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Improvement of Mining Fuzzy Multiple-Level Association Rules from Quantitative Data

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Journal of Software Engineering and Applications 2012年第3期5卷 190-199页

作者： Alireza Mirzaei Nejad Kousari seyed javad mirabedini Ehsan Ghasemkhani Department of Computer Science Central Tehran Branch Islamic Azad University Tehran Iran Department of Computer Science East Tehran (Ghiamdasht) Branch Islamic Azad University Tehran Iran

Data-mining techniques have been developed to turn data into useful task-oriented knowledge. Most algorithms for mining association rules identify relationships among transactions using binary values and find rules at a single-concept level. Extracting multilevel association rules in transaction databases is most commonly used in data mining. This paper proposes a multilevel fuzzy association rule mining model for extraction of implicit knowledge which stored as quantitative values in transactions. For this reason it uses different support value at each level as well as different membership function for each item. By integrating fuzzy-set concepts, data-mining technologies and multiple-level taxonomy, our method finds fuzzy association rules from transaction data sets. This approach adopts a top-down progressively deepening approach to derive large itemsets and also incorporates fuzzy boundaries instead of sharp boundary intervals. Comparing our method with previous ones in simulation shows that the proposed method maintains higher precision, the mined rules are closer to reality, and it gives ability to mine association rules at different levels based on the user’s tendency as well.

关键词： Association Rule Data Mining Fuzzy Set Quantitative Value Taxonomy

Hydrodynamic modeling strategy for dense to dilute gas-solid fluidized beds

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Particuology 2017年第2期15卷 105-116页

作者： seyed Ahmad Kia javad Aminian Faculty of Mechanical and Energy Engineering Shahid Beheshti University A.C. Tehran Iran

When investigating the hydrodynamic behavior of gas–solid flow systems, there are several options for the drag function, viscosity model, and other parameters. The low accuracy obtained with a random trial and error modeling strategy has led researchers to develop new drag models that are fine-tuned for their specific studies. However, besides the drag functions, an appropriate viscosity model together with radial distribution function have a great impact on the hydrodynamic modeling of fluidized beds. In this study, a detailed validation and verification task is conducted using three different experimental datasets to derive a modeling strategy for predicting hydrodynamic behavior in dense to dilute flow regimes of various fluidized beds. For this purpose, the steady-state Reynolds-averaged Navier–Stokes equations are solved in a finite volume scheme using the twoPhaseEulerFoam solver in the OpenFOAM 2.1.1 software. A comparative study of different drag and viscosity models enables an optimal modeling strategy to be determined for the accurate prediction of the bed pressure drop, bed expansion ratio, time-averaged solid hold-up, and bed height in various dense and dilute flow regimes. Our results show that the modeling strategy prescribed in this study is widely applicable for identifying the hydrodynamic characteristics of various gas–solid fluidized beds with different operating conditions.

关键词： Modeling strategy Hydrodynamic behavior Fluidized bed OpenFOAM Drag-viscosity model

A novel hybrid algorithm based on a harmony search and artificial bee colony for solving a portfolio optimization problem using a mean-semi variance approach

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Journal of Central South University 2016年第1期23卷 181-188页

作者： seyed Mohammad seyedhosseini Mohammad javad Esfahani Mehdi Ghaffari Department of Industrial Engineering Iran University of Science and Technology Young Researchers and Elite Club Naragh BranchIslamic Azad University Department of Industrial Engineering Naragh BranchIslamic Azad University

Portfolio selection is one of the major capital allocation and budgeting issues in financial management, and a variety of models have been presented for optimal selection. Semi-variance is usually considered as a risk factor in drawing up an efficient frontier and the optimal portfolio. Since semi-variance offers a better estimation of the actual risk portfolio, it was used as a measure to approximate the risk of investment in this work. The optimal portfolio selection is one of the non-deterministic polynomial(NP)-hard problems that have not been presented in an exact algorithm, which can solve this problem in a polynomial time. Meta-heuristic algorithms are usually used to solve such problems. A novel hybrid harmony search and artificial bee colony algorithm and its application were introduced in order to draw efficient frontier portfolios. Computational results show that this algorithm is more successful than the harmony search method and genetic algorithm. In addition, it is more accurate in finding optimal solutions at all levels of risk and return.

关键词： portfolio optimizations mean-variance model mean semi-variance model harmony search and artificial bee colony efficient frontier

Photodegradation of reactive blue 19 dye using magnetic nanophotocatalyst α-Fe_(2)O_(3)/WO_(3):A comparison study of α-Fe_(2)O_(3)/WO_(3)and WO_(3)/NaOH

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Water Science and Engineering 2021年第2期14卷 119-128页

作者： Mohammad Delnavaz javad Farahbakhsh seyed Sajad Mahdian Civil Engineering Department Faculty of EngineeringKharazmi UniversityTehran 15719-14911Iran School of Engineering Edith Cowan UniversityJoondalup WA 6027Australia

The photocatalytic degradation of reactive blue 19(RB19)dye was investigated in a slurry system using ultraviolet(UV)and light-emitting diode(LED)lamps as light sources and using magnetic tungsten trioxide nanophotocatalysts(α-Fe_(2)O_(3)/WO_(3)and WO_(3)/NaOH)as *** effects of different parameters including irradiation time,initial concentration of RB19,nanophotocatalyst dosage,and pH were *** magnetic nanophotocatalysts were also characterized with different methods including scanning electron microscopy(SEM),energy-dispersive X-ray spectroscopy(EDS),transmission electron microscopy(TEM),X-ray diffraction(XRD),photoluminescence(PL),differen-tial reflectance spectroscopy(DRS),Fourier transform infrared spectroscopy(FTIR),and vibrating sample magnetometry(VSM).The XRD and FTIR analyses confirmed the presence of tungsten trioxide on the iron oxide *** VSM analysis confirmed the magnetic ability of the new synthesized nanophotocatalyst α-Fe_(2)O_(3)/WO_(3)with 39.6 emu/g of saturation *** reactor performance showed consid-erable improvement in the α-Fe_(2)O_(3)-modified *** impact of visible light was specifically investigated,and it was compared with UV-C light under the same experimental *** reusability of the magnetic nanophotocatalyst α-Fe_(2)O_(3)/WO_(3)was tested during six cycles,and the magnetic materials showed an excellent removal efficiency after six cycles,with just a 7%decline.

关键词： Reactive blue 19 Magnetic nanophotocatalyst a-Fe_(2)O_(3)/WO_(3) Saturation magnetization UV-C lamps

Experimental Investigation and Semi-Active Control Design of A Magnetorheological Engine Mount

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Sound & Vibration 2019年第6期53卷 297-308页

作者： seyed Salman Hosseini javad Marzbanrad School of Automotive Engineering Iran University of Science and TechnologyTehranIran Faculty at School of Automotive Engineering Iran University of Science and TechnologyTehranIran

In this paper;the dynamic characteristics of a semi-active magnetorheological fluid(MRF)engine mount are *** do so,the performance of the MRF engine mount is experimentally examined in higher frequencies(50~170 Hz)and the various amplitudes(0.01~0.2 mm).In such an examination,an MRF engine mount along with its magnetically biased is fabricated and successfully *** addition,the natural frequencies of the system are obtained by standard hammer modal *** modelling the behavior of the system,a mass-spring-damper model with tuned PID coefficients based on Pessen integral of absolute error method is *** parameters of such a model including mass,damping ratio,and stiffness are identified with the help of experimental modal tests and the recursive least square method(RLS).It is shown that using PID controller leads to reducing the vibration transmissibility in the resonance frequency(=93.45 Hz)with respect to the typical passive engine mount by a factor of 58%.The average of the vibration transmissibility decreasing is also 43%within frequency bandwidth(50~170 Hz).

关键词： Semi-active engine mount PID controller experimental data least square method magnetorheological fluid

Numerical study of aerosol particle deposition in simple and converging-diverging micro-channels with a slip boundary condition at the wall

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Particuology 2014年第2期12卷 100-105页

作者： seyed Mohammad javad Hosseini Ataallah Soltani Goharrizi Bahador Abolpour Department of Chemical Engineering Faculty of EngineeringShahid Bahonar University of Kerman

The design of micro-devices involving aerosol transport requires the study of the deposition of aerosols in micro-channels. In this study, the slip and no-slip boundary conditions for the gas flow regime were applied to the Navier-Stokes equations to obtain the particle deposition in simple and converging-diverging micro-channels. The equation of particle motion included inertial, viscous, Brownian, and gravity terms. It was found that the ratio of gravity to inertial effects controls the deposition of particles with diameters of 0.1-1 μm, and the ratio of diffusion to inertial effects controls the deposition of particles with diameters of 0.01-0.001 i^m. Comparison between the no-slip and slip flow regimes showed that the deposition of 0.1- to 1-μm-diameter particles was less and the deposition of 0.01- to 0.001-1μm-diameter particles was greater for the slip flow regime. There was no significant difference between slip and no-slip flow regimes for the deposition of 0.01- to 0.1-μm-diameter particles. Finally, it was shown that the stagnated gas in the corners of the converging-diverging micro-channel produced similar gas velocity profiles under the slip and no-slip flow regimes.

关键词： Aerosol depositionMicro-channelConverging-diverging micro-channelSlip boundary condition

A simple granulation technique for preparing high-porosity nano copper oxide(Ⅱ) catalyst beads

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Particuology 2011年第5期9卷 480-485页

作者： seyed javad Ahmadi Mohammad Outokesh Morteza Hosseinpour Tahereh Mousavand Jaber Ebne Hayyan Research Laboratory School of Energy Engineering Sharif University of Technology Department of Mechanical Engineering McGill University

A simple and efficient method was developed for fabricating spherical granules of CuO catalyst via a three-step procedure. In the first step, copper oxide nanoparticles were synthesized by hydrothermal decomposition of copper nitrate solution under supercritical condition. Then, they were immobilized in the polymeric matrix of calcium alginate, and followed by high-temperature calcination in an air stream as the third step, in which carbonaceous materials were oxidized, to result in a pebble-type catalyst of high porosity. The produced CuO nanoparticles were characterized by transmission electron microscopy （TEM） that revealed an average size of 5 nm, X-ray diffractometry （XRD）, and thermo gravimetric （TG） analysis. The catalysts were further investigated by BET test for measurement of their surface area, and by temperature-programmed reduction analysis （H2-TPR） for determination of catalytic activity. The results demonstrated that immobilization of the CuO nanoparticle in the polymeric matrix of calcium alginate, followed by calcination at elevated temperatures, could result in notable mechanical strength and enhanced catalytic activity due to preservation of the high surface area, both valuable for practical applications.

关键词： CuO nanoparticles Catalyst Hydrothermal synthesis Supercritical water Granulation Calcium alginate

Irrigation effects on diameter growth of 2-year-old Paulownia tomentosa saplings

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Journal of Forestry Research 2015年第1期26卷 153-157页

作者： javad Eshaghi Rad seyed Rostam Mousavi Mirkala Department of Forestry Faculty of Natural ResourcesUrmia University

Species of Paulownia are fast-growing trees that are planted in many countries in green spaces and agroforestry systems. We studied the influence of irrigation on the diameter growth of 2-year-old Paulownia tomentosa saplings planted in 3 m 9 3 m grids at Nazlou Campus of Urmia University, Iran. Completely randomized experimental design was used with four irrigation amount, viz.10, 15, 20 and 25 L, and three irrigation intervals, viz. 3-and 6-days, in 8 replications. During the growth season, we measured collar diameters of all saplings at the end of each month. Diameter growth declined with reduced irrigation amount and increased irrigation interval. The lowest average diameter growth（9 mm） was recorded for 10 L water at 6-day intervals and maximum average diameter growth（28.7 mm） was recorded for 25 L volume at 3-day intervals. The latter treatment resulted in significantly greater diameter growth than any other treatment（except20 L at 3-day intervals）. More than 80 % of diameter growth was achieved in the first 3 months. Therefore, it is essential to irrigate with 25 L of water at 3-day intervals during the first three growth months to achieve maximum diameter growth for 2-year-old P. tomentosa saplings.

关键词： Paulownia tomentosa Diameter growth Irrigation interval Iran

Commentary regarding “on-orbit sleep problems of astronauts and countermeasures”

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Military Medical Research 2019年第2期6卷 178-182页

作者： Joseph John Bevelacqua seyed Mohammad javad Mortazavi Bevelacqua Resources 343Adair DriveRichland WA99352USA Department of Electrical Engineering Biophotonics LabUniversityof Wisconsin Milwaukee3200N Cramer StMilwaukee WI53211USA Doss Lab(R-432) Fox Chase Cancer Center333Cottman AvenuePhiladelphia PA19111USA

This commentary addresses the article by Wu et al. entitled 'On-orbit sleep problems of astronauts and countermeasures'. In this article, the authors discussed the sleep problems of astronauts. Despite its challenging topic, the paper authored by Wu et al. has at least one major shortcoming. This issue is related to the observation that the sleep pattern of astronauts can be disturbed by light flash phenomenon. Since the first report by astronaut E.E. Aldrin in 1969, many astronauts have reported light flashes. These visually perceived flashes of light occurred in different shapes but they apparently moved across the visual field of astronauts and possibly caused, at least to some extent, sleep problems. Moreover, the countermeasures proposed by the authors may improve astronauts’ sleep pattern, but they do not address the root cause of the light flashes(i.e., heavy ion interactions outside the shielding provided by the Earth’s magnetosphere). A possible approach to reducing light flashes is available using the fact that much of the galactic cosmic radiation(GCR) spectrum is composed of ions that can be diverted from the spacecraft using electromagnetic fields. Possible design parameters and the requisite electric and magnetic field strengths to successfully deflect GCR radiation are outlined.

关键词： Space radiation Astronauts Sleep problems Light flashes Phosphenes