We present a novel incremental algorithm for non-slicing floorplans based on the corner block list representation. The horizontal and vertical adjacency graphs are derived from the packing of the initial floorplanning...We present a novel incremental algorithm for non-slicing floorplans based on the corner block list representation. The horizontal and vertical adjacency graphs are derived from the packing of the initial floorplanning results. Based on the critical path and the accumulated slack distances we define,we choose the best position for insertion and do a series of operations incrementally, such as deleting modules, adding modules, and resizing modules quickly. This incremental floorplanning algorithm has a very high speed less than 1μm,which is one of the most important measures in this research. The algorithm preserves the original good performances on area and wire length. It can also supply other tools with good physical estimates for area, wire length, and other performance guidelines.展开更多
This paper uses three size metrics,which are collectable during the design phase,to analyze the potentially confounding effect of class size on the associations between object-oriented（OO）metrics and maintainability...This paper uses three size metrics,which are collectable during the design phase,to analyze the potentially confounding effect of class size on the associations between object-oriented（OO）metrics and maintainability.To draw as many general conclusions as possible,the confounding effect of class size is analyzed on 127 C＋＋ systems and 113 Java systems.For each OO metric,the indirect effect that represents the distortion of the association caused by class size and its variance for individual systems is first computed.Then,a statistical meta-analysis technique is used to compute the average indirect effect over all the systems and to determine if it is significantly different from zero.The experimental results show that the confounding effects of class size on the associations between OO metrics and maintainability generally exist,regardless of whatever size metric is used.Therefore,empirical studies validating OO metrics on maintainability should consider class size as a confounding variable.展开更多
Current status and existing problems in the Chinese cosmetic industry areanalyzed from the aspects of industry scale, technology and management level, R&D investment andhuman resources. Strategies to promote the i...Current status and existing problems in the Chinese cosmetic industry areanalyzed from the aspects of industry scale, technology and management level, R&D investment andhuman resources. Strategies to promote the industry are also put forward, such as increasing entrybarrier to optimize industry structure, tightening regulatory controls to improve quality assurance,fostering innovation and actively exploring modes of collaboration, and training more technical andmanaging professionals.展开更多
Fuzzy association rules (FARs) can be powerful in assessing regional soil quality, a critical step prior to land planning and utilization; however, traditional FARs mined from soil quality database, ignoring the impor...Fuzzy association rules (FARs) can be powerful in assessing regional soil quality, a critical step prior to land planning and utilization; however, traditional FARs mined from soil quality database, ignoring the importance variability of the rules, can be redundant and far from optimal. In this study, we developed a method applying different weights to traditional FARs to improve accuracy of soil quality assessment. After the FARs for soil quality assessment were mined, redundant rules were eliminated according to whether the rules were significant or not in reducing the complexity of the soil quality assessment models and in improving the comprehensibility of FARs. The global weights, each representing the importance of a FAR in soil quality assessment, were then introduced and refined using a gradient descent optimization method. This method was applied to the assessment of soil resources conditions in Guangdong Province, China. The new approach had an accuracy of 87%, when 15 rules were mined, as compared with 76% from the traditional approach. The accuracy increased to 96% when 32 rules were mined, in contrast to 88% from the traditional approach. These results demonstrated an improved comprehensibility of FARs and a high accuracy of the proposed method.展开更多
A process composed of a fixed-bed and a distillation column with a side withdraw, mainly methanol, is developed to hydrolyze methyl acetate (MA) as a typical byproduct in polyvinyl alcohol (PVA) and pure terephthalic ...A process composed of a fixed-bed and a distillation column with a side withdraw, mainly methanol, is developed to hydrolyze methyl acetate (MA) as a typical byproduct in polyvinyl alcohol (PVA) and pure terephthalic acid (PTA) factory. The process is simulated by employing the equilibrium stage model RadFrac and plug flow model Rplug in Aspen Plus. Experiments are also carried out in a lab-scale to evaluate the process. The results show that at the molar ratio of water to methyl acetate about 4.0-5.0 in the feed stream and the volume ratio of distillate to feed MA above a critical value, the side product contains more than 80% (by mass) (MeOH) and less than 2% (by mass) MA, while the bottom contains more than 46% (by mass) acetic acid (HAc) and less than 0.5% (by mass) methanol with almost complete conversion of MA. Compared with the old catalytic distillation process we proposed before, this process can cut down 47.6% energy consumption and a distillation column.展开更多
In this paper the entanglement of pure 3-qubit states is discussed. The local unitary （LU） polynomial invariants that are closely related to the canonical forms are constructed and the relations of the coefficients ...In this paper the entanglement of pure 3-qubit states is discussed. The local unitary （LU） polynomial invariants that are closely related to the canonical forms are constructed and the relations of the coefficients of the canonical forms are given. Then the stochastic local operations and classlcal communication （SLOCC） classification of the states are discussed on the basis of the canonical forms, and the symmetric canonical form of the states without 3-tangle is discussed. Finally, we give the relation between the LU polynomial invariants and SLOCC classification.展开更多
Northeast China as one of important agricultural production bases is an area under reclamation and returning cultivated land to forests or pastures. Therefore, it is of great practical significance in guaranteeing the...Northeast China as one of important agricultural production bases is an area under reclamation and returning cultivated land to forests or pastures. Therefore, it is of great practical significance in guaranteeing the sustainable development and national food security to study the spatial and temporal variation of cultivated land in Northeast China under future climate scenarios. In this study, based on data of land use, natural environment and social-economy, dynamics of land system（DLS） model was used to to simulate the spatial distribution and changing trends of cultivated land in the typical areas of reclamation and returning cultivated land to forest or pastures in Northeast China during 2010-2030 under land use planning scenario and representative concentration pathways（RCPs） scenarios quantitatively.The results showed that the area of cultivated land had an overall decreasing trend under the land use planning scenario, but the area of upland field increased slightly from 2000 to 2010 and then declined greatly, while the area of paddy field continuously declined from 2000 to 2030. Under the Asia-Pacific Integrated model（AIM）scenario, the total area of cultivated land had a tendency to increase considerably,with the upland field expanding more obviously and the paddy field declining slightly.In addition, the cultivated land showed a greater decreasing trend under the model for energy supply strategy alternatives and their general environmental impact（MESSAGE） scenario compared to the land use planning scenario. Moreover, analysis on the conversion between different land use types indicated that the reclamation and returning cultivated land to forests or pastures was likely to continue under future scenarios, but the frequency of occurrence could decrease as the time goes by. The conclusions can provide significant decision-making information for the rational agricultural planning and cultivated land protection in Northeast China to adapt to the climate change.展开更多
文摘We present a novel incremental algorithm for non-slicing floorplans based on the corner block list representation. The horizontal and vertical adjacency graphs are derived from the packing of the initial floorplanning results. Based on the critical path and the accumulated slack distances we define,we choose the best position for insertion and do a series of operations incrementally, such as deleting modules, adding modules, and resizing modules quickly. This incremental floorplanning algorithm has a very high speed less than 1μm,which is one of the most important measures in this research. The algorithm preserves the original good performances on area and wire length. It can also supply other tools with good physical estimates for area, wire length, and other performance guidelines.
基金The National Natural Science Foundation of China(No.60425206,60633010)
文摘This paper uses three size metrics,which are collectable during the design phase,to analyze the potentially confounding effect of class size on the associations between object-oriented（OO）metrics and maintainability.To draw as many general conclusions as possible,the confounding effect of class size is analyzed on 127 C＋＋ systems and 113 Java systems.For each OO metric,the indirect effect that represents the distortion of the association caused by class size and its variance for individual systems is first computed.Then,a statistical meta-analysis technique is used to compute the average indirect effect over all the systems and to determine if it is significantly different from zero.The experimental results show that the confounding effects of class size on the associations between OO metrics and maintainability generally exist,regardless of whatever size metric is used.Therefore,empirical studies validating OO metrics on maintainability should consider class size as a confounding variable.
文摘Current status and existing problems in the Chinese cosmetic industry areanalyzed from the aspects of industry scale, technology and management level, R&D investment andhuman resources. Strategies to promote the industry are also put forward, such as increasing entrybarrier to optimize industry structure, tightening regulatory controls to improve quality assurance,fostering innovation and actively exploring modes of collaboration, and training more technical andmanaging professionals.
基金Supported by the National Natural Science Foundation of China (Nos.40671145 and 60573115)the Provincial Natural Science Foundation of Guangdong,China (Nos.04300504 and 05006623)
文摘Fuzzy association rules (FARs) can be powerful in assessing regional soil quality, a critical step prior to land planning and utilization; however, traditional FARs mined from soil quality database, ignoring the importance variability of the rules, can be redundant and far from optimal. In this study, we developed a method applying different weights to traditional FARs to improve accuracy of soil quality assessment. After the FARs for soil quality assessment were mined, redundant rules were eliminated according to whether the rules were significant or not in reducing the complexity of the soil quality assessment models and in improving the comprehensibility of FARs. The global weights, each representing the importance of a FAR in soil quality assessment, were then introduced and refined using a gradient descent optimization method. This method was applied to the assessment of soil resources conditions in Guangdong Province, China. The new approach had an accuracy of 87%, when 15 rules were mined, as compared with 76% from the traditional approach. The accuracy increased to 96% when 32 rules were mined, in contrast to 88% from the traditional approach. These results demonstrated an improved comprehensibility of FARs and a high accuracy of the proposed method.
基金Supported by the National Torch Program of China (2007HG560031)
文摘A process composed of a fixed-bed and a distillation column with a side withdraw, mainly methanol, is developed to hydrolyze methyl acetate (MA) as a typical byproduct in polyvinyl alcohol (PVA) and pure terephthalic acid (PTA) factory. The process is simulated by employing the equilibrium stage model RadFrac and plug flow model Rplug in Aspen Plus. Experiments are also carried out in a lab-scale to evaluate the process. The results show that at the molar ratio of water to methyl acetate about 4.0-5.0 in the feed stream and the volume ratio of distillate to feed MA above a critical value, the side product contains more than 80% (by mass) (MeOH) and less than 2% (by mass) MA, while the bottom contains more than 46% (by mass) acetic acid (HAc) and less than 0.5% (by mass) methanol with almost complete conversion of MA. Compared with the old catalytic distillation process we proposed before, this process can cut down 47.6% energy consumption and a distillation column.
基金The project supported by National Natural Science Foundation of China under Grant No. 6J3433050 and the Natural Science Foundation of Xuzhou Normal University （Key Project） under Grant No. 03XLA04
文摘In this paper the entanglement of pure 3-qubit states is discussed. The local unitary （LU） polynomial invariants that are closely related to the canonical forms are constructed and the relations of the coefficients of the canonical forms are given. Then the stochastic local operations and classlcal communication （SLOCC） classification of the states are discussed on the basis of the canonical forms, and the symmetric canonical form of the states without 3-tangle is discussed. Finally, we give the relation between the LU polynomial invariants and SLOCC classification.
基金Supported by the Major Research Project of National Natural Science Foundation Committee(91325302)China Postdoctoral Foundation(2014M560110)Hebei Social Science Foundation(HB15GL087)~~
文摘Northeast China as one of important agricultural production bases is an area under reclamation and returning cultivated land to forests or pastures. Therefore, it is of great practical significance in guaranteeing the sustainable development and national food security to study the spatial and temporal variation of cultivated land in Northeast China under future climate scenarios. In this study, based on data of land use, natural environment and social-economy, dynamics of land system（DLS） model was used to to simulate the spatial distribution and changing trends of cultivated land in the typical areas of reclamation and returning cultivated land to forest or pastures in Northeast China during 2010-2030 under land use planning scenario and representative concentration pathways（RCPs） scenarios quantitatively.The results showed that the area of cultivated land had an overall decreasing trend under the land use planning scenario, but the area of upland field increased slightly from 2000 to 2010 and then declined greatly, while the area of paddy field continuously declined from 2000 to 2030. Under the Asia-Pacific Integrated model（AIM）scenario, the total area of cultivated land had a tendency to increase considerably,with the upland field expanding more obviously and the paddy field declining slightly.In addition, the cultivated land showed a greater decreasing trend under the model for energy supply strategy alternatives and their general environmental impact（MESSAGE） scenario compared to the land use planning scenario. Moreover, analysis on the conversion between different land use types indicated that the reclamation and returning cultivated land to forests or pastures was likely to continue under future scenarios, but the frequency of occurrence could decrease as the time goes by. The conclusions can provide significant decision-making information for the rational agricultural planning and cultivated land protection in Northeast China to adapt to the climate change.
