Pump chambers, normally used as dominant structures in mining engineering to insure the safety and production of un-derground coal mines, become generally deformed under conditions of deep mining. Given the geology an...Pump chambers, normally used as dominant structures in mining engineering to insure the safety and production of un-derground coal mines, become generally deformed under conditions of deep mining. Given the geology and engineering condition of Qishan Coal Mine in Xuzhou, the failure characteristics of pump chambers at the –1000 m level show that the main cause can be attributed to the spatial effect induced by intersectional chambers, where one pump is constructed per well. We developed an opti-mized design of the pump room, in which the pump wells in the traditional design are integrated into one compounding well. We suggest that the new design can limit the spatial effect of intersectional chambers during construction given our relevant numerical simulation. The new design is able to simplify the structure of the pump chamber and reduce the amount of excavation required. Based on a bolt-mesh-anchor with a rigid gap coupling supporting technology, the stability of pump chamber can be improved greatly.展开更多
The plow of the submarine plowing trencher is one of the main functional mechanisms, and its optimization is very important. The design parameters play a very significant role in determining the requirements of the to...The plow of the submarine plowing trencher is one of the main functional mechanisms, and its optimization is very important. The design parameters play a very significant role in determining the requirements of the towing force of a vessel. A multi-objective genetic algorithm based on analytical models of the plow surface has been examined and applied in efforts to obtain optimal design of the plow. For a specific soil condition, the draft force and moldboard surface area which are the key parameters in the working process of the plow are optimized by finding the corresponding optimal values of the plow blade penetration angle and two surface angles of the main cutting blade of the plow. Parameters such as the moldboard side angle of deviation, moldboard lift angle, angular variation of the tangent line, and the spanning length are also analyzed with respect to the force of the moldboard surface along soil flow direction. Results show that the optimized plow has an improved plow performance. The draft forces of the main cutting blade and the moldboard are 10.6% and 7%, respectively, less than the original design. The standard deviation of Gaussian curvature of moldboard is lowered by 64.5%, which implies that the smoothness of the optimized moldboard surface is much greater than the original.展开更多
To quantify the seismic effectiveness of the most commonly used fishing line tie up method for securing museum collections and optimize fixed strategies for exhibitions,shaking table tests of the seismic systems used ...To quantify the seismic effectiveness of the most commonly used fishing line tie up method for securing museum collections and optimize fixed strategies for exhibitions,shaking table tests of the seismic systems used for typical museum collection replicas have been carried out.The influence of body shape and fixed measure parameters on the seismic responses of replicas and the interaction behavior between replicas and fixed measures have been explored.Based on the results,seismic effectiveness evaluation indexes of the tie up method are proposed.Reasonable suggestions for fixed strategies are given,which provide a basis for the exhibition of delicate museum collections considering the principle of minimizing seismic responses and intervention.The analysis results show that a larger ratio of height of mass center to bottom diameter led to more intense rocking responses.Increasing the initial pretension of fishing lines was conducive to reducing the seismic responses and stress variation of the lines.Through comprehensive consideration of the interaction forces and effective securement,it is recommended to apply 20%of breaking stress as the initial pretension.For specific museum collections that cannot be effectively protected by the independent tie up method,an optimized strategy of a combination of fishing lines and fasteners is recommended.展开更多
A mathematical model has been established for the research on scissor elevator for ship passenger stairs.The kinematical and kinetic simulation analyses were carried out with MATLAB/Simulink.The relative kinetic relat...A mathematical model has been established for the research on scissor elevator for ship passenger stairs.The kinematical and kinetic simulation analyses were carried out with MATLAB/Simulink.The relative kinetic relation between hydraulic cylinder and other parts,as well as its rules of change has been found.A 3-D model of ship scissor elevator was established with Pro/E.The design of the mechanism was optimized in Pro/MECHANICA based on the findings from simulation analysis.Practice has proved that the design is scientific and reasonable and could serve as the theoretical guidance and reference for the design of scissor mechanism of other uses.展开更多
Introduction Blood flow provides a mechanical condition for blood cells and vessels,especially for endothelial cells.It is important to understand the mechanical characteristics of
Concepts for a virtual 3D space and a hyper-sphere are proposed and the formulae for determining the computable nodes of the mesh are derived.Then a new optimization design method('Virtual Mesh Method'or V.M.M...Concepts for a virtual 3D space and a hyper-sphere are proposed and the formulae for determining the computable nodes of the mesh are derived.Then a new optimization design method('Virtual Mesh Method'or V.M.M)is developed.Three examples are given,showing that the method proposed is especially suitable for the optimized design of complex structures,and that the global approximate optimal solution can be searched with remarkably reduced computational work.展开更多
Surface morphology of Ceratocanthus beetle elytra was investigated for spike surface texture and its geometry using Scanning Electron Microscopy(SEM).Material properties were analyzed for both surface and cross-sectio...Surface morphology of Ceratocanthus beetle elytra was investigated for spike surface texture and its geometry using Scanning Electron Microscopy(SEM).Material properties were analyzed for both surface and cross-section of elytra using nano-indentation technique.The spike texture was significantly rigid compared with the non-textured zone;a bi-layer system of E and H was identified at the elytra cross-section.Normal load acting on spike texture during free-fall conditions was estimated analytically and deflection equation was derived.The design of spike texture with conical base was studied for minimization of deflection and volume using the Non-dominated Sorting Genetic Algorithm(NSGA-II)optimization technique,confirming the smart design of the natural solution.The frictional behavior of elytra was studied using fundamental tribology test and the role of the oriented spike texture was investigated for frictional anisotropy.Compression resistance of full beetle was evaluated for both conglobated and non-conglobated configuration and tensile strengths were compared using Brazilian test.Puncture and wear resistance of full elytra were characterized and correlated with its defense mechanism.展开更多
In order to improve the accuracy and stability of transplanting machine seedling picking,a seedling pick-up mechanism was designed,which was controlled by a controller and driven by brushless DC servo motor.At the sam...In order to improve the accuracy and stability of transplanting machine seedling picking,a seedling pick-up mechanism was designed,which was controlled by a controller and driven by brushless DC servo motor.At the same time,the parameters of the seedling manipulator were optimized:the mathematical model for the seedling pick-up mechanism was established.According to the predetermined trajectory requirements,the objective function and constraint conditions were proposed,and then the optimal size was obtained by a multi-objective genetic algorithm.At last,Automatic Dynamic Analysis of Mechanical Systems(ADAMS)software was used to simulate and analyze the kinematics and trajectory of the seedling pick-up mechanism,and the mechanism was tested to verify the effectiveness of the mechanism prototype.The experiments showed that the success rate of seedling picking was 94.32%,the rate of acceptably planted seedlings was 96.67%,and the rate of excellently planted seedlings was 63.48%.展开更多
The forming process of biomass fuel pellets using a ring mold pelletizer was analyzed,optimized,tested and evaluated in this study.The effects of stress amplitude and the stress ratio on the fatigue failure of the rin...The forming process of biomass fuel pellets using a ring mold pelletizer was analyzed,optimized,tested and evaluated in this study.The effects of stress amplitude and the stress ratio on the fatigue failure of the ring mold under 4-,3-,and 2-roller designs were investigated.Depending on the calculation of stress amplitude acting on the ring mold,the 4-roller design was chosen for having the smallest value of stress amplitude in this condition.After determining the main design parameters,a three-dimensional model of the ring mold pelletizer was established based on the Pro/Engineer software,and the model was transferred into ADAMS software through Mechanism/Pro which is a dedicated interface software.The ADAMS software was used to run simulations.In order to obtain the highest efficiency and the lowest power consumption,the optimal result was the 4-roller design.Finally,a prototype of the ring mold pelletizer with four rollers was designed and manufactured for biomass fuel pellet production.Corn stover biomass was used as material for experimental manufacturing of fuel pellets.Test and evaluation showed that the optimized pellet durability was 99.79%with ground corn stover particles passing a screen size of 1.97 mm,moisture content of 21.2%w.b.and a material moisture conditioning time of 3.82 h.Pellets formed in the prototype ring mold pelletizer using corn stover had acceptable durability according to European standards.展开更多
In this paper,a design is presented for a high-speed,high-power motor for a four-legged robot actuator that was optimized using the weighted sum method(WSM)based on the Taguchi method,and the response surface method(R...In this paper,a design is presented for a high-speed,high-power motor for a four-legged robot actuator that was optimized using the weighted sum method(WSM)based on the Taguchi method,and the response surface method(RSM).First,output torque,torque constant,torque ripple,and efficiency were selected as objective functions for the optimized design.The sampling method was implemented to use a mixed orthogonal array and the single response characteristics of each objective function were compared using the Taguchi method.Moreover,to consider the multi-response characteristic of the objective functions,WSM was applied.Second,the 2D finite element analysis result of the RSM was compared with that using the WSM.Finally,an experiment was carried out on the manufactured motor and the optimized model is presented here.展开更多
A large lateral shearing distance of parallel beam-splitting prism is often needed in laser modulation and polarization interference. In this letter, we present an optimized design of parallel beam-splitting prism and...A large lateral shearing distance of parallel beam-splitting prism is often needed in laser modulation and polarization interference. In this letter, we present an optimized design of parallel beam-splitting prism and list some different cases in detail. The optimized design widens the use range of parallel beam-splitting prism. At the wavelength of 632.8 nm, the law that the enlargement ratio changes with the refractive index and the apex angle is verified.展开更多
The transplanting arm of two-arm transplanting mechanism is easy to cause seedlings injury and missing due to its faster speed relative to the seedlings.In order to solve the existed problems,a three-arm transplanting...The transplanting arm of two-arm transplanting mechanism is easy to cause seedlings injury and missing due to its faster speed relative to the seedlings.In order to solve the existed problems,a three-arm transplanting mechanism for rice potted seedlings was developed in this study.The developed three-arm transplanting mechanism for rice potted seedling can make the transplanting arm realize special trajectory and attitude through the unequal planetary gear transmission.The kinematic model of three-arm transplanting mechanism for rice potted seedling was established,and the optimal design software was developed.Based on the heuristic optimization algorithm named“parameter guide”,a set of satisfied mechanism parameters required by the rice potted seedling transplanting were obtained.The trajectory and attitude of three-arm transplanting mechanism used for the rice potted seedling were analyzed.Besides,the virtual simulation results were basically consistent with the optimization software results,and the correctness of theoretical analysis and virtual simulation were also verified by each other.When the developed transplanting mechanism picked up the seedling,the velocity of transplanting arm relative to the seedling was reduced by about 30%.The results showed that the injury rate of rice potted seedling transplanting mechanism was 0.04%,the missing rate of seedling was 1.4%,the integrity rate of seedling pot matrix was 96%,and the success rate of picking seedling was 99.92%.展开更多
Mechanical weeding not only avoids crop herbicide residue but also protects the ecological environment.Compared with mechanical inter-row weeding,mechanical intra-row weeding needs to avoid crop plants,which is conduc...Mechanical weeding not only avoids crop herbicide residue but also protects the ecological environment.Compared with mechanical inter-row weeding,mechanical intra-row weeding needs to avoid crop plants,which is conducive to causing a higher rate of seedling damage.In order to realize maize(Zea mays L.)intra-row weeding,a maize intra-row weeding mechanism was designed in this study.The mechanism can detect maize seedlings by infrared beam tube,then a sliding-cutting bevel tool moves spirally amid maize seedlings,so as to eradicate intra-row weeds.A field experiment was conducted under the following experimental conditions:the bevel tool rotation speed was 800-1400 r/min,the mechanism forward speed was 4-7 km/h,and the bevel tool depth was 2-14 cm,the experimental results illustrated that the mechanism’s average weeding rate and seedling damage rate were 95.8%and 0.6%,respectively.The variance analysis showed that the primary and secondary factors that affecting the weeding rate and seedling damage rate were the same,which were bevel tool rotation speed,mechanism forward speed,bevel tool depth in soil in a descending order according to the significances.The result of the field experiment may provide a reference for intra-row weeding device design.展开更多
The vacuum vessel of the HT-7U superconducting tokamak will be a fully-welded structure with a double-wall. The space between the double-wall will be filled with borated water for neutron shielding. Non-circular cross...The vacuum vessel of the HT-7U superconducting tokamak will be a fully-welded structure with a double-wall. The space between the double-wall will be filled with borated water for neutron shielding. Non-circular cross-section is designed for plasma elongating. Horizontal and vertical ports are designed for diagnosing, vacuum pumping, plasma heating and plasma current driving, etc. The vacuum vessel consists of 16 segments. It will be baked out at 250℃ to obtain a clean wall. When the machine is in operation, both the hot wall (the wall temperature is around 100℃) and the cold wall (wall temperature is in normal equilibrium) are considered. The stress caused by thermal deformation and the electromagnetic (EM) loads caused by 1.5 MA plasma disruption in 3.5 T magnetic field have to be taken into account in the design of the HT-7U vacuum vessel Finite element method was employed for structure analysis of the vacuum vessel.展开更多
The glass curtain wall is widely favored by the owners for its good appearance modeling efthct. In using process, however, excessive energy consumption, low level indoor eomtort and other problems of glass curtain wal...The glass curtain wall is widely favored by the owners for its good appearance modeling efthct. In using process, however, excessive energy consumption, low level indoor eomtort and other problems of glass curtain wall are often exposed. Aiming at office buildings in hot Summer and cold Winter zone, taking the optimization of thermal comfort of double glass curtain wall in the summer and the reduetion of building energy consumption throughout the year as the breakthrough point, using the method of energy simulation analysis, through changing the size of internal shading component in the simulated room, this paper analyzes and summarizes the variation law of its energy consumption value, to explore the relatively reasonable design plan of shading systems of the building with glass curtain wall.展开更多
The umbilical,a key component in offshore energy extraction,plays a vital role in ensuring the stable operation of the entire production system.The extensive variety of cross-sectional components creates highly comple...The umbilical,a key component in offshore energy extraction,plays a vital role in ensuring the stable operation of the entire production system.The extensive variety of cross-sectional components creates highly complex layout combinations.Furthermore,due to constraints in component quantity and geometry within the cross-sectional layout,filler bodies must be incorporated to maintain cross-section performance.Conventional design approaches based on manual experience suffer from inefficiency,high variability,and difficulties in quantification.This paper presents a multi-level automatic filling optimization design method for umbilical cross-sectional layouts to address these limitations.Initially,the research establishes a multi-objective optimization model that considers compactness,balance,and wear resistance of the cross-section,employing an enhanced genetic algorithm to achieve a near-optimal layout.Subsequently,the study implements an image processing-based vacancy detection technique to accurately identify cross-sectional gaps.To manage the variability and diversity of these vacant regions,the research introduces a multi-level filling method that strategically selects and places filler bodies of varying dimensions,overcoming the constraints of uniform-size fillers.Additionally,the method incorporates a hierarchical strategy that subdivides the complex cross-section into multiple layers,enabling layer-by-layer optimization and filling.This approach reduces manufac-turing equipment requirements while ensuring practical production process feasibility.The methodology is validated through a specific umbilical case study.The results demonstrate improvements in compactness,balance,and wear resistance compared with the initial cross-section,offering novel insights and valuable references for filler design in umbilical cross-sections.展开更多
The work takes a new liquid-cooling plate in a power battery with pin fins inside the channel as the object.A mathematical model is established via the central composite design of the response surface to study the rel...The work takes a new liquid-cooling plate in a power battery with pin fins inside the channel as the object.A mathematical model is established via the central composite design of the response surface to study the relationships among the length,width,height,and spacing of pin fins;the maximum temperature and temperature difference of the battery module;and the pressure drop of the liquid-cooling plate.Model accuracy is verified via variance analysis.The new liquid-cooling plate enables the power battery to work within an optimal temperature range.Appropriately increasing the length,width,and height and reducing the spacing of pin fins could reduce the temperature of the power battery module and improve the temperature uniformity.However,the pressure drop of the liquid-cooling plate increases.The structural parameters of the pin fins are optimized to minimize the maximum temperature and the temperature difference of the battery module as well as the pressure drop of the liquid-cooling plate.The errors between the values predicted and actual by the simulation test are 0.58%,4%,and 0.48%,respectively,which further verifies the model accuracy.The results reveal the influence of the structural parameters of the pin fins inside the liquid-cooling plate on its heat dissipation performance and pressure drop characteristics.A theoretical basis is provided for the design of liquid-cooling plates in power batteries and the optimization of structural parameters.展开更多
In order to accurately forecast the main engine fuel consumption and reduce the Energy Efficiency Operational Indicator(EEOI)of merchant ships in polar ice areas,the energy transfer relationship between ship-machine-p...In order to accurately forecast the main engine fuel consumption and reduce the Energy Efficiency Operational Indicator(EEOI)of merchant ships in polar ice areas,the energy transfer relationship between ship-machine-propeller is studied by analyzing the complex force situation during ship navigation and building a MATLAB/Simulink simulation platform based on multi-environmental resistance,propeller efficiency,main engine power,fuel consumption,fuel consumption rate and EEOI calculation module.Considering the environmental factors of wind,wave and ice,the route is divided into sections,the calculation of main engine power,main engine fuel consumption and EEOI for each section is completed,and the speed design is optimized based on the simulation model for each section.Under the requirements of the voyage plan,the optimization results show that the energy efficiency operation index of the whole route is reduced by 3.114%and the fuel consumption is reduced by 9.17 t.展开更多
G protein coupled receptor kinase 2 (GRK2) is a kinase that regulates cardiac signaling activity. Inhibiting GRK2 is a promising mechanism for the treatment of heart failure (HF). Further development and optimization ...G protein coupled receptor kinase 2 (GRK2) is a kinase that regulates cardiac signaling activity. Inhibiting GRK2 is a promising mechanism for the treatment of heart failure (HF). Further development and optimization of inhibitors targeting GRK2 are highly meaningful. Therefore, in order to design GRK2 inhibitors with better performance, the most active molecule was selected as a reference compound from a data set containing 4-pyridylhydrazone derivatives and triazole derivatives, and its scaffold was extracted as the initial scaffold. Then, a powerful optimization-based framework for de novo drug design, guided by binding affinity, was used to generate a virtual molecular library targeting GRK2. The binding affinity of each virtual compound in this dataset was predicted by our developed deep learning model, and the designed potential compound with high binding affinity was selected for molecular docking and molecular dynamics simulation. It was found that the designed potential molecule binds to the ATP site of GRK2, which consists of key amino acids including Arg199, Gly200, Phe202, Val205, Lys220, Met274 and Asp335. The scaffold of the molecule is stabilized mainly by H-bonding and hydrophobic contacts. Concurrently, the reference compound in the dataset was also simulated by docking. It was found that this molecule also binds to the ATP site of GRK2. In addition, its scaffold is stabilized mainly by H-bonding and π-cation stacking interactions with Lys220, as well as hydrophobic contacts. The above results show that the designed potential molecule has similar binding modes to the reference compound, supporting the effectiveness of our framework for activity-focused molecular design. Finally, we summarized the interaction characteristics of general GRK2 inhibitors and gained insight into their molecule-target binding mechanisms, thereby facilitating the expansion of lead to hit compound.展开更多
Inflatable deployable structures inspired by origami have significant applications in space missions such as solar arrays and antennas.In this paper,a generalized Miura-ori tubular cell(GMTC)is presented as the basic ...Inflatable deployable structures inspired by origami have significant applications in space missions such as solar arrays and antennas.In this paper,a generalized Miura-ori tubular cell(GMTC)is presented as the basic cell to design a family of inflatable origami tubular structures with the targeted configuration.First,the classification of rigid foldable degree-4 vertices is studied thoroughly.Since the proposed GMTC is comprised of forming units(FU)and linking units(LU),types of FUs and LUs are investigated based on the classification of degree-4 vertices,respectively.The rigid foldability of the GMTC is presented by studying the kinematics of the FUs and LUs.Volume of the GMTC is analyzed to investigate multistable configurations of the basic cell.The variations in volume of the GMTC offer great potential for developing the inflatable tubular structure.Design method and parametric optimization of the tubular structure with targeted configuration are proposed.The feasibility of the approach is validated by the approximation of four different cases,namely parabolic,semicircular,trapezoidal,and straight-arc hybrid tubular structures.展开更多
基金supported by the Major Project of the National Basic Research Program of China (No2006CB202200)the Program for New Century Excellent Talents in Uni-versity (NoNCET07-0800)the Special Fund for Basic Research and Operating Expenses of the China University of Mining & Technology, Beijing and the Academician workstation in enterprise of Jiangsu Province (No.BM2009563)
文摘Pump chambers, normally used as dominant structures in mining engineering to insure the safety and production of un-derground coal mines, become generally deformed under conditions of deep mining. Given the geology and engineering condition of Qishan Coal Mine in Xuzhou, the failure characteristics of pump chambers at the –1000 m level show that the main cause can be attributed to the spatial effect induced by intersectional chambers, where one pump is constructed per well. We developed an opti-mized design of the pump room, in which the pump wells in the traditional design are integrated into one compounding well. We suggest that the new design can limit the spatial effect of intersectional chambers during construction given our relevant numerical simulation. The new design is able to simplify the structure of the pump chamber and reduce the amount of excavation required. Based on a bolt-mesh-anchor with a rigid gap coupling supporting technology, the stability of pump chamber can be improved greatly.
基金Supported the National Natural Science Foundation of China （No. 51179040） Natural Science Foundation of Heilongjiang Province （No. E200904）
文摘The plow of the submarine plowing trencher is one of the main functional mechanisms, and its optimization is very important. The design parameters play a very significant role in determining the requirements of the towing force of a vessel. A multi-objective genetic algorithm based on analytical models of the plow surface has been examined and applied in efforts to obtain optimal design of the plow. For a specific soil condition, the draft force and moldboard surface area which are the key parameters in the working process of the plow are optimized by finding the corresponding optimal values of the plow blade penetration angle and two surface angles of the main cutting blade of the plow. Parameters such as the moldboard side angle of deviation, moldboard lift angle, angular variation of the tangent line, and the spanning length are also analyzed with respect to the force of the moldboard surface along soil flow direction. Results show that the optimized plow has an improved plow performance. The draft forces of the main cutting blade and the moldboard are 10.6% and 7%, respectively, less than the original design. The standard deviation of Gaussian curvature of moldboard is lowered by 64.5%, which implies that the smoothness of the optimized moldboard surface is much greater than the original.
基金Beijing Nova Program under Grant No.2022036National Key Research and Development Program under Grant No.2019YFC1521000。
文摘To quantify the seismic effectiveness of the most commonly used fishing line tie up method for securing museum collections and optimize fixed strategies for exhibitions,shaking table tests of the seismic systems used for typical museum collection replicas have been carried out.The influence of body shape and fixed measure parameters on the seismic responses of replicas and the interaction behavior between replicas and fixed measures have been explored.Based on the results,seismic effectiveness evaluation indexes of the tie up method are proposed.Reasonable suggestions for fixed strategies are given,which provide a basis for the exhibition of delicate museum collections considering the principle of minimizing seismic responses and intervention.The analysis results show that a larger ratio of height of mass center to bottom diameter led to more intense rocking responses.Increasing the initial pretension of fishing lines was conducive to reducing the seismic responses and stress variation of the lines.Through comprehensive consideration of the interaction forces and effective securement,it is recommended to apply 20%of breaking stress as the initial pretension.For specific museum collections that cannot be effectively protected by the independent tie up method,an optimized strategy of a combination of fishing lines and fasteners is recommended.
文摘A mathematical model has been established for the research on scissor elevator for ship passenger stairs.The kinematical and kinetic simulation analyses were carried out with MATLAB/Simulink.The relative kinetic relation between hydraulic cylinder and other parts,as well as its rules of change has been found.A 3-D model of ship scissor elevator was established with Pro/E.The design of the mechanism was optimized in Pro/MECHANICA based on the findings from simulation analysis.Practice has proved that the design is scientific and reasonable and could serve as the theoretical guidance and reference for the design of scissor mechanism of other uses.
基金supported by grant from National Natural Science Foundation of China No10772127,30570450Program for New Century Excellent Talents in University NCET-06-0789Sichaun Youth Science and Technology Foundation 06ZQ026-009
文摘Introduction Blood flow provides a mechanical condition for blood cells and vessels,especially for endothelial cells.It is important to understand the mechanical characteristics of
基金Project supported by the Natural Science Foundation of Henan Province,China(No.0311010400).
文摘Concepts for a virtual 3D space and a hyper-sphere are proposed and the formulae for determining the computable nodes of the mesh are derived.Then a new optimization design method('Virtual Mesh Method'or V.M.M)is developed.Three examples are given,showing that the method proposed is especially suitable for the optimized design of complex structures,and that the global approximate optimal solution can be searched with remarkably reduced computational work.
基金supported by Ministero Universitàe Ricerca(MUR-PRIN 20222022ATZCJN AMPHYBIA)CUP N.E53D23003040006Ministero dell'istruzione dell'universitàe della ricerca(MIUR-PON 2018 PROSCAN)CUP N.E96C18000440008European Union NextGenerationEU PNRR Spoke 7 CN00000013 HPC CUP N.E63C22000970007.
文摘Surface morphology of Ceratocanthus beetle elytra was investigated for spike surface texture and its geometry using Scanning Electron Microscopy(SEM).Material properties were analyzed for both surface and cross-section of elytra using nano-indentation technique.The spike texture was significantly rigid compared with the non-textured zone;a bi-layer system of E and H was identified at the elytra cross-section.Normal load acting on spike texture during free-fall conditions was estimated analytically and deflection equation was derived.The design of spike texture with conical base was studied for minimization of deflection and volume using the Non-dominated Sorting Genetic Algorithm(NSGA-II)optimization technique,confirming the smart design of the natural solution.The frictional behavior of elytra was studied using fundamental tribology test and the role of the oriented spike texture was investigated for frictional anisotropy.Compression resistance of full beetle was evaluated for both conglobated and non-conglobated configuration and tensile strengths were compared using Brazilian test.Puncture and wear resistance of full elytra were characterized and correlated with its defense mechanism.
基金This research was supported by the National Natural Science Foundation of China(Grant No.51775104).
文摘In order to improve the accuracy and stability of transplanting machine seedling picking,a seedling pick-up mechanism was designed,which was controlled by a controller and driven by brushless DC servo motor.At the same time,the parameters of the seedling manipulator were optimized:the mathematical model for the seedling pick-up mechanism was established.According to the predetermined trajectory requirements,the objective function and constraint conditions were proposed,and then the optimal size was obtained by a multi-objective genetic algorithm.At last,Automatic Dynamic Analysis of Mechanical Systems(ADAMS)software was used to simulate and analyze the kinematics and trajectory of the seedling pick-up mechanism,and the mechanism was tested to verify the effectiveness of the mechanism prototype.The experiments showed that the success rate of seedling picking was 94.32%,the rate of acceptably planted seedlings was 96.67%,and the rate of excellently planted seedlings was 63.48%.
基金the financial support received from the China Scholarship Council(201308210283)the national Spark Program(2015GA650012)+1 种基金the Cultivation Plan for Youth Agricultural Science and Technology Innovative Talents of Liaoning Province(2014053)the funding provided by Youth Fund of Shenyang Agricultural University(20121002)。
文摘The forming process of biomass fuel pellets using a ring mold pelletizer was analyzed,optimized,tested and evaluated in this study.The effects of stress amplitude and the stress ratio on the fatigue failure of the ring mold under 4-,3-,and 2-roller designs were investigated.Depending on the calculation of stress amplitude acting on the ring mold,the 4-roller design was chosen for having the smallest value of stress amplitude in this condition.After determining the main design parameters,a three-dimensional model of the ring mold pelletizer was established based on the Pro/Engineer software,and the model was transferred into ADAMS software through Mechanism/Pro which is a dedicated interface software.The ADAMS software was used to run simulations.In order to obtain the highest efficiency and the lowest power consumption,the optimal result was the 4-roller design.Finally,a prototype of the ring mold pelletizer with four rollers was designed and manufactured for biomass fuel pellet production.Corn stover biomass was used as material for experimental manufacturing of fuel pellets.Test and evaluation showed that the optimized pellet durability was 99.79%with ground corn stover particles passing a screen size of 1.97 mm,moisture content of 21.2%w.b.and a material moisture conditioning time of 3.82 h.Pellets formed in the prototype ring mold pelletizer using corn stover had acceptable durability according to European standards.
基金supported by the Industrial Strategic Technology Development Program(10070171,Development of core technology for advanced locomotion/manipulation based on high-speed/power robot platform and robot intelligence)funded By the Ministry of Trade,Industry&Energy(MI,Korea).
文摘In this paper,a design is presented for a high-speed,high-power motor for a four-legged robot actuator that was optimized using the weighted sum method(WSM)based on the Taguchi method,and the response surface method(RSM).First,output torque,torque constant,torque ripple,and efficiency were selected as objective functions for the optimized design.The sampling method was implemented to use a mixed orthogonal array and the single response characteristics of each objective function were compared using the Taguchi method.Moreover,to consider the multi-response characteristic of the objective functions,WSM was applied.Second,the 2D finite element analysis result of the RSM was compared with that using the WSM.Finally,an experiment was carried out on the manufactured motor and the optimized model is presented here.
文摘A large lateral shearing distance of parallel beam-splitting prism is often needed in laser modulation and polarization interference. In this letter, we present an optimized design of parallel beam-splitting prism and list some different cases in detail. The optimized design widens the use range of parallel beam-splitting prism. At the wavelength of 632.8 nm, the law that the enlargement ratio changes with the refractive index and the apex angle is verified.
基金supported by the National Natural Science Foundation of China(Grant No.52005221)the Natural Science Foundation of Jiangsu Province(Grant No.BK20200897)the China Postdoctoral Science Foundation(Grant No.2021M691315).
文摘The transplanting arm of two-arm transplanting mechanism is easy to cause seedlings injury and missing due to its faster speed relative to the seedlings.In order to solve the existed problems,a three-arm transplanting mechanism for rice potted seedlings was developed in this study.The developed three-arm transplanting mechanism for rice potted seedling can make the transplanting arm realize special trajectory and attitude through the unequal planetary gear transmission.The kinematic model of three-arm transplanting mechanism for rice potted seedling was established,and the optimal design software was developed.Based on the heuristic optimization algorithm named“parameter guide”,a set of satisfied mechanism parameters required by the rice potted seedling transplanting were obtained.The trajectory and attitude of three-arm transplanting mechanism used for the rice potted seedling were analyzed.Besides,the virtual simulation results were basically consistent with the optimization software results,and the correctness of theoretical analysis and virtual simulation were also verified by each other.When the developed transplanting mechanism picked up the seedling,the velocity of transplanting arm relative to the seedling was reduced by about 30%.The results showed that the injury rate of rice potted seedling transplanting mechanism was 0.04%,the missing rate of seedling was 1.4%,the integrity rate of seedling pot matrix was 96%,and the success rate of picking seedling was 99.92%.
基金supported by the National Natural Science Foundation of China(Grant No.31901408).
文摘Mechanical weeding not only avoids crop herbicide residue but also protects the ecological environment.Compared with mechanical inter-row weeding,mechanical intra-row weeding needs to avoid crop plants,which is conducive to causing a higher rate of seedling damage.In order to realize maize(Zea mays L.)intra-row weeding,a maize intra-row weeding mechanism was designed in this study.The mechanism can detect maize seedlings by infrared beam tube,then a sliding-cutting bevel tool moves spirally amid maize seedlings,so as to eradicate intra-row weeds.A field experiment was conducted under the following experimental conditions:the bevel tool rotation speed was 800-1400 r/min,the mechanism forward speed was 4-7 km/h,and the bevel tool depth was 2-14 cm,the experimental results illustrated that the mechanism’s average weeding rate and seedling damage rate were 95.8%and 0.6%,respectively.The variance analysis showed that the primary and secondary factors that affecting the weeding rate and seedling damage rate were the same,which were bevel tool rotation speed,mechanism forward speed,bevel tool depth in soil in a descending order according to the significances.The result of the field experiment may provide a reference for intra-row weeding device design.
文摘The vacuum vessel of the HT-7U superconducting tokamak will be a fully-welded structure with a double-wall. The space between the double-wall will be filled with borated water for neutron shielding. Non-circular cross-section is designed for plasma elongating. Horizontal and vertical ports are designed for diagnosing, vacuum pumping, plasma heating and plasma current driving, etc. The vacuum vessel consists of 16 segments. It will be baked out at 250℃ to obtain a clean wall. When the machine is in operation, both the hot wall (the wall temperature is around 100℃) and the cold wall (wall temperature is in normal equilibrium) are considered. The stress caused by thermal deformation and the electromagnetic (EM) loads caused by 1.5 MA plasma disruption in 3.5 T magnetic field have to be taken into account in the design of the HT-7U vacuum vessel Finite element method was employed for structure analysis of the vacuum vessel.
文摘The glass curtain wall is widely favored by the owners for its good appearance modeling efthct. In using process, however, excessive energy consumption, low level indoor eomtort and other problems of glass curtain wall are often exposed. Aiming at office buildings in hot Summer and cold Winter zone, taking the optimization of thermal comfort of double glass curtain wall in the summer and the reduetion of building energy consumption throughout the year as the breakthrough point, using the method of energy simulation analysis, through changing the size of internal shading component in the simulated room, this paper analyzes and summarizes the variation law of its energy consumption value, to explore the relatively reasonable design plan of shading systems of the building with glass curtain wall.
基金financially supported by Guangdong Province Basic and Applied Basic Research Fund Project(Grant No.2022B1515250009)Liaoning Provincial Natural Science Foundation-Doctoral Research Start-up Fund Project(Grant No.2024-BSBA-05)+1 种基金Major Science and Technology Innovation Project in Shandong Province(Grant No.2024CXGC010803)the National Natural Science Foundation of China(Grant Nos.52271269 and 12302147).
文摘The umbilical,a key component in offshore energy extraction,plays a vital role in ensuring the stable operation of the entire production system.The extensive variety of cross-sectional components creates highly complex layout combinations.Furthermore,due to constraints in component quantity and geometry within the cross-sectional layout,filler bodies must be incorporated to maintain cross-section performance.Conventional design approaches based on manual experience suffer from inefficiency,high variability,and difficulties in quantification.This paper presents a multi-level automatic filling optimization design method for umbilical cross-sectional layouts to address these limitations.Initially,the research establishes a multi-objective optimization model that considers compactness,balance,and wear resistance of the cross-section,employing an enhanced genetic algorithm to achieve a near-optimal layout.Subsequently,the study implements an image processing-based vacancy detection technique to accurately identify cross-sectional gaps.To manage the variability and diversity of these vacant regions,the research introduces a multi-level filling method that strategically selects and places filler bodies of varying dimensions,overcoming the constraints of uniform-size fillers.Additionally,the method incorporates a hierarchical strategy that subdivides the complex cross-section into multiple layers,enabling layer-by-layer optimization and filling.This approach reduces manufac-turing equipment requirements while ensuring practical production process feasibility.The methodology is validated through a specific umbilical case study.The results demonstrate improvements in compactness,balance,and wear resistance compared with the initial cross-section,offering novel insights and valuable references for filler design in umbilical cross-sections.
基金supported by the Education and Teaching Research Project of Universities in Fujian Province(FBJY20230167).
文摘The work takes a new liquid-cooling plate in a power battery with pin fins inside the channel as the object.A mathematical model is established via the central composite design of the response surface to study the relationships among the length,width,height,and spacing of pin fins;the maximum temperature and temperature difference of the battery module;and the pressure drop of the liquid-cooling plate.Model accuracy is verified via variance analysis.The new liquid-cooling plate enables the power battery to work within an optimal temperature range.Appropriately increasing the length,width,and height and reducing the spacing of pin fins could reduce the temperature of the power battery module and improve the temperature uniformity.However,the pressure drop of the liquid-cooling plate increases.The structural parameters of the pin fins are optimized to minimize the maximum temperature and the temperature difference of the battery module as well as the pressure drop of the liquid-cooling plate.The errors between the values predicted and actual by the simulation test are 0.58%,4%,and 0.48%,respectively,which further verifies the model accuracy.The results reveal the influence of the structural parameters of the pin fins inside the liquid-cooling plate on its heat dissipation performance and pressure drop characteristics.A theoretical basis is provided for the design of liquid-cooling plates in power batteries and the optimization of structural parameters.
文摘In order to accurately forecast the main engine fuel consumption and reduce the Energy Efficiency Operational Indicator(EEOI)of merchant ships in polar ice areas,the energy transfer relationship between ship-machine-propeller is studied by analyzing the complex force situation during ship navigation and building a MATLAB/Simulink simulation platform based on multi-environmental resistance,propeller efficiency,main engine power,fuel consumption,fuel consumption rate and EEOI calculation module.Considering the environmental factors of wind,wave and ice,the route is divided into sections,the calculation of main engine power,main engine fuel consumption and EEOI for each section is completed,and the speed design is optimized based on the simulation model for each section.Under the requirements of the voyage plan,the optimization results show that the energy efficiency operation index of the whole route is reduced by 3.114%and the fuel consumption is reduced by 9.17 t.
基金supported by the National Natural Science Foundation of China Excellent Young Scientist Fund(22422801)the National Natural Science Foundation of China General Project(22278053)+1 种基金the National Natural Science Foundation of China General Project(22078041)Dalian High-level Talents Innovation Support Program(2023RQ059).
文摘G protein coupled receptor kinase 2 (GRK2) is a kinase that regulates cardiac signaling activity. Inhibiting GRK2 is a promising mechanism for the treatment of heart failure (HF). Further development and optimization of inhibitors targeting GRK2 are highly meaningful. Therefore, in order to design GRK2 inhibitors with better performance, the most active molecule was selected as a reference compound from a data set containing 4-pyridylhydrazone derivatives and triazole derivatives, and its scaffold was extracted as the initial scaffold. Then, a powerful optimization-based framework for de novo drug design, guided by binding affinity, was used to generate a virtual molecular library targeting GRK2. The binding affinity of each virtual compound in this dataset was predicted by our developed deep learning model, and the designed potential compound with high binding affinity was selected for molecular docking and molecular dynamics simulation. It was found that the designed potential molecule binds to the ATP site of GRK2, which consists of key amino acids including Arg199, Gly200, Phe202, Val205, Lys220, Met274 and Asp335. The scaffold of the molecule is stabilized mainly by H-bonding and hydrophobic contacts. Concurrently, the reference compound in the dataset was also simulated by docking. It was found that this molecule also binds to the ATP site of GRK2. In addition, its scaffold is stabilized mainly by H-bonding and π-cation stacking interactions with Lys220, as well as hydrophobic contacts. The above results show that the designed potential molecule has similar binding modes to the reference compound, supporting the effectiveness of our framework for activity-focused molecular design. Finally, we summarized the interaction characteristics of general GRK2 inhibitors and gained insight into their molecule-target binding mechanisms, thereby facilitating the expansion of lead to hit compound.
基金supported by the National Natural Science Foundation of China(No.52222501,52075016,52192632)the Fundamental Research Funds for the Central Universities(Grant No.YWF-23-L-904).
文摘Inflatable deployable structures inspired by origami have significant applications in space missions such as solar arrays and antennas.In this paper,a generalized Miura-ori tubular cell(GMTC)is presented as the basic cell to design a family of inflatable origami tubular structures with the targeted configuration.First,the classification of rigid foldable degree-4 vertices is studied thoroughly.Since the proposed GMTC is comprised of forming units(FU)and linking units(LU),types of FUs and LUs are investigated based on the classification of degree-4 vertices,respectively.The rigid foldability of the GMTC is presented by studying the kinematics of the FUs and LUs.Volume of the GMTC is analyzed to investigate multistable configurations of the basic cell.The variations in volume of the GMTC offer great potential for developing the inflatable tubular structure.Design method and parametric optimization of the tubular structure with targeted configuration are proposed.The feasibility of the approach is validated by the approximation of four different cases,namely parabolic,semicircular,trapezoidal,and straight-arc hybrid tubular structures.
