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Article
Publication date: 22 July 2024

Ningjun Xu, Miaomiao Sun, Zhangsong Shi and Jin Zhang

Firepower conflicts usually decay the firepower plan's enforceability, thus incurring high survival risks. Previous studies have shown little attention to avoiding firepower…

Abstract

Purpose

Firepower conflicts usually decay the firepower plan's enforceability, thus incurring high survival risks. Previous studies have shown little attention to avoiding firepower conflicts during the weapon target assignment process. This research proposes a new constrained optimization model named Firepower Conflict Free WTA (FCFWTA) and designs a Survival Evolution (SE) strategy for Artificial Fish Swarm Algorithm (AFSA) to solve the complex constrained WTA problem. In this way, commanders can get more reliable firepower assignment decision support.

Design/methodology/approach

A new constrained optimization model named Firepower Conflict Free WTA (FCFWTA) is constructed. FCFWTA unifies firepower decision variables for different kinds of weapons and takes the firing time point as a clue for firepower conflict checking. The objective function of FCFWTA is the weighted sum of the minimum threat value rest rate (RRTV), maximum hit efficiency (HE) and minimum latest interception time percentage (PLT). Since previous algorithms do not check and resolve intermediate results during optimization, an adapted strategy named Survival Evolution is designed. It enables making full use of the limited firepower without adjusting the coordination scenario in execution.

Findings

The proposed method offers significant advantages in two aspects. Firstly, it effectively enhances the optimization results of WTA in the absence of firepower conflicts. Evidence from Figure. 6 confirms that without the proposed method, there is a high likelihood of generating invalid outcomes. After implementing firepower conflict check and resolution, there is a substantial degradation in the objective function value. Secondly, the method excels at equitably distributing firepower among multiple targets while also enhancing the overall interception probability, irrespective of the varying complexities presented by different scenarios. This ability to maintain balance and efficiency is crucial for tackling defense-related issues.

Research limitations/implications

Specifically, SE is tailored for MWMT problem under time and space constraints. This approach diverges significantly from conventional MWMT research, which typically focuses solely on ammunition quantity or firing range. Consequently, the primary objective was to verify the efficacy of this method. Test results indicated that SE does not exhibit uniform performance across different algorithms; while it significantly enhances the efficacy with PSO and AFSA, its influence is considerably diminished when applied to GA. It might be attributed to the inherent randomness associated with crossover and mutation, which can increase the likelihood of firepower conflicts, coupled with SE's reorganization of the chromosome.

Originality/value

The work described was original research that has not been published previously, and not under consideration for publication elsewhere, in whole or in part.

Details

Engineering Computations, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0264-4401

Keywords

Article
Publication date: 1 September 1999

M. Chiampi, M. Repetto, V. Chechurin, A. Kalimov and L. Leboucher

A simulation of the motion of molten aluminium inside an electrolytic cell is presented. Since the driving term of the aluminium motion is the Lorentz (j × B) body force acting…

Abstract

A simulation of the motion of molten aluminium inside an electrolytic cell is presented. Since the driving term of the aluminium motion is the Lorentz (j × B) body force acting within the fluid,this problem involves the solution of the magneto‐hydro‐dynamic equations. Different solver modules for the magnetic field computation and for the fluid motion simulation are coupled together. The interactions of all these are presented and discussed.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 18 no. 3
Type: Research Article
ISSN: 0332-1649

Keywords

Article
Publication date: 1 September 2002

Michele Ciofalo and Fabrizio Cricchio

The buoyancy‐driven magnetohydrodynamic flow in a cubic enclosure was investigated by three‐dimensional numerical simulation. The enclosure was volumetrically heated by a uniform…

Abstract

The buoyancy‐driven magnetohydrodynamic flow in a cubic enclosure was investigated by three‐dimensional numerical simulation. The enclosure was volumetrically heated by a uniform power density and cooled along two opposite vertical walls, all remaining walls being adiabatic. A uniform magnetic field was applied orthogonally to the gravity vector and to the temperature gradient. The Prandtl number was 0.0321 (characteristic of Pb–17Li at 300°C), the Rayleigh number was 104, and the Hartmann number was made to vary between 0 and 2×103. The steady‐state Navier–Stokes equations, in conjunction with a scalar transport equation for the fluid's enthalpy and with the Poisson equation for the electrical potential, were solved by a finite volume method using a purposely modified CFD code and a computational grid with 643 nodes in the fluid. Emphasis was laid on the effects of increasing the Hartmann number on the complex three‐dimensional flow and current pattern.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 12 no. 6
Type: Research Article
ISSN: 0961-5539

Keywords

Article
Publication date: 1 September 2003

Hartmut Brauer, Marek Ziolkowski, Matthias Dannemann, Milko Kuilekov and Denis Alexeevski

In many industrial applications of magnetic fluid dynamics it is important to control the motion of the surface of liquids. In aluminium electrolysis cells, large surface…

Abstract

In many industrial applications of magnetic fluid dynamics it is important to control the motion of the surface of liquids. In aluminium electrolysis cells, large surface deformations of the molten aluminium are undesired, and it would be useful to have the possibility to recognize the surface deviation. This includes the problem of reconstructing a free boundary between the conducting fluids. We have investigated how the interface between two fluids of different conductivity assumed in a highly simplified model of an aluminium electrolysis cell could be reconstructed by means of external magnetic field measurements. Forward simulations of the magnetic field generated by the impressed current are done by applying the FEM software code FEMLAB. Several interface shapes which can be realized in experiments are investigated and a strategy for identifying the main interface characteristics using magnetic field measurements as an initial guess to the solution of the inverse problem is proposed.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 22 no. 3
Type: Research Article
ISSN: 0332-1649

Keywords

Article
Publication date: 6 February 2017

Biwei Tang, Zhu Zhanxia and Jianjun Luo

Aiming at obtaining a high-quality global path for a mobile robot which works in complex environments, a modified particle swarm optimization (PSO) algorithm, named…

Abstract

Purpose

Aiming at obtaining a high-quality global path for a mobile robot which works in complex environments, a modified particle swarm optimization (PSO) algorithm, named random-disturbance self-adaptive particle swarm optimization (RDSAPSO), is proposed in this paper.

Design/methodology/approach

A perturbed global updating mechanism is introduced to the global best position to avoid stagnation in RDSAPSO. Moreover, a new self-adaptive strategy is proposed to fine-tune the three control parameters in RDSAPSO to dynamically adjust the exploration and exploitation capabilities of RDSAPSO. Because the convergence of PSO is paramount and influences the quality of the generated path, this paper also analytically investigates the convergence of RDSAPSO and provides a convergence-guaranteed parameter selection principle for RDSAPSO. Finally, a RDSAPSO-based global path planning (GPP) method is developed, in which the feasibility-based rule is applied to handle the constraint of the problem.

Findings

In an attempt to validate the proposed method, it is compared against six state-of-the-art evolutionary methods under three different numerical simulations. The simulation results confirm that the proposed method is highly competitive in terms of the path optimality. Moreover, the computation time of the proposed method is comparable with those of the other compared methods.

Originality/value

Therefore, the proposed method can be considered as a vital alternative in the field of GPP.

Article
Publication date: 20 January 2023

Nathalie Darras Barquissau, Timothy L. Pett and Charlotte Fontan Sers

The purpose of this case study is to examine the hospitality industry by exploring the activities of a small, independent hotel. The hotel was experiencing disruption in recent…

534

Abstract

Purpose

The purpose of this case study is to examine the hospitality industry by exploring the activities of a small, independent hotel. The hotel was experiencing disruption in recent years due to technology, intense competition and changes in customer preferences.

Design/methodology/approach

This case study uses a qualitative methodology approach by interviewing two generations of family members that were on the brink of failure. Discussions included ways and activities in which the business was exploring that could be identified to address the loss of customers and revenues because of the digitalization of the industry.

Findings

The case findings indicate that by creating a new hybrid business model can provide a successful direction for owners facing digitization with an industry. The findings suggest creating a new hybrid business model can provide improvements in areas such as financial stability and cost reductions, attracting new customers, improved usage of assets and the ability to leverage the technology disruption in the hospitality industry.

Originality/value

This study provides a reflective examination of a small, independent hotel facing financial collapse. However, the family members were able to use the threat of new technologies to create a new opportunity by developing a new hybrid business model that other similar businesses could explore in designing.

Details

Journal of Business Strategy, vol. 45 no. 1
Type: Research Article
ISSN: 0275-6668

Keywords

Book part
Publication date: 18 November 2020

Loic Vadelorge

The development of public art in French New Towns in the 1970s and 1980s was one of the most spectacular forms of state intervention in urban policy. Along with the new…

Abstract

The development of public art in French New Towns in the 1970s and 1980s was one of the most spectacular forms of state intervention in urban policy. Along with the new architecture programmes, the hundreds of works of art that adorn the public realm of the French New Towns help to differentiate them from the grands ensembles. This public art, which was highly publicised at the time, represents a heritage intrinsically linked to the urban history of New Towns but also to the history of French cultural policies at the end of the twentieth century. Artistic and town planning innovations underlie many public art projects. Artists and town planners participated, on a city scale, in the cultural developments that sought to respond to the expectations of the May 1968 crisis. In New Towns, the role of art was not simply to provide a backdrop to beautify the city but also to contribute to the success of new urban neighbourhoods. This involved placing visual landmarks in the urban space, confronting the residents with living art (painted walls, sculpted staircases, light paths, etc.).

The appropriation of these works of art by the public and councils was far from unanimous. It was only at the beginning of the twenty-first century that a heritage reflection emerged and led to a list of works of art being drawn up, with a view to protecting them. With the disappearance of state supervision over certain New Towns (1998–2002), damaged works has become a stigma in the public realm. A policy of restoration is being therefore introduced in certain New Towns, with public art participating in the identity of councils that do not hesitate to present themselves as ‘contemporary towns’ and take on the restoration or achievement of certain works that they now consider to be their heritage.

Details

Lessons from British and French New Towns: Paradise Lost?
Type: Book
ISBN: 978-1-83909-430-9

Keywords

Abstract

Details

Secrets of Working Across Five Continents: Thriving Through the Power of Cultural Diversity
Type: Book
ISBN: 978-1-80043-011-2

Article
Publication date: 30 April 2020

Ahmad Nasseri, Sajad Jamshidi, Hassan Yazdifar, David Percy and Md Ashraful Alam

With suitable optimization criteria, hybrid models have proven to be efficient for preparing portfolios in capital markets of developed countries. This study adapts and…

Abstract

Purpose

With suitable optimization criteria, hybrid models have proven to be efficient for preparing portfolios in capital markets of developed countries. This study adapts and investigates these methods for a developing country, thus providing a novel approach to the application of banking and finance. Our specific objectives are to employ a stochastic dominance criterion to evaluate the performances of over-the-counter (OTC) companies in a developing country and to analyze them with a hybrid model involving particle swarm optimization and artificial neural networks.

Design/methodology/approach

In order to achieve these aims, the authors conduct a case study of OTC companies in Iran. Weekly and daily returns of 36 companies listed in this market are calculated for one year during 2014–2015. The hybrid model is particularly interesting, and the results of the study identify first-, second- and third-order stochastic dominances among these companies. The study’s chosen model uses the best performing combination of activation functions in our analysis, corresponding to TPT, where T represents hyperbolic tangent transfers and P represents linear transfers.

Findings

Our portfolios are based on the shares of companies ranked with respect to the stochastic dominance criterion. Considering the minimum and maximum numbers of shares to be 2 and 10 for each portfolio, an eight-share portfolio is determined to be optimal. Compared with the index of Iran OTC during the research period of this study, our selected portfolio achieves a significantly better performance. Moreover, the methods used in this analysis are shown to be as efficient as they were in the capital markets of developed countries.

Research limitations/implications

The problem of optimizing investment portfolios has to allow for correlations among returns from the financial maintenance period under consideration if an asymmetric distribution of returns exists (Babaei et al., 2015). Therefore, it is desirable to select an appropriate criterion in order to prepare an optimal portfolio and prioritize investment options. Although a back propagation technique is very popular in artificial neural (ANN) training, it is time-consuming to train a network in this way, and other methods such as particle swarm optimization (PSO) should be considered instead. In the hybrid combination of PSO and ANN, it is not the structure of a neural network that changes. Rather, the weighting method and the training technique chosen for the network are the important aspects, and these relate to PSO, so the only role ANN plays in this process is to reduce the errors.

Practical implications

The hybrid model combining ANN and PSO is seen to be considerably successful for generating optimal results and appropriate activation functions. These results are consistent with the theoretical findings of Das et al. (2013) and an application of the simple PSO in a study conducted by Pederson and Chipperfield (2010). Our research results also confirm the efficiency of stochastic dominance criteria as noted in the studies conducted by Roman et al. (2013), ANN as in a study carried out by Kristijanpoller et al. (2014) and PSO as in studies conducted by Liu et al. (2015) and Deng et al. (2012). These studies were carried out in the capital markets of developed countries, whereas the authors’ analysis relates to a developing country.

Originality/value

The authors deduce that the tools and methods whose efficiency was proven in the capital markets of developed countries also apply to, and demonstrate efficiency in, two novel applications of portfolio optimization within developing countries. The first of these is gaining familiarity with the theory and practice of these research tools and the methods that enrich financial knowledge of investors in developing countries. The second of these is the application of tools and methods identified by investors in the capital markets of developing countries, which enables optimal allocation of financial resources and growth of the markets. The authors expect that these findings will contribute to improving the economies of developing countries and thus help with economic development and facilitation of improving trends.

Details

Journal of Applied Accounting Research, vol. 21 no. 3
Type: Research Article
ISSN: 0967-5426

Keywords

Article
Publication date: 9 January 2024

Niloofar Solhjoo, Maja Krtalić and Anne Goulding

While exploring the information experience within multispecies families, the subjective nature of humans and non-human entities, living beings and non-living objects becomes…

Abstract

Purpose

While exploring the information experience within multispecies families, the subjective nature of humans and non-human entities, living beings and non-living objects becomes evident. This paper aims to reveal the underlying significance of information within socio-physical living environments shared among humans, cats and dogs as companions.

Design/methodology/approach

Gaining inspiration from the information experience approach and posthumanism, this is a phenomenological paper. Empirical material related to lived experiences of participating families were gathered through multispecies ethnography methods, followed by phenomenological reflections. The paper has been written based on excerpt-commentary-units and the inclusion of videos and images as an approach to convey the richness of the lived experiences and multiple perspectives.

Findings

Findings are organised into three main sections, each capturing lived experiences of information and its utilization from various frames. The paper shows how living beings, both human and animal, use their physical, sensual and moving bodies to acquire and convey information to and from each other. Moving beyond the living beings, the study discusses how non-living objects in the physical environment of a multispecies family also shape information. Material objects, spatial locations and even plants became sources of information for the family members. Lastly, the paper delves into the social environment of the family, where all members, human and animal, are actively shaped by information within their social interactions and companionship.

Originality/value

Considering information distributed across species and material objects in a shared, more-than-human environment, the article suggests implications for an information experience approach. It emphasizes how information shapes the in-between humans, animals and their environment, highlighting their reliance on each other for understanding and living a good shared life. There is a need for future research to explore the information experience within the internal subjective minds of members of multispecies families, bridging the gap in the understanding of these external information and their internal information processes.

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