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An improved semi-implicit direct kinetics method for transient analysis of nuclear reactors

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Nuclear Science and Techniques 2019年第11期30卷 108-126页

作者： Roozbeh Vadi kamran Sepanloo School of Nuclear Reactors and Safety Nuclear Science and Technology Research Institute

Semi-implicit direct kinetics(SIDK)is an innovative method for the temporal discretization of neutronic equations proposed by *** key approximation of the SIDK method is to substitute a timeaveraged quantity for the fission source term in the delayed neutron differential ***,these equations are decoupled from prompt neutron equations and an explicit analytical representation of precursor groups is obtained,which leads to a significant reduction in computational *** the fission source is not known in a time step,the original study suggested using a constant quantity pertaining to the previous time step for this purpose,and a reduction in the size of the time step was proposed to lessen the imposed ***,this remedy notably diminishes the main advantage of the SIDK *** discerned that if the original method is properly introduced into the algorithm of the point-implicit solver along with some modifications,the mentioned drawbacks will be mitigated *** test this idea,a novel multigroup,multi-dimensional diffusion code using the finitevolume method and a point-implicit solver is developed which works in both transient and steady *** addition to the SIDK,two other kinetic methods,i.e.,direct kinetics and higher-order backward discretization,are programmed into the diffusion code for comparison with the proposed *** final code is tested at different conditions of two well-known transient benchmark *** indicate that while the accuracy of the improved SIDK is closely comparable with the best available kinetic methods,it reduces the total time required for computation by up to 24%.

关键词： Nuclear kinetics Semi-implicit direct kinetics Higher-order backward discretization Finite volume Point-implicit solver

The impact of climatic variables on the population dynamics of the main malaria vector, Anopheles stephensi Liston(Diptera: Culicidae), in southern Iran

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Asian Pacific Journal of Tropical Medicine 2020年第10期13卷 448-455页

作者： Madineh Abbasi Abbas Rahimi Foroushani Tohid Jafari-Koshki kamran Pakdad Hassan Vatandoost Ahmad ali Hanafi-Bojd Deparment of Medical Entomology&Vector Control School of Public HealthTehran University of Medical SciencesTehranIran Infectious and Tropical Diseases Research Center Tabriz University of Medical SciencesTabrizIran Department of Epidemiology and Biostatistics School of Public HealthTehran University of Medical SciencesTehranIran Molecular Medicine Research Center Tabriz University of Medical SciencesTabrizIran Department of Statistics and Epidemiology Faculty of HealthTabriz University of Medical SciencesTabrizIran Department of Parasitology&Mycology Paramedical SchoolShahid Beheshti University of Medical SciencesTehranIran

Objective:To determine the significance of temperature,rainfall and humidity in the seasonal abundance of Anopheles stephensi in southern ***:Data on the monthly abundance of Anopheles stephensi larvae and adults were gathered from earlier studies conducted between 2002 and 2019 in malaria prone areas of southeastern *** data for the studied counties were obtained from climatology *** estimating equations method was used for cluster correlation of data for each study site in different ***:A significant relationship was found between monthly density of adult and larvae of Anopheles stephensi and precipitation,max temperature and mean temperature,both with simple and multiple generalized estimating equations analysis(P<0.05).But when analysis was done with one month lag,only relationship between monthly density of adults and larvae of Anopheles stephensi and max temperature was significant(P<0.05).Conclusions:This study provides a basis for developing multivariate time series models,which can be used to develop improved appropriate epidemic prediction systems for these ***-term entomological study in the studied sites by expert teams is recommended to compare the abundance of malaria vectors in the different areas and their association with climatic variables.

关键词： Anopheles stephensi Climatic variables Monthly activity Iran

Effects of uniconazole with or without micronutrient on the lignin biosynthesis,lodging resistance,and winter wheat production in semiarid regions

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Journal of Integrative Agriculture 2020年第1期19卷 62-77页

作者： Irshad AHMAD MENG Xiang-ping Muhammad kamran Shahzad ali Shakeel AHMAD LIU Tie-ning CAI Tie HAN Qing-fang Key Laboratory of Crop Physio-Ecology and Tillage Science in North-Western Loess Plateau Ministry of Agriculture/College of AgronomyNorthwest A&F UniversityYangling 712100P.R.China Key Laboratory of Agricultural Soil and Water Engineering in Arid and Semiarid Areas Ministry of Education/Institute of Water Saving Agriculture in Arid Areas of ChinaNorthwest A&F UniversityYangling 712100P.R.China

Lodging stress results in grain yield and quality reduction in wheat. Uniconazole, a potential plant growth regulator significantly enhances lignin biosynthesis and thus provides mechanical strength to plants in order to cope with lodging stress. A field study was conducted during the 2015–2016 and 2016–2017 growing seasons, to investigate the effects of uniconazole sole application or with micronutrient on the lignin biosynthesis, lodging resistance, and production of winter wheat. In the first experiment, uniconazole at concentrations of 0(CK), 15(US1), 30(US2), and 45(US3) mg L^-1 was applied as sole seed soaking, while in the second experiment with manganese(Mn) at concentration of 0.06 g L^-1 Mn, 0.06 g L^-1 Mn+ 15 mg L^-1 uniconazole(UMS1), 0.06 g L^-1 Mn+30 mg L^-1 uniconazole(UMS2), and 0.06 g L^-1 Mn+45 mg L^-1 uniconazole(UMS3), respectively. Uniconazole sole application or with micronutrient significantly increased the lignin content by improving the lignin-related enzyme activities of phenylalanine ammonia-lyase, cinnamyl alcohol dehydrogenase, tyrosine ammonialyase, and peroxidase, ameliorating basal internode characteristics, and breaking strength. The spike length, spike diameter, spikes/plant, weight/spike, yield/spike, and grain yield increased and then decreased with uniconazole application at a higher concentration, where their maximum values were recorded with UMS2 and US2 treatments. The lignin accumulation was positively correlated with lignin-related enzyme activities and breaking strength while, negatively correlated with lodging rate. Uniconazole significantly improved the lignin biosynthesis, lodging resistance, and grain yield of winter wheat and the treatments which showed the greatest effects were uniconazole seed soaking with micronutrient at a concentration of 30 mg L^-1 and 0.06 g L^-1 , and uniconazole sole seed soaking at a concentration of 30 mg L^-1 .

关键词： lignin biosynthesis lodging resistance semi-arid regions manganese uniconazole wheat

SOME RESULTS ON CONTROLLED FRAMES IN HILBERT SPACES

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Acta Mathematica Scientia 2016年第3期36卷 655-665页

作者： kamran MUSAZADEH Hassan KHANDANI Department of Mathematics College of ScienceMahabad BranchIslamic Azad University

We use two appropriate bounded invertible operators to define a controlled frame with optimal frame bounds. We characterize those operators that produces Parseval controlled frames also we state a way to construct nearly Parseval controlled frames. We intro- duce a new perturbation of controlled frames to obtain new frames from a given one. Also we reduce the distance of frames by appropriate operators and produce nearly dual frames from two given frames which are not dual frames for each other.

关键词： frames Parseval frames dual frames controlled frames reconstruction formula perturbation

Novel Fractal-Based Features for Low-Power Appliances in Non-Intrusive Load Monitoring

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Computers, Materials & Continua 2024年第7期80卷 507-526页

作者： Anam Mughees Muhammad kamran Department of Electrical Engineering University of Engineering and Technology(UET)Lahore54890Pakistan Department of Electrical Engineering Government College UniversityFaisalabad38000Pakistan Department of Electrical Engineering and Technology Muhammad Nawaz Sharif University of Engineering&Technology(MNS UET)Multan60000Pakistan

Non-intrusive load monitoring is a method that disaggregates the overall energy consumption of a building to estimate the electric power usage and operating status of each appliance *** studies have mostly concentrated on the identification of high-power appliances like HVAC systems while overlooking the existence of low-power ***-power consumer appliances have comparable power consumption patterns,which can complicate the detection task and can be mistaken as *** research tackles the problem of classification of low-power appliances and uses turn-on current transients to extract novel features and develop unique appliance signatures.A hybrid feature extraction method based on mono-fractal and multi-fractal analysis is proposed for identifying low-power *** dimension,Hurst exponent,multifractal spectrum and the Hölder exponents of switching current transient signals are extracted to develop various‘turn-on’appliance signatures for *** classifiers,i.e.,deep neural network,support vector machine,decision trees,and K-nearest neighbours have been optimized using Bayesian optimization and trained using the extracted *** simulated results showed that the proposed method consistently outperforms state-of-the-art feature extraction methods across all optimized classifiers,achieving an accuracy of up to 96%in classifying low-power appliances.

关键词： Nonintrusive load monitoring multi-fractal analysis appliance classification switching transients

An Efficient Connectivity Restoration Technique(ECRT)for Wireless Sensor Network

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Computers, Materials & Continua 2021年第10期69卷 1003-1019页

作者： Mahmood ul Hassan Shahzad ali Khalid Mahmood Muhammad Kashif Saeed Amin Al-Awady kamran Javed Ansar Munir Shah Department of Computer Skills Preparatory yearNajran UniversityNajran66241Saudi Arabia Department of Computer Science Jouf UniversityTubarjal74769Saudi Arabia Department of Information Systems College of Science and ArtsKing Khalid UniversityMahayil Asir63317Saudi Arabia Department of Computer Science Community College Mahayil AsirKing Khalid UniversityMahayil63718Saudi Arabia Department of Computer Engineering National University of Technology(NUTECH)Islamabad44000Pakistan Department of Computer Science Institute of Southern PunjabMultan60000Pakistan

Node failure in Wireless Sensor Networks(WSNs)is a fundamental problem because WSNs operate in hostile *** failure of nodes leads to network partitioning that may compromise the basic operation of the sensor *** deal with such situations,a rapid recovery mechanism is required for restoring inter-node *** to the immense importance and need for a recovery mechanism,several different approaches are proposed in the ***,the proposed approaches have shortcomings because they do not focus on energy-efficient operation and coverage-aware mechanisms while performing connectivity ***,most of these approaches rely on the excessive mobility of nodes for restoration connectivity that affects both coverage and energy *** paper proposes a novel technique called ECRT(Efficient Connectivity Restoration Technique).This technique is capable of restoring connectivity due to single and multiple node *** achieves energy efficiency by transmitting a minimal number of control *** is also coverage-aware as it relocates minimal nodes while trying to restore *** the help of extensive simulations,it is proven that ECRT is effective in connectivity restoration for single and multiple node *** also show that ECRT exchanges a much smaller number of packets than other ***,it also yields the least reduction in field coverage,proving its versatility for connectivity restoration.

关键词： Cut-vertex failure recovery network connectivity node relocation wireless sensor network node failures

Preliminary design and optimization of slotted tube grain for solid rocket motor

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航空动力学报 2008年第12期23卷 2332-2340页

作者： K Nisar LIANG Guo-zhu A kamran School of Astronautics Beijing University of Aeronautics and Astronautics Beijing 100191 China

In this paper,design and optimization technique of slotted tube grain for solid rocket motors has been *** doing so,the design objectives and constraints have been set,geometric parameters identified,performance prediction parameters calculated,thereafter preliminary designs completed and finally optimal design *** model for slotted tube grain configuration has been *** thrust has been taken as the objective function with constraints of burning time,mass of propellant,fixed length and diameter of chamber *** parameter method has been used for calculating the performance prediction parameters.A set of preliminary designs has been completed and an analysis of these results *** all the preliminary results fulfill the design requirements in terms of objective function and constraints,however in order to attain the optimal design,Sequential quadratic programming optimization technique has been *** the slotted tube grain geometry is totally dependent upon various independent variables and each of these variables has a bearing on explicit characteristic of grain designing,hence affects of the independent variables on performance parameters have been examined,thus variation laws have been *** on the variation laws and the analysis of preliminary design results,upper and lower limits have been defined for the independent geometric variables and an initial guess provided for conducting *** attained exhibits that an optimal result has been attained and the value of objective function has been *** the design constraint limits have also been met while ensuring sound values of volumetric loading fraction,web fraction and *** methodology of design and optimization of slotted tube grain for solid rocket motors can be used by engineers as a reference guide for actual design and engineering purposes.

关键词：固体火箭发动机动力系统设计方案

Experimental investigation into effects of the natural polymer and nanoclay particles on the EOR performance of chemical flooding in carbonate reservoirs

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Petroleum Science 2024年第2期21卷 951-961页

作者： Amir Mohammad Zamani Ashkan Moslemi kamran Hassani Department of Petroleum Engineering Islamic Azad University Science and Research BranchTehranIran Institute of Petroleum Engineering University of TehranTehranIran

This paper aims to investigate the tragacanth gum potential as a natural polymer combined with natural clay mineral(montmorillonite,kaolinite,and illite)nanoparticles(NPs)to form NP-polymer suspension for enhanced oil recovery(EOR)in carbonate *** gravimetric analysis(TGA)tests were conducted initially in order to evaluate the properties of tragacanth ***,scanning electron microscopy(SEM)and energy-dispersive X-ray(EDX)tests were used to detect the structure of clay *** various scenarios,the effects of natural NPs and polymer on the wettability alteration,interfacial tension(IFT)reduction,viscosity improvement,and oil recovery were investigated through contact angle system,ring method,Anton Paar viscometer,and core flooding tests,*** entire experiment was conducted at 25,50,and 75℃,*** to the experimental results,the clay minerals alone did not have a significant effect on viscosity,but the addition of minerals to the polymer solution leads to the viscosity enhancement remarkably,resulting mobility ratio *** clay NPs,the combination of natural polymer and kaolinite results in increased viscosity at all *** wettability alteration was also observed in the case of natural polymer and illite *** in combination with natural polymer showed an ability in reducing ***,the results of displacement experiments revealed that the combination of natural polymer and kaolinite could be the best option for EOR due to its substantial ability to improve the recovery factor.

关键词： Chemical flooding Tragacanth gum Clay nanoparticle Wettability IFT

A model to determine hole spacing in the rock fracture process by non-explosive expansion material

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International Journal of Minerals,Metallurgy and Materials 2011年第5期18卷 509-514页

作者： Shobeir Arshadnejad kamran Goshtasbi Jamshid Aghazadeh Department of Mining Engineering Mahallat BranchIslamic Azad UniversityMahallat ***Iran Department of Mining Engineering Tarbiat Modares UniversityTehran 14115-143Iran Department of Mining and Metallurgical Engineering Amirkabir University of TechnologyTehran ***Iran

The application of the non-explosive expansion material （NEEM） is widely used as the controlled fracture method in quarry min- ing, especially in hard rocks. The pressure of NEEM is an important parameter in causing rock fracture. An empirical model based on hole spacing was developed to determine the pressure of NEEM in the rock fracture process. Primarily, the empirical model was developed by the mathematical method, utilizing dimensional analysis. Then, the Phase2 code, which is based on the finite element method, was utilized to predict crack growth in rocks. The results of numerical analysis show slight deviations from the empirical model. Hence, the polynomial re- gression analysis was used to modify the model. Finally, the modified model shows a good agreement with the results gained from numerical modeling.

关键词： rock fracture dimensional analysis finite element method non-explosive quarry mining