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A Novel Source Number Estimator Without Complete Eigendecomposition

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A Novel Source Number Estimator Without Complete Eigendecomp...

Desertification hazard zoning in Sistan Region, Iran

2006 8th International Conference on Signal Processing

作者： Qingchun Zhang Zhenghe Feng student member IEEEState Key Laboratory On Microwave And Digital Communication Tsinghua University Senior member IEEE State Key Laboratory On Microwave And Digital Communication Tsinghua University

ISBN: (纸本)0780397371

＜正＞In this paper,we present another novel source number estimator without the complete eigendecomposition,it is based on the Lanczos process and Sturm algorithm and Finally,for the case of a Uniform Circular Array of six isotropic sensors spaced a half wavelength apart with additive and uncorrelated white noise,we provide a simulated data example to evaluate the proposed estimator,which is proved to be very available.

关键词： Parameter estimation

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Journal of Geographical Sciences 2012年第5期22卷 885-894页

作者： Seyed Mahmood HOSSEINI Sahar SADRAFSHARI Mehdi FAYZOL.AHPOUR member of Young Researchers Club Arsanjan Branch Islamic Azad University Arsanjan Irar M.A. student and member of Young Researchers Club Tabriz Branch Islamic Azad University Tabriz Iran Ph.D student and member of Young Researchers Club Tabriz Branch Islamic Azad University Tabriz Iran

Desertification process as a great problem affects most of the countries in the world. This process has a high rate in arid and semiarid areas. Today, human societies are en- countering the desertification phenomenon as a serious problem which causes various ir- reparable damages to economic and social sectors. In order to assess desertification results in production of different regional models for their application in another region the indices should be re-investigated and adjusted to local conditions. Several models have been de- veloped for desertification evaluation. The present study, attempts to assess quantitatively the desertification process has in an area located at Sistan plain of Iran （Niatak region as a case study） by using Modified MEDALUS method. The obtained results indicated that of the whole studied region （comprising 4819.6 acres）, 2651.56 acres （55%） are located in medium de- sertification intensity class, 1269.48 acres （26.34%） are positioned in severe desertification intensity class, and 898.54 acres （18.64%） are placed in vary severe desertification intensity class.

关键词： desertification modified MEDALUS model desertification process Niatak region

Beacon-driven Leader Based Protocol over a GE Channel for MAC Layer Multicast Error Control

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International Journal of Communications, Network and System Sciences 2008年第2期1卷 144-153页

作者： Zhao LI Thorsten HERFET Senior member IEEE Saarland University Germany student member IEEE USTC CS China & Saarland University Germany

In wireless networks current standard MAC layer protocols don’t provide any error correction scheme for broadcast/multicast. In this paper, we enhance a Leader Based Protocol (LBP) and propose a Beacon-driven Leader Based Protocol (BLBP) for the MAC layer multicast error control. To guarantee a very low Packet Loss Ratio (PLR) under strict delay constraints for video multicast over a Gilbert-Elliott (GE) channel, we analyze BLBP and compare it with LBP and different application layer multicast error control schemes via simulation experiments. Both the theoretical analysis and simulation results show that BLBP can correct nearly all the errors for all receivers in the MAC layer and is more efficient than LBP. BLBP is also more efficient than the application layer Automatic Repeat request (ARQ) scheme and the total multicast delay is much shorter. BLBP is very good for real-time multicast applications with strict delay constraints.

关键词： BLBP Multicast Error Control Gilbert-elliott Channel

The Impact of Nature, The Teaching and Learning of Elementary Lessons in students 9-11 Years Old (Case Study: Shiraz Elementary Schools)

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Journal of Architectural Environment & Structural Engineering Research 2021年第1期4卷 1-8页

作者： Neda Mohammadi Sayyid Rasool Keshavarz Zahra Darabi Graduate student in Architecture Member of the Research and Elite Club of Islamic Azad University of BushehrIran member of the Research and Elite Club of Islamic Azad University of Darun Iran Graduate student in Architecture Hafez InstituteShirazIran

In today’s world some changes have been occurred in human lifestyle,these changes,along with the advantages,have led to a series of disadvantages including their disconnection with the *** of the most important areas to re-establish the relationship is the *** presence of nature at schools,and holding some classes in nature,in addition to meeting the special needs of children causes their separation from those small and boring classes as well as their interest in *** study aimed to investigate the role of nature in children’s *** this purpose,third,fourth and fifth grade classes of 3 schools were held outside the school environment and in the nature in 5 *** study is a combinational research and field,indirect observation and library data collection methods were applied,where in the indirect observation,two types of questionnaires were prepared related to the students and teachers and were randomly distributed among 580 students and 50 elementary school *** reliability was assessed using Cronbach’s alpha and it was obtained to be *** results of this study indicate that the physical place as one of the factors in children’s learning has the maximum impact on teaching and learning of *** the end of the study and by investigating the existing factors in the environment we understood that the expansion of the nature and natural light of it causes the students’interest in lessons in nature.

关键词： Expansion of space Nature Physical environment of the class Schools Interest in lessons

Investigation into the Performance of a MIMO System Equipped with ULA or UCA Antennas: BER, Capacity and Channel Estimation

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International Journal of Communications, Network and System Sciences 2009年第6期2卷 491-503页

作者： Xia LIU Marek E. BIALKOWSKI Feng WANG Konstanty BIALKOWSKI student member IEEE School of ITEE The University of Queensland Fellow IEEE School of ITEE The University of Queensland member IEEE National ICT Australia-Queensland Lab

This paper reports on investigations into the performance of a Multiple Input Multiple Output (MIMO) wireless communication system employing a uniform linear array (ULA) at the transmitter and either a uni-form linear array (ULA) or a uniform circular array (UCA) antenna at the receiver. The transmitter is as-sumed to be surrounded by scattering objects while the receiver is postulated to be free from scattering ob-jects. The Laplacian distribution of angle of arrival (AOA) of a signal reaching the receiver is postulated. The performance of bit error rate (BER), capacity and channel estimation for a MIMO system are evaluated for the two cases that the receiver is equipped with ULA or with UCA antennas.

关键词： MIMO BER BPSK FSK Channel Capacity EDOF Channel Estimation ULA UCA Spatial Correlation

Signaling mechanisms for partition-based protection in WDM networks

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Signaling mechanisms for partition-based protection in WDM n...

Measurement of Mercury Distance, by Observing Transit of Mercury

2005'第四届光互联网国际学术会议

作者： Chen-Shie Ho Sy-Yen Kuo Department of CSIE Van-Nung UniversityStudent member IEEE Fellow IEEE

＜正＞Since the survivability becomes more and more important in WDM backbone network design, the signaling strategy corresponding to a protection/restoration scenario upon failures will Influence the performance and then determine the integrity of the total solution. In this paper we will discuss control mechanisms for several representative protection schemes, analyze their adaptation and application, and propose the corresponding to control protocol signaling model and control protocol for a novel dynamic group protection strategy. The simulation results show that the coatrol overhead of our proposed method outperforms the segmented protection and has the benefit on resource utilization and failure restoration speed.

关键词： Protection restoration segmented group WDM

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Journal of Physical Science and Application 2016年第6期6卷 57-62页

作者： Samaneh Shamyati A member of the Astronomy Society of IRAN 15875-3671 Iran A member of Astronomy Center ofRey Shahre Rey Tehran *** Iran student ofphysics Payame noor University (PNU) Tehran 19395-3697 Iran

We will measure the distance between the Sun and the Moon by considering the Parallax and also by considering the Mercury Sun distance. The goal is to utilize the observed data. The way that we have used in this paper is based on two observational data in Iran （Mashhad 36°31′ N, 59°48′ E） and Canada （Yukon Territory 69°27′ N, 33°2′ E）. It is required to mention that in Mercury transition 2016, I had personally collected the first place, Mashhad. In measuring the distance between Mercury and the Sun we have utilized the trigonometry terms and the related formulas. Using all the collected data and studying on the contacts of the mercury, has helped us to reach the best results.

关键词： Distance Sun Earth Mercury IRAN Solar Sun-Mercury parallax.

Effect of maintenance on reliability of Microgrid

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Effect of maintenance on reliability of Microgrid

Age-of-Information-Aware Federated Learning

2010 The 3rd International Conference on Power Electronics and Intelligent Transportation System (PEITS 2010)

作者： Yasser RahmatiKukandeh MehrdadRostami Mohsen Eftekhari Amir SamanMolaviTabrizi Master student - Shahed University Tehran Iran Faculty member - shahed University Tehran Iran

this article examines the impact of maintenance on reliability of *** first analysis of a system with two members has been accommodated and then it has been tested in a microgrid and it has been numerically *** effect... 详细信息

关键词： Mean time tofailure(MTTF) mean time to first failure(MTTFF) Microgrid repair

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Journal of Computer Science & Technology 2024年第3期39卷 637-653页

作者：徐殷肖明军吴晨吴杰周津锐孙贺 student member CCF 1.School of Computer Science and TechnologyUniversity of Science and Technology of ChinaHefei 230026China Suzhou Institute for Advanced Research University of Science and Technology of ChinaSuzhou 215123China School of Data Science University of Science and Technology of ChinaHefei 230026China Department of Computer and Information Sciences Temple UniversityPhiladelphiaPA 19122U.S.A. CCF IEEE

Federated learning(FL)is an emerging privacy-preserving distributed computing paradigm,enabling numerous clients to collaboratively train machine learning models without the necessity of transmitting clients’private datasets to the central *** most existing research where the local datasets of clients are assumed to be unchanged over time throughout the whole FL process,our study addresses such scenarios in this paper where clients’datasets need to be updated periodically,and the server can incentivize clients to employ as fresh as possible datasets for local model *** primary objective is to design a client selection strategy to minimize the loss of the global model for FL loss within a constrained *** this end,we introduce the concept of“Age of Information”(AoI)to quantitatively assess the freshness of local datasets and conduct a theoretical analysis of the convergence bound in our AoI-aware FL *** on the convergence bound,we further formulate our problem as a restless multi-armed bandit(RMAB)***,we relax the RMAB problem and apply the Lagrangian Dual approach to decouple it into multiple ***,we propose a Whittle’s Index Based Client Selection(WICS)algorithm to determine the set of selected *** addition,comprehensive simulations substantiate that the proposed algorithm can effectively reduce training loss and enhance the learning accuracy compared with some state-of-the-art methods.

关键词： federated learning Age of Information restless multi-armed bandit Whittle’s index