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Article
Publication date: 1 April 2003

Alastair G. Smith

This study evaluates the retrieval of New Zealand information using three local New Zealand search engines, four major global search engines and three metasearch engines. Searches

1910

Abstract

This study evaluates the retrieval of New Zealand information using three local New Zealand search engines, four major global search engines and three metasearch engines. Searches for NZ topics were carried out on all the search engines, and the relative recall calculated. The local search engines did not achieve higher recall than the global search engines or metasearch engines, but no search engine achieved more than 45 percent recall. Despite the theoretical advantage of searching the databases of several individual search engines, metasearch engines did not achieve higher recall. Of relevant pages for the queries, 36 percent were outside the .nz domain. Implications for searching for geographically specific information, and for evaluation of search engines, are discussed.

Details

Online Information Review, vol. 27 no. 2
Type: Research Article
ISSN: 1468-4527

Keywords

Article
Publication date: 5 March 2018

Xiwen Cai, Haobo Qiu, Liang Gao, Xiaoke Li and Xinyu Shao

This paper aims to propose hybrid global optimization based on multiple metamodels for improving the efficiency of global optimization.

Abstract

Purpose

This paper aims to propose hybrid global optimization based on multiple metamodels for improving the efficiency of global optimization.

Design/methodology/approach

The method has fully utilized the information provided by different metamodels in the optimization process. It not only imparts the expected improvement criterion of kriging into other metamodels but also intelligently selects appropriate metamodeling techniques to guide the search direction, thus making the search process very efficient. Besides, the corresponding local search strategies are also put forward to further improve the optimizing efficiency.

Findings

To validate the method, it is tested by several numerical benchmark problems and applied in two engineering design optimization problems. Moreover, an overall comparison between the proposed method and several other typical global optimization methods has been made. Results show that the global optimization efficiency of the proposed method is higher than that of the other methods for most situations.

Originality/value

The proposed method sufficiently utilizes multiple metamodels in the optimizing process. Thus, good optimizing results are obtained, showing great applicability in engineering design optimization problems which involve costly simulations.

Details

Engineering Computations, vol. 35 no. 1
Type: Research Article
ISSN: 0264-4401

Keywords

Article
Publication date: 1 December 2004

Alastair G. Smith

This paper explores resource discovery issues relating to New Zealand/Aotearoa information on the WWW in the twenty‐first century. Questions addressed are: How do New Zealand…

788

Abstract

This paper explores resource discovery issues relating to New Zealand/Aotearoa information on the WWW in the twenty‐first century. Questions addressed are: How do New Zealand search engines compare with global search engines for finding information relating to New Zealand? Can search engines find everything that is available on the web? What are effective strategies for finding information relating to New Zealand on the web? What is the quality of NZ information on the web? What can librarians do to make NZ information more accessible on the web? Based on a study, it concludes that neither local nor global search engines are by themselves sufficient, and that to maximize retrieval a variety of engines is necessary. The NZ librarian can play a role in ensuring that NZ information is made both available and accessible. Although the paper discusses the situation in New Zealand, the results and conclusions are applicable to other countries.

Details

The Electronic Library, vol. 22 no. 6
Type: Research Article
ISSN: 0264-0473

Keywords

Article
Publication date: 24 September 2020

Marc O. Williams

Extreme weather events are known to be detrimental to well-being, and there is a growing interest in anxiety connected to unfolding climate change. The purpose of this paper is to…

Abstract

Purpose

Extreme weather events are known to be detrimental to well-being, and there is a growing interest in anxiety connected to unfolding climate change. The purpose of this paper is to investigate the global association between information-seeking relating to climate change and mental health.

Design/methodology/approach

By using Big Data from Google searches and website traffic, evidence is presented that worldwide information-seeking for climate change and mental health-related terms are highly correlated. Regression analyses account for seasonal variation that is known to influence online searches for mental health terms.

Findings

There is an association between climate change and mental health-related information-seeking for the period of 2006–2020. This paper proposes causal models to account for the data, with future directions for how these could be tested.

Originality/value

This is the first paper according to the author’s knowledge to demonstrate a strong association between information-seeking for climate change and mental health and highlights the importance of considering mental health issues in the era of rapid climate change.

Details

Journal of Public Mental Health, vol. 20 no. 1
Type: Research Article
ISSN: 1746-5729

Keywords

Book part
Publication date: 15 July 2009

Ciaran Heavey, Richard T. Mowday, Aidan Kelly and Frank Roche

This chapter attempts to reinvigorate scholarly interest in executive scanning by outlining a model to guide future research on executive search within the context of…

Abstract

This chapter attempts to reinvigorate scholarly interest in executive scanning by outlining a model to guide future research on executive search within the context of international strategy. Executive scanning has received considerable empirical attention but only limited theoretical attention. Most of this research has studied scanning as the receipt rather than the search for information. Based on the application of learning theory, we outline a model advancing two broad categories of executive search exploitative and explorative, consisting of six specific search behaviors. We advance search as integral to managerial decisions relating to the various aspects of internationalization, notably choice of location, corporate strategy, and mode of entry. The implications for future research are presented.

Details

Advances in Global Leadership
Type: Book
ISBN: 978-1-84855-256-2

Article
Publication date: 19 June 2020

Deniz Ustun

This study aims to evolve an enhanced butterfly optimization algorithm (BOA) with respect to convergence and accuracy performance for numerous benchmark functions, rigorous…

Abstract

Purpose

This study aims to evolve an enhanced butterfly optimization algorithm (BOA) with respect to convergence and accuracy performance for numerous benchmark functions, rigorous constrained engineering design problems and an inverse synthetic aperture radar (ISAR) image motion compensation.

Design/methodology/approach

Adaptive BOA (ABOA) is thus developed by incorporating spatial dispersal strategy to the global search and inserting the fittest solution to the local search, and hence its exploration and exploitation abilities are improved.

Findings

The accuracy and convergence performance of ABOA are well verified via exhaustive comparisons with BOA and its existing variants such as improved BOA (IBOA), modified BOA (MBOA) and BOA with Levy flight (BOAL) in terms of various precise metrics through 15 classical and 12 conference on evolutionary computation (CEC)-2017 benchmark functions. ABOA has outstanding accuracy and stability performance better than BOA, IBOA, MBOA and BOAL for most of the benchmarks. The design optimization performance of ABOA is also evaluated for three constrained engineering problems such as welded beam design, spring design and gear train design and the results are compared with those of BOA, MBOA and BOA with chaos. ABOA, therefore, optimizes engineering designs with the most optimal variables. Furthermore, a validation is performed through translational motion compensation (TMC) of the ISAR image for an aircraft, which includes blurriness. In TMC, the motion parameters such as velocity and acceleration of target are optimally predicted by the optimization algorithms. The TMC results are elaborately compared with BOA, IBOA, MBOA and BOAL between each other in view of images, motion parameter and numerical image measuring metrics.

Originality/value

The outperforming results reflect the optimization and design successes of ABOA which is enhanced by establishing better global and local search abilities over BOA and its existing variants.

Article
Publication date: 4 April 2016

Nianyin Zeng, Hong Zhang, Yanping Chen, Binqiang Chen and Yurong Liu

This paper aims to present a novel particle swarm optimization (PSO) based on a non-homogeneous Markov chain and differential evolution (DE) for path planning of intelligent robot…

Abstract

Purpose

This paper aims to present a novel particle swarm optimization (PSO) based on a non-homogeneous Markov chain and differential evolution (DE) for path planning of intelligent robot when having obstacles in the environment.

Design/methodology/approach

The three-dimensional path surface of the intelligent robot is decomposed into a two-dimensional plane and the height information in z axis. Then, the grid method is exploited for the environment modeling problem. After that, a recently proposed switching local evolutionary PSO (SLEPSO) based on non-homogeneous Markov chain and DE is analyzed for the path planning problem. The velocity updating equation of the presented SLEPSO algorithm jumps from one mode to another based on the non-homogeneous Markov chain, which can overcome the contradiction between local and global search. In addition, DE mutation and crossover operations can enhance the capability of finding a better global best particle in the PSO method.

Findings

Finally, the SLEPSO algorithm is successfully applied to the path planning in two different environments. Comparing with some well-known PSO algorithms, the experiment results show the feasibility and effectiveness of the presented method.

Originality/value

Therefore, this can provide a new method for the area of path planning of intelligent robot.

Details

Assembly Automation, vol. 36 no. 2
Type: Research Article
ISSN: 0144-5154

Keywords

Article
Publication date: 1 January 2014

Wenjia Yang, Haijuan Zhou and Yuling Li

The purpose of this paper is to report the investigations on the potential of a new evolutionary algorithm based on probabilistic models – the quantum-inspired evolutionary…

Abstract

Purpose

The purpose of this paper is to report the investigations on the potential of a new evolutionary algorithm based on probabilistic models – the quantum-inspired evolutionary algorithm (QEA) in solving inverse problems.

Design/methodology/approach

An improved QEA.

Findings

The proposed algorithm is an efficient and robust global optimizer for solving inverse problems.

Originality/value

To enhance the convergence speed without compromising the diversity performances of the populations, a new definition of global information sharing is introduced and implemented. To guarantee the balance between exploration and exploitation searches, a different migration strategy and formula, as well as a novel formulation for adaptively updating the rotation angle, are developed.

Details

COMPEL: The International Journal for Computation and Mathematics in Electrical and Electronic Engineering, vol. 33 no. 1/2
Type: Research Article
ISSN: 0332-1649

Keywords

Article
Publication date: 2 October 2017

Shanjun Chen and Haibin Duan

The purpose of this paper is to propose an improved optimization method for image matching problem, which is based on multi-scale Gaussian mutation pigeon-inspired optimization…

Abstract

Purpose

The purpose of this paper is to propose an improved optimization method for image matching problem, which is based on multi-scale Gaussian mutation pigeon-inspired optimization (MGMPIO) algorithm, with the objective of accomplishing the complicated image matching quickly.

Design/methodology/approach

The hybrid model of multi-scale Gaussian mutation (MGM) mechanism and pigeon-inspired optimization (PIO) algorithm is established for image matching problem. The MGM mechanism is a nonlinear model, which can adjust the position of pigeons by mutation operation. In addition, the variable parameter (VP) mechanism is exploited to adjust the map and compass factor of the original PIO. Low-cost quadrotor, a type of electric multiple rotorcraft, is used as a carrier of binocular camera to obtain the images.

Findings

This work improved the PIO algorithm by modifying the search strategy and adding some limits, so that it can have better performance when applied to the image matching problem. Experimental results show that the proposed method demonstrates satisfying performance in convergence speed, robustness and stability.

Practical implications

The proposed MGMPIO algorithm can be easily applied to solve practical problems and accelerate convergence speed of the original PIO, and thus enhancing the speed of matching process, which will considerably increase the effectiveness of algorithm.

Originality/value

A hybrid model of the MGM mechanism and PIO algorithm is proposed for image matching problem. The VP mechanism and low-cost quadrotor is also utilized in image matching problem.

Details

Aircraft Engineering and Aerospace Technology, vol. 89 no. 6
Type: Research Article
ISSN: 1748-8842

Keywords

Article
Publication date: 23 September 2013

Mingyu Li, Bo Wu, Pengxing Yi, Chao Jin, Youmin Hu and Tielin Shi

In the high-speed trains (HSTs) production process, assembly sequence planning (ASP) problems is an extremely core issue. ASP problems influence the economic cost, amount of…

Abstract

Purpose

In the high-speed trains (HSTs) production process, assembly sequence planning (ASP) problems is an extremely core issue. ASP problems influence the economic cost, amount of workers and the working time in the assembly process, seriously. In the design process of HSTs, the assembly sequence is usually given by experience, and the correctness of the assembly sequence is difficult to guarantee by experience and low effectiveness. The ASP based on improved discrete particle swarm optimization (IDPSO) algorithm was proposed to address these issues.

Design/methodology/approach

In view of the local convergence problem with basic DPSO in ASP, this paper presents an IDPSO, in which a chosen strategy of global optimal particle is introduced in, to solve the ASP problems in the assembly process of HSTs operation panel. The geometric feasibility, the assembly stability, and the number of assembly orientation changes of the assembly are chosen to be the optimization objective. Furthermore, the influences of the population size, the weight coefficient, and the learning factors to the stability and efficiency of IDPSO algorithm were discussed.

Findings

The results show that the IDPSO algorithm can obtain the global optimum efficiently, which is proved to be a more useful method for solving ASP problems than basic DPSO. The IDPSO approach could reduce the working time and economic cost of ASP problems in HSTs significantly.

Practical implications

The method may save the economic cost, reduce the amount of workers and save the time in the assembly process of HSTs. And also may change the method of ASP in design and manufacturing process, and make the production process in HSTs more efficiently.

Originality/value

A chosen strategy of global optimal particle is presented, which can overcome the local convergence problem with basic DPSO for solving ASP problems.

1 – 10 of over 82000