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1.Special issue on computational intelligence for social media data mining and knowledge discovery

Author:Li, Y;Shyamasundar, RK;Wang, XH

Source:COMPUTATIONAL INTELLIGENCE,2021,Vol.37

2.Identifying the influential spreaders in multilayer interactions of online social networks

Author:Al-Garadi, MA;Varathan, KD;Ravana, SD;Ahmed, E;Chang, V

Source:JOURNAL OF INTELLIGENT & FUZZY SYSTEMS,2016,Vol.31

Abstract:Online social networks (OSNs) portray a multi-layer of interactions through which users become a friend, information is propagated, ideas are shared, and interaction is constructed within an OSN. Identifying the most influential spreaders in a network is a significant step towards improving the use of existing resources to speed up the spread of information for application such as viral marketing or hindering the spread of information for application like virus blocking and rumor restraint. Users communications facilitated by OSNs could confront the temporal and spatial limitations of traditional communications in an exceptional way, thereby presenting new layers of social interactions, which coincides and collaborates with current interaction layers to redefine the multiplex OSN. In this paper, the effects of different topological network structure on influential spreaders identification are investigated. The results analysis concluded that improving the accuracy of influential spreaders identification in OSNs is not only by improving identification algorithms but also by developing a network topology that represents the information diffusion well. Moreover, in this paper a topological representation for an OSN is proposed which takes into accounts both multilayers interactions as well as overlaying links as weight. The measurement results are found to be more reliable when the identification algorithms are applied to proposed topological representation compared when these algorithms are applied to single layer representations.

3.A comparative study of models for shear strength of reinforced concrete T-beams

Author:Liu, J;Gao, ZY

Source:STRUCTURES,2022,Vol.35

Abstract:Reinforced concrete T-beams are widely used in bridges where beams are cast integrally with deck sections to either side at the beam tops. Although it has been recognized by numerous experimental studies that flanges may have a significant contribution to the shear strength of reinforced concrete T-beams, they are neglected in most of the design codes. In this paper, the load paths to transfer shear force in T-beams are firstly investigated with the help of existing experimental tests. Compared with rectangular beams, an additional load path diverts the diagonal compression from the loading point and the end support, and it carries a portion of the shear force through the flange to the end support. In order to find a relatively reliable model to predict the shear strength of T-beams, a comparative study is carried out among five representative models selected from the literature by using a database with 233 reported T-beam tests. Parametric studies with individual test series are also performed for a detailed evaluation of the five models. It is found that a model proposed by Cladera et al. (i.e., Model [3] is one of the models producing the least scattered predictions. The average shear strength experimental-to-predicted ratio V-exp/V-pred is 1.06 with the coefficient of variation (COV) of 19.6%%. At the same time, it is shown that Model [3] exhibits uniform results across the entire range of experimental data without obvious bias. At the same time, Model [3] is one of the models requiring the least computational effort but with the largest range of applicability.

4.Minimize Reactive Power Losses of Dual Active Bridge Converters using Unified Dual Phase Shift Control

Author:Wen, HQ;Su, B

Source:JOURNAL OF ELECTRICAL ENGINEERING & TECHNOLOGY,2017,Vol.12

Abstract:This paper proposed an unified dual-phase-shift (UDPS) control for dual active bridge (DAB) converters in order to improve efficiency for a wide output power range. Different operating modes of UDPS are characterized with respect to the reactive current distribution. The proposed UDPS has the same output power capability with conventional phase-shift (CPS) method. Furthermore, its implementation is simple since only the change of the leading phase-shift direction is required for different operating power range. The proposed UDPS control can minimize both the inductor rms current and the circulating reactive current for various voltage conversion ratios and load conditions. The optimal phase-shift pairs for two bridges of DAB converter are derived with respect to the comprehensive reactive power loss model, including the reactive components delivered from the load and back to the source. Simulation and experimental results are illustrated and explained with details. The effectiveness of the proposed method is verified in terms of reactive power losses minimization and efficiency improvement.

5.Quantitative and rapid detection of microcystin-LR using time-resolved fluorescence immunochromatographic assay based on europium nanospheres

Author:Zhang, Y;Ding, XL;Guo, MM;Han, TT;Huang, ZJ;Shang, HT;Huang, B

Source:ANALYTICAL METHODS,2017,Vol.9

Abstract:In the present study, a novel time-resolved fluorescence immunochromatographic assay was established for the rapid quantitative detection of microcystin-leucine arginine (MC-LR). In this method, the europium nanoshpere labelled with anti-MC-LR antibodies was used as the luminescent tracer, dissolved in the running buffer and then added with the sample solution on the pad. MC-LR-BSA and goat anti-mouse antibody were dispensed on the nitrocellulose membrane for the test and the control line, respectively. The optimal parameters were 0.05 g L-1 MC-LR-BSA, 1 : 100 colloidal europium-antibody conjugate, and 10 min reaction time. The linear working range for MC-LR was 0.1-5 mu g L-1 with an IC50 of 0.78 mu g L-1 and a sensitivity of 0.035 mu g L-1. The low cross-reactivity was observed with MC-YR and MC-LF. The assay accuracy was confirmed by the HPLC method with a correlation coefficient of 0.99. When the variable coefficients were 4.4%% and 5.4%%, the average recoveries of tap and lake water were 94.6%% and 102.8%%, respectively. The time-resolved fluorescence immunochromatographic assay provides a sensitive, simple, and speedy performance for MC-LR quantitative determination and has a potential use for water sample screening.

6.On the theoretical distribution of the wind farm power when there is a correlation between wind speed and wind turbine availability

Author:Kan, C;Devrim, Y;Eryilmaz, S

Source:RELIABILITY ENGINEERING & SYSTEM SAFETY,2020,Vol.203

Abstract:It is important to elicit information about the potential power output of a wind turbine and a wind farm consisting of specified number of wind turbines before installation of the turbines. Such information can be used to estimate the potential power output of the wind farm which will be built in a specific region. The output power of a wind turbine is affected by two factors: wind speed and turbine availability. As shown in the literature, the correlation between wind speed and wind turbine availability has an impact on the output of a wind farm. Thus, the probability distribution of the power produced by the farm depending on the wind speed distribution and turbine availability can be effectively used for planning and risk management. In this paper, the theoretical distribution of the wind farm power is derived by considering the dependence between turbine availability and the wind speed. The theoretical results are illustrated for real wind turbine reliability and wind speed data.

7.2,2-Dicyanovinyl-end-capped oligothiophenes as electron acceptor in solution processed bulk-heterojunction organic solar cells

Author:Wu, J;Ma, Y;Wu, N;Lin, Y;Lin, J;Wang, L;Ma, CQ

Source:ORGANIC ELECTRONICS,2015,Vol.23

Abstract:Three 2,2-dicyanovinyl (DCV) end-capped A-pi-D-pi-A type oligothiophenes (DCV-OTs) containing dithieno[3,2-b: 2',3'-d] silole (DTSi), cyclopenta[1,2-b: 3,4-b'] dithiophene (DTCP) or dithieno[3,2-b: 2',3'-d] pyrrole (DTPy) unit as the central donor part, mono-thiophene as the pi-conjugation bridge were synthesized. The absorption spectroscopies, cyclic voltammetry of these compounds were characterized. Results showed that all these compounds have intensive absorption band over 500-680 nm with a LUMO energy level around -3.80 eV, which is slightly higher than that of [6,6] phenyl-C-61-butyric acid methyl ester (PC61BM, E-LUMO = -4.01 eV), but lower than that of poly(3-hexylthiophene) (P3HT, ELUMO = -2.91 eV). Solution processed bulk heterojunction "all-thiophene'' solar cells using P3HT as electron donor and the above mentioned oligothiophenes as electron acceptor were fabricated and tested. The highest power conversion efficiency (PCE) of 1.31%% was achieved for DTSi-cored compound DTSi(THDCV) 2, whereas PTB7: DTSi(THDCV) 2 based device showed slightly higher PCE of 1.56%%. Electron mobilities of these three compounds were measured to be around 10 (5) cm(2) V (1) s (1) by space charge limited current method, which is much lower than that of PC61BM, and was considered as one of the reason for the low photovoltaic performance. (C) 2015 Elsevier B.V. All rights reserved.

8.Clinical Validity and Reliability of the Malay Language Translations of Gastroesophageal Reflux Disease Questionnaire and Quality of Life in Reflux and Dyspepsia Questionnaire in a Primary Care Setting

Author:Vadivelu, S;Ma, ZF;Ong, EW;Hassan, N;Hassan, NFHN;Aziz, SHSA;Kueh, YC;Lee, YY

Source:DIGESTIVE DISEASES,2019,Vol.37

Abstract:Background: Gastroesophageal Reflux Disease Questionnaire (GERDQ) and Quality of Life in Reflux and Dyspepsia Questionnaire (QOLRAD) are reliable tools for evaluation of GERD. Aim: We aimed to test validity and reliability of Malay language translations of GERDQ and QOLRAD in a primary care setting. Methods: The questionnaires were first translated into the Malay language (GERDQ-M and QOLRAD-M). Patients from primary care clinics with suspected GERD were recruited to complete GERDQ-M, QOLRAD-M, and Malay-translated 36-item short-form health survey (SF-36 or SF36-M), and underwent endoscopy and 24-h pH-impedance test. Results: A total of 104 (mean age 47.1 years, women 51.9%%) participants were enrolled. The sensitivity and specificity for GERDQ-M cut-off score >= 8 were 90.2 and 77.4%%, respectively. Based on this cut-off score, 54.7%% had a high probability of GERD diagnosis. GERD-M score >= 8 vs. <8 was associated with erosive esophagitis (p < 0.001), hiatus hernia (p = 0.03), greater DeMeester score (p = 0.001), and Zerbib scores for acid refluxes (p < 0.001) but not non-acid refluxes (p = 0.1). Mean total scores of QOLRAD-M and SF-36-M were correlated (r = 0.74, p < 0.001). GERDQ-M = 8, erosive esophagitis, and DeMeester >= 14.72 were associated with impaired QOLRAD-M in all domains (all p < 0.02) but this was not seen with SF-36. Conclusions: GERDQ-M and QOLRAD-M are valid and reliable tools applicable in a primary care setting. (C) 2018 S. Karger AG, Basel

9.Experimental and Numerical Study on Impact of Double Layer Vegetation in Open Channel Flows

Author:Rahimi, HR;Tang, X;Singh, P

Source:JOURNAL OF HYDROLOGIC ENGINEERING,2020,Vol.25

Abstract:This paper studies the effects of different types and configurations of double layer vegetation on the flow of open channels. The vegetation is simulated through cylindrical dowels with a diameter of 6.35 mm and heights of 10 and 20 cm, which represent short and tall dowels, respectively. Profiles for instantaneous velocities were obtained by acoustic Doppler velocimetry (ADV) at different locations around vegetation with multiple staggered and linear formations. The experiment covers a wide range of sparse to dense vegetation configurations. Furthermore, different flow depths were selected to simulate fully submerged cases for short vegetation and to capture the inflection of velocity over the mixing region between short and tall dowels. The results reveal that the velocity profile is mostly uniform at the depth of short vegetation in different configurations with various densities. The velocity starts to increase in the region near the top edge of short vegetation, followed by a significant increase through the height of tall vegetation to the free surface. Generally, the flow velocity behind the vegetation layer is significantly smaller than that in free regions adjacent to short and tall vegetation. The overall idea of the present study was to simulate the same sets of vegetation configurations using a K-epsilon model with mesh sensitivity analysis to capture inflections over the short vegetation region. The experimental investigations with a numerical study were explored for double layer vegetation, which was corroborated and found to have good agreement for different vegetation configurations. (C) 2019 American Society of Civil Engineers.

10.Key management and key distribution for secure group communication in mobile and cloud network

Author:Vijayakumar, P;Chang, V;Deborah, LJ;Kshatriya, BSR

Source:FUTURE GENERATION COMPUTER SYSTEMS-THE INTERNATIONAL JOURNAL OF ESCIENCE,2018,Vol.84

Abstract:With the computing systems becoming more and more pervasive and ubiquitous due to the invention of cloud computing and mobile phone based applications, secure data transmission is the pressing need for a real time perspective of the technologies. Examples of the need for secure key management and distribution environments include secure transmission of health related SMS, telecare medicine provisioning for critical applications such as heart disorders, secure agriculture monitoring, data transmission in surveillance scenarios, secure military networks, etc. In the context of key exchange for secure group communication, the computational complexities need to be addressed in particular due to the advent of resource constrained mobile phones, sensors and other embedded devices. This special issue introduces some of the novel approaches for enabling secure group communication in the contexts related to cloud and mobile computing. (C) 2018 Published by Elsevier B.V.

11.Dual algorithm for truncated fractional variation based image denoising

Author:Liang, HX;Zhang, JL

Source:INTERNATIONAL JOURNAL OF COMPUTER MATHEMATICS,2020,Vol.97

Abstract:Fractional-order derivative is attracting more and more attention of researchers in image processing because of its better property in restoring more texture than the total variation. To improve the performance of fractional-order variation model in image restoration, a truncated fractional-order variation model was proposed in Chan and Liang [Truncated fractional-order variation model for image restoration, J. Oper. Res. Soc. China]. In this paper, we propose a dual approach to solve this truncated fractional-order variation model on noise removal. The proposed algorithm is based on the dual approach proposed by Chambolle [An algorithm for total variation minimisation and applications, J. Math Imaging Vis. 20 (2004), pp. 89-97]. Conversely, the Chambolle's dual approach can be treated as a special case of the proposed algorithm with fractional order . The work of this paper modifies the result in Zhang et al. [Adaptive fractional-order multi-scale method for image denoising, J. Math. Imaging Vis. 43(1) (2012), pp. 39-49. Springer Netherlands 0924-9907, Computer Science, pp. 1-11, 2011], where the convergence is not analysed. Based on the truncation, the convergence of the proposed dual method can be analysed and the convergence criteria can be provided. In addition, the accuracy of the reconstruction is improved after the truncation is taken.

12.Dopamine Surface Modification of Trititanate Nanotubes: Proposed In-Situ Structure Models.

Author:Liu, Ruochen; Fu, Xuejian; Wang, Congyi; Dawson, Graham

Source:Chemistry (Weinheim an der Bergstrasse, Germany),2016,Vol.22

Abstract:Two models for self-assembled dopamine on the surface of trititanate nanotubes are proposed: individual monomer units linked by π-π stacking of the aromatic regions and mono-attached units interacting through hydrogen bonds. This was investigated with solid state NMR spectroscopy studies and powder X-ray diffraction.

13.An atomic finite element model for biodegradable polymers. Part 1. Formulation of the finite elements

Author:Gleadall, A;Pan, JZ;Ding, LF;Kruft, MA;Curco, D

Source:JOURNAL OF THE MECHANICAL BEHAVIOR OF BIOMEDICAL MATERIALS,2015,Vol.51

Abstract:Molecular dynamics (MD) simulations are widely used to analyse materials at the atomic scale. However, MD has high computational demands, which may inhibit its use for simulations of structures involving large numbers of atoms such as amorphous polymer structures. An atomic-scale finite element method (AFEM) is presented in this study with significantly lower computational demands than MD. Due to the reduced computational demands, AFEM is suitable for the analysis of Young's modulus of amorphous polymer structures. This is of particular interest when studying the degradation of bioresorbable polymers, which is the topic of an accompanying paper. AFEM is derived from the inter-atomic potential energy functions of an MD force field. The nonlinear MD functions were adapted to enable static linear analysis. Finite element formulations were derived to represent interatomic potential energy functions between two, three and four atoms. Validation of the AFEM was conducted through its application to atomic structures for crystalline and amorphous poly(lactide). (C) 2015 Elsevier Ltd. All rights reserved.

14.Critically paintable, choosable or colorable graphs

Author:Riasat, A;Schauz, U

Source:DISCRETE MATHEMATICS,2012,Vol.312

Abstract:We extend results about critically k-colorable graphs to choosability and paintability (list colorability and on-line list colorability). Using a strong version of Brooks' Theorem, we generalize Gallai's Theorem about the structure of the low-degree subgraph of critically k-colorable graphs, and introduce a more adequate lowest-degree subgraph. We prove lower bounds for the edge density of critical graphs, and generalize Heawood's Map-Coloring Theorem about graphs on higher surfaces to paintability. We also show that on a fixed given surface, there are only finitely many critically k-paintable/k-choosable/k-colorable graphs, if k >= 6. In this situation, we can determine in polynomial time k-paintability, k-choosability and k-colorability, by giving a polynomial time coloring strategy for "Mrs. Correct". Our generalizations of k-choosability theorems also concern the treatment of non-constant list sizes (non-constant k). Finally, we use a Ramsey-type lemma to deduce all 2-paintable, 2-choosable, critically 3-paintable and critically 3-choosable graphs, with respect to vertex deletion and to edge deletion. (C) 2012 Elsevier B.V. All rights reserved.

15.Three-Dimensional Local Energy-Based Shape Histogram (3D-LESH): A Novel Feature Extraction Technique

Author:Wajid, SK;Hussain, A;Huang, KZ

Source:EXPERT SYSTEMS WITH APPLICATIONS,2018,Vol.112

Abstract:In this paper, we present a novel feature extraction technique, termed Three-Dimensional Local Energy-Based Shape Histogram (3D-LESH), and exploit it to detect breast cancer in volumetric medical images. The technique is incorporated as part of an intelligent expert system that can aid medical practitioners making diagnostic decisions. Analysis of volumetric images, slice by slice, is cumbersome and inefficient. Hence, 3D-LESH is designed to compute a histogram-based feature set from a local energy map, calculated using a phase congruency (PC) measure of volumetric Magnetic Resonance Imaging (MRI) scans in 3D space. 3D-LESH features are invariant to contrast intensity variations within different slices of the MRI scan and are thus suitable for medical image analysis. The contribution of this article is manifold. First, we formulate a novel 3D-LESH feature extraction technique for 3D medical images to analyse volumetric images. Further, the proposed 3D-LESH algorithmic, for the first time, applied to medical MRI images. The final contribution is the design of an intelligent clinical decision support system (CDSS) as a multi-stage approach, combining novel 3D-LESH feature extraction with machine learning classifiers, to detect cancer from breast MRI scans. The proposed system applies contrast-limited adaptive histogram equalisation (CLAHE) to the MRI images before extracting 3D-LESH features. Furthermore, a selected subset of these features is fed into a machine-learning classifier, namely, a support vector machine (SVM), an extreme learning machine (ELM) or an echo state network (ESN) classifier, to detect abnormalities and distinguish between different stages of abnormality. We demonstrate the performance of the proposed technique by its application to benchmark breast cancer MRI images. The results indicate high-performance accuracy of the proposed system (98%%+/- 0.0050, with an area under a receiver operating charactertistic curve value of 0.9900 +/- 0.0050) with multiple classifiers. When compared with the state-of-the-art wavelet-based feature extraction technique, statistical analysis provides conclusive evidence of the significance of our proposed 3D-LESH algorithm. (C) 2017 The Authors. Published by Elsevier Ltd.

16.Moving shadow detection via binocular vision and colour clustering

Author:Lu, L;Xu, M;Smith, JS;Yan, YY

Source:IET COMPUTER VISION,2020,Vol.14

Abstract:A pedestrian segmentation algorithm in the presence of cast shadows is presented in this study. The novelty of this algorithm lies in the fusion of multi-view and multi-plane homographic projections of foregrounds and the use of the fused data to guide colour clustering. This brings about an advantage over the existing binocular algorithms in that it can remove cast shadows while keeping pedestrians' body parts, which occlude shadows. Phantom detection, which is inherent with the binocular method, is also investigated. Experimental results with real-world videos have demonstrated the efficiency of this algorithm.

17.An Improved Brain Storm Optimization with Differential Evolution Strategy for Applications of ANNs

Author:Cao, ZJ;Hei, XH;Wang, L;Shi, YH;Rong, XF

Source:MATHEMATICAL PROBLEMS IN ENGINEERING,2015,Vol.2015

Abstract:Brain Storm Optimization (BSO) algorithm is a swarm intelligence algorithm inspired by human being's behavior of brainstorming. The performance of BSO is maintained by the creating process of ideas, but when it cannot find a better solution for some successive iterations, the result will be so inefficient that the population might be trapped into local optima. In this paper, we propose an improved BSO algorithm with differential evolution strategy and new step size method. Firstly, differential evolution strategy is incorporated into the creating operator of ideas to allow BSO jump out of stagnation, owing to its strong searching ability. Secondly, we introduce a new step size control method that can better balance exploration and exploitation at different searching generations. Finally, the proposed algorithm is first tested on 14 benchmark functions of CEC 2005 and then is applied to train artificial neural networks. Comparative experimental results illustrate that the proposed algorithm performs significantly better than the original BSO.

18.Material Characterization for Sustainable Concrete Paving Blocks

Author:Wang, XY;Chin, CS;Xia, J

Source:APPLIED SCIENCES-BASEL,2019,Vol.9

Abstract:Recycled aggregates have been widely studied and used in concrete products nowadays. There are still many waste materials that can be used as recycled aggregates other than crushed concrete particles. This paper aims to study the property variations of sustainable concrete paving block incorporating different contents of construction wastes. Five different types of waste materials were used in this project, including: recycled concrete coarse aggregate (RCCA), recycled concrete fine aggregate (RCFA), crushed glass (CG), crumb rubber (CB), and ground granulated blast furnace slag (GGBS). According to the test results of the properties of blocks mixed with different levels of wastes materials, it is concluded that adding both RCCA and RCFA in the block can decrease its strength and increase the water absorption. The suggested replacement levels for RCCA and RCFA are 60%% and 20%%, respectively. Mixing crushed glass in the concrete paving blocks as a type of coarse aggregates can improve the blocks' strength and decrease the blocks' water absorption. Addition of crumb rubber causes a significant deterioration of blocks' properties except for its slip resistance.

19.THE ZERO LEVEL SET FOR A CERTAIN WEAK SOLUTION, WITH APPLICATIONS TO THE BELLMAN EQUATIONS

Author:Andersson, J;Mikayelyan, H

Source:TRANSACTIONS OF THE AMERICAN MATHEMATICAL SOCIETY,2013,Vol.365

Abstract:We will prove a partial regularity result for the zero level set of weak solutions to div(B del u) = 0, where B = B(u) = I + (A - I)chi({u<0}), where I is the identity matrix and the eigenvalues of A are strictly positive and bounded. We will apply this to describe the regularity of solutions to the Bellman equations.

20.Macroinvertebrate drift-benthos trends in a regulated river

Author:Tonkin, JD;Death, RG

Source:FUNDAMENTAL AND APPLIED LIMNOLOGY,2013,Vol.182

Abstract:Downstream drift plays a fundamental role in the spatial distribution and community structure of lotic macroinvertebrates. We sampled both benthic and drifting macroinvertebrates at 15 sites, in three sections of river with varying flow alteration along the Tongariro River, New Zealand. Our objectives were to examine whether (i) benthic and drift density were linearly related throughout the river, (ii) the presence of dams affected the propensity of macroinvertebrates to drift, and (iii) drift propensity was related to benthic periphyton biomass or natural longitudinal patterns down the river. More taxa were collected from the drift than the benthos, although drift and benthic samples were generally taxonomically similar, despite some structural differences. Nonetheless, differences were evident between the major groups when assessing density and relative abundance links between the benthos and drift. The presence of dams did not affect the propensity of macroinvertebrates to drift on the whole, nor was propensity affected by periphyton biomass or distance from source. These results suggest that although altered periphyton biomass in downstream sections in the Tongariro River is altering the composition of benthic and drifting macroinvertebrates, drift propensity is unaffected. However, some deviations from linear relationships between benthic and drift density are evident suggesting these links may be taxon specific.
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