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Type-I Heavy-Tailed Burr XII Distribution with Applications to Quality Control,Skewed Reliability Engineering Systems and Lifetime Data
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作者 Okechukwu J.Obulezi Hatem E.Semary +4 位作者 Sadia Nadir Chinyere P.Igbokwe Gabriel O.Orji A.S.Al-Moisheer Mohammed Elgarhy 《Computer Modeling in Engineering & Sciences》 2025年第9期2991-3027,共37页
This study introduces the type-I heavy-tailed Burr XII(TIHTBXII)distribution,a highly flexible and robust statistical model designed to address the limitations of conventional distributions in analyzing data character... This study introduces the type-I heavy-tailed Burr XII(TIHTBXII)distribution,a highly flexible and robust statistical model designed to address the limitations of conventional distributions in analyzing data characterized by skewness,heavy tails,and diverse hazard behaviors.We meticulously develop the TIHTBXII’s mathematical foundations,including its probability density function(PDF),cumulative distribution function(CDF),and essential statistical properties,crucial for theoretical understanding and practical application.A comprehensive Monte Carlo simulation evaluates four parameter estimation methods:maximum likelihood(MLE),maximum product spacing(MPS),least squares(LS),and weighted least squares(WLS).The simulation results consistently show that as sample sizes increase,the Bias and RMSE of all estimators decrease,with WLS and LS often demonstrating superior and more stable performance.Beyond theoretical development,we present a practical application of the TIHTBXII distribution in constructing a group acceptance sampling plan(GASP)for truncated life tests.This application highlights how the TIHTBXII model can optimize quality control decisions by minimizing the average sample number(ASN)while effectively managing consumer and producer risks.Empirical validation using real-world datasets,including“Active Repair Duration,”“Groundwater Contaminant Measurements,”and“Dominica COVID-19 Mortality,”further demonstrates the TIHTBXII’s superior fit compared to existing models.Our findings confirm the TIHTBXII distribution as a powerful and reliable alternative for accurately modeling complex data in fields such as reliability engineering and quality assessment,leading to more informed and robust decision-making. 展开更多
关键词 Acceptance sampling heavy-tailed models parameter estimation reliability engineering
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Evaluation of micro-dispersion on oil recovery during low-salinity water-alternating-CO_(2)processes in sandstone cores:An integrated experimental approach
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作者 Jia-Xin Wang Leng Tian +5 位作者 Can Huang Xiao-Jiao Deng Daoyong Tony Yang Rui-Heng Wang Jia-Hao Lin Jin-Yang Wei 《Petroleum Science》 2025年第1期277-295,共19页
Low-salinity water(LSW)and CO_(2) could be combined to perform better in a hydrocarbon reservoir due to their synergistic advantages for enhanced oil recovery(EOR);however,its microscopic recovery mechanisms have not ... Low-salinity water(LSW)and CO_(2) could be combined to perform better in a hydrocarbon reservoir due to their synergistic advantages for enhanced oil recovery(EOR);however,its microscopic recovery mechanisms have not been well understood due to the nature of these two fluids and their physical reactions in the presence of reservoir fluids and porous media.In this work,well-designed and inte-grated experiments have been performed for the first time to characterize the in-situ formation of micro-dispersions and identify their EOR roles during a LSW-alternating-CO_(2)(CO_(2)-LSWAG)process under various conditions.Firstly,by measuring water concentration and performing the Fourier transform infrared spectroscopy(FT-IR)analysis,the in-situ formation of micro-dispersions induced by polar and acidic materials was identified.Then,displacement experiments combining with nuclear magnetic resonance(NMR)analysis were performed with two crude oil samples,during which wettability,interfacial tension(IFT),CO_(2) dissolution,and CO_(2) diffusion were quantified.During a CO_(2)-LSWAG pro-cess,the in-situ formed micro-dispersions dictate the oil recovery,while the presence of clay minerals,electrical double-layer(EDL)expansion and multiple ion exchange(MIE)are found to contribute less.Such formed micro-dispersions are induced by CO_(2) via diffusion to mobilize the CO_(2)-diluted oil,alter the rock wettability towards more water-wet,and minimize the density contrast between crude oil and water. 展开更多
关键词 Low-salinity water-alternating-CO_(2)process Micro-dispersion Wettability alteration Clay minerals Electrical double-layer Multiple ion exchange
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A novel dandelion-based bionic proppant and its transportation mechanism in different types of fractures
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作者 Jun Li Ming-Yi Wu +2 位作者 Xu Han Si-Yuan He Ze-Yu Lin 《Petroleum Science》 SCIE EI CAS CSCD 2024年第4期2583-2599,共17页
Low-permeability reservoirs are generally characterized by low porosity and low permeability.Obtaining high production using the traditional method is technologically challenging because it yields a low reservoir reco... Low-permeability reservoirs are generally characterized by low porosity and low permeability.Obtaining high production using the traditional method is technologically challenging because it yields a low reservoir recovery factor.In recent years,hydraulic fracturing technology is widely applied for efficiently exploiting and developing low-permeability reservoirs using a low-viscosity fluid as a fracturing fluid.However,the transportation of the proppant is inefficient in the low-viscosity fluid,and the proppant has a low piling-up height in fracture channels.These key challenges restrict the fluid(natural gas or oil)flow in fracture channels and their functional flow areas,reducing the profits of hydrocarbon exploitation.This study aimed to explore and develop a novel dandelion-bionic proppant by modifying the surface of the proppant and the fiber.Its structure was similar to that of dandelion seeds,and it had high transport and stacking efficiency in low-viscosity liquids compared with the traditional proppant.Moreover,the transportation efficiency of this newly developed proppant was investigated experimentally using six different types of fracture models(tortuous fracture model,rough fracture model,narrow fracture model,complex fracture model,large-scale single fracture model,and small-scale single fracture model).Experimental results indicated that,compared with the traditional proppant,the transportation efficiency and the packing area of the dandelion-based bionic proppant significantly improved in tap water or low-viscosity fluid.Compared with the traditional proppant,the dandelionbased bionic proppant had 0.1-4 times longer transportation length,0.3-5 times higher piling-up height,and 2-10 times larger placement area.The newly developed proppant also had some other extraordinary features.The tortuosity of the fracture did not influence the transportation of the novel proppant.This proppant could easily enter the branch fracture and narrow fracture with a high packing area in rough surface fractures.Based on the aforementioned characteristics,this novel proppant technique could improve the proppant transportation efficiency in the low-viscosity fracturing fluid and increase the ability of the proppant to enter the secondary fracture.This study might provide a new solution for effectively exploiting low-permeability hydrocarbon reservoirs. 展开更多
关键词 Dandelion-based bionic proppant Low-viscosity fracturing fluid Unconventional reservoir Volumetric fracturing stimulation
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Sustainable Circulating Energy System for Carbon Capture Usage and Storage(CCUS)
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作者 Kenji Sorimachi Toshinori Tsukada Hossam A.Gabbar 《Energy Engineering》 2025年第6期2177-2185,共9页
Recently,we developed an innovative CO_(2)capture and storage method based on simple chemical reactions using NaOH and CaCl_(2).In this technology,it was newly found that the addition of CO_(2)gas produced CaCO_(3)(li... Recently,we developed an innovative CO_(2)capture and storage method based on simple chemical reactions using NaOH and CaCl_(2).In this technology,it was newly found that the addition of CO_(2)gas produced CaCO_(3)(limestone)in the solution of NaOH and CaCl_(2)at less than 0.2 N NaOH,while at more than 0.2 N NaOH,Ca(OH)_(2)formation occurred merely without CO_(2).The present study has been designed to develop an integrated system in which the electrolysis unit is combined with the CO_(2)fixation unit.As the electrolysis of NaCl produces simultaneously not only electricity but also H_(2)and Cl_(2),the produced H_(2)could be supplied to the hydrogen generator to produce further electricity,which could be used for the initial NaCl electrolysis for NaOH production.Contrarily,the combination of incinerators with electrolytic generators has already been established to supply electricity,as thermal power plants use coals or wastes.This electricity-providing unit could be replaced with a solar panel plant or with a storage buttery.The present integrated system,consisting of various electricity-providing methods and CO_(2)fixation units,is a sustainable circulating energy system and carbon capture,usage,and storage(CCUS)system without environmental concerns.In addition,an unexpected-tremendous amount of the burned wood,which was produced by the big mountain or forest fires,could be disposed of by our integrated CO_(2)fixing system with the incinerator without environmental concerns along with both H_(2)and CaCO_(3)productions.Thus,our simple technology must contribute immediately and economically to disaster recovery. 展开更多
关键词 CO_(2)fixation CO_(2)storage circular energy system climate change limestone(CaCO_(3)) ELECTROLYSIS CCUS SDGs sustainability
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Acetylation of Corn Stalk(Zea mays)for Its Valorization
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作者 Jhony César Muñoz Zambrano Douglas Alexander Bermúdez Parrales María Antonieta Riera 《Journal of Polymer Materials》 2025年第3期837-851,共15页
Agricultural waste is a potentially interesting resource due to the compounds present.In this study,cellulose was extracted from corn stalks(Zea mays)and subsequently converted into cellulose acetate(CA).Before the ex... Agricultural waste is a potentially interesting resource due to the compounds present.In this study,cellulose was extracted from corn stalks(Zea mays)and subsequently converted into cellulose acetate(CA).Before the extraction process,the waste sample was characterized by pH,moisture,ash,protein content,total reducing sugars(TRS),carbohydrates,cellulose,hemicellulose,and lignin.Acid and alkaline hydrolysis were performed with different reagents,concentrations,and extraction times.Sulfuric acid(H_(2)SO_(4))and acetic acid(CH_(3)COOH)were used in the acid hydrolysis,while sodium hydroxide(NaOH)was used in the alkaline hydrolysis.Three concentrations(0.62,1.25,2.5)%and two reaction times(60,120)min were established.An ANOVA was performed on the hydrolysis results to determine the existence of significant differences.The extracted cellulose was revalued by acetylation,and finally,the CA was characterized by Fourier Transform Infrared Spectroscopy(FT-IR)spectroscopy.The highest cellulose extraction yield was obtained by alkaline hydrolysis,with an extraction time of 120 min and a yield of 65%.The statistical analysis indicated that the reagent used,its concentration,reaction time,and their interaction significantly affect the process yield.After obtaining CA and performing an infrared analysis of the compound’s structure,it was determined that the byproduct corresponds to CA,demonstrating the possibility of revaluing the waste through the studied process.Future studies could improve the results obtained here to promote the development of biobased products within a circular economy framework. 展开更多
关键词 BIOMASS cellulose acetate(CA) lignocellulosic waste waste recovery
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Investigation of active vibration drilling using acoustic emission and cutting size analysis 被引量:4
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作者 Yingjian Xiao Charles Hurich +1 位作者 John Molgaard Stephen D.Butt 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2018年第2期390-401,共12页
This paper describes an investigation of active bit vibration on the penetration mechanisms and bit-rock interaction for drilling with a diamond impregnated coring bit. A series of drill-off tests(DOTs) were conducted... This paper describes an investigation of active bit vibration on the penetration mechanisms and bit-rock interaction for drilling with a diamond impregnated coring bit. A series of drill-off tests(DOTs) were conducted where the drilling rate-of-penetration(ROP) was measured at a series of step-wise increasing static bit thrusts or weight-on-bits(WOBs). Two active DOTs were conducted by applying 60 Hz axial vibration at the bit-rock interface using an electromagnetic vibrating table mounted underneath the drilling samples, and a passive DOT was conducted where the bit was allowed to vibrate naturally with lower amplitude due to the compliance of the drilling sample mountings. During drilling, an acoustic emission(AE) system was used to record the AE signals generated by the diamond cutter penetration and the cuttings were collected for grain size analysis. The instrumented drilling system recorded the dynamic motions of the bit-rock interface using a laser displacement sensor, a load cell, and an LVDT(linear variable differential transformer) recorded the dynamic WOB and the ROP, respectively. Calibration with the drilling system showed that rotary speed was approximately the same at any given WOB, facilitating comparison of the results at the same WOB. Analysis of the experimental results shows that the ROP of the bit at any given WOB increased with higher amplitude of axial bit-rock vibration, and the drill cuttings increased in size with a higher ROP. Spectral analysis of the AEs indicated that the higher ROP and larger cutting size were correlated with a higher AE energy and a lower AE frequency. This indicated that larger fractures were being created to generate larger cutting size. Overall, these results indicate that a greater magnitude of axial bit-rock vibration produces larger fractures and generates larger cuttings which, at the same rotary speed, results in a higher ROP. 展开更多
关键词 Active bit vibration Diamond coring drilling Drill-off tests(DOTs) Acoustic emission(AE) Drilling performance Penetration mechanism Cutting size analysis
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Experimental and MD simulation of 3-dodecyloxypropanamine and 3-tetradecyloxypropylamine adsorbed onto quartz(101) surface 被引量:3
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作者 Zhouyueyang Cheng Yimin Zhu +1 位作者 Yanjun Li Stephen Butt 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2021年第6期1033-1042,共10页
In this paper,two surfactants,3-dodecyloxypropanamine(DOPA) and 3-tetradecyloxypropylamine(TOPA),were synthesized and used as collectors in the quartz micro-flotation in the laboratory.Microflotation tests,FT-IR,XPS m... In this paper,two surfactants,3-dodecyloxypropanamine(DOPA) and 3-tetradecyloxypropylamine(TOPA),were synthesized and used as collectors in the quartz micro-flotation in the laboratory.Microflotation tests,FT-IR,XPS measurements,and ab initio Molecular Dynamics(MD) simulations were conducted to research DOPA,TOPA,and dodecylamine(DDA)'s adsorption mechanisms onto quartz(101)surfaces.The results of micro-flotation show that the adsorption of DOPA and TOPA onto quartz surface is more robust than that of DDA.The zeta-potential result shows that the DOPA/TOPA was adsorbed on quartz through electrostatic attraction.Then,MD simulation adsorption models were built to compare the computational properties of the three surfactants,such as the radial distribution function,and the interaction energies between the collectors and the quartz cleavage surface.The interaction energies of surfactants(RNH_(3)^(+) or RNH_(2)) on the quartz surface explained why the pH range of DOPA/TOPA is wider than that of DDA.XPS analyses and MD simulations confirmed that DOPA bonded with the(101) surface of quartz through three types of hydrogen bonds between the-NH_(2) of DOPA and the O atom of quartz.The hydrogen bonds of type A and type C were the most likely type and more potent than those of type B. 展开更多
关键词 Quartz(101)surface Flotation Molecular dynamics 3-Dodecyloxypropanamine Adsorption
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Development and Modeling of Remotely Operated Scaled Multi-wheeled Combat Vehicle Using System Identification 被引量:1
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作者 A.N.Ouda Amr Mohamed +2 位作者 Moustafa EI-Gindy Haoxiang Lang Jing Ren 《International Journal of Automation and computing》 EI CSCD 2019年第3期261-273,共13页
This paper describes the development and modeling of a remotely operated scaled multi-wheeled combat vehicle(ROMWCV)using system identification methodology for heading angle tracking.The vehicle was developed at the v... This paper describes the development and modeling of a remotely operated scaled multi-wheeled combat vehicle(ROMWCV)using system identification methodology for heading angle tracking.The vehicle was developed at the vehicle dynamics and crash research(VDCR)Lab at the University of Ontario Institute of Technology(UOIT)to analyze the characteristics of the full-size model.For such vehicles,the development of controllers is considered the most crucial issue.In this paper,the ROMWCV is developed first.An experimental test was carried out to record and analyze the vehicle input/output signals in open loop system,which is considered a multi-input-single-output(MISO)system.Subsequently,a fuzzy logic controller(FLC)was developed for heading angle tracking.The experiments showed that it was feasible to represent the dynamic characteristics of the vehicle using the system identification technique.The estimation and validation results demonstrated that the obtained identified model was able to explain 88.44%of the output variation.In addition,the developed FLC showed a good heading angle tracking. 展开更多
关键词 Autonomous multi-wheeled VEHICLE system IDENTIFICATION all wheel STEERING fuzzy logic(FL) parametric IDENTIFICATION
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Probability Density Analysis of Nonlinear Random Ship Rolling 被引量:1
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作者 CHEN Jia YANG Jianming +2 位作者 SHEN Kunfan CHANG Zongyu ZHENG Zhongqiang 《Journal of Ocean University of China》 SCIE CAS CSCD 2023年第5期1227-1242,共16页
Ship rolling in random waves is a complicated nonlinear motion that contributes substantially to ship instability and capsizing.The finite element method(FEM)is employed in this paper to solve the Fokker Planck(FP)equ... Ship rolling in random waves is a complicated nonlinear motion that contributes substantially to ship instability and capsizing.The finite element method(FEM)is employed in this paper to solve the Fokker Planck(FP)equations numerically for homoclinic and heteroclinic ship rolling under random waves described as periodic and Gaussian white noise excitations.The transient joint probability density functions(PDFs)and marginal PDFs of the rolling responses are also obtained.The effects of stimulation strength on ship rolling are further investigated from a probabilistic standpoint.The homoclinic ship rolling has two rolling states,the connection between the two peaks of the PDF is observed when the periodic excitation amplitude or the noise intensity is large,and the PDF is remarkably distributed in phase space.These phenomena increase the possibility of a random jump in ship motion states and the uncertainty of ship rolling,and the ship may lose stability due to unforeseeable facts or conditions.Meanwhile,only one rolling state is observed when the ship is in heteroclinic rolling.As the periodic excitation amplitude grows,the PDF concentration increases and drifts away from the beginning location,suggesting that the ship rolling substantially changes in a cycle and its stability is low.The PDF becomes increasingly uniform and covers a large region as the noise intensity increases,reducing the certainty of ship rolling and navigation safety.The current numerical solutions and analyses may be applied to evaluate the stability of a rolling ship in irregular waves and capsize mechanisms. 展开更多
关键词 ship rolling homoclinic rolling heteroclinic rolling finite element method Fokker Planck equation probability density function
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Spatial Estimation of Rainfall Distribution and Its Classification in Duhok Governorate Using GIS 被引量:1
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作者 Mohamad J. Noori Hussein H. Hassan Yaseen T. Mustafa 《Journal of Water Resource and Protection》 2014年第2期75-82,共8页
Rainfall is a significant portion of hydrologic data. Rainfall records, however, are often incomplete due to several factors. In this study, the inverse distance weighting (IDW) method integrated with GIS is used to e... Rainfall is a significant portion of hydrologic data. Rainfall records, however, are often incomplete due to several factors. In this study, the inverse distance weighting (IDW) method integrated with GIS is used to estimate the rainfall distribution in Duhok Governorate. A total of 25 rain fall stations and rainfall data between 2000 and 2010 were used, where 6 rainfall stations were used for cross-validation. In addition, the relationship between interpolation accuracy and two critical parameters of IDW (Power α value, and a radius of influence) was evaluated. Also, the rainfall distribution of Duhok Governorate was classified. As an output of this study and in most cases, the optimal parameters for IDW in interpolating rainfall data must have a radius of influence up to (15 - 60 km). However, the optimal α values varied between 1 and 5. Based on the results of this study, we concluded that the IDW is an appropriate method of spatial interpolation to predict the probable rainfall data in Duhok Governorate using α = 1 and search radius = 105 km for all the 25 rainfall stations. 展开更多
关键词 GEOGRAPHIC Information Systems (GIS) INVERSE Distance Weighting (IDW) SPATIAL INTERPOLATION RAINFALL Data
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Fundamental Limits of Doppler Shift-Based, ToA-Based,and TDoA-Based Underwater Localization 被引量:1
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作者 Zijun Gong Cheng Li Ruoyu Su 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2023年第7期1637-1639,共3页
Dear Editor,This paper is concerned with the underwater localization based on acoustic signals. Specifically, we will focus on the search of an underwater target that can constantly broadcast a beacon signal, such as ... Dear Editor,This paper is concerned with the underwater localization based on acoustic signals. Specifically, we will focus on the search of an underwater target that can constantly broadcast a beacon signal, such as a black box. Common measurements for localization are Doppler shift [1], time of arrival(ToA) [2]–[4], time difference of arrival(TDoA) [5], [6], angle of arrival(AoA) [7], etc. 展开更多
关键词 TDOA TOA underwater
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Application of Radial Basis Function Learning Algorithm in Petroleum Engineering: Bottom-Hole Pressure Prediction 被引量:1
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作者 Mehdi Mohammadpoor Farshid Torabi 《材料科学与工程(中英文A版)》 2011年第4X期586-591,共6页
关键词 径向基函数神经网络 压力预测 石油工程 井底压力 学习算法 垂直多相流 RBFNN 应用
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Studying the Effect of Different Gas-Phase Chemical Kinetic Mechanisms on the Formation of Oxidants, Nitrogen Compounds and Ozone in Arid Regions 被引量:1
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作者 Mohammed Mujtaba Shareef Tahir Husain Badr Alharbi 《Journal of Environmental Protection》 2019年第8期1006-1031,共26页
CMAQ was implemented in the central region of Saudi Arabia and the effect of simulating models using various chemical mechanisms on selected oxidants, nitrogen species, and O3 was investigated. CB05TUCL predicted OH, ... CMAQ was implemented in the central region of Saudi Arabia and the effect of simulating models using various chemical mechanisms on selected oxidants, nitrogen species, and O3 was investigated. CB05TUCL predicted OH, MEPX, and NOz about 7%, 7.7%, and 8% more than CB05E51 respectively;however, there was no observable difference in the O3 predictions. The differences in variations of SAPRC07 mechanism (SAPRC07TB, SAPRC07TC, and SAPRC07TIC) for all parameters were less than 1%. RACM2 produced the highest OH and H2O2 concentrations. RACM2 enhanced OH production in the range of 24% - 32% and H2O2 by 9% over other mechanisms;these are comparatively less than the findings of other studies. Similarly, CB05 produced over 40% more PAN concentration than CB05. Moreover, PAN concentrations produced by all mechanisms were very high compared to other studies. SAPRC07 produced approximately 3% more mean surface O3 concentration than RACM2 and approximately 10% more than CB05. RACM2 O3 predictions were higher than CB05 by 7%. The predicted O3 concentrations by CB05, RACM2, and SAPRC07 were 6%, 11%, and 15% more than the average observed concentrations, which indicate that closest predictions to the observed values were by CB05. This study concludes that there is a wide variation of mechanisms with respect to the predictions of oxidants and nitrogen compounds;however, less variation is noticed in predictions of O3. For any air pollution control strategies and photochemical modeling studies in the current region or in any other arid regions, the CB05 mechanism is recommended. 展开更多
关键词 Air Quality Modeling PHOTOCHEMICAL Mechanisms OZONE RIYADH Arid CMAQ
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Simulating Coupled Longitudinal, Pitch and Bounce Dynamics of Trucks with Flexible Frames 被引量:1
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作者 D. Geoff Rideout 《Modern Mechanical Engineering》 2012年第4期176-189,共14页
Simulating the dynamic response of trucks requires that a model be constructed and subjected to road inputs. Inclusion or omission of flexible frame effects is often based on intuition or assumption. If frame vibratio... Simulating the dynamic response of trucks requires that a model be constructed and subjected to road inputs. Inclusion or omission of flexible frame effects is often based on intuition or assumption. If frame vibration is assumed to be significant, it is typically incorporated in one of two ways. Either a complex finite element model of the frame is used, or a simplified linear modal expansion model (which assumes small motions) is employed. The typical low-order modal expansion model, while computationally efficient and easier to use, is limited by the fact that 1) large rigid body motions and road grade changes are not supported, and 2) longitudinal dynamics are not coupled to vertical and bounce dynamics. In this paper, a bond graph model is presented which includes coupled pitch and bounce motions, longitudinal dynamics, and transverse frame vibration. Large rigid body motions are allowed, onto which small flexible vibrations are superimposed. Frame flexibility is incorporated using modal expansion of a free-free beam. The model allows for a complete pitch-plane representation in which motive forces can propel the truck forward over varying terrain, including hills. The effect of frame flexibility on vehicle dynamics can then be studied. This is an extension of the typical half-car model in which suspension motion is assumed vertical, pitch angles are small, and longitudinal dynamics are completely decoupled or omitted. Model output shows the effect of frame flexibility on vehicle responses such as forward velocity, pitch angle, and payload acceleration. Participation of individual modes can be seen to increase as road input approaches their natural frequency. The bond graph formalism allows for any or all flexible frame modes to be easily removed from the model if their effects are negligible, and for inclusion of more complex submodels for components such as suspension and engine if desired. 展开更多
关键词 TRUCK Model Vehicle DYNAMICS PITCH Plane Frame FLEXIBILITY BOND Graphs
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Control System Development and Test for the Operation of a Micro-Grid System—PART I 被引量:1
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作者 Razzaqul Ahshan Mohammad Tariq Iqbal +1 位作者 eorge K. I. Mann John E. Quaicoe 《Smart Grid and Renewable Energy》 2014年第12期291-301,共11页
This paper presents design, analysis and simulation performance of an active power controller for stable and reliable operation of a micro-grid system. Power balance between generation and consumer is a critical issue... This paper presents design, analysis and simulation performance of an active power controller for stable and reliable operation of a micro-grid system. Power balance between generation and consumer is a critical issue for stable and reliable operation of the micro-grid systems. This issue becomes more critical when a micro-grid system contains stochastic nature distributed generations such as wind and solar because their output power changes non-uniformly. In order to achieve accurate and fast power balance in such a micro-grid system, power in the system has to be regulated continuously. Such an objective can be achieved using droop based alternating current control technique. Because the droop characteristic employed into the developed controller initiates determining the power deviation in the system which is continuously regulated by controlling the current flow into dump power resistors. The designed controller is simulated for the operation of a micro-grid system in stand-alone mode under various operating conditions. The simulated results show the ability of the developed controller for stable and reliable operation of the micro-grid that contains renewable sources. The experimental development of the micro-grid system and the testing of the developed active power controller are presented in PART II of this paper. 展开更多
关键词 Power BALANCE FREQUENCY Control RENEWABLE Energy SOURCES MICRO-GRID
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Optimised Design and Analysis of Solar Water Pumping Systems for Pakistani Conditions
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作者 Usman Ashraf M. Tariq Iqbal 《Energy and Power Engineering》 2020年第10期521-542,共22页
This paper is about the optimized design and analysis of two solar water pumping systems in which one of the systems is designed with a battery bank and other with a cylindrical water tank for a selected site in Pakis... This paper is about the optimized design and analysis of two solar water pumping systems in which one of the systems is designed with a battery bank and other with a cylindrical water tank for a selected site in Pakistan. The design, sizing, cost analysis and steady state analysis of the proposed systems were done in HOMER and dynamic analysis of the designed system with battery bank was performed in MATLAB/Simulink. The simulations performed in HOMER involved proper mapping of the loads which helped to evaluate the PV panel requirement, inverter rating, batteries (in case of battery based solution), modeling of water tank as a deferrable load (in case of solution based of water tank) and detailed cost analysis for a life time of 25 years. To verify the design of the solar water pumping system with battery bank, a simulation in MATLAB/Simulink for study of dynamic behavior of the overall system was performed which involved mathematical modeling of a PV panel, buckboost converter, inverter, battery bank and motor/pump, a perturb and observe maximum power point tracking algorithm based control system. Analysis was conducted based on the economic results that indicate designed solar water pumping system with water tank would be a cheaper solution as compared to solar water pumping system with a battery bank. This work can be taken as a case study for the understanding and optimized designs of solar water pumping system with battery bank and with cylindrical tank in Pakistani conditions. 展开更多
关键词 Solar Water Pumping System MATLAB Simulink Solar Energy HOMER Manual Formulation Methods Computers Based Method Steady State Modeling Dynamic Modeling Solar Panels
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Hybrid artificial neural networks and analytical model for prediction of optical constants and bandgap energy of 3D nanonetwork silicon structures
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作者 Shreeniket Joshi Amirkianoosh Kiani 《Opto-Electronic Advances》 SCIE 2021年第10期11-23,共13页
The aim of this study is to develop a reliable method to determine optical constants for 3D-nanonetwork Si thin films manufactured using a pulsed-laser ablation technique that can be applied to other materials synthes... The aim of this study is to develop a reliable method to determine optical constants for 3D-nanonetwork Si thin films manufactured using a pulsed-laser ablation technique that can be applied to other materials synthesized by this tech-nique.An analytical method was introduced to calculate optical constants from reflectance and transmittance spectra.Optical band gaps for this novel material and other important insights on the physical properties were derived from the optical constants.The existing optimization methods described in the literature were found to be complex and prone to errors while determining optical constants of opaque materials where only reflectance data is available.A supervised Deep Learning Algorithm was developed to accurately predict optical constants from the reflectance spectrum alone.The hybrid method introduced in this study was proved to be effective with an accuracy of 95%. 展开更多
关键词 3D nanonetwork NANOSTRUCTURES optical properties artificial neural network.
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Utilization of CO2 Injection to Improve Oil Recovery of the Handsworth Bakken Formation
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作者 Farshid Torabi Jamie Lee French Tyler Scharnatta Mehdi Mohammadpoor Ryan Richard Wilton 《Journal of Earth Science and Engineering》 2012年第6期366-375,共10页
The Bakken formation has become a prominent oil resource for south-east Saskatchewan, especially with the advent of horizontal well technology and new hydraulic fracturing methods. As more wells are drilled, there is ... The Bakken formation has become a prominent oil resource for south-east Saskatchewan, especially with the advent of horizontal well technology and new hydraulic fracturing methods. As more wells are drilled, there is a desire to determine whether there is potential for improved oil recovery and to evaluate the economic feasibility. This paper evaluates the benefit of implementing waterflooding, CO2 injection or WAG (water-alternating-gas) recovery methods for improved oil recovery of the Bakken formation. A simulation model resembling the study area was built using CMG-GEM (computer modeling group-generalized equation of state model) reservoir simulation package and a history match of the primary recovery data available was performed. Based on the simulation results, it was concluded that waterflooding had a significant influence on the oil recovery factor, although COz provided the highest increase in crude oil recovery, The capital expenditure for surface facilities and cost of injected fluid was the most economically viable for implementation of waterflooding. The WAG injection simulation results were similar to CO2 injection, except that reservoir pressure was able to be better maintained. Given that high-quality source water is available, waterflooding is the most economically feasible choice according to the simulation results obtained from this study. 展开更多
关键词 Improved oil recovery WATERFLOODING CO2 injection WAG injection CMG.
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Assessment of Microbial Communities and Their Relationship with Enzymatic Activity during Composting
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作者 Khoshrooz Kazemi Baiyu Zhang Leonard M. Lye 《World Journal of Engineering and Technology》 2017年第3期93-102,共10页
Microbial communities and enzyme activities are the main players during municipal solid waste (MSW) composting, but the relationship between microbial communities (i.e., mesophilic and thermophilic ones) and enzyme ac... Microbial communities and enzyme activities are the main players during municipal solid waste (MSW) composting, but the relationship between microbial communities (i.e., mesophilic and thermophilic ones) and enzyme activities (i.e., dehydrogenase, β-glucosidase, phosphatase and urea) has not been well studied. Therefore, the objective of this work is to determine the enzymes profiles during municipal solid waste (MSW) composting and study the relationship between the mesophilic and thermophilic microbial profiles and enzyme activities. MSW was composted in a bench-scale composting reactor. Parameters including temperature, oxygen uptake rate, numbers of microbial populations (mesophilic and thermophilic bacteria and fungi) and enzyme activities were measured. Results showed higher dehydrogenase activities are related to higher numbers of mesophilic bacteria, while higher phosphatase and urea activities are associated with higher numbers of thermophilic fungi and mesophilic bacteria at the later stage of composting. In addition, results of the correlation analysis indicated significant correlations among enzyme activities and microbial population. 展开更多
关键词 COMPOSTING MICROBIAL POPULATION ENZYME Activity CORRELATION Analysis
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Design and Implementation of a Wireless Networked Water Level Control System
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作者 Lixuan Lu Ross Lewis +1 位作者 Ming Hu Ryan Lin 《Journal of Computer and Communications》 2015年第5期159-163,共5页
The design of a wireless water level control system is introduced and discussed in detail. In this system, the wireless Proportional Integral (PI) controller is developed using the LabVIEW graphical user programming l... The design of a wireless water level control system is introduced and discussed in detail. In this system, the wireless Proportional Integral (PI) controller is developed using the LabVIEW graphical user programming language. Zigbee wireless technology is chosen for the wireless data transfer system. The experimental testbed was built and the system software and hardware were implemented. In order to compare the performance of the wired and wireless system, a corresponding wired water level control system was built. Experimental results show that under the same PI parameters, the settling time of the wired system is 3.3 times faster than the wireless system. However, the percent overshoot using the wireless controller is 4% smaller. 展开更多
关键词 WIRELESS NETWORKED Control System Zigbee WIRELESS PROTOCOL Labview GRAPHICAL PROGRAMMING
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