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Article
Publication date: 12 July 2011

M.A. Latif, J.C. Chedjou and K. Kyamakya

An image contrast enhancement is one of the most important low‐level image pre‐processing tasks required by the vision‐based advanced driver assistance systems (ADAS)…

Abstract

Purpose

An image contrast enhancement is one of the most important low‐level image pre‐processing tasks required by the vision‐based advanced driver assistance systems (ADAS). This paper seeks to address this important issue keeping the real time constraints in focus, which is especially vital for the ADAS.

Design/methodology/approach

The approach is based on a paradigm of nonlinear‐coupled oscillators in image processing. Each layer of the colored images is treated as an independent grayscale image and is processed separately by the paradigm. The pixels with the lowest and the highest gray levels are chosen and their difference is enhanced to span all the gray levels in an image over the entire gray level range, i.e. [0 1]. This operation enhances the contrast in each layer and the enhanced layers are finally combined to produce a color image of a much improved quality.

Findings

The approach performs robust contrast enhancement as compared to other approaches available in the relevant literature. Generally, other approaches do need a new setting of parameters for every new image to perform its task, i.e. contrast enhancement. These approaches are not useful for real‐time applications such as ADAS. Whereas, the proposed approach presented in this paper performs contrast enhancement for different images under the same setting of parameters, hence giving rise to the robustness in the system. The unique setting of parameters is derived through a bifurcation analysis explained in the paper.

Originality/value

The proposed approach is novel in different aspects. First, the proposed paradigm comprises of coupled differential equations, and therefore, offers a continuous model as opposed to other approaches in the relevant literature. This continuity in the model is an inherent feature of the proposed approach, which could be useful in realizing real‐time image processing with an analog implemented circuit of the approach. Furthermore, a novel framework combining coupled oscillatory paradigm and cellular neural network is also possible to achieve ultra‐fast solution in image contrast enhancement.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 30 no. 4
Type: Research Article
ISSN: 0332-1649

Keywords

Article
Publication date: 12 July 2011

J.C. Chedjou and K. Kyamakya

This paper seeks to develop, propose and validate, through a series of presentable examples, a comprehensive high‐precision and ultra‐fast computing concept for solving…

Abstract

Purpose

This paper seeks to develop, propose and validate, through a series of presentable examples, a comprehensive high‐precision and ultra‐fast computing concept for solving stiff ordinary differential equations (ODEs) and partial differential equations (PDEs) with cellular neural networks (CNN).

Design/methodology/approach

The core of the concept developed in this paper is a straight‐forward scheme that we call “nonlinear adaptive optimization (NAOP)”, which is used for a precise template calculation for solving any (stiff) nonlinear ODEs through CNN processors.

Findings

One of the key contributions of this work (this is a real breakthrough) is to demonstrate the possibility of mapping/transforming different types of nonlinearities displayed by various classical and well‐known oscillators (e.g. van der Pol‐, Rayleigh‐, Duffing‐, Rössler‐, Lorenz‐, and Jerk‐ oscillators, just to name a few) unto first‐order CNN elementary cells, and thereby enabling the easy derivation of corresponding CNN‐templates. Furthermore, in case of PDEs solving, the same concept also allows a mapping unto first‐order CNN cells while considering one or even more nonlinear terms of the Taylor's series expansion generally used in the transformation of a PDEs in a set of coupled nonlinear ODEs. Therefore, the concept of this paper does significantly contribute to the consolidation of CNN as a universal and ultra‐fast solver of stiff differential equations (both ODEs and PDEs). This clearly enables a CNN‐based, real‐time, ultra‐precise, and low‐cost Computational Engineering. As proof of concept a well‐known prototype of stiff equations (van der Pol) has been considered; the corresponding precise CNN‐templates are derived to obtain precise solutions of this equation.

Originality/value

This paper contributes to the enrichment of the literature as the relevant state‐of‐the‐art does not provide a systematic and robust method to solve nonlinear ODEs and/or nonlinear PDEs using the CNN‐paradigm. Further, the “NAOP” concept developed in this paper has been proven to perform accurate and robust calculations. This concept is not based on trial‐and‐error processes as it is the case for various classes of optimization methods/tools (e.g. genetic algorithm, particle swarm, neural networks, etc.). The “NAOP” concept developed in this frame does significantly contribute to the consolidation of CNN as a universal and ultra‐fast solver of nonlinear differential equations (both ODEs and PDEs). An implantation of the concept developed is possible even on embedded digital platforms (e.g. field‐programmable gate array (FPGA), digital signal processing (DSP), graphics processing unit (GPU), etc.); this opens a broad range of applications. On‐going works (as outlook) are using NAOP for deriving precise templates for a selected set of practically interesting PDE models such as Navier Stokes, Schrödinger, Maxwell, etc.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 30 no. 4
Type: Research Article
ISSN: 0332-1649

Keywords

Article
Publication date: 19 June 2020

Zhangyuan He

Freight network planning and the application of distribution innovations are popular fields of research on sustainable urban logistics. However, considerable research on…

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Abstract

Purpose

Freight network planning and the application of distribution innovations are popular fields of research on sustainable urban logistics. However, considerable research on freight network design lacks a comprehensive consideration of the application of distribution innovations. This observation implies that sustainable urban freight research appears highly fragmented in topics of network design and distribution innovations. From the perspective of long-term planning, this situation possibly serves as a barrier to further promotion of sustainability. The objective of this paper is to analyze existing research gaps of literature to further promote the sustainability of urban logistics systems from a future perspective.

Design/methodology/approach

This paper employs a systematic literature review (SLR) method, which covers 164 papers and research works published in 2013–2018. The article corpus involved the innovative schemes of freight network design and the emerging delivery concepts in cities. Based on an analysis of articles' relevance, the most significant research contributions on both city logistics network design and exploitation of distribution innovations are detected.

Findings

This paper has found four research gaps in aspects of network design and distribution innovations. To respond to these gaps, we propose the research framework of sustainable and flexible future urban freight planning (SFFUFP) based on trends of city development, while discussing further research direction on urban freight planning.

Originality/value

The authors have found four research gaps in aspects of both urban freight network design and distribution innovations in which scholars could be encouraged to contribute. The research framework of SFFUFP can further promote sustainable urban logistics from a view of future management.

Details

International Journal of Physical Distribution & Logistics Management, vol. 50 no. 6
Type: Research Article
ISSN: 0960-0035

Keywords

Article
Publication date: 2 November 2017

Yang Gu, Qian Song, Ming Ma, Yanghuan Li and Zhimin Zhou

Aiding information is frequently adopted to calibrate the errors from inertia-generated trajectories in pedestrian positioning. However, existing calibration methods lack…

Abstract

Purpose

Aiding information is frequently adopted to calibrate the errors from inertia-generated trajectories in pedestrian positioning. However, existing calibration methods lack interior connections and unanimity, making it difficult to incorporate multiple sources of aiding information. This paper aims to propose a unanimous anchor-based trajectory calibration framework, which is expandable to encompass different types of anchor information.

Design/methodology/approach

The concept of anchors is introduced to represent different types of aiding information, which are, in essence, different constraint conditions on inertia-derived raw trajectories. The foundation of the framework is a particle filter which is implemented based on various particle weight updating strategies using diverse types of anchor information. Herein, three representative anchors are chosen to elaborate and validate the proposed framework, namely, ultra-wide-band (UWB) ranging anchors, iBeacons and the building structure-based virtual anchors.

Findings

In the simulations, with the particle reweighting strategies of the proposed framework, the positioning errors can be compensated. In the experimental test in an office building in which three anchors, including one UWB anchor, one iBeacon and one building structure-based virtual anchor are deployed; the final positioning error is decreased from 1.9 to 1.2 m; and the heading error is reduced from about 21° to 7°, respectively.

Originality/value

Herein, an anchor-based unanimous trajectory calibration framework for inertial pedestrian positioning is proposed. This framework is applicable to the schemes with different configurations of the anchors and can be expanded to adopt as much anchor information as possible.

Details

Sensor Review, vol. 37 no. 4
Type: Research Article
ISSN: 0260-2288

Keywords

Article
Publication date: 10 July 2020

Min Liu, Muzhou Hou, Juan Wang and Yangjin Cheng

This paper aims to develop a novel algorithm and apply it to solve two-dimensional linear partial differential equations (PDEs). The proposed method is based on Chebyshev…

Abstract

Purpose

This paper aims to develop a novel algorithm and apply it to solve two-dimensional linear partial differential equations (PDEs). The proposed method is based on Chebyshev neural network and extreme learning machine (ELM) called Chebyshev extreme learning machine (Ch-ELM) method.

Design/methodology/approach

The network used in the proposed method is a single hidden layer feedforward neural network. The Kronecker product of two Chebyshev polynomials is used as basis function. The weights from the input layer to the hidden layer are fixed value 1. The weights from the hidden layer to the output layer can be obtained by using ELM algorithm to solve the linear equations established by PDEs and its definite conditions.

Findings

To verify the effectiveness of the proposed method, two-dimensional linear PDEs are selected and its numerical solutions are obtained by using the proposed method. The effectiveness of the proposed method is illustrated by comparing with the analytical solutions, and its superiority is illustrated by comparing with other existing algorithms.

Originality/value

Ch-ELM algorithm for solving two-dimensional linear PDEs is proposed. The algorithm has fast execution speed and high numerical accuracy.

Details

Engineering Computations, vol. 38 no. 2
Type: Research Article
ISSN: 0264-4401

Keywords

Article
Publication date: 17 July 2020

Sengathir Janakiraman

An Improved Rank Criterion-based NLOS node Detection Mechanism (IRC-NLOS-DM) is proposed based on the benefits of a reputation model for effective localization of NLOS…

Abstract

Purpose

An Improved Rank Criterion-based NLOS node Detection Mechanism (IRC-NLOS-DM) is proposed based on the benefits of a reputation model for effective localization of NLOS nodes during the dynamic exchange of emergency messages in critical situations.

Design/methodology/approach

This proposed IRC-NLOS-DM scheme derives the benefits of a reputation model that influentially localizes the NLOS nodes under dynamic exchange of emergency messages. This proposed IRC-NLOS-DM scheme is an attempt to resolve the issues with the routing protocols that aids in warning message delivery of vehicles that are facing NLOS situations with the influence of channel contention and broadcast storm. It is developed for increasing the warning packet delivery rate with minimized overhead, delay and channel utilization.

Findings

The simulation results of the proposed IRC-NLOS-DM scheme confirmed the excellence of the proposed IRC-NLOS-DM over the existing works investigated based on the channel utilization rate, neighborhood prediction rate and emergency message forwarding rate.

Practical implications

It is proposed for reliable warning message delivery in Vehicular Ad hoc Networks (VANETs) which is referred as the specialized category of mobile ad hoc network application that influences Intelligent Transportation Systems (ITS) and wireless communications. It is proposed for implementing vehicle safety applications for constructing a least cluttered and a secure environment on the road.

Originality/value

It is contributed as a significant mechanism for facilitating reliable dissemination of emergency messages between the vehicular nodes, which is essential in the critical environment to facilitate a risk-free environment. It also aids in creating a reliable environment for accurate localization of Non-Line of Sight (NLOS) nodes that intentionally introduces the issues of broadcasting storm and channel congestion during the process of emergency message exchanges.

Details

International Journal of Intelligent Unmanned Systems, vol. 9 no. 1
Type: Research Article
ISSN: 2049-6427

Keywords

Article
Publication date: 22 July 2021

Meysam Soltaninejad, Amir Faraji and Esmatullah Noorzai

The purpose of this study is to introduce and evaluate the effect of critical success factors (CSF) in rescue operations in burning buildings by calculating the partial…

Abstract

Purpose

The purpose of this study is to introduce and evaluate the effect of critical success factors (CSF) in rescue operations in burning buildings by calculating the partial least squares structural equation modeling of PLS-SEM.

Design/methodology/approach

To do this, success criteria (SC) and CSF in the literature, which are related to the topic, articles, standards and relevant books, will be identified and then evaluated through the extended PLS-SEM model.

Findings

The results show that technological factors, awareness, resources and safety play an effective role in successful performance management in fire accidents.

Research limitations/implications

Appropriate use of these factors will promote incident management and decrease casualties and financial loss in the event of accidents.

Originality/value

Fire-fighting is of great importance, especially in tall and complex buildings. In recent years, extended studies have been carried out regarding fire accident management in terms of CSFs in the category of rescue and firefighting. However, attention has not been paid to the relation and severity of impact between SC and CSF by researchers in addition to the identification of the most important criteria during rescue operations.

Details

Facilities , vol. 39 no. 13/14
Type: Research Article
ISSN: 0263-2772

Keywords

Article
Publication date: 3 September 2020

Nishadi Egodage, Fathima Nishara Abdeen and Pournima Sridarran

The incidence of disability is increasing globally over the past decades. Despite the increased proportion of disabled individuals, established fire emergency evacuation…

Abstract

Purpose

The incidence of disability is increasing globally over the past decades. Despite the increased proportion of disabled individuals, established fire emergency evacuation procedures for disabled in high-rise buildings are lacking attention. Hence, this paper aims to focus on investigating fire emergency evacuation procedures for differently-abled people in high-rise buildings.

Design/methodology/approach

To address the gap, the case study strategy under the qualitative research approach was deployed by focussing 10 high-rise buildings. Data collected through semi-structured interviews and document reviews were analysed using content analysis.

Findings

The study findings revealed that even though a fire disaster is a major area to be considered, there is a noticeable gap in legal requirements related to differently-abled fire evacuation in Sri Lanka compared to the global context. Moreover, it was identified that importance given to differently enabled fire evacuations procedures varied based on the type of high-rise facilities in which hospitals and hotels provided more importance compared to office buildings, apartments and shopping complexes. Further, the study has highlighted the main gaps in the evacuation procedures and improvements required. Lack of imposed regulations for disabled evacuation was identified as a major barrier hindering the development of effective fire evacuation procedures for disabled, which creates a cascading effect. Further, the consideration given to legal, organisational, individual and technological factors would assist in straightening the identified issues.

Originality/value

This research provides a clear insight into the necessity of focussing at disabled individuals when developing fire emergency procedures. Most importantly, this study had exposed the current gaps in fire emergency evacuation procedures for the disabled community. Understanding these gaps is of high value for industry practitioners to ensure disabled safety during a fire emergency.

Details

Journal of Facilities Management , vol. 18 no. 5
Type: Research Article
ISSN: 1472-5967

Keywords

Article
Publication date: 7 September 2015

Peter Cariani

The purpose of this paper is to outline an integrative, high-level, neurocomputational theory of brain function based on temporal codes, neural timing nets, and active…

Abstract

Purpose

The purpose of this paper is to outline an integrative, high-level, neurocomputational theory of brain function based on temporal codes, neural timing nets, and active regeneration of temporal patterns of spikes within recurrent neural circuits that provides a time-domain alternative to connectionist approaches.

Design/methodology/approach

This conceptual-theoretical paper draws from cybernetics, theoretical biology, neurophysiology, integrative and computational neuroscience, psychology, and consciousness studies.

Findings

The high-level functional organization of the brain involves adaptive cybernetic, goal-seeking, switching, and steering mechanisms embedded in percept-action-environment loops. The cerebral cortex is conceived as a network of reciprocally connected, re-entrant loops within which circulate neuronal signals that build up, decay, and/or actively regenerate. The basic signals themselves are temporal patterns of spikes (temporal codes), held in the spike correlation mass-statistics of both local and global neuronal ensembles. Complex temporal codes afford multidimensional vectorial representations, multiplexing of multiple signals in spike trains, broadcast strategies of neural coordination, and mutually reinforcing, autopoiesis-like dynamics. Our working hypothesis is that complex temporal codes form multidimensional vectorial representations that interact with each other such that a few basic processes and operations may account for the vast majority of both low- and high-level neural informational functions. These operational primitives include mutual amplification/inhibition of temporal pattern vectors, extraction of common signal dimensions, formation of neural assemblies that generate new temporal pattern primitive “tags” from meaningful, recurring combinations of features (perceptual symbols), active regeneration of temporal patterns, content-addressable temporal pattern memory, and long-term storage and retrieval of temporal patterns via a common synaptic and/or molecular mechanism. The result is a relatively simplified, signal-centric view of the brain that utilizes universal coding schemes and pattern-resonance processing operations. In neurophenomenal terms, waking consciousness requires regeneration and build up of temporal pattern signals in global loops, whose form determines the contents of conscious experience at any moment.

Practical implications

Understanding how brains work as informational engines has manifold long-reaching practical implications for design of autonomous, adaptive robotic systems. By proposing how new concepts might arise in brains, the theory bears potential implications for constructivist theories of mind, i.e. how observer-actors interacting with one another can self-organize and complexify.

Originality/value

The theory is highly original and heterodox in its neural coding and neurocomputational assumptions. By providing a possible alternative to standard connectionist theory of brain function, it expands the scope of thinking about how brains might work as informational systems.

Details

Kybernetes, vol. 44 no. 8/9
Type: Research Article
ISSN: 0368-492X

Keywords

Article
Publication date: 3 May 2013

Nguyen Xuan Quyen, Vu Van Yem, Thang Manh Hoang and Kyandoghere Kyamakya

This paper presents and investigates a method named M×N‐ary chaotic pulse‐width‐position modulation (CPWPM) which is based on the combination of M‐ary chaotic…

Abstract

Purpose

This paper presents and investigates a method named M×N‐ary chaotic pulse‐width‐position modulation (CPWPM) which is based on the combination of M‐ary chaotic pulse‐position modulation (CPPM) and N‐ary chaotic pulse‐width modulation (CPWM) in order to provide a better performance in noise‐affected environments as well as improve significantly bit rate.

Design/methodology/approach

Analysis of schemes for modulator and demodulator are presented in detail through describing the schemes of the individual methods and their combination. Theoretical evaluation of bit‐error rate (BER) performance in presence of additive white Gaussian noise (AWGN) is provided. Chaotic behavior with tent map in variation of modulation parameters is also investigated. In order to verify the theoretical analyses, numerical simulations are carried out and their results are reported.

Findings

Both evaluation and simulation results show that when the number of symbols increases, the bit rate is improved significantly but the BER performance is just slightly worse. This makes M×N‐ary CPWPM become an effective method for chaos‐based digital communication.

Originality/value

Although CPPM, CPWM and M‐ary modulation methods have been described in the literature separately, their combination is presented and investigated for the first time in this paper.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 32 no. 3
Type: Research Article
ISSN: 0332-1649

Keywords

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