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1 – 10 of 533“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…
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.
Frédéric Moens and Christelle Wervaecke
Today, the design process of high‐lift configurations in industry mainly relies on experts' knowledge, and lacks a simple exploration of the design space. Therefore, the…
Abstract
Purpose
Today, the design process of high‐lift configurations in industry mainly relies on experts' knowledge, and lacks a simple exploration of the design space. Therefore, the introduction of high‐fidelity tools in an optimization chain is now envisaged. The purpose of this paper is to define and solve a realistic high‐lift design problem by the use of a constrained evolutionary algorithm, coupled to a Navier‐Stokes (RANS) solver. The complete optimization (shape and settings) of a 3‐element configuration has been carried out for landing and take‐off configurations using a sequential approach.
Design/methodology/approach
In a first step, the elements' shapes and settings of the landing configuration have been optimized simultaneously. Then, shapes have been frozen and settings have been optimized for take‐off conditions. The flow evaluation during the optimization process is made through 2.5D Navier‐Stokes computations on chimera grids. The optimization technique used is an evolutionary algorithm, with a dynamic adaptation of the covariance matrix (CMA‐ES). Geometric and aerodynamic constraints have been considered through a dynamic penalization technique of the cost function.
Findings
Solutions obtained have been analyzed and compared to the reference initial configuration. In term of cost functions improvement, 5.71 per cent drag reduction has been obtained for landing, and 2.89 per cent improvement on climb index at take‐off.
Practical implications
Compared to the global optimization process, the use of a sequential approach can be quite efficient.
Originality/value
This paper presents a first step for the introduction of recent advanced methods into a design process of high‐lift configurations in an industrial environment.
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Sara Dassouli, Virginia Bodolica, Harit Satt and Mohamed M'hamdi
This paper aims to examine the specific role that partnerships play in the relationship between adaptation strategy, international experience, and export performance of handicraft…
Abstract
Purpose
This paper aims to examine the specific role that partnerships play in the relationship between adaptation strategy, international experience, and export performance of handicraft firms in an emerging country setting. The authors' purpose is to identify the key factors that may contribute to the success of export activities of small handicraft companies in international markets.
Design/methodology/approach
Drawing on a non-probability sampling technique, the authors collected survey data from 410 handicraft companies located in Morocco. The authors' conceptual model, which draws on the network theory, was tested using covariance-based Structural Equation Modeling by means of AMOS 24 Software.
Findings
The results indicate that adaptation marketing strategy and partnerships impact positively the export performance of handicraft firms. Partnerships also play an intermediary role by partially (fully) mediating the relationship between adaptation strategy (international experience) and export performance.
Practical implications
This study may assist marketers and entrepreneurs in handicraft companies to better understand the causal relationship between adaptation strategy, marketing experience and export performance of entrepreneurs' firms. Managers in these companies should be aware of the importance that partnerships play in boosting the export performance through marketing practices and experience.
Originality/value
The authors' paper contributes to the scant literature on the adaptation marketing strategy and export performance and the intermediary role of partnerships in the specific context of handicraft businesses operating in North African emerging markets, namely Morocco.
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Babitha Thangamalar J. and Abudhahir A.
This study aims to propose optimised function-based evolutionary algorithms in this research to effectively replace the traditional electronic circuitry used in linearising…
Abstract
Purpose
This study aims to propose optimised function-based evolutionary algorithms in this research to effectively replace the traditional electronic circuitry used in linearising constant temperature anemometer (CTA) and Microbridge mass flow sensor AWM 5000.
Design/methodology/approach
The proposed linearisation technique effectively uses the ratiometric function for the linearisation of CTA and Microbridge mass flow sensor AWM 5000. In addition, the well-known transfer relation, namely, the King’s Law is used for the linearisation of CTA and successfully implemented using LabVIEW 7.1.
Findings
Investigational results unveil that the proposed evolutionary optimised linearisation technique performs better in linearisation of both CTA and Mass flow sensors, and hence finds applications for computer-based flow measurement/control systems.
Originality/value
The evolutionary optimisation algorithms such as the real-coded genetic algorithm, particle swarm optimisation algorithm, differential evolution algorithm and covariance matrix adopted evolutionary strategy algorithm are used to determine the optimal values of the parameters present in the proposed ratiometric function. The performance measures, namely, the full-scale error and mean square error are used to analyse the overall performance of the proposed approach is compared to a state of art techniques available in the literature.
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In this paper, I propose an algorithm combining adaptive sampling and Reversible Jump MCMC to deal with the problem of variable selection in time-varying linear model. These types…
Abstract
In this paper, I propose an algorithm combining adaptive sampling and Reversible Jump MCMC to deal with the problem of variable selection in time-varying linear model. These types of model arise naturally in financial application as illustrated by a motivational example. The methodology proposed here, dubbed adaptive reversible jump variable selection, differs from typical approaches by avoiding estimation of the factors and the difficulties stemming from the presence of the documented single factor bias. Illustrated by several simulated examples, the algorithm is shown to select the appropriate variables among a large set of candidates.
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Hanxiang Xu, Shihui Guo, Junfeng Yao and Nadia Magnenat Thalmann
In the process of robot shell design, it is necessary to match the shape of the input 3D original character mesh model and robot endoskeleton, in order to make the input model fit…
Abstract
Purpose
In the process of robot shell design, it is necessary to match the shape of the input 3D original character mesh model and robot endoskeleton, in order to make the input model fit for robot and avoid collision. So, the purpose of this paper is to find an object of reference, which can be used for the process of shape matching.
Design/methodology/approach
In this work, the authors propose an interior bounded box (IBB) approach that derives from oriented bounding box (OBB). This kind of box is inside the closed mesh model. At the same time, it has maximum volume which is aligned with the object axis but is enclosed by all the mesh vertices. Based on the IBB of input mesh model and the OBB of robot endoskeleton, the authors can complete the process of shape matching. In this paper, the authors use an evolutionary algorithm, covariance matrix adaptation evolution strategy (CMA-ES), to approximate the IBB based on skeleton and symmetry of input character mesh model.
Findings
Based on the evolutionary algorithm CMA-ES, the optimal position and scale information of IBB can be found. The authors can obtain satisfactory IBB result after this optimization process. The output IBB has maximum volume and is enveloped by the input character mesh model as well.
Originality/value
To the best knowledge of the authors, the IBB is first proposed and used in the field of robot shell design. Taking advantage of the IBB, people can quickly obtain a shell model that fit for robot. At the same time, it can avoid collision between shell model and the robot endoskeleton.
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Amirali Kani, Duncan K.H. Fong and Wayne S. DeSarbo
This paper aims to examine the evolution of a competitive market structure over time through the lens of competitive group membership dynamics.
Abstract
Purpose
This paper aims to examine the evolution of a competitive market structure over time through the lens of competitive group membership dynamics.
Design/methodology/approach
A new hidden Markov modeling approach is devised that accounts for the three sources of competitive heterogeneity involving managerial strategy, corporate performance and the impact of strategy on performance. In addition, some observed “entry” and “exit” states are considered to model firms’ entry into and exit from the market. The proposed model is illustrated with an investigation of the US banking industry based on a data set created from the COMPUSTAT database. This paper estimated the model within the Bayesian framework and devised a reversible jump Markov chain Monte Carlo estimation procedure to determine the number of latent competitive groups and uncover the characteristics of each group.
Findings
This paper shows that the US banking industry, contrary to the prior findings of having a relatively stable structure, has, in fact, gone through dramatic changes in the past number of decades.
Originality/value
Contrary to prior work that has primarily focused on managerial strategy to study market evolutions, the competitive groups perspective accounts for all three sources of intra-industry competitive heterogeneity. In addition, unlike prior research, the analysis is not limited to firms remaining in the panel of study for the entire observation period. Such limitation results in missing the various changes that occur in the competitive market structure because of the new entrants or the struggling firms that do not survive in the market.
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The analysis of strategic groups has important implications for marketing in order to identify a firm’s competitive position. Aims to analyse the development of the competence in…
Abstract
The analysis of strategic groups has important implications for marketing in order to identify a firm’s competitive position. Aims to analyse the development of the competence in an industry. Hypothesizes that the analysis of strategic groups is only meaningful when it is determined that the groupings obtained are not random events within a particular industry. Uses multivariate statistical tests to determine the stable sub‐periods, the strategic groups, and their dynamic characteristics over the years. Applies this technique to the Spanish banking sector and detects a relative intra‐industrial instability, and a significant change in the number and strategy of the identified groups with the passing of time.
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The analysis of strategic groups has important implications for marketing in order to identify a firm’s competitive position. Aims to analyse the development of the competence in…
Abstract
The analysis of strategic groups has important implications for marketing in order to identify a firm’s competitive position. Aims to analyse the development of the competence in an industry. Hypothesizes that the analysis of strategic groups is only meaningful when it is determined that the groupings obtained are not random events within a particular industry. Uses multivariate statistical tests to determine the stable sub‐periods, the strategic groups, and their dynamic characteristics over the years. Applies this technique to the Spanish banking sector and detects a relative intra‐industrial instability, and a significant change in the number and strategy of the identified groups with the passing of time.
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Ignazio Maria Viola, Vincent Chapin, Nicola Speranza and Marco Evangelos Biancolini
There is an increasing interest in airfoils that modify their shape to adapt at the flow conditions. As an example of application, the authors search the optimal 4-digit NACA…
Abstract
Purpose
There is an increasing interest in airfoils that modify their shape to adapt at the flow conditions. As an example of application, the authors search the optimal 4-digit NACA airfoil that maximizes the lift-over-drag ratio for a constant lift coefficient of 0.6, from Re = 104 to 3 × 106.
Design/methodology/approach
The authors consider a γ−Reθt transition model and a κ – ω SST turbulence model with a covariance matrix adaptation evolutionary optimization algorithm. The shape is adapted by radial basis functions mesh morphing using four parameters (angle of attack, thickness, camber and maximum camber position). The objective of the optimization is to find the airfoil that enables a maximum lift-over-drag ratio for a target lift coefficient of 0.6.
Findings
The computation of the optimal airfoils confirmed the expected increase with Re of the lift-over-drag ratio. However, although the observation of efficient biological fliers suggests that the thickness increases monotonically with Re, the authors find that it is constant but for a 1.5 per cent step increase at Re = 3 × 105.
Practical implications
The authors propose and validate an efficient high-fidelity method for the shape optimization of airfoils that can be adopted to define robust and reliable industrial design procedures.
Originality/value
The authors show that the difference in the numerical error between two-dimensional and three-dimensional simulations is negligible, and that the numerical uncertainty of the two-dimensional simulations is sufficiently small to confidently predict the aerodynamic forces across the investigated range of Re.
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