A large number of mathematical models were developed for supporting agricultural production structure optimization decisions; however, few of them can address various uncertainties existing in many factors (e.g., eco...A large number of mathematical models were developed for supporting agricultural production structure optimization decisions; however, few of them can address various uncertainties existing in many factors (e.g., eco-social benefit maximization, food security, employment stability and ecosystem balance). In this study, an interval-probabilistic agricultural production structure optimization model (IPAPSOM) is formulated for tackling uncertainty presented as discrete intervals and/or probability distribution. The developed model improves upon the existing probabilistic programming and inexact optimization approaches. The IPAPSOM considers not only food security policy constraints, but also involves rural households’income increase and eco-environmental conversation, which can effectively reflect various interrelations among different aspects in an agricultural production structure optimization system. Moreover, it can also help examine the reliability of satisfying (or risk of violating) system constraints under uncertainty. The model is applied to a real case of long-term agricultural production structure optimization in Dancheng County, which is located in Henan Province of Central China as one of the major grain producing areas. Interval solutions associated with different risk levels of constraint violation are obtained. The results are useful for generating a range of decision alternatives under various system benefit conditions, and thus helping decision makers to identify the desired agricultural production structure optimization strategy under uncertainty.展开更多
DEA is a nonparametric method used in operation researches and economics fields for the evaluation of the production frontier. It has distinct intrinsic which is worth coping with assessment problems with multiple inp...DEA is a nonparametric method used in operation researches and economics fields for the evaluation of the production frontier. It has distinct intrinsic which is worth coping with assessment problems with multiple inputs in particular with multiple outputs. This paper used D~ C2 R model of DEA to assess the comparative efficiency of the multiple schemes of agricultural industrial structure, at the end we chose the most favorable also known as "OPTIMAL" scheme. In addition to this, using some functional insights from DEA model non optimal schemes or less optimal schemes had also been improved to some extent. Assessment and selection of optimal schemes of agricultural industrial structure using DEA model gave a greater and better insight of agricultural industrial structure and was the first of such researches in Pakistan.展开更多
This paper used the modern evaluation method of DEA (Data Envelopment Analysis) to assess the comparative efficiency and then on the basis of this among multiple schemes chose the optimal scheme of agricultural prod...This paper used the modern evaluation method of DEA (Data Envelopment Analysis) to assess the comparative efficiency and then on the basis of this among multiple schemes chose the optimal scheme of agricultural production structure adjustment. Based on the results of DEA model, we dissected scale advantages of each discretionary scheme or plan. We examined scale advantages of each discretionary scheme, tested profoundly a definitive purpose behind not-DEA efficient, which elucidated the system and methodology to enhance these discretionary plans. At the end, another method had been proposed to rank and select the optimal scheme. The research was important to guide the practice if the modification of agricultural production industrial structure was carded on.展开更多
With the vigorous promotion of energy conservation and implementation of clean energy strategies,China's natural gas industry has entered a rapid development phase,and natural gas is playing an increasingly important...With the vigorous promotion of energy conservation and implementation of clean energy strategies,China's natural gas industry has entered a rapid development phase,and natural gas is playing an increasingly important role in China's energy structure.This paper uses a Generalized Weng model to forecast Chinese regional natural gas production,where accuracy and reasonableness compared with other predictions are enhanced by taking remaining estimated recoverable resources as a criterion.The forecast shows that China's natural gas production will maintain a rapid growth with peak gas of 323 billion cubic meters a year coming in 2036;in 2020,natural gas production will surpass that of oil to become a more important source of energy.Natural gas will play an important role in optimizing China's energy consumption structure and will be a strategic replacement of oil.This will require that exploration and development of conventional natural gas is highly valued and its industrial development to be reasonably planned.As well,full use should be made of domestic and international markets.Initiative should also be taken in the exploration and development of unconventional and deepwater gas,which shall form a complement to the development of China's conventional natural gas industry.展开更多
An enhanced system architecture of Web-based product structure and configuration management system along with its, functions are is presented. The key techniques, such as construction of object models of product str...An enhanced system architecture of Web-based product structure and configuration management system along with its, functions are is presented. The key techniques, such as construction of object models of product structure and product configuration, hybrid approach method in product configuration management, sharing and integration of heterogeneous product data, integration with other sub-systems, are discussed too. A prototype system is developed by J2EE technology.展开更多
Designed as a tool for business intelligence, resource planning is used to manage the essentials of a business by integrating processes into a single system. Enterprise Resource Planning (ERP) solutions ensure all the...Designed as a tool for business intelligence, resource planning is used to manage the essentials of a business by integrating processes into a single system. Enterprise Resource Planning (ERP) solutions ensure all the organizational, operational, and procedural structures interconnection, which can be both an advantage and a disadvantage, knowing that inefficiency within one structure will lead to inefficiency in others. The originality of the approach consists in the unitary analysis of all processes which shipbuilding involves (design;evaluation of ship construction possibilities;contracting of works;contracting of supply of materials and equipment;presentation of inspections for the completed works reception;delivery of the ship into operation). The systemic approach is a notable contribution by highlighting the input and output quantities for the analyzed processes. Also, where it was found relevant, the diagrams highlight the owners of the process and show the interconnectivity of the functional departments within a shipyard. Although it is obviously the expression of in-depth knowledge of the peculiarities of Romanian shipyards, the authors hope that the work can support any shipyard that may be interested in knowing these structures (as a logical scheme mandatory to design a custom ERP software system).展开更多
A three dimensional unison product with third derivative of displacement system of differential equations is presented. A projected plasma efavirenz concentration profile of a patient who had been on an orally adminis...A three dimensional unison product with third derivative of displacement system of differential equations is presented. A projected plasma efavirenz concentration profile of a patient who had been on an orally administered 600 mg daily dose of efavirenz is used as a structural aggregate. A three compartmental model of ordinary differential equations is suggested and solved numerically. The model projects descriptors associated with the product of a bounce that is a closed system. The product consists of three independent phases with two variable states, intenseness (concentration) that measures a structural aggregate and an environmental influence which is gravity. The third phase of the product is a processing function (spartial aggregate) which is a free potential. The function, a free potential, is responsible for ordering the product. A dynamical system with an attractive subspace which is an external potential (stable) with a zero eigenvalue is derived. The unison jerk’s Jacobian Matrix has corresponding negative, positive and zero eigenvalues.展开更多
Some key techniques for the development of web-based product data management (PDM) system are introduced. The four-tiered B/S architecture of a PDM system-BITPDM is introduced first, followed by its design and imple...Some key techniques for the development of web-based product data management (PDM) system are introduced. The four-tiered B/S architecture of a PDM system-BITPDM is introduced first, followed by its design and implementation, including virtual data vault, flexible coding system, document management, product structure and configuration management, workflow/process and product maturity management. BITPDM can facilitate the activities from new product introduction phase to manufacturing, and manage the product data andtheir dynamic changing history. Based on Microsoft. NET, XML, web service and SOAP techniques, BITPDM realizes the integration and efficient management of product information.展开更多
In this paper, the vertical and horizontal distributions of an invariant sub-manifold of a Riemannian product manifold are discussed. An invariant real space form in a Riemannian product manifold is researched. Finall...In this paper, the vertical and horizontal distributions of an invariant sub-manifold of a Riemannian product manifold are discussed. An invariant real space form in a Riemannian product manifold is researched. Finally, necessary and sufficient conditions are given on an invariant submanifold of a Riemannian product manifold to be a locally symmetric and real space form.展开更多
In this paper,we introduce the notion of a product structure on a 3-Bihom-Lie algebra,which is a Nijenhuis operator with some conditions.We prove that a 3-Bihom-Lie algebra has a product structure if and only if it is...In this paper,we introduce the notion of a product structure on a 3-Bihom-Lie algebra,which is a Nijenhuis operator with some conditions.We prove that a 3-Bihom-Lie algebra has a product structure if and only if it is the direct sum of two vector spaces which are also Bihom-subalgebras.Then we give four special conditions under each of which a 3-Bihom-Lie algebra has a special decomposition.Similarly,we introduce a complex structure on a 3-Bihom-Lie algebra and there are also four types of special complex structures.Finally,we establish the relation between a complex structure and a product structure.展开更多
According to the statistics of production and marketing data of major enterprises in 2021 by Surfac-tant Committee of China Cleaning Industry Association(CCIA),the development trend of main raw materials and products ...According to the statistics of production and marketing data of major enterprises in 2021 by Surfac-tant Committee of China Cleaning Industry Association(CCIA),the development trend of main raw materials and products of surfactant industry is analyzed in detail.The main trend development trend and characteristics of product structure is discussed under the influence of COVID-19,crude oil price fluctuation and economic structure adjustment.It pointed that the direction and planning of high-quality industry and the demand of new market in the 14th Five-Year.Product structure innovation and technological innovation is important.展开更多
The PLDIM (Product Lifecycle Dynamic Information Model) is the most important part of the PLDM (Product Lifecycle Dynamic Model ) and it is the basis to create the information system and to implement PLM (Product Life...The PLDIM (Product Lifecycle Dynamic Information Model) is the most important part of the PLDM (Product Lifecycle Dynamic Model ) and it is the basis to create the information system and to implement PLM (Product Lifecycle Management). The information classification, the relationships among all information items, PLDIM mathematic expression, information coding and the 3D synthetic description of the PLDIM are presented. The information flow and information system structure based on the two information centers and Internet/Intranet are proposed, and how to implement this system for ship diesel engines are also introduced according to the PLDIM and PLM solutions.展开更多
Along with the explosive increase of product data management systems (PDMs),integrating polymorphic PDMs is becoming one of the focuses in the field. Aner brief describing several features of PDM, and market requireme...Along with the explosive increase of product data management systems (PDMs),integrating polymorphic PDMs is becoming one of the focuses in the field. Aner brief describing several features of PDM, and market requirements and required performance for integrating the polymorphic PDMs, the paper specializes in discussing some key technologies involved in virtual enterprise oriented integrated development. Some implementing strategies and procedures are proposed.展开更多
Survivability strengthening/vulnerability reduction designs have become one of the most important design disciplines of military aircraft now. Due to progressiveness and complexity of modern combat aircraft, the exist...Survivability strengthening/vulnerability reduction designs have become one of the most important design disciplines of military aircraft now. Due to progressiveness and complexity of modern combat aircraft, the existing vulnerability modeling and computation methods cannot meet the current engineering application requirements. Therefore, a vulnerability modeling and computation method based on product structure and CATIA is proposed in sufficient consideration of the design characteristics of modern combat aircraft. This method directly constructs the aircraft vulnerability model by CATIA or the digital model database, and manages all the product components of the vulnerability model via aircraft product structure. Using CAA second development, the detailed operations and computation methods of vulnerability analysis are integrated into CATIA software environment. Comprehensive assessment data and visual kill probability Iso-contours can also be presented, which meet the vulnerability analysis requirements of modern combat aircraft effectively. The intact vulnerability model of one hypothetical aircraft is constructed, and the effects of redundant technology to the aircraft vulnerability are assessed, which validate the engineering practicality of the method.展开更多
In this work,we put forward a massively efficient filter for topology optimization(TO)utilizing the splitting of tensor product structure.With the aid of splitting technique,the traditional weight matrices of B-spline...In this work,we put forward a massively efficient filter for topology optimization(TO)utilizing the splitting of tensor product structure.With the aid of splitting technique,the traditional weight matrices of B-splines and non-uniform rational B-spline implicit filters are decomposed equivalently into two or three submatrices,by which the sensitivity analysis is reformulated for the nodal design variables without altering the optimization process.Afterwards,an explicit sensitivity filter,which is decomposed by the splitting pipeline as that applied to implicit filter,is established in terms of the tensor product of the axial distances between adjacent element centroids,and the corresponding sensitivity analysis is derived for elemental design variables.According to the numerical results,the average updating time for the design variables is accelerated by two-order-of-magnitude for the decomposed filter compared with the traditional filter.In addition,the memory burden and computing time of the weight matrix are decreased by six-and three-order-of-magnitude for the decomposed filter.Therefore,the proposed filter is massively improved by the splitting of tensor product structure and delivers a much more efficient way of solving TO problems in the frameworks of isogeometric analysis and finite element analysis.展开更多
In chemical product design,the aim is to formulate a product with desired performance.Ingredients and internal product structure are two key drivers of product performance with direct impact on the mechanical,electric...In chemical product design,the aim is to formulate a product with desired performance.Ingredients and internal product structure are two key drivers of product performance with direct impact on the mechanical,electrical,and thermal properties.Thus,there is a keen interest in elucidating the dependence of product performance on ingredients,structure,and the manufacturing process to form the structure.Design of product structure,particularly microstructure,is an intrinsically complex problem that involves different phases of different physicochemical properties,mass fraction,morphology,size distribution,and interconnectivity.Recently,computational methods have emerged that assist systematic microstructure quantification and prediction.The objective of this paper is to review these computational methods and to show how these methods as well as other developments in product design can work seamlessly in a proposed performance,ingredients,structure,and manufacturing process framework for the design of structured chemical products.It begins with the desired target properties and key ingredients.This is followed by computation for microstructure and then selection of processing steps to realize this microstructure.The framework is illustrated with the design of nanodielectric and die attach adhesive products.展开更多
Globally,the reduction of excessive N losses and greenhouse gas(GHG)emissions is a central environmental challenge in the 21 century.China has huge associated emissions during both production and land application phas...Globally,the reduction of excessive N losses and greenhouse gas(GHG)emissions is a central environmental challenge in the 21 century.China has huge associated emissions during both production and land application phases.In addition,70%of N fertilizer in China is produced and land applied as urea,which has high associated emissions.This study utilized life cycle analysis to compare the carbon emission capacity of different N fertilizers and quantified GHG emissions from different N fertilizer chains within China.This enabled a new innovative reform model to be proposed,which aims to decrease the carbon footprint and increase the net ecosystem carbon budget of China.The results showed that the carbon footprint of the N fertilizer industry was about 229 Tg·yr^(-1)CO_(2)-eq in 2020.Through changes away from urea through the production and land application of a mix of newly emerging fertilizers,liquid fertilizers and standard fertilizer reductions to 174–182 Tg·yr^(-1)CO_(2)-eq.Through the upgrading of mineral N fertilizer production technology,the carbon footprint of N fertilizer chain can be reduced by34.8 Tg·yr^(-1)CO_(2)-eq.Such reductions would reduce China's total GHG emissions to 140–147 Tg·yr^(-1)CO_(2)-eq.展开更多
Consider a discrete-time risk model with insurance and financial risks in a stochastic economic environment. Assume that the insurance and financial risks form a sequence of independent and identically distributed ran...Consider a discrete-time risk model with insurance and financial risks in a stochastic economic environment. Assume that the insurance and financial risks form a sequence of independent and identically distributed random vectors with a generic random vector following a wide type of dependence structure. An asymptotic formula for the finite-time ruin probability with subexponential insurance risks is derived. In doing so, the subexponentiality of the product of two dependent random variables is investigated simultaneously.展开更多
Abstract In this paper we investigate the quasi-shadowing property for C1 random dynamical sys-terns on their random partially hyperbolic sets. It is shown that for any pseudo orbit {xk}+∞ -∞ on a random partially ...Abstract In this paper we investigate the quasi-shadowing property for C1 random dynamical sys-terns on their random partially hyperbolic sets. It is shown that for any pseudo orbit {xk}+∞ -∞ on a random partially hyperbolic set there exists a "center" pseudo orbit {Yk}+∞ -∞ shadowing it in the sense that yk+l is obtained from the image of yk by a motion along the center direction. Moreover, when the random partially hyperbolic set has a local product structure, the above "center" pseudo orbit{yk}+∞ -∞ can be chosen such that yk+1 and the image of yk lie in their common center leaf.展开更多
An alternating mesophilic and thermophilic two stage anaerobic digestion (AD) process was conducted. The temperature of the acidogenic (A) and methanogenic (M) reactors was controlled as follows: System 1 (S1...An alternating mesophilic and thermophilic two stage anaerobic digestion (AD) process was conducted. The temperature of the acidogenic (A) and methanogenic (M) reactors was controlled as follows: System 1 (S1) mesophilic A-mesophilic M; (S2) mesophilic A-thermophilic M; and (S3) thermophilic A-mesophilic M. Initially, the AD reactor was acclimatized and inoculated with digester sludge. Food waste was added with the soluble chemical oxygen demand (SCOD) concentrations of 41.4-47.0 g/L and volatile fatty acids of 2.0-3.2 g/L. Based on the results, the highest total chemical oxygen demand removal (86.6%) was recorded in S2 while S3 exhibited the highest SCOD removal (96.6%). Comparing S1 with S2, total solids removal increased by 0.5%;S3 on the other hand decreased by 0.1% as compared to S1. However, volatile solids (VS) removal in S1, S2, and S3 was 78.5%, 81.7%, and 79.2%, respectively. S2 also exhibited the highest CH4 content, yield, and production rate of 70.7%, 0.44 L CH4/g VSadded, and 1.23 L CH4/(L.day), respectively. Bacterial community structure revealed that the richness, diversity, evenness, and dominance of S2 were high except for the archaeal community. The terminal restriction fragments dendrogram also revealed that the microbial community of the acidogenic and methanogenic reactors in S2 was distinct. Therefore, S2 was the best among the systems for the operation of two-stage AD of food waste in terms of CH4 production, nutrient removal, and microbial community structure.展开更多
基金funded by the National Natural Science Foundation of China (41130748, 41101162)the Key Knowledge Innovation Project of Chinese Academy of Sciences (KZCX2-EW-304)
文摘A large number of mathematical models were developed for supporting agricultural production structure optimization decisions; however, few of them can address various uncertainties existing in many factors (e.g., eco-social benefit maximization, food security, employment stability and ecosystem balance). In this study, an interval-probabilistic agricultural production structure optimization model (IPAPSOM) is formulated for tackling uncertainty presented as discrete intervals and/or probability distribution. The developed model improves upon the existing probabilistic programming and inexact optimization approaches. The IPAPSOM considers not only food security policy constraints, but also involves rural households’income increase and eco-environmental conversation, which can effectively reflect various interrelations among different aspects in an agricultural production structure optimization system. Moreover, it can also help examine the reliability of satisfying (or risk of violating) system constraints under uncertainty. The model is applied to a real case of long-term agricultural production structure optimization in Dancheng County, which is located in Henan Province of Central China as one of the major grain producing areas. Interval solutions associated with different risk levels of constraint violation are obtained. The results are useful for generating a range of decision alternatives under various system benefit conditions, and thus helping decision makers to identify the desired agricultural production structure optimization strategy under uncertainty.
文摘DEA is a nonparametric method used in operation researches and economics fields for the evaluation of the production frontier. It has distinct intrinsic which is worth coping with assessment problems with multiple inputs in particular with multiple outputs. This paper used D~ C2 R model of DEA to assess the comparative efficiency of the multiple schemes of agricultural industrial structure, at the end we chose the most favorable also known as "OPTIMAL" scheme. In addition to this, using some functional insights from DEA model non optimal schemes or less optimal schemes had also been improved to some extent. Assessment and selection of optimal schemes of agricultural industrial structure using DEA model gave a greater and better insight of agricultural industrial structure and was the first of such researches in Pakistan.
文摘This paper used the modern evaluation method of DEA (Data Envelopment Analysis) to assess the comparative efficiency and then on the basis of this among multiple schemes chose the optimal scheme of agricultural production structure adjustment. Based on the results of DEA model, we dissected scale advantages of each discretionary scheme or plan. We examined scale advantages of each discretionary scheme, tested profoundly a definitive purpose behind not-DEA efficient, which elucidated the system and methodology to enhance these discretionary plans. At the end, another method had been proposed to rank and select the optimal scheme. The research was important to guide the practice if the modification of agricultural production industrial structure was carded on.
基金the National Social Science Funds of China (13&ZD159)the National Natural Science Foundation of China (71303258, 71373285)+1 种基金MOE (Ministry of Education in China) Project of Humanities and Social Sciences (13YJC630148)Science Foundation of China University of Petroleum, Beijing (ZX20150130) for sponsoring this joint research
文摘With the vigorous promotion of energy conservation and implementation of clean energy strategies,China's natural gas industry has entered a rapid development phase,and natural gas is playing an increasingly important role in China's energy structure.This paper uses a Generalized Weng model to forecast Chinese regional natural gas production,where accuracy and reasonableness compared with other predictions are enhanced by taking remaining estimated recoverable resources as a criterion.The forecast shows that China's natural gas production will maintain a rapid growth with peak gas of 323 billion cubic meters a year coming in 2036;in 2020,natural gas production will surpass that of oil to become a more important source of energy.Natural gas will play an important role in optimizing China's energy consumption structure and will be a strategic replacement of oil.This will require that exploration and development of conventional natural gas is highly valued and its industrial development to be reasonably planned.As well,full use should be made of domestic and international markets.Initiative should also be taken in the exploration and development of unconventional and deepwater gas,which shall form a complement to the development of China's conventional natural gas industry.
基金Supported by the National High-Tech. R&D Program for CIMS China (Grant No. 2001AA412180)
文摘An enhanced system architecture of Web-based product structure and configuration management system along with its, functions are is presented. The key techniques, such as construction of object models of product structure and product configuration, hybrid approach method in product configuration management, sharing and integration of heterogeneous product data, integration with other sub-systems, are discussed too. A prototype system is developed by J2EE technology.
文摘Designed as a tool for business intelligence, resource planning is used to manage the essentials of a business by integrating processes into a single system. Enterprise Resource Planning (ERP) solutions ensure all the organizational, operational, and procedural structures interconnection, which can be both an advantage and a disadvantage, knowing that inefficiency within one structure will lead to inefficiency in others. The originality of the approach consists in the unitary analysis of all processes which shipbuilding involves (design;evaluation of ship construction possibilities;contracting of works;contracting of supply of materials and equipment;presentation of inspections for the completed works reception;delivery of the ship into operation). The systemic approach is a notable contribution by highlighting the input and output quantities for the analyzed processes. Also, where it was found relevant, the diagrams highlight the owners of the process and show the interconnectivity of the functional departments within a shipyard. Although it is obviously the expression of in-depth knowledge of the peculiarities of Romanian shipyards, the authors hope that the work can support any shipyard that may be interested in knowing these structures (as a logical scheme mandatory to design a custom ERP software system).
文摘A three dimensional unison product with third derivative of displacement system of differential equations is presented. A projected plasma efavirenz concentration profile of a patient who had been on an orally administered 600 mg daily dose of efavirenz is used as a structural aggregate. A three compartmental model of ordinary differential equations is suggested and solved numerically. The model projects descriptors associated with the product of a bounce that is a closed system. The product consists of three independent phases with two variable states, intenseness (concentration) that measures a structural aggregate and an environmental influence which is gravity. The third phase of the product is a processing function (spartial aggregate) which is a free potential. The function, a free potential, is responsible for ordering the product. A dynamical system with an attractive subspace which is an external potential (stable) with a zero eigenvalue is derived. The unison jerk’s Jacobian Matrix has corresponding negative, positive and zero eigenvalues.
文摘Some key techniques for the development of web-based product data management (PDM) system are introduced. The four-tiered B/S architecture of a PDM system-BITPDM is introduced first, followed by its design and implementation, including virtual data vault, flexible coding system, document management, product structure and configuration management, workflow/process and product maturity management. BITPDM can facilitate the activities from new product introduction phase to manufacturing, and manage the product data andtheir dynamic changing history. Based on Microsoft. NET, XML, web service and SOAP techniques, BITPDM realizes the integration and efficient management of product information.
文摘In this paper, the vertical and horizontal distributions of an invariant sub-manifold of a Riemannian product manifold are discussed. An invariant real space form in a Riemannian product manifold is researched. Finally, necessary and sufficient conditions are given on an invariant submanifold of a Riemannian product manifold to be a locally symmetric and real space form.
基金Supported by NNSF of China(No.12271085 and No.12071405)supported by Sichuan Science and Technology Program(No.2023NSFSC1287).
文摘In this paper,we introduce the notion of a product structure on a 3-Bihom-Lie algebra,which is a Nijenhuis operator with some conditions.We prove that a 3-Bihom-Lie algebra has a product structure if and only if it is the direct sum of two vector spaces which are also Bihom-subalgebras.Then we give four special conditions under each of which a 3-Bihom-Lie algebra has a special decomposition.Similarly,we introduce a complex structure on a 3-Bihom-Lie algebra and there are also four types of special complex structures.Finally,we establish the relation between a complex structure and a product structure.
文摘According to the statistics of production and marketing data of major enterprises in 2021 by Surfac-tant Committee of China Cleaning Industry Association(CCIA),the development trend of main raw materials and products of surfactant industry is analyzed in detail.The main trend development trend and characteristics of product structure is discussed under the influence of COVID-19,crude oil price fluctuation and economic structure adjustment.It pointed that the direction and planning of high-quality industry and the demand of new market in the 14th Five-Year.Product structure innovation and technological innovation is important.
文摘The PLDIM (Product Lifecycle Dynamic Information Model) is the most important part of the PLDM (Product Lifecycle Dynamic Model ) and it is the basis to create the information system and to implement PLM (Product Lifecycle Management). The information classification, the relationships among all information items, PLDIM mathematic expression, information coding and the 3D synthetic description of the PLDIM are presented. The information flow and information system structure based on the two information centers and Internet/Intranet are proposed, and how to implement this system for ship diesel engines are also introduced according to the PLDIM and PLM solutions.
文摘Along with the explosive increase of product data management systems (PDMs),integrating polymorphic PDMs is becoming one of the focuses in the field. Aner brief describing several features of PDM, and market requirements and required performance for integrating the polymorphic PDMs, the paper specializes in discussing some key technologies involved in virtual enterprise oriented integrated development. Some implementing strategies and procedures are proposed.
基金supported by National Natural Science Foundation of China (No. 11102159)
文摘Survivability strengthening/vulnerability reduction designs have become one of the most important design disciplines of military aircraft now. Due to progressiveness and complexity of modern combat aircraft, the existing vulnerability modeling and computation methods cannot meet the current engineering application requirements. Therefore, a vulnerability modeling and computation method based on product structure and CATIA is proposed in sufficient consideration of the design characteristics of modern combat aircraft. This method directly constructs the aircraft vulnerability model by CATIA or the digital model database, and manages all the product components of the vulnerability model via aircraft product structure. Using CAA second development, the detailed operations and computation methods of vulnerability analysis are integrated into CATIA software environment. Comprehensive assessment data and visual kill probability Iso-contours can also be presented, which meet the vulnerability analysis requirements of modern combat aircraft effectively. The intact vulnerability model of one hypothetical aircraft is constructed, and the effects of redundant technology to the aircraft vulnerability are assessed, which validate the engineering practicality of the method.
基金supported by the National Key R&D Program of China(Grant No.2020YFB1708300)China Postdoctoral Science Foundation(Grant No.2021M701310).
文摘In this work,we put forward a massively efficient filter for topology optimization(TO)utilizing the splitting of tensor product structure.With the aid of splitting technique,the traditional weight matrices of B-splines and non-uniform rational B-spline implicit filters are decomposed equivalently into two or three submatrices,by which the sensitivity analysis is reformulated for the nodal design variables without altering the optimization process.Afterwards,an explicit sensitivity filter,which is decomposed by the splitting pipeline as that applied to implicit filter,is established in terms of the tensor product of the axial distances between adjacent element centroids,and the corresponding sensitivity analysis is derived for elemental design variables.According to the numerical results,the average updating time for the design variables is accelerated by two-order-of-magnitude for the decomposed filter compared with the traditional filter.In addition,the memory burden and computing time of the weight matrix are decreased by six-and three-order-of-magnitude for the decomposed filter.Therefore,the proposed filter is massively improved by the splitting of tensor product structure and delivers a much more efficient way of solving TO problems in the frameworks of isogeometric analysis and finite element analysis.
文摘In chemical product design,the aim is to formulate a product with desired performance.Ingredients and internal product structure are two key drivers of product performance with direct impact on the mechanical,electrical,and thermal properties.Thus,there is a keen interest in elucidating the dependence of product performance on ingredients,structure,and the manufacturing process to form the structure.Design of product structure,particularly microstructure,is an intrinsically complex problem that involves different phases of different physicochemical properties,mass fraction,morphology,size distribution,and interconnectivity.Recently,computational methods have emerged that assist systematic microstructure quantification and prediction.The objective of this paper is to review these computational methods and to show how these methods as well as other developments in product design can work seamlessly in a proposed performance,ingredients,structure,and manufacturing process framework for the design of structured chemical products.It begins with the desired target properties and key ingredients.This is followed by computation for microstructure and then selection of processing steps to realize this microstructure.The framework is illustrated with the design of nanodielectric and die attach adhesive products.
基金supported by the“Green Intelligent Fertilizer Products”strategic research program funded by the CNSG Anhui Hong Sifang Co.,Ltd.Inhibitors Design and Development Project funded by the Wuwei Jincang Bioscience Co.,Ltd.Quzhou Agricultural Carbon Neutral Construction Project funded by the Quzhou Municipal Bureau of Agriculture and Rural Affairs。
文摘Globally,the reduction of excessive N losses and greenhouse gas(GHG)emissions is a central environmental challenge in the 21 century.China has huge associated emissions during both production and land application phases.In addition,70%of N fertilizer in China is produced and land applied as urea,which has high associated emissions.This study utilized life cycle analysis to compare the carbon emission capacity of different N fertilizers and quantified GHG emissions from different N fertilizer chains within China.This enabled a new innovative reform model to be proposed,which aims to decrease the carbon footprint and increase the net ecosystem carbon budget of China.The results showed that the carbon footprint of the N fertilizer industry was about 229 Tg·yr^(-1)CO_(2)-eq in 2020.Through changes away from urea through the production and land application of a mix of newly emerging fertilizers,liquid fertilizers and standard fertilizer reductions to 174–182 Tg·yr^(-1)CO_(2)-eq.Through the upgrading of mineral N fertilizer production technology,the carbon footprint of N fertilizer chain can be reduced by34.8 Tg·yr^(-1)CO_(2)-eq.Such reductions would reduce China's total GHG emissions to 140–147 Tg·yr^(-1)CO_(2)-eq.
基金Supported in part by the Natural National Science Foundation of China under Grant No.11671012the Natural Science Foundation of Anhui Province under Grant No.1808085MA16the Provincial Natural Science Research Project of Anhui Colleges under Grant No.KJ2017A024 and KJ2017A028
文摘Consider a discrete-time risk model with insurance and financial risks in a stochastic economic environment. Assume that the insurance and financial risks form a sequence of independent and identically distributed random vectors with a generic random vector following a wide type of dependence structure. An asymptotic formula for the finite-time ruin probability with subexponential insurance risks is derived. In doing so, the subexponentiality of the product of two dependent random variables is investigated simultaneously.
基金supported by NSFC(Grant Nos.11371120 and 11771118)supported by Fundamental Research Funds for the Central University,China(Grant No.20720170004)
文摘Abstract In this paper we investigate the quasi-shadowing property for C1 random dynamical sys-terns on their random partially hyperbolic sets. It is shown that for any pseudo orbit {xk}+∞ -∞ on a random partially hyperbolic set there exists a "center" pseudo orbit {Yk}+∞ -∞ shadowing it in the sense that yk+l is obtained from the image of yk by a motion along the center direction. Moreover, when the random partially hyperbolic set has a local product structure, the above "center" pseudo orbit{yk}+∞ -∞ can be chosen such that yk+1 and the image of yk lie in their common center leaf.
基金supported by the Korean Ministry of Agriculture, Food and Rural Affairs (313007-03-1-HD020)
文摘An alternating mesophilic and thermophilic two stage anaerobic digestion (AD) process was conducted. The temperature of the acidogenic (A) and methanogenic (M) reactors was controlled as follows: System 1 (S1) mesophilic A-mesophilic M; (S2) mesophilic A-thermophilic M; and (S3) thermophilic A-mesophilic M. Initially, the AD reactor was acclimatized and inoculated with digester sludge. Food waste was added with the soluble chemical oxygen demand (SCOD) concentrations of 41.4-47.0 g/L and volatile fatty acids of 2.0-3.2 g/L. Based on the results, the highest total chemical oxygen demand removal (86.6%) was recorded in S2 while S3 exhibited the highest SCOD removal (96.6%). Comparing S1 with S2, total solids removal increased by 0.5%;S3 on the other hand decreased by 0.1% as compared to S1. However, volatile solids (VS) removal in S1, S2, and S3 was 78.5%, 81.7%, and 79.2%, respectively. S2 also exhibited the highest CH4 content, yield, and production rate of 70.7%, 0.44 L CH4/g VSadded, and 1.23 L CH4/(L.day), respectively. Bacterial community structure revealed that the richness, diversity, evenness, and dominance of S2 were high except for the archaeal community. The terminal restriction fragments dendrogram also revealed that the microbial community of the acidogenic and methanogenic reactors in S2 was distinct. Therefore, S2 was the best among the systems for the operation of two-stage AD of food waste in terms of CH4 production, nutrient removal, and microbial community structure.