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Consecutive narrow and broad quasi-periodic fast-propagating wave trains associated with a flare

Science China(Physics,Mechanics & Astronomy) 2024年第5期67卷 200-211页

作者： Xinping Zhou Yuandeng Shen Chengrui Zhou Zehao Tang ahmed ahmed Ibrahim College of Physics and Electronic Engineering Sichuan Normal UniversityChengdu 610068China State Key Laboratory of Space Weather Chinese Academy of SciencesBeijing 100190China Yunnan Observatories Chinese Academy of SciencesKunming 650216China Department of Physics and Astronomy College of ScienceKing Saud UniversityP.O.Box 2455Riyadh 11451Saudi Arabia

The excitation mechanism of coronal quasi-period fast-propagating(QFP)wave trains remains *** Atmospheric Imaging Assembly onboard the Solar Dynamics Observatory observations,we study a narrow and a broad QFP wave trains excited one after another during the successive eruptions of filaments hosted within a fan-spine magnetic system on October 20,*** consecutive occurrence of these two types of QFP wave trains in the same event provides an excellent opportunity to explore their excitation mechanisms and compare their physical *** observational results reveal that narrow and broad QFP wave trains exhibit distinct speeds,periods,energy fluxes,and relative intensity amplitudes,although originating from the same active region and being associated with the same GOES C2.9 *** wavelet analysis,we find that the narrow QFP wave train shares a similar period with the flare itself,suggesting its possible excitation through the pulsed energy release in the magnetic reconnection process that generated the accompanying *** the other hand,the broad QFP wave train appears to be associated with the energy pulses released by the successive expansion and unwinding of filament ***,it is plausible that the broad QFP wave train was also excited by the sequential stretching of closed magnetic field lines driven by the erupting *** findings shed light on the different excitation mechanisms and origins of the QFP wave trains.

关键词： narrow wave excitation

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Sero-Prevalence and Risk factors of Contagious Bovine Pleuropneumonia (CBPP) in Afgoye District Lower Shabelle Region, Somalia

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Open Journal of Veterinary Medicine 2024年第2期14卷 11-20页

作者： ahmed Mohamed ahmed Sumaya Hassan Ali Abdisalam Mohamed Ali Abdirazack Saleban Osman Binti Abubakar Mohamed Abdifatah Mohamud Ibar Shafii Abdullahi Mohamed Mohamed Abdelrahman Mohamed ahmed Ali Omar Zakaria Ibrahim Issack College of Veterinary Medicine Abrar University Mogadishu Somalia Faculty of Veterinary Medicine and Animal Husbandry Somali National University Mogadishu Somalia Faculty of Veterinary Science Benadir University Mogadishu Somalia

Contagious bovine Pleuropneumonia (CBPP) is an infectious and highly contagious respiratory disease of cattle and water buffalo, caused by the Mycoplasma mycoides subspecies mycoides. It induces significant economic losses and leads to a severe livestock production problem, negatively influencing people’s livelihoods of affected countries. In Somalia, there is no updated data on the prevalence and distribution of the disease. Hence, a descriptive cross-sectional study was conducted from September 2022 to June 2023 in different villages under the Afgoye District of lower Shabelle region, Somalia. The main purpose of this study is to assess the sero-prevalence and identify the associated risk factors for the occurrence of the disease. In this study, villages, age, sex, breed, and body condition were considered as risk factors. A total of 90 blood samples were collected and tested in the laboratory using the Anti-CBPP Elisa kit test. Out of 90 serum samples from herd cattle, 32 were positive, resulting in an overall prevalence of 35.5%. In addition, we found a statistically significant variation between the prevalence of the disease and factors such as sex, age, body condition and breeds. In summary, the overall prevalence of Contagious bovine pleuropneumonia in this study area is worth to be considered because there is a low quality of health care and less awareness of the Contagious bovine Pleuropneumonia effects on herds, which warrants the official authorities to act and follow appropriate preventive and control measures to reduce the incidence of the disease and generate appropriate controlling and prevention measures in all regions of Somalia.

关键词： Contagious Bovine Pleuropneumonia Sero-Prevalence Cattle Somalia Mycoplasma Cross Sectional Study

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Magnetoresistive properties of Ni-doped La_(0.7)Sr_(0.3)MnO_3 manganites

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Rare Metals 2016年第7期35卷 551-558页

作者： ahmed Mohamed ahmed Abd El-Moez ahmed Mohamed Medhat Abdelrady Abdellateef Hassan ahmed Abd El-Ghanny Physics Department Faculty of ScienceSohag University

Lao.7Sr0.3Mnl_xNixO3 （x = 0, 0.025, 0.050 and 0.075） ceramics were prepared by the conventional solid-state reaction method. The partial substitution of Mn by Ni2＋ leads to a decrease in cell volume as well as a structural transition from the rhombohedral to the orthorhombic structure. Ni2＋ doping increases the electrical resistivity, decreases the semiconductor-metal transition temperature （Tms） and relatively enhances the room temperature magnetoresistance （MR）, especially in x = 0.025 and around Tins. With respect to conduction mechanism, the small polaron hopping （SPH） and the variable range hopping （VRH） models were used to ex- amine conduction in the semiconducting region.

关键词： Manganites X-ray diffraction Structure Electrical resistivity Magnetoresistance

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Conservation Laws for Partially Conservative Variable Mass Systems via d＇Alembert＇s Principle

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Chinese Physics Letters 2008年第9期25卷 3181-3184页

作者： AFTAB ahmed NASEER ahmed QUDRAT Khan Department of Mathematics Quaid-I-Azam University 45320 Islamabad 44000 Pakistan

Conservation laws for partially conservative variable mass dynamical systems under symmetric infinitesimal transformations are determined. A generalization of Lagrange-d ＇Alembert＇s principle for a variable mass system in terms of asynchronous virtual variation is presented. The generalized Killing equations are obtained such that their solution yields the transformations and the associated conservation laws. An example illusstrative of the theory is furnished at the end as well.

关键词： the power-law exponents precipitation durative abrupt precipitation change

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SOME PROPERTIES OF m-ISOMETRIES AND m-INVERTIBLE OPERATORS ON BANACH SPACES

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Acta Mathematica Scientia 2012年第2期32卷 520-530页

作者： Ould ahmed Mahmoud Sid ahmed Department of Mathematics College of ScienceAljouf UniversityAljouf 2014Saudi Arabia

This article has two purposes： the first is to give some structure results for the class of m-isometries, and the second purpose is to extend the notions of left and right inverses to m-left and m-right inverses resp... 详细信息

关键词： m-isometry m-left inverse m-right inverse approximate spectrum pointspectrum

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Patch-based vehicle logo detection with patch intensity and weight matrix

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Journal of Central South University 2015年第12期22卷 4679-4686页

作者：刘海明黄樟灿 ahmed Mahgoub ahmed Talab School of Science Wuhan University of Technology College of Engineering Elimam ELMahdi University

A patch-based method for detecting vehicle logos using prior knowledge is *** representing the coarse region of the logo with the weight matrix of patch intensity and position,the proposed method is robust to bad and complex environmental *** bounding-box of the logo is extracted by a thershloding *** results show that 93.58% location accuracy is achieved with 1100 images under various environmental conditions,indicating that the proposed method is effective and suitable for the location of vehicle logo in practical applications.

关键词： vehicle logo detection prior knowledge gradient extraction patch intensity weight matrix background removing

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Impacts of climate change on water quantity, water salinity, food security, and socioeconomy in Egypt

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Water Science and Engineering 2021年第1期14卷 17-27页

作者： Mohie El Din Mohamed Omar ahmed Moustafa ahmed Moussa Reinhard Hinkelmann National Water Research Center Fum Ismailiya CanalShoubra El-Kheima 13411Egypt International Center for Agricultural Research in the Dry Areas Cairo 2416Egypt Nile Research Institute(NRI) National Water Research CenterEl-Qanater 13621Egypt Department of Water Engineering Technische Universit€at Berlin(TU Berlin)Campus El GounaEl Gouna 84513Egypt

Climate change might have direct impacts on water quantity in Egypt and lead to indirect effects on Mediterranean saltwater intrusion to groundwater,which exposes agriculture to *** study investigated impacts of climate change on agriculture,with particular regard to food security and socioeconomy,and quantified the effectiveness of cropping pattern adaptation measures by integrating three mathematical *** BlueM model was used for hydrological simulations of Nasser Lake under flooding scenarios to predict the water supply from the High Aswan *** water and salinity balance(WB-SAL)model was adopted to estimate the water salinity in the Nile *** simulated results from the BlueM and WB-SAL models were integrated with the agricultural simulation model for Egypt(ASME)to project cropping patterns,food security,and socioeconomy throughout the *** results showed that future climate change will directly affect the total crop area;crop areas for 13 crop types;the self-sufficiency of wheat,rice,cereal,and maize supplies;and socioeconomic *** proposed cropping pattern adaptation measures focus on fixing the crop areas of rice and orchards and providing half of the population with lentils,maize,onion,vegetables,milk,and *** adaptation measures have the potential to promote food security without causing deterioration of the socioeconomic ***,water availability has much more significant effects on food security and socioeconomy than cropping pattern adaptation measures ***,the country should rationalize water use efficiency and increase water supply.©2021 Hohai *** and hosting by Elsevier *** is an open access article under the CC BY-NC-ND license(http://***/licenses/by-nc-nd/4.0/).

关键词： Climate change Water quantity Salinity Cropping pattern adaptation measures Food security Socioeconomy

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Improved Hybrid Swarm Intelligence for Optimizing the Energy in WSN

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Computer Systems Science & Engineering 2023年第8期46卷 2527-2542页

作者： ahmed Najat ahmed JinHyung Kim Yunyoung Nam Mohamed Abouhawwash Department of Computer Engineering Lebanese French UniversityErbil44001Iraq B LIFE Inc. Suwon16463Korea Department of ICT Convergence Soonchunhyang UniversityAsan31538Korea Department of Mathematics Faculty of ScienceMansoura UniversityMansoura35516Egypt Department of Computational Mathematics Scienceand Engineering(CMSE)Michigan State UniversityEast LansingMI48824USA

In this current century,most industries are moving towards automation,where human intervention is dramatically *** revolution leads to industrial revolution 4.0,which uses the Internet of Things(IoT)and wireless sensor networks(WSN).With its associated applications,this IoT device is used to compute the receivedWSN data from devices and transfer it to remote locations for *** general,WSNs,the gateways are a long distance from the base station(BS)and are communicated through the gateways nearer to the *** the gateway,which is closer to the BS,energy drains faster because of the heavy load,which leads to energy issues around the *** the sensors are battery-operated,either replacement or recharging of those sensor node batteries is not possible after it is deployed to their corresponding *** that situation,energy plays a vital role in sensor *** reducing the network energy consumption and increasing the network lifetime,this paper proposed an efficient cluster head selection using Improved Social spider Optimization with a Rough Set(ISSRS)and routing path selection to reduce the network load using the Improved Grey wolf optimization(IGWO)approach.(i)Using ISSRS,the initial clusters are formed with the local nodes,and the cluster head is chosen.(ii)Load balancing through routing path selection using *** simulation results prove that the proposed optimization-based approaches efficiently reduce the energy through load balancing compared to existing systems in terms of energy efficiency,packet delivery ratio,network throughput,and packet loss percentage.

关键词： Wireless sensor networks(WSN) internet of things(IoT) energy efficiency load balance sensors grey wolf optimization social spider optimization

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Mobile Fog Computing by Using SDN/NFV on 5G Edge Nodes

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Computer Systems Science & Engineering 2022年第5期41卷 751-765页

作者： G.R.Sreekanth S.ahmed Najat ahmed Marko Sarac Ivana Strumberger Nebojsa Bacanin Miodrag Zivkovic Department of Computer Science and Engineering Kongu Engineering CollegeErode638060India Department of Computer Engineering Lebanese French UniversityErbil44001Iraq Singidunum University Belgrade11000Serbia

Abstract:Fog computing provides quality of service for cloud *** the data computation intensifies,edge computing becomes ***,mobile fog computing is used for reducing traffic and the time for data computation in the *** previous studies,software-defined networking(SDN)and network functions virtualization(NFV)were used separately in edge *** industrial and academic research is tackling to integrate SDN and NFV in different environments to address the challenges in performance,reliability,and ***/NFV is still in *** traditional Internet of things(IoT)data analysis system is only based on a linear and time-variant system that needs an IoT data system with a high-precision *** paper proposes a combined architecture of SDN and NFV on an edge node server for IoT devices to reduce the computational complexity in cloud-based fog *** provides a generalization structure of the forwarding plane,which is separated from the control ***,NFV concentrates on virtualization by combining the forwarding model with virtual network functions(VNFs)as a single or chain of VNFs,which leads to interoperability and *** orchestrator layer in the proposed software-defined NFV is responsible for handling real-time tasks by using an edge node server through the SDN controller via four actions:task creation,modification,operation,and *** proposed architecture is simulated on the EstiNet simulator,and total time delay,reliability,and satisfaction are used as evaluation *** simulation results are compared with the results of existing architectures,such as software-defined unified virtual monitoring function and ASTP,to analyze the performance of the proposed *** analysis results indicate that our proposed architecture achieves better performance in terms of total time delay(1800 s for 200 IoT devices),reliability(90%),and satisfaction(90%).

关键词： Mobile fog computing edge computing edge node IoT softwaredefined networking network functions virtualization orchestrator

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Sudden death in the southern region of Saudi Arabia:A retrospective study

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World Journal of Clinical Cases 2023年第20期11卷 4843-4851页

作者： ahmed Mohamed ahmed Al-Emam Abdulrahman Dajam Mohammed Alrajhi Waleed Alfaifi Mubarak Al-Shraim ahmed Mohamed Helaly Department of Pathology College of MedicineKing Khalid UniversityAsir 61421Saudi Arabia Forensic Medicine and Clinical Toxicology Mansoura UniversityMansoura 35516Egypt Medical School King Khalid UniversityAsir 61421Saudi Arabia Clinical Science Faculty of MedicineYarmouk UniversityIrbid 21163Jordan

BACKGROUND Sudden death is unanticipated,non-violent death taking place within the first 24 h after the onset of *** is a major public health problem ***,the effects of living at moderate altitude on mortality are poorly *** To retrospectively report the frequency and the main causes of sudden deaths in relation to total deaths at Asir Central Hospital,2255 m above sea level,in the southern region of Saudi Arabia over a period of 4 years from 2013 to *** The medical records of 1821 deaths were examined and showed 353 cases(19.4%)of sudden *** The highest incidence of sudden death was among the elderly(51%),whereas,the lowest was among children and adolescents(6.5%).With regard to gender,the incidence of sudden death was higher in males(54.4%)compared to 45.6% in *** this study,we found that the most common direct causes of sudden death were cardiovascular diseases(29.2%),respiratory disease(22.7%),infectious disease(12.2%),cancer(9.4%)and hematological diseases(6.2%).With respect to seasonal variation,the highest incidence was during winter(31.32%)followed by summer(25.8%).CONCLUSION The results of this study will help emergency physicians and health care providers to exercise due care to reduce the incidence of sudden death and raise public awareness about the impact of sudden death.

关键词： Sudden death High altitude Cardiovascular Gender distribution Age Seasonal variation

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