Harvesting the mechanical energy dissipated by vehicles passing over road to power micro-electromechanical systems(MEMS)in intelligent transportation systems(ITS)is an important way to realize self-powered traffic con...Harvesting the mechanical energy dissipated by vehicles passing over road to power micro-electromechanical systems(MEMS)in intelligent transportation systems(ITS)is an important way to realize self-powered traffic condition monitoring.However,the limitations of traditional vehicle energy harvesting speed bumps such as single functionality and heavy-shock on vehicles are not conducive to developing energy harvesting speed bumps for multi-functionalization,versatility and intelligence.In this work,a compact hybridized triboelectricelectromagnetic road energy harvester(CHREH)device is designed.The vehicle's wheels impact force drives the sliding plate movement and triggers the triboelectric generator(TENG)unit and electromagnetic generator(EMG)unit to produce electricity.The enhanced TENG built by multi-layer folded structure is assembled using rGO and surface-patterning modified polydimethylsiloxane(PDMS)compositefilm.Furthermore,the mechanism and electrical output performance of EMG and TENG are theoretically simulated and experimentally tested.Particularly,TENG unit achieved a peak power of 7.21 mW and the EMG unit reached a peak power of 0.74 mW at an excitation frequency of 5 Hz,in addition to the superior durability.Further,the demonstration of application of self-powered car warning and speed monitoring were conducted.The CHREH offers a feasible approach for selfpowered applications deployable to the low power consumption electronic devices and ITS.展开更多
Nowadays,huge consumption of fossil fuels brings about serious energy crisis and environmental problems,which urge researchers to explore novel sustainable energy sources and storage systems[1,2].
The allelic frequency, the polymorphic information contents （PIC）, the number of effective alleles, the heterozygosity, and the genetic distances were studied in three imported meat sheep （Suffolk, Dorset, Texel） ...The allelic frequency, the polymorphic information contents （PIC）, the number of effective alleles, the heterozygosity, and the genetic distances were studied in three imported meat sheep （Suffolk, Dorset, Texel） and their F1 crossbred obtained from those crossed with indigenous Small Tail Hun Sheep （Suffolk♂× Small Tail Hun Sheep, SH; Dorset ♂× Small Tail Han Sheep♂, DH; Texel♂× Small Tail Hart Sheep ♀, TH） using six microsatellite DNA loci. The perpormences of three-breed crossbred （Suffolk ♂× DH ♀, Suffolk ♂× TH ♀, Texel ♂× SH ♀, Texel ♂× DH ♀, Dorset ♂× TH ♀, and Dorset ♂× SH ♀ ） were tested. The results indicated that there were genetic polymorphisms at six microsatellite loci in six sheep populations. Six microsatellite loci could be used for genetic diversity evaluation in sheep populations. The order of three-breed heterosis by the analysis of genetic relationship from large to small was Texel ♂× DH ♀, Suffolk ♂× DH ♀, Suffolki ♂× TH ♀, Texel ♂× SH ♀, Dorset ♂×TH ♀, and Dorset ♂× SH ♀, which was in accordance with the testing results on actual heterosis. These results showed that prediction of the best three-breed hybridized combination among sheep breeds by microsatellite DNA polymorphism was feasible, which will have an important value on the reasonable utilization of introduced meat sheep and sheep breeding in our country in the future.展开更多
This paper proposes a Hybridized Ant Colony Optimization (HACO) algorithm. It integrates the advantages of Ant System (AS) and Ant Colony System (ACS) of solving optimization problems. The main focus and core of the H...This paper proposes a Hybridized Ant Colony Optimization (HACO) algorithm. It integrates the advantages of Ant System (AS) and Ant Colony System (ACS) of solving optimization problems. The main focus and core of the HACO algorithm are based on annexing the strengths of the AS, ACO and the Max-Min Ant System (MMAS) previously proposed by various researchers at one time or the order. In this paper, the HACO algorithm for solving optimization problems employs new Transition Probability relations with a Jump transition probability relation which indicates the point or path at which the desired optimum value has been met. Also, it brings to play a new pheromone updating rule and introduces the pheromone evaporation residue that calculates the amount of pheromone left after updating which serves as a guide to the successive ant traversing the path and diverse local search approaches. Regarding the computational efficiency of the HACO algorithm, we observe that the HACO algorithm can find very good solutions in a short time, as the algorithm has been tested on a number of combinatorial optimization problems and results shown to compare favourably with analytical results. This strength can be combined with other metaheuristic approaches in the future work to solve complex combinatorial optimization problems.展开更多
A scheme of investigating the intracellular metabolic fluxes in central metabolism of Saccharomyces cerevisiae based on isotope model and tracer experiment was developed. The metabolic model applied in this study incl...A scheme of investigating the intracellular metabolic fluxes in central metabolism of Saccharomyces cerevisiae based on isotope model and tracer experiment was developed. The metabolic model applied in this study includes the Embden-Meyerhof-Parnas pathway,the pentose phosphate pathway,the tricarboxylic acid cycle,CO2 anaplerotic reactions,ethanol and acetate formation,and pathways involved in amino acid synthesis. The approach of hybridized genetic algorithm combined with the sequential simplex technique was used to optimize a quadratic error function without the requirement of the information on the partial derivatives. The impact of some key pa-rameters on the algorithm was studied. This approach was proved to be rapid and numerically stable in the analysis of the central metabolism of S.cerevisiae.展开更多
The purpose of this paper is to develop a hybridized discontinuous Galerkin(HDG)method for solving the Ito-type coupled KdV system.In fact,we use the HDG method for discre-tizing the space variable and the backward Eu...The purpose of this paper is to develop a hybridized discontinuous Galerkin(HDG)method for solving the Ito-type coupled KdV system.In fact,we use the HDG method for discre-tizing the space variable and the backward Euler explicit method for the time variable.To linearize the system,the time-lagging approach is also applied.The numerical stability of the method in the sense of the L2 norm is proved using the energy method under certain assumptions on the stabilization parameters for periodic or homogeneous Dirichlet bound-ary conditions.Numerical experiments confirm that the HDG method is capable of solving the system efficiently.It is observed that the best possible rate of convergence is achieved by the HDG method.Also,it is being illustrated numerically that the corresponding con-servation laws are satisfied for the approximate solutions of the Ito-type coupled KdV sys-tem.Thanks to the numerical experiments,it is verified that the HDG method could be more efficient than the LDG method for solving some Ito-type coupled KdV systems by comparing the corresponding computational costs and orders of convergence.展开更多
Pursuit of energy-harvesting or-storage materials to realize outstanding electricity output from nature has been regarded as a promising strategy to resolve the energy-lack issue in the future. Among them,the solar ce...Pursuit of energy-harvesting or-storage materials to realize outstanding electricity output from nature has been regarded as a promising strategy to resolve the energy-lack issue in the future. Among them,the solar cell as a solar-to-electrical conversion device has been attracted enormous interest to improve the efficiency. However, the ability to generate electricity is highly dependent on the weather conditions,in other words, there is nearly zero power output in dark-light conditions, such as rainy, cloudy, and night, lowering the monolithic power generation capacity. Here, we present a bifunctional polyaniline film via chemical bath deposition, which can harvest energy from the rain, yielding an induced current of 2.57 μA and voltage of 65.5 μV under the stimulus of real raindrop. When incorporating the functional PANi film into the traditional dye sensitized solar cell as a counter electrode, the hybridized photovoltaic can experimentally realize the enhanced output power via harvesting energy from rainy and sunny days. The current work may show a new path for development of advanced solar cells in the future.展开更多
Partially replacing polyvinyl-alcohol(PVA)fibers with polypropylene(PP)fibers in strain-hardening cementitious composites(fiber hybridization)modify certain mechanical properties of these materials.The hybridization b...Partially replacing polyvinyl-alcohol(PVA)fibers with polypropylene(PP)fibers in strain-hardening cementitious composites(fiber hybridization)modify certain mechanical properties of these materials.The hybridization based on the introduction of low-modulus hydrophobic polypropylene fibers improves the ductility and the strain-hardening behavior of the cementitious composites containing polyvinyl-alcohol fibers of different types(PVA-SHCC).Pull-out tests indicate that adding PP fibers increases the energy capacity of the hybrid composite with respect to the material containing only PVA fibers under tensile loading,and PP-fiber geometry(i.e.,section shape and length)is a key factor in enhancing the strain capacity.展开更多
The chemical bonding nature of rare earth（RE） elements can be studied by a quantitative analysis of electron domain of an atom. The outer electrons of RE elements are within the valence shell 4f^（0-14）5d^（0-1）6s...The chemical bonding nature of rare earth（RE） elements can be studied by a quantitative analysis of electron domain of an atom. The outer electrons of RE elements are within the valence shell 4f^（0-14）5d^（0-1）6s^2, which are involved in all chemical bonding features. We in this work found that the chemical bonding characteristics of 4f electrons are a kind of hybridizations, and classified them into three types of chemical bonding of 4f^（0-14）5d^（0-1）6s^2, furthermore, the coordination number ranging from 2 to 16 could thus be determined. We selected Y（NO_3）_3, La（NO_3）_3, Ce（NO_3）_3, YCl_3, LaCl_3, and CeCl_3 as examples to in-situ observe their IR spectra of chemical bonding behaviors of Y^（3＋）, La^（3＋） and Ce^（3＋） cations, which could show different chemical bonding modes of 4f and 5d electrons. In the present study, we obtained the direct criterion to confirm whether 4f electrons can participate in chemical bonding, that is, only when the coordination number of RE cations is larger than 9.展开更多
This paper proposes the use of the flexible tolerance method(FTM) modified with scaling of variables and hybridized with different unconstrained optimization methods to solve real constrained optimization problems.The...This paper proposes the use of the flexible tolerance method(FTM) modified with scaling of variables and hybridized with different unconstrained optimization methods to solve real constrained optimization problems.The benchmark problems used to analyze the performance of the methods were taken from G-Suite functions.The original method(FTM) and other four proposed methods:(i) FTM with scaling of variables(FTMS),(ii) FTMS hybridized with BFGS(FTMS-BFGS),(iii) FTMS hybridized with modified Powell's method(FTMS-Powell)and(iv) FTMS hybridized with PSO(FTMS-PSO), were implemented. The success rates of the methods were 80%,100%, 75%, 95% and 85%, for FTM, FTMS, FTMS-BFGS, FTMS-Powell and FTMS-PSO, respectively. Numerical experiments including real constrained problems indicated that FTMS gave the best performance, followed by FTMSPowell and FTMS-PSO. Despite the inferior performance compared to FTMS and FTMS-Powell, the FTMS-PSO method presented some advantages since good different initial points could be obtained, which allow exploring different routes through the solution space and to escape from local optima. The proposed methods proved to be an effective way of improving the performance of the original FTM.展开更多
The energy harvesting technology for the ubiquitous natural wind enables a desirable solution to the issue of distributed sensors in the bridge environmental sensing Internet of Things(Io T)system being restricted to ...The energy harvesting technology for the ubiquitous natural wind enables a desirable solution to the issue of distributed sensors in the bridge environmental sensing Internet of Things(Io T)system being restricted to conventional energy supply.In this work,a self-powered system based on a compact galloping piezoelectric-triboelectric energy harvester(GPTEH)is developed to achieve efficient wind energy harvesting.The GPTEH is constructed on the prototype of a cantilever structure with piezoelectric macro-fiber composite(MFC)sheets and a rectangular bluff body with triboelectric nanogenerators(TENGs).Through a special swing-type structural design with iron blocks inside the bluff body,the GPTEH exhibits preferable aerodynamic behavior and excellent energy conversion efficiency,compared to conventional cantilever kind of piezoelectric wind energy harvester(PWEH).The GPTEH also demonstrates the capability of high output power density(PEH of 23.65 W m^(-2)and TENG of 1.59 W m^(-2)),superior response wind speed(about 0.5 m s^(-1)),and excellent long-term stability(over 14000 cyclic tests).Furthermore,a power management system is developed to efficiently utilize the output energy from GPTEH to power the sensors and wirelessly transmit environmental data to the terminals.The proposed GPTEH-powered system exhibits a great potential for the bridge environmental monitoring and Io T technologies.展开更多
Machine learning models can predict material properties quickly and accurately at a low computational cost.This study generated novel hybridized nanocomposites with unsaturated polyester resin as the matrix and Areca ...Machine learning models can predict material properties quickly and accurately at a low computational cost.This study generated novel hybridized nanocomposites with unsaturated polyester resin as the matrix and Areca fruit husk fiber(AFHF),tamarind fruit fiber(TFF),and nano-sized coconut shell powder(NCSP).It is challenging to determine the optimal proportion of raw materials in this composite to achieve maximum mechanical properties.This task was accomplished with the help of ML techniques in this study.The tensile strength of the hybridized nanocomposite was increased by 134.06% compared to the neat unsaturated polyester resin at a 10:5:2 wt.% ratio,AFHF:TFF:NCSP.The stiffness and impact behavior of hybridized nanocomposites were similar.The scanning electron microscope showed homogeneous reinforcement and nanofiller distribution in the matrix.However,the hybridized nanocomposite with a 20:5:0 wt.% combination ratio had the highest strain at break of 5.98%,AFHF:TFF:NCSP.The effectiveness of recurrent neural networks and recurrent neural networks with Levenberg’s algorithm was assessed using R2,mean absolute errors,and minimum squared errors.Tensile and impact strength of hybridized nanocomposites were well predicted by the recurrent neural network with Levenberg’s model with 2 and 3 hidden layers,80 neurons and 80 neurons,respectively.A recurrent neural network model with 4 hidden layers,60 neurons,and 2 hidden layers,100 neurons predicted hybridized nanocomposites’Young’s modulus and elongation at break with maximum R2 values.The mean absolute errors and minimum squared errors were evaluated to ensure the reliability of the machine learning algorithms.The models optimize hybridized nanocomposites’mechanical properties,saving time and money during experimental characterization.展开更多
为探究混合Ⅲ(HybridⅢ)假人与人体乘员约束测试装置(test device for human occupant restraint,THOR)在小偏置碰撞试验中的生物逼真度差异,对比分析了HybridⅢ假人、THOR和人体安全模型(total human model for safety,THUMS)3种乘员...为探究混合Ⅲ(HybridⅢ)假人与人体乘员约束测试装置(test device for human occupant restraint,THOR)在小偏置碰撞试验中的生物逼真度差异,对比分析了HybridⅢ假人、THOR和人体安全模型(total human model for safety,THUMS)3种乘员模型在不同小偏置碰撞模式下的碰撞响应情况.采用有限元数值模拟方法,以吸能与侧滑两种典型小偏置碰撞模式的整车模型在碰撞过程中的脉冲曲线作为边界条件;结合包含完整内饰结构的某中型轿车驾驶舱模型和HybridⅢ假人、THOR以及THUMS,构建驾驶员侧约束系统仿真模型,分析小偏置碰撞过程中乘员模型的运动学响应与损伤风险差异.与HybridⅢ假人相比,THOR躯干的整体运动趋势与THUMS近似.在损伤方面,THOR头部、脑部和下肢部位的损伤风险与THUMS更接近.THOR胸部整体压缩量要高于HybridⅢ假人和THUMS 10 mm左右;颈部损伤风险大体介于HybridⅢ假人和THUMS中间,更接近THUMS.结果表明,THOR在小偏置碰撞过程中表现出的运动趋势与预测损伤风险的能力与THUMS更接近,与HybridⅢ假人相比,在小偏置碰撞过程中展现出了更高的生物逼真度.展开更多
Supercapacitors are gaining popularity due to their high cycling stability,power density,and fast charge and discharge rates.Researchers are ex-ploring electrode materials,electrolytes,and separat-ors for cost-effecti...Supercapacitors are gaining popularity due to their high cycling stability,power density,and fast charge and discharge rates.Researchers are ex-ploring electrode materials,electrolytes,and separat-ors for cost-effective energy storage systems.Ad-vances in materials science have led to the develop-ment of hybrid nanomaterials,such as combining fil-amentous carbon forms with inorganic nanoparticles,to create new charge and energy transfer processes.Notable materials for electrochemical energy-stor-age applications include MXenes,2D transition met-al carbides,and nitrides,carbon black,carbon aerogels,activated carbon,carbon nanotubes,conducting polymers,carbon fibers,and nanofibers,and graphene,because of their thermal,electrical,and mechanical properties.Carbon materials mixed with conducting polymers,ceramics,metal oxides,transition metal oxides,metal hydroxides,transition metal sulfides,trans-ition metal dichalcogenide,metal sulfides,carbides,nitrides,and biomass materials have received widespread attention due to their remarkable performance,eco-friendliness,cost-effectiveness,and renewability.This article explores the development of carbon-based hybrid materials for future supercapacitors,including electric double-layer capacitors,pseudocapacitors,and hy-brid supercapacitors.It investigates the difficulties that influence structural design,manufacturing(electrospinning,hydro-thermal/solvothermal,template-assisted synthesis,electrodeposition,electrospray,3D printing)techniques and the latest car-bon-based hybrid materials research offer practical solutions for producing high-performance,next-generation supercapacitors.展开更多
In this paper a hybridized weak Galerkin(HWG) finite element method for solving the Stokes equations in the primary velocity-pressure formulation is introduced.The WG method uses weak functions and their weak derivati...In this paper a hybridized weak Galerkin(HWG) finite element method for solving the Stokes equations in the primary velocity-pressure formulation is introduced.The WG method uses weak functions and their weak derivatives which are defined as distributions.Weak functions and weak derivatives can be approximated by piecewise polynomials with various degrees.Different combination of polynomial spaces leads to different WG finite element methods,which makes WG methods highly flexible and efficient in practical computation.A Lagrange multiplier is introduced to provide a numerical approximation for certain derivatives of the exact solution.With this new feature,the HWG method can be used to deal with jumps of the functions and their flux easily.Optimal order error estimates are established for the corresponding HWG finite element approximations for both primal variables and the Lagrange multiplier.A Schur complement formulation of the HWG method is derived for implementation purpose.The validity of the theoretical results is demonstrated in numerical tests.展开更多
Present of wind power is sporadically and cannot be utilized as the only fundamental load of energy sources.This paper proposes a wind-solar hybrid energy storage system(HESS)to ensure a stable supply grid for a longe...Present of wind power is sporadically and cannot be utilized as the only fundamental load of energy sources.This paper proposes a wind-solar hybrid energy storage system(HESS)to ensure a stable supply grid for a longer period.A multi-objective genetic algorithm(MOGA)and state of charge(SOC)region division for the batteries are introduced to solve the objective function and configuration of the system capacity,respectively.MATLAB/Simulink was used for simulation test.The optimization results show that for a 0.5 MW wind power and 0.5 MW photovoltaic system,with a combination of a 300 Ah lithium battery,a 200 Ah lead-acid battery,and a water storage tank,the proposed strategy reduces the system construction cost by approximately 18,000 yuan.Additionally,the cycle count of the electrochemical energy storage systemincreases from4515 to 4660,while the depth of discharge decreases from 55.37%to 53.65%,achieving shallow charging and discharging,thereby extending battery life and reducing grid voltage fluctuations significantly.The proposed strategy is a guide for stabilizing the grid connection of wind and solar power generation,capability allocation,and energy management of energy conservation systems.展开更多
Utilizing a nanogenerator to scavenge mechanical energy from our living environment is an effective method to solve the power source issue of portable electronics. We report a linear-grating hybridized electromagnetic...Utilizing a nanogenerator to scavenge mechanical energy from our living environment is an effective method to solve the power source issue of portable electronics. We report a linear-grating hybridized electromagnetic-triboelectric nanogenerator for scavenging the mechanical energy generated from sliding motions to sustainably power certain portable electronics. The hybridized nano- generator consists of a slider and a stator in the structural design, and possesses a 66-segment triboelectric nanogenerator （TENG） and a 9-segment electromagnetic generator （EMG） in the functional design. At a sliding acceleration of 20 m/s2 the hybridized nanogenerator can deliver maximum powers of 102.8 mW for the TENG at a loading resistance of 0.4 Mr2 and 103.3 mW for the EMG at a loading resistance of 6 kf2. With an optimal hybridized combination of the TENG with a transformer and the EMG with a power management circuit, a 10 mF capacitor can be easily charged to 2.8 V in 20 s. A packaged hybridized nanogenerator with a light weight of 140 g and small dimensions of 12 cm× 4 cm× 1.6 cm excels in scavenging low-frequency sliding energy to sustainably power portable electronics.展开更多
基金supported by the National Natural Science Foundation of China(Grant Nos.12172127 and 12202262)the Key Project of Scientific Research Project of Hunan Provincial Department of Education(Grant Nos.22A0515 and 21A0463)the Hunan Provincial Innovation Foundation For Postgraduate(Grant No.CX20231286).
文摘Harvesting the mechanical energy dissipated by vehicles passing over road to power micro-electromechanical systems(MEMS)in intelligent transportation systems(ITS)is an important way to realize self-powered traffic condition monitoring.However,the limitations of traditional vehicle energy harvesting speed bumps such as single functionality and heavy-shock on vehicles are not conducive to developing energy harvesting speed bumps for multi-functionalization,versatility and intelligence.In this work,a compact hybridized triboelectricelectromagnetic road energy harvester(CHREH)device is designed.The vehicle's wheels impact force drives the sliding plate movement and triggers the triboelectric generator(TENG)unit and electromagnetic generator(EMG)unit to produce electricity.The enhanced TENG built by multi-layer folded structure is assembled using rGO and surface-patterning modified polydimethylsiloxane(PDMS)compositefilm.Furthermore,the mechanism and electrical output performance of EMG and TENG are theoretically simulated and experimentally tested.Particularly,TENG unit achieved a peak power of 7.21 mW and the EMG unit reached a peak power of 0.74 mW at an excitation frequency of 5 Hz,in addition to the superior durability.Further,the demonstration of application of self-powered car warning and speed monitoring were conducted.The CHREH offers a feasible approach for selfpowered applications deployable to the low power consumption electronic devices and ITS.
基金supported by the National Natural Science Foundation of China(21601089)Jiangsu Specially Appointed Professor Program。
文摘Nowadays,huge consumption of fossil fuels brings about serious energy crisis and environmental problems,which urge researchers to explore novel sustainable energy sources and storage systems[1,2].
基金supported by the Key Project of Ministry of Science and Technology of China(2008BADB2B04-9)the Key Project of Hebei Province,China(07220401D-2)
文摘The allelic frequency, the polymorphic information contents （PIC）, the number of effective alleles, the heterozygosity, and the genetic distances were studied in three imported meat sheep （Suffolk, Dorset, Texel） and their F1 crossbred obtained from those crossed with indigenous Small Tail Hun Sheep （Suffolk♂× Small Tail Hun Sheep, SH; Dorset ♂× Small Tail Han Sheep♂, DH; Texel♂× Small Tail Hart Sheep ♀, TH） using six microsatellite DNA loci. The perpormences of three-breed crossbred （Suffolk ♂× DH ♀, Suffolk ♂× TH ♀, Texel ♂× SH ♀, Texel ♂× DH ♀, Dorset ♂× TH ♀, and Dorset ♂× SH ♀ ） were tested. The results indicated that there were genetic polymorphisms at six microsatellite loci in six sheep populations. Six microsatellite loci could be used for genetic diversity evaluation in sheep populations. The order of three-breed heterosis by the analysis of genetic relationship from large to small was Texel ♂× DH ♀, Suffolk ♂× DH ♀, Suffolki ♂× TH ♀, Texel ♂× SH ♀, Dorset ♂×TH ♀, and Dorset ♂× SH ♀, which was in accordance with the testing results on actual heterosis. These results showed that prediction of the best three-breed hybridized combination among sheep breeds by microsatellite DNA polymorphism was feasible, which will have an important value on the reasonable utilization of introduced meat sheep and sheep breeding in our country in the future.
文摘This paper proposes a Hybridized Ant Colony Optimization (HACO) algorithm. It integrates the advantages of Ant System (AS) and Ant Colony System (ACS) of solving optimization problems. The main focus and core of the HACO algorithm are based on annexing the strengths of the AS, ACO and the Max-Min Ant System (MMAS) previously proposed by various researchers at one time or the order. In this paper, the HACO algorithm for solving optimization problems employs new Transition Probability relations with a Jump transition probability relation which indicates the point or path at which the desired optimum value has been met. Also, it brings to play a new pheromone updating rule and introduces the pheromone evaporation residue that calculates the amount of pheromone left after updating which serves as a guide to the successive ant traversing the path and diverse local search approaches. Regarding the computational efficiency of the HACO algorithm, we observe that the HACO algorithm can find very good solutions in a short time, as the algorithm has been tested on a number of combinatorial optimization problems and results shown to compare favourably with analytical results. This strength can be combined with other metaheuristic approaches in the future work to solve complex combinatorial optimization problems.
基金Supported by the National Natural Science Foundation of China (No.20276065)the Special Funds for Major State BasicResearch Program of China (973 Program, 2007CB707805).
文摘A scheme of investigating the intracellular metabolic fluxes in central metabolism of Saccharomyces cerevisiae based on isotope model and tracer experiment was developed. The metabolic model applied in this study includes the Embden-Meyerhof-Parnas pathway,the pentose phosphate pathway,the tricarboxylic acid cycle,CO2 anaplerotic reactions,ethanol and acetate formation,and pathways involved in amino acid synthesis. The approach of hybridized genetic algorithm combined with the sequential simplex technique was used to optimize a quadratic error function without the requirement of the information on the partial derivatives. The impact of some key pa-rameters on the algorithm was studied. This approach was proved to be rapid and numerically stable in the analysis of the central metabolism of S.cerevisiae.
文摘The purpose of this paper is to develop a hybridized discontinuous Galerkin(HDG)method for solving the Ito-type coupled KdV system.In fact,we use the HDG method for discre-tizing the space variable and the backward Euler explicit method for the time variable.To linearize the system,the time-lagging approach is also applied.The numerical stability of the method in the sense of the L2 norm is proved using the energy method under certain assumptions on the stabilization parameters for periodic or homogeneous Dirichlet bound-ary conditions.Numerical experiments confirm that the HDG method is capable of solving the system efficiently.It is observed that the best possible rate of convergence is achieved by the HDG method.Also,it is being illustrated numerically that the corresponding con-servation laws are satisfied for the approximate solutions of the Ito-type coupled KdV sys-tem.Thanks to the numerical experiments,it is verified that the HDG method could be more efficient than the LDG method for solving some Ito-type coupled KdV systems by comparing the corresponding computational costs and orders of convergence.
基金financial support from the National Natural Science Foundation of China (61774139, 21503202 and61604143)Shandong Provincial Natural Science Foundation (ZR2015EM024)the Fundamental Research Funds for the Central Universities (201564002, 201762018)
文摘Pursuit of energy-harvesting or-storage materials to realize outstanding electricity output from nature has been regarded as a promising strategy to resolve the energy-lack issue in the future. Among them,the solar cell as a solar-to-electrical conversion device has been attracted enormous interest to improve the efficiency. However, the ability to generate electricity is highly dependent on the weather conditions,in other words, there is nearly zero power output in dark-light conditions, such as rainy, cloudy, and night, lowering the monolithic power generation capacity. Here, we present a bifunctional polyaniline film via chemical bath deposition, which can harvest energy from the rain, yielding an induced current of 2.57 μA and voltage of 65.5 μV under the stimulus of real raindrop. When incorporating the functional PANi film into the traditional dye sensitized solar cell as a counter electrode, the hybridized photovoltaic can experimentally realize the enhanced output power via harvesting energy from rainy and sunny days. The current work may show a new path for development of advanced solar cells in the future.
文摘Partially replacing polyvinyl-alcohol(PVA)fibers with polypropylene(PP)fibers in strain-hardening cementitious composites(fiber hybridization)modify certain mechanical properties of these materials.The hybridization based on the introduction of low-modulus hydrophobic polypropylene fibers improves the ductility and the strain-hardening behavior of the cementitious composites containing polyvinyl-alcohol fibers of different types(PVA-SHCC).Pull-out tests indicate that adding PP fibers increases the energy capacity of the hybrid composite with respect to the material containing only PVA fibers under tensile loading,and PP-fiber geometry(i.e.,section shape and length)is a key factor in enhancing the strain capacity.
基金supported by the National Natural Science Foundation of China(51125009,91434118,21401185,21521092)Hundred Talents Program of Chinese Academy of SciencesJilin Province Science and Technology Development Project(20170101092JC,20160520006JH)
文摘The chemical bonding nature of rare earth（RE） elements can be studied by a quantitative analysis of electron domain of an atom. The outer electrons of RE elements are within the valence shell 4f^（0-14）5d^（0-1）6s^2, which are involved in all chemical bonding features. We in this work found that the chemical bonding characteristics of 4f electrons are a kind of hybridizations, and classified them into three types of chemical bonding of 4f^（0-14）5d^（0-1）6s^2, furthermore, the coordination number ranging from 2 to 16 could thus be determined. We selected Y（NO_3）_3, La（NO_3）_3, Ce（NO_3）_3, YCl_3, LaCl_3, and CeCl_3 as examples to in-situ observe their IR spectra of chemical bonding behaviors of Y^（3＋）, La^（3＋） and Ce^（3＋） cations, which could show different chemical bonding modes of 4f and 5d electrons. In the present study, we obtained the direct criterion to confirm whether 4f electrons can participate in chemical bonding, that is, only when the coordination number of RE cations is larger than 9.
基金CAPES(Coordenacao de Aperfeicoamento de Pessoal de Nível Superior)CNPq(Conselho Nacional de Desenvolvimento Científicoe Tecnológico,grant number 161464/2013-0)for the financial support
文摘This paper proposes the use of the flexible tolerance method(FTM) modified with scaling of variables and hybridized with different unconstrained optimization methods to solve real constrained optimization problems.The benchmark problems used to analyze the performance of the methods were taken from G-Suite functions.The original method(FTM) and other four proposed methods:(i) FTM with scaling of variables(FTMS),(ii) FTMS hybridized with BFGS(FTMS-BFGS),(iii) FTMS hybridized with modified Powell's method(FTMS-Powell)and(iv) FTMS hybridized with PSO(FTMS-PSO), were implemented. The success rates of the methods were 80%,100%, 75%, 95% and 85%, for FTM, FTMS, FTMS-BFGS, FTMS-Powell and FTMS-PSO, respectively. Numerical experiments including real constrained problems indicated that FTMS gave the best performance, followed by FTMSPowell and FTMS-PSO. Despite the inferior performance compared to FTMS and FTMS-Powell, the FTMS-PSO method presented some advantages since good different initial points could be obtained, which allow exploring different routes through the solution space and to escape from local optima. The proposed methods proved to be an effective way of improving the performance of the original FTM.
基金supported by the National Key R&D Program of China(Grant No.2020YFA0711700)the National Natural Science Foundation of China(Grant Nos.52122801,11925206,U22A20254,U23A20659,and51978609)+3 种基金Zhejiang Provincial Natural Science Foundation for Distinguished Young Scientists(Grant No.LR20E080003)the Key Research Project of Zhejiang(Grant No.LD22E030007)the“Leading Goose”R&D Program of Zhejiang Province(Grant No.2022C01136)Zhejiang University Education Foundation Global Partnership Fund(Grant No.100000-11320)。
文摘The energy harvesting technology for the ubiquitous natural wind enables a desirable solution to the issue of distributed sensors in the bridge environmental sensing Internet of Things(Io T)system being restricted to conventional energy supply.In this work,a self-powered system based on a compact galloping piezoelectric-triboelectric energy harvester(GPTEH)is developed to achieve efficient wind energy harvesting.The GPTEH is constructed on the prototype of a cantilever structure with piezoelectric macro-fiber composite(MFC)sheets and a rectangular bluff body with triboelectric nanogenerators(TENGs).Through a special swing-type structural design with iron blocks inside the bluff body,the GPTEH exhibits preferable aerodynamic behavior and excellent energy conversion efficiency,compared to conventional cantilever kind of piezoelectric wind energy harvester(PWEH).The GPTEH also demonstrates the capability of high output power density(PEH of 23.65 W m^(-2)and TENG of 1.59 W m^(-2)),superior response wind speed(about 0.5 m s^(-1)),and excellent long-term stability(over 14000 cyclic tests).Furthermore,a power management system is developed to efficiently utilize the output energy from GPTEH to power the sensors and wirelessly transmit environmental data to the terminals.The proposed GPTEH-powered system exhibits a great potential for the bridge environmental monitoring and Io T technologies.
文摘Machine learning models can predict material properties quickly and accurately at a low computational cost.This study generated novel hybridized nanocomposites with unsaturated polyester resin as the matrix and Areca fruit husk fiber(AFHF),tamarind fruit fiber(TFF),and nano-sized coconut shell powder(NCSP).It is challenging to determine the optimal proportion of raw materials in this composite to achieve maximum mechanical properties.This task was accomplished with the help of ML techniques in this study.The tensile strength of the hybridized nanocomposite was increased by 134.06% compared to the neat unsaturated polyester resin at a 10:5:2 wt.% ratio,AFHF:TFF:NCSP.The stiffness and impact behavior of hybridized nanocomposites were similar.The scanning electron microscope showed homogeneous reinforcement and nanofiller distribution in the matrix.However,the hybridized nanocomposite with a 20:5:0 wt.% combination ratio had the highest strain at break of 5.98%,AFHF:TFF:NCSP.The effectiveness of recurrent neural networks and recurrent neural networks with Levenberg’s algorithm was assessed using R2,mean absolute errors,and minimum squared errors.Tensile and impact strength of hybridized nanocomposites were well predicted by the recurrent neural network with Levenberg’s model with 2 and 3 hidden layers,80 neurons and 80 neurons,respectively.A recurrent neural network model with 4 hidden layers,60 neurons,and 2 hidden layers,100 neurons predicted hybridized nanocomposites’Young’s modulus and elongation at break with maximum R2 values.The mean absolute errors and minimum squared errors were evaluated to ensure the reliability of the machine learning algorithms.The models optimize hybridized nanocomposites’mechanical properties,saving time and money during experimental characterization.
文摘为探究混合Ⅲ(HybridⅢ)假人与人体乘员约束测试装置(test device for human occupant restraint,THOR)在小偏置碰撞试验中的生物逼真度差异,对比分析了HybridⅢ假人、THOR和人体安全模型(total human model for safety,THUMS)3种乘员模型在不同小偏置碰撞模式下的碰撞响应情况.采用有限元数值模拟方法,以吸能与侧滑两种典型小偏置碰撞模式的整车模型在碰撞过程中的脉冲曲线作为边界条件;结合包含完整内饰结构的某中型轿车驾驶舱模型和HybridⅢ假人、THOR以及THUMS,构建驾驶员侧约束系统仿真模型,分析小偏置碰撞过程中乘员模型的运动学响应与损伤风险差异.与HybridⅢ假人相比,THOR躯干的整体运动趋势与THUMS近似.在损伤方面,THOR头部、脑部和下肢部位的损伤风险与THUMS更接近.THOR胸部整体压缩量要高于HybridⅢ假人和THUMS 10 mm左右;颈部损伤风险大体介于HybridⅢ假人和THUMS中间,更接近THUMS.结果表明,THOR在小偏置碰撞过程中表现出的运动趋势与预测损伤风险的能力与THUMS更接近,与HybridⅢ假人相比,在小偏置碰撞过程中展现出了更高的生物逼真度.
文摘Supercapacitors are gaining popularity due to their high cycling stability,power density,and fast charge and discharge rates.Researchers are ex-ploring electrode materials,electrolytes,and separat-ors for cost-effective energy storage systems.Ad-vances in materials science have led to the develop-ment of hybrid nanomaterials,such as combining fil-amentous carbon forms with inorganic nanoparticles,to create new charge and energy transfer processes.Notable materials for electrochemical energy-stor-age applications include MXenes,2D transition met-al carbides,and nitrides,carbon black,carbon aerogels,activated carbon,carbon nanotubes,conducting polymers,carbon fibers,and nanofibers,and graphene,because of their thermal,electrical,and mechanical properties.Carbon materials mixed with conducting polymers,ceramics,metal oxides,transition metal oxides,metal hydroxides,transition metal sulfides,trans-ition metal dichalcogenide,metal sulfides,carbides,nitrides,and biomass materials have received widespread attention due to their remarkable performance,eco-friendliness,cost-effectiveness,and renewability.This article explores the development of carbon-based hybrid materials for future supercapacitors,including electric double-layer capacitors,pseudocapacitors,and hy-brid supercapacitors.It investigates the difficulties that influence structural design,manufacturing(electrospinning,hydro-thermal/solvothermal,template-assisted synthesis,electrodeposition,electrospray,3D printing)techniques and the latest car-bon-based hybrid materials research offer practical solutions for producing high-performance,next-generation supercapacitors.
基金supported by National Natural Science Foundation of China(Grant Nos.11271157,11371171 and 11471141)the Program for New Century Excellent Talents in University of Ministry of Education of China
文摘In this paper a hybridized weak Galerkin(HWG) finite element method for solving the Stokes equations in the primary velocity-pressure formulation is introduced.The WG method uses weak functions and their weak derivatives which are defined as distributions.Weak functions and weak derivatives can be approximated by piecewise polynomials with various degrees.Different combination of polynomial spaces leads to different WG finite element methods,which makes WG methods highly flexible and efficient in practical computation.A Lagrange multiplier is introduced to provide a numerical approximation for certain derivatives of the exact solution.With this new feature,the HWG method can be used to deal with jumps of the functions and their flux easily.Optimal order error estimates are established for the corresponding HWG finite element approximations for both primal variables and the Lagrange multiplier.A Schur complement formulation of the HWG method is derived for implementation purpose.The validity of the theoretical results is demonstrated in numerical tests.
基金supported by a Horizontal Project on the Development of a Hybrid Energy Storage Simulation Model for Wind Power Based on an RT-LAB Simulation System(PH2023000190)the Inner Mongolia Natural Science Foundation Project and the Optimization of Exergy Efficiency of a Hybrid Energy Storage System with Crossover Control for Wind Power(2023JQ04).
文摘Present of wind power is sporadically and cannot be utilized as the only fundamental load of energy sources.This paper proposes a wind-solar hybrid energy storage system(HESS)to ensure a stable supply grid for a longer period.A multi-objective genetic algorithm(MOGA)and state of charge(SOC)region division for the batteries are introduced to solve the objective function and configuration of the system capacity,respectively.MATLAB/Simulink was used for simulation test.The optimization results show that for a 0.5 MW wind power and 0.5 MW photovoltaic system,with a combination of a 300 Ah lithium battery,a 200 Ah lead-acid battery,and a water storage tank,the proposed strategy reduces the system construction cost by approximately 18,000 yuan.Additionally,the cycle count of the electrochemical energy storage systemincreases from4515 to 4660,while the depth of discharge decreases from 55.37%to 53.65%,achieving shallow charging and discharging,thereby extending battery life and reducing grid voltage fluctuations significantly.The proposed strategy is a guide for stabilizing the grid connection of wind and solar power generation,capability allocation,and energy management of energy conservation systems.
基金This work was supported by Beijing Natural Science Foundation （No. 2154059）, the China Postdoctoral Science Foundation （No. 2015M570988）, the National Natural Science Foundation of China （Nos. 51472055 and 61404034）, the 2015 Annual Cooperative Project between Chinese Academy of Sdences and Industrial Technology Research Institute （No. CAS-ITRI201501）, and the ＂thousands talents＂ program for the pioneer researcher and his innovation team, China.
文摘Utilizing a nanogenerator to scavenge mechanical energy from our living environment is an effective method to solve the power source issue of portable electronics. We report a linear-grating hybridized electromagnetic-triboelectric nanogenerator for scavenging the mechanical energy generated from sliding motions to sustainably power certain portable electronics. The hybridized nano- generator consists of a slider and a stator in the structural design, and possesses a 66-segment triboelectric nanogenerator （TENG） and a 9-segment electromagnetic generator （EMG） in the functional design. At a sliding acceleration of 20 m/s2 the hybridized nanogenerator can deliver maximum powers of 102.8 mW for the TENG at a loading resistance of 0.4 Mr2 and 103.3 mW for the EMG at a loading resistance of 6 kf2. With an optimal hybridized combination of the TENG with a transformer and the EMG with a power management circuit, a 10 mF capacitor can be easily charged to 2.8 V in 20 s. A packaged hybridized nanogenerator with a light weight of 140 g and small dimensions of 12 cm× 4 cm× 1.6 cm excels in scavenging low-frequency sliding energy to sustainably power portable electronics.
