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synthesis of Antennas for Field and polarization Control

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Journal of Electromagnetic Analysis and Applications 2017年第7期9卷 97-112页

作者： Leandro p. s. pereira Marco A. B. Terada Antenna Group Electrical Engineering Department University of Brasilia Brasilia Brazil

This article presents a procedure for electromagnetic field and polarization control with antennas. The concept previously introduced by the authors for spatially distributed three-dimensional electromagnetic polarization (as time varies) is discussed and extended also to include non-ideal antennas and the control of electromagnetic field distributions (at a given instant of time). These polarizations and fields are herein referred to as “3D”, although time is also inherent to them. Even that the main objective is to introduce a mathematically/numerically consistent synthesis technique for controlling the 3D electromagnetic fields and polarizations, an effort is made to present and discuss possible applications, including but not limited to torus-knotted distributions and spatial multiplexing for transmission of information in wireless digital communication systems.

关键词： Antennas Electromagnetic Theory Electric Fields Electromagnetic polarization Three-Dimensional polarization and Orthogonality spatial Multiplexing Transmission of Information Cellular Communication systems Torus-Knots

perceived stress among staff in saudi Arabian dental colleges before and after an accreditation process: A cross-sectional study

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World Journal of Clinical Cases 2024年第4期12卷 758-765页

作者： Amal s shaiban Department of Restorative Dental science College of DentistryKing Khalid UniversityAbha 61471Saudi Arabia

BACKGROUND Accreditation processes are extensively employed to guarantee the quality of higher education ***,this process can potentially generate a stressful atmosphere for staff,thus impacting their ability to perform optimally under *** To examine the knowledge of the National Commission for Academic Assessment and Accreditation(NCAAA)and its effects on perceived stress among dental college staff before and after the program accreditation *** The present cross-sectional questionnaire-based study included 300 employees from three dental *** same employees had to fill out the questionnaire 1 mo after the NCAAA *** Approximately 51.33%of the included employees believed that NCAAA is essential to attract quality students to join the program before and after the program.A total of 44.67%felt that their stress was high before,and 31.33%had low stress levels before and after *** findings were statistically significant(p≤0.05).CONCLUsION NCAAA raised the prestige of the institution and specific programmes and increased prospects to attract better students,staff,and money,according to the *** addition to their needed teaching,research,and other service responsibilities,this work requires a tremendous amount of faculty effort and may cause them stress.

关键词： National Commission for Academic Assessment and Accreditation Accreditation process perceived stress staff

Recent understanding on the subgrid-scale modeling of large-eddy simulation in physical space

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science China(physics,Mechanics & Astronomy) 2014年第12期57卷 2188-2193页

作者： FANG Le sHAO Liang BERTOGLIO J.-p. Laboratory of Mathematics and physics Ecole Centrale de P'ekin Beijing University of Aeronautics and Astronautics Laboratoire de M'ecaniques des Fluides et d'Acoustique Ecole Centrale de Lyon

In the last 50 years,the methodology of large-eddy simulation(LEs)has been greatly developed,while lots of different subgridscale(sGs)models have ***,the understanding of the procedure of sGs modeling is still not *** present contribution aims at reviewing the recent sGs models and,more importantly,expressing our recent understanding on the sGs modeling of LEs in physical *** the Kolmogorov equation for filtered quantities(KEF)as an example,it is argued that the KEF alone is not enough to be a closure *** physical laws are then introduced to complete this closure procedure and are expected to inspire the future researches of sGs modeling.

关键词： large-eddy simulation subgrid-scale modeling Koimogorov equation

Deep Root Memory Optimized Indexing Methodology for Image search Engines

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Computer systems science & Engineering 2022年第2期40卷 661-672页

作者： R.Karthikeyan A.Celine Kavida p.suresh Department CsE Vel Tech HighTech Dr.Rangarajan Dr.Sakunthala Engineering CollegeChennai600062TamilnaduIndia Department of physics Vel Tech Multitech Dr.Rangarajan Dr.Sakunthala Engineering CollegeChennai600062Tamil NaduIndia Department of ECE Veltech Rangarajan Dr Sagunthala R&D Institute of Science and TechnologyChennaiTamilnadu600062India

Digitization has created an abundance of new information sources by altering how pictures are *** large image databases from a web portal requires an opted indexing structure instead of reducing the contents of different kinds of databases for quick *** approach paves a path toward the increase of efficient image retrieval techniques and numerous research in image indexing involving large image *** retrieval usually encounters difficulties like a)merging the diverse representations of images and their Indexing,b)the low-level visual characters and semantic characters associated with an image are indirectly proportional,and c)noisy and less accurate extraction of image information(semantic and predicted attributes).This work clearly focuses and takes the base of reverse engineering and de-normalizing concept by evaluating how data can be stored ***,retrieval becomes straightforward and *** research also deals with deep root indexing with a multidimensional approach about how images can be indexed and provides improved results in terms of good performance in query processing and the reduction of maintenance and storage *** focus on the schema design on a non-clustered index solution,especially cover *** schema provides a filter predication to make an index with a particular content of rows and an index table called filtered ***,we include non-key columns in addition to the key *** on two image data sets‘with and without’filtered indexing show low query *** compare efficiency as regards accuracy in mean average precision to measure the accuracy of retrieval with the developed coherent semantic *** results show that retrieval by using deep root indexing is simple and fast.

关键词： Multi-dimensional indexing deep root hashing image retrieval filtered indexing

DeNOx study in Diesel Engine Exhaust Using Barrier Discharge Corona Assisted by V_2O_5/TiO_2 Catalyst

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plasma science and Technology 2004年第4期6卷 2411-2415页

作者： B.s.Rajanikanth V.Ravi Indian Institute of science Bangalore 560012IndiaIndian Institute of ScienceBangalore 560012India

A plasma-assisted catalytic reactor was used to remove nitrogen oxides (NOx)from diesel engine exhaust operated under different load conditions. Initial studies were focused onplasma reactor (a dielectric barrier discharge reactor) treatment of diesel exhaust at varioustemperatures. The nitric oxide (NO) removal efficiency was lowered when high temperature exhaust wastreated using plasma reactor. Also, NO removal efficiency decreased when 45% load exhaust wastreated. studies were then made with plasma reactor combined with a catalytic reactor consisting ofa selective catalytic reduction (sCR) catalyst, V_2O_5/TiO_2. Ammonia was used as a reducing agentfor sCR process in a ratio of 1:1 to NOx. The studies were focused on temperatures of the sCRcatalytic reactor below 200℃. The plasma-assisted catalytic reactor was operated well to remove NOxunder no-load and load conditions. For an energy input of 96 J/l, the NOx removal efficienciesobtained under no-load and load conditions were 90% and 72% respectively at an exhaust temperatureof 100 ℃.

关键词： non-thermal plasma DeNOx barrier discharge diesel exhaust

Influence of physical and chemical factors during foraging and culture of the symbiont fungus in Atta sexdens rubropilosa （Hymenoptera： Formicidae）

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Insect science 2007年第4期14卷 295-300页

作者： sANDRA s. VERZA LUIZ C. FORTI JULIANE F. s. LOpEs ROBERTO s.CAMARGO CARLOs A. O. MATOs Departamento de Zoologia Instituto de Biociencias Laboratrio de Insetos sociais-praga Departamento de Produ~~o Vegetal-Def-esa Fitossanitaria Faculdade de Ciencias Agronomicas UNESP-Sao Paulo State University Fazenda Experimental LageadoBotucatu SP Comportamento e Biologia Animal Instituto de Ciencias Biologicas UFJF-Universidade Federal de Juiz de ForaCampus Universitario Martelos Juiz de Fora MG Campus Experimental de Itapeva UNESP Itapeva SP Brazil

The aim of this paper is to investigate the influence of physical and chemical factors on transport and use of substrate for Atta sexdens rubropilosa workers. Three types of rectangular fragments were used to study the physical influence factors： filter paper with paraffin, filter paper without paraffin and polyester film. To study the chemical factors, some fragments were impregnated with organic extract of orange albedo, others were soaked with soybean oil and for the remaining ones nothing was applied. The fonowing parameters were evaluated：（i） attractiveness of substrate for transport and number of loading workers per treatment; （ii） foraged material incorporation; （iii） rejection by numbers of fragments deposited in the garbage or beside the fungus garden. All the polyester film fragments carried out to the fungus garden were subsequently rejected. We verified that chemical factors of the substrate were more quickly detected by the workers, whereas physical factors were used as a criterion in the decision-making to reject or accept the substrate collected.

关键词： Atta sexdens rubropilosa attractiveness behavior leaf-cutting ants substraterejection substrate selection

Quantization of particle Energy in the Analysis of the Boltzmann Distribution and Entropy

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Journal of Mathematics and system science 2017年第10期7卷 278-288页

作者： V.p. Malyshev Yu.s. Zubrina A.M. Makasheva Chemical and Metallurgical Institute named after Zh. Abishev Karaganda Kazakhstan

The Boltzmann equilibrium distribution is an important rigorous tool for determining entropy, since this function cannot be measured, but only calculated in accordance with Boltzmann＇s law. On the basis of the commensuration coefficient of discrete and continuous similarly-named distributions developed by the authors, the article analyses the statistical sum in the Boltzmann distribution to the commensuration with the improper integral of the similarly-named function in the full range of the term of series of the statistical sum at the different combination of the temperature and the step of variation （quantum） of the particle energy. The convergence of series based on the Cauchy, Maclaurin criteria and the equal commensuration of series and improper integral of the similarly-named function in each unit interval of variation of series and similarly-named function were estab- lished. The obtained formulas for the commensuration coefficient and statistical sum were analyzed, and a general expres- sion for the total and residual statistical sums, which can be calculated with any given accuracy, is found. Given a direct calculation formula for the Boltzmann distribution, taking into account the values of the improper integral and commensuration coefficient. To determine the entropy from the new expression for the Boltzmann distribution in the form of a series, the conver- gence of the similarly-named improper integral is established. However, the commensuration coefficient of integral and series in each unit interval turns out to be dependent on the number of the term of series and therefore cannot be used to determine the sum of series through the improper integral. In this case, the entropy can be calculated with a given accuracy with a corresponding quantity of the term of series n at a fixed value of the statistical sum. The given accuracy of the statistical sum turns out to be mathematically identical to the fraction of particles with an energy exceeding a given le

关键词： distribution entropy sequence commensuration statistical sum convergent series analysis.

Fast global kernel fuzzy c-means clustering algorithm for consonant/vowel segmentation of speech signal

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Journal of Zhejiang University-science C(Computers and Electronics) 2014年第7期15卷 551-563页

作者： Xian ZANG Felipe p. VIsTA IV Kil To CHONG Department of Electronic Engineering Jeonbuk National University Advanced Electronics and Information Research Center Jeonbuk National University

We propose a novel clustering algorithm using fast global kernel fuzzy c-means-F(FGKFCM-F), where F refers to kernelized feature space. This algorithm proceeds in an incremental way to derive the near-optimal solution by solving all intermediate problems using kernel-based fuzzy c-means-F(KFCM-F) as a local search procedure. Due to the incremental nature and the nonlinear properties inherited from KFCM-F, this algorithm overcomes the two shortcomings of fuzzy c-means(FCM): sen- sitivity to initialization and inability to use nonlinear separable data. An accelerating scheme is developed to reduce the compu-tational complexity without significantly affecting the solution quality. Experiments are carried out to test the proposed algorithm on a nonlinear artificial dataset and a real-world dataset of speech signals for consonant/vowel segmentation. simulation results demonstrate the effectiveness of the proposed algorithm in improving clustering performance on both types of datasets.

关键词： Fuzzy c-means clustering Kernel method Global optimization Consonant/vowel segmentation

Analysis of statistical dependencies between intellectual characteristics and gaming ability,measured with the aid of a computer game

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International Journal of Modeling, simulation, and scientific Computing 2020年第6期11卷 23-44页

作者： A.A.Margolis L.s.Kuravsky s.L.Artemenkov V.K.Voitov E.A.shepeleva E.V.Gavrilova s.s.Ermakov Moscow state University of psychology and Education Moscow Russia

The aim of this paper is testing a computer game as an alternative tool for the assessment of intelligence and creativity of school *** relevance of the research task is determined by the growing interest in practical psychology in the use of computer games as a special diagnostic tool in educational *** are two original factor models that have been developed and the structural equation modeling of measured parameters has been carried *** relationships between game dynamic and final individual results in the computer game,on the one hand,and psychometric intelligence and divergent creativity,on the other,are *** correlation between the above-mentioned and individually measured intellectual and creativity characteristics of the participants with the computer game results was *** of these characteristics in the form of a common latent factor makes it possible to identify the corresponding dependencies only in some cases when there is a dividing the sample into groups according to their ability ***,the dynamics of game scoring allows to refer participants to the target group with a certain level of abilities(high intelligence and creativity versus low intelligence and creativity),and it is the high level of psychological traits that determines effectiveness in the game behavior,but not vice *** qualitative ratios of the two groups of subsets of participants were revealed:weak,medium and strong players and players with three different levels of psychological *** prospects for the further use of computer games for assessment of cognitive abilities in the measurement of combination of psychological abilities are discussed.

关键词： structural equation modeling intellectual characteristics gaming ability psychological diagnostics