Previous studies have revealed that ammonia nitrogen has several adverse effects on clam Ruditapes philippinarum.However,knowledge is lacking regarding the related proteins involved in the toxicological responses,whic...Previous studies have revealed that ammonia nitrogen has several adverse effects on clam Ruditapes philippinarum.However,knowledge is lacking regarding the related proteins involved in the toxicological responses,which is vital to elucidate the underlying mechanism of ammonia nitrogen.In this study,clams R.philippinarum were exposed to ammonia nitrogen for 21 d at two environmentally relevant concentrations.The tandem mass tags approach(TMT)was applied to assay the differentially expressed proteins(DEPs)in clam gill tissues on the 3 rd and 21 st day.Finally,a total of 7263 proteins were identified.Bioinformatics analyses revealed that clam protein profiles changed in dose-and time dependent manner after ammonia nitrogen exposure.We inferred that the clams may face heavy challenges after ammonia exposure,such as unbalanced gender ratio,lysosomal disease,energy lack,neurological disorders,altered glutamine metabolism,increased lipid synthesis,and impaired immunity.Variation profiles of enzyme activities of glutaminase and glutamine synthase provided direct evidence to verify the related inference from proteome data.Most of the inferred toxic effects merit further study.This study identified important proteins related to ammonia nitrogen toxicity in the clam and indicated the severe stress of marine ammonia pollution on the healthy development of mollusc aquaculture.展开更多
Autonomous navigation is a fundamental problem in robotics.Traditional methods generally build point cloud map or dense feature map in perceptual space;due to lack of cognition and memory formation mechanism,tradition...Autonomous navigation is a fundamental problem in robotics.Traditional methods generally build point cloud map or dense feature map in perceptual space;due to lack of cognition and memory formation mechanism,traditional methods exist poor robustness and low cognitive ability.As a new navigation technology that draws inspiration from mammal’s navigation,bionic navigation method can map perceptual information into cognitive space,and have strong autonomy and environment adaptability.To improve the robot’s autonomous navigation ability,this paper proposes a cognitive map-based hierarchical navigation method.First,the mammals’navigation-related grid cells and head direction cells are modeled to provide the robots with location cognition.And then a global path planning strategy based on cognitive map is proposed,which can anticipate one preferred global path to the target with high efficiency and short distance.Moreover,a hierarchical motion controlling method is proposed,with which the target navigation can be divided into several sub-target navigation,and the mobile robot can reach to these sub-targets with high confidence level.Finally,some experiments are implemented,the results show that the proposed path planning method can avoid passing through obstacles and obtain one preferred global path to the target with high efficiency,and the time cost does not increase extremely with the increase of experience nodes number.The motion controlling results show that the mobile robot can arrive at the target successfully only depending on its self-motion information,which is an effective attempt and reflects strong bionic properties.展开更多
Contact state estimation is significant for evaluating grasp stability of bionic hands,especially in unknown environments or without visual/tactile feedback.It still remains challenging,particularly for soft bionic ha...Contact state estimation is significant for evaluating grasp stability of bionic hands,especially in unknown environments or without visual/tactile feedback.It still remains challenging,particularly for soft bionic hands without integrating complicated external sensors on soft fingers.Focusing on this issue,a proprioceptive-sensing-based systematic solution is proposed to estimate the contact state of soft bionic fingers in a single grasp.A kinematic model for soft fingers is first developed to capture the joint rotation angles and tendon displacement.A kinetostatic model is further built to estimate the contact force when soft fingers come in contact with objects.On this basis,a system stiffness model for soft fingers during preshaping and initial contact with objects is proposed to perceive the contact state.Moreover,an instantaneous stiffness model for soft fingers when initial contact occurs is developed for estimating the contact position on certain phalanges,especially the contact position along the distal phalange.The proposed proprioceptive-sensing-based approach is the first application in soft fingers without integrating complicated external sensors,which makes them concise and practical.Experiments are carried out to demonstrate the effectiveness and efficiency of our proposal.展开更多
This paper proposes an uncalibrated workpiece positioning method for peg-in-hole assembly of a device using an industrial robot.Depth images are used to identify and locate the workpieces when a peg-in-hole assembly t...This paper proposes an uncalibrated workpiece positioning method for peg-in-hole assembly of a device using an industrial robot.Depth images are used to identify and locate the workpieces when a peg-in-hole assembly task is carried out by an industrial robot in a flexible production system.First,the depth image is thresholded according to the depth data of the workpiece surface so as to filter out the background interference.Second,a series of image processing and the feature recognition algorithms are executed to extract the outer contour features and locate the center point position.This image information,fed by the vision system,will drive the robot to achieve the positioning,approximately.Finally,the Hough circle detection algorithm is used to extract the features and the relevant parameters of the circular hole where the assembly would be done,on the color image,for accurate positioning.The experimental result shows that the positioning accuracy of this method is between 0.6-1.2 mm,in the used experimental system.The entire positioning process need not require complicated calibration,and the method is highly flexible.It is suitable for the automatic assembly tasks with multi-specification or in small batches,in a flexible production system.展开更多
The interaction between organic and inorganic components in metal hybrid perovskites fundamentally determines the intrinsic optoelectronic performance.However,the underlying interaction sites have still remained elusi...The interaction between organic and inorganic components in metal hybrid perovskites fundamentally determines the intrinsic optoelectronic performance.However,the underlying interaction sites have still remained elusive,especially for those non-hydrogen-bonded hybrid perovskites,thus largely impeding materials precise design with targeted properties.Herein,high pressure is utilized to elucidate the interaction mechanism between organic and inorganic components in the as-synthesized one-dimensional hybrid metal halide(DBU)PbBr_(3)(DBU=1,8-diazabicyclo[5.4.0]undec-7-ene).The interaction sites are identified to be the N from DBU and the Br from inorganic framework by the indicative of enhanced Raman mode under high pressure.The change in interaction strength is indeed derived from the pressure modulation on both distance and spatial arrangement of the nearest Br and N,rather than traditional hydrogen-bonding effect.Furthermore,the enhanced interaction increased charge transfer,resulting in a cyan emission with photoluminescence quantum yields(PLQYs)of 86.6%.The enhanced cyan emission is particularly important for underwater communication due to the much less attenuation in water than at other wavelength emissions.This study provides deep insights into the underlying photophysical mechanism of non-hydrogen-bonded hybrid metal halides and is expected to impart innovative construction with superior performance.展开更多
A redundantly actuated parallel manipulator(RAPM)with mixed translational and rotational degrees of freedom(DOFs)is challenged for its dimensionally homogeneous Jacobian modeling and optimal design of architecture.In ...A redundantly actuated parallel manipulator(RAPM)with mixed translational and rotational degrees of freedom(DOFs)is challenged for its dimensionally homogeneous Jacobian modeling and optimal design of architecture.In this paper,a means to achieve redundant actuation by adding kinematic constraints is introduced,which reduces the DOFs of the end-effector(EE).A generic dimensionally homogeneous Jacobian is developed for this type of RAPMs,which maps the generalized velocities of three points on the EE to the joint velocities.A new optimization algorithm derived from this dimension-ally homogeneous Jacobian is proposed for the optimal design of this type of RAPMs.As an example,this paper presents a spatial RAPM involving linkages and cam mechanisms.This RAPM has 4 DOFs and 6 translational actuations.The linkage lengths and the position of the universal joints of the RAPM are optimized based on the dimensionally homogeneous Jacobian.展开更多
Masticatory robots are an effective in vitro performance testing device for dental material and mandibular prostheses.A cable-driven linear actuator(CDLA)capable of bidirectional motion is proposed in this study to de...Masticatory robots are an effective in vitro performance testing device for dental material and mandibular prostheses.A cable-driven linear actuator(CDLA)capable of bidirectional motion is proposed in this study to design a masticatory robot that can achieve increasingly human-like chewing motion.The CDLA presents remarkable advantages,such as lightweight and high stiffness structure,in using cable amplification and pulley systems.This work also exploits the proposed CDLA and designs a masticatory robot called Southeast University masticatory robot(SMAR)to solve existing problems,such as bulky driving linkage and position change of the muscle’s origin.Stiffness analysis and performance experiment validate the CDLA’s efficiency,with its stiffness reaching 1379.6 N/mm(number of cable parts n=4),which is 21.4 times the input wire stiffness.Accordingly,the CDLA’s force transmission efficiencies in two directions are 84.5%and 85.9%.Chewing experiments are carried out on the developed masticatory robot to verify whether the CDLA can help SMAR achieve a natural human-like chewing motion and sufficient chewing forces for potential applications in performance tests of dental materials or prostheses.展开更多
Facility layout problem(FLP)contemplates the optimization of space utilization,costs,and material flow.Commercial simulation softwares are commonly used to validate layouts by simulating the real world material flow a...Facility layout problem(FLP)contemplates the optimization of space utilization,costs,and material flow.Commercial simulation softwares are commonly used to validate layouts by simulating the real world material flow and production process.To validate a layout scenario of a solar module assembly workshop,a 3D simulation model is presented which was designed on VisualComponents software.To begin with,we introduce the layout characteristics and use the systematic layout planning(SLP)method to design the block layout of workshop.Then,we built components library which contains all the facilities needed in the production line,specifically conveyors,processing equipments,robots,buffers.Finally,we have established a simulation layout model using the components in the customized library according to the block layout,and configured the components which were allocated in the layout by setting the parameters and building the connection between components via signal.To improve the performance of the workshop,we have found the best work-in-process(WIP)value for the workshop and the optimal number of workers.Additionally,the layout model was used to test collision and reachability.It demonstrated the production process in a realistic simulation environment which helped in the sales process as well.The reusable component models we have built make it easy to build a layout within a short time and validate the effectiveness of the layout scenarios for any other projects.展开更多
基金Supported by the Natural Science Foundation of Shandong Province(No.ZR 2023 MD 059)the National Natural Science Foundation of China(No.41876135)。
文摘Previous studies have revealed that ammonia nitrogen has several adverse effects on clam Ruditapes philippinarum.However,knowledge is lacking regarding the related proteins involved in the toxicological responses,which is vital to elucidate the underlying mechanism of ammonia nitrogen.In this study,clams R.philippinarum were exposed to ammonia nitrogen for 21 d at two environmentally relevant concentrations.The tandem mass tags approach(TMT)was applied to assay the differentially expressed proteins(DEPs)in clam gill tissues on the 3 rd and 21 st day.Finally,a total of 7263 proteins were identified.Bioinformatics analyses revealed that clam protein profiles changed in dose-and time dependent manner after ammonia nitrogen exposure.We inferred that the clams may face heavy challenges after ammonia exposure,such as unbalanced gender ratio,lysosomal disease,energy lack,neurological disorders,altered glutamine metabolism,increased lipid synthesis,and impaired immunity.Variation profiles of enzyme activities of glutaminase and glutamine synthase provided direct evidence to verify the related inference from proteome data.Most of the inferred toxic effects merit further study.This study identified important proteins related to ammonia nitrogen toxicity in the clam and indicated the severe stress of marine ammonia pollution on the healthy development of mollusc aquaculture.
基金funded by the National Natural Science Foundation of China-Liaoning Joint Fund(Grants:U20A20197)the National Natural Science Foundation of China(Grants:62173064)the Fundamental Research Funds for the Central Universities(Grants:N2326005).
文摘Autonomous navigation is a fundamental problem in robotics.Traditional methods generally build point cloud map or dense feature map in perceptual space;due to lack of cognition and memory formation mechanism,traditional methods exist poor robustness and low cognitive ability.As a new navigation technology that draws inspiration from mammal’s navigation,bionic navigation method can map perceptual information into cognitive space,and have strong autonomy and environment adaptability.To improve the robot’s autonomous navigation ability,this paper proposes a cognitive map-based hierarchical navigation method.First,the mammals’navigation-related grid cells and head direction cells are modeled to provide the robots with location cognition.And then a global path planning strategy based on cognitive map is proposed,which can anticipate one preferred global path to the target with high efficiency and short distance.Moreover,a hierarchical motion controlling method is proposed,with which the target navigation can be divided into several sub-target navigation,and the mobile robot can reach to these sub-targets with high confidence level.Finally,some experiments are implemented,the results show that the proposed path planning method can avoid passing through obstacles and obtain one preferred global path to the target with high efficiency,and the time cost does not increase extremely with the increase of experience nodes number.The motion controlling results show that the mobile robot can arrive at the target successfully only depending on its self-motion information,which is an effective attempt and reflects strong bionic properties.
基金National Natural Science Foundation of China(Grants:61873045)Fundamental Research Funds for the Central Universities in the Dalian University of Technology in China(Grant No.DUT20LAB303).
文摘Contact state estimation is significant for evaluating grasp stability of bionic hands,especially in unknown environments or without visual/tactile feedback.It still remains challenging,particularly for soft bionic hands without integrating complicated external sensors on soft fingers.Focusing on this issue,a proprioceptive-sensing-based systematic solution is proposed to estimate the contact state of soft bionic fingers in a single grasp.A kinematic model for soft fingers is first developed to capture the joint rotation angles and tendon displacement.A kinetostatic model is further built to estimate the contact force when soft fingers come in contact with objects.On this basis,a system stiffness model for soft fingers during preshaping and initial contact with objects is proposed to perceive the contact state.Moreover,an instantaneous stiffness model for soft fingers when initial contact occurs is developed for estimating the contact position on certain phalanges,especially the contact position along the distal phalange.The proposed proprioceptive-sensing-based approach is the first application in soft fingers without integrating complicated external sensors,which makes them concise and practical.Experiments are carried out to demonstrate the effectiveness and efficiency of our proposal.
文摘This paper proposes an uncalibrated workpiece positioning method for peg-in-hole assembly of a device using an industrial robot.Depth images are used to identify and locate the workpieces when a peg-in-hole assembly task is carried out by an industrial robot in a flexible production system.First,the depth image is thresholded according to the depth data of the workpiece surface so as to filter out the background interference.Second,a series of image processing and the feature recognition algorithms are executed to extract the outer contour features and locate the center point position.This image information,fed by the vision system,will drive the robot to achieve the positioning,approximately.Finally,the Hough circle detection algorithm is used to extract the features and the relevant parameters of the circular hole where the assembly would be done,on the color image,for accurate positioning.The experimental result shows that the positioning accuracy of this method is between 0.6-1.2 mm,in the used experimental system.The entire positioning process need not require complicated calibration,and the method is highly flexible.It is suitable for the automatic assembly tasks with multi-specification or in small batches,in a flexible production system.
基金supported by the National Key R&D Program of China(2023YFA1406200)the National Science Foundation of China(12174144 and 12304014)+2 种基金the Jilin Provincial Science&Technology Development Program(20220101002JC)the Graduate Innovation Fund of Jilin University(2024CX201)the Fundamental Research Funds for the Central Universities.
文摘The interaction between organic and inorganic components in metal hybrid perovskites fundamentally determines the intrinsic optoelectronic performance.However,the underlying interaction sites have still remained elusive,especially for those non-hydrogen-bonded hybrid perovskites,thus largely impeding materials precise design with targeted properties.Herein,high pressure is utilized to elucidate the interaction mechanism between organic and inorganic components in the as-synthesized one-dimensional hybrid metal halide(DBU)PbBr_(3)(DBU=1,8-diazabicyclo[5.4.0]undec-7-ene).The interaction sites are identified to be the N from DBU and the Br from inorganic framework by the indicative of enhanced Raman mode under high pressure.The change in interaction strength is indeed derived from the pressure modulation on both distance and spatial arrangement of the nearest Br and N,rather than traditional hydrogen-bonding effect.Furthermore,the enhanced interaction increased charge transfer,resulting in a cyan emission with photoluminescence quantum yields(PLQYs)of 86.6%.The enhanced cyan emission is particularly important for underwater communication due to the much less attenuation in water than at other wavelength emissions.This study provides deep insights into the underlying photophysical mechanism of non-hydrogen-bonded hybrid metal halides and is expected to impart innovative construction with superior performance.
基金This work was supported by the National Natural Science Foundation of China(Grant Nos.51705063 and 51575078)the Natural Science Foundation of Jiangsu Province,China(Grant No.BK20190368).
文摘A redundantly actuated parallel manipulator(RAPM)with mixed translational and rotational degrees of freedom(DOFs)is challenged for its dimensionally homogeneous Jacobian modeling and optimal design of architecture.In this paper,a means to achieve redundant actuation by adding kinematic constraints is introduced,which reduces the DOFs of the end-effector(EE).A generic dimensionally homogeneous Jacobian is developed for this type of RAPMs,which maps the generalized velocities of three points on the EE to the joint velocities.A new optimization algorithm derived from this dimension-ally homogeneous Jacobian is proposed for the optimal design of this type of RAPMs.As an example,this paper presents a spatial RAPM involving linkages and cam mechanisms.This RAPM has 4 DOFs and 6 translational actuations.The linkage lengths and the position of the universal joints of the RAPM are optimized based on the dimensionally homogeneous Jacobian.
基金supported by the Natural Science Foundation of Jiangsu Province,China(Grant No.BK20190368)the National Natural Science Foundation of China(Grant No.51705063)the Fundamental Research Funds for the Central Universities,and Zhishan Scholar Program of Southeast University,China.The authors declare no conflictofinterest.
文摘Masticatory robots are an effective in vitro performance testing device for dental material and mandibular prostheses.A cable-driven linear actuator(CDLA)capable of bidirectional motion is proposed in this study to design a masticatory robot that can achieve increasingly human-like chewing motion.The CDLA presents remarkable advantages,such as lightweight and high stiffness structure,in using cable amplification and pulley systems.This work also exploits the proposed CDLA and designs a masticatory robot called Southeast University masticatory robot(SMAR)to solve existing problems,such as bulky driving linkage and position change of the muscle’s origin.Stiffness analysis and performance experiment validate the CDLA’s efficiency,with its stiffness reaching 1379.6 N/mm(number of cable parts n=4),which is 21.4 times the input wire stiffness.Accordingly,the CDLA’s force transmission efficiencies in two directions are 84.5%and 85.9%.Chewing experiments are carried out on the developed masticatory robot to verify whether the CDLA can help SMAR achieve a natural human-like chewing motion and sufficient chewing forces for potential applications in performance tests of dental materials or prostheses.
基金the Provincial Key Technology Research and Innovation Program(3001-042097)for financial support,technician Liu Huan in the affiliation of VisualComponents for giving guidance on the software,technician Yuan Xiaoming in Yingkou Jinchen Machinery Co.,Ltd.for model simplification,and Sitara Aziz for spelling and grammar check.
文摘Facility layout problem(FLP)contemplates the optimization of space utilization,costs,and material flow.Commercial simulation softwares are commonly used to validate layouts by simulating the real world material flow and production process.To validate a layout scenario of a solar module assembly workshop,a 3D simulation model is presented which was designed on VisualComponents software.To begin with,we introduce the layout characteristics and use the systematic layout planning(SLP)method to design the block layout of workshop.Then,we built components library which contains all the facilities needed in the production line,specifically conveyors,processing equipments,robots,buffers.Finally,we have established a simulation layout model using the components in the customized library according to the block layout,and configured the components which were allocated in the layout by setting the parameters and building the connection between components via signal.To improve the performance of the workshop,we have found the best work-in-process(WIP)value for the workshop and the optimal number of workers.Additionally,the layout model was used to test collision and reachability.It demonstrated the production process in a realistic simulation environment which helped in the sales process as well.The reusable component models we have built make it easy to build a layout within a short time and validate the effectiveness of the layout scenarios for any other projects.
