometry of the workpiece…

Abstract

The initiation and growth of wrinkles are influenced by many factors such as stress ratios, the mechanical properties of the sheet material, the geometry of the workpiece, contact condition, etc. It is difficult to analyze wrinkling initiation and growth while considering all the factors because the effects of the factors are very complex and studies of wrinkling behavior may show a wide scattering of data even for small deviations in factors. The finite element analyses of wrinkling initiation and growth in sheet metal forming process provide detailed information about the wrinkling behavior of sheet metal. The direct analysis of wrinkling initiation and growth, however, brings about a little difficulty in complex industrial problems because it requires large memory size and long computation time. From the industrial viewpoint of tooling design, therefore, readily available information on the possibility and location of wrinkling is sometimes more preferable to detailed and time‐consuming analysis results. In the present study, in order to give such readily available information on wrinkling initiation, the wrinkling factor, which shows the locations and relative possibility of wrinkling initiation, is proposed as a convenient tool of relative wrinkling estimation based on the energy criterion. The reliability of the wrinkling factor is verified through the buckling analyses of sheet strips. The location and relative possibility of wrinkling initiation are predicted by calculating the wrinkling factor in various sheet metal forming processes such as cylindrical cup deep drawing, spherical cup deep drawing, and elliptical cup deep drawing. Finally, the wrinkling factor proposed in the present study is also implemented in the prediction of wrinkling in the door inner stamping process. For verification of the calculated wrinkling factor, detailed zone analyses with fine meshes are carried out for the regions where wrinkling is predicted.

Details

Engineering Computations, vol. 20 no. 1
Type: Research Article
ISSN: 0264-4401

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Article
Publication date: 30 November 2018

Issam Kouatli

The university social responsibility (USR) is still in embryonic stage compared to corporate social responsibility (CSR) which is still debatable by researchers. The…

Abstract

Purpose

The university social responsibility (USR) is still in embryonic stage compared to corporate social responsibility (CSR) which is still debatable by researchers. The purpose of this paper is to propose the contemporary dimension (on top of teaching and research dimensions) of USR in most educational institutes. Based on this new definition, a proposal of a mechanism to quantify USR sustainability was presented.

Design/methodology/approach

Based on a review of the theme of the CSR with the inter-related recent research on USR with researchers perspectives, characteristics of USR were identified and incorporated in the proposed newly definition of USR. The new definition takes into account the interrelationship of university–corporate communication and create shared value (CSV) principle, as well as the knowledgeability and sustainability.

Findings

Based on the review of most active research in the USR development and the concluded contemporary definition of USR, this paper proposes a new extended version of sustainability suitable for educational institutes, where it is composed of different zones, and each zone was defined in terms of value of sustainability with associated knowledgeability in each zone. The Green Cloud project was taken as a vehicle to demonstrate collaboration between a university and cloud service provider located in Middle East (Dubai). Sustainability quantification was provided with hypothetical numbers to illustrate the technique.

Research limitations/implications

This paper is focused on University-specific social responsibility rather than general CSR. The proposed contemporary definition of the USR is a hybrid of a mutated latest research on CSR as well as cascaded recent development on USR. The view of this new definition can have different arguments depending on the ideology (communitarianism as opposed to individualism) adopted by specific university admiration of the objective of social responsibility which is sometimes driven by the political and strategic views of countries and the regions. However, the proposed sustainability zone-split between the CSV type of projects and the reputation values (described via hypothetical example) can minimize the gap between the two ideologies.

Originality/value

This paper attempts to provide a universally acceptable definition of the USR based on different points of views of researchers and tries to accommodate both ideologies toward social responsibility into one coherent framework. The sustainability Venn diagram was extended and made suitable for educational institutes. This approach facilitates the mechanism of quantifying the value of sustainability of a university or educational institutes. Hypothetical “Green Cloud” project was used as a mechanism to show the quantification process.

Details

Social Responsibility Journal, vol. 15 no. 7
Type: Research Article
ISSN: 1747-1117

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Article
Publication date: 21 November 2008

Michael Rehm and Olga Filippova

The purpose of this paper is to explore and quantify the impact of geographically defined school zones on house prices in New Zealand.

Abstract

Purpose

The purpose of this paper is to explore and quantify the impact of geographically defined school zones on house prices in New Zealand.

Design/methodology/approach

This paper develops a series of hedonic pricing models to analyse 10,000 house sales transactions over a 21‐year period within a compact group of inner Auckland suburbs, which represents the epicentre of the school zoning debate in New Zealand. The study diverts from past research, which mainly focuses on school quality measures such as standardised test scores, and instead analyses the comprehensive price impacts of access to popular state schools. Its unique approach employs a geographic information system to divide the study area into effective school zones and then further subdivide into suburbs, thus offering a vital indicator of internal validity.

Findings

The study's findings indicate that the influence of school zoning on house prices is not uniform and the variation in price effects is largely a function of the uncertainty of future zone boundary definitions. Although some “in‐zone” suburbs have enjoyed accelerated house price growth following the reintroduction of zoning in 2000, peripheral suburbs’ price premiums have diminished.

Originality/value

In contrast to standard hedonic studies on school quality, this paper offers an innovative approach that integrates geography to solve what is essentially a spatial economic problem.

Details

International Journal of Housing Markets and Analysis, vol. 1 no. 4
Type: Research Article
ISSN: 1753-8270

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Article
Publication date: 1 April 1990

E. Powell Robinson and Ronald K. Satterfield

The interaction between customer service policy,as defined by the in‐transit delivery lead time component of the order cycle and the design of least cost distribution…

Abstract

The interaction between customer service policy, as defined by the in‐transit delivery lead time component of the order cycle and the design of least cost distribution systems is examined. A broader view of the distribution system design problem than previously taken in the literature is given and both the firm′s network strategy (number and location of facilities) and transportation strategy (mode/method of shipment) into the planning process are incorporated. Procedures for incorporating customer service policy into the distribution system design process are discussed; the effect of alternate customer service definitions on the least cost distribution system design are evaluated; and new mathematical procedures that integrate customer service policy, network strategy and transportation strategy into a comprehensive planning model are provided. Example problems in the text illustrate the potential benefit of accepting premium transportation costs in return for reduced facility proximity to customers.

Details

International Journal of Physical Distribution & Logistics Management, vol. 20 no. 4
Type: Research Article
ISSN: 0960-0035

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Book part
Publication date: 24 May 2007

Frederic Carluer

“It should also be noted that the objective of convergence and equal distribution, including across under-performing areas, can hinder efforts to generate growth

Abstract

“It should also be noted that the objective of convergence and equal distribution, including across under-performing areas, can hinder efforts to generate growth. Contrariwise, the objective of competitiveness can exacerbate regional and social inequalities, by targeting efforts on zones of excellence where projects achieve greater returns (dynamic major cities, higher levels of general education, the most advanced projects, infrastructures with the heaviest traffic, and so on). If cohesion policy and the Lisbon Strategy come into conflict, it must be borne in mind that the former, for the moment, is founded on a rather more solid legal foundation than the latter” European Commission (2005, p. 9)Adaptation of Cohesion Policy to the Enlarged Europe and the Lisbon and Gothenburg Objectives.

Details

Managing Conflict in Economic Convergence of Regions in Greater Europe
Type: Book
ISBN: 978-1-84950-451-5

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Article
Publication date: 12 January 2015

Johan Sandberg, Jonny Holmström, Nannette Napier and Per Levén

Although the potential of innovation networks that involve both university and industry actors is great variances in cultures, goals and knowledge poses significant…

Abstract

Purpose

Although the potential of innovation networks that involve both university and industry actors is great variances in cultures, goals and knowledge poses significant challenges. To better understand management of such innovation networks, the authors investigate different strategies for balancing diversity. The paper aims to discuss these issues.

Design/methodology/approach

In this multiple case study, the authors draw on network and trading zone theory to examine the strategies of four research centers that govern university-industry innovation networks.

Findings

The authors provide empirically grounded descriptions of strategies for balancing diversity in innovation processes, extend previous theorizations by suggesting two types of trading zones (transformative and performative), and identify four strategy configuration dimensions (means of knowledge trade, tie configuration, knowledge mobility mechanisms and types of trust).

Research limitations/implications

Further research is needed on transferability of results when, e.g. cultural collaboration and communication patterns change, and performance implications of different configurations. The research provides conceptual tools for future research on the impact of different diversity strategies.

Practical implications

The findings point to the importance of identifying desired types of innovation outcomes and designing the appropriate level of diversity. To implement the selected strategy, managers need to configure communication channels and strength of relationships, establish associated capacity for knowledge transfer and build appropriate levels of trust.

Originality/value

While extant research has provided a solid understanding of benefits from diversity in boundary spanning innovation processes, this paper outlines strategies for managing associated challenges.

Details

European Journal of Innovation Management, vol. 18 no. 1
Type: Research Article
ISSN: 1460-1060

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Article
Publication date: 1 March 2004

G.A. D'Addetta, E. Ramm, S. Diebels and W. Ehlers

In this paper, a new homogenization technique for the determination of dynamic and kinematic quantities of representative elementary volumes (REVs) in granular assemblies…

Abstract

In this paper, a new homogenization technique for the determination of dynamic and kinematic quantities of representative elementary volumes (REVs) in granular assemblies is presented. Based on the definition of volume averages, expressions for macroscopic stress, couple stress, strain and curvature tensors are derived for an arbitrary REV. Discrete element model simulations of two different test set‐ups including cohesionless and cohesive granular assemblies are used as a validation of the proposed homogenization technique. A non‐symmetric macroscopic stress tensor, as well as couple stresses are obtained following the proposed procedure, even if a single particle is described as a standard continuum on the microscopic scale.

Details

Engineering Computations, vol. 21 no. 2/3/4
Type: Research Article
ISSN: 0264-4401

Keywords

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Article
Publication date: 19 March 2020

Hassan Darabi, Homa Irani Behbahani, Samin Shokoohi and Saman Shokoohi

The integrity of heritage and landscape hinges on protection and restoration policies. Such policies are implemented through the determination of buffer zones that most of…

Abstract

Purpose

The integrity of heritage and landscape hinges on protection and restoration policies. Such policies are implemented through the determination of buffer zones that most of them are mainly based on the self-absorbed view, which isolates cultural sites from the community, instead of the more inclusive perception-based view. This study used perceptions as a base in identifying buffer zones in Anahita Temple, in comparison with previous study.

Design/methodology/approach

Accordingly, two parallel and qualitative methods were implemented. First, the site inventory approach was used to determine physical buffer zone, and then historical and temporal perceptions were used to determine a perception-based one. In addition, integrated buffer zone was defined based on two approaches. Finally, the participatory importance and performance analysis were proposed in order to conservation strategies formulation.

Findings

The results indicated that a physical buffer zone isolates the historical site from its landscape, thereby presenting challenges. By contrast, constructing a perception-based one not only maintains the integrity of the landscape but also creates correspondence between the landscape and people's mental map of the site.

Practical implications

Maintaining the site's integrity is expected to encourage participation from the local community and fuel more effective conservation efforts but it also introduces challenges given the need to impose new regulations.

Originality/value

Despite various studies on role of perception in Historical Landscape, less attention has been paid to the role of perception in definition of heritage buffer zone. Therefore, the main goal is to develop a framework to determine the buffer zone of heritage sites by providing a sample.

Details

Journal of Cultural Heritage Management and Sustainable Development, vol. 10 no. 3
Type: Research Article
ISSN: 2044-1266

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Article
Publication date: 1 May 2001

J.N. Reddy and S. Mukherjee

A practical method for localized h ‐adaptive error estimation is presented based on interior estimates of the Galerkin solution. A previously published hybrid interior…

Abstract

A practical method for localized h ‐adaptive error estimation is presented based on interior estimates of the Galerkin solution. A previously published hybrid interior error estimator is revisited here and proper bounds are established. It is shown that in the present form of the estimator both the local accelerated convergence and the global superconvergence properties are maintained. The estimator is based on energy norms and all the computations are based on groups of connected elements. The resulting form of the estimator is shown to be simpler and more amenable to computational implementation than the previous one. Two plane elasticity problems are chosen as examples and both structured and h ‐adaptive global initial meshes are considered to compute the convergence characteristics of the solution in a few preselected zones. The solutions are benchmarked against conventional global h ‐adaptive superconvergent error estimators.

Details

Engineering Computations, vol. 18 no. 3/4
Type: Research Article
ISSN: 0264-4401

Keywords

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