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3D Kronecker Convolutional Feature Pyramid for Brain Tumor Semantic Segmentation in MR Imaging

Computers, Materials & Continua 2023年第9期76卷 2861-2877页

作者： Kainat Nazir Tahir Mustafa Madni Uzair Iqbal Janjua umer javed Muhammad Attique Khan Usman Tariq Jae-Hyuk Cha Medical Imaging and Diagnostics Lab NCAIDepartment of Computer ScienceCOMSATS University IslamabadIslamabad44000Pakistan Department of Electrical and Computer Engineering COMSATS University IslamabadWah CampusWahPakistan Department of Computer Science HITEC UniversityTaxilaPakistan Department of Management Information Systems College of Business AdministrationPrince Sattam Bin Abdulaziz UniversityAl-Kharj16273Saudi Arabia Department of Computer Science Hanyang UniversitySeoul04763Korea

Brain tumor significantly impacts the quality of life and changes everything for a patient and their loved ones.Diagnosing a brain tumor usually begins with magnetic resonance imaging(MRI).The manual brain tumor diagnosis from the MRO images always requires an expert radiologist.However,this process is time-consuming and costly.Therefore,a computerized technique is required for brain tumor detection in MRI images.Using the MRI,a novel mechanism of the three-dimensional(3D)Kronecker convolution feature pyramid(KCFP)is used to segment brain tumors,resolving the pixel loss and weak processing of multi-scale lesions.A single dilation rate was replaced with the 3D Kronecker convolution,while local feature learning was performed using the 3D Feature Selection(3DFSC).A 3D KCFP was added at the end of 3DFSC to resolve weak processing of multi-scale lesions,yielding efficient segmentation of brain tumors of different sizes.A 3D connected component analysis with a global threshold was used as a post-processing technique.The standard Multimodal Brain Tumor Segmentation 2020 dataset was used for model validation.Our 3D KCFP model performed exceptionally well compared to other benchmark schemes with a dice similarity coefficient of 0.90,0.80,and 0.84 for the whole tumor,enhancing tumor,and tumor core,respectively.Overall,the proposed model was efficient in brain tumor segmentation,which may facilitate medical practitioners for an appropriate diagnosis for future treatment planning.

关键词： Brain tumor segmentation connect component analysis deep learning kronecker convolution magnetic resonance imaging

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A Hybrid Attention-Based Residual Unet for Semantic Segmentation of Brain Tumor

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Computers, Materials & Continua 2023年第7期76卷 647-664页

作者： Wajiha Rahim Khan Tahir Mustafa Madni Uzair Iqbal Janjua umer javed Muhammad Attique Khan Majed Alhaisoni Usman Tariq Jae-Hyuk Cha Department of Computer Science COMSATS University IslamabadIslamabad45550Pakistan Department of Electrical and Computer Engineering COMSATS University IslamabadWah CampusPakistan Department of Computer Science HITEC UniversityTaxilaPakistan Department of Computer Science College of Computer and Information SciencesPrincess Nourah bint Abdulrahman UniversityRiyadh11671Saudi Arabia Department of Management Information Systems CoBAPrince Sattam Bin Abdulaziz UniversityAl-Kharj16273Saudi Arabia Department of Computer Science Hanyang UniversitySeoul04763Korea

Segmenting brain tumors in Magnetic Resonance Imaging(MRI)volumes is challenging due to their diffuse and irregular shapes.Recently,2D and 3D deep neural networks have become famous for medical image segmentation because of the availability of labelled datasets.However,3D networks can be computationally expensive and require significant training resources.This research proposes a 3D deep learning model for brain tumor segmentation that uses lightweight feature extraction modules to improve performance without compromising contextual information or accuracy.The proposed model,called Hybrid Attention-Based Residual Unet(HA-RUnet),is based on the Unet architecture and utilizes residual blocks to extract low-and high-level features from MRI volumes.Attention and Squeeze-Excitation(SE)modules are also integrated at different levels to learn attention-aware features adaptively within local and global receptive fields.The proposed model was trained on the BraTS-2020 dataset and achieved a dice score of 0.867,0.813,and 0.787,as well as a sensitivity of 0.93,0.88,and 0.83 for Whole Tumor,Tumor Core,and Enhancing Tumor,on test dataset respectively.Experimental results show that the proposed HA-RUnet model outperforms the ResUnet and AResUnet base models while having a smaller number of parameters than other state-of-the-art models.Overall,the proposed HA-RUnet model can improve brain tumor segmentation accuracy and facilitate appropriate diagnosis and treatment planning for medical practitioners.

关键词： MRI volumes residual Unet BraTs-2020 squeeze-excitation(SE)

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Computational Algorithms for the Analysis of Cancer Virotherapy Model

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Computers, Materials & Continua 2022年第5期71卷 3621-3634页

作者： Ali Raza Dumitru Baleanu Muhammad Rafiq Syed Zaheer Abbas Abubakar Siddique umer javed Mehvish Naz Arooj Fatima Tayyba Munawar Hira Batool Zaighum Nazir Department of Mathematics Govt.Maulana Zafar Ali Khan Graduate College Wazirabad52000Punjab Higher Education Department(PHED)Lahore54000Pakistan Department of Mathematics University of SialkotSialkot51310Pakistan Department of Mathematics Cankaya UniversityBalgatAnkara06530Turkey Department of Medical Research China Medical UniversityTaichung40402Taiwan Department of Mathematics Faculty of SciencesUniversity of Central PunjabLahore54500Pakistan Department of Mathematics National College of Business Administration and EconomicsLahore54660Pakistan Department of Mathematics COMSATS University IslamabadWah CampusQuaid AvenueWah Cantonment47040Pakistan Department of Electrical and Computer Engineering COMSATS University IslamabadWah CampusQuaid AvenueWah Cantonment47040Pakistan

Cancer is a common term for many diseases that can affect any part of the body.In 2020,ten million people will die due to cancer.A worldwide leading cause of death is cancer by the World Health Organization(WHO)report.Interaction of cancer cells,viral therapy,and immune response are identified in this model.Mathematical and computational modeling is an effective tool to predict the dynamics of cancer virotherapy.The cell population is categorized into three parts like uninfected cells(x),infected cells(y),virus-free cells(v),and immune cells(z).The modeling of cancerlike diseases is based on the law of mass action(the rate of change of reacting substances is directly proportional to the product of interacting substances).Positivity,boundedness,equilibria,threshold analysis,are part of deterministic modeling.Later on,a numerical analysis is designed by using the standard and non-standard finite difference methods.The non-standard finite difference method is developed to study the long-term behavior of the cancer model.For its efficiency,a comparison of the methods is investigated.

关键词： Cancer disease epidemic model algorithms stability analysis

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A Finite Difference Method and Effective Modification of Gradient Descent Optimization Algorithm for MHD Fluid Flow Over a Linearly Stretching Surface

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Computers, Materials & Continua 2020年第2期62卷 657-677页

作者： Yasir Nawaz Muhammad Shoaib Arif Mairaj Bibi Javeria Nawaz Abbasi umer javed Amna Nazeer Stochastic Analysis&Optimization Research Group Department of MathematicsAir UniversityPAF Complex E-9Islamabad44000Pakistan Department of Mathematics Comsats UniversityChak Shahzad CampusIslamabad44000Pakistan Department of Electrical and Computer Engineering Comsats UniversityIslamabadWah CampusWah Cantt47040Pakistan

Present contribution is concerned with the construction and application of a numerical method for the fluid flow problem over a linearly stretching surface with the modification of standard Gradient descent Algorithm to solve the resulted difference equation.The flow problem is constructed using continuity,and Navier Stoke equations and these PDEs are further converted into boundary value problem by applying suitable similarity transformations.A central finite difference method is proposed that gives third-order accuracy using three grid points.The stability conditions of the present proposed method using a Gauss-Seidel iterative procedure is found using Von-Neumann stability criteria and order of the finite difference method is proved by applying the Taylor series on the discretised equation.The comparison of the presently modified optimisation algorithm with the Gauss-Seidel iterative method and standard Newton’s method in optimisation is also made.It can be concluded that the presently modified optimisation Algorithm takes a few iterations to converge with a small value of the parameter contained in it compared with the standard descent algorithm that may take millions of iterations to converge.The present modification of the steepest descent method converges faster than Gauss-Seidel method and standard steepest descent method,and it may also overcome the deficiency of singular hessian arise in Newton’s method for some of the cases that may arise in optimisation problem(s).

关键词： Magnetohydrodynamic exact finite difference scheme optimization algorithm stability&convergence

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A Reliable Stochastic Numerical Analysis for Typhoid Fever Incorporating With Protection Against Infection

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Computers, Materials & Continua 2019年第6期59卷 787-804页

作者： Muhammad Shoaib Arif Ali Raza Muhammad Rafiq Mairaj Bibi Rabia Fayyaz Mehvish Naz umer javed Department of Mathematics Air UniversityPAF Complex E-9Islamabad44000Pakistan Faculty of Engineering University of Central PunjabLahore54500Pakistan Department of Mathematics Comsats UniversityChak Shahzad CampusIslamabad44000Pakistan Department of Electrical and Computer Engineering Comsats UniversityWah Campus47040IslambadPakistan

In this paper,a reliable stochastic numerical analysis for typhoid fever incorporating with protection against infection has been considered.We have compared the solutions of stochastic and deterministic typhoid fever model.It has been shown that the stochastic typhoid fever model is more realistic as compared to the deterministic typhoid fever model.The effect of threshold number T*hold in stochastic typhoid fever model.The proposed framework of the stochastic non-standard finite difference scheme(SNSFD)preserves all dynamical properties like positivity,bounded-ness and dynamical consistency defined by Mickens,R.E.The stochastic numerical simulation of the model showed that increase in protection leads to low disease prevalence in a population.

关键词： Typhoid fever stochastic differential equations euler maruyama scheme stochastic euler scheme stochastic runge-kutta scheme stochastic NSFD scheme

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Numerical Simulations for Stochastic Computer Virus Propagation Model

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Computers, Materials & Continua 2020年第1期62卷 61-77页

作者： Muhammad Shoaib Arif Ali Raza Muhammad Rafiq Mairaj Bibi Javeria Nawaz Abbasi Amna Nazeer umer javed Stochastic Analysis&Optimization Research Group Department of MathematicsAir UniversityPAF Complex E-9IslamabadPakistan Faculty of Engineering University of Central Punjab LahorePakistan Department of Mathematics Comsats UniversityChak Shahzad CampusIslamabadPakistan Department of Electrical and Computer Engineering Comsats UniversityWah CampusIslamabadPakistan

We are presenting the numerical simulations for the stochastic computer virus propagation model in this manuscript.We are comparing the solutions of stochastic and deterministic computer virus models.Outcomes of a threshold number R0 hold in stochastic computer virus model.If R_(0)1 shows virus rapidly spread in the computer population.Unfortunately,stochastic numerical techniques fail to cope with large step sizes of time.The suggested structure of the stochastic non-standard finite difference technique can never violate the dynamical properties.On this basis,we can suggest a collection of strategies for removing virus’s propagation in the computer population.

关键词： Computer virus propagation model Stochastic modelling Stochastic processes Stochastic techniques Convergence analysis

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Frequency hopping in IEEE 802.15.4 to mitigate IEEE 802.11 interference and fading

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Journal of Systems Engineering and Electronics 2018年第3期29卷 445-455页

作者： javed umer HE Di LIU Peilin YANG Yueming Shanghai Key Laboratory of Navigation and Location-based Services Shanghai Jiao Tong University Shanghai Panchip Microelectronics Co. Ltd

In this paper, we investigate the issues of initialization and deployment of wireless sensor networks（WSNs） under IEEE 802.11 b/g interference and fading channels using frequency hopping（FH）. We propose an FH algorithm for WSNs, which is implemented and tested with a pair of nodes employing IPv6 over low power wireless personal area networks（6 LoWPAN） standard.The merits and demerits of the proposed FH scheme in WSNs are studied under strong IEEE 802.11 b/g interference and frequency selective fading channels. We compare the performance results of the proposed FH scheme with those obtained by single-channel radio in WSNs, and show that FH maintains very reliable data rates in the presence of adverse conditions where the single-channel radio fails. We determine a minimum center frequency offset of channels between IEEE 802.15.4 and IEEE 802.11 b/g-based networks, which guarantees the error free network operation of IEEE802.15.4 using a single channel. We design a second FH procedure comprising only four free channels（15, 20, 25, and 26） of IEEE 802.15.4 standard, and show that in the presence of nearby IEEE 802.11 b/g interference, the IEEE 802.15.4 data rate using this method is always 98% and more.

关键词： IEEE 802.15.4 wireless sensor networks（WSNs） frequency hopping（FH） interference avoidance coexistence

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链霉素和赤霉素诱导欧亚种葡萄‘玫瑰香’无核结实的效果及机制研究

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果树学报 2020年第6期37卷 830-837页

作者：赵茂香郑伟尉 Hafiz umer javed 王世平浙江农林大学农业与食品科学学院杭州311300 上海交通大学农业与生物学院上海200240

【目的】探讨链霉素(SM)及赤霉素(GAs)诱导欧亚种葡萄有核品种无核结实的可行性及其诱导无核结实的机制。【方法】以8 a(年)生欧亚种葡萄有核品种‘玫瑰香’为实验材料,在满花前11 d至满花后4 d的2周期间用SM 200mg·L^-1、GAs40 mg·L... 详细信息

【目的】探讨链霉素(SM)及赤霉素(GAs)诱导欧亚种葡萄有核品种无核结实的可行性及其诱导无核结实的机制。【方法】以8 a(年)生欧亚种葡萄有核品种‘玫瑰香’为实验材料,在满花前11 d至满花后4 d的2周期间用SM 200mg·L^-1、GAs40 mg·L^-1水溶液分别浸蘸花穗,探讨适宜使用时期。在满花当日用不同浓度SM、GAs及SM和GAs的混合液浸蘸花穗,探讨适宜使用浓度,并和GA3处理作了比较。所有处理花后2周再次用25 mg·L^-1的GAs溶液浸蘸果穗促进果粒膨大。【结果】从满花前7 d到满花后4 d期间用SM 200 mg·L^-1浸蘸花穗,各处理无核率都达100%。满花当日使用SM 50 mg·L^-1和100 mg·L^-1处理的无核率接近100%,SM 200 mg·L^-1+GAs25 mg·L^-1和SM 200 mg·L^-1+GAs40mg·L^-1无核率也达100%。但同期的GAs和GA3处理无核率较低。切片观察发现,SM各处理虽然使柱头花粉粒萌发及花粉管在雌蕊各部位的伸长都受到抑制,但到达珠孔的花粉管数目仍有0.8~1.4个(对照3.8个)。而满花当日的正常胚珠率、胚囊率却低于16.6%(对照为94.17%)。【结论】满花前1周至满花后4 d期间,SM 200 mg·L^-1单用或添加GAs25 mg·L^-1的水溶液浸蘸葡萄的花穗可以有效诱导欧亚种葡萄的无核结实。SM处理后雌蕊的胚珠和胚囊发育异常,是其诱导无核结实的主要原因。赤霉素对欧亚种葡萄的无核效果较差,有待进一步研究。

关键词： ‘玖瑰香’葡萄链霉素赤霉素无核结实效果机制

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基于超螺旋算法的机器人鲁棒跟踪控制研究

基于超螺旋算法的机器人鲁棒跟踪控制研究

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作者： Muhammad umer javed 广东海洋大学

学位级别：硕士

在过去的几十年里,机器人系统成为各行各业中最重要的组成部分。机器人被用在我们需要更精确更快速的场合。机械设备自动化和自动化生产线是现代工业加工制造业发展的必然趋势。未来的工厂机器人将把人类从单调的手工劳动中解放出来。... 详细信息

在过去的几十年里,机器人系统成为各行各业中最重要的组成部分。机器人被用在我们需要更精确更快速的场合。机械设备自动化和自动化生产线是现代工业加工制造业发展的必然趋势。未来的工厂机器人将把人类从单调的手工劳动中解放出来。机器人系统成为汽车制造、焊接、零部件移动、高温等人类无法工作的场合中最重要的组成部分。为此,为了提高机器人的跟踪精度和鲁棒性,提出了几种机器人跟踪控制方法。首先,提出了一种滑模控制器,该控制器具有良好的鲁棒性,但不可避免的“抖振”现象会产生未建模的动态,从而破坏物理系统。为了避免这一缺点,将采用超螺旋转算法。超扭转算法的轨迹跟踪时间较短,但也存在启动时间超调的缺点。针对这一缺点,提出了一种新的快速超螺旋算法。该方法在时间和轨迹跟踪方面均取得了较好的效果。所有方法的稳定性均由李亚普诺夫稳定性定律证明。为了验证该方法的有效性,选择了二自由度机械手平台进行实验。FPGA cotntroller是基于LabVIEW软件设计的,编程简单,实时性好。实验表明,该方法具有良好的跟踪性能,跟踪误差不超过0.005弧度。

关键词：鲁棒跟踪控制滑模控制 Super-twisting算法震动衰减机械臂

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Sandwich structures with tapered tubes as core:A quasi-static investigation

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Defence Technology（防务技术） 2024年第3期33卷 447-462页

作者： Xinmei Xiang Dehua Shao Xin Zhang umer Sharif Ngoc San Ha Li Xiang Jing Zhang Jiang Yi School of Civil Engineering Guangzhou UniversityGuangzhouChina Department of Mechanics and Aerospace Engineering Southern University of Science and TechnologyShenzhenGuangdongChina School of Engineering Centre for Innovative Structures and MaterialsRMIT UniversityMelbourneAustralia China Southern Airlines Co. LtdShenzhen BranchShenzhen518000China

In this article,the experimental and finite element analysis is utilized to investigate the quasi-static compression features of sandwich constructions built with tapered tubes.3D printing technology was utilized to create the hollow centers of the tapering tubes,with and without corrugations.The results demonstrate that the energy absorption(EA)and specific energy absorption(SEA)of the single corrugated tapered tube sandwich are 51.6% and 19.8% higher,respectively,than those of the conical tube sandwich.Furthermore,the results demonstrate that energy absorbers can benefit from corrugation in order to increase their efficiency.Additionally,the tapered corrugated tubes'resistance to oblique impacts was studied.Compared to a straight tube,the tapered tube is more resistant to oblique loads and has a lower initial peak crushing force(PCF),according to numerical simulations.After conducting a parametric study,it was discovered that the energy absorption performance of the sandwich construction is significantly affected by the amplitude,number of corrugations,and wall thickness.EA and SEA of DTS with corrugation number of 8 increased by 17.4%and 29.6%,respectively,while PCF decreased by 9.2% compared to DTS with corrugation number of 10.

关键词： Sandwich structure Corrugated tube Tapered tube Quasi-static Energy absorption

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