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On Density-Based Data Streams Clustering Algorithms: A Survey

Journal of Computer Science & Technology 2014年第1期29卷 116-141页

作者： Amineh Amini Teh Ying Wah hadi Saboohi IEEE Department of Information Systems Faculty of Computer Science and Information Technology University of Malaya Kuala Lumpur ACM

Clustering data streams has drawn lots of attention in the last few years due to their ever-growing presence. Data streams put additional challenges on clustering such as limited time and memory and one pass clustering. Furthermore, discovering clusters with arbitrary shapes is very important in data stream applications. Data streams are infinite and evolving over time, and we do not have any knowledge about the number of clusters. In a data stream environment due to various factors, some noise appears occasionally. Density-based method is a remarkable class in clustering data streams, which has the ability to discover arbitrary shape clusters and to detect noise. Furthermore, it does not need the nmnber of clusters in advance. Due to data stream characteristics, the traditional density-based clustering is not applicable. Recently, a lot of density-based clustering algorithms are extended for data streams. The main idea in these algorithms is using density- based methods in the clustering process and at the same time overcoming the constraints, which are put out by data streanFs nature. The purpose of this paper is to shed light on some algorithms in the literature on density-based clustering over data streams. We not only summarize the main density-based clustering algorithms on data streams, discuss their uniqueness and limitations, but also explain how they address the challenges in clustering data streams. Moreover, we investigate the evaluation metrics used in validating cluster quality and measuring algorithms＇ performance. It is hoped that this survey will serve as a steppingstone for researchers studying data streams clustering, particularly density-based algorithms.

关键词： data stream density-based clustering grid-based clustering micro-clustering

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Fracture analyses of different pre-holed concrete specimens under compression

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Acta Mechanica Sinica 2015年第6期31卷 855-870页

作者： hadi Haeri Alireza Khaloo Mohammad Fatehi Marji Department of Civil Engineering Sharif University of Technology Member of National Elites Foundation Center of Excellence in Structure and Earthquake Engineering Sharif University of Technology Mine Exploitation Engineering Department Faculty of Mining and Metallurgy Yazd University

Crack propagation processes in specially prepared concrete discs and rectangular specimens containing a single cylindrical hole or multiple holes of varying diameters have been studied both experimentally and numerically. In this research, the cracks coalescence paths in Brazilian disc and rectangular specimens made from rock-like material containing multi-holes are investigated. These concrete specimens are specially prepared from an appropriate mixture of Portland Pozzolana Cement （PPC）, fine sands, and water. The pre-holed Brazilian discs and rectangular specimens are experimentally tested under compression. The breakage load in the ring type disc specimens containing an axial hole with varying diameters is measured and the distribution of the induced lateral stress is obtained. The mechanism of cracks propagation in the wall of the ring type specimens is also stud- ied. In the case of multi-hole Brazilian disc and rectangular specimens, the cracks propagation and cracks coalescence are also investigated. These experiments are numerically modeled by a modified higher order displacement discontinuity method. It has been shown that the corresponding experimental and numerical results are in good agreement with each other. The results presented in this research vali date the accuracy and applicability of these crack analyses procedures.

关键词： Concrete rings Pre-holed Brazilian disc ·Rectangular specimens Crack analyses Coalescence ·Induced lateral stress

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Improvement in IBC-silicon solar cell performance by insertion of highly doped crystalline layer at heterojunction interfaces

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Chinese Physics B 2017年第10期26卷 508-514页

作者： hadi Bashiri Mohammad Azim Karami Shahramm Mohammadnejad School of Electrical Engineering Iran University of Science &Technology (IUST)

By inserting a thin highly doped crystalline silicon layer between the base region and amorphous silicon layer in an interdigitated back-contact （IBC） silicon solar cell, a new passivation layer is investigated. The passivation layer performance is characterized by numerical simulations. Moreover, the dependence of the output parameters of the solar cell on the additional layer parameters （doping concentration and thickness） is studied. By optimizing the additional passivation layer in terms of doping concentration and thickness, the power conversion efficiency could be improved by a factor of 2.5%, open circuit voltage is increased by 30 mV and the fill factor of the solar cell by 7.4%. The performance enhancement is achieved due to the decrease of recombination rate, a decrease in solar cell resistivity and improvement of field effect passivation at heterojunction interface. The above-mentioned results are compared with reported results of the same conventional interdigitated back-contact silicon solar cell structure. Furthermore, the effect of a-Si：H/c-Si interface defect density on IBC silicon solar cell parameters with a new passivation layer is studied. The additional passivation layer also reduces the sensitivity of output parameter of solar cell to interface defect density.

关键词： IBC silicon solar cells interface layer recombination interface defect density

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Vehicle path tracking by integrated chassis control

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Journal of Central South University 2015年第4期22卷 1378-1388页

作者： Saman Salehpour Yaghoub Pourasad Seyyed hadi Taheri Department of Mechanical Engineering Tabriz Branch Islamic Azad University Faculty of Electrical Engineering Urmia university of Technology Young Researchers and Elite Club Tabriz Branch Islamic Azad University

The control problem of trajectory based path following for passenger vehicles is studied. Comprehensive nonlinear vehicle model is utilized for simulation vehicle response during various maneuvers in MATLAB/Simulink. In order to follow desired path, a driver model is developed to enhance closed loop driver/vehicle model. Then, linear quadratic regulator(LQR) controller is developed which regulates direct yaw moment and corrective steering angle on wheels. Particle swam optimization(PSO) method is utilized to optimize the LQR controller for various dynamic conditions. Simulation results indicate that, over various maneuvers, side slip angle and lateral acceleration can be reduced by 10% and 15%, respectively, which sustain the vehicle stable. Also, anti-lock brake system is designed for longitudinal dynamics of vehicle to achieve desired slip during braking and accelerating. Proposed comprehensive controller demonstrates that vehicle steerability can increase by about 15% during severe braking by preventing wheel from locking and reducing stopping distance.

关键词：车辆模型路径跟踪底盘控制 Simulink 综合控制器防抱死制动系统粒子群优化集成

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Using an Inhibitor to Prevent Plasticizer Migration from Polyurethane Matrix to EPDM Based Substrate

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Chinese Journal of Polymer Science 2019年第7期37卷 681-686页

作者： hadi Rezaei-Vahidian Tohid Farajpour Mahdi Abdollahi Space Transportation Research Institute Iranian Space Research CenterTehranIran Polymer Reaction Engineering Department Faculty of Chemical EngineeringTarbiat Modares UniversityTehranIran

The loss of adhesion between the propellant and insulator is one of the most important problems in solid propellant motors due to migration of plasticizer to interface of propellant and insulator. In this work, the polyurethane (PU) binder containing DOP plasticizer was used as a polymeric matrix and β-cyclodextrin (β-CD) was applied as inhibitor agent to prevent plasticizer migration from the PU matrix into the ethylene propylene diene monomer (EPDM) substrate. To increase the compatibility of β-CD and PU matrix, a derivative of β-CD has been synthesized using toluene diisocyanate (β-CD-TDI). The synthesized derivative was characterized by MALDI-MS and FTIR-ATR analyses. FTIR-ATR results confirmed the formation of bonding between β-CD and the polymeric network while the MALDIMS results showed that the synthesized derivative contained two β-CD and 7 TDI molecules bonded to β-CD. Investigation of the mechanical properties of PU modified by β-CD-TDI showed a decrease in tensile strength and an increase in elongation at break with increasing β-CD-TDI content. DMTA results showed a decrement in crosslinking density by increasing the β-CD-TDI content. Also, to investigate plasticizer migration, extraction of the DOP plasticizer from samples was performed using dichloromethane solvent and its concentration was measured by gas chromatography. The results of migration evaluation after four months showed that using β-CD as an inhibitor agent in the PU binder could prevent the migration of plasticizer to EPDM substrate.

关键词： Plasticizer migration β-Cyclodextrin Polyurethane

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Structural and biological engineering of 3D hydrogels for wound healing

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生物活性材料(英文) 2023年第6期24卷 197-235页

作者： Mohammad hadi Norahan Sara Cristina Pedroza-González Mónica Gabriela Sánchez-Salazar Mario Moisés Álvarez Grissel Trujillo de Santiago Escuela de Ingeniería y Ciencias Tecnológico de MonterreyMonterreyNL64849Mexico Centro de Biotecnología-FEMSA Tecnológico de MonterreyMonterreyNuevo LeónCP64849Mexico Departamento de Bioingeniería Tecnológico de MonterreyMonterreyNuevo LeónCP64849Mexico

Chronic wounds have become one of the most important issues for healthcare systems and are a leading cause of death *** dressings are necessary to facilitate wound *** wound dressings may substantially reduce healing time,reduce the risk of recurrent infections,and reduce the disability and costs *** the path of engineering of an ideal wound dressing,hydrogels have played a leading *** are 3D hydrophilic polymeric structures that can provide a protective barrier,mimic the native extracellular matrix(ECM),and provide a humid *** to their advantages,hydrogels(with different architectural,physical,mechanical,and biological properties)have been extensively explored as wound dressing *** we describe recent studies on hydrogels for wound healing applications with a strong focus on the interplay between the fabrication method used and the architectural,mechanical,and biological performance ***,we review different categories of additives which can enhance wound regeneration using 3D hydrogel *** engineering for wound healing applications promises the generation of smart solutions to solve this pressing problem,enabling key functionalities such as bacterial growth inhibition,enhanced re-epithelialization,vascularization,improved recovery of the tissue functionality,and overall,accelerated and effective wound healing.

关键词： Wound healing Wound dressing Hydrogel Tissue engineering 3D culture

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A robust subband adaptive filter algorithm for sparse and block-sparse systems identification

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Journal of Systems Engineering and Electronics 2021年第2期32卷 487-497页

作者： ZAHRA Habibi hadi Zayyani MOHAMMAD Shams Esfand Abadi Research Institute for Information and Communications Technologies Academic Center for EducationCulture and ResearchTehran ***Iran Department of Electrical and Computer Engineering Qom University of TechnologyQom 371951519Iran Faculty of Electrical Engineering Shahid Rajaee Teacher Training UniversityTehran ***Iran

This paper presents a new subband adaptive filter(SAF)algorithm for system identification scenario under impulsive interference,named generalized continuous mixed p-norm SAF(GCMPN-SAF)*** proposed algorithm uses a GCMPN cost function to combat the impul-sive *** further accelerate the convergence rate in the sparse and the block-sparse system identification processes,the proportionate versions of the proposed algorithm,the L0-norm GCMPN-SAF(L0-GCMPN-SAF)and the block-sparse GCMPN-SAF(BSGCMPN-SAF)algorithms are also ***,the convergence analysis of the proposed algorithm is *** results show that the proposed algorithms have a better performance than some other state-of-the-art algorithms in the literature with respect to the convergence rate and the tracking capability.

关键词： subband adaptive filter(SAF) generalized continuous mixed p-norm(GCMPN) sparse system block-sparse system impulsive interference

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Optimal control homotopy perturbation method for cancer model

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International Journal of Biomathematics 2019年第3期12卷 79-90页

作者： Malihe Najafi hadi Basirzadeh Department of Mathematics Faculty of Mathematical Sciences and Computer Shahid Chamran University of Ahvaz Ahvaz Iran

In this paper, we introduced the optimal control homotopy perturbation method (OCHPM) by using the homotopy perturbation method (HPM). Every one, by using of the proposed method, can obtain numerical solutions of mathematical modeling for cancer-immunotherapy. In this paper, in order to prove the preciseness and efficiency of the OCHPM method, we compared the obtained numerical solutions with HPM. The results obtained showed that the OCHPM method is powerful to generate the numerical solutions for some therapeutic models.

关键词： Optimal control homotopy perturbation method cancer immunotherapy epidemic models

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Dispersion compensation using high-positive dispersive optical fibers

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Chinese Optics Letters 2017年第3期15卷 64-68页

作者： Mohammand hadi Farokh Marvasti Mohammad Reza Pakravan Electrical Engineering Department Sharif University of Technology Tehran 113658639 Iran

The common and traditional method for optical dispersion compensation is concatenating the transmitting optical fiber by a compensating optical fiber having a high-negative dispersion coefficient. In this Letter, we take the opposite direction and show how an optical fiber with a high-positive dispersion coefficient is used for dispersion compensation. Our optical dispersion compensating structure is the optical implementation of an iterative algorithm in signal processing. The proposed dispersion compensating system is constructed by cascading a number of compensating sub-systems, and its compensation capability is improved by increasing the number of embedded sub-systems. We also show that the compensation capability is a trade-off between the transmission length and bandwidth. We use the simulation results to validate the performance of the introduced dispersion compensating module. Photonic crystal fibers with high-positive dispersion coefficients can be used for constructing the proposed optical dispersion compensating module.

关键词： Dispersion compensation using high-positive dispersive optical fibers high

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Effect of constructing twin tunnels under a building supported by pile foundations in the Sydney central business district

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Underground Space 2019年第4期4卷 261-276页

作者： hadi Khabbaz Robert Gibson Behzad Fatahi School of Civil and Environmental Engineering University of Technology Sydney(UTS)Australia

In congested cities such as Sydney,competition for underground space escalates within the built environment because various assets require finite geotechnical strength and *** problems such as damage to buildings may develop when high-rise buildings on piled foundations are subject to ground movements as tunnels are *** paper focuses on the risks of tunneling beneath Sydney’s Martin Place and how buildings are subject to additional loads caused by *** key objective of this study is to improve the understanding of tunnel-rock-pile interactions and to encourage sustainable development.A finite element model is developed to predict the interaction between tunnel construction and piled *** tunnel,rock,and pile components are studied separately and are then combined into a single *** ground model is based on the characteristics of Hawkesbury Sandstone and is developed through a desktop *** piles are designed using Australian Standards and observations of high-rise *** tunnel construction is modeled based on the construction sequence of a tunnel boring *** combining the components,a parametric study on the relationship between tunnel location,basements,and piles is *** findings,thus far,show that tunneling can increase the axial and flexural loads of piles,where the additional loading exceeds the structural capacity of some piles,especially those that are close to basement *** parametric study reveals a strong relationship between tunnel depth and lining stresses,while the relationship between tunnel depth and induced pile loads is less ***,the horizontal tunnel position relative to piles shows a stronger relationship with pile *** research into tunnel-rock-pile interactions is recommended,especially beneath basements,to substantiate the results of this study.

关键词： Twin tunnels Finite element modeling Pile foundations Plaxis Sydney central business district

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