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Effects of helium massive gas injection level on disruption mitigation on EAST

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Plasma Science and Technology 2021年第7期23卷 31-38页

作者： abdullah zafar Ping ZHU Ahmad ALI Shiyong ZENG Haolong LI CAS Key Laboratory of Geospace Environment and Department of Engineering and Applied Physics University of Science and Technology of ChinaHefei 230026Peopleʼs Republic of China International Joint Research Laboratory of Magnetic Confinement Fusion and Plasma Physics State Key Laboratory of Advanced Electromagnetic Engineering and TechnologySchool of Electrical and Electronic EngineeringHuazhong University of Science and TechnologyWuhan 430074Peopleʼs Republic of China Department of Engineering Physics University of Wisconsin-MadisonMadisonWI 53706United States of America Pakistan Tokamak Plasma Research Institute Islamabad 3329Pakistan Department of Plasma Physics and Fusion Engineering University of Science and Technology of ChinaHefei 230026People’s Republic of China

In this study,NIMROD simulations are performed to investigate the effects of massive helium gas injection level on the induced disruption on EAST *** is demonstrated in simulations that two different scenarios of plasma cooling(complete cooling and partial cooling)take place for different amounts of injected *** the impurity injection above a critical level,a single MHD activity is able to induce a complete core temperature *** impurity injection below the critical level,a series of multiple minor disruptions occur before the complete thermal quench.

关键词： massive gas injection MHD instabilities major disruption minor disruption

Dependence of Nucleon and Pion-Induced Fission Cross Sections on the Level Density Parameter in the Cascade-Exciton Model

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Chinese Physics Letters 2009年第2期26卷 90-93页

作者： zafar Yasin Physics Division PINSTECH P.O. Nilore Islamabad Pakistan

A new method is used to compute the fission cross sections in which a change of the ratio of the level density parameter in fission to neutron emission channels is taken into account with the change of the incident energy of the projectile. It is shown that fission cross sections induced by nucleons and pions depend on the ratio of the level density parameter in the fission and evaporation modes, i,e. af /an, respectively. We are unable to describe well the cross sections for fission without using this new method. The computed values exhibit reasonable agreement with the experimental data found in the literature across a wide range of beam energies.

关键词： sea surface nonliear interaction numerical method

A Mathematical Modeling of 3D Cubical Geometry Hypothetical Reservoir under the Effect of Nanoparticles Flow Rate,Porosity,and Relative Permeability

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Computer Modeling in Engineering & Sciences 2024年第11期141卷 1193-1211页

作者： Mudasar zafar Hamzah Sakidin Abida Hussain Loshini Thiruchelvam Mikhail Sheremet Iskandar Dzulkarnain Roslinda Nazar abdullah Al-Yaari Rizwan Safdar Department of Fundamental and Applied Sciences Universiti Teknologi PETRONASBandar Seri Iskandar32610Malaysia School of Mathematics Actuarial and Quantitative Studies(SOMAQS)Asia Pacific University of Technology and Innovation(APU)Kuala Lumpur57000Malaysia Center for Research in Enhanced Oil Recovery Universiti Teknologi PETRONASBandar Seri Iskandar32610Malaysia Department of Physical and Mathematical Sciences Faculty of ScienceUniversiti Tunku Abdul RahmanPerak31900Malaysia Laboratory on Convective Heat and Mass Transfer Tomsk State UniversityTomsk634050Russia Department of Mathematical Sciences Faculty of Science&TechnologyUniversiti Kebangsaan MalaysiaBangi43600Malaysia Henan Province International Collaboration Lab of Forest Resources Utilization School of ForestryHenan Agricultural UniversityZhengzhou450002China Higher Institution Centre of Excellence(HICoE) Institute of Tropical Aquaculture and Fisheries(AKUATROP)Universiti Malaysia TerengganuKuala Nerus21030Malaysia

This study aims to formulate a steady-state mathematical model for a three-dimensional permeable enclosure(cavity)to determine the oil extraction rate using three distinct nanoparticles,SiO_(2),Al_(2)O_(3),and Fe_(2)O_(3),in unconventional oil *** simulation is conducted for different parameters of volume fractions,porosities,and mass flow rates to determine the optimal oil *** impact of nanoparticles on relative permeability(kr)and water is also *** simulation process utilizes the finite volume ANSYS *** study results showed that when the mass flow rate at the inlet is low,oil recovery goes *** addition,they indicated that silicon nanoparticles are better at getting oil out of the ground(i.e.,oil reservoir)than Al_(2)O_(3)and Fe_(2)O_(3).Most oil can be extracted from SiO_(2),Al_(2)O_(3),and Fe_(2)O_(3)at a rate of 97.8%,96.5%,and 88%,respectively.

关键词： Unconventional reservoir cubical cavity oil recovery rate reservoir engineering mathematical modeling

Recent Advances to Enhance Nutritional Quality of Rice

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Rice science 2023年第6期30卷 523-536页

作者： Sundus zafar XU Jianlong School of Life Sciences Jiangsu UniversityZhenjiang 212013China Shenzhen Branch Guangdong Laboratory for Lingnan Modern AgricultureAgricultural Genomics Institute at ShenzhenChinese Academy of Agricultural SciencesShenzhen 518120China The National Key Facility for Crop Gene Resources and Genetic Improvement Institute of Crop SciencesChinese Academy of Agricultural SciencesBeijing 100081China

The nutritional quality of rice is a major concern,along with the need to enhance productivity to feed the continuously growing ***,there is a requirement to breed high-yielding rice varieties with improved nutritional quality that can help combat malnutrition,a global health ***,breeding approaches have played a significant role in increasing rice yield while enhancing its nutritional *** addition to traditional breeding techniques,other recent approaches,such as genetic engineering,gene editing,omics methods,and agronomic practices,must also be employed to meet the nutritional needs of the current *** this review,we offered detailed information on the development of nutritionally improved rice varieties through the enhancement of protein content,microand macronutrients,vitamins,and oil quality using genetic engineering *** also identified QTLs associated with amino acids,proteins,and micronutrients in ***,omics approaches provide a range of tools and techniques for effectively exploring resources and understanding the molecular mechanisms involved in trait *** branches,including transcriptomics,proteomics,ionomics,and metabolomics,are efficiently utilized for improving rice ***,by utilizing the information obtained from these techniques and incorporating all of these recent approaches,we can effectively modify the rice genome,directly enhancing the nutritional value of rice *** will help address the challenges of malnutrition in the years to come.

关键词： rice nutritional quality quantitative trait locus genetic engineering omics gene editing

Probing the intrinsic optical quality of CVD grown MoS2

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Nano Research 2017年第5期10卷 1608-1617页

作者： Amina zafar Haiyan Nan Zainab zafar Zhangting Wu Jie Jiang Yumeng You Zhenhua Ni Department of Physics and Key Laboratory of MEMS of the Ministry of Education Southeast University Nanjing 211189 China Ordered Matter Science Research Center Southeast University Nanjing 211189 China

Optical emission efficiency of two-dimensional layered transition metal dichalcogenides （TMDs） is one of the most important parameters affecting their optoelectronic performance. The optimization of the growth parameters by chemical vapor deposition （CVD） to achieve optoelectronic-grade quality TMDs is, therefore, highly desirable. Here, we present a systematic photoluminescence （PL） spectroscopic approach to assess the intrinsic optical and crystalline quality of CVD grown MoS2 （CVD MoS2）. We propose the use of the intensity ratio between the PL measured in air and vacuum as an effective way to monitor the intrinsic optical quality of CVD MoS2. Low-temperature PL measurements are also used to evaluate the structural defects in MoS2, via defect-associated bound exciton emission, which well correlates with the field-effect carrier mobility of MoS2 grown at different temperatures. This work therefore provides a sensitive, noninvasive method to characterize the optical properties of TMDs, allowing the tuning of the growth parameters for the development of optoelectronic devices.

关键词： transition metaldichalcogenides MoS2 chemical vapor deposition photoluminescence defect mobility

Link between COVID-19 vaccines and myocardial infarction

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World Journal of Clinical Cases 2022年第28期10卷 10109-10119页

作者： Umema zafar Hamna zafar Mian Saad Ahmed Madiha Khattak Department of Physiology Khyber Medical CollegePeshawar 25000Pakistan Department of Medicine Khyber Teaching HospitalPeshawar 25000Pakistan Department of Forensic Medicine Khyber Medical CollegePeshawar 25000Pakistan

BACKGROUND Vaccines for coronavirus disease 2019(COVID-19) include Ch Ad Ox1-SARS-COV-2(Astra Zeneca),***2.S(Janssen),m RNA-1273(Moderna),BNT162b2(Pfizer),BBIBP-Cor V(Sinopharm),Corona Vac(Sinovac),and Bharat Biotech BBV152(Covaxin).AIM To find the association between COVID-19 vaccines and myocardial infarction(MI).METHODS This is a systematic review that involved searching databases such as MEDLINE,EMBASE,and Pak Medi Net after making a search strategy using Me SH and Emtree *** criteria were set,and studies having no mention of MI as a complication of COVID-19 vaccination,protocols,genetic studies,and animal studies were *** was extracted using a predesigned extraction table,and 29 studies were selected after screening and applying the eligibility *** The majority of studies mentioned Astra Zeneca(18 studies) followed by Pfizer(14 studies) and Moderna(9 studies) in subjects reporting MI after *** of all the studies,69% reported MI cases after the first COVID-19 vaccination dose and 14% after the second,44% reported ST-segment elevation MI,and 26% reported non-ST-segment elevation *** mortality rate was 29% after *** In conclusion,many studies linked MI to COVID-19 vaccinations,but no definitive association could be found.

关键词： SARS-Co V-2 infection Vaccination Myocardial infarction Association Pfizer Astra Zeneca Moderna Sinovac Janssen Covaxin

A U-Net-Based CNN Model for Detection and Segmentation of Brain Tumor

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Computers, Materials & Continua 2023年第1期74卷 1333-1349页

作者： Rehana Ghulam Sammar Fatima Tariq Ali Nazir Ahmad zafar abdullah A.Asiri Hassan A.Alshamrani Samar M.Alqhtani Khlood M.Mehdar Department of Computer Science COMSATS University IslamabadSahiwal CampusSahiwal57000Pakistan Radiological Sciences Department College of applied medical sciencesNajran UniversityNajran61441Saudi Arabia Department of Information Systems College of Computer Science and Information SystemsNajran UniversityNajran61441Saudi Arabia Anatomy Department Medicine CollegeNajran UniversityNajran61441Saudi Arabia

Human brain consists of millions of cells to control the overall structure of the human *** these cells start behaving abnormally,then brain tumors *** and initial stage brain tumor detection has always been an issue in the field of medicines for medical *** handle this issue,various deep learning techniques for brain tumor detection and segmentation techniques have been developed,which worked on different datasets to obtain fruitful results,but the problem still exists for the initial stage of detection of brain tumors to save human *** this purpose,we proposed a novel U-Net-based Convolutional Neural Network(CNN)technique to detect and segmentizes the brain tumor for Magnetic Resonance Imaging(MRI).Moreover,a 2-dimensional publicly available Multimodal Brain Tumor Image Segmentation(BRATS2020)dataset with 1840 MRI images of brain tumors has been used having an image size of 240×240 *** initial dataset preprocessing the proposed model is trained by dividing the dataset into three parts i.e.,testing,training,and validation *** model attained an accuracy value of 0.98%on the BRATS2020 dataset,which is the highest one as compared to the already existing techniques.

关键词： U-net brain tumor magnetic resonance images convolutional neural network segmentation

Comparison of Fission Induced by Protons and Pions

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Chinese Physics Letters 2011年第8期28卷 58-60页

作者： zafar Yasin M.Ikram Shahzad Physics Division PINSTECHP.O.NiloreIslamabadPakistan

We compare the properties of fission induced by protons and *** different methodologies are used to make this ***,it is shown that pion-induced fission cross sections are not much different in magnitude from proton-induced fission cross sections at the same beam kinetic ***,across the pion-nucleon(3,3)resonance so prominent with free nucleons,it has been observed that there is no significant change in the reaction mechanism in the case of ***,it is noted that an empirical expression used for evaluations of proton-induced fission cross sections is also valid for positive pion-induced fission cross sections,at least for actinide *** cross sections computed using a cascade-exciton model code for ^(209)Bi and ^(238)U are also compared with the experimental data available.

关键词： energy beam kinetic

An improved chaotic hybrid differential evolution for the short-term hydrothermal scheduling problem considering practical constraints

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Frontiers of Information Technology & Electronic Engineering 2015年第5期16卷 404-417页

作者： Tahir Nadeem MALIK Salman zafar Saaqib HAROON Electrical Engineering Department University of Engineering and Technology

Short-term hydrothermal scheduling(STHTS) is a non-linear and complex optimization problem with a set of operational hydraulic and thermal constraints. Earlier, this problem has been addressed by several classical techniques; however, due to limitations such as non-linearity and non-convexity in cost curves, artificial intelligence tools based techniques are being used to solve the STHTS problem. In this paper an improved chaotic hybrid differential evolution(ICHDE) algorithm is proposed to find an optimal solution to this problem taking into account practical constraints. A self-adjusted parameter setting is obtained in differential evolution(DE) with the application of chaos theory, and a chaotic hybridized local search mechanism is embedded in DE to effectively prevent it from premature convergence. Furthermore, heuristic constraint handling techniques without any penalty factor setting are adopted to handle the complex hydraulic and thermal constraints. The superiority and effectiveness of the developed methodology are evaluated by its application in two illustrated hydrothermal test systems taken from the literature. The transmission line losses, prohibited discharge zones of hydel plants, and ramp rate limits of thermal plants are also taken into account. The simulation results reveal that the proposed technique is competent to produce an encouraging solution as compared with other recently established evolutionary approaches.

关键词： Valve-point effect Prohibited discharge zones Differential evolution Chaotic sequences Constraint handling