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Highly efficient and easy synthesis of 2,4,6-triarylpyridines catalyzed by pentafluorophenylammonium triflate(PFPAT) as a new recyclable solid acid catalyst in solvent-free conditions

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Chinese Chemical Letters 2012年第4期23卷 419-422页

作者： naser Montazeri Saber Mahjoob Department of Chemistry Faculty of SciencesTonekabon BranchIslamic Azad University

Pentafluorophenylammonium triflate（PFPAT） was found to be a highly efficient catalyst for the preparation of 2,4,6- triarylpyridines from the reaction of acetophenone derivatives,aromatic aldehydes and ammonium *** methodology offers several advantages,such as short reaction time,high yields,simple procedure with an easy work-up and the absence of any volatile and hazardous organic *** addition,this catalytic system can act as an active,inexpensive,metal-free,recoverable and recyclable catalyst.

关键词： Pentafluorophenylammonium triflate 2 4 6-Triarylpyridines Solvent-free conditions Organocatalyst Multi-component reaction

V-gorenstein Injective Modules Preenvelopes and Related Dimension

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Acta Mathematica Sinica,English Series 2017年第2期33卷 187-200页

作者： Ahmad KHOJalI naser ZAMANI Faculty of Mathematical Sciences University of Mohaghegh Ardabili Ardabil P. O. Box 56199-11367 Iran

Let R and S be associative rings and sVR a semidualizing （S-R）-bimodule. An R-module N is said to be V-gorenstein injective if there exists a HomR（Zv（R）,-） and HomR（-,Zv（R）） exact exact complex . of V-injective modules Ii and Ii,i ∈ N0, such that N We will call N to be strongly V-gorenstein injective in case that all modules and homomorphisms in the above exact complex are equal, respectively. It is proved that the class of V-gorenstein injective modules are closed under extension, direct summand and is a subset of the Auslander class ,4v（R） which leads to the fact that V-gorenstein injective modules admit exact right Iv （R）-resolution. By using these facts, and thinking of the fact that the class of strongly V-gorenstein injective modules is not closed under direct summand, it is proved that an R-module N is strongly V- gorenstein injective if and only if N @ E is strongly V-gorenstein injective for some V-injective module E. Finally, it is proved that an R-module N of finite V-gorenstein injective injective dimension admits V-Corenstein injective preenvelope which leads to the fact that, for a natural integer n, gorenstein V-injective injective dimension of N is bounded to n if and only if Ext Iv （R）（I, N） = 0 for all modules I with finite Iv （R）-injective dimension.

关键词： V-gorenstein injective module V-injective module semidualizing module Auslander class

Numerical modeling and experimental validation of microstructure in gray cast iron

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International Journal of Minerals,Metallurgy and Materials 2012年第10期19卷 908-914页

作者： Masoud Jabbari Parviz Davami naser Varahram Department of Mechanical Engineering Technical University of DenmarkKgs.Lyngby 2800Denmark Department of Materials Science and Engineering Sharif University of TechnologyTehran 11365Iran

To predict the amount of different phases in gray cast iron by a finite difference model （FDM） on the basis of cooling rate （R）, the volume fractions of total y phase, graphite, and cementite were calculated. The results of phase composition were evaluated to find a proper correlation with cooling rate. More trials were carried out to find a good correlation between the hardness and phase composition. New proposed formulas show that the hardness of gray cast iron decreases as the amount of graphite phase increases, and increases as the amount of cementite inereases. The,qe fnrrnulas are develoned to correlate the nhase volume fraction to hardness. The results are compared with exverimental data and show reasonable agreement.

关键词： cast iron cooling microstructure mechanical properties finite difference method

Indoor navigation: state of the art and future trends

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Satellite Navigation 2021年第1期2卷 88-110页

作者： naser El-Sheimy You Li Department of geomatics Engineering University of Calgary2500 University Drive N.WCalgaryAB T2N 1N4Canada

This paper reviews the state of the art and future trends of indoor Positioning,Localization,and Navigation(PLAN).It covers the requirements,the main players,sensors,and techniques for indoor *** than the navigation sensors such as Inertial Navigation System(INS)and global Navigation Satellite System(gNSS),the environmental-perception sensors such as High-Definition map(HD map),Light Detection and Ranging(LiDAR),camera,the fifth generation of mobile network communication technology(5g),and Internet-of-Things(IoT)sig.als are becoming important aiding sensors for *** PLAN systems are expected to be more intelligent and robust under the emergence of more advanced sensors,multi-platform/multi-device/multi-sensor information fusion,self-learning systems,and the integration with artificial intelligence,5g,IoT,and edge/fog computing.

关键词： Navigation Indoor positioning Information fusion Wireless localization Dead reckoning Database matching

One-pot synthesis of 1,3-thiazolidin-4-one using Bi(SCH_2COOH)_3 as catalyst

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Chinese Chemical Letters 2013年第5期24卷 389-391页

作者： naser Foroughifar Sattar Ebrahimi Faculty of Chemistry North Tehran BranchIslamic Azad University Department of Chemistry Malayer Branch Islamic Azad University

A catalytic multi-component reaction involving aromatic amine,aromatic aldehydes,mercapto acid as substrates and Bi（SCH_2COOH）_3 as catalyst under solvent free conditions,afforded thiazolidin-4-one in good *** efficiency of the catalyst was proved with a variety of substrates,ranging from electrondeficient to electron-rich aldehydes.

关键词： Thiazolidin-4-one Mercapto acid Multicomponent Thioglycolic acid

Low Cost,Low Power Magnetic IEDs Detection Method Using Biaxial Magnetometry Digital Sensors

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Journal of Electronic Science and Technology 2016年第3期14卷 229-233页

作者： Hamzah naser alrawi Widad Ismail the auto-id Laboratory School of Electrical&Electronics EngineeringEngineering CampusUniversiti Sains MalaysiaNibong TebalPenangMalaysia

The magnetic improvised explosive devices （IEDs）, also commonly known as a type of a sticky bomb, is simply constructed devices yet very lethal. This paper puts forward the idea of an electronic compass that is capable of sensing the change of a magnetic field generated by a magnet and translating it into interpretable data, which could act as the base for the further studies and assist in developing a greener automated system for detecting this device. The electronic compass is specifically chosen for reducing power consumption of systems in addition to the fact that it is available at a low cost.

关键词： Compass detect low power sensor improvised explosive devices (lED) magnets magnetometer.

Inertial sensors technologies for navigation applications:state of the art and future trends

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Satellite Navigation 2020年第1期1卷 9-29页

作者： naser El-Sheimy Ahmed Youssef Mobile Multi-sensor Systems Research Team Department of Geomatics EngineeringUniversity of Calgary2500 University Drive N.WCalgaryAB T2N 1N4Canada

Inertial navigation represents a unique method of navigation,in which there is no dependency on external sources of *** opposed to other position fixing navigation techniques,inertial navigation performs the navigation in a relative sense with respect to the initial navigation state of the moving ***,inertial navigation systems are not prone to jamming,or *** navigation systems have developed vastly,from their occurrence in the 1940s up to *** accuracy of the inertial sensors has improved over time,making inertial sensors sufficient in terms of size,weight,cost,and accuracy for navigation and guidance *** the past few years,inertial sensors have developed from being purely mechanical into incorporating various technologies and taking advantage of numerous physical phenomena,from which the dynamic forces exerted on a moving body could be computed ***,the evolution of inertial navigation scheme involved the evolution from stable-platform inertial navigation system,which were mechanically complicated,to computationally demanding strap-down inertial navigation *** sensory technologies have provided highly accurate inertial sensors,at smaller ***,the vibratory inertial navigation technologies enabled the production of Micro-electro-machined inertial sensors that are extremely low-cost,and offer extremely low size,weight and power consumption,making them suitable for a wide range of day-to-day navigation ***,advanced inertial sensor technologies have been introduced to the industry such as nuclear magnetic resonance technology,coldatom technology,and the reintroduction of fluid-based inertial *** another note,inertial sensor errors constitute a huge research aspect in which it is intended for inertial sensors to reach level in which they could operate for substantially long operation times in the absence of updates from aiding sensors,which would be a hug

关键词： gyroscopes Accelerometers Optical inertial sensors Micro-electro-machined Fluid-based inertial sensors Stochastic modeling

Evaluation of Different Predictor Models for Detailed Soil Particle-Size Distribution

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Pedosphere 2018年第1期28卷 157-164页

作者： Fatemeh MESKINI-VISHKAEE naser DAVATgAR Soil and Water Research Department Khuzestan Agricultural and Natural Resources Research and Education Center Agricultural Research Education and Extension Organization (AREEO) Soil and Water Research Institute Agricultural Research Education and Extension Organization (AREEO)

An accurate mathematical representation of soil particle-size distribution(PSD) is required to estimate soil hydraulic properties or to compare texture measurements using different classification systems. However, many databases do not contain full PSD data,but instead contain only the clay, silt, and sand mass fractions. The objective of this study was to evaluate the abilities of four PSD models(the Skaggs model, the Fooladmand model, the modified gray model gM(1,1), and the Fredlund model) to predict detailed PSD using limited soil textural data and to determine the effects of soil texture on the performance of the individual PSD *** mean absolute error(MAE) and root mean square error(RMSE) were used to measure the goodness-of-fit of the models, and the Akaike's information criterion(AIC) was used to compare the quality of model fits. The performance of all PSD models except the gM(1,1) improved with increasing clay content in soils. This result showed that the gM(1,1) was less dependent on soil *** Fredlund model was the best for describing the PSDs of all soil textures except in the sand textural class. However, the gM(1,1) showed better performance as the sand content increased. These results indicated that the Fredlund model showed the best performance and the least values of all evaluation criteria, and can be used using limited soil textural data for detailed PSD.

关键词： Akaike's information criterion Fredlund model gray model mean absolute error root mean square error soil texture

Proactive Load Balancing Mechanism for Fog Computing Supported by Parked Vehicles in IoV-SDN

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China Communications 2021年第2期18卷 271-289页

作者： Ahmed Jawad Kadhim Jaber Ibrahim naser Ministry of Education General Directorate for Education in Al-QadisiyahAl-Qadisiyah 58002Iraq

Internet of Vehicles(IoV)is a new style of vehicular ad hoc network that is used to connect the sensors of each vehicle with each other and with other vehicles’sensors through the *** sensors generate different tasks that should be analyzed and processed in some given period of *** send the tasks to the cloud servers but these sending operations increase bandwidth consumption and *** computing is a simple cloud at the network edge that is used to process the jobs in a short period of time instead of sending them to cloud computing *** some situations,fog computing cannot execute some tasks due to lack of ***,in these situations it transfers them to cloud computing that leads to an increase in latency and bandwidth occupation ***,several fog servers may be fuelled while other servers are *** implies an unfair distribution of *** this research study,we shall merge the software defined network(SDN)with IoV and fog computing and use the parked vehicle as assistant fog computing *** can improve the capabilities of the fog computing layer and help in decreasing the number of migrated tasks to the cloud *** increases the ratio of time sensitive tasks that meet the *** addition,a new load balancing strategy is *** works proactively to balance the load locally and globally by the local fog managers and SDN controller,*** simulation experiments show that the proposed system is more efficient than VANET-Fog-Cloud and IoV-Fog-Cloud frameworks in terms of average response time and percentage of bandwidth consumption,meeting the deadline,and resource utilization.

关键词： IoV parked vehicles SDN fog computing load balancing