This study establishes the launch dynamics method,sensitivity analysis method,and multiobjective dynamic optimization method for the dynamic simulation analysis of the multiple launch rocket system(MLRS)based on the R...This study establishes the launch dynamics method,sensitivity analysis method,and multiobjective dynamic optimization method for the dynamic simulation analysis of the multiple launch rocket system(MLRS)based on the Riccati transfer matrix method for multibody systems(RMSTMM),direct differentiation method(DDM),and genetic algorithm(GA),respectively.Results show that simulation results of the dynamic response agree well with test results.The sensitivity analysis method is highly programming,the matrix order is low,and the calculation time is much shorter than that of the Lagrange method.With the increase of system complexity,the advantage of a high computing speed becomes more evident.Structural parameters that have the greatest influence on the dynamic response include the connection stiffness between the pitching body and the rotating body,the connection stiffness between the rotating body and the vehicle body,and the connection stiffnesses among 14^(#),16^(#),and 17^(#)wheels and the ground,which are the optimization design variables.After optimization,angular velocity variances of the pitching body in the revolving and pitching directions are reduced by 97.84%and 95.22%,respectively.展开更多
Since the birth of molecular evolutionary analysis, primates have been a central focus of study and mitochondrial DNA is well suited to these endeavors because of its unique features. Surprisingly, to date no comprehe...Since the birth of molecular evolutionary analysis, primates have been a central focus of study and mitochondrial DNA is well suited to these endeavors because of its unique features. Surprisingly, to date no comprehensive evaluation of the nucleotide substitution patterns has been conducted on the mitochondrial genome of primates. Here, we analyzed the evolutionary patterns and evaluated selection and recombination in the mitochondrial genomes of 44 Primates species downloaded from Genl3ank. The results revealed that a strong rate heterogeneity occurred among sites and genes in all comparisons. Likewise, an obvious decline in primate nucleotide diversity was noted in the subunit rRNAs and tRNAs as compared to the protein-coding genes. Within 13 protein-coding genes, the pattern of nonsynonymous divergence was similar to that of overall nucleotide divergence, while synonymous changes differed only for individual genes, indicating that the rate heterogeneity may result from the rate of change at nonsynonymous sites. Codon usage analysis revealed that there was intermediate codon usage bias in primate protein-coding genes, and supported the idea that GC mutation pressure might determine codon usage and that positive selection is not the driving force for the codon usage bias. Neutrality tests using site-specific positive selection from a Bayesian framework indicated no sites were under positive selection for any gene, consistent with near neutrality. Recombination tests based on the pairwise homoplasy test statistic supported complete linkage even for much older divergent primate species. Thus, with the exception of rate heterogeneity among mitochondrial genes, evaluating the validity assumed complete linkage and selective neutrality in primates prior to phylogenetic or phylogeographic analysis seems unnecessary.展开更多
Extramedullary hematopoiesis consists in the appearance and proliferation of hematopoietic cells outside the bone marrow. In this article, the authors describe a case of hepatosplenic hematopoiesis in a 9-year-old, ma...Extramedullary hematopoiesis consists in the appearance and proliferation of hematopoietic cells outside the bone marrow. In this article, the authors describe a case of hepatosplenic hematopoiesis in a 9-year-old, male Goeldi's monkey concurrent with a Calodium hepaticum infestation, belonging to the Lisbon's Zoo primate collection (Portugal). Lesions were identified upon necropsy after euthanasia due to the presence of an apparently non-excisable, metastatic aortic mass. Histopathological analysis of samples taken was carried out and immunohistochemical staining was used to characterize the cellular population involved, confirming the diagnosis of extramedullary hematopoiesis. To the best of the authors' knowledge, this is the first report of hepatosplenic extramedullary hematopoiesis in a Goeldi's monkey.展开更多
A reduced mechanism for propane/air combustion and its flame inhibition by phosphorus-containing compounds (PCCs) is constructed with the level of importance (LOI) method. The analysis is performed on solutions of fre...A reduced mechanism for propane/air combustion and its flame inhibition by phosphorus-containing compounds (PCCs) is constructed with the level of importance (LOI) method. The analysis is performed on solutions of freely propagating premixed flames with detailed chemical kinetics involving 121 species and 682 reactions proposed by Jayaweera et al. For the non-homogeneous reaction-diffusion system, the chemical lifetime of each species is weighted by its diffusion timescale, and the characteristic flame timescale is used to normalize the chemical lifetime. The definition of sensitivity in LOI is extended so that multi-parameters can be used as sensitivity targets. Propane, oxygen, dimethyl methylphosphonate (DMMP), and flame speed are selected to be perturbed for sensitivity analysis, the species with low LOI index are removed, and reactions involving the redundant species are excluded from the mechanism. A skeletal mechanism is obtained, which consists of 57 species and 268 elementary reactions. Calculations for laminar flame speeds, key flame radicals and catalytic cycles using the skeletal mechanism are in good agreement with those by using the detailed mechanism over a wide range of equivalence ratio undoped and doped with DMMP.展开更多
Chemically modified halloysite proved to be an effective adsorbent for the pesticide chlorpropham and 3-chloroaniline from an aqueous solution. Adsorption experiments were conducted using such procedures as the time-d...Chemically modified halloysite proved to be an effective adsorbent for the pesticide chlorpropham and 3-chloroaniline from an aqueous solution. Adsorption experiments were conducted using such procedures as the time-dependent (kinetic) procedure and the concentration dependent (isotherm) procedure. Results indicate that the adsorption process is related to the kind of the studied compound. The equilibrium data are well suited to a Freundlich isotherm in the case of both investigated compounds. Adsorption kinetics of chlorpropham and 3-chloroaniline on acid-treated halloysite was successfully described by pseudo-second order kinetic model and the model of Weber and Morris. From the present study, we suggest that the adsorption of chlorpropham and 3-chloroaniline on the modified halloysite is a rather complex process involving two steps: external mass transfer and intra-particle diffusion.展开更多
Aiming at the faults of some weak nodes in the concentrated solar power-photovoltaic(CSP-PV)hybrid power generation system,it is impossible to restore the transient voltage only relying on the reactive power regulatio...Aiming at the faults of some weak nodes in the concentrated solar power-photovoltaic(CSP-PV)hybrid power generation system,it is impossible to restore the transient voltage only relying on the reactive power regulation capability of the system itself.We propose a dynamic reactive power planning method suitable for CSP-PV hybrid power generation system.The method determines the installation node of the dynamic reactive power compensation device and its compensation capacity based on the reactive power adjustment capability of the system itself.The critical fault node is determined by the transient voltage stability recovery index,and the weak node of the system is initially determined.Based on this,the sensitivity index is used to determine the installation node of the dynamic reactive power compensation device.Dynamic reactive power planning optimization model is established with the lowest investment cost of dynamic reactive power compensation device and the improvement of system transient voltage stability.Furthermore,the component of the reactive power compensation node is optimized by particle swarm optimization based on differential evolution(DE-PSO).The simulation results of the example system show that compared with the dynamic position compensation device installation location optimization method,the proposed method can improve the transient voltage stability of the system under the same reactive power compensation cost.展开更多
Nonhuman culture was first considered in nonhuman primates because they are genetically similar to humans. How- ever, evolution is not progressive and therefore many species may occupy niches that favor socially trans...Nonhuman culture was first considered in nonhuman primates because they are genetically similar to humans. How- ever, evolution is not progressive and therefore many species may occupy niches that favor socially transmitted, group specific behavior. Not surprisingly, evidence for culture has accrued in several taxonomic groups, including cetaceans. If culture is an ada- ptation, it is imperative we understand the factors that favor its formation. Understanding the evolutionary origin of culture will allow for a wider range of species to be studied, including those that are difficult to test in the laboratory. I propose a broad-based functional paradigm for evaluating nonhuman culture; based on the idea that while not all cultural behaviors may garner fitness benefits to the individual, the ecological and social environments in which cultural behaviors evolved must have favored the physical attributes and social learning capabilities that allow for cultural formation. Specifically this framework emphasizes the relationships between social learning, ecology, social systems, and biology in relation to culture. I illustrate the utility of the func- tional paradigm with evidence from the ceteacean group, while setting the stage for a stringent species by species analysis. By means of contextualizing culture, the Functional Paradigm can evaluate a species' potential to exhibit culture and can investigate potentially cultural behaviors展开更多
基金The Natural Science Foundation of China(No.11972193)the Science Challenge Project(No.TZ2016006-0104)。
文摘This study establishes the launch dynamics method,sensitivity analysis method,and multiobjective dynamic optimization method for the dynamic simulation analysis of the multiple launch rocket system(MLRS)based on the Riccati transfer matrix method for multibody systems(RMSTMM),direct differentiation method(DDM),and genetic algorithm(GA),respectively.Results show that simulation results of the dynamic response agree well with test results.The sensitivity analysis method is highly programming,the matrix order is low,and the calculation time is much shorter than that of the Lagrange method.With the increase of system complexity,the advantage of a high computing speed becomes more evident.Structural parameters that have the greatest influence on the dynamic response include the connection stiffness between the pitching body and the rotating body,the connection stiffness between the rotating body and the vehicle body,and the connection stiffnesses among 14^(#),16^(#),and 17^(#)wheels and the ground,which are the optimization design variables.After optimization,angular velocity variances of the pitching body in the revolving and pitching directions are reduced by 97.84%and 95.22%,respectively.
基金This project was supported by the National Basic Research Program of China (973 Program:2007CB411600)the Natural Science Foundation of China (3063001630570292)
文摘Since the birth of molecular evolutionary analysis, primates have been a central focus of study and mitochondrial DNA is well suited to these endeavors because of its unique features. Surprisingly, to date no comprehensive evaluation of the nucleotide substitution patterns has been conducted on the mitochondrial genome of primates. Here, we analyzed the evolutionary patterns and evaluated selection and recombination in the mitochondrial genomes of 44 Primates species downloaded from Genl3ank. The results revealed that a strong rate heterogeneity occurred among sites and genes in all comparisons. Likewise, an obvious decline in primate nucleotide diversity was noted in the subunit rRNAs and tRNAs as compared to the protein-coding genes. Within 13 protein-coding genes, the pattern of nonsynonymous divergence was similar to that of overall nucleotide divergence, while synonymous changes differed only for individual genes, indicating that the rate heterogeneity may result from the rate of change at nonsynonymous sites. Codon usage analysis revealed that there was intermediate codon usage bias in primate protein-coding genes, and supported the idea that GC mutation pressure might determine codon usage and that positive selection is not the driving force for the codon usage bias. Neutrality tests using site-specific positive selection from a Bayesian framework indicated no sites were under positive selection for any gene, consistent with near neutrality. Recombination tests based on the pairwise homoplasy test statistic supported complete linkage even for much older divergent primate species. Thus, with the exception of rate heterogeneity among mitochondrial genes, evaluating the validity assumed complete linkage and selective neutrality in primates prior to phylogenetic or phylogeographic analysis seems unnecessary.
文摘Extramedullary hematopoiesis consists in the appearance and proliferation of hematopoietic cells outside the bone marrow. In this article, the authors describe a case of hepatosplenic hematopoiesis in a 9-year-old, male Goeldi's monkey concurrent with a Calodium hepaticum infestation, belonging to the Lisbon's Zoo primate collection (Portugal). Lesions were identified upon necropsy after euthanasia due to the presence of an apparently non-excisable, metastatic aortic mass. Histopathological analysis of samples taken was carried out and immunohistochemical staining was used to characterize the cellular population involved, confirming the diagnosis of extramedullary hematopoiesis. To the best of the authors' knowledge, this is the first report of hepatosplenic extramedullary hematopoiesis in a Goeldi's monkey.
基金Supported by the National Natural Science Foundation of China (50876097) the Program for New Century Excellent Talents in University of China (NCET-06-0546)
文摘A reduced mechanism for propane/air combustion and its flame inhibition by phosphorus-containing compounds (PCCs) is constructed with the level of importance (LOI) method. The analysis is performed on solutions of freely propagating premixed flames with detailed chemical kinetics involving 121 species and 682 reactions proposed by Jayaweera et al. For the non-homogeneous reaction-diffusion system, the chemical lifetime of each species is weighted by its diffusion timescale, and the characteristic flame timescale is used to normalize the chemical lifetime. The definition of sensitivity in LOI is extended so that multi-parameters can be used as sensitivity targets. Propane, oxygen, dimethyl methylphosphonate (DMMP), and flame speed are selected to be perturbed for sensitivity analysis, the species with low LOI index are removed, and reactions involving the redundant species are excluded from the mechanism. A skeletal mechanism is obtained, which consists of 57 species and 268 elementary reactions. Calculations for laminar flame speeds, key flame radicals and catalytic cycles using the skeletal mechanism are in good agreement with those by using the detailed mechanism over a wide range of equivalence ratio undoped and doped with DMMP.
文摘Chemically modified halloysite proved to be an effective adsorbent for the pesticide chlorpropham and 3-chloroaniline from an aqueous solution. Adsorption experiments were conducted using such procedures as the time-dependent (kinetic) procedure and the concentration dependent (isotherm) procedure. Results indicate that the adsorption process is related to the kind of the studied compound. The equilibrium data are well suited to a Freundlich isotherm in the case of both investigated compounds. Adsorption kinetics of chlorpropham and 3-chloroaniline on acid-treated halloysite was successfully described by pseudo-second order kinetic model and the model of Weber and Morris. From the present study, we suggest that the adsorption of chlorpropham and 3-chloroaniline on the modified halloysite is a rather complex process involving two steps: external mass transfer and intra-particle diffusion.
基金Science and Technology Projects of State Grid Corporation of China(No.SGGSKY00FJJS1800140)。
文摘Aiming at the faults of some weak nodes in the concentrated solar power-photovoltaic(CSP-PV)hybrid power generation system,it is impossible to restore the transient voltage only relying on the reactive power regulation capability of the system itself.We propose a dynamic reactive power planning method suitable for CSP-PV hybrid power generation system.The method determines the installation node of the dynamic reactive power compensation device and its compensation capacity based on the reactive power adjustment capability of the system itself.The critical fault node is determined by the transient voltage stability recovery index,and the weak node of the system is initially determined.Based on this,the sensitivity index is used to determine the installation node of the dynamic reactive power compensation device.Dynamic reactive power planning optimization model is established with the lowest investment cost of dynamic reactive power compensation device and the improvement of system transient voltage stability.Furthermore,the component of the reactive power compensation node is optimized by particle swarm optimization based on differential evolution(DE-PSO).The simulation results of the example system show that compared with the dynamic position compensation device installation location optimization method,the proposed method can improve the transient voltage stability of the system under the same reactive power compensation cost.
文摘Nonhuman culture was first considered in nonhuman primates because they are genetically similar to humans. How- ever, evolution is not progressive and therefore many species may occupy niches that favor socially transmitted, group specific behavior. Not surprisingly, evidence for culture has accrued in several taxonomic groups, including cetaceans. If culture is an ada- ptation, it is imperative we understand the factors that favor its formation. Understanding the evolutionary origin of culture will allow for a wider range of species to be studied, including those that are difficult to test in the laboratory. I propose a broad-based functional paradigm for evaluating nonhuman culture; based on the idea that while not all cultural behaviors may garner fitness benefits to the individual, the ecological and social environments in which cultural behaviors evolved must have favored the physical attributes and social learning capabilities that allow for cultural formation. Specifically this framework emphasizes the relationships between social learning, ecology, social systems, and biology in relation to culture. I illustrate the utility of the func- tional paradigm with evidence from the ceteacean group, while setting the stage for a stringent species by species analysis. By means of contextualizing culture, the Functional Paradigm can evaluate a species' potential to exhibit culture and can investigate potentially cultural behaviors