The production and energy coupling system is used to mainly present energy flow, material flow, information flow, and their coupling interaction. Through the modeling and simulation of this system, the performance of ...The production and energy coupling system is used to mainly present energy flow, material flow, information flow, and their coupling interaction. Through the modeling and simulation of this system, the performance of energy flow can be analyzed and optimized in the process industry. In order to study this system, the component based hybrid Petri net methodology (CpnHPN) is proposed, synthesizing a number of extended Petri net methods and using the concept of energy place, material place, and information place. Through the interface place in CpnHPN, the component based encapsulation is established, which enables the production and energy coupling system to be built, analyzed, and optimized on the multi-level framework. Considering the block and brief simulation for hybrid system, the CpnHPN model is simulated with Simulink/Stateflow. To illustrate the use of the proposed methodology, the application of CpnHPN in the energy optimization of chlorine balance system is provided.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
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
This paper proposes an approach of developing the feature based parametric product modeling system which is suitable for integrated engineering design in CIMS environment.The architecture of ZD--MCADII and the charact...This paper proposes an approach of developing the feature based parametric product modeling system which is suitable for integrated engineering design in CIMS environment.The architecture of ZD--MCADII and the characteristics of its each module are introduced in detail. ZD--MCADII’s product data is managed by an object--oriented database management system OSCAR, and the product model is built according to the standard STEP. The product design is established on a unified product model, and all the product data are globally associated in ZD--MCADII. ZD--MCADII provides various design features to facilitate the product design, and supports the integrity of CAD, CAPP and CAM.展开更多
This paper proposes a novel locally linear backpropagation based contribution(LLBBC) for nonlinear process fault diagnosis. As a method based on the deep learning model of auto-encoder(AE), LLBBC can deal with the fau...This paper proposes a novel locally linear backpropagation based contribution(LLBBC) for nonlinear process fault diagnosis. As a method based on the deep learning model of auto-encoder(AE), LLBBC can deal with the fault diagnosis problem through extracting nonlinear features. When the on-line fault diagnosis task is in progress, a locally linear model is firstly built at the current fault sample. According to the basic idea of reconstruction based contribution(RBC), the propagation of fault information is described by using back-propagation(BP) algorithm. Then, a contribution index is established to measure the correlation between the variable and the fault, and the final diagnosis result is obtained by searching variables with large contributions. The smearing effect, which is an important factor affecting the performance of fault diagnosis, can be suppressed as well,and the theoretical analysis reveals that the correct diagnosis can be guaranteed by LLBBC. Finally, the feasibility and effectiveness of the proposed method are verified through a nonlinear numerical example and the Tennessee Eastman benchmark process.展开更多
According to the characteristic of Team Software Process (TSP), it adopts a hierarchy-based model combined discrete event model with system dynamics model. This model represents TSP as form of two levels, the inner ...According to the characteristic of Team Software Process (TSP), it adopts a hierarchy-based model combined discrete event model with system dynamics model. This model represents TSP as form of two levels, the inner level embodies the continuity of the software process, the outer embodies the software development process by phases, and the structure and principle of the model is explained in detail, then formalization description of the model is offered. At last, an example is presented to demonstrate the simulation process and result. This model can simulate team software process from various angles, supervise and predict the software process. Also it can make the management of software development become more scientific and improve the quality of software.展开更多
Monitoring high-dimensional multistage processes becomes crucial to ensure the quality of the final product in modern industry environments. Few statistical process monitoring(SPC) approaches for monitoring and contro...Monitoring high-dimensional multistage processes becomes crucial to ensure the quality of the final product in modern industry environments. Few statistical process monitoring(SPC) approaches for monitoring and controlling quality in highdimensional multistage processes are studied. We propose a deviance residual-based multivariate exponentially weighted moving average(MEWMA) control chart with a variable selection procedure. We demonstrate that it outperforms the existing multivariate SPC charts in terms of out-of-control average run length(ARL) for the detection of process mean shift.展开更多
Aiming at the limitations of the existing knowledge representations in intelligent detection, a new method of Extension-based Knowledge Representation (EKR) was proposed. The definitions, grammar rules, and storage st...Aiming at the limitations of the existing knowledge representations in intelligent detection, a new method of Extension-based Knowledge Representation (EKR) was proposed. The definitions, grammar rules, and storage structure of EKR were presented. An Extension Solving Model (ESM) based on EKR was discussed in detail, including creation of the extension constraint graph, extended inference, calculation of relevant functions and generation of extension set. A knowledge base system based on EKR and ESM was developed, which was applied in extension repository system intelligent design of detection in photosynthesis process of D.huoshanense. More reasonable results were obtained than traditional rule-based system. EKR was feasible in intelligent design to solve the problem of intelligent detection knowledge representations.展开更多
Based on the data related to the Chinese and world agricultural production and trade from 1986 to 2011,this paper uses the principal component analysis,cointegration and vector error correction model to perform the em...Based on the data related to the Chinese and world agricultural production and trade from 1986 to 2011,this paper uses the principal component analysis,cointegration and vector error correction model to perform the empirical analysis of the impact of processing,import and export of agricultural products on the agricultural modernization in China. The results show that the processing and export of agricultural products play a role in promoting the agricultural modernization in China,while the import of agricultural products has some negative effects on the agricultural modernization in China. The negative effects of the import of agricultural products are from the limitations of farmers' small-scale operation and foreign trading partners' protectionism. China should further develop the processing industry of agricultural products,and strengthen the role of downstream industries in promoting the agricultural modernization; improve the level of large-scale and intensive operation,and make good use of WTO rules,in order to provide the necessary market conditions for the agricultural modernization.展开更多
Using Michael Porter's "diamond model", based on regional development characteristics, we conduct analysis of the competitiveness of processing industry cluster of livestock products in Inner Mongolia fr...Using Michael Porter's "diamond model", based on regional development characteristics, we conduct analysis of the competitiveness of processing industry cluster of livestock products in Inner Mongolia from six aspects (the factor conditions, demand conditions, corporate strategy, structure and competition, related and supporting industries, government and opportunities). And we put forward the following rational recommendations for improving the competitiveness of processing industry cluster of livestock products in Inner Mongolia: (i) The government should increase capital input, focus on supporting processing industry of livestock products, and give play to the guidance and aggregation effect of financial funds; (ii) In terms of enterprises, it is necessary to vigorously develop leading enterprises, to give full play to the cluster effect of the leading enterprises.展开更多
With regards to the assembly line of cost control of Dechang company,the motor housing′s cost control of process will be necessarily appreciated.Though the supply quantity is large in a machine and the price of motor...With regards to the assembly line of cost control of Dechang company,the motor housing′s cost control of process will be necessarily appreciated.Though the supply quantity is large in a machine and the price of motor housing is cheaper,the cost control of automatic production line is significant in this respection.It is found that insufficiency power is main cause for production line failure.The cost control of equipment includes to structure wheel,conveyor and motor for benefit which also needs to be controlled in detail.Only in this way can we fundamentally resolve the main problem of high cost process.When the capital price L increases,Avc also increases too with nonlinear meantime,and Tc&Vc increase in proportion to K.Among them,the Tc increases the highest and then Vc increases lightly.Generally when labour quantity L and capital quantity K increase cost increases in proportion.展开更多
The transition from middle-income to high-income stage is fraught with risks of growth divergence.Economic transition is clouded by the following possibilities:(1) falling share of industrial sector through industrial...The transition from middle-income to high-income stage is fraught with risks of growth divergence.Economic transition is clouded by the following possibilities:(1) falling share of industrial sector through industrial depression and weakening growth momentum caused by the large urbanization costs;(2) the subordination of service sector as a result of nearly irreversibly industrial professional,which falters the process of service sector transition and upgrading;(3) inefficient knowledge production allocation and human capital upgrade due to the absence of incentivized compensation of knowledge consumption.We suggest that a country should reshape its efficiency model by upgrading knowledge factor and human capital as the pre-requisite.Given the dilemmas of transition,China should take the factorization trend of service sector and reshape efficiency model through institutional reform,ensuring that service sector will develop in tandem with industrial sector.展开更多
Globally a large number of process-based models have been assessed for quantification of agricultural greenhouse gas (GHG) emissions. Modelling approaches minimize the presence of spatial variability of biogeochemical...Globally a large number of process-based models have been assessed for quantification of agricultural greenhouse gas (GHG) emissions. Modelling approaches minimize the presence of spatial variability of biogeochemical processes, leading to improved estimates of GHGs as well as identifying mitigation and policy options. The comparative performance of the three dynamic models (e.g., DNDC v9.4, DailyDayCent and ECOSSE v5+) with minimum numbers of common input parameters was evaluated against measured variables. Simulations were performed on conventionally-tilled spring barley crops receiving N fertilizer at 135 - 159 kg·N·ha<sup>-</sup><sup>1</sup>·yr<sup>-</sup><sup>1</sup> and crop residues at 3 t·ha<sup>-</sup><sup>1</sup>·yr<sup>-</sup><sup>1</sup>. For surface soil nitrate (0 - 10 cm), the ECOSSE and DNDC simulated values showed significant correlations with measured values (R<sup>2</sup> = 0.31 - 0.55, p 0.05). Only the ECOSSE-simulated N<sub>2</sub>O fluxes showed a significant relationship (R<sup>2</sup> = 0.33, p 0.05) with values measured from fertilized fields, but not with unfertilized ones. The DNDC and DailyDayCent models significantly underestimated seasonal/annual N<sub>2</sub>O fluxes compared to ECOSSE, with emission factors (EFs), based on an 8-year average, were 0.09%, 0.31% and 0.52%, respectively. Predictions of ecosystem respiration by both DailyDayCent and DNDC showed reasonable agreement with Eddy Covariance data (R<sup>2</sup> = 0.34 - 0.41, p 0.05). Compared to the measured value (3624 kg·C·ha<sup>-</sup><sup>1</sup>·yr<sup>-</sup><sup>1</sup>), the ECOSSE underestimated annual heterotrophic respiration by 7% but this was smaller than the DNDC (50%) and DailyDayCent (24%) estimates. All models simulated CH<sub>4</sub> uptake we展开更多
Small watersheds are the basic composition unit of the Loess Plateau in China. An accurate estimation of vegetation net primary productivity (NPP) is of great significance for eco-benefit evaluation in small watersh...Small watersheds are the basic composition unit of the Loess Plateau in China. An accurate estimation of vegetation net primary productivity (NPP) is of great significance for eco-benefit evaluation in small watershed management in this region. Here we describe the development and testing of a vegetation-producing process model (VPP) of a small watershed in the Loess Plateau. The model couples three modules: radiation adjustment; soil hydrological processes; and vegetation carbon assimilation. Model validation indicates that the VPP model can be used to estimate the NPP of small watersheds in the region. With the VPP model, we estimated the spatial NPP distributions in the Yangou watershed for 2007. The results show that in the Yangou watershed the NPP is relatively low, averaging 168 g C/(m^2.a). Trees and shrubs have a higher NPP than crops and grasses. The NPP is larger on the partly shaded and shaded slopes than on the partly sunny and sunny slopes. The NPP on the slopes increases gradually on 0-20° slopes and decreases slightly on slopes steeper than 20°. Our simulation indicates that the vegetation type is the most important factor in determining the NPP distribution in small watersheds in the Loess Plateau.展开更多
[Objectives]This study aimed to observe the effects of different processed products of Radix Codonopsis on intestinal flora in rats with spleen deficiency.[Methods]Rat models with spleen deficiency were established by...[Objectives]This study aimed to observe the effects of different processed products of Radix Codonopsis on intestinal flora in rats with spleen deficiency.[Methods]Rat models with spleen deficiency were established by bitter-cold purgation method with Radix et Rhizoma Rhei.Normal group,model group,Radix Codonopsis group,fried Radix Codonopsis group,rice-fried Radix Codonopsis group,honey-fried Radix Codonopsis group and bran-fired Radix Codonopsis group were designed.After subjecting to corresponding treatments,the changes in the quantity of intestinal microorganisms of the rats were detected.[Results]There was no significant change in the quantity of intestinal microorganisms of the rats in the normal group and model group.The rats in the rice-fried Radix Codonopsis group were administered after successful modeling,and the abundance of Bifidobacterium and Lactobacillus in the intestines of the rats increased,and the quantity of Escherichia coli and Staphylococci reduced.The rats in the Radix Codonopsis group,fried Radix Codonopsis groups,honey-fried Radix Codonopsis group and bran-fried Radix Codonopsis group were administered after successful modeling,and the abundance of Bifidobacterium and Lactobacillus in the intestines of the rats increased(the increases were smaller than those in the rice-fried Radix Codonopsis group),and the abundance of E.coli and Staphylococci reduced,close to normal levels.[Conclusions]Different processed products of Radix Codonopsis have obvious regulation effect on intestinal flora of rats with spleen deficiency,and the regulation effect of rice-fried Radix Codonopsis on rats with spleen deficiency is better than that of Radix Codonopsis,fried Radix Codonopsis,honey-fried Radix Codonopsis and bran-fried Radix Codonopsis.展开更多
In the course of network supported collaborative design, the data processing plays a very vital role. Much effort has been spent in this area, and many kinds of approaches have been proposed. Based on the correlative ...In the course of network supported collaborative design, the data processing plays a very vital role. Much effort has been spent in this area, and many kinds of approaches have been proposed. Based on the correlative materials, this paper presents extensible markup language (XML) based strategy for several important problems of data processing in network supported collaborative design, such as the representation of standard for the exchange of product model data (STEP) with XML in the product information expression and the management of XML documents using relational database. The paper gives a detailed exposition on how to clarify the mapping between XML structure and the relationship database structure and how XML-QL queries can be translated into structured query language (SQL) queries. Finally, the structure of data processing system based on XML is presented.展开更多
Arid and semiarid ecosystems, or dryland, are important to global biogeochemical cycles. Dryland's community structure and vegetation dynamics as well as biogeochemical cycles are sensitive to changes in climate and ...Arid and semiarid ecosystems, or dryland, are important to global biogeochemical cycles. Dryland's community structure and vegetation dynamics as well as biogeochemical cycles are sensitive to changes in climate and atmospheric composition. Vegetation dynamic models has been applied in global change studies, but the com- plex interactions among the carbon (C), water, and nitrogen (N) cycles have not been adequately addressed in the current models. In this study, a process-based vegetation dynamic model was developed to study the responses of dryland ecosystems to environmental changes, emphasizing on the interactions among the C, water, and N proc- esses. To address the interactions between the C and water processes, it not only considers the effects of annual precipitation on vegetation distribution and soil moisture on organic matter (SOM) decomposition, but also explicitly models root competition for water and the water compensation processes. To address the interactions between C and N processes, it models the soil inorganic mater processes, such as N mineralization/immobilization, denitrifica- tion/nitrification, and N leaching, as well as the root competition for soil N. The model was parameterized for major plant functional types and evaluated against field observations.展开更多
基金Shanghai Municipal Science & Technology Projects, China (No. 09DZ1203300, No. 10JC1415200)
文摘The production and energy coupling system is used to mainly present energy flow, material flow, information flow, and their coupling interaction. Through the modeling and simulation of this system, the performance of energy flow can be analyzed and optimized in the process industry. In order to study this system, the component based hybrid Petri net methodology (CpnHPN) is proposed, synthesizing a number of extended Petri net methods and using the concept of energy place, material place, and information place. Through the interface place in CpnHPN, the component based encapsulation is established, which enables the production and energy coupling system to be built, analyzed, and optimized on the multi-level framework. Considering the block and brief simulation for hybrid system, the CpnHPN model is simulated with Simulink/Stateflow. To illustrate the use of the proposed methodology, the application of CpnHPN in the energy optimization of chlorine balance system is provided.
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.
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This paper proposes an approach of developing the feature based parametric product modeling system which is suitable for integrated engineering design in CIMS environment.The architecture of ZD--MCADII and the characteristics of its each module are introduced in detail. ZD--MCADII’s product data is managed by an object--oriented database management system OSCAR, and the product model is built according to the standard STEP. The product design is established on a unified product model, and all the product data are globally associated in ZD--MCADII. ZD--MCADII provides various design features to facilitate the product design, and supports the integrity of CAD, CAPP and CAM.
基金supported by the Key Project of National Natural Science Foundation of China(61933013)Ningbo 13th Five-year Marine Economic Innovation and Development Demonstration Project(NBH Y-2017-Z1)。
文摘This paper proposes a novel locally linear backpropagation based contribution(LLBBC) for nonlinear process fault diagnosis. As a method based on the deep learning model of auto-encoder(AE), LLBBC can deal with the fault diagnosis problem through extracting nonlinear features. When the on-line fault diagnosis task is in progress, a locally linear model is firstly built at the current fault sample. According to the basic idea of reconstruction based contribution(RBC), the propagation of fault information is described by using back-propagation(BP) algorithm. Then, a contribution index is established to measure the correlation between the variable and the fault, and the final diagnosis result is obtained by searching variables with large contributions. The smearing effect, which is an important factor affecting the performance of fault diagnosis, can be suppressed as well,and the theoretical analysis reveals that the correct diagnosis can be guaranteed by LLBBC. Finally, the feasibility and effectiveness of the proposed method are verified through a nonlinear numerical example and the Tennessee Eastman benchmark process.
基金Supported by the National Defense Basic ResearchFoundation (K1503063165)
文摘According to the characteristic of Team Software Process (TSP), it adopts a hierarchy-based model combined discrete event model with system dynamics model. This model represents TSP as form of two levels, the inner level embodies the continuity of the software process, the outer embodies the software development process by phases, and the structure and principle of the model is explained in detail, then formalization description of the model is offered. At last, an example is presented to demonstrate the simulation process and result. This model can simulate team software process from various angles, supervise and predict the software process. Also it can make the management of software development become more scientific and improve the quality of software.
基金supported by the Qatar National Research Fund(NPRP5-364-2-142NPRP7-1040-2-293)
文摘Monitoring high-dimensional multistage processes becomes crucial to ensure the quality of the final product in modern industry environments. Few statistical process monitoring(SPC) approaches for monitoring and controlling quality in highdimensional multistage processes are studied. We propose a deviance residual-based multivariate exponentially weighted moving average(MEWMA) control chart with a variable selection procedure. We demonstrate that it outperforms the existing multivariate SPC charts in terms of out-of-control average run length(ARL) for the detection of process mean shift.
文摘Aiming at the limitations of the existing knowledge representations in intelligent detection, a new method of Extension-based Knowledge Representation (EKR) was proposed. The definitions, grammar rules, and storage structure of EKR were presented. An Extension Solving Model (ESM) based on EKR was discussed in detail, including creation of the extension constraint graph, extended inference, calculation of relevant functions and generation of extension set. A knowledge base system based on EKR and ESM was developed, which was applied in extension repository system intelligent design of detection in photosynthesis process of D.huoshanense. More reasonable results were obtained than traditional rule-based system. EKR was feasible in intelligent design to solve the problem of intelligent detection knowledge representations.
基金Supported by Business Management Discipline Cultivation Project of Rongchang Campus of Southwest University(RCQG207001)
文摘Based on the data related to the Chinese and world agricultural production and trade from 1986 to 2011,this paper uses the principal component analysis,cointegration and vector error correction model to perform the empirical analysis of the impact of processing,import and export of agricultural products on the agricultural modernization in China. The results show that the processing and export of agricultural products play a role in promoting the agricultural modernization in China,while the import of agricultural products has some negative effects on the agricultural modernization in China. The negative effects of the import of agricultural products are from the limitations of farmers' small-scale operation and foreign trading partners' protectionism. China should further develop the processing industry of agricultural products,and strengthen the role of downstream industries in promoting the agricultural modernization; improve the level of large-scale and intensive operation,and make good use of WTO rules,in order to provide the necessary market conditions for the agricultural modernization.
基金Supported by National Natural Science Foundation(70963014,71210107012)
文摘Using Michael Porter's "diamond model", based on regional development characteristics, we conduct analysis of the competitiveness of processing industry cluster of livestock products in Inner Mongolia from six aspects (the factor conditions, demand conditions, corporate strategy, structure and competition, related and supporting industries, government and opportunities). And we put forward the following rational recommendations for improving the competitiveness of processing industry cluster of livestock products in Inner Mongolia: (i) The government should increase capital input, focus on supporting processing industry of livestock products, and give play to the guidance and aggregation effect of financial funds; (ii) In terms of enterprises, it is necessary to vigorously develop leading enterprises, to give full play to the cluster effect of the leading enterprises.
文摘With regards to the assembly line of cost control of Dechang company,the motor housing′s cost control of process will be necessarily appreciated.Though the supply quantity is large in a machine and the price of motor housing is cheaper,the cost control of automatic production line is significant in this respection.It is found that insufficiency power is main cause for production line failure.The cost control of equipment includes to structure wheel,conveyor and motor for benefit which also needs to be controlled in detail.Only in this way can we fundamentally resolve the main problem of high cost process.When the capital price L increases,Avc also increases too with nonlinear meantime,and Tc&Vc increase in proportion to K.Among them,the Tc increases the highest and then Vc increases lightly.Generally when labour quantity L and capital quantity K increase cost increases in proportion.
基金sponsored by major tendering projects of National Social Sciences Foundation "Study on Accelerating Economic Adjustment and Coordinated Development"(Grant No.12&ZD084) and "Study on Contribution of Consumption to Economic Growth under Shifting Demand Structure"(Grant No.15ZDC011)projects of National Social Sciences Foundation "Study on China's Structural Growth Deceleration,Transition Risks and Efficiency Improvement Path"(Grant No.14AJL006) and "Study on the Scale,Spatial Clustering and Management Model of Chinese Cities"(Grant No.15ZDC011)
文摘The transition from middle-income to high-income stage is fraught with risks of growth divergence.Economic transition is clouded by the following possibilities:(1) falling share of industrial sector through industrial depression and weakening growth momentum caused by the large urbanization costs;(2) the subordination of service sector as a result of nearly irreversibly industrial professional,which falters the process of service sector transition and upgrading;(3) inefficient knowledge production allocation and human capital upgrade due to the absence of incentivized compensation of knowledge consumption.We suggest that a country should reshape its efficiency model by upgrading knowledge factor and human capital as the pre-requisite.Given the dilemmas of transition,China should take the factorization trend of service sector and reshape efficiency model through institutional reform,ensuring that service sector will develop in tandem with industrial sector.
文摘Globally a large number of process-based models have been assessed for quantification of agricultural greenhouse gas (GHG) emissions. Modelling approaches minimize the presence of spatial variability of biogeochemical processes, leading to improved estimates of GHGs as well as identifying mitigation and policy options. The comparative performance of the three dynamic models (e.g., DNDC v9.4, DailyDayCent and ECOSSE v5+) with minimum numbers of common input parameters was evaluated against measured variables. Simulations were performed on conventionally-tilled spring barley crops receiving N fertilizer at 135 - 159 kg·N·ha<sup>-</sup><sup>1</sup>·yr<sup>-</sup><sup>1</sup> and crop residues at 3 t·ha<sup>-</sup><sup>1</sup>·yr<sup>-</sup><sup>1</sup>. For surface soil nitrate (0 - 10 cm), the ECOSSE and DNDC simulated values showed significant correlations with measured values (R<sup>2</sup> = 0.31 - 0.55, p 0.05). Only the ECOSSE-simulated N<sub>2</sub>O fluxes showed a significant relationship (R<sup>2</sup> = 0.33, p 0.05) with values measured from fertilized fields, but not with unfertilized ones. The DNDC and DailyDayCent models significantly underestimated seasonal/annual N<sub>2</sub>O fluxes compared to ECOSSE, with emission factors (EFs), based on an 8-year average, were 0.09%, 0.31% and 0.52%, respectively. Predictions of ecosystem respiration by both DailyDayCent and DNDC showed reasonable agreement with Eddy Covariance data (R<sup>2</sup> = 0.34 - 0.41, p 0.05). Compared to the measured value (3624 kg·C·ha<sup>-</sup><sup>1</sup>·yr<sup>-</sup><sup>1</sup>), the ECOSSE underestimated annual heterotrophic respiration by 7% but this was smaller than the DNDC (50%) and DailyDayCent (24%) estimates. All models simulated CH<sub>4</sub> uptake we
基金financed by the Strategic Priority Research Program (XDA05050403)the Key Research Program of Chinese Academy of Sciences (KZZD-EW-04)
文摘Small watersheds are the basic composition unit of the Loess Plateau in China. An accurate estimation of vegetation net primary productivity (NPP) is of great significance for eco-benefit evaluation in small watershed management in this region. Here we describe the development and testing of a vegetation-producing process model (VPP) of a small watershed in the Loess Plateau. The model couples three modules: radiation adjustment; soil hydrological processes; and vegetation carbon assimilation. Model validation indicates that the VPP model can be used to estimate the NPP of small watersheds in the region. With the VPP model, we estimated the spatial NPP distributions in the Yangou watershed for 2007. The results show that in the Yangou watershed the NPP is relatively low, averaging 168 g C/(m^2.a). Trees and shrubs have a higher NPP than crops and grasses. The NPP is larger on the partly shaded and shaded slopes than on the partly sunny and sunny slopes. The NPP on the slopes increases gradually on 0-20° slopes and decreases slightly on slopes steeper than 20°. Our simulation indicates that the vegetation type is the most important factor in determining the NPP distribution in small watersheds in the Loess Plateau.
基金Supported by National Natural Science Foundation of China(No.81360524)Youth Foundation of Guangxi University of Chinese Medicine(No.2019QN036)+2 种基金Basic Ability Improvement Project for Scientific Research of Young and Middle-aged Teachers in Colleges and Universities of Guangxi(No.2019KY0341)Key Research and Development Project of Science and Technology Department of Guangxi(No.AB19110003)Third-class Chinese(Zhuang)Medicine Chemistry and Quality Analysis Laboratory of National Administration of Traditional Chinese Medicine(Guo Zhong Yi Yao Fa 2009[21]).
文摘[Objectives]This study aimed to observe the effects of different processed products of Radix Codonopsis on intestinal flora in rats with spleen deficiency.[Methods]Rat models with spleen deficiency were established by bitter-cold purgation method with Radix et Rhizoma Rhei.Normal group,model group,Radix Codonopsis group,fried Radix Codonopsis group,rice-fried Radix Codonopsis group,honey-fried Radix Codonopsis group and bran-fired Radix Codonopsis group were designed.After subjecting to corresponding treatments,the changes in the quantity of intestinal microorganisms of the rats were detected.[Results]There was no significant change in the quantity of intestinal microorganisms of the rats in the normal group and model group.The rats in the rice-fried Radix Codonopsis group were administered after successful modeling,and the abundance of Bifidobacterium and Lactobacillus in the intestines of the rats increased,and the quantity of Escherichia coli and Staphylococci reduced.The rats in the Radix Codonopsis group,fried Radix Codonopsis groups,honey-fried Radix Codonopsis group and bran-fried Radix Codonopsis group were administered after successful modeling,and the abundance of Bifidobacterium and Lactobacillus in the intestines of the rats increased(the increases were smaller than those in the rice-fried Radix Codonopsis group),and the abundance of E.coli and Staphylococci reduced,close to normal levels.[Conclusions]Different processed products of Radix Codonopsis have obvious regulation effect on intestinal flora of rats with spleen deficiency,and the regulation effect of rice-fried Radix Codonopsis on rats with spleen deficiency is better than that of Radix Codonopsis,fried Radix Codonopsis,honey-fried Radix Codonopsis and bran-fried Radix Codonopsis.
基金supported by National High Technology Research and Development Program of China (863 Program) (No. AA420060)
文摘In the course of network supported collaborative design, the data processing plays a very vital role. Much effort has been spent in this area, and many kinds of approaches have been proposed. Based on the correlative materials, this paper presents extensible markup language (XML) based strategy for several important problems of data processing in network supported collaborative design, such as the representation of standard for the exchange of product model data (STEP) with XML in the product information expression and the management of XML documents using relational database. The paper gives a detailed exposition on how to clarify the mapping between XML structure and the relationship database structure and how XML-QL queries can be translated into structured query language (SQL) queries. Finally, the structure of data processing system based on XML is presented.
基金supported by the International Science & Technology Cooperation Program of China (2010DFA92720-10)the "Hundred Talents Program" of the Chinese Academy of Sciences (Y174131001)supported by the National Basic Research Program of China (2009CB825105)
文摘Arid and semiarid ecosystems, or dryland, are important to global biogeochemical cycles. Dryland's community structure and vegetation dynamics as well as biogeochemical cycles are sensitive to changes in climate and atmospheric composition. Vegetation dynamic models has been applied in global change studies, but the com- plex interactions among the carbon (C), water, and nitrogen (N) cycles have not been adequately addressed in the current models. In this study, a process-based vegetation dynamic model was developed to study the responses of dryland ecosystems to environmental changes, emphasizing on the interactions among the C, water, and N proc- esses. To address the interactions between the C and water processes, it not only considers the effects of annual precipitation on vegetation distribution and soil moisture on organic matter (SOM) decomposition, but also explicitly models root competition for water and the water compensation processes. To address the interactions between C and N processes, it models the soil inorganic mater processes, such as N mineralization/immobilization, denitrifica- tion/nitrification, and N leaching, as well as the root competition for soil N. The model was parameterized for major plant functional types and evaluated against field observations.