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Multi-layer spectral clustering approach to intentional islanding in bulk power systems

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Journal of Modern Power Systems and Clean Energy 2019年第5期7卷 1044-1055页

作者： Faycal ZNIDI hamzeh davarikia Kamran IQBAL Masoud BARATI Department of Systems Engineering University of Arkansas at Little RockLittle RockARUSA Department of Electrical and Computer Engineering Louisiana State UniversityBaton RougeLAUSA Department of Electrical and Computer Engineering University of PittsburghPittsburghPAUSA

Intentional controlled islanding(ICI)is a final resort for preventing a cascading failure and catastrophic power system *** paper proposes a controlled islanding algorithm that uses spectral clustering over multilayer graphs to find a suitable islanding *** multi-criteria objective function used in this controlled islanding algorithm involves the correlation coefficients between bus frequency components and minimum active and reactive power flow *** to the previous studies,the algorithm is applied in two *** the first stage,groups of coherent buses are identified with the help of modularity clustering using correlation coefficients between bus frequency *** the second stage,the ICI solution satisfying bus coherency with minimum active and reactive power flow disruptions is determined by grouping all nodes using spectral clustering on the multi-layer *** studies on the IEEE 39-bus test system demonstrate the effectiveness of the method in determining an islanding solution in real time while addressing the generator coherency problem.

关键词： Constrained spectral clustering Controlled islanding Bus coherency Multi-layer graph Normalized spectral clustering

Designing Evolutionary Wavelet Neural Network for Estimating Foaming Slag Quality in Electric Arc Furnace Using Power Quality Indices

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CSEE Journal of Power and Energy Systems 2022年第4期8卷 1165-1174页

作者： hamzeh Rezvani Hamed Khodadadi Department of Electrical Engineering Khomeinishahr BranchIslamic Azad UniversityIsfahanIran

In the present study,a novel approach based on an evolutionary wavelet neural network(EWNN)is proposed to estimate the slag quality in an electric arc furnace(EAF)employing power quality *** the EWNN,an evolutionary method is applied to train the parameters for a combination of neural networks and wavelets.I For this purpose,all of the electrical parameters for six melting processes are measured with a power quality analyzer,attached to the secondary component of an EAF transformer at a Saba steel complex,to estimate the foaming slag *** results on various combinations of measured electrical parameters,applying the designed EWNN estimator,demonstrate that utilizing five leading indicators leads to the highest *** obtained 99%accuracy for estimating the foaming slag quality by EWNN compared to the other methods illustrates the proposed method's efficiency.

关键词： Electric arc furnace(EAF) evolutionary wavelet neural network(EWNN) foaming slag quality power quality analyzer

Knowledge,attitude,and practices toward osteoporosis among Jordanian nurses

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Frontiers of Nursing 2023年第3期10卷 327-333页

作者： Alsalti Zaid Abu Alhaja Eyad Abu Nab hamzeh Department of Nursing Abdali HospitalAmman 11190Jordan Quality Patient Safety and Experience DepartmentAbdali HospitalAmman 11190 Jordan College of Nursing Israa UniversityAmman 11190Jordan

Objective:To identify the level of knowledge,attitude,and practice(KAP)toward osteoporosis among Jordanian ***:A cross-sectional design was adopted in this study.A convenience sample of 443 Jordanian nurses were recruited from the public and private healthcare settings in *** assessment tool used in the current study contained 35 items,measuring KAP among Jordanian nurses toward *** correlation Pearson test and regression test were used to analyze data using Statistical Package for Social Sciences,version ***:The total KAP scores were 33.53,37.65,and 22.7,*** results revealed that Jordanian nurses have a moderate level of KAP toward ***:Jordanian nurses showed a moderate KAP toward osteoporosis,which should be improved as an effective step to reducing the growing incidences of *** lack of KAP holds a serious and growing impact on the Jordanian health sector and patients’health in terms of cost,healthcare resources,and social *** can play a valuable role in educating patients on bone fracture causes,perceived percentage,risks,and prevention,as well as in helping them with nutrition and lifestyle recommendations.

关键词： knowledge attitude practice osteoporosis health belief model

Potassium phthalimide:An efficient and green organocatalyst for the synthesis of 4-aryl-7-(arylmethylene)-3,4,6,7-tetrahydro-1Hcyclopenta[d]pyrimidin-2(5H)-ones/thiones under solvent-free conditions

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Chinese Chemical Letters 2014年第2期25卷 313-316页

作者： hamzeh Kiyani Maryam Ghiasi School of Chemistry Damghan University

An efficient synthesis of Biginelli-type compounds using potassium phthalimide as a green, mild, and commercially available organocatalyst in a one-pot, multi-component cyclocondensation reaction of cyclopentanone, aldehydes, and urea/thiourea is reported. The present methodology is a green approach to access 4-aryl-7-（aryImethylene）-3,4,6,7-tetrahydro-1H-cyclopenta[d]pyrimidin-2（5H）-ones/thiones. It offers several merits such as simple operational procedures, no use of hazardous organic solvents, and cheap and environmentally friendly solid basic catalyst.

关键词： Organocatalyst Potassium phthalimide Biginelli reaction PyrimidinoneSolvent-free

Wellbore stability analysis to determine the safe mud weight window for sandstone layers

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Petroleum Exploration and Development 2019年第5期46卷 1031-1038页

作者： DARVISHPOUR Ayoub CHERAGHI SEIFABAD Masoud WOOD David Anthony GHORBANI hamzeh Department of Mining Engineering Isfahan University of TechnologyIsfahan ***Iran DWA Energy Limited LincolnLN59JPUnited Kingdom Southern Oil Fields National Iranian Oil CompanyTeheran ***Iran

The wellbore stability of a vertical well through the sandstone reservoir layers of the Asmari oil-bearing formation in south-west Iran is *** safe drilling-fluid density range for maintaining wellbore stability is determined and simulated using FLAC3 D software and a finite volume model established with drilled strata geomechanical *** initiation of plastic condition is used to determine the safe mud weight window(SMWW)in specific sandstone *** effects of rock strength parameters,major stresses around the wellbore and pore pressure on the SMWW are investigated for this *** analysis reveals that a reduction in cohesion and internal friction angle values leads to a significant narrowing of the *** the other hand,the reduction of pore pressure and the ratio between maximum and minimum horizontal stresses causes the SMWW to widen *** ability to readily quantify changes in SMWW indicates that the developed model is suitable as a well planning and monitoring tool.

关键词： wellbore stability wellbore geomechanical property safe mud weight window wellbore instability risk factors drilling stress simulation

Numerical modeling of cavitation on spillway＇s flip bucket

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Frontiers of Structural and Civil Engineering 2016年第4期10卷 438-444页

作者： Abbas PARSAIE Sadegh DEHDAR-BEHBAHANI Amir hamzeh HAGHIABI Department of water Engineering Lorestan University Khorramabad Iran Hydro Structures Shahid Chamran University Ahvaz Iran

Numerical modeling of hydraulic phenomenon by computational fluid dynamic （CFD） approaches is one of the main parts in the high cost hydraulic structure studies. In this paper, using Flow 3D as CFD commercial tool, the cavitation phenomenon was assessed along spillway＇s flip bucket of the Balaroud dam. Performance of numerical modeling was compared to the physical model, which was constructed to this purpose. During numerical modeling, it was found that RNG turbulence model is a suitable performance for modeling the cavitation. Physical modeling shows that minimum cavitation index is about 0.85 and minimum cavitation index based on Flow 3D results is about 0.665, which was related to the flood discharge with return period of 10000 years. The main difference between numerical and physical modeling is related to the head of velocity, which is considered in physical modeling. Results of numerical simulation show that occurrence of cavitation based on cavitation index equal to 0.25 is not possible along the spillway.

关键词： cavitation Index numerical simulation spillway's flip Bucket CFD Balaroud Dam physical modeling

Heat Transfer and Energy Analysis of a Pusher Type Reheating Furnace Using Oxygen Enhanced Air for Combustion

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Journal of Iron and Steel Research(International) 2010年第4期17卷 12-17页

作者： hamzeh Jafar Karimi Mohammad Hassan Saidi Science and Research Campus Islamic Azad University School of Mechanical Engineering Sharif University of Technology

Oxy-fuel firing is more energy efficient and environmental friendly than conventional air-fuel firing and its application to reheating furnaces has begun since 1990s. A computational method was presented to predict the steady heat transfer to the billets and temperature distribution in a continuous pusher type reheating furnace in which combustion air was enhanced by oxygen. Radiation heat flux calculated from the radiation heat exchange within the furnace was modeled using the FVM considering the effects of furnace walls and billets. Energy consumption per ton of steel, production rate and thermal efficiency of furnace, and trend of NOx emission in various levels of oxygen enrichment were investigated by comparing with baseline furnace （21% of O2 in air）. The results showed that the best range of oxygen enrichments was between 21% and 45% by volume, as the higher slope of flame temperature and production increase occur in this range. The reduction of energy consumption can be obtained up to 18% per ton of steel for oxygen enrichment of 60 % by volume.

关键词： oxygen enhanced combustion reheating furnace energy consumption

Nanoparticles assisted microwave radiation:Fluid-rock interactions in oil reservoirs

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Petroleum Science 2021年第6期18卷 1797-1812页

作者： hamzeh Shamsi Armandi Arezou Jafari Reza Gharibshahi Faculty of Chemical Engineering Tarbiat Modares UniversityTehranIran

Recently,many researchers have focused on the usage of electromagnetic waves in oil production and well stimulation,but so far the effect of these waves on the fluid and rock interaction and its simultaneous effect with nanoparticles have not been ***-rock interaction is one of the most important factors affecting fluid distribution in the *** this study,the oil reservoir rock wettability alteration under electromagnetic heating and the presence of nanoparticles has been *** nanoparticles of TiO_2,Fe_(3)O_(4),and TiO_2/Fe_(3)O_(4)have been ***_2 nanoparticles are commercially available,and the other mentioned nanoparticles are synthesized via a co-precipitation *** acid has been used to modify surfaces of nanoparticles and stabilize them in water as the base ***,the adsorption of the nanoparticles on the rock surface has been *** the next step,the amount of oil outflow from the rock has been measured and reported as the external fluid *** this process,the nanoparticle performance in wettability alteration was investigated using pH and inductively coupled plasma(ICP)*** better understand the governing mechanisms,oil viscosity was measured by mixing the oil with nanoparticles and put under *** results reveal that the microwave has a great ability to reduce oil contact angle with carbonate *** the presence of0.2 wt%Fe_(3)O_(4)nanoparticles,the contact angle was reduced from 155°to 19°after 28 min of irradiation,indicating strong rock ***,microwave irradiation on Fe_(3)O_(4)nanofluid extracts75%of the oil from the *** microwave radiation,the pH of the nanofluid increases and hence,more nanoparticles are adsorbed on the rock which subsequently causes more rock *** viscosity change results prove that there is an optimal irradiation time of 5 min in which oil viscosity reduces from 481 cP to 410 cP and then increases to 827

关键词： Microwave radiation Wettability alteration Nanoparticle adsorption Rock-fluid interaction

Evaluation of photosynthesis, physiological, and biochemical responses of chickpea (Cicer arietinum L. cv. Pirouz) under water deficit stress and use of vermicompost fertilizer

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Journal of Integrative Agriculture 2018年第11期17卷 2426-2437页

作者： Saeed Reza Hosseinzadeh hamzeh Amiri Ahmad Ismaili Department of Biology Faculty of Basic Sciences Lorestan University Khorramabad PO Box 465 Iran Department of Agronomy and Plant Breeding Faculty of Agriculture Lorestan University Khorramabad PO Box 465 Iran

One goal in the face of drought stress conditions is to increase growth and yield through the reduction of negative effects of stress. Vermicompost can play an effective role in plant growth and development and in reducing harmful effects of various environmental stresses on plants due to its porous structure, high water storage capacity, having hormone-like substances, plant growth regulators, and high levels of macro and micro nutrients. This study considered the physiological, biochemical, and photosynthetic responses of the chickpea to different combinations of vermicompost and water stress in a greenhouse environment. Two factors were involved, addition of vermicompost to soil at four ratios： control （100 wt% （weight percentage） sol0; 10 wt% vermicompost＋90% soil; 20 wt% vermicompost＋80 wt% soil; 30 wt% vermicompost＋70 wt% soil weight percentage, and treatment of water stress at three levels including 75, 50, and 25% of field capacity. The results showed that vermicompost had a significant effect on all traits under stress and non-stress conditions. Application of vermicompost in soil, especially at the levels of 20 and 30 wt% significantly increased all studied traits under non-stress conditions. Under moderate stress conditions, vermicompost at 30 wt% treatment resulted in a significant increase in the photosynthetic pigments, CO2 assimilation rate, internal leaf CO2 concentration, transpiration, the maximal quantum yield of photosystem II （PSII） photochemistry （FJF）, concentrations of Ca and K in root and leaf tissues, proline and soluble protein contents in root tissues. Peroxidase （POX） and catalase （CAT） enzyme activities decreased significantly with increasing proportions of vermicompost, but the activity of superoxide dismutase was not significantly different. In conclusion, the above results showed that vermicompost fertilizer had a positive effect on physiological, biochemical, and photosynthetic responses of chickpea under non-stress and moderate str

关键词： organic fertilizer photosynthetic features water stress gas exchange