Toxoplasma gondii is a single-celled parasite that infects nearly all warm-blooded animals,including humans(Montoya and Liesenfeld,2004).It occurs worldwide and can persist for a lifetime in mammals.Humans get infecte...Toxoplasma gondii is a single-celled parasite that infects nearly all warm-blooded animals,including humans(Montoya and Liesenfeld,2004).It occurs worldwide and can persist for a lifetime in mammals.Humans get infected by eating undercooked meat of animals containing the tissue cysts of this parasite.In immune-competent individuals,T.展开更多
Analyzing the function of gene sets is a critical step in interpreting the results of high-throughput experiments in systems biology. A variety of enrichment analysis tools have been developed in recent years, but mos...Analyzing the function of gene sets is a critical step in interpreting the results of high-throughput experiments in systems biology. A variety of enrichment analysis tools have been developed in recent years, but most output a long list of significantly enriched terms that are often redundant, making it difficult to extract the most meaningful functions. In this paper, we present GOMA, a novel enrichment analysis method based on the new concept of enriched functional Gene Ontology (GO) modules. With this method, we systematically revealed functional GO modules, i.e., groups of functionally similar GO terms, via an optimization model and then ranked them by enrichment scores. Our new method simplifies enrichment analysis results by reducing redundancy, thereby preventing inconsistent enrichment results among functionally similar terms and providing more biologically meaningful results.展开更多
Dual redundant manipulators are extremely useful for tasks in dangerous or space environments, but efficient and real time coordinated control is hard to achieve. Collision avoidance between two cooperative manipulat...Dual redundant manipulators are extremely useful for tasks in dangerous or space environments, but efficient and real time coordinated control is hard to achieve. Collision avoidance between two cooperative manipulators is vital to the successful applications of dual redundant manipulators. Although methods based on the distance function have been demonstrated simple and efficient, different collision avoidance points can usually produce completely different results and even failure. The paper discussed the choices of collision avoidance points and proposed a novel method for the choosing of those points. The method is testified by simulation results of two redundant planar manipulators.展开更多
Reservoirs are an important water source in many densely populated areas in southwest China.Phytoplankton play an essential role in maintaining the structure and function of reservoir ecosystems.Understanding the succ...Reservoirs are an important water source in many densely populated areas in southwest China.Phytoplankton play an essential role in maintaining the structure and function of reservoir ecosystems.Understanding the succession in phytoplankton communities and the factors driving it are essential for eff ective water quality management in drinking water reservoirs.In this study,water samples were collected monthly at the surface layers from March 2016 to December 2019 in Hongfeng Reservoir,southwest China.The relationship between functional group succession was analyzed based on nonmetric multidimensional scaling analysis(NMDS),redundancy analysis(RDA),succession rate,and other analysis methods.The results showed distinct shifts in the community structure of phytoplankton functional groups within study period.The Cyclotella sp.was dominant in 2016 and 2017,and Pseudanabaena limnetica was the dominant group in 2018 and 2019.It appears that the phytoplankton composition and biomass are closely related to the water temperature and nutrient status in this reservoir.The results clearly showed that the permanganate index(COD_(Mn))was the key factor of dramatic phytoplankton functional group succession,and the change in succession rates was closely caused by total nitrogen concentration(TN).Therefore,the succession pattern and key factors of Hongfeng Reservoir revealed in this study were important guidance for the management of drinking water reservoirs in southwest China.A reasonable limit on exogenous nutrient input should be a priority,especially in high water temperature period.展开更多
Synapses are essential structures in the nervous system and normally form between two cells.However,some occur in a single neuron between the axon and its own dendrites and soma.These special synapses are known as aut...Synapses are essential structures in the nervous system and normally form between two cells.However,some occur in a single neuron between the axon and its own dendrites and soma.These special synapses are known as autapses(or autosynapses or self-synapses)[1].Previous studies have shown that autapses were much more abundant in cultured neurons[2–4]than in the intact brain,so there was suspicion that autapses in vivo may be wiring errors or redundant structures[5].展开更多
The study of macroscopic discrete granular materials holds significance in hydraulic engineering,geotechnical engineering,as well as road and bridge engineering.Its foundational scientific exploration bears profound t...The study of macroscopic discrete granular materials holds significance in hydraulic engineering,geotechnical engineering,as well as road and bridge engineering.Its foundational scientific exploration bears profound theoretical implications and is of pivotal practical value to engineering endeavors.Within the realm of engineering construction,issues such as dam breakages,earth-rock dam damage,and geological disasters involving loose particles pose substantial threats to the safety of both national livelihoods and property.Thus,delving into the examination of the structural stability of granular materials at the mesoscopic scale becomes an imperative pursuit.In this study,the topological structure of granular materials is identified and segmented based on image processing techniques,and the relationship between the compressive capacity of polygonal structures and the number of polygonal sides is studied.The redundancy function is defined to evaluate the structural stability of granular materials.In addition,the definition of structure tensor is introduced,and redundancy and structure tensor are applied to the study of biaxial compression of shale materials.The research results contribute to improving engineering safety and have guiding merits for the research and application of granular materials.Future work could focus on extending these methods to other types of granular materials and exploring their behavior under different loading conditions.展开更多
The kinematic redundancy in a robot leads to an infinite number of solutions for inverse kinematics,which implies the possibility to select a'best'solution according to an optimization criterion.In this paper,...The kinematic redundancy in a robot leads to an infinite number of solutions for inverse kinematics,which implies the possibility to select a'best'solution according to an optimization criterion.In this paper,two optimization objective functions are proposed,aiming at either minimizing extra degrees of freedom(DOFs)or minimizing the total potential energy of a multilink redundant robot.Physical constraints of either equality or inequality types are taken into consideration in the objective functions.Since the closed-form solutions do not exist in general for highly nonlinear and constrained optimization problems,we adopt and develop two numerical methods,which are verified to be effective and precise in solving the two optimization problems associated with the redundant inverse kinematics.We first verify that the well established trajectory following method can precisely solve the two optimization problems,but is computation intensive.To reduce the computation time,a sequential approach that combines the sequential quadratic programming and iterative Newton-Raphson algorithm is developed.A 4-DOF Fujitsu Hoap-1 humanoid robot arm is used as a prototype to validate the effectiveness of the proposed optimization solutions.展开更多
The 6-DOF manipulator provides a new option for traditional shipbuilding for its advantages of vast working space,low power consumption,and excellent flexibility.However,the rotation of the end effector along the tool...The 6-DOF manipulator provides a new option for traditional shipbuilding for its advantages of vast working space,low power consumption,and excellent flexibility.However,the rotation of the end effector along the tool axis is functionally redundant when using a robotic arm for five-axis machining.In the process of ship construction,the performance of the parts’protective coating needs to bemachined tomeet the Performance Standard of Protective Coatings(PSPC).The arbitrary redundancy configuration in path planning will result in drastic fluctuations in the robot joint angle,greatly reducing machining quality and efficiency.There have been some studies on singleobjective optimization of redundant variables,However,the quality and efficiency of milling are not affected by a single factor,it is usually influenced by several factors,such as the manipulator stiffness,the joint motion smoothness,and the energy consumption.To solve this problem,this paper proposed a new path optimization method for the industrial robot when it is used for five-axis machining.The path smoothness performance index and the energy consumption index are established based on the joint acceleration and the joint velocity,respectively.The path planning issue is formulated as a constrained multi-objective optimization problem by taking into account the constraints of joint limits and singularity avoidance.Then,the path is split into multiple segments for optimization to avoid the slow convergence rate caused by the high dimension.An algorithm combining the non-dominated sorting genetic algorithm(NSGA-II)and the differential evolution(DE)algorithm is employed to solve the above optimization problem.The simulations validate the effectiveness of the algorithm,showing the improvement of smoothness and the reduction of energy consumption.展开更多
Dempster-Shafer evidence theory, also called the theory of belief function, is widely used for uncertainty modeling and reasoning. However, when the size and number of focal elements are large, the evidence combinatio...Dempster-Shafer evidence theory, also called the theory of belief function, is widely used for uncertainty modeling and reasoning. However, when the size and number of focal elements are large, the evidence combination will bring a high computational complexity. To address this issue,various methods have been proposed including the implementation of more efficient combination rules and the simplifications or approximations of Basic Belief Assignments(BBAs). In this paper,a novel principle for approximating a BBA into a simpler one is proposed, which is based on the degree of non-redundancy for focal elements. More non-redundant focal elements are kept in the approximation while more redundant focal elements in the original BBA are removed first. Three types of degree of non-redundancy are defined based on three different definitions of focal element distance, respectively. Two different implementations of this principle for BBA approximations are proposed including a batch and an iterative type. Examples, experiments, comparisons and related analyses are provided to validate proposed approximation approaches.展开更多
Restoration ecology is a multidisciplinary science that exchanges several concepts with other scientific fields to improve its practices.In this article,I discuss the ecological redundancy concept and its implications...Restoration ecology is a multidisciplinary science that exchanges several concepts with other scientific fields to improve its practices.In this article,I discuss the ecological redundancy concept and its implications and applications on ecological restoration.Ecological redundancy was coined in the early 1990s to characterize those species that play similar(equivalent)functions in the ecosystem.The concept made it possible to segregate species into functional groups that operate in maintaining the system.I searched the literature and found that although some restoration models naturally consider this concept,studies in areas undergoing restoration which directly measure and test the ecological redundancy are still rare(n=14).I provide evidence that distinguishing redundant species and identifying key species is feasible for ecological restoration.Additionally,I suggest that redundancy should also be part of the restoration monitoring,for example,by checking if functional groups have been recovered.Theory predicts that if ecological redundancy is correctly incorporated in restoration,projects with more chances of success will be created because redundancy tends to increase ecosystem resilience.Resilience is a crucial factor for restoration sustainability in a changing environment.展开更多
基金supported by the National Natural Sci ence Foundation of China(No.31672543)the Zhejiang Province“Sannongliufang”Science and Technology Coopera tion Project(No.2020SNLF007),China.
文摘Toxoplasma gondii is a single-celled parasite that infects nearly all warm-blooded animals,including humans(Montoya and Liesenfeld,2004).It occurs worldwide and can persist for a lifetime in mammals.Humans get infected by eating undercooked meat of animals containing the tissue cysts of this parasite.In immune-competent individuals,T.
基金supported by grants from the National Natural Science Foundation of China(No.60970091, 61171007, 11131009)
文摘Analyzing the function of gene sets is a critical step in interpreting the results of high-throughput experiments in systems biology. A variety of enrichment analysis tools have been developed in recent years, but most output a long list of significantly enriched terms that are often redundant, making it difficult to extract the most meaningful functions. In this paper, we present GOMA, a novel enrichment analysis method based on the new concept of enriched functional Gene Ontology (GO) modules. With this method, we systematically revealed functional GO modules, i.e., groups of functionally similar GO terms, via an optimization model and then ranked them by enrichment scores. Our new method simplifies enrichment analysis results by reducing redundancy, thereby preventing inconsistent enrichment results among functionally similar terms and providing more biologically meaningful results.
文摘Dual redundant manipulators are extremely useful for tasks in dangerous or space environments, but efficient and real time coordinated control is hard to achieve. Collision avoidance between two cooperative manipulators is vital to the successful applications of dual redundant manipulators. Although methods based on the distance function have been demonstrated simple and efficient, different collision avoidance points can usually produce completely different results and even failure. The paper discussed the choices of collision avoidance points and proposed a novel method for the choosing of those points. The method is testified by simulation results of two redundant planar manipulators.
基金Supported by the National Natural Science Foundation of China(No.U1612442)the Science and Technology Foundation of Guizhou Province(Nos.[2020]6009,[2020]4Y009)Anton Brancelj was supported by Slovenian Research Agency(ARRS)(No.P1-0255)。
文摘Reservoirs are an important water source in many densely populated areas in southwest China.Phytoplankton play an essential role in maintaining the structure and function of reservoir ecosystems.Understanding the succession in phytoplankton communities and the factors driving it are essential for eff ective water quality management in drinking water reservoirs.In this study,water samples were collected monthly at the surface layers from March 2016 to December 2019 in Hongfeng Reservoir,southwest China.The relationship between functional group succession was analyzed based on nonmetric multidimensional scaling analysis(NMDS),redundancy analysis(RDA),succession rate,and other analysis methods.The results showed distinct shifts in the community structure of phytoplankton functional groups within study period.The Cyclotella sp.was dominant in 2016 and 2017,and Pseudanabaena limnetica was the dominant group in 2018 and 2019.It appears that the phytoplankton composition and biomass are closely related to the water temperature and nutrient status in this reservoir.The results clearly showed that the permanganate index(COD_(Mn))was the key factor of dramatic phytoplankton functional group succession,and the change in succession rates was closely caused by total nitrogen concentration(TN).Therefore,the succession pattern and key factors of Hongfeng Reservoir revealed in this study were important guidance for the management of drinking water reservoirs in southwest China.A reasonable limit on exogenous nutrient input should be a priority,especially in high water temperature period.
基金supported by the National Natural Science Foundation of China (31430038, 31630029, and 31661143037)
文摘Synapses are essential structures in the nervous system and normally form between two cells.However,some occur in a single neuron between the axon and its own dendrites and soma.These special synapses are known as autapses(or autosynapses or self-synapses)[1].Previous studies have shown that autapses were much more abundant in cultured neurons[2–4]than in the intact brain,so there was suspicion that autapses in vivo may be wiring errors or redundant structures[5].
基金supported by the Postdoctor Project of Hubei Province(2024HBBHCXA028)CRSRI Open Research Program(grant No.CKWV20241179/KY)+1 种基金Postdoctoral Fellowship Program of CPSF(grant No.GZC20230901)China Postdoctoral Science Foundation(grant No.2023M741267).
文摘The study of macroscopic discrete granular materials holds significance in hydraulic engineering,geotechnical engineering,as well as road and bridge engineering.Its foundational scientific exploration bears profound theoretical implications and is of pivotal practical value to engineering endeavors.Within the realm of engineering construction,issues such as dam breakages,earth-rock dam damage,and geological disasters involving loose particles pose substantial threats to the safety of both national livelihoods and property.Thus,delving into the examination of the structural stability of granular materials at the mesoscopic scale becomes an imperative pursuit.In this study,the topological structure of granular materials is identified and segmented based on image processing techniques,and the relationship between the compressive capacity of polygonal structures and the number of polygonal sides is studied.The redundancy function is defined to evaluate the structural stability of granular materials.In addition,the definition of structure tensor is introduced,and redundancy and structure tensor are applied to the study of biaxial compression of shale materials.The research results contribute to improving engineering safety and have guiding merits for the research and application of granular materials.Future work could focus on extending these methods to other types of granular materials and exploring their behavior under different loading conditions.
文摘The kinematic redundancy in a robot leads to an infinite number of solutions for inverse kinematics,which implies the possibility to select a'best'solution according to an optimization criterion.In this paper,two optimization objective functions are proposed,aiming at either minimizing extra degrees of freedom(DOFs)or minimizing the total potential energy of a multilink redundant robot.Physical constraints of either equality or inequality types are taken into consideration in the objective functions.Since the closed-form solutions do not exist in general for highly nonlinear and constrained optimization problems,we adopt and develop two numerical methods,which are verified to be effective and precise in solving the two optimization problems associated with the redundant inverse kinematics.We first verify that the well established trajectory following method can precisely solve the two optimization problems,but is computation intensive.To reduce the computation time,a sequential approach that combines the sequential quadratic programming and iterative Newton-Raphson algorithm is developed.A 4-DOF Fujitsu Hoap-1 humanoid robot arm is used as a prototype to validate the effectiveness of the proposed optimization solutions.
文摘The 6-DOF manipulator provides a new option for traditional shipbuilding for its advantages of vast working space,low power consumption,and excellent flexibility.However,the rotation of the end effector along the tool axis is functionally redundant when using a robotic arm for five-axis machining.In the process of ship construction,the performance of the parts’protective coating needs to bemachined tomeet the Performance Standard of Protective Coatings(PSPC).The arbitrary redundancy configuration in path planning will result in drastic fluctuations in the robot joint angle,greatly reducing machining quality and efficiency.There have been some studies on singleobjective optimization of redundant variables,However,the quality and efficiency of milling are not affected by a single factor,it is usually influenced by several factors,such as the manipulator stiffness,the joint motion smoothness,and the energy consumption.To solve this problem,this paper proposed a new path optimization method for the industrial robot when it is used for five-axis machining.The path smoothness performance index and the energy consumption index are established based on the joint acceleration and the joint velocity,respectively.The path planning issue is formulated as a constrained multi-objective optimization problem by taking into account the constraints of joint limits and singularity avoidance.Then,the path is split into multiple segments for optimization to avoid the slow convergence rate caused by the high dimension.An algorithm combining the non-dominated sorting genetic algorithm(NSGA-II)and the differential evolution(DE)algorithm is employed to solve the above optimization problem.The simulations validate the effectiveness of the algorithm,showing the improvement of smoothness and the reduction of energy consumption.
基金the National Natural Science Foundation of China (Nos. 61671370, 61573275)Postdoctoral Science Foundation of China (No. 2016M592790)+1 种基金Postdoctoral Science Research Foundation of Shaanxi Province, China (No. 2016BSHEDZZ46)Fundamental Research Funds for the Central Universities, China (No. xjj201066)
文摘Dempster-Shafer evidence theory, also called the theory of belief function, is widely used for uncertainty modeling and reasoning. However, when the size and number of focal elements are large, the evidence combination will bring a high computational complexity. To address this issue,various methods have been proposed including the implementation of more efficient combination rules and the simplifications or approximations of Basic Belief Assignments(BBAs). In this paper,a novel principle for approximating a BBA into a simpler one is proposed, which is based on the degree of non-redundancy for focal elements. More non-redundant focal elements are kept in the approximation while more redundant focal elements in the original BBA are removed first. Three types of degree of non-redundancy are defined based on three different definitions of focal element distance, respectively. Two different implementations of this principle for BBA approximations are proposed including a batch and an iterative type. Examples, experiments, comparisons and related analyses are provided to validate proposed approximation approaches.
文摘Restoration ecology is a multidisciplinary science that exchanges several concepts with other scientific fields to improve its practices.In this article,I discuss the ecological redundancy concept and its implications and applications on ecological restoration.Ecological redundancy was coined in the early 1990s to characterize those species that play similar(equivalent)functions in the ecosystem.The concept made it possible to segregate species into functional groups that operate in maintaining the system.I searched the literature and found that although some restoration models naturally consider this concept,studies in areas undergoing restoration which directly measure and test the ecological redundancy are still rare(n=14).I provide evidence that distinguishing redundant species and identifying key species is feasible for ecological restoration.Additionally,I suggest that redundancy should also be part of the restoration monitoring,for example,by checking if functional groups have been recovered.Theory predicts that if ecological redundancy is correctly incorporated in restoration,projects with more chances of success will be created because redundancy tends to increase ecosystem resilience.Resilience is a crucial factor for restoration sustainability in a changing environment.
