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Performance of beacon safety message dissemination in Vehicular Ad hoc NETworks (VANETs)

Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第12期8卷 1990-2004页

作者： YOUSEFI Saleh FATHY mahmood BENSLIMANE Abderrahim Computer Engineering Faculty Iran University of Science and TechnologyNarmak Tehran 16846-13114 Tehran Iran Laboratoire d'Informatique d'Avignon LIA 339 chemin des Meinajaries BP 1228-84911 Avignon cedex 9 France

Currently, there is a growing belief that putting an IEEE 802.11-like radio into road vehicles can help the drivers to travel more safely. Message dissemination protocols are primordial for safety vehicular applications. There are two types of safety messages which may be exchanged between vehicles: alarm and beacon. In this paper we investigate the feasibility of deploying safety applications based on beacon message dissemination through extensive simulation study and pay special attention to the safety requirements. Vehicles are supposed to issue these messages periodically to announce to other vehicles their current situation and use received messages for preventing possible unsafe situations. We evaluate the performance of a single-hop dissemination protocol while taking into account the quality of service (QoS) metrics like delivery rate and delay. We realize that reliability is the main concern in beacon message dissemination. Thus, a new metric named effective range is defined which gives us more accurate facility for evaluating QoS in safety applications specifically. Then, in order to improve the performance, the effects of three parameters including vehicle's transmission range, message transmission's interval time and message payload size are studied. Due to special characteristics of the safety applications, we model the relationship between communication-level QoS and application-level QoS and evaluate them for different classes of safety applications. As a conclusion, the current technology of IEEE 802.11 MAC layer has still some challenges for automatic safety applications but it can provide acceptable QoS to driver assistance safety applications.

关键词： Safety applications Inter-vehicle communications Vehicular Ad hoc NETworks (VANETs) Application level QoS Effective range

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Studies on batch adsorptive removal of cadmium and nickel from synthetic waste water using silty clay originated from Balochistan-Pakistan

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Chinese Journal of Chemical Engineering 2020年第4期28卷 1171-1176页

作者： Abdul Samad Muhammad Imran Din mahmood Ahmed Institute of Chemistry University of the PunjabLahore 54590Pakistan Renacon Pharma Limited Lahore 54600Pakistan

The potentials of silty clay(SC),acquired from Chaman,Balochistan,were investigated as adsorbent for Ni(Ⅱ)and Cd(Ⅱ)removal from contaminated *** influence of different operating factors like dose,pH,temperature,and time of contact was explored,and optimum values were noted under batch adsorption *** study was conducted with varying concentrations of solutions on optimized conditions and different adsorption models i.e.,Langmuir,Freundlich,Temkin and Dubinin-Radushkevich(D-R)isotherm,which were employed to interpret the *** isothermal data of both Ni(Ⅱ)and Cd(Ⅱ)were well fitted to Langmuir isotherm suggesting the formation of monolayer of metal ions on silty *** values of adsorption capacity noted for Ni(Ⅱ)and Cd(Ⅱ)were 3.603 mg·g^-1 and 5.480 mg·g^-1,*** studies affirmed that pseudo second order(PSO)kinetics was being obeyed by the removal of Ni(Ⅱ)and Cd(Ⅱ).Thermodynamic variables like free energy change(ΔG°),enthalpy change(ΔH°)and entropy change(ΔS°)were *** negative value ofΔG°and the positive values ofΔH°andΔS°unfolded that the removal process of both metal ions of by SC was spontaneous,endothermic and feasible.

关键词： Adsorption Kinetics Isotherm Toxicity Silty clay Thermodynamics

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Dietary fiber and chicken microbiome interaction:Where will it lead to?

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Animal Nutrition 2020年第1期6卷 1-8页

作者： Tahir mahmood Yuming Guo State Key Laboratory of Animal Nutrition College of Animal Science and TechnologyChina Agricultural UniversityBeijing100193China

The last few decades have been marked by a rapid genetic improvement in chicken growth *** modern-day chicken is more efficient in converting feed into muscle mass than their *** enhanced efficiency emanates from better nutrient digestion,absorption,and *** gut has therefore become a research focus especially after the ban on the use of antibiotics as growth promoters(AGP)in *** pursuance of better gut health in the post-AGP era,many different strategies are being continuously sought and *** gut is inhabited by more than 900 bacterial species along with fungi and archaea,and they play an important role to maintain a conducive milieu for the host,A beneficial shift in the microbial ecosystem of the chicken can be promoted by many dietary and nondietary interventions,however,diet is ranked as one of the most important and potent regulators of gut microbiota ***,the constituents of the diet warrant special attention in the modulation of the gut *** dietary constituents,fiber possesses a significant ability to modulate the *** this review,we will highlight the importance of fiber in poultry nutrition and will also discuss the effects of fiber on gut microbiota and its resultant ramifications on the liver and brain.

关键词： Poultry Microbiota Gut health Antibiotic alternatives

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The Release Behavior,Biocompatibility and Physical Properties of Aid-loaded Strontium Doped Calcium Phosphate Cement

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Journal of Bionic Engineering 2020年第6期17卷 1209-1223页

作者： Maryam Mohammadi Sayed mahmood Rabiee Saeed Hesaraki Department of Materials Engineering Babol Noshirvani University of TechmologyBabol 71167-47148Iran Nanotechnologv and Advanced Materials Materials and Energy Research CenterKaraj ***AlborzIran

The effect of concurrent attendance of two inhibitors of bone degradation,namely Alendronate(Aid)sodium trihydrate and Strontium(Sr),on Calcium Phosphate Cement(CPC)characteristics was *** this aim,5 wt%Strontium and 21 mM Alendronate sodium trihydrate were used in calcium phosphate cement and setting time,ion and drug release were ***264.7 and G cell were cultured on cement samples and Tartrate-Resistant Acid Phosphatase(TRAP),Alkaline phosphatase(ALP)activity and MTT assay were *** results of structural analysis indicated that 21 mM Aid did not let the cement ***,colloidal silica was added to the cement formula and successfully decreased the setting *** vitro tests showed Sr-loaded sample had a greater inhibitory effect on biocompatibility of G cells than Aid-loaded and Sr-Ald-loaded *** addition,the findings about osteoblast MTT and ALP activity indicated that Sr was more effective in osteogenic activity of G *** simultaneous presence of Aid and Sr in Calcium Phosphate Cement(CPC)was not as effective in its biocompatibility as the presence of Sr alone.

关键词： calcium phosphate cements drug release alendronate sodium trihydrate strontium RAW264.7 cell G cell

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High throughput screening of localised and general corrosion in type 2205 duplex stainless steel at ambient temperature

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International Journal of Minerals,Metallurgy and Materials 2023年第12期30卷 2375-2385页

作者： Yiqi Zhou Sultan mahmood Dirk Lars Engelberg Beijing Advanced Innovation Center for Materials Genome Engineering Institute for Advanced Materials and TechnologyUniversity of Science and Technology BeijingBeijing 100083China Metallurgy and Corrosion School of MaterialsThe University of ManchesterM139PLManchesterUK Materials Performance Centre The University of ManchesterM139PLManchesterUK

Bipolar electrochemistry is used to produce a linear potential gradient across a bipolar electrode(BPE),providing direct access to the anodic and cathodic reactions under a wide range of applied *** occurrence of pitting corrosion,crevice corrosion,and general corrosion on type 2205 duplex stainless steel(DSS 2205)BPE has been observed at room *** critical pit depth of 10-20μm with a55%-75% probability of pits developing into stable pits at potential from+0.9 to+1.2 V ***(open circuit potential)are *** pit nucleation sites are either within ferritic grains or at the interface between austenite and *** critical conditions for pitting and crevice corrosion are discussed with Epit(critical pitting potential)and Ecre(critical crevice potential)decreasing from 0.87 and 0.80 V *** after150 s of exposure to 0.84 and 0.76 V *** after 900 s of exposure,*** growth kinetics under different applied bipolar potentials and exposure times have been *** ferrite is shown to be more susceptible to general dissolution.

关键词： bipolar electrochemistry duplex stainless steel pitting corrosion pit growth factor crevice corrosion

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Defocus Blur Segmentation Using Local Binary Patterns with Adaptive Threshold

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Computers, Materials & Continua 2022年第4期71卷 1597-1611页

作者： Usman Ali Muhammad Tariq mahmood Future Convergence Engineering School of Computer Science and EngineeringKorea University of Technology and Education1600Chungjeol-roByeongcheon-myeonCheonan31253Korea

Enormousmethods have been proposed for the detection and segmentation of blur and non-blur regions of the *** to the limited available information about blur type,scenario and the level of blurriness,detection and segmentation is a challenging ***,the performance of the blur measure operator is an essential factor and needs improvement to attain *** this paper,we propose an effective blur measure based on local binary pattern(LBP)with adaptive threshold for blur *** sharpness metric developed based on LBP used a fixed threshold irrespective of the type and level of blur,that may not be suitable for images with variations in imaging conditions,blur amount and ***,the proposed measure uses an adaptive threshold for each input image based on the image and blur properties to generate improved sharpness *** adaptive threshold is computed based on the model learned through support vector machine(SVM).The performance of the proposed method is evaluated using two different datasets and is compared with five state-of-the-art *** analysis reveals that the proposed method performs significantly better qualitatively and quantitatively against all of the compared methods.

关键词： Adaptive threshold blur measure defocus blur segmentation local binary pattern support vector machine

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Adaptive Deep Learning Model to Enhance Smart Greenhouse Agriculture

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Computers, Materials & Continua 2023年第11期77卷 2545-2564页

作者： Medhat A.Tawfeek Nacim Yanes Leila Jamel Ghadah Aldehim mahmood A.mahmood Department of Computer Science College of Computer and Information SciencesJouf UniversityP.O.Box 72314SkakaSaudi Arabia Department of Computer Science Faculty of Computers and InformationMenoufia UniversityP.O.Box 6121890MenoufiaEgypt Department of Software Engineering College of Computer and Information SciencesJouf UniversityP.O.Box 72314SkakaSaudi Arabia RIADI Laboratory La Manouba UniversityP.O.Box2010ManoubaTunisia Department of Information Systems College of Computer and Information SciencesPrincess Nourah bint Abdulrahman UniversityP.O.Box 84428Riyadh11671Saudi Arabia Department of Information Systems and Technology Faculty of Graduate Studies and ResearchCairo UniversityP.O.Box 3753450GizaEgypt

The trend towards smart greenhouses stems from various factors,including a lack of agricultural land area owing to population concentration and housing construction on agricultural land,as well as water *** study proposes building a full farming adaptation model that depends on current sensor readings and available datasets from different agricultural research *** proposed model uses a one-dimensional convolutional neural network(CNN)deep learning model to control the growth of strategic crops,including cucumber,pepper,tomato,and *** proposed model uses the Internet of Things(IoT)to collect data on agricultural operations and then uses this data to control and monitor these operations in real *** helps to ensure that crops are getting the right amount of fertilizer,water,light,and temperature,which can lead to improved yields and a reduced risk of crop *** dataset is based on data collected from expert farmers,the photovoltaic construction process,agricultural engineers,and research *** experimental results showed that the precision,recall,F1-measures,and accuracy of the one-dimensional CNN for the tested dataset were approximately 97.3%,98.2%,97.25%,and 97.56%,*** new smart greenhouse automation system was also evaluated on four crops with a high turnover *** system has been found to be highly effective in terms of crop productivity,temperature management and water conservation.

关键词： Greenhouse wireless sensor network deep learning Internet of Things strategic crops monitoring smart irrigation

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Productivity comparison of radial lateral wells and horizontal snake wells applied to marine gas hydrate reservoir development

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Petroleum 2021年第4期7卷 407-413页

作者： Md Nahin mahmood Boyun Guo Department of Petroleum and Mining Engineering Chittagong University of Engineering&TechnologyChattogram4349Bangladesh Department of Petroleum Engineering University of LouisianaLafayetteLA70504USA

Development of marine gas hydrate resources presents a huge challenge to the energy industry owing to the well production complications such as wellbore collapse,sand production,and low *** lateral wells(RLW)and horizontal snake wells(HSW)have been proposed separately to mitigate these *** compare the productivity potentials of these two types of wells using the recently developed analytical models and field case data from a gas hydrate reservoir in the South China *** is concluded that RLW will yield slightly higher gas productivity than HSW under similar con*** analysis with the well models indicates that the productivity of RLW is directly proportional to the number of laterals,length of laterals,and radius of laterals,while the productivity of HSW is directly proportional to the length and radius of the horizontal *** decision of using RLW or HSW can be made based on economic analysis of well completion and production,which should be addressed in future studies.

关键词： Natural gas hydrate Radial lateral wells Horizontal snake wells Productivity

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Surface Modification of Poly Vinyl Chloride (PVC) Using Low Pressure Argon and Oxygen Plasma

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Plasma Science and Technology 2010年第2期12卷 204-207页

作者： mahmood GHORANNEVISS Sheila SHAHIDI Jakub WIENER Plasma Physics Research Center Science and Research Branch Islamic Azad University Department of Textile Chemistry Faculty of Textile Technical University of Liberec

In this study, commercial poly vinyl chloride （PVC） films were treated by oxygen and argon plasmas in a cylindrical glass tube which was surrounded by a DC variable magnetic field, with different sample positions in the plasma reactor and also different exposure durations. Effects of the plasma treatment on the hydrophilic properties of the films were studied by mea- suring the water drop contact angle on the surface of the samples. The surface topography of the untreated and plasma treated films was analyzed and compared by atomic force microscopy （AFM）. The optical characteristic changes in treated samples were investigated using reflective spectrophotometry. Also, the chemical changes which appeared on the surface of the samples were investigated using Fourier transform infrared spectroscopy （FTIR）. The results show that the plasma treated PVC becomes more hydrophilic with an enhanced wettability. A sharp de- crease in the water contact angle may also be a consequence of the surface texturization. The aging effect on wettability of the samples was also investigated. The results show that the effect of oxygen plasma on the surface properties of the samples is more pronounced compared with that of argon plasma.

关键词： plasma surface modification poly vinyl chloride

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Causes of recurring drought patterns in Xinjiang, China

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Journal of Arid Land 2010年第4期2卷 279-285页

作者： Rashed mahmood Babar KHAN Nansen-Zhu International Research Center Institute of Atmospheric Physics CAS Xinjiang Institute of Ecology and Geography CAS

Xinjiang Uygur Autonomous Region of China, with its unique topography and geographical location receives very less precipitation in summer as compared with other parts of China. The region is a land locked where moisture is supplied only by westerly winds from Atlantic Ocean as the moisture coming from Indian Ocean is mostly blocked by the Himalayas Range and the Tibetan plateau. In such a scenario, Xinjiang faces severe drought conditions offering significant challenges to water management. In this paper, we analyzed the drought periods in Xinjiang and discussed the various factors that might have influenced precipitation over the past forty-four years. For this purpose, we defined three periods of consecutive four years for high and low precipitation intensities. The average observed precipitation was 1.05 mm/day and 0.7 mm/day in summer (June-July-August) for the Tianshan Mountain region and Junggar Basin of Xinjiang, respectively. The drought conditions indicated that high sea level pressure, wind divergence and low convection were the prominent features that caused the droughts, which often do not allow the condensation process to coagulate the tiny water droplets into relatively large raindrops reducing the amount of precipitation in the region. The period of 1983-1986 is the lowest precipitation interval indicating the severe drought in the western Xinjiang (i.e western Tianshan Mountain region), for which, less moisture availability, strong divergence and less convection could be the most influencing factors.

关键词： Xinjiang drought topography moisture availability convection raindrops divergence

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