The agricultural production space,as where and how much each agricultural product grows,plays a vital role in meeting the increasing and diverse food demands.Previous studies on agricultural production patterns have p...The agricultural production space,as where and how much each agricultural product grows,plays a vital role in meeting the increasing and diverse food demands.Previous studies on agricultural production patterns have predominantly centered on individual or specific crop types,using methods such as remote sensing or statistical metrological analysis.In this study,we characterize the agricultural production space(APS)by bipartite network connecting agricultural products and provinces,to reveal the relatedness between diverse agricultural products and the spatiotemporal characteristic of provincial production capabilities in China.The results show that core products are cereal,pork,melon,and pome fruit;meanwhile the milk,grape,and fiber crop show an upward trend in centrality,which is in line with diet structure changes in China over the past decades.The little changes in community components and structures of agricultural products and provinces reveal that agricultural production patterns in China are relatively stable.Additionally,identified provincial communities closely resemble China's agricultural natural zones.Furthermore,the observed growth in production capabilities in North and Northeast China implies their potential focus areas for future agricultural production.Despite the superior production capa-bilities of southern provinces,recent years have witnessed a notable decline,warranting special attentions.The findings provide a comprehensive perspective for understanding the complex relationship of agricultural prod-ucts'relatedness,production capabilities and production patterns,which serve as a reference for the agricultural spatial optimization and agricultural sustainable development.展开更多
Based on the characteristics of high-end products,crowd-sourcing user stories can be seen as an effective means of gathering requirements,involving a large user base and generating a substantial amount of unstructured...Based on the characteristics of high-end products,crowd-sourcing user stories can be seen as an effective means of gathering requirements,involving a large user base and generating a substantial amount of unstructured feedback.The key challenge lies in transforming abstract user needs into specific ones,requiring integration and analysis.Therefore,we propose a topic mining-based approach to categorize,summarize,and rank product requirements from user stories.Specifically,after determining the number of story categories based on py LDAvis,we initially classify“I want to”phrases within user stories.Subsequently,classic topic models are applied to each category to generate their names,defining each post-classification user story category as a requirement.Furthermore,a weighted ranking function is devised to calculate the importance of each requirement.Finally,we validate the effectiveness and feasibility of the proposed method using 2966 crowd-sourced user stories related to smart home systems.展开更多
The COP9 signalosome and the regulatory lid of the 26S proteasome are both eight-subunit protein complexes which are present in most eukaryotes. There is a one-to-one relationship between the corresponding subunits of...The COP9 signalosome and the regulatory lid of the 26S proteasome are both eight-subunit protein complexes which are present in most eukaryotes. There is a one-to-one relationship between the corresponding subunits of the two protein complexes in terms of their size and amino acid sequences. Eight groups of subunits from the COP9 signalosome and the proteasome lid complex of different organisms are collected from all the databases at the NCBI website. The corresponding subunits of COP9 signalosome and proteasome lid complex share at least 12% amino acid identity and some conserved regions, and the conserved sites spread evenly over the entire length of the subunits, suggesting that the two complexes have a common evolutionary ancestor. Phylogenetic analyses based on the amino acid sequences of the corresponding subunits of two protein complexes indicate that every tree consists of two clades. The subunits from one of the two protein complexes of different organisms are grouped into one of the two clades respectively. The sequences of single-cell organisms are always the basal groups to that of multi-cell animal and plant species. These results imply that the duplication/divergence events of COP9 signalosome and regulatory lid of the proteasome genes have occurred before the divergence of single-cell and multi-cell eukaryotes, and the genes of the two complexes are independently evolved. The analyses of dN/dS correlation show significant Pearson's correlations between 21 and 15 pairs of subunit-encoding sequences within the COP9 signalosome and the proteasome lid complex respectively, suggesting that those subunits pairs might have related functions and interacted with one another, and resulted in co-evolution.展开更多
Let (M1, F1) and (M2, F2) be two strongly pseudoconvex complex Finsler man- ifolds. The doubly wraped product complex Finsler manifold (f2 M1 x h M2, F) of (M1, F1) and (M2, F2) is the product manifold M1 x ...Let (M1, F1) and (M2, F2) be two strongly pseudoconvex complex Finsler man- ifolds. The doubly wraped product complex Finsler manifold (f2 M1 x h M2, F) of (M1, F1) and (M2, F2) is the product manifold M1 x M2 endowed with the warped product complex 2 2 Finsler metric F2 = f2F1 + fl F2, where fl and f2 are positive smooth functions on M1 and M2, respectively. In this paper, the most often used complex Finsler connections, holomorphic curvature, Ricci scalar curvature, and real geodesics of the DWP-complex Finsler manifold are derived in terms of the corresponding objects of its components. Necessary and sufficient conditions for the DWP-complex Finsler manifold to be K/ihler Finsler (resp., weakly K/ihler Finsler, complex Berwald, weakly complex Berwald, complex Landsberg) manifold are ob- tained, respectively. It is proved that if (M1, F1) and (M2,F2) are projectively flat, then the DWP-complex Finsler manifold is projectively flat if and only if fl and f2 are positive constants.展开更多
Let (M, F ) be the product complex Finsler manifold of two strongly pseudoconvex complex Finsler manifolds (M 1 , F 1 ) and (M 2 , F 2 ). In this paper, we obtain the relationship between the Chern Finsler conne...Let (M, F ) be the product complex Finsler manifold of two strongly pseudoconvex complex Finsler manifolds (M 1 , F 1 ) and (M 2 , F 2 ). In this paper, we obtain the relationship between the Chern Finsler connection coefficients Γ i ; k associated to F and the Chern Finsler connection coefficients Γ a ; c , Γα ; γ associated to F 1 , F 2 , respectively. As applications we prove that, if both (M 1 , F 1 ) and (M 2 , F 2 ) are strongly Ka¨hler Finsler (complex Berwald, or locally complex Minkowski, respectively) manifolds, so does (M, F ). Furthermore, we prove that the holomorphic curvature K F = 0 if and only if K F1 = 0 and K F2 = 0.展开更多
Minimizing the impact of the mixed uncertainties(i.e.,the aleatory uncertainty and the epistemic uncertainty) for a complex product of compliant mechanism(CPCM) quality improvement signifies a fascinating research top...Minimizing the impact of the mixed uncertainties(i.e.,the aleatory uncertainty and the epistemic uncertainty) for a complex product of compliant mechanism(CPCM) quality improvement signifies a fascinating research topic to enhance the robustness.However, most of the existing works in the CPCM robust design optimization neglect the mixed uncertainties, which might result in an unstable design or even an infeasible design. To solve this issue, a response surface methodology-based hybrid robust design optimization(RSM-based HRDO) approach is proposed to improve the robustness of the quality characteristic for the CPCM via considering the mixed uncertainties in the robust design optimization. A bridge-type amplification mechanism is used to manifest the effectiveness of the proposed approach. The comparison results prove that the proposed approach can not only keep its superiority in the robustness, but also provide a robust scheme for optimizing the design parameters.展开更多
In the conceptual design stage of complex products, CBR(Case-Based Reasoning) tool is useful to offer a feasible set of schemes. Then the most adaptive scheme can be generated through a procedure of comparison and e...In the conceptual design stage of complex products, CBR(Case-Based Reasoning) tool is useful to offer a feasible set of schemes. Then the most adaptive scheme can be generated through a procedure of comparison and evaluation. The procedure is essentially a multiple criteria decision-making problem. The traditional multiple criteria programming is not flexible enough in executing the system evaluation algorithm due to both the limited experimental data and the lack of human experiences. To make the CBR tool to be more efficient, a new method for the best choice among the feasible schemes based on the Fuzzy AHP using Fuzzy numbers (FFAHP) is proposed. Since the final results become a problem of ranking the mean of fuzzy numbers by the optimism of decision-maker using the FFAHP, its execution is much more intuitive and effective than with the traditional method.展开更多
This paper puts forward a complex inner product averaging method for calculating normal form of ODE. Compared with conventional averaging method, the theoretic analytical process has such simple forms as to realize co...This paper puts forward a complex inner product averaging method for calculating normal form of ODE. Compared with conventional averaging method, the theoretic analytical process has such simple forms as to realize computer program easily. Results can be applied in both autonomous and non-autonomous systems. At last, an example is resolved to verify the method.展开更多
Innovation design for complex products is a difficult issue in the military manufacturing industry. Ontology may provide a feasible way to rebuild the design process for complex products via sharing and reusing of des...Innovation design for complex products is a difficult issue in the military manufacturing industry. Ontology may provide a feasible way to rebuild the design process for complex products via sharing and reusing of design knowledge. In this paper, a design method used in the innovation design process of the complex products with knowledge modeling is proposed. Knowledge modeling is realized through ontology construction by combining the cycling evolutional theory of constructing ontology and OWL (Ontology Web Language)-based knowledge representation. As a case study, the satellite is selected as one of the complex products. The application domain of the satellite ontology is analyzed. According to the analysis result, the knowledge structure of satellite ontology is put forward based on OWL. The application of satellite product design shows that the method can effectively organize and reuse the knowledge resources in the innovation design of complex product and help companies to create more competitive products based on the existing knowledge and experience.展开更多
With the development of science and technology as well as the diversification and individualization of market demand,modern products update more and more rapidly.e rapid development of new products to satisfy the incr...With the development of science and technology as well as the diversification and individualization of market demand,modern products update more and more rapidly.e rapid development of new products to satisfy the increasingly improved and personalized customer demands greatly depends on the progress in the innovative design theory and performance optimization展开更多
Based on the comparison of several methods of time series predicting, this paper points out that it is necessary to use dynamic neural network in modeling of complex production process. Because self feedback and mutua...Based on the comparison of several methods of time series predicting, this paper points out that it is necessary to use dynamic neural network in modeling of complex production process. Because self feedback and mutual feedback are adopted among nodes at the same layer in Elman network, it has stronger ability of dynamic approximation, and can describe any non linear dynamic system. After the structure and mathematical description being given, dynamic back propagation (BP) algorithm of training weights of Elman neural network is deduced. At last, the network is used to predict ash content of black amber in jigging production process. The results show that this neural network is powerful in predicting and suitable for modeling, predicting, and controling of complex production process.展开更多
Background Augmented assembly guidance aims to help users complete assembly operations more efficiently and quickly through augmented reality technology,breaking the limitations of traditional assembly guidance techno...Background Augmented assembly guidance aims to help users complete assembly operations more efficiently and quickly through augmented reality technology,breaking the limitations of traditional assembly guidance technology which is single in content and boring in way.Object registration is one of the key technologies in augmented assembly guidance process,which can affect the location and direction of virtual assembly guidance information in real assembly environment.Methods This paper presents an object registration method based on RGB-D camera,which combines Lucas-Kanade(LK)optical flow algorithm and Iterative Closet Point(ICP)algorithm.An augmented assembly guidance system for complex products through this method is built.Meanwhile,in order to compare the effectiveness of the proposed method,we also implemented object registration based on an open source augmented reality SDK Vuforia.Results An engine model and a complex weapon cabin equipment are taken as an case to verify this work.The result shows that the registration method proposed in this paper is more accurate and stable compared with that based on Vuforia and the augmented assembly guidance system through this method greatly improves the user's time compared with the traditional assembly.Conclusions Therefore,we can conclude that the object registration method mentioned in this paper can be well applied in the augmented assembly guidance system,which can do enhance the efficiency of assembly considerably.展开更多
Simulation technique is an efficient approach to realize the planning and scheduling of manufacturing process of products. An appropriate and efficient manufacturing process model is the basis and key of manufacturing...Simulation technique is an efficient approach to realize the planning and scheduling of manufacturing process of products. An appropriate and efficient manufacturing process model is the basis and key of manufacturing process simulation. By analyzing the features of large-sized and complex products, a method of manufacturing process modeling based on activity network is presented and a mapping algorithm of translating BOM/BOP into the manufacturing process model is designed in detail.展开更多
Many catalysts were pcrpared by carbonization of ion exchange resin-PdCl_2 complexes at high temperature in nitrogen, hydrogen atmosphere. The rates for the hydrogenation of methyl acrylate and the amounts of Pd eluti...Many catalysts were pcrpared by carbonization of ion exchange resin-PdCl_2 complexes at high temperature in nitrogen, hydrogen atmosphere. The rates for the hydrogenation of methyl acrylate and the amounts of Pd elution of the carbonaceous products were measured and compared with those of commercial Pd/C catalyst. It indicates that the carbonaceous products are less active than Pd/C. However, the leaching of Pd from carbonaceous products is very small and much less than that from Pd/C.展开更多
基金supported by the Institute of Atmospheric Environment,China Meteorological Administration,Shenyang(Grant No.2021SYIAEKFMS27)Key Laboratory of Farm Building in Structure and Construction,Ministry of Agriculture and Rural Affairs,P.R.China(Grant No.202003)the National Foundation of China Scholarship Council(Grant No.202206040102).
文摘The agricultural production space,as where and how much each agricultural product grows,plays a vital role in meeting the increasing and diverse food demands.Previous studies on agricultural production patterns have predominantly centered on individual or specific crop types,using methods such as remote sensing or statistical metrological analysis.In this study,we characterize the agricultural production space(APS)by bipartite network connecting agricultural products and provinces,to reveal the relatedness between diverse agricultural products and the spatiotemporal characteristic of provincial production capabilities in China.The results show that core products are cereal,pork,melon,and pome fruit;meanwhile the milk,grape,and fiber crop show an upward trend in centrality,which is in line with diet structure changes in China over the past decades.The little changes in community components and structures of agricultural products and provinces reveal that agricultural production patterns in China are relatively stable.Additionally,identified provincial communities closely resemble China's agricultural natural zones.Furthermore,the observed growth in production capabilities in North and Northeast China implies their potential focus areas for future agricultural production.Despite the superior production capa-bilities of southern provinces,recent years have witnessed a notable decline,warranting special attentions.The findings provide a comprehensive perspective for understanding the complex relationship of agricultural prod-ucts'relatedness,production capabilities and production patterns,which serve as a reference for the agricultural spatial optimization and agricultural sustainable development.
基金supported by the National Natural Science Foundation of China(71690233,71901214)。
文摘Based on the characteristics of high-end products,crowd-sourcing user stories can be seen as an effective means of gathering requirements,involving a large user base and generating a substantial amount of unstructured feedback.The key challenge lies in transforming abstract user needs into specific ones,requiring integration and analysis.Therefore,we propose a topic mining-based approach to categorize,summarize,and rank product requirements from user stories.Specifically,after determining the number of story categories based on py LDAvis,we initially classify“I want to”phrases within user stories.Subsequently,classic topic models are applied to each category to generate their names,defining each post-classification user story category as a requirement.Furthermore,a weighted ranking function is devised to calculate the importance of each requirement.Finally,we validate the effectiveness and feasibility of the proposed method using 2966 crowd-sourced user stories related to smart home systems.
文摘The COP9 signalosome and the regulatory lid of the 26S proteasome are both eight-subunit protein complexes which are present in most eukaryotes. There is a one-to-one relationship between the corresponding subunits of the two protein complexes in terms of their size and amino acid sequences. Eight groups of subunits from the COP9 signalosome and the proteasome lid complex of different organisms are collected from all the databases at the NCBI website. The corresponding subunits of COP9 signalosome and proteasome lid complex share at least 12% amino acid identity and some conserved regions, and the conserved sites spread evenly over the entire length of the subunits, suggesting that the two complexes have a common evolutionary ancestor. Phylogenetic analyses based on the amino acid sequences of the corresponding subunits of two protein complexes indicate that every tree consists of two clades. The subunits from one of the two protein complexes of different organisms are grouped into one of the two clades respectively. The sequences of single-cell organisms are always the basal groups to that of multi-cell animal and plant species. These results imply that the duplication/divergence events of COP9 signalosome and regulatory lid of the proteasome genes have occurred before the divergence of single-cell and multi-cell eukaryotes, and the genes of the two complexes are independently evolved. The analyses of dN/dS correlation show significant Pearson's correlations between 21 and 15 pairs of subunit-encoding sequences within the COP9 signalosome and the proteasome lid complex respectively, suggesting that those subunits pairs might have related functions and interacted with one another, and resulted in co-evolution.
基金supported by Program for New Century Excellent Talents in University(NCET-13-0510)National Natural Science Foundation of China(11271304,11571288,11461064)+1 种基金the Fujian Province Natural Science Funds for Distinguished Young Scholar(2013J06001)the Scientific Research Foundation for the Returned Overseas Chinese Scholars,State Education Ministry
文摘Let (M1, F1) and (M2, F2) be two strongly pseudoconvex complex Finsler man- ifolds. The doubly wraped product complex Finsler manifold (f2 M1 x h M2, F) of (M1, F1) and (M2, F2) is the product manifold M1 x M2 endowed with the warped product complex 2 2 Finsler metric F2 = f2F1 + fl F2, where fl and f2 are positive smooth functions on M1 and M2, respectively. In this paper, the most often used complex Finsler connections, holomorphic curvature, Ricci scalar curvature, and real geodesics of the DWP-complex Finsler manifold are derived in terms of the corresponding objects of its components. Necessary and sufficient conditions for the DWP-complex Finsler manifold to be K/ihler Finsler (resp., weakly K/ihler Finsler, complex Berwald, weakly complex Berwald, complex Landsberg) manifold are ob- tained, respectively. It is proved that if (M1, F1) and (M2,F2) are projectively flat, then the DWP-complex Finsler manifold is projectively flat if and only if fl and f2 are positive constants.
基金supported by Program for New Century Excellent Talents in Fujian Provincial Universitythe Natural Science Foundation of China (10971170 10601040)
文摘Let (M, F ) be the product complex Finsler manifold of two strongly pseudoconvex complex Finsler manifolds (M 1 , F 1 ) and (M 2 , F 2 ). In this paper, we obtain the relationship between the Chern Finsler connection coefficients Γ i ; k associated to F and the Chern Finsler connection coefficients Γ a ; c , Γα ; γ associated to F 1 , F 2 , respectively. As applications we prove that, if both (M 1 , F 1 ) and (M 2 , F 2 ) are strongly Ka¨hler Finsler (complex Berwald, or locally complex Minkowski, respectively) manifolds, so does (M, F ). Furthermore, we prove that the holomorphic curvature K F = 0 if and only if K F1 = 0 and K F2 = 0.
基金supported by the National Natural Science Foundation of China(71702072 71811540414+2 种基金 71573115)the Natural Science Foundation for Jiangsu Institutions(BK20170810)the Ministry of Education of Humanities and Social Science Planning Fund(18YJA630008)
文摘Minimizing the impact of the mixed uncertainties(i.e.,the aleatory uncertainty and the epistemic uncertainty) for a complex product of compliant mechanism(CPCM) quality improvement signifies a fascinating research topic to enhance the robustness.However, most of the existing works in the CPCM robust design optimization neglect the mixed uncertainties, which might result in an unstable design or even an infeasible design. To solve this issue, a response surface methodology-based hybrid robust design optimization(RSM-based HRDO) approach is proposed to improve the robustness of the quality characteristic for the CPCM via considering the mixed uncertainties in the robust design optimization. A bridge-type amplification mechanism is used to manifest the effectiveness of the proposed approach. The comparison results prove that the proposed approach can not only keep its superiority in the robustness, but also provide a robust scheme for optimizing the design parameters.
基金This project was partly supported bythe Key Programof the National Natural Science Foundation of China (79990580) .
文摘In the conceptual design stage of complex products, CBR(Case-Based Reasoning) tool is useful to offer a feasible set of schemes. Then the most adaptive scheme can be generated through a procedure of comparison and evaluation. The procedure is essentially a multiple criteria decision-making problem. The traditional multiple criteria programming is not flexible enough in executing the system evaluation algorithm due to both the limited experimental data and the lack of human experiences. To make the CBR tool to be more efficient, a new method for the best choice among the feasible schemes based on the Fuzzy AHP using Fuzzy numbers (FFAHP) is proposed. Since the final results become a problem of ranking the mean of fuzzy numbers by the optimism of decision-maker using the FFAHP, its execution is much more intuitive and effective than with the traditional method.
文摘This paper puts forward a complex inner product averaging method for calculating normal form of ODE. Compared with conventional averaging method, the theoretic analytical process has such simple forms as to realize computer program easily. Results can be applied in both autonomous and non-autonomous systems. At last, an example is resolved to verify the method.
文摘Innovation design for complex products is a difficult issue in the military manufacturing industry. Ontology may provide a feasible way to rebuild the design process for complex products via sharing and reusing of design knowledge. In this paper, a design method used in the innovation design process of the complex products with knowledge modeling is proposed. Knowledge modeling is realized through ontology construction by combining the cycling evolutional theory of constructing ontology and OWL (Ontology Web Language)-based knowledge representation. As a case study, the satellite is selected as one of the complex products. The application domain of the satellite ontology is analyzed. According to the analysis result, the knowledge structure of satellite ontology is put forward based on OWL. The application of satellite product design shows that the method can effectively organize and reuse the knowledge resources in the innovation design of complex product and help companies to create more competitive products based on the existing knowledge and experience.
文摘With the development of science and technology as well as the diversification and individualization of market demand,modern products update more and more rapidly.e rapid development of new products to satisfy the increasingly improved and personalized customer demands greatly depends on the progress in the innovative design theory and performance optimization
文摘Based on the comparison of several methods of time series predicting, this paper points out that it is necessary to use dynamic neural network in modeling of complex production process. Because self feedback and mutual feedback are adopted among nodes at the same layer in Elman network, it has stronger ability of dynamic approximation, and can describe any non linear dynamic system. After the structure and mathematical description being given, dynamic back propagation (BP) algorithm of training weights of Elman neural network is deduced. At last, the network is used to predict ash content of black amber in jigging production process. The results show that this neural network is powerful in predicting and suitable for modeling, predicting, and controling of complex production process.
基金the National Defense Basic Scientific Research,China(JCKY2016605B006)National Defense Basic Scientific Research,China(JCKY2017203B071).
文摘Background Augmented assembly guidance aims to help users complete assembly operations more efficiently and quickly through augmented reality technology,breaking the limitations of traditional assembly guidance technology which is single in content and boring in way.Object registration is one of the key technologies in augmented assembly guidance process,which can affect the location and direction of virtual assembly guidance information in real assembly environment.Methods This paper presents an object registration method based on RGB-D camera,which combines Lucas-Kanade(LK)optical flow algorithm and Iterative Closet Point(ICP)algorithm.An augmented assembly guidance system for complex products through this method is built.Meanwhile,in order to compare the effectiveness of the proposed method,we also implemented object registration based on an open source augmented reality SDK Vuforia.Results An engine model and a complex weapon cabin equipment are taken as an case to verify this work.The result shows that the registration method proposed in this paper is more accurate and stable compared with that based on Vuforia and the augmented assembly guidance system through this method greatly improves the user's time compared with the traditional assembly.Conclusions Therefore,we can conclude that the object registration method mentioned in this paper can be well applied in the augmented assembly guidance system,which can do enhance the efficiency of assembly considerably.
文摘Simulation technique is an efficient approach to realize the planning and scheduling of manufacturing process of products. An appropriate and efficient manufacturing process model is the basis and key of manufacturing process simulation. By analyzing the features of large-sized and complex products, a method of manufacturing process modeling based on activity network is presented and a mapping algorithm of translating BOM/BOP into the manufacturing process model is designed in detail.
文摘Many catalysts were pcrpared by carbonization of ion exchange resin-PdCl_2 complexes at high temperature in nitrogen, hydrogen atmosphere. The rates for the hydrogenation of methyl acrylate and the amounts of Pd elution of the carbonaceous products were measured and compared with those of commercial Pd/C catalyst. It indicates that the carbonaceous products are less active than Pd/C. However, the leaching of Pd from carbonaceous products is very small and much less than that from Pd/C.