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Degradation of a discrete infilled joint shear strength subjected to repeated blast-induced vibrations

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International Journal of Mining Science and Technology 2018年第4期28卷 560-570页

作者： Siamaki Ali Esmaieli kamran Mohanty Bibhu Lassonde Institute of Mining University of Toronto

This paper presents the results of a series of numerical modeling experiments aimed at quantifying blast- induced degradation of shear strength of discontinuities. Near-field vibration history of a single-row pro- duction blast in a. limestone quarry was used as input to the nu .merical model. For this. purpose, two rock blocks, representing a stiff massive sulfide rock and a weaker limestone rock, were simulated using the 2D Particle Flow Code （PFC2D）. Rock mass conta!ning a single inclined joint was modeled as Mohr- Coulomb. The results show that the crack generation rate is increased in both samples after repetitive vibration loading. Joint shear strength degradation rate in !he stiffer massive sulfide rock sample is higher than the softer limestone rock, which is attributed to the higher seismic impedance mismatch. The results show that even low-amplitude blasting vibrations （〈80 mm/s）, when repeated as in multi-hole blasts, can significantly degrade joint shear strength in the nearby pit walls.

关键词： Blasting Vibration PFC2D Discontinuity Rock Degradation

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

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

The power of light and sound:optoacoustic skin imaging for diabetes progression monitoring

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Light(Science & Applications) 2023年第12期12卷 2545-2547页

作者： Amanda P.Siegel kamran Avanaki Richard and Loan Hill Department of Biomedical Engineering University of Illinois at ChicagoChicagoILUSA Section of Neonatology Department of PediatricsUI Health Children’s Hospital of the University of Illinois at ChicagoChicagoILUSA Department of Dermatology University of Illinois at ChicagoChicagoILUSA

Diabetes progression is marked by damage to vascular and neural ***-scan optoacoustic mesoscopy holds the potential to measure extent of diabetes progression by analyzing changes in skin vasculature.

关键词： diabetes damage holds

Diketene-based neat four-component synthesis of the dihydropyrimidinones and dihydropyridine backbones using silica sulfuric acid(SSA)

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Chinese Chemical Letters 2012年第8期23卷 930-932页

作者： Sadegh Rostamnia kamran Lamei Organic and Nano Group(ONG) Department of ChemistryFaculty of ScienceUniversity of MaraghehP.O.Box 55181-83111MaraghehIran

Heterocyclic skeleton building blocks to afford dihydropyrimidinones and dihydropyridines based on neat adducts of diketene, alcohols and aldehydes via silica sulfuric acid （SSA） catalyzed ring opening of diketene i... 详细信息

关键词： Diketene Dihydropyrimidinone Dihydropyridine Heterocyclic skeleton Silica sulfuric acid

A self-routing load balancing algorithm in parallel computing: comparison to the central algorithm

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Journal of Zhejiang University-Science C(Computers and Electronics) 2011年第6期12卷 455-463页

作者： Razieh Sadat SADJADY kamran ZAMANIFAR Department of Computer Engineering Islamic Azad University

Load balancing is an important stage of a system using parallel computing where the aim is the balance of workload among all processors of the system. In this paper, we introduce a new load balancing algorithm with new capabilities for parallel systems, among which is the independence of a separate route-finder algorithm between the load receiver and sender nodes. In addition to simulation of the new algorithm, due to similarity in behavior to the proposed algorithm, the central algorithm is simulated. Simulation results show that, the system performance increases with the increase of the degree of neighborhood between the processors. These results also indicate the algorithm’s high compatibility with environment changes.

关键词： Parallel computing Load balancing Distributed system

A Framework to Assess Possible Sources of Stakeholder Exploitation:A Developing Country Case

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International Journal of Disaster Risk Science 2024年第1期15卷 32-44页

作者： kamran Shafique Syed Shams Tapan Sarker School of Business University of Southern QueenslandSpringfeldQLD 4300Australia Business School University of QueenslandSt LuciaQLD 4072Australia

Solving complex post-disaster reconstruction challenges requires the altruistic involvement of heterogeneous stakeholder ***,small,more organized groups,such as government parastatals,private developers,and contractors often exploit large,unorganized groups,such as affected communities,leaving them more vulnerable to future *** on data collected from a case study in Pakistan,this study proposed a framework to assess,anticipate,and mitigate the exploitation of vulnerable stakeholders in post-disaster reconstruction *** framework draws on influential management theories and utilizes reciprocal relationships between stakeholder attributes(power,legitimacy,and urgency),participation,and *** study also argued for non-binary treatment of stakeholder *** framework will allow practitioners to address issues around the exploitation of stakeholder interests in future post-disaster reconstruction projects.

关键词： Collective action Pakistan Post-disaster reconstruction-Stakeholder participation Stakeholder exploitation