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Forest mapping:a comparison between hyperspectral and multispectral images and technologies

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Journal of Forestry Research 2018年第5期29卷 1395-1405页

作者： mohamad m.Awad Remote Sensing Center National Council for Scientific Research

mapping forests is an important process in managing natural *** present,due to spectral resolution limitations,multispectral images do not give a complete separation between different forest *** contrast,advances in remote sensing technologies have provided hyperspectral tools and images as a solution for the determination of *** this study,spectral signatures for stone pine（Pinus pinea L.） forests were collected using an advanced spectroradiometer ＂ASD FieldSpec 4 Hi-Res＂ with an accuracy of 1 *** spectral signatures are used to compare between different multispectral and hyperspectral satellite *** comparison is based on processing satellite images： hyperspectral Hyperion,hyperspectral CHRIS-Proba,Advanced Land Imager（ALI）,and Landsat *** and classification methods for hyperspectral and multispectral images are investigated and *** addition,a well-known hyperspectral image classification algorithm,spectral angle mapper（SAm）,has been improved to perform the classification process efficiently based on collected spectral *** results show that the modified SAm is 9% more accurate than the conventional *** addition,experiments indicate that the CHRIS-Proba image is more accurate than Landsat 8（overall accuracy 82%,precision 93%,and Kappa coefficient 0.43 compared to 60,67%,and 0.035,respectively）.Similarly,Hyperion is better than ALI in mapping stone pine（overall accuracy 92%,precision 97%,and Kappa coefficient 0.74 compared to 52,56%,and -0.032,respectively）.

关键词： Classification economy Hyperspectral multispectral Spectral signatures Stone pine

electrical and dielectric properties of Na_(1/2)La_(1/2)Cu_3Ti_4O_(12) ceramics prepared by high energy ball-milling and conventional sintering

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Chinese Physics B 2016年第12期25卷 474-480页

作者： H mahfoz Kotb mohamad m Ahmad Department of Physics College of ScienceKing Faisal University Department of Physics Faculty of ScienceAssiut University

We report on the measurements of the electrical and dielectric properties of Na1/2La1/2Cu3Ti4O12 （NLCTO） ce- ramics prepared by high energy ball-milling and conventional sintering without any calcination steps. The x-ray powder diffraction analysis shows that pure perovskite-like CCTO phase is obtained after sintering at 1025 ℃-1075 ℃. Higher sintering temperatures result in multi-phase ceramics due to thermal decomposition. Scanning electron microscope observations reveal that the grain size is in a range of - 3 μm-5 μm for these ceramics. Impedance spectroscopy measurements performed in a wide frequency range （1 Hz-10 mHz） and at various temperatures （120 K-470 K） are used to study the dielectric and electrical properties of NLCTO ceramics. A good compromise between high ε′ （5.7 ×10^3 and 4.1 × 10^3 at 1.1 kHz and 96 kHz, respectively） and low tan δ （0.161 and 0.126 at 1.1 kHz and 96 kHz, respectively） is obtained for the ceramic sintered at 1050 ℃. The observed high dielectric constant behavior is explained in terms of the internal barrier layer capacitance effect.

关键词： ceramics sintering dielectric loss and relaxation electrical

An innovative intelligent system based on remote sensing and mathematical models for improving crop yield estimation

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Information Processing in Agriculture 2019年第3期6卷 316-325页

作者： mohamad m.Awad National Council for Scientific Research RemoteSensing CenterP.O.Box 11-8281BeirutLebanon

There are many crop yield estimation techniques which are used in countries around the world,but the most effective is the one based on remote sensing data and ***,remote sensing data which are needed to estimate crop yield is incomplete most of the time due to many obstacles such as climate conditions(percentage of cloud cover),and low temporal *** problems reduce the effectiveness of the known crop yield estimation techniques and render them *** was many attempts to solve these problems by using high temporal resolution and low spatial resolution ***,this type of images are suitable for very large homogeneous crop *** compensate for the lack of high spatial resolution satellite images,a new mathematical model is *** on the new mathematical model an intelligent system is implemented that includes the use of energy balance equation to improve the crop yield *** verify the results of the intelligent system,several farmers are interviewed and information about their crops yield is *** comparison between the estimated crop yield and the actual production in different fields proves the high accuracy of the intelligent system.

关键词： Crop yield environment Remote sensing Image processing evapotranspiration Intelligent system

Risk profiling in patients undergoing penile prosthesis implantation

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Asian Journal of Andrology 2020年第1期22卷 8-14页

作者： Linda m Huynh mohamad m Osman Faysal A Yafi Department of Urology University of CaliforniaIrvine Medical CenterOrangeCA 92868USA

Penile prosthesis implantation is the gold standard of surgical therapy for patients with medication-refractory erectile ***,this umbrella definition includes significant heterogeneity and associated risk profiles that should be candidly discussed and addressed *** associated with operative success and patient satisfaction are often surgery specific;however,risk profiling via patient selection,preoperative optimization,proper device selection,and intraoperative consideration are highly *** examples of common risk profiles include comorbidity(ies)such as cardiovascular disease,diabetes mellitus,prior abdominal surgery,Peyronie's disease,and psychological risk ***,integration of surgeon-and patient-amenable characteristics is key to decreasing risk of infection,complication,and need for ***,patient risk profiling provides a unique context for proper device selection and evidence-based intraoperative considerations.

关键词： patient selection penile prosthesis risk factors

COVID-19:cardiovascular manifestations-a review of the cardiac effects

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Journal of Geriatric Cardiology 2022年第3期19卷 245-250页

作者： Taha Hatab mohamad Bahij moumneh Abdul Rahman Akkawi mohamad Ghazal Samir e.Alam marwan m.Refaat Department of Internal medicine Division of CardiologyAmerican University of Beirut Medical CenterBeirutLebanon

The coronavirus first reported in China in November 2002 in the form of atypical pneumonia known as the severe acute respiratory syndrome (SARS).[1] The virus then appeared in 2012 in Saudi Arabia as the middle east respiratory syndrome (meRS).[2] The year 2020 witnessed a novel β-coronavirus related to the previous detected viruses.[3] It was the severe acute respiratory syndrome coronavirus 2 (SARS-Co V-2)-a positive single stranded RNA virus.

关键词： acute cardiac respiratory

Lattice Boltzmann simulation of natural convection in open end cavity with inclined hot wall

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Applied mathematics and mechanics(english edition) 2015年第4期36卷 523-540页

作者： m.NAZARI H.SHOKRI A.A.mohamad Department of mechanical engineering Shahrood University of Technology Department of mechanical engineering Schulich School of EngineeringCentre for Environmental Engineering for Research and EducationUniversity of Calgary

Natural convection in an open end cavity with a hot inclined wall is simulated based on the lattice Boltzmann method （LBm）. The physics of flow and energy transfer in open end cavities are addressed when the hot wall is inclined. The combination of the two topics （open cavity and inclined walls） is the main novelty of the present study. The effects of the angle of the hot inclined wall on the flow field and heat transfer are thoroughly investigated. The Prandtl number is fixed to 0.71 （air）. The Rayleigh number and the angle of the hot inclined wall are varied in the range of 10^4 to 10^6 and 60° to 85°, respectively. The results are presented for two different aspect ratios, i.e., A = 1 and 2. The results obtained with the LBm are also compared with those of the finite volume method （FVm）. The predicted results of the LBm conform to those of the FVm. The results show that by increasing the angle of the hot inclined wall and the aspect ratio of the cavity, the average Nusselt number decreases. The trend of the local Nusselt number on the inclined wall is also discussed.

关键词： lattice Boltzmann method (LBm) natural convection open end cavity,inclined wall

Feasibility of Solar Tracking System for PV Panel in Sunbelt Region

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Journal of modern Power Systems and Clean energy 2021年第2期9卷 395-403页

作者： Soulayman Soulayman mohamad Hamoud mohamad-Amir Hababa Wassim Sabbagh the Department of Applied Physics Higher Institute for Applied Sciences and TechnologyDamascusP O Box 31983Syria

In the study of the feasibility of solar tracking systems for crystalline silicon photovoltaic(PV)panels in hot and cold regions,it is argued recently that a tracking system is not necessary for sunbelt countries owing to the overheating that results from excessive exposure to solar *** conclusion has been formulated based on a mathematical model,which in turn is based on the assumption that the PV module temperature can be calculated using an empirical relation of this temperature to ambient temperature,available solar irradiance,and nominal operation cell temperature(NOCT).To support this conclusion,it is claimed that the mathematical model is validated ***,this assumption is vague and widely used in the *** objective of the present work is to reevaluate the above-mentioned assumption and to discuss the results deriving from *** is shown experimentally in the present work that the above-mentioned assumption overestimates the PV module *** a solar irradiance of 900 W/m2,ambient temperature of 25℃,and wind speed of 5 m/s,the measured PV module temperature is lower than the value calculated based on the mentioned assumption by 29.26%.

关键词： Photovoltaic(PV)module temperature wind speed influence PV module efficiency experimental verification Damascus clear-sky conditions

The sexually dimorphic expression of glutamate transporters and their implication in pain after spinal cord injury

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Neural Regeneration Research 2025年第11期20卷 3317-3329页

作者： Jennifer m.Colón-mercado Aranza I.Torrado-Tapias Iris K.Salgado Jose m.Santiago Samuel e.Ocasio Rivera Dina P.Bracho-Rincon Luis H.Pagan Rivera Jorge D.miranda Department of Physiology University of Puerto RicoMedical Sciences CampusSan JuanPRUSA National Institutes of Health National Human Genome Research InstituteBethesdaMDUSA Universidad Central del Caribe School of MedicineBayamónPRUSA University of Puerto Rico Carolina CampusCarolinaPRUSA Institute of Neurobiology San JuanPRUSA

In addition to the loss of motor function,~60% of patients develop pain after spinal cord *** cellular-molecular mechanisms are not well understood,but the data suggests that plasticity within the rostral,epicenter,and caudal penumbra of the injury site initiates a cellularmolecular interplay that acts as a rewiring mechanism leading to central neuropathic *** can lead to the formation of new connections triggering abnormal sensory *** excitatory glutamate transporters are responsible for the reuptake of extracellular glutamate which makes them a critical target to prevent neuronal hyperexcitability and *** previous studies showed a sexually dimorphic therapeutic window for spinal cord injury after treatment with the selective estrogen receptor modulator *** this study,we investigated the anti-allodynic effects of tamoxifen in male and female rats with spinal cord *** hypothesized that tamoxifen exerts anti-allodynic effects by increasing the expression of glutamate transporters,leading to reduced hyperexcitability of the secondary neuron or by decreasing aberrant *** and female rats received a moderate contusion to the thoracic spinal cord followed by subcutaneous slow-release treatment of tamoxifen or matrix pellets as a control(placebo).We used von Frey monofilaments and the“up-down method”to evaluate mechanical *** treatment decreased allodynia only in female rats with spinal cord injury revealing a sexdependent *** expression profile of glutamatergic transporters(excitatory amino acid transporter 1/glutamate aspartate transporter and excitatory amino acid transporter 2/glutamate transporter-1)revealed a sexual dimorphism in the rostral,epicenter,and caudal areas of the spinal cord with a pattern of expression primarily on *** rodents showed a significantly higher level of excitatory amino acid transporter-1 expression while male rodents showed increased

关键词： allodynia central neuropathic pain eAAT-1/GLAST eAAT-2/GLT-1 glutamate transporters selective estrogen receptor modulator sexual dimorphism spinal cord injury trauma

early therapeutic effect of platelet-rich fibrin combined with allogeneic bone marrow-derived stem cells on rats’ critical-sized mandibular defects

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World Journal of Stem Cells 2020年第1期12卷 55-69页

作者： muhammad A Awadeen Fouad A Al-Belasy Laila e Ameen mohamad e Helal mohammed e Grawish Department of Oral Biology Faculty of Oral and Dental MedicineDelta University for Science and TechnologyMansoura 11152Egypt Department of Oral Surgery and Anesthesia Faculty of Oral and Dental MedicineDelta University for Science and TechnologyMansoura 11152Egypt Department of Oral Biology Faculty of DentistryMansoura UniversityMansoura 35516Egypt

BACKGROUND Critically sized bone defects represent a significant challenge to orthopaedic surgeons *** defects generally result from severe trauma or resection of a whole large *** bone grafts are the current gold standard for the reconstruction of such ***,due to increased patient morbidity and the need for a second operative site,other lines of treatment should be *** find alternative unconventional therapies to manage such defects,bone tissue engineering using a combination of suitable bioactive factors,cells,and biocompatible scaffolds offers a promising new approach for bone *** To evaluate the healing capacity of platelet-rich fibrin(PRF)membranes seeded with allogeneic mesenchymal bone marrow-derived stem cells(BmSCs)on critically sized mandibular defects in a rat *** Sixty-three Sprague Dawley rats were subjected to bilateral bone defects of critical size in the mandibles created by a 5-mm diameter trephine *** were allocated to three equal groups of 21 rats *** I bone defects were irrigated with normal saline and designed as negative *** of group II were grafted with PRF membranes and served as positive controls,while defects of group III were grafted with PRF membranes seeded with allogeneic *** rats from each group were killed at 1,2 and 4 *** mandibles were dissected and prepared for routine haematoxylin and eosin(He)staining,masson's trichrome staining and CD68 immunohistochemical *** Four weeks postoperatively,the percentage area of newly formed bone was significantly higher in group III(0.88±0.02)than in groups I(0.02±0.00)and II(0.60±0.02).The amount of granulation tissue formation was lower in group III(0.12±0.02)than in groups I(0.20±0.02)and II(0.40±0.02).The number of inflammatory cells was lower in group III(0.29±0.03)than in groups I(4.82±0.08)and II(3.09±0.07).CONCLUSION Bone regenerative quality of critically sized mandibula

关键词： Platelet-rich fibrin membrane Bone marrow-derived stem cells Critical-sized mandibular defects Rats Histological and immunohistochemical staining