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Petroleum 2020年第4期6卷 329-339页

作者： veronica k.h.chan Christine W.chan Energy Informatics Laboratory Faculty of Engineering and Applied ScienceUniversity of ReginaReginaSK S4S 0A2Canada

In the quest for interpretable models,two versions of a neural network rule extraction algorithm were proposed and *** two algorithms are called the Piece-Wise Linear Artificial Neural Network(PWL-ANN)and enhanced Piece-Wise Linear Artificial Neural Network(enhanced PWL-ANN)*** PWL-ANN algorithm is a decomposition artificial neural network(ANN)rule extraction algorithm,and the enhanced PWL-ANN algorithm improves upon the PWL-ANN algorithm and extracts multiple linear regression equations from a trained ANN model by approximating the hidden sigmoid activation functions using N-piece linear *** doing so,the algorithm provides interpretable models from the originally trained opaque ANN models.A detailed application case study illustrates how the generated enhanced-PWL-ANN models can provide understandable IF-ThEN rules about a problem *** of the results generated by the two versions of the PWL-ANN algorithm showed that in comparison to the PWL-ANN models,the enhanced-PWL-ANN models support improved fidelities to the originally trained ANN *** results also showed that more concise rule sets could be generated using the enhanced-PWL-ANN *** a more simplified set of rules is desired,the enhanced-PWL-ANN algorithm can be combined with the decision tree *** application of the algorithms to domains related to petroleum engineering can help enhance understanding of the problems.

关键词： Artificial neural networks Rule extraction Regression problem Algorithm design

A review on human influenza A h5N1 infections in hong kong

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Science China(Life Sciences) 2009年第5期52卷 412-418页

作者： chan Paul k S Department of Microbiology The Chinese University of Hong Kong1/F Clinical Sciences BuildingPrince of Wales HospitalShatinNew TerritoriesHong Kong Special Administrative Region China

Avian influenza A h5N1 remains the most threatening virus that may cause another devastating pandemic in the foreseeable future. In 1997, hong kong was the first place to detect human infections due to this virus originated from birds. The experience and lessons learnt provide important information for controlling further outbreaks caused by avian influenza viruses.

关键词： Avian influenza h5N1 hong kong pandemic

Evaluation of particle packing models by comparing with published test results

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Particuology 2014年第5期12卷 108-115页

作者： k.W.chan A.k.h.kwan Department of Civil Engineering The University of Hong Kong

The existing particle packing density models each with two or more parameters accounting for certain particle interactions （the loosening effect parameter, wall effect parameter, wedging effect parameter, and compaction index, denoted by a, b, c, and k, respectively） may be classified into the 2-parameter model （with a and b incorporated）, the compressible model （with a, b, and 1（incorporated）, and the 3- parameter model （with a, b, and c incorporated）. This paper evaluates these models by comparing their respective packing density predictions with the test results published in the literature. It was found that their accuracy varies with both the size ratio and volumetric fractions of the binary mix. In general, when the size ratio is larger than 0.65, all the packing models are sufficiently accurate. however, when the size ratio is smaller than 0.65, some of them become inaccurate and the errors tend to be larger at around the volumetric fractions giving maximum packing density. Relatively, the 3-parameter model is the most accurate and widely applicable.

关键词： Packing density Particle packing models Particle interactions

Theoretical and experimental studies of heat transfer with moving phase-change interface in freezing and thawing of porous potting soil

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第1期10卷 1-6页

作者： Michael k.h.LEUNG kit-ying chan Department of Mechanical Engineering the University of Hong Kong

Soil in a cold region is subject to frequent freezing and thawing *** frozen for a prolonged period may cause adverse freeze damage to the plants due to cell dehydration or root cell *** is important to understand the detailed heat transfer behaviors of the freezing and thawing processes to prevent freeze damage,and to devise proper mitigation measures for effective pot planting in cold regions.A theoretical model was developed to analyze the transient moving phase-change interface heat transfer in the freezing and thawing of porous potting *** theoretical derivation is based on the assumption that the soil freezes completely at a single *** poromechanic effects on heat transfer behavior were *** spatial domain of the problem was simplified to a 1D spherical coordinate system with variation in the radial ***'s function was applied to solve for the time-dependent body *** were conducted for validation of the theoretical *** agreement between the theoretical predictions and experimental measurements was *** theoretical model developed can be easily used to determine the sensitivity of various parameters in the freezing/thawing processes,e.g.,thermal properties of soil,ambient temperature,and planting pot size.

关键词： Porous soil Freezing Thawing Moving phase-change interface Theoretical model

Neuroinflammation as a therapeutic target in huntington's disease

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Neural Regeneration Research 2025年第3期20卷 817-818页

作者： Andrea kwakowsky Thulani h.Palpagama Center for Brain Research and Department of Anatomy and Medical Imaging Faculty of Medical and Health SciencesUniversity of AucklandAucklandNew Zealand Pharmacology and Therapeutics School of MedicineGalway Neuroscience CentreUniversity of GalwayGalwayIreland

In 1872, George huntington presented his essay “On Chorea” to the Meigs and Mason Academy of Medicine and, in doing so, detailed a disease that would later bear his name. huntington's disease(hD) is a genetic, neurodegenerative disease that manifests as the loss of motor control,cognitive impairment,and mood and psychiatric changes in paents.

关键词： huntington inflammation Medicine

Glial response in the midcingulate cortex in huntington’s disease

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Neural Regeneration Research 2025年第1期20卷 207-208页

作者： Thulani h.Palpagama Andrea kwakowsky Center for Brain Research and Department of Anatomy and Medical Imaging Faculty of Medical and Health SciencesUniversity of AucklandAucklandNew Zealand Pharmacology and Therapeutics School of MedicineGalway Neuroscience CenterUniversity of GalwayGalwayIreland

huntington’s disease(hD)is a genetic disease characterized by the progressive degeneration of the striatum and *** can present with a variety of symptoms that can broadly be classified into motor symptoms,inclusive of choreatic movements and rigidity,mood and psychiatric symptoms,such as depression and apathy,and cognitive symptoms,such as cognitive *** causal mutation underlying hD results from an expansion of a CAG repeat sequence on the IT15 gene,resulting in the formation and accumulation of a mutant huntingtin protein.

关键词： huntington degeneration cortex

Formation of TiN Grid on NiTi by Laser Gas Nitriding for Improving Wear Resistance in hanks' Solution

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Journal of Materials Science & Technology 2016年第5期32卷 459-464页

作者： C.h.Ng O.k.chan h.C.Man Department of Industrial and Systems Engineering The Hong Kong Polytechnic University

Laser gas nitriding （LGN） is a common surface modification method to enhance the wear resistance of titanium （Ti） alloys, which are known to have poor tribological properties. In the present study, a titanium nitride （TIN） grid network was fabricated on the surface of nickel titanium （NiTi） by LGN. The laser processing parameters were selected to achieve nitriding without surface melting and hence to＇maintain a smooth surface finish. The characteristics of the grid-nitrided samples were investigated by scanningelectron microscopy, X-ray diffractometry, optical microscopy, 2-D profilometry, contact angle measurements and nanoindentation. The wear resistance of the nitrided samples was evaluated using reciprocating wear test against ultra-high-molecular-weight polyethylene （UhMWPE） in hanks＇ solution. The results indicate that the wear rates of the grid-nitrided samples and the UhMWPE counter-body in the wear pair are both significantly reduced. The decrease in wear rates can be attributed to the combination of a hard TiN grid and a soft NiTi substrate. In hanks＇ solution, the higher hydrophilicity of the nitrided samples also contributes to the better performance in wear test against hydrophobic UhMWPE.

关键词： Laser Nitriding Surface patterning Titanium alloys Wear

Temperature distribution study during the friction stir welding process of Al2024-T3 aluminum alloy

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International Journal of Minerals,Metallurgy and Materials 2013年第8期20卷 779-787页

作者： Y.h.Yau A.hussain R.k.Lalwani h.k.chan N.hakimi Department of Mechanical Engineering University of Malaya50603 KLMalaysia

heat flux characteristics are critical to good quality welding obtained in the important engineering alloy A12024- T3 by the friction stir welding （FSW） process. In the present study, thermocouples in three different configurations were amxed on the welding samples to measure the temperatures： in the first configuration, four thermocouples were placed at equivalent positions along one side of the welding direction; the second configuration involved two equivalent thermocouple locations on either side of the welding path; while the third configuration had all the thermocouples on one side of the layout but with unequal gaps from the welding line. A three-dimensional, non-linear ANSYS computational model, based on an approach applied to A12024-T3 for the first time, was used to simulate the welding temperature profiles obtained experimentally. The experimental thermal profiles on the whole were found to be in agreement with those calculated by the ANSYS model. The broad agreement between the two kinds of profiles validates the basis for derivation of the simulation model and provides an approach for the FSW simulation in A12024-T3 and is potentially more useful than models derived previously.

关键词： aluminum alloys friction stir welding welds temperature distribution

Comparative chemical sensor for detection of chromium(Ⅵ) in aqueous solution

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Optoelectronics Letters 2025年第1期21卷 21-27页

作者： Sura h.AL-REkABI A.A.ALWAhIB Electrical Technique Department Al Suwayrah Technical Institute Middle Technical University Laser and Optoelectronics Department University of Technology-Iraq

A process for purifying aqueous solutions containing heavy and toxic metals such as chromium（Cr） has been investigated. One of the extremely harmful pollutants in rivers and seawater is the heavy metal ions due to their direct impacts on human, animals and plants are hexavalent Cr（Ⅵ）. Consequently, highly sensitive sensor to detect Cr is essential. Surface plasmon resonance（SPR） technique has attracted huge research interest in detecting heavy metals specifically. In this study, three types of prism-based SPR sensor, gold（Au）/silver（Ag）, Au/polyaniline（PANI） and Au/titanium dioxide（TiO2） nanostructured films, are investigated as potential sensing material to detect the presence of Cr（Ⅵ） ions in water. The base Au layer with thickness of 48.3 nm is deposited on a glass slide for all sensors. For Au/Ag, Au/PANI nanofibers and Au/TiO2sensor films, the Cr（Ⅵ） concentration is varied from 1 ppm to 15 ppm with sensitivity of 0.270 °ppm-1, 0.082 °ppm-1and 0.039 °ppm-1, respectively. Based on these results, the Au/PANI nanofibers are the most sensitive to Cr（Ⅵ） among the tested sensing materials.

关键词： Titanium dioxide

Computing Quantum Bound States on Triply Punctured Two-Sphere Surface

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Chinese Physics Letters 2016年第9期33卷 1-4页

作者： k.T.chan h.Zainuddin k.A.M.Atan A.A.Siddig Department of Physics Faculty of ScienceUniversiti Putra Malaysia Institute for Mathematical Research Universiti Putra Malaysia Department of Physics and Astronomy College of ScienceKing Saud University

We are interested in a quantum mechanical system on a triply punctured two-sphere surface with hyperbolic metric. The bound states on this system are described by the Maass cusp forms （MCFs） which are smooth square integrable eigenfunctions of the hyperbolic Laplacian. Their discrete eigenvalues and the MCF are not known analytically. We solve numerically using a modified hejhal and Then algorithm, which is suitable to compute eigenvalues for a surface with more than one cusp. We report on the computational results of some lower-lying eigenvalues for the triply punctured surface as well as providing plots of the MCF using GridMathematica.

关键词： of in for Computing Quantum Bound States on Triply Punctured Two-Sphere Surface is on MCF