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大兴安岭白桦削度方程

林业科学 2020年第11期56卷 87-96页

作者： Shahzad Muhammad Khurram hussain amna 何培姜立春东北林业大学林学院森林生态系统可持续经营教育部重点实验室哈尔滨150040

【目的】确定预测东北地区白桦不同高度直径和材积的最优削度方程,以弥补该地区没有白桦削度方程的不足。【方法】以伊勒呼里山北坡西北部立地亚区253株白桦伐倒木3795对直径/高度数据为基础,基于林业上广泛应用的8个削度方程,利用SAS... 详细信息

【目的】确定预测东北地区白桦不同高度直径和材积的最优削度方程,以弥补该地区没有白桦削度方程的不足。【方法】以伊勒呼里山北坡西北部立地亚区253株白桦伐倒木3795对直径/高度数据为基础,基于林业上广泛应用的8个削度方程,利用SAS软件的非线性回归SUR法对方程进行拟合。使用一阶连续自回归误差结构模拟方程误差项并解释空间自相关,采用条件数评价方程多重共线性,选择确定系数(R 2)、均方根误差(RMSE)、平均误差绝对值(MAB)和相对误差绝对值(MPB)作为方程评价指标,运用拟合统计量、直径和材积残差分布箱式图及检验统计量进行削度方程的综合比较。【结果】1)从各削度方程拟合统计量来看,Kozak(2004)-2、Fang等(2000)和Max等(1976)方程排在前3位,Sharma等(2001)方程表现最差;2)基于直径和材积残差分布箱式图,Kozak(2004)-2、Fang等(2000)、Max等(1976)和Bi(2000)方程在预测直径和材积时误差较小且具有相似的等方差分布,Sharma等(2001)、Sharma等(2004)、Sharma等(2009)和Kozak(2004)-1方程具有较强的方差异质性;3)模型检验证实Kozak(2004)-2、Fang等(2000)和Max等(1976)方程表现较好,Kozak(2004)-2削度方程在预测直径和材积方面表现出一致性,且优于其他削度方程。【结论】根据模型拟合和检验统计量、图形分析和条件数,Kozak(2004)-2方程被推荐用于预测东北地区白桦不同高度的直径、总材积和商品材积。

关键词：白桦削度材积自相关多重共线性

Steel Surface Defect Recognition in Smart Manufacturing Using Deep Ensemble Transfer Learning-Based Techniques

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Computer Modeling in Engineering & Sciences 2025年第1期142卷 231-250页

作者： Tajmal hussain Jongwon Seok Department of Information and Communication Engineering Changwon National UniversityChangwon51140Republic of Korea

Smart manufacturing and Industry 4.0 are transforming traditional manufacturing processes by utilizing innovative technologies such as the artificial intelligence(AI)and internet of things(IoT)to enhance efficiency,reduce costs,and ensure product *** light of the recent advancement of Industry 4.0,identifying defects has become important for ensuring the quality of products during the manufacturing *** this research,we present an ensemble methodology for accurately classifying hot rolled steel surface defects by combining the strengths of four pre-trained convolutional neural network(CNN)architectures:VGG16,VGG19,Xception,and Mobile-Net V2,compensating for their individual *** evaluated our methodology on the Xsteel surface defect dataset(XSDD),which comprises seven different *** ensemble methodology integrated the predictions of individual models through two methods:model averaging and weighted *** evaluation showed that the model averaging ensemble achieved an accuracy of 98.89%,a recall of 98.92%,a precision of 99.05%,and an F1-score of 98.97%,while the weighted averaging ensemble reached an accuracy of 99.72%,a recall of 99.74%,a precision of 99.67%,and an F1-score of 99.70%.The proposed weighted averaging ensemble model outperformed the model averaging method and the individual models in detecting defects in terms of accuracy,recall,precision,and *** analysis with recent studies also showed the superior performance of our methodology.

关键词： Smart manufacturing CNN steel defects ensemble models

Integral Transform Method for a Porous Slider with Magnetic Field and Velocity Slip

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Computer Modeling in Engineering & Sciences 2020年第3期122卷 1099-1118页

作者： Naeem Faraz Yasir Khan amna Anjum Anwar hussain International Cultural Exchange School(ICES) Donghua UniversityShanghaiChina. Department of Mathematics University of Hafr Al-BatinHafar Al-BatinSaudi Arabia. DBS&HCEME National University of Science and TechnologyIslamabadPakistan.

Current research is about the injection of a viscous fluid in the presence of a transverse uniform magnetic field to reduce the sliding *** is a slip-on both the slider and the ground in the two cases,for example,a long porous slider and a circular porous *** utilizing similarity transformation Navier-Stokes equations are converted into coupled equations which are tackled by Integral Transform *** are obtained for different values of Reynolds numbers,velocity slip,and magnetic *** found that surface slip and Reynolds number has a substantial influence on the lift and drag of long and circular sliders,whereas the magnetic effect is also noticeable.

关键词： Porous slider MHD flow Reynolds number velocity slip integral transform method.

Efficient Simplification Methods for Generating High Quality LODs of 3D Meshes

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Journal of Computer Science & Technology 2009年第3期24卷 604-612,F0003页

作者： Muhammad hussain Department of Computer Science King Saud University

Two simplification algorithms are proposed for automatic decimation of polygonal models, and for generating their LODs. Each algorithm orders vertices according to their priority values and then removes them iteratively. For setting the priority value of each vertex, exploiting normal field of its one-ring neighborhood, we introduce a new measure of geometric fidelity that reflects well the local geometric features of the vertex. After a vertex is selected, using other measures of geometric distortion that are based on normal field deviation and distance measure, it is decided which of the edges incident on the vertex is to be collapsed for removing it. The collapsed edge is substituted with a new vertex whose position is found by minimizing the local quadric error measure. A comparison with the state-of-the-art algorithms reveals that the proposed algorithms are simple to implement, are computationally more efficient, generate LODs with better quality, and preserve salient features even after drastic simplification. The methods are useful for applications such as 3D computer games, virtual reality, where focus is on fast running time, reduced memory overhead, and high quality LODs.

关键词： polygonal models simplification LOD modeling multi-resolution modeling

Mammogram Enhancement Using Lifting Dyadic Wavelet Transform and Normalized Tsallis Entropy

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Journal of Computer Science & Technology 2014年第6期29卷 1048-1057页

作者： Muhammad hussain Department of Software Engineering King Saud University

In this paper, we present a new technique for mammogram enhancement using fast dyadic wavelet transform （FDyWT） based on lifted spline dyadic wavelets and normalized Tsallis entropy. First, a mammogram image is decom- posed into a multiscale hierarchy of low-subband and high-subband images using FDyWT. Then noise is suppressed using normalized Tsallis entropy of the local variance of the modulus of oriented high-subband images. After that, the wavelet coefficients of high-subbands are modified using a non-linear operator and finally the low-subband image at the first scale is modified with power law transformation to suppress background. Though FDyWT is shift-invariant and has better poten- tial for detecting singularities like edges, its performance depends on the choice of dyadic wavclcts. On the other hand, the nulnber of vanishing moments is an important characteristic of dyadic wavelets for singularity analysis because it provides an upper bound measurement for singularity characterization. Using lifting dyadic schemes, we construct lifted spline dyadic wavelets of different degrees with increased number of vanishing moments. We also examine the effect of these wavelets on mammogram enhancement. The method is tested on mammogram images, taken from MIAS （Mammographic Image Analysis Society） database, having various background tissue types and containing different abnormalities. The comparison with tile state-of-the-art contrast enhancement methods reveals that the proposed method performs better and the difference is statistically significant.

关键词： mammogram enhancement lifting dyadic wavelet transform Tsallis entropy

Studies on the effects of pre-firing and sintering temperature on NSDC nanocomposite electrolytes

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Progress in Natural Science:Materials International 2022年第1期32卷 128-134页

作者： Saddam hussain Yangping Li Fida hussain Memon Sabir hussain Lei Li Khalid hussain Thebo State Key Laboratory of Solidification Processing School of Materials Science and Engineering Northwestern Polytechnical University Department of Electrical Engineering Sukkur IBA University Department of Space Science University of the Punjab University of Chinese Academy of Sciences

Solid oxide fuel cells（SOFCs） technology, with fuel flexibility, is one of the most promising power generation technology. However, the high operating temperature of SOFCs has hindered their commercial applications. As a crucial requirement to enhance its performance, SOFCs electrolytes should operate at a low temperature. Carbonate/ceria composites are developed as electrolytes for low operating temperature SOFCs, and a better understanding of the mechanism of its ionic conductivity serves this purpose. In this work, ceria-carbonate composite electrolyte, Na;CO;/samarium doped ceria（NSDC） were synthesized by the co-precipitation *** synthesized electrolytes were characterized by X-ray diffraction（XRD）, scanning electron microscopy（SEM）,X-ray photoelectron spectroscopy（XPS）, and UV–Vis spectroscopy. The XRD and SEM results showed that the sintered NSDC nanocomposite comprised a single-phase dense electrolyte structure. The crystallite size of the NSDC nanocomposite was greatly affected by the different pre-firing temperatures and different sintering temperatures. Also, the ionic conductivity of the prepared NSDC nanocomposite electrolytes was strongly dependent on the pre-firing and sintering temperatures. The NSDC nanocomposite electrolytes were pre-fired at 950°C and650°C and sintered at 1200°C and 900°C respectively, had ionic conductivity in H;and air high as 0.36 S/cm and 0.3 S/cm.

关键词： Solid oxide fuel cell NDSC Composite Electrolyte Ionic conductivity

Ultrasensitive and selective 4-aminophenol chemical sensor development based on nickel oxide nanoparticles decorated carbon nanotube nanocomposites for green environment

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Journal of Environmental Sciences 2017年第3期29卷 27-38页

作者： Mohammad Musarraf hussain Chemistry Department Faculty of ScienceKing Abdulaziz UniversityJeddah 21589P.O.Box 80203Saudi Arabia Center of Excellence for Advanced Material Research(CEAMR) King Abdulaziz UniversityJeddah 21589P.O.Box 80203Saudi Arabia

Nickel oxide nanoparticles decorated carbon nanotube nanocomposites （*** NCs） were prepared in a basic medium by using facile wet-chemical routes. The optical, morphological, and structural properties of *** NCs were characterized using Fourier transformed infra-red （FT-IR）, Ultra-violet visible （UV/Vis） spectroscopy, field-emission scanning electron microscopy （FESEM）, X-ray energy dispersed spectroscopy （XEDS）, X-ray photoelectron spectroscopy （XPS）, and powder X-ray diffraction （XRD） methods. Selective 4-aminophenol （4-AP） chemical sensor was developed by a fiat glassy carbon electrode （GCE, surface area： 0.0316 cm2） fabricated with a thin-layer of NCs. Electrochemical responses including higher sensitivity, large dynamic range （LDR）, limit of detection （LOD）, and long-term stability towards 4-AP were obtained using the fabricated chemical sensors. The calibration curve was found linear （R2 = 0.914） over a wide range of 4-AP concentration （0.1 nmol/L-0.1 tool/L）. In perspective of slope （2 x 10.5 gA/gM）, LOD and sensitivity were calculated as 15.0 ＋ 0.1 pM and -6.33 - 10.4 gA/（***） respectively. The synthesized *** NCs using a wet-chemical method is a significant route for the development of ultrasensitive and selective phenolic sensor based on nano-materials for environmental toxic substances. It is suggested that a pioneer and selective development of 4-AP sensitive sensor using *** NCs by a facile and reliable current us voltage （I-V） method for the major application of toxic agents in biological, green environmental, and health-care fields in near future.

关键词： NiO decorated CNT nanocomposltesOptical evaluationFabricationSensitivity4-AminophenolI-V method

Optimal Islanding for Restoration of Power Distribution Systems Using Prim’s MST Algorithm

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CSEE Journal of Power and Energy Systems 2022年第2期8卷 599-608页

作者： Kaka Sanaullah Mingchao Xia Mazhar hussain Sharafat hussain Ammar Tahir the School of Electrical Engineering Beijing Jiaotong UniversityBeijing 10044China the School of Computer and Information Technology Beijing Jiaotong UniversityBeijing 10044China

Power systems can suffer outages,causing complete or partial disconnection of their power supply to load centers within the distribution *** Generation(DG)plays an essential role in power *** can be used as a back-up power source to enhance the resiliency and reliability of a power *** mode operations after outages in an active distributing network(ADN)is an effective way to maintain continuity of the power supply to significant *** is a quite complicated task for power system operators to find the power flow *** studies have primarily used pre-defined guidelines to find feasible power flow paths,and have focused on multiple islands for *** these studies,possible restoration pathfinding with DG was the fundamental weakness,and furthermore,the power of DG was limited to pre-defined boundaries in the form of ***,in this study,a new algorithm has been proposed,which uses the minimum spanning tree(MST)method to find the most feasible *** proposed algorithm starts at any random node(in this case,DG),and progresses by selecting the next node with the least cost(weight),thus considering all the nodes through which power will *** proposed model is formulated as a multiobjective program considering the priority of loads and minimum power *** effectiveness of the proposed model is tested on a modified IEEE69-bus distribution system with the penetration of multiple distributed generation sources at different *** were compared with the strategies found in literature,and the proposed method was found to be feasible and efficient.

关键词： Active distribution network distributed generation islanding multi-objective minimum spanning tree

The Effect of Spectral Index Parameter κ on Obliquely Propagating Solitary Wave Structures in Magneto-Rotating Plasmas

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Chinese Physics Letters 2012年第6期29卷 211-214页

作者： S.hussain Theoretical Plasma Physics Division PINSTECHNiloreIslamabad 44000Pakistan Department of Physics and Applied Mathematics PIEAS NiloreIslamabad 44000Pakistan

Nonlinear ion-acoustic solitary wave structures in collisionless,non-relativistic,homogenous,magneto-rotating plasma,in which the electron species follow the kappa distribution function,are *** Korteweg-de Vries (KdV) equation is derived by using the reductive perturbation method,and the effects of different plasma parameters on the obliquely propagating nonlinear solitary wave structures in the magneto-rotating plasma are *** is noticed that the spectral index parameter κ significantly modifies the nonlinear wave structure.

关键词： structure rotating solitary