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Autonomous fault-diagnosis and decision-making algorithm for determining faulty nodes in distributed wireless networks

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Frontiers of Information Technology & Electronic Engineering 2016年第9期17卷 885-896页

作者： Adel KHOSRAVI Yousef seifi KAVIAN Electrical Engineering Department Faculty of Engineering Shahid Chamran University of Ahvaz

In this paper, we address fault-diagnosis agreement(FDA) problems in distributed wireless networks(DWNs) with arbitrary fallible nodes and healthy access points. We propose a new algorithm to reach an agreement among fault-free members about the faulty ones. The algorithm is designed for fully connected DWN and can also be easily adapted to partially connected networks. Our contribution is to reduce the bit complexity of the Byzantine agreement process by detecting the same list of faulty units in all fault-free members. Therefore, the malicious units can be removed from other consensus processes. Also, each healthy unit detects a local list of malicious units, which results in lower packet transmissions in the network. Our proposed algorithm solves FDA problems in 2t+1 rounds of packet transmissions, and the bit complexity in each wireless node is O(nt+1).

关键词： Fault diagnosis Decision making Byzantine agreement Distributed wireless networks Consensus

Operation and Flexibility Contribution of Natural Gas Tanks in Multi-carrier Energy Systems

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CSEE Journal of Power and Energy Systems 2021年第3期7卷 622-631页

作者： Alireza Hamedi Ali Reza seifi Dariush Keihan Asl School of Electrical and Computer Engineering Shiraz UniversityShirazIran

Energy storage systems(ESSs)have an assistive role in the operation of multi-carrier energy *** paper presents a type of natural gas(NG)ESS called NG tank and studies the operation and flexibility contributions of this ESS in the *** tank modeling and formulation are unified the same as the electrical *** NG tank and the electrical ESS models are implemented on a large-scale multi-carrier energy network and the impressive effects of utilizing these units are investigated in the operational planning of the energy *** optimal operational problem is solved utilizing the teaching learning based optimization(TLBO)algorithm to minimize the operational cost of the system.

关键词： Electrical ESS multi-carrier energy system NG tank optimal operation

Effective Controlled Islanding Method for Power Grids Solving a Sequence of Optimization Problems

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CSEE Journal of Power and Energy Systems 2022年第4期8卷 1004-1012页

作者： Mahdi Amini Haidar Samet Ali Reza seifi Mahdi Davarpanah School of Electrical and Computer Engineering Shiraz UniversityShirazIran Department of Electrical Engineering Eindhoven University of TechnologyEindhoventhe Netherlands the Electrical and Computer Engineering School College of EngineeringUniversity of TehranTehranIran

Controlled islanding is an important approach to prevent instability in power *** this paper,a novel approach is proposed for power system separation,which consists of two steps:1)Finding multiple islanding scenarios;2)Choosing the best option to obtain the most desirable *** the first step,different islanding solutions are determined by a proposed hierarchical clustering *** this algorithm,which is based on a minimum active power flow disruption objective function,the generator coherency constraints are considered in the clustering *** the second step,the best separation scenario is chosen based on an arbitrary objective ***,in this paper,the amount of load shedding and the voltage profile deviation after separation are considered as the final criteria to select the best solution among available *** so doing,the degree of load importance is also taken into *** proposed two-step method is applied on an IEEE 9-bus test system and it is also evaluated on an IEEE 39-bus *** simulation results on the IEEE 39-bus grid and the comparative analysis with a state-of-the-art method confirm that the final islanding solution is more optimized based on the secondary criteria,which have not been addressed in the existing ***,the proposed method is computationally efficient and can be employed in real-scale power grids.

关键词： Graph theory hierarchical spectral clustering power system separation power system instability two-step approach.

A Damage-tolerant Bulk Metallic Glass at Liquid-nitrogen Temperature

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Journal of Materials Science & Technology 2014年第6期30卷 627-630页

作者： Jun Yi S.Mohsen seifi Weihua Wang John J.Lewandowski Department of Materials Science and Engineering Case Western Reserve UniversityClevelandOH 44106-7204 USA Institute of Physics Chinese Academy of Sciences

Tensile tests and notch toughness tests were conducted on Zr61Ti2Cu25Al12 glass （ZT） at room temperature and liquid-nitrogen temperature. The tensile strength of ZT was improved from 1.63 GPa at room temperature to 1.72 GPa at liquid-nitrogen temperature. Micro-notches with a root radius of 1-3μm were introduced to test the notch toughness of ZT at room temperature and liquid-nitrogen temperature. The test results revealed that the notch toughness of ZT at liquid-nitrogen temperature is comparable to that of ZT at room temperature. The combination of high yield strength and notch toughness of ZT at liquid-nitrogen temperature is comparable to that of the best cryogenic engineering materials.

关键词： Metallic glasses Yield strength Fracture toughness Liquid-nitrogen temperature

Two-step probabilistic method to enable demand response programs in renewable-based integrated energy systems

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CSEE Journal of Power and Energy Systems 2019年第99期PP卷 2495-2506页

作者： Jafari, Farshad Samet, Haidar seifi, Ali Reza Rastegar, Mohammad School of Electrical and Computer Engineering Shiraz University Shiraz Electrical Distribution Company Shiraz Iran

This paper presents a two-step procedure to enable residential Demand Response (DR) programs in the Multi-Carrier Energy Systems (MCES), including a combined heat and power generation, renewable resources, a boiler, and energy storage systems. In the first step, an optimization problem is solved to determine the optimal energy cost for each customer. In the second step, the system operator (SO) minimizes the summation of the total loss cost of the electrical distribution system and a designed motivational payment, subject to various operational constraints of the MCES. The motivational payment is the function of deviation of the resulted energy cost of a home in the second step from the desired cost obtained in the first step. The main idea of the proposed procedure is to consider the concerns of customers and the operator, simultaneously. This paper also addresses the uncertainties in renewable resources generation. The proposed procedure is simulated on a test energy system for various cases. The results show that as the level of customer participation in the proposed program is increased, the technical aspects of the integrated energy system are improved. In addition, the customers' costs are decreased by participation in the proposed program. © 2019 CSEE Journal of Power and Energy Systems. All rights reserved.

关键词： Demand Response Energy management Multi-Carrier Energy Systems Two Point Estimation

Bovine salmonellosis in Northeast of Iran:Frequency,genetic fingerprinting and antimicrobial resistance patterns of Salmonella spp.

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Asian Pacific Journal of Tropical Biomedicine 2014年第1期4卷 1-7页

作者： Hessam A.Halimi Hesam A.seifi Mehrnaz Rad Center of Excellence in Ruminant Abortion and Neonatal Mortality and Department of Clinical Sciences School of Veterinary MedicineFerdowsi Unversity of Mashhad Department of Pathobiology School of Veterinary MedicineFerdowsi Unversity of Mashhad

Objective:To evaluate serovar and antimicrobial resistance patterns of Salmonella spp isolated from healthy,diseased and necropsied cows and calves in this observational ***:Nineteen isolates recovered from feces and tissues of salmonellosis-affected animals of two commercial farms in north-east of *** second part of the study,the two farms were sampled 4 times with an interval of 2 *** samples included calves'feces,adult cows'feces,feeds,water,milk filters,and milk fed to *** Salmonella were isolated from 332fecal samples collected from calves and peri-parturient *** Salmonella was recovered from water,feed,milk filers and milk fed to ***:Salmonella Typhimurium was the most frequently isolate among all *** was only accounted for 8%(two out of 24)of *** Salmonella strains were used for the ERIC PCR DNA fingerprinting *** results grouped Salmonella isolates into 3 clusters,suggesting that specific genotypes were responsible for each sero-group of *** results also revealed diversity among Salmonella isolates in cluster III(sero-group B).Eighteen out of 19 Salmonella *** resistant to *** isolates out of 19 showed more than one drug ***-drug resistance was seen only among Salmonella Typhimurium *** was the most susceptible antibiotic against all isolates in this ***:The emergence of multiple antibiotic-resistant strains of Salmonella Typhimurium should be of great concern to the *** correlation between ERIC fingerprinting and resistance patterns of Salmonella isolates was found,which indicates resistance to antimicrobial agents was not related to specific genetic background.

关键词： Dairy cattle Salmonella Typhimurium Antibiotic resistance ERIC PCR

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基于元建模的裂缝性气藏累计产量预测

石油勘探与开发 2013年第2期40卷 215-219页

作者： seifi A Kazemzadeh M B Mohammadi H 伊朗Amirkabir科技大学工业工程系

为了预测某裂缝性气藏在18年规划周期内的累计产量,建立了3种元模型,并结合数值模拟累计产量预测结果对各模型进行了验证和对比。估算了气藏的基本参数(孔隙度、渗透率及含水饱和度)并对气藏进行了数值模拟。将气藏内某井18年内的累计... 详细信息

为了预测某裂缝性气藏在18年规划周期内的累计产量,建立了3种元模型,并结合数值模拟累计产量预测结果对各模型进行了验证和对比。估算了气藏的基本参数(孔隙度、渗透率及含水饱和度)并对气藏进行了数值模拟。将气藏内某井18年内的累计产量表示为各气藏参数的函数,采用储量计算经验函数排除了研究空间内的低潜力点,并基于最大熵准则选取25个高潜力点作为设计点。建立了二次模型、乘性模型和RBF模型3种元模型,基于各模型预测了25个设计点和7个试验点处的累计产量。预测结果表明:各模型均能比较准确地预测累计产量;RBF模型的累计产量预测准确性优于另外2种模型;与数值模拟方法相比,元建模方法的计算时间大幅缩短。

关键词：元建模径向基函数裂缝性气藏产量预测

Optimizing Memory Access Efficiency in CUDA Kernel via Data Layout Technique

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Journal of Computer and Communications 2024年第5期12卷 124-139页

作者： Neda seifi Abdullah Al-Mamun Department of Computer & Cyber Sciences— SCCS Augusta University Augusta Georgia USA

Over the past decade, Graphics Processing Units (GPUs) have revolutionized high-performance computing, playing pivotal roles in advancing fields like IoT, autonomous vehicles, and exascale computing. Despite these advancements, efficiently programming GPUs remains a daunting challenge, often relying on trial-and-error optimization methods. This paper introduces an optimization technique for CUDA programs through a novel Data Layout strategy, aimed at restructuring memory data arrangement to significantly enhance data access locality. Focusing on the dynamic programming algorithm for chained matrix multiplication—a critical operation across various domains including artificial intelligence (AI), high-performance computing (HPC), and the Internet of Things (IoT)—this technique facilitates more localized access. We specifically illustrate the importance of efficient matrix multiplication in these areas, underscoring the technique’s broader applicability and its potential to address some of the most pressing computational challenges in GPU-accelerated applications. Our findings reveal a remarkable reduction in memory consumption and a substantial 50% decrease in execution time for CUDA programs utilizing this technique, thereby setting a new benchmark for optimization in GPU computing.

关键词： Data Layout Optimization CUDA Performance Optimization GPU Memory Optimization Dynamic Programming Matrix Multiplication Memory Access Pattern Optimization in CUDA

Multi-level cross-layer protocol for end-to-end delay provisioning in wireless multimedia sensor networks

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Frontiers of Information Technology & Electronic Engineering 2019年第9期20卷 1266-1276页

作者： Hossein HADADIAN NEJAD YOUSEFI Yousef seifi KAVIAN Alimorad MAHMOUDI Electrical Engineering Department Faculty of EngineeringShahid Chamran University ofAhvazAhvaz ***Iran

Rapid developments in information and communication technology in recent years have posed a significant challenge in wireless multimedia sensor networks(WMSNs).End-to-end delay and reliability are the critical issues in multimedia applications of sensor *** this paper we provide a new cross-layer approach for provisioning the end-to-end delay of the network at a desirable level of the packet delivery ratio(PDR),used here as a measure of network *** the proposed multi-level cross-layer(MLCL)protocol,the number of hops away from the sink is used to set a level for each node.A packet is routed through the path with the minimum hop count to the sink using this level *** proposed protocol uses cross-layer properties between the network and medium access control(MAC)layers to estimate the minimum delay,with which a node can deliver a packet to the *** a node wants to send a packet,the MLCL protocol compares this minimum delay with the time to live(TTL)of a *** the TTL of the packet is higher than the minimum delay,the node sends the packet through the path with the minimum delay;otherwise,the node drops the packet as the node cannot deliver it to the sink within the TTL *** packet dropping improves network performance because the node can send a useful packet instead of an unusable *** results show a superior performance in terms of end-to-end delay and reliability for the proposed protocol compared to state-of-the-art protocols.

关键词： Wireless multimedia sensor networks Cross layering Time to live End-to-end delay Quality of service