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一种新的主从异步复制协议(英文)

一种新的主从异步复制协议(英文)

Reliable Network Design Problem under Node Failure with Benders Decomposition

第十九届全国数据库学术会议

作者：杨朝红宫云战刘海燕桑伟前李庆艳 Department of Information engineering Armored Force engineering inst.tute

Data is replicated at multiple network nodes for performance and *** copy lazy update protocols have become popular for their superior performance *** this paper,we propose a new primary lazy replica update protocol that guarantees serializability when the copy graph is a directed acyclic *** our protocol,the execution order of a secondary transaction is serialized by the PTES(Primary Transaction Executeing Sequence),which is the unique global transaction execution sequence in the *** also extend our protocol for arbitrary copy *** the copy graph contains cycles,system’s response time may increase for primary transaction may have to wait for a serializable *** remains a problem for current replication *** avoiding significant messaging overhead in the network,our protocol can achieve higher scalability.

关键词： Data replication Serializability Primary lazy replica update protocol

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Applied Mathematics 2014年第2期5卷 241-255页

作者： Tie Liu Wenguo Yang Jun Huang College of engineering University of Chinese Academy of Sciences Beijing China School of Mathematics Sciences University of Chinese Academy of Sciences Beijing China

The design of telecommunication network with capacity constraints of links, routers and ports of routers is considered in this paper. Specially, we limit each demand flow traversed through a pre-specified maximal number of links (called hops) under node failure scenarios in IP layer network. Such a design must be the most cost-effective and ensure that feasible flows continue to exist even when any relay node of the network fails. We propose a reliable mixed-integer programming (MIP) model with multi-scenario constraints to optimally design a minimum-cost survivable IP network that continues to support a good communication under any node failure scenario. Then we transform the MIP model into many single scenario models, that is, simplified MIPs, nonlinear programming (NLP) models and MIP models under Benders decomposition Then we transform the MIP model into many single scenario models, that is, simplified MIPs, nonlinear programming (NLP) models and MIP models under Benders decomposition. Three heuristic methods are proposed to solve these models including branch-and-bound algorithm, global algorithm for NLP, and heuristic algorithm based on benders decomposition. We mainly study the application of Benders decomposition method, where dual model and bounding procedures are given for each MIP model under Benders decomposition at each scenario. The results of our computational experiments validate the effectiveness of the proposed models and algorithms.

关键词： Mixed-Integer Programming Benders Decomposition Network Design Node Failure

POWER AND SPECTRALLY EFFICIENT DJ-FQPSK FOR PCS AND CELLULAR MOBILE COMMUNICATIONS

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POWER AND SPECTRALLY EFFICIENT DJ-FQPSK FOR PCS AND CELLULAR...

Hundredfold increase of stimulated Brillouin-scattering bandwidth in whispering-gallery mode resonators

International Conference on Communication Technology(ICCT’94)

作者： Yanpeng Guo Kamilo Feher Digital Communications Research Lab.Dept.of Electrical engineering University of California Davis DavisCA 95616 Dept.of Electrical engineering University of California Davis and Consulting GroupDIGCOM Inc.DavisCA 95616

＜正＞A newly developed constant envelope FQPSK modem/radio architecture,which employs a modified double-jump（DJ） filter in the crosscorrelated FQPSK system[1-3],is proposed for personal communications systems（PCS） and mobile radio *** efficiency, spectrum efficiency,BER,and system capacity of this system are Investigated in a non-linear amplified（NLA） Rayleigh fading environment. We demonstrate that with the simplest threshold detectors（binary robust eye diagrams inⅠand Q channels）,this system is 4-7 dB more power efficient than the US digital cellular and Japanese Handyphone standardπ/4-QPSK,50%-100% more spectrally efficient than the European standard GMSK,and it almost double the capacity of GMSK.

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Photonics Research 2023年第6期11卷 917-924页

作者： GUOPING LIN JINGYI TIAN TANG SUN QINGHAI SONG YANNE K.CHEMBO Ministry of Industry and Information Technology Key Laboratory of Micro-Nano Optoelectronic Information System School of ScienceHarbin Institute of TechnologyShenzhen 518055China Guangdong Provincial Key Laboratory of Semiconductor Optoelectronic Materials and Intelligent Photonic Systems Shenzhen 518055China Department of Electrical and Computer engineering&inst.tute for Research in Electronics and Applied Physics(IREAP) University of MarylandCollege ParkMaryland 20742USA

Backward stimulated Brillouin scattering(SBS)is widely exploited for various applications in optics and *** typically features a narrow gain bandwidth of a few tens of megahertz in fluoride *** we report a hundredfold increase of SBS bandwidth in whispering-gallery mode *** crystalline orientation results in a large variation of the acoustic phase velocity upon propagation along the periphery,from which a broad Brillouin gain is *** 2.5 GHz wide Brillouin gain profile is theoretically found and experimentally *** phenomena with Brillouin shift frequencies ranging from 11.73 to 14.47 GHz in ultrahigh Q Z-cut magnesium fluoride cavities pumped at the telecommunication wavelength are ***,the Brillouin-Kerr comb in this device is *** 400 comb lines spanning across a spectral window of 120 nm are *** finding paves a new way for tailoring and harnessing the Brillouin gain in crystals.

关键词： scattering pumped Brillouin

Lightweight porous silica foams with extreme-low dielectric permittivity and loss for future 6G wireless communication technologies

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Nano Research 2021年第5期14卷 1450-1456页

作者： Petra S.Pálvölgyi Daniel Sebők Imre Szenti Eva Bozo Henri Ervasti Olli Pitkänen Jari Hannu Heli Jantunen Marko E.Leinonen Sami Myllymäki Akos Kukovecz Krisztian Kordas Microelectronics Research Unit Faculty of Information and Electrical EngineeringUniversity of OuluP.O.Box 4500FI-90570OuluFinland Interdisciplinary Excellence Centre Department of Applied and Environmental ChemistryUniversity of SzegedRerrich Béla tér 1H-6720SzegedHungary Centre for Wireless Communications University of OuluP.O.Box 4500FI-90570OuluFinland

In the next generation wireless communication systems operating at near terahertz frequencies, dielectric substrates with the lowest possible permittivity and loss factor are becoming essential. In this work, highly porous (98.9% ± 0.1%) and lightweight silica foams (0.025 ± 0.005 g/cm3), that have extremely low relative permittivity (εr = 1.018 ± 0.003 at 300 GHz) and corresponding loss factor (tan δtelecommunication devices. Here, micropatterns of Ag thin films are sputtered on the substrates through a shadow mask to demonstrate double split-ring resonator metamaterial structures as radio frequency filters operating in the sub-THz band.

关键词： low-permittivity materials low-loss dielectrics templated sol-gel synthesis silica foams 6G telecommunication

Suitability of Suluu-Terek Basalt Deposits for Stone Casting

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Journal of Minerals and Materials Characterization and engineering 2022年第1期10卷 1-14页

作者： Zhanbolot Aidaraliev Imiyla Rysbaeva Rakhat Atyrova Akimbek Abdykalykov Baktygul Bekbolot Kyzy Chynara Zholdoshova Nematilla Sopubekov Altynbek Kuduev Iurii Dubinin Zhypargul Abdullaeva Department of Physics and Applied Chemistry Kyrgyz State University of Building Transport and Architecture Named after N. Isanov Bishkek Kyrgyzstan Department of Light Industry Product Technology Kyrgyz State Technical University Named after I. Razzakov Bishkek Kyrgyzstan Department of Automated Systems and Digital Technologies Osh State University Osh Kyrgyzstan Department of inst.tute of Chemistry and Biotechnology Kyrgyz Republic National Academy of Sciences Bishkek Kyrgyzstan Department of Networks and telecommunication Systems Osh Technological University Osh Kyrgyzstan Science and Research Department Osh State University Osh Kyrgyzstan

This article is presenting history of stone casting and analysis of basalt raw materials assessment from other countries for stone casting technology and various basalts compositions were considered. Analytical methods for calculating composition of charge require a long calculation time and plotting diagrams, each method has its own advantages and disadvantages. As a research significance, we have proposed an experimental calculation method for calculating raw materials after charging. Analysis of the composition, structure of basalts and charging materials were used in the stone casting technology. According to the comparison method, the required amount of charging materials was calculated for the Suluu-Terek 1, Suluu-Terek 2 and Berestovetsk deposits. The calculated data was confirmed by experimental melts in the process of stone casting.

关键词： Petrology Basalt-Stone Casting Suitability of Raw Materials Aluminosilicate Crystalline Alloy Charging Raw Material Comparison Method

Dual-band reflective polarization converter based on metasurface

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Optoelectronics Letters 2023年第12期19卷 716-720页

作者： LIN Xiaofang ZHANG Xu CHANG Ming LI Wenqiang YU Siyang ZHANG Maolong Air Force Communications NCO Academy Dalian I16000China Shandong Provincial Key Laboratory of Laser Polarization and Information Technology School of Physics and Physical EngineeringQufu Normal UniversityQufu 273165China Shanghai Key Laboratory of Special Artificial Microstructure Materials and Technology Shanghai 200092China

In this paper,a dual-band and reflective polarization converter based on metasurface is *** unit cell is composed of two layers of metal plates separated by a dielectric *** simulation results show that the proposed converter is able to convert x-or y-polarized incident waves into cross-polarized waves perfectly in frequency bands of 6.75–10.59 GHz and 17.78–19.61 GHz,and the polarization conversion ratio(PCR)is nearly 100%,which can also convert linearly polarized waves into circularly polarized waves at four *** can be widely used in applications of radar satellites,antenna design and telecommunication with the function of realizing polarization conversion in two bands and achieving high PCR simultaneously.

关键词： polarization reflective converter

Tele-Healthcare Monitoring System-Based for the Management of Diabetes Emergencie

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E-Health telecommunication Systems and Networks 2021年第4期10卷 83-94页

作者： Julius Olasunmibo Ogunniyi Justice Ono Emuoyibofarhe Michael Adeyemi Olamoyegun Department of Computer engineering Faculty of Engineering Elizade University Ilara-Mokin Nigeria Department of Information System Faculty of Computing and Informatics Ladoke Akintola University of Technology Ogbomoso Nigeria Department of Medicine Endocrinology Diabetes & Metabolism Unit Faculty of Clinical Sciences Ladoke Akintola University of Technology/LAUTECH Teaching Hospital Ogbomoso Nigeria

Introduction: Diabetes mellitus is a global health burden whose prevalence is increasing worldwide. Remote patient monitoring, an automated process which involve transmission of data swiftly from the person with diabetes to the health care providers is often considered to be a technological solution to the challenges of health care delivery with potential of reducing both morbidity and mortality. While the use of telehealth in diabetes management is becoming more prominent, however its use in the management of diabetes emergencies is not very common. Objective: To evaluate telehealth intervention in the management of patient with diabetes in the emergency setting with resultant early diagnosis and management. Methods: This paper presents a design, implementation and evaluation of Tele-healthcare monitoring system with the aids of GPS, smartphone and cellular network infrastructure to monitor patients with diabetes especially during diabetic emergencies. This system depends on remote monitoring of patient when away from the place of domicile or their treating doctor or family members using patient’s data. Patient can also be linked to nearby hospitals using GPS and the attending doctors would have access to patient’s data. Alarm is also issued by the system to the next-of-kin/family members or care giver by sending emergency SMS including the location, time and patient’s clinical condition. The developed system consists of mobile application and web based application. The Mobile application was developed with JAVA programming language and SQLite database. Results: The result from the evaluation of the developed system shows effectiveness of 83.33% and mean users’ perception of 94%. Conclusion: This system is simple and cost-effective to be implemented and enables early intervention when the blood glucose is abnormally high or low in order to save life of the patient without delay.

关键词： Diabetes Telehealth Remote Monitoring Smartphone GPS

一种基于IP的移动式电力应急通讯系统的设计和实现

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数字社区&智能家居 2008年第11期 72-75页

作者：胡瑞崔巍唐毅谢张宾王华彬 Hefei Electronic engineering inst.tute

移动式电力应急通讯系统具有良好的移动性以及强大的互连互通能力,在自然灾害、紧急事故、突发安全事件中起着重要的应急通讯作用。本文结合具体的工程实施方案,研究了基于IP的移动式电力应急通讯系统的构成、原理、涉及到的关键技术以... 详细信息

移动式电力应急通讯系统具有良好的移动性以及强大的互连互通能力,在自然灾害、紧急事故、突发安全事件中起着重要的应急通讯作用。本文结合具体的工程实施方案,研究了基于IP的移动式电力应急通讯系统的构成、原理、涉及到的关键技术以及系统的实现。

关键词：电力应急 voip sip