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Exploring the Potential to Uniquely Manufacture Curved VARTM Epoxy Composites Using Cost-Effective FDM Molds

Open Journal of Composite Materials 2020年第3期10卷 45-65页

作者： syed Monis raza Kazmi Jens Schuster Johannes Lutz Hochschule Kaiserslautern University of Applied Sciences Pirmasens Germany

The Resin Infusion or the VARTM (Vacuum Assisted Resin Transfer Molding) process has significant potential to be used to manufacture curved composites. Another way to produce curved or complex geometry is to use 3D printers. 3D or FDM (Fused Deposition Modelling) printers are now being used to produce relatively cheaper curved parts using thermoplastics such as PLA. However, the strength and mechanical performance of these parts is limited and can be enhanced if the polymer is reinforced with a type of fiber for instance. Research is being carried out to produce fiber rein-forced thermoplastic composites but that process is expected to be more expensive than the alternative methods such as injection or compression molding. Furthermore, to understand the manufacture of a hybrid composite using thermoplastics, fibers and epoxy resin, research and investigation need to be carried out. In this research, there are single-sided, double-sided, reusable, disposable and consumable molds. Most of the molds were created either using an FDM printer or manually. These molds were then used to manufacture flat and curved composite structures via the resin injection process, i.e. VARTM with epoxy resin system and glass/carbon/flax fiber reinforcement. By replacing the costly metallic molds by significantly cheaper molds, the cost of production was expected to further reduce. Furthermore, using double-sided PLA molds was not expected to be a threat to the overall cost of the composite part in question compared to double-sided matched molds used in compression molding. Shear

关键词： 3D Printing FDM VARTM Curved Composites 3D Molds Reusable Molds Consumable Molds Disposable Molds

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Quantum Theory of Mesoscopic Fractional Electric Fields in a Cavity of Viscous Medium

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World Journal of Condensed Matter Physics 2016年第1期6卷 39-44页

作者： Saleem Iqbal Salma Jabeen Farhana Sarwar syed Mohsin raza Department of Mathematics University of Balochistan Quetta Pakistan Department of Physics University of Balochistan Quetta Pakistan Department of Mathematics F. G. Girls Degree College Quetta Cantt Pakistan

With conjecture of fractional charge quantization (quantum dipole/multiple moments), Fourier transform stretching, twisting and twigging of an electron quanta and waver strings of electron quanta, the mathematical expressions for mesoscopic fractional electron fields in a cavity of viscous medium and the associated quantum dielectric susceptibility are developed. Agreement of this approach is experimentally evidenced on barite and Fanja site molecular sieves. These findings are in conformity with experimental results of 2012 Physics Nobel prize winning scientists, Serge Haroche and David J. Wineland especially for cavity quantum electro-dynamics electron and its associated mesoscopic electric fields. The mover electron quanta strings lead to warping of space and time following the behaviour of quantum electron dynamics.

关键词： Mesoscopic Fractional Electric Fields Quantum Dielectric Susceptibility Giant Magneto Resistance (GMR) Fourier Transform (FT) Woven Strings of Electron Quanta Warping of Space and Time Following QED (Quantum Electrodynamics)

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Incidental gallbladder cancer diagnosis confers survival advantage irrespective of tumour stage and characteristics

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World Journal of Gastroenterology 2022年第18期28卷 1996-2007页

作者： Moath Alarabiyat syed Soulat raza John Isaac Darius Mirza Ravi Marudanayagam Keith Roberts Manuel Abradelo David C Bartlett Bobby V Dasari Robert P Sutcliffe Nikolaos A Chatzizacharias HPB and Liver Transplant Unit Queen Elizabeth HospitalBirmingham B152GWUnited Kingdom Department of HPB and Liver Transplantation Queen Elizabeth HospitalUniversity Hospitals BirminghamBirmingham B152THUnited Kingdom

BACKGROUND Incidental gallbladder cancer(IGBC)represents 50%-60%of gallbladder cancer *** are conflicting on the role of IGBC diagnosis in oncological *** studies suggest that IGBC diagnosis does not affect outcomes,while others that overall survival(OS)is longer in these cases compared to non-incidental diagnosis(NIGBC).Furthermore,some studies reported early tumour stages and histopathologic characteristics as possible confounders,while others *** To investigate the role of IGBC diagnosis on patients’overall survival,especially after surgical treatment with curative *** Retrospective analysis of all patient referrals with gallbladder cancer between 2008 and 2020 in a tertiary hepatobiliary *** comparison of patient and tumour characteristics between IGBC and NIGBC subgroups was *** analysis for the whole cohort,surgical and non-surgical subgroups was done with the Kaplan-Meier method and the use of log rank *** analysis was performed with univariable and multivariable Cox regression *** The cohort included 261 patients with gallbladder cancer.65%of cases had NIGBC and 35%had IGBC.A total of 90 patients received surgical treatment(66%of IGBC cases and 19%of NIGBC cases).NIGBC patients had more advanced T stage and required more extensive resections than IGBC *** was longer in patients with IGBC in the whole cohort(29 vs 4 mo,P<0.001),as well as in the non-surgical(14 vs 2 mo,P<0.001)and surgical subgroups(29 vs 16.5 mo,P=0.001).Disease free survival(DFS)after surgery was longer in patients with IGBC(21.5 mo vs 8.5 mo,P=0.007).N stage and resection margin status were identified as independent predictors of OS and *** diagnosis was identified as an independent predictor of *** IGBC diagnosis may confer a survival advantage independently of the pathological stage and tumour *** studies are required to further investigate this,including detailed

关键词： Gallbladder cancer Incidental gallbladder cancer Non-incidental gallbladder cancer Gallbladder cancer survival

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Numerical Simulation of Char Particle Gasification

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Journal of Energy and Power Engineering 2015年第8期9卷 679-686页

作者： syed Shabbar raza Isam Janajreh Rizwan Ahmed Ashjan AlKatheeri Waste to Energy Lab Masdar Institute of Science and Technology Abu Dhabi 54224 UAE Takreer Research Center Abu Dhabi 3593 UAE

A first principal modeling of the gasification of a char particle is performed using single step mechanism. The char particle is considered to be spherical in shape and only the physical and chemical properties can change in the radial direction. The carbon dioxide is used as the gasification agent that reacts with the char and form carbon monoxide. The presence of both solid and gaseous phase species makes the reaction heterogeneous. The char particle is considered with varying porosity that also allows the change in the surface area of the particle. A time invariant temperature and pressure profile is used at which the Arrhenius rate constant and diffusion is calculated. The mass conservation of model results in the form of two coupled partial differential and one ordinary differential equation. The equations are solved with a set of initial and boundary conditions using the bulk species concentration at the particle surface. A second order accurate central differencing scheme is used to discretize space while backward differencing is used to discretize time. Finally, the results are presented for the concentration distribution of CO and CO2 in radial direction with respect to time. It shows that, maximum concentration of CO is present at the center of the particle while the concentration gradient becomes higher near the particle surface. The nonlinear concentration trend due to the diffusion is effectively captured. The results show that, completed conversion of char depend upon the time provided for the reaction which can be reduced by decreasing the size of particle or increasing the reaction temperature. The sensitivity study of temperature and initial porosity also performed and showed that temperature has high impact on char conversion as compare to initial porosity.

关键词： Coal particle conversion biomass porosity CO2 gasification.

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基于LCTF成像仪的光谱反射率测量研究

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红外与激光工程 2022年第10期51卷 182-189页

作者：宋宏张杨帆杨萍吴超鹏汪孟杰李梓欣 syed raza Mehdi 王天亮黄慧浙江大学海洋学院浙江舟山316021 杭州电子科技大学数字媒体与艺术设计学院浙江杭州310018 浙江大学海南研究院海南三亚572024

目标物体的光谱反射率是水下光谱检测中重要的物理特性。复杂的水下环境,尤其是浑浊水体对光有较强的吸收与散射作用,增大了光谱探测的难度。文中在比对测量法的基础上,提出了引入黑、白板对测量结果进行矫正的光谱反射率探测方法。利... 详细信息

目标物体的光谱反射率是水下光谱检测中重要的物理特性。复杂的水下环境,尤其是浑浊水体对光有较强的吸收与散射作用,增大了光谱探测的难度。文中在比对测量法的基础上,提出了引入黑、白板对测量结果进行矫正的光谱反射率探测方法。利用基于液晶可调谐滤光片的水下光谱成像仪快速稳定地采集多浊度、多光照条件下的光谱图像数据。数据分析结果证明了浊度增加会使得黑、白板的像素响应比值非线性增加,尤其在400~500 nm范围内。且基于黑白板的光谱反射率探测方法可以有效去除水体散射对光谱反射率重建的影响,使得不同浊度条件下得到的目标物光谱反射率最大绝对误差为5.3%。

关键词：水下光谱成像 LCTF 水体浑浊度光谱反射率探测

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无棒标识的下肢生物力学模型在步行和跑步运动分析中的应用（英文）

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纳米技术与精密工程 2015年第5期13卷 383-390页

作者： Ghaffar Muhammad raza syed Arnold Graham Abboud Rami 王威杰英国邓迪大学运动分析研究所矫形及创伤外科系泰滨矫形及康复技术中心巴基斯坦NED理工大学生物医学工程系卡拉奇78000

生物力学模型在运动分析中具有重要作用.目前,一些常用的传统模型带有有棒标识,可能在运动中产生振动,引起误差.本文提出一种下肢无棒标识模型,可以计算下肢关节的角度、力、力矩和功.为了验证新模型,22个健康成人参加了试验,分别应用... 详细信息

生物力学模型在运动分析中具有重要作用.目前,一些常用的传统模型带有有棒标识,可能在运动中产生振动,引起误差.本文提出一种下肢无棒标识模型,可以计算下肢关节的角度、力、力矩和功.为了验证新模型,22个健康成人参加了试验,分别应用新模型和传统模型分析了他们的步行和跑步标识数据,计算并比较了其下肢的踝、膝、髋关节的角度、力、力矩和功.基于所有参数曲线,误差分析结果显示:高频振动引起的误差在传统模型中比在新模型中大一倍.可靠性分析显示:新模型的内联相关系数在步行和跑步中分别达到0.934和0.960,而传统模型分别只有0.737和0.916.结果表明新模型比传统的有棒标识模型在减少误差和提高可靠性方面均有改善.新的无棒标识下肢生物力学模型可以取代传统有棒标识下肢模型,用于医疗步态和跑步的运动分析.

关键词：生物力学模型可靠性误差分析下肢关节步行跑步

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A Meta-Learning Approach for Aircraft Trajectory Prediction

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Communications and Network 2023年第2期15卷 43-64页

作者： syed Ibtehaj raza Rizvi Jamal Habibi Markani René Jr. Landry É cole de technologies supérieure (&#201TS) Montréal Canada

The aviation industry has seen significant advancements in safety procedures over the past few decades, resulting in a steady decline in aviation deaths worldwide. However, the safety standards in General Aviation (GA) are still lower compared to those in commercial aviation. With the anticipated growth in air travel, there is an imminent need to improve operational safety in GA. One way to improve aircraft and operational safety is through trajectory prediction. Trajectory prediction plays a key role in optimizing air traffic control and improving overall flight safety. This paper proposes a meta-learning approach to predict short- to mid-term trajectories of aircraft using historical real flight data collected from multiple GA aircraft. The proposed solution brings together multiple models to improve prediction accuracy. In this paper, we are combining two models, Random Forest Regression (RFR) and Long Short-term Memory (LSTM), using k-Nearest Neighbors (k-NN), to output the final prediction based on the combined output of the individual models. This approach gives our model an edge over single-model predictions. We present the results of our meta-learner and evaluate its performance against individual models using the Mean Absolute Error (MAE), Absolute Altitude Error (AAE), and Root Mean Squared Error (RMSE) evaluation metrics. The proposed methodology for aircraft trajectory forecasting is discussed in detail, accompanied by a literature review and an overview of the data preprocessing techniques used. The results demonstrate that the proposed meta-learner outperforms individual models in terms of accuracy, providing a more robust and proactive approach to improve operational safety in GA.

关键词： Trajectory Prediction General Aviation Safety Meta-Learning Random Forest Regression Long Short-Term Memory Short to Mid-Term Trajectory Prediction Operational Safety

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Trajectory of cause of death among brought dead neonates in tertiary care public facilities of Pakistan: A multicenter study

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World Journal of Pediatrics 2017年第1期13卷 57-62页

作者： Muhammad Ayaz Mustufa Munir Ahmed Sheikh Ijaz-ul-Haque Taseer syed Jamal raza Muhammad Sohail Arshad Tasleem Akhter Ghazala Mohyuddin Arain Sultana Habibuilah Sohail Safdar Rukhsana Firdous Muhammad Adnan PMRC Specialized Research Center on Child Health National Institute of Child HealthKarachiPakistan PMRC Research Center Liaquat University of Health and Medical SciencesJamshoroHyderabadPakistan PMRC Research Center Nishtar MedicaI CollegeMultan.Pakistan PMRC Research Center Khyber Medical CollegePeshawarPakistan PMRC Research Center Punjab Medical CollegeFaisalabad.Pakistan PMRC Research Center Dow University of Health Sciences.Karachi.Pakistan PMRC Research Center Bolan Medical CollegeOuettaPakistan PMRc Research Center FJMCLahore.Pakistan.

Background:Considering the fact that Pakistan is amongst the countries with very high neonatal mortality rates,we conducted a research study to determine the possible causes and characteris廿cs of neonates presenting dead to the emergency department of tertiary public health care facilities of Pakistan using verbal ***:A descriptive case series study was conducted in emergency department/pediatrics ward/neonatal ward/nursery unit of ten tertiary care public health facilities,situated in seven malor cities of Pakistan from November,2011 to June。*** verbal autopsy proforma was used to collect information regarding cause of death,family narratives and other associated risks accountable for pathway to mortality.

关键词： autopsy child health services early childhood emergency department use neonatal mortality

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Mesenchymal stem cell-derived exosomes:Shaping the next era of stroke treatment

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Neuroprotection 2023年第2期1卷 99-116页

作者： Arshi Waseem Saudamini Rizwanul Haque Miroslaw Janowski syed S.raza Laboratory for Stem Cell&Restorative Neurology Department of BiotechnologyEra's Lucknow Medical College HospitalEra UniversitySarfarazganjLucknowIndia Department of Biotechnology Central University of South BiharGayaIndia Center for Advanced Imaging Research Department of Diagnostic Radiology and Nuclear MedicineUniversity of MarylandBaltimoreMarylandUSA Department of Stem Cell Biology and Regenerative Medicine Era's Lucknow Medical College HospitalEra UniversitySarfarazganjLucknowIndia

Exosome-based treatments are gaining traction as a viable approach to addressing the various issues faced by an ischemic *** extracellular vesicles,mainly produced by mesenchymal stem cells,exhibit many properties with substantial therapeutic *** are particularly appealing for stroke therapy because of their low immunogenicity,effective cargo transport,and ability to cross the blood–brain *** diverse effects include neuroprotection,angiogenesis stimulation,inflammatory response modulation,and cell death pathway attenuation,synergistically promoting neuronal survival,tissue regeneration,and functional *** also show potential as diagnostic indicators for early stroke identification and customized treatment *** these promising qualities,current exosome-based therapeutics have some *** heterogeneity of exosome release among cell types,difficulty in standardization and isolation techniques,and complications linked to dosage and targeted administration necessitates extensive *** is critical to thoroughly understand exosomal processes and their complicated interactions within the cellular *** improve the practicality and efficacy of exosome-based medicines,research efforts must focus on improving production processes,developing robust evaluation criteria,and developing large-scale isolation ***,exosomes’multifunctional properties offer a new route for transforming stroke treatment and significantly improving patient outcomes.

关键词： exosomes inflammatory stress ischemic stroke mesenchymal stem cells middle cerebral artery occlusion oxidative stress

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Application of Electrodynamic Theory on Quantum Hall Effect

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World Journal of Condensed Matter Physics 2016年第2期6卷 87-94页

作者： Saleem Iqbal Muhammad Zafar Farhana Sarwar syed Mohsin raza Muhammad Afzal Rana Department of Mathematics University of Balochistan Quetta Pakistan Department of Basic Sciences Riphah International University Islamabad Pakistan Department of Mathematics F. G. Girls Degree College Quetta Pakistan Department of Physics University of Balochistan Quetta Pakistan

The quantum electrodynamic (QED) behaviour is studied for quantum Hall effect (QHE). Quantum theory with conjecture of fractional charge quantization (quantum dipole moment), eigenfunctions for fractional charge quantization at the surface of a twisted and twigged electron quanta and above its surface, fractional Fourier transform and Hermite function for fractional charge quantization is developed. With energy eigen value equation for QHE and with energy operator on an eigenfunction of a twisted and twigged electron quanta, the corresponding eigenfunctions are normalized with Schrodinger’s quantum wave mechanical equation for electric scalar and magnetic potentials, respectively (QED behavior). The fractional electric and magnetic fields with their corresponding potentials for the quantized fractional states in semiconducting hereto structures are theoretically calculated. Such mathematical expressions are in good agreement with experimental results of Nobel Prize winning scientists Klitzing, Haroche, Peter and Gruebber. Our results can also explain the hybridized states of orbits with emphasis on sigma and pi bonding and their corresponding antibonding orbitals as a manifestation of electrophilic and nucleophilic chemical reactions.

关键词： Fractional Charge Quantization Fractional Fourier Transform Quantum Hall Effect Quantum Electrodynamics Electron Quanta String Twisted and Twigged Electron Quanta

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