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A new integration scheme for application to seismic hybrid simulation

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Earthquake Engineering and Engineering Vibration 2017年第1期16卷 69-81页

作者： Maedeh Zakersalehi Abbas Ali Tasnimi mehdi Ahmadizadeh Faculty of civil and environmental Engineering Tarbiat Modares University School of civil Engineering Sharif University of Technology

Hybrid simulation is a powerful test method for evaluating the seismic performance of structural systems. This method makes it feasible that only critical components of a structure be experimentally tested. This paper presents a newly proposed integration algorithm for seismic hybrid simulation which is aimed to extend its capabilities to a wide range of systems where existing methods encounter some limitations. In the proposed method, which is termed the variable time step （VTS） integration method, an implicit scheme is employed for hybrid simulation by eliminating the iterative phase on experimental element, the phase which is necessary in regular implicit applications. In order to study the effectiveness of the VTS method, a series of numerical investigations are conducted which show the successfulness of the VTS method in obtaining accurate, stable and converged responses. Then, in a comparative approach, the improved accuracy of the VTS method over commonly used integration methods is demonstrated. The stability of the VTS method is also studied and the results show that it provides conditional stability; however, its stability limit is well beyond the accuracy limit. The effect of time delay on the VTS method results is also investigated and it is shown that the VTS method is quite successful in handling this experimental error.

关键词： seismic hybrid simulation numerical integration accuracy stability error index time delay

Traffic Management in Internet of Vehicles Using Improved Ant Colony Optimization

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Computers, Materials & Continua 2023年第6期75卷 5379-5393页

作者： Abida sharif Imran sharif Muhammad Asim Saleem Muhammad Attique Khan Majed Alhaisoni Marriam Nawaz Abdullah Alqahtani Ye Jin Kim Byoungchol Chang Department of Computer Science COMSATS University IslamabadPakistan Faculty of Computing Riphah International UniversityFaisalabadPakistan Department of Computer Science HITEC UniversityTaxilaPakistan Computer Sciences Department College of Computer and Information SciencesPrincess Nourah bint Abdulrahman UniversityRiyadh11671Saudi Arabia Department of Computer Science UET TaxilaTaxilaPakistan Department of Software Engineering UET TaxilaTaxilaPakistan Software Engineering Department College of Computer Engineering and SciencesPrince Sattam bin Abdulaziz UniversityP.O.Box 151Al-Kharj11942KSA Department of Computer Science Hanyang UniversitySeoul04763Korea Center for Computational Social Science Hanyang UniversitySeoul04763Korea

The Internet of Vehicles(IoV)is a networking paradigm related to the intercommunication of vehicles using a *** a dynamic network,one of the key challenges in IoV is traffic management under increasing vehicles to avoid ***,optimal path selection to route traffic between the origin and destination is *** research proposed a realistic strategy to reduce traffic management service response time by enabling real-time content distribution in IoV systems using heterogeneous network ***,this work proposed a novel use of the Ant Colony Optimization(ACO)algorithm and formulated the path planning optimization problem as an Integer Linear Program(ILP).This integrates the future estimation metric to predict the future arrivals of the vehicles,searching the optimal *** the mobile nature of IOV,fuzzy logic is used for congestion level estimation along with the ACO to determine the optimal *** model results indicate that the suggested scheme outperforms the existing state-of-the-art methods by identifying the shortest and most cost-effective ***,this work strongly supports its use in applications having stringent Quality of Service(QoS)requirements for the vehicles.

关键词： Internet of vehicles internet of things fuzzy logic optimization path planning

Combination therapy using evening primrose oil and electrical stimulation to improve nerve function following a crush injury of sciatic nerve in male rats

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Neural Regeneration Research 2017年第3期12卷 458-463页

作者： Omid Badri Parviz Shahabi Jalal Abdolalizadeh Mohammad Reza Alipour Hadi Veladi mehdi Farhoudi Mohsen sharif Zak Tabriz University of Medical Sciences International Branch ArasTabrizIran Neuroscience Research Center Tabriz University of Medical SciencesTabrizIran Immunology Research Center Tabriz University of Medical SciencesTabrizIran Drug Applied Research Center Tabriz University of Medical SciencesTabrizIran Microsystem Fabrication Laboratory Tabriz UniversityTabrizlran Department of Biochemistry Faculty of MedicineTabriz University of Medical SciencesTabrizIran

Peripheral nerve injuries with a poor prognosis are *** primrose oil（EPO） has beneficial biological effects and immunomodulatory *** electrical activity plays a major role in neural regeneration,the present study investigated the effects of electrical stimulation（ES）,combined with evening primrose oil（EPO）,on sciatic nerve function after a crush injury in *** anesthetized rats,the sciatic nerve was crushed using small haemostatic forceps followed by ES and/or EPO treatment for 4 *** recovery of the sciatic nerve was assessed using the sciatic functional *** changes of gastrocnemius muscle atrophy were investigated by light *** changes were assessed by the nerve conduction velocity of sciatic *** was used to determine the remyelination of the sciatic nerve following the *** ＋ ES,EPO,and ES obviously improved sciatic nerve function assessed by the sciatic functional index and nerve conduction velocity of the sciatic nerve at 28 days after *** of the peripheral nerve remyelination marker,protein zero（P0）,was increased in the treatment groups at 28 days after *** atrophy severity was decreased significantly while the nerve conduction velocity was increased significantly in rats with sciatic nerve injury in the injury ＋ EPO ＋ ES group than in the EPO or ES *** speaking,the combined use of EPO and ES may produce an improving effect on the function of sciatic nerves injured by a *** increased expression of P0 may have contributed to improving the functional effects of combination therapy with EPO and ES as well as the electrophysiological and histopathological features of the injured peripheral nerve.

关键词： nerve regeneration peripheral nerve injury sciatic nerve injury evening primrose oil electrical stimulation sciatic functional index cuff electrode neural regeneration

Production of High Purity Multi-Walled Carbon Nanotubes from Catalytic Decomposition of Methane

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Journal of Natural Gas Chemistry 2006年第4期15卷 266-270页

作者： Kong Bee Hong Aidawati Azlin Binti Ismail Mohamed Ezzaham Bin Mohd Mahayuddin Abdul Rahman Mohamed sharif Hussein sharif Zein School of Chemical Engineering Engineering CampusUniversiti Sains Malaysia14300 Nibong TebalSeberang Perai SelatanPulau PinangMalaysia

Acid-based purification process of multi-walled carbon nanotubes （MWNTs） produced via catalytic decomposition of methane with NiO/TiO2 as a catalyst is described. By combining the oxidation in air and the acid refluxes, the impurities, such as amorphous carbon, carbon nanoparticles, and the NiO/TiO2 catalyst, are eliminated. Scanning electron microscopy （SEM） and transmission electron microscopy （TEM） images confirm the removal of the impurities. The percentage of the carbon nanotubes purity was analyzed using thermal gravimetric analysis （TGA）. Using this process, 99.9 wt% purity of MWNTs was obtained.

关键词： multi-walled carbon nanotubes purification acid refluxes oxidation methane decomposition

U-shaped energy loss curves utilization for distributed generation optimization in distribution networks

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Journal of Zhejiang University-Science C(Computers and Electronics) 2013年第11期14卷 887-898页

作者： Reza EBRAHIMI mehdi EHSAN Hassan NOURI Department of Electrical Engineering Science and Research BranchIslamic Azad University Centre of Excellence in Power System Management and Control (CEPSMC) Sharif University of Technology Department of Engineering Design and Mathematics University of the West of England (UWE Bristol)

We propose novel techniques to find the optimal location,size,and power factor of distributed generation(DG) to achieve the maximum loss reduction for distribution *** the optimal DG location and size is achieved simultaneously using the energy loss curves technique for a pre-selected power factor that gives the best DG *** on the network's total load demand,four DG sizes are *** are used to form energy loss curves for each bus and then for determining the optimal DG *** study shows that by defining the energy loss minimization as the objective function,the time-varying load demand significantly affects the sizing of DG resources in distribution networks,whereas consideration of power loss as the objective function leads to inconsistent interpretation of loss reduction and other *** devised technique was tested on two test distribution systems of varying size and complexity and validated by comparison with the exhaustive iterative method(EIM) and recently published *** showed that the proposed technique can provide an optimal solution with less computation.

关键词： Distributed generation(DG) Distribution networks Loss reduction DG optimization Energy loss curves

Impact of seismic excitation characteristics on the efficiency of tuned liquid column dampers

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Earthquake Engineering and Engineering Vibration 2006年第2期5卷 235-243页

作者： Ali Kavand S. mehdi Zahrai School of Civil Engineering Sharif University of Technology Tehran Iran School of Civil Engineering University of Tehran Tehran Iran Associate Professor

Various types of passive control systems have been used to suppress the seismic response of structures in recent years. Among these systems, Tuned Liquid Column Dampers （TLCDs） dissipate the input earthquake energy by combining the effects of the movement of the liquid mass in the container, the restoring force on the liquid due to the gravity loads and the damping due to the liquid movement through orifices. In this study, the effects of seismic excitation characteristics such as frequency content and soil condition on the seismic performance of TLCDs are investigated using nonlinear time-history analyses. In this regard, among the past earthquake ground motion records of Iran, 16 records with different parameters were selected. In the structural model developed, the attached TLCD is simulated as a Tuned Mass Damper （TMD） having the same vibration period and damping ratio as the original TLCD. The numerical results show that the seismic excitation characteristics have a substantial role on the displacement reduction capability of TLCDs and they should be considered accordingly in the design of TLCDs.

关键词： passive control tuned liquid column dampers seismic excitation characteristics frequency content subsoilconditions seismic performance

Mango Leaf Disease Identification Using Fully Resolution Convolutional Network

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Computers, Materials & Continua 2021年第12期69卷 3581-3601页

作者： Rabia Saleem Jamal Hussain Shah Muhammad sharif Ghulam Jillani Ansari COMSATS University Islamabad Wah Campus47040Pakistan University of Education Lahore54000Pakistan

Due to the high demand for mango and being the king of all fruits,it is the need of the hour to curb its diseases to fetch high *** leaf disease segmentation and identification are still a challenge due to variations in *** segmentation of the disease is the key prerequisite for any computer-aided system to recognize the diseases,i.e.,Anthracnose,apicalnecrosis,etc.,of a mango plant *** solve this issue,we proposed a CNN based Fully-convolutional-network(FrCNnet)model for the segmentation of the diseased part of the mango *** proposed FrCNnet directly learns the features of each pixel of the input data after applying some preprocessing *** evaluated the proposed FrCNnet on the real-time dataset provided by the mango research institute,Multan,*** evaluate the proposed model results,we compared the segmentation performance with the available state-of-the-art models,i.e.,Vgg16,Vgg-19,and ***,the proposed model’s segmentation accuracy is 99.2%with a false negative rate(FNR)of 0.8%,which is much higher than the other *** have concluded that by using a FrCNnet,the input image could learn better features that are more prominent and much specific,resulting in an improved and better segmentation performance and diseases’***,an automated approach helps pathologists and mango growers detect and identify those diseases.

关键词： Mango plant leaf disease detection CNN FrCNnet segmentation

Space Efficient Quantization for Deep Convolutional Neural Networks

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Journal of Computer Science & Technology 2019年第2期34卷 305-317页

作者： Dong-Di Zhao Fan Li Kashif sharif Guang-Min Xia Yu Wang School of Computer Science Beijing Institute of Technology Beijing 100081 China Wireless Networking and Sensing Laboratory Department of Computer Science University of North Carolina at Charlotte Charlotte NC 28223 U.S.A.

Deep convolutional neural networks(DCNNs)have shown outstanding performance in the fields of computer vision,natural language processing,and complex system *** the improvement of performance with deeper layers,DCNNs incur higher computational complexity and larger storage requirement,making it extremely difficult to deploy DCNNs on resource-limited embedded systems(such as mobile devices or Internet of Things devices).Network quantization efficiently reduces storage space required by ***,the performance of DCNNs often drops rapidly as the quantization bit *** this article,we propose a space efficient quantization scheme which uses eight or less bits to represent the original 32-bit *** adopt singular value decomposition(SVD)method to decrease the parameter size of fully-connected layers for further ***,we propose a weight clipping method based on dynamic boundary to improve the performance when using lower *** results demonstrate that our approach can achieve up to approximately 14x compression while preserving almost the same accuracy compared with the full-precision *** proposed weight clipping method can also significantly improve the performance of DCNNs when lower precision is required.

关键词： convolutional neural network memory compression network quantization

Modeling of D-STATCOM in distribution systems load flow

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第10期8卷 1532-1542页

作者： HOSSEINI mehdi SHAYANFAR Heidar Ali FOTUHI-FIRUZABAD Mahmud Center of Excellence for Power System Automation and Operation Department of Electrical Engineering Iran University of Science & Technology Narmak 16846-13114 Tehran Iran Technical Engineering of Babol University of Mazandaran Shariati Ave. 47144 P. O. Box 484 Babol Iran Center of Excellence for Power System Automation and Operation Department of Electrical Engineering Iran University of Science & Technology Narmak 16846-13114 Tehran Iran Department of Electrical Engineering Sharif University of Technology Azadi Ave. 11365-9363 Tehran Iran

This paper presents modeling of Distribution STATCOM (D-STATCOM) in load flow calculations for the steady- state voltage compensation. An accurate model for D-STATCOM is derived to use in load flow calculations. The rating of this device as well as the direction of required reactive power injection for voltage compensation in the desired value (1 p.u.) is de- rived and discussed analytically and mathematically by the phasor diagram method. Furthermore, an efficient method for node and line identification used in load flow calculations is presented. The validity of the proposed model is examined by using two standard distribution systems consisting of 33 and 69 nodes, respectively. The best location of D-STATCOM for under voltage problem mitigation approach in the distribution networks is determined. The results validate the proposed model for D- STATCOM in large distribution systems.

关键词： Distribution system D-STATCOM Voltage compensation Load flow