The parametric part assembly generation method is presented. Based on the parametric part generated by means of constructive-element, through interactively inputting the relationships of the location and the assembly,...The parametric part assembly generation method is presented. Based on the parametric part generated by means of constructive-element, through interactively inputting the relationships of the location and the assembly, and by compiling operations like movement and rotation, the assembly drawing is created so as to implement the occurrence of the parameterizations of the assembly and the part drawing. The data structure of the assembly part and the key technologies of hidden line removal in the implementation of assembly process, etc. , are described in detail.展开更多
A new multi-level analysis method of introducing the super-element modeling method, derived from the multi-level analysis method first proposed by O. F. Hughes, has been proposed in this paper to solve the problem of ...A new multi-level analysis method of introducing the super-element modeling method, derived from the multi-level analysis method first proposed by O. F. Hughes, has been proposed in this paper to solve the problem of high time cost in adopting a rational-based optimal design method for ship structural design. Furthermore,the method was verified by its effective application in optimization of the mid-ship section of a container ship. A full 3-D FEM model of a ship,suffering static and quasi-static loads, was used as the analyzing object for evaluating the structural performance of the mid-ship module, including static strength and buckling performance. Research results reveal that this new method could substantially reduce the computational cost of the rational-based optimization problem without decreasing its accuracy, which increases the feasibility and economic efficiency of using a rational-based optimal design method in ship structural design.展开更多
The present work discusses a systematic approach to model grinding parameters of coal in a ball mill. A three level Box-Behnken design combined with response surface methodology using second order model was applied to...The present work discusses a systematic approach to model grinding parameters of coal in a ball mill. A three level Box-Behnken design combined with response surface methodology using second order model was applied to the experiments done according to the model requirement. Three parameters ball charge (numbers 10-20), coal content (100-200 g) and the grinding time (4-8 rain) were chosen for the experiments as well as for the modeling work. Coal fineness is defined as the dso (80 % passing size). A quadratic model was developed to show the effect of parameters and their interaction with fineness of the product. Three different sizes (4, 1 and 0.65 mm) of Indian coal were used. The model equations for each fraction were developed and different sets of experiments were performed. The predicted values of the fineness of coal were in good agreement with the experimental results (R2 values of dso varies between 0.97 and 0.99). Fine size of three different coal sizes were obtained with larger ball charge with less grinding time and less solid content. This work represents the efficient use of response surface methodology and the Box-Behnken design use for grinding of Indian coal.展开更多
An essential step for the realization of free-form surface structures is to create an efficient structural gird that satisfies not only the architectural aesthetics,but also the structural performance.Employing the ma...An essential step for the realization of free-form surface structures is to create an efficient structural gird that satisfies not only the architectural aesthetics,but also the structural performance.Employing the main stress trajectories as the representation of force flows on a free-form surface,an automatic grid generation approach is proposed for the architectural design.The algorithm automatically plots the main stress trajectories on a 3D free-form surface,and adopts a modified advancing front meshing technique to generate the structural grid.Based on the proposed algorithm,an automatic grid generator named "St-Surmesh" is developed for the practical architectural design of free-form surface structure.The surface geometry of one of the Sun Valleys in Expo Axis for the Expo Shanghai 2010 is selected as a numerical example for validating the proposed approach.Comparative studies are performed to demonstrate how different structural grids affect the design of a free-form surface structure.展开更多
Stope mining design is a very important and complicated task in daily production design and technical management of an underground mine.Based on workface technology and human-computer interaction technology,this study...Stope mining design is a very important and complicated task in daily production design and technical management of an underground mine.Based on workface technology and human-computer interaction technology,this study introduces a method of 3D parametric design for the irregular structure of stope bottoms,and focuses on solving technical problems in surface modeling of stope bottom structure.Optimization of the minimum span length algorithm(MSLA) and the shortest path search algorithm(SPSA) is conducted to solve the problem of contour-line based instant modeling of stope bottom structures,which makes possible the 3D parametric design for irregular structure of stope bottom.Implementation process and relevant methods of the proposed algorithms are also presented.Feasibility and reliability of the proposed modeling method are testified in a case study.In practice,the proposed 3 D parameterization design method for irregular structure stope bottom proves to be very helpful to precise 3D parametric design.This method is capable of contributing to improved efficiency and precision of stope design,and is worthy of promotion.展开更多
Weak rock zone (soft interlayer, fault zone and soft rock) is the highlight of large-scale geological engineering research. It is an important boundary for analysis of rock mass stability. Weak rock zone has been form...Weak rock zone (soft interlayer, fault zone and soft rock) is the highlight of large-scale geological engineering research. It is an important boundary for analysis of rock mass stability. Weak rock zone has been formed in a long geological period, and in this period, various rocks have undergone long-term consolidation of geostatic stress and tectonic stress; therefore, under in-situ conditions, their density and modulus of deformation are relatively high. Due to its fragmentary nature, once being exposed to the earth's surface, the structure of weak rock zone will soon be loosened, its density will be reduced, and its modulus of deformation will also be reduced significantly. Generally, weak rock zone can be found in large construction projects, especially in the dam foundation rocks of hydropower stations. These rocks cannot be eliminated completely by excavation. Furthermore, all tests nowadays are carried out after the exposure of weak rock zone, modulus of deformation under in-situ conditions cannot be revealed. In this paper, a test method explored by the authors has been introduced. This method is a whole multilayered medium deformation method. It is unnecessary to eliminate the relatively complete rocks covering on weak rock zone. A theoretical formula to obtain the modulus of deformation in various mediums has also been introduced. On-site comparative trials and indoor deformation modulus tests under equivalent density conditions have been carried out. We adopted several methods for the prediction researches of the deformation modulus of weak rock zone under in-situ conditions, and revealed a fact that under in-situ conditions, the deformation modulus of weak rock zone are several times higher than the test results obtained after the exposure. In a perspective of geological engineering, the research findings have fundamentally changed peoples' concepts on the deformation modulus of weak rock zone, provided important theories and methods for precise definition of deformation modulus of deep weak rock zone under cap rock conditions, as well as for reasonable engineering applications.展开更多
This article analyzes creation methods of automated design system, presents design system of a house foundation from blocks. The creation methods of automated design system of a house foundation from blocks are discov...This article analyzes creation methods of automated design system, presents design system of a house foundation from blocks. The creation methods of automated design system of a house foundation from blocks are discovered with Unified Modeling Language. Analyzed objects-classes: block, specification, model. Graphical system can design foundation, form specification of objects and create 3D model of house foundation. There are several types and different dimensions of concrete blocks. The program optimally arranges selected blocks so that monolithic parts will be minimal volume. Program selects a house foundation blocks from database by using ActiveX Data Objects technology, which by programming method connects drawing and database. Drawing's graphical objects have additional data from which exchange of data between graphical system and database is executed. Visualization system and example of house foundation from blocks project with specifications is presented. Creation problems of automated design system are discussed and conclusions are made.展开更多
This paper proposed an enhanced NEH with full insertion moves to solve the permutation flow shop problem.The characteristics of the original NEH are investigated and analyzed,and it is concluded that the given method ...This paper proposed an enhanced NEH with full insertion moves to solve the permutation flow shop problem.The characteristics of the original NEH are investigated and analyzed,and it is concluded that the given method would be promising to find better solutions,while the cost would be increased.Fast makespan calculating method and eliminating non-promising permutation policy are introduced to reduce the evaluation effort.The former decreases the time complexity from O(n4m) to O(n3m),which is an acceptable cost for medium and small size instances considering the obtained solution quality.The results from computational experience show that the latter also can eliminate a lot of non-promising solutions.展开更多
Hybrid modeling approaches have recently been investigated as an attractive alternative to model fermentation processes. Normally, these approaches require estimation data to train the empirical model part of a hybrid...Hybrid modeling approaches have recently been investigated as an attractive alternative to model fermentation processes. Normally, these approaches require estimation data to train the empirical model part of a hybrid model. This may result in decreasing the generalization ability of the derived hybrid model. Therefore, a simultaneous hybrid modeling approach is presented in this paper. It transforms the training of the empirical model part into a dynamic system parameter identification problem, and thus allows training the empirical model part with only measured data. An adaptive escaping particle swarm optimization(AEPSO) algorithm with escaping and adaptive inertia weight adjustment strategies is constructed to solve the resulting parameter identification problem, and thereby accomplish the training of the empirical model part. The uniform design method is used to determine the empirical model structure. The proposed simultaneous hybrid modeling approach has been used in a lab-scale nosiheptide batch fermentation process. The results show that it is effective and leads to a more consistent model with better generalization ability when compared to existing ones. The performance of AEPSO is also demonstrated.展开更多
With the income increase of elderly people in Beijing and the improvement of leisure facilities since 2000, the quality of elderly people leisure life in Beijing has obviously increased com- pared to ten years ago. Ac...With the income increase of elderly people in Beijing and the improvement of leisure facilities since 2000, the quality of elderly people leisure life in Beijing has obviously increased com- pared to ten years ago. According to the investigation and com- parative analysis on more than 900 elderly people, who usually exercise in public parks in Beijing City, we have found out several new features of elderly people's outdoor recreation in Belting: the increase of the leisure time, the expansion of leisure space, the in- dividuation of interest and the diversification of consumption. The leisure life quality evaluation index system of urban elderly people can be built based on these analyses. In order to accommodate the development tendency of elderly people's demand for leisure diversification, we should strengthen the organization and manage- ment of elderly people's leisure activity in urban construction, and pay more attention to function complementation between commu- nities and parks.展开更多
ISO 13584 (i.e. PLIB) is an international standard for the representation and exchange of CAD part libraries. It aims to provide an application-independent mechanism to enable the share of part library information bet...ISO 13584 (i.e. PLIB) is an international standard for the representation and exchange of CAD part libraries. It aims to provide an application-independent mechanism to enable the share of part library information between applications. In this paper, the approach of modeling part library conforming to ISO 13584 is presented. Also, a prototype of part library management system, i.e. BYL-PLIB, whose implementation is in agreement with ISO 13854 is developed to demonstrate the usefulness of proposed approach.展开更多
First, the high-rise building structure design process is divided into three relevant steps, that is, scheme generation and creation, performance evaluation, and scheme optimization. Then with the application of relat...First, the high-rise building structure design process is divided into three relevant steps, that is, scheme generation and creation, performance evaluation, and scheme optimization. Then with the application of relational database, the case database of high-rise structures is constructed, the structure form-selection designing methods such as the smart algorithm based on CBR, DM, FINS, NN and GA is presented, and the original forms system of this method and its general structure are given. CBR and DM are used to generate scheme candidates; FINS and NN to evaluate and optimize the scheme performance; GA to create new structure forms. Finally, the application cases are presented, whose results fit in with the real project. It proves by combining and using the expert intelligence, algorithm intelligence and machine intelligence that this method makes good use of not only the engineering project knowledge and expertise but also much deeper knowledge contained in various engineering cases. In other words, it is because the form selection has a strong background support of vast real cases that its results prove more reliable and more acceptable. So the introduction of this method provides an effective approach to improving the quality, efficiency, automatic and smart level of high-rise structures form selection design.展开更多
Understanding vertebrate habitat relationships is important to promote management strategies for the longterm conservation of many species. Using a modified drift fence method, we sampled reptiles and compared habitat...Understanding vertebrate habitat relationships is important to promote management strategies for the longterm conservation of many species. Using a modified drift fence method, we sampled reptiles and compared habitat variables within the William B. Bankhead National Forest (BNF) in Alabama, U.S.A from April 2005 to June 2006. We captured 226 individual reptiles representing 19 species during 564 total trap nights. We used canonical correspondence analysis to examine habitat associations for the reptiles sampled and we detected a distinct habitat gradient ranging from sites with greater litter depth and percent canopy cover to more open sites with greater woody, herbaceous, and coarse woody debris (CWD) coverage, and CWD volume. Little brown skinks Scincella lateralis and eastern worm snakes Carphophis a. arnoenus were associated with sites with greater litter depth and canopy cover, whereas eastern fence lizards Sceloporus undulatus, copperheads Agkistrodon contortrix, and gray ratsnakes Pantherophis spiloides were associated with sites possessing greater CWD coverage and volume. We found that disturbances due to the southern pine beetle Dendroctonus frontalis were likely important for influencing reptile distributions through the creation of canopy gaps and fallen coarse woody debris. Compared to other studies, our modified drift-fence trap technique was successful for sampling larger snake species (66 snakes in 564 trap nights). We have also provided detailed schematics for constructing drift fence array and box traps used in this study展开更多
In contrast to the input perspective for evaluating planning metrics, this research takes the climatic environmental output effects as the starting point for assessing ecological city construction. Based on approaches...In contrast to the input perspective for evaluating planning metrics, this research takes the climatic environmental output effects as the starting point for assessing ecological city construction. Based on approaches such as observation data analysis, meteorological model simulation, and remote sensing, a set of climatic environmental performance assessment methods is developed and established. These methods mainly focus on surface ventilation assessment and urban thermal environment assessment. With the Yanqi Lake ecological development demonstration area located in Huairou district, Beijing as an example, the assessment of the local climatic environment before and after the construction are conducted, and relevant policy suggestions for urban planning and construction are presented. The results show that after development, the ventilation capacity will decrease overall and the ventilation potential index will decrease from 0.53 to 0.44. While this is not a large reduction, and is still at a favorable level, the ventilation potential in some local areas will markedly decrease. Furthermore, the thermal environment will become poorer to some extent; the urban heat island(UHI) area and intensity will increase compared with the current situation;continuous heat islands may occur in local areas; the UHI potential index of the core area will rise from 0.0878 to 0.1217(still a favorable level).Therefore, urban surfaces should be carefully developed and arranged during planning. It is suggested that the negative impacts of large areas of urban construction on the local climatic environment in the Yanqi Lake could be mitigated by 1) strengthening the airflow by introducing fresh,cold, northwesterly air via constructed ventilation corridors, 2) increasing the number of ecological cold sources, particularly for water bodies and green belts to prevent the UHI in the southern region of Yanqi Lake from becoming linked with each other, and 3) considering a pre-program before sub-domain and building planning to obtain optimum building locations. Different construction standards should be developed for different ventilation potential and UHI intensity levels. For strong heat island areas, land areas should be reserved to serve as cold sources.展开更多
Soils with strain-softening behavior — manifesting as a reduction of strength with increasing plastic strain — are commonly found in the natural environment. For slopes in these soils,a progressive failure mechanism...Soils with strain-softening behavior — manifesting as a reduction of strength with increasing plastic strain — are commonly found in the natural environment. For slopes in these soils,a progressive failure mechanism can occur due to a reduction of strength with increasing strain. Finite element method based numerical approaches have been widely performed for simulating such failure mechanism,owning to their ability for tracing the formation and development of the localized shear strain. However,the reliability of the currently used approaches are often affected by poor convergence or significant mesh-dependency,and their applicability is limited by the use of complicated soil models. This paper aims to overcome these limitations by developing a finite element approach using a local arc-length controlled iterative algorithm as the solution strategy. In the proposed finite element approach,the soils are simulated with an elastoplastic constitutive model in conjunction with the Mohr-Coulomb yield function. The strain-softening behavior is represented by a piece-wise linearrelationship between the Mohr-Coulomb strength parameters and the deviatoric plastic strain. To assess the reliability of the proposed finite element approach,comparisons of the numerical solutions obtained by different finite element methods and meshes with various qualities are presented. Moreover,a landslide triggered by excavation in a real expressway construction project is analyzed by the presented finite element approach to demonstrate its applicability for practical engineering problems.展开更多
In order to strengthen cost control in construction project bidding stage, this paper takes the price control in bidding stage as the main line, dedicated to determine the key point in the stage of cost control, and e...In order to strengthen cost control in construction project bidding stage, this paper takes the price control in bidding stage as the main line, dedicated to determine the key point in the stage of cost control, and establishes the more objective and reasonable evaluation in view of the comprehensive evaluation method, and combined with the practical application of engineering to demonstrate. This paper not only improved the tendering and bidding stage method of cost control in construction project in our country, and improves the method system of engineering cost control.展开更多
The developed modem control systems and buildings management resource systems would be effective if they are based on previously established optimal conditions during the building design. This is one of the key issues...The developed modem control systems and buildings management resource systems would be effective if they are based on previously established optimal conditions during the building design. This is one of the key issues for a responsible architecture. The focus of this paper is on sustainable design methods and techniques for saving resources and their management throughout the building lifecycle. The main subject of the present article is the characteristics of these methods and their fundamental role in sustainable resource management during the building operation. The results which are based on conducted case studies of European and international practice in the construction of sustainable buildings are implemented here. Key features of a comprehensive approach for design and construction are outlined via comparative analysis, as well as various systems for the evaluation of sustainability for already constructed buildings. The mostly used criteria and indicators for sustainability are systematized, including those related to resource consumption. By analyzing a specific example, the role of sustainable design methods is justified as an important prerequisite for effective management of building resources in the process building maintenance. According to the conducted studies, during the longest life cycle period of a building, by implementation of control systems and resource management of building, the costs are successfully optimized. Specific directions that prove the effectiveness of such systems are systematized in the paper. Innovative approaches, complex methods and measures for design and management of buildings resources are presented as results of this study.展开更多
High-density housing can be interpreted as collections of individual units, which inevitably results in the dilemma between the global standardization designed by architects and local customization implemented by user...High-density housing can be interpreted as collections of individual units, which inevitably results in the dilemma between the global standardization designed by architects and local customization implemented by users. However, it is impossible to reflect the users' various needs in the conceptual design stage for high-density housing because of the economic, industrial and time constrains. In response to this challenge, this research paper outlines a different high-density housing design approach that can adopt users' individual customization in the conceptual design stage during the housing design practice. Hence, the design process would be an open-ended evolutionary and transparent process rather than deterministic executions as we have now in most high-density cities, such as Hong Kong. In order to overcome the deficiency in addressing future uncertainties of different users and address the issues of one-off developments without iterating users' feedback in the housing practice, this essay proposes IOSDA (integrated open source design for architecture) for the design practice of high-density housing, through collective data and parametric connectivity between users and architects. IOSDA reflects a different design attitude towards the future, i.e., to shift from architects' heroic prediction of the future to collective engagement of the present with more robust capacities for new possibilities.展开更多
The introduction of information technology and computers in the design process enables easier, faster and more accurate design of welding technology, as well as higher quality, repeatability and traceability of proces...The introduction of information technology and computers in the design process enables easier, faster and more accurate design of welding technology, as well as higher quality, repeatability and traceability of processes. This paper presents the modeling of welded construction maintenance activities by IDEF0 (Integration DEFinition) methodology. Modeling maintenance activities on a welded construction using IDEF0 methodology, the software implementation of which is the BPWin (Business Process windows) CASE (Computer Aided Software Engineering) tool, allows functional decomposition and design at all levels of the system that consists of workers, machines, materials, computers and information.展开更多
文摘The parametric part assembly generation method is presented. Based on the parametric part generated by means of constructive-element, through interactively inputting the relationships of the location and the assembly, and by compiling operations like movement and rotation, the assembly drawing is created so as to implement the occurrence of the parameterizations of the assembly and the part drawing. The data structure of the assembly part and the key technologies of hidden line removal in the implementation of assembly process, etc. , are described in detail.
基金Supported by the Project of Ministry of Education and Finance(No.200512)the Project of the State Key Laboratory of ocean engineering(GKZD010053-10)
文摘A new multi-level analysis method of introducing the super-element modeling method, derived from the multi-level analysis method first proposed by O. F. Hughes, has been proposed in this paper to solve the problem of high time cost in adopting a rational-based optimal design method for ship structural design. Furthermore,the method was verified by its effective application in optimization of the mid-ship section of a container ship. A full 3-D FEM model of a ship,suffering static and quasi-static loads, was used as the analyzing object for evaluating the structural performance of the mid-ship module, including static strength and buckling performance. Research results reveal that this new method could substantially reduce the computational cost of the rational-based optimization problem without decreasing its accuracy, which increases the feasibility and economic efficiency of using a rational-based optimal design method in ship structural design.
文摘The present work discusses a systematic approach to model grinding parameters of coal in a ball mill. A three level Box-Behnken design combined with response surface methodology using second order model was applied to the experiments done according to the model requirement. Three parameters ball charge (numbers 10-20), coal content (100-200 g) and the grinding time (4-8 rain) were chosen for the experiments as well as for the modeling work. Coal fineness is defined as the dso (80 % passing size). A quadratic model was developed to show the effect of parameters and their interaction with fineness of the product. Three different sizes (4, 1 and 0.65 mm) of Indian coal were used. The model equations for each fraction were developed and different sets of experiments were performed. The predicted values of the fineness of coal were in good agreement with the experimental results (R2 values of dso varies between 0.97 and 0.99). Fine size of three different coal sizes were obtained with larger ball charge with less grinding time and less solid content. This work represents the efficient use of response surface methodology and the Box-Behnken design use for grinding of Indian coal.
基金Project(51378457)supported by the National Natural Science Foundation of China
文摘An essential step for the realization of free-form surface structures is to create an efficient structural gird that satisfies not only the architectural aesthetics,but also the structural performance.Employing the main stress trajectories as the representation of force flows on a free-form surface,an automatic grid generation approach is proposed for the architectural design.The algorithm automatically plots the main stress trajectories on a 3D free-form surface,and adopts a modified advancing front meshing technique to generate the structural grid.Based on the proposed algorithm,an automatic grid generator named "St-Surmesh" is developed for the practical architectural design of free-form surface structure.The surface geometry of one of the Sun Valleys in Expo Axis for the Expo Shanghai 2010 is selected as a numerical example for validating the proposed approach.Comparative studies are performed to demonstrate how different structural grids affect the design of a free-form surface structure.
基金Supported by the National High Technology Research and Development Programme of China(No.2011AA060407)Yunnan Province Science and Technology Innovation Platform Construction Plans,China(No.2010DH005)
文摘Stope mining design is a very important and complicated task in daily production design and technical management of an underground mine.Based on workface technology and human-computer interaction technology,this study introduces a method of 3D parametric design for the irregular structure of stope bottoms,and focuses on solving technical problems in surface modeling of stope bottom structure.Optimization of the minimum span length algorithm(MSLA) and the shortest path search algorithm(SPSA) is conducted to solve the problem of contour-line based instant modeling of stope bottom structures,which makes possible the 3D parametric design for irregular structure of stope bottom.Implementation process and relevant methods of the proposed algorithms are also presented.Feasibility and reliability of the proposed modeling method are testified in a case study.In practice,the proposed 3 D parameterization design method for irregular structure stope bottom proves to be very helpful to precise 3D parametric design.This method is capable of contributing to improved efficiency and precision of stope design,and is worthy of promotion.
文摘Weak rock zone (soft interlayer, fault zone and soft rock) is the highlight of large-scale geological engineering research. It is an important boundary for analysis of rock mass stability. Weak rock zone has been formed in a long geological period, and in this period, various rocks have undergone long-term consolidation of geostatic stress and tectonic stress; therefore, under in-situ conditions, their density and modulus of deformation are relatively high. Due to its fragmentary nature, once being exposed to the earth's surface, the structure of weak rock zone will soon be loosened, its density will be reduced, and its modulus of deformation will also be reduced significantly. Generally, weak rock zone can be found in large construction projects, especially in the dam foundation rocks of hydropower stations. These rocks cannot be eliminated completely by excavation. Furthermore, all tests nowadays are carried out after the exposure of weak rock zone, modulus of deformation under in-situ conditions cannot be revealed. In this paper, a test method explored by the authors has been introduced. This method is a whole multilayered medium deformation method. It is unnecessary to eliminate the relatively complete rocks covering on weak rock zone. A theoretical formula to obtain the modulus of deformation in various mediums has also been introduced. On-site comparative trials and indoor deformation modulus tests under equivalent density conditions have been carried out. We adopted several methods for the prediction researches of the deformation modulus of weak rock zone under in-situ conditions, and revealed a fact that under in-situ conditions, the deformation modulus of weak rock zone are several times higher than the test results obtained after the exposure. In a perspective of geological engineering, the research findings have fundamentally changed peoples' concepts on the deformation modulus of weak rock zone, provided important theories and methods for precise definition of deformation modulus of deep weak rock zone under cap rock conditions, as well as for reasonable engineering applications.
文摘This article analyzes creation methods of automated design system, presents design system of a house foundation from blocks. The creation methods of automated design system of a house foundation from blocks are discovered with Unified Modeling Language. Analyzed objects-classes: block, specification, model. Graphical system can design foundation, form specification of objects and create 3D model of house foundation. There are several types and different dimensions of concrete blocks. The program optimally arranges selected blocks so that monolithic parts will be minimal volume. Program selects a house foundation blocks from database by using ActiveX Data Objects technology, which by programming method connects drawing and database. Drawing's graphical objects have additional data from which exchange of data between graphical system and database is executed. Visualization system and example of house foundation from blocks project with specifications is presented. Creation problems of automated design system are discussed and conclusions are made.
基金New Century Excellent Talents in University (No.NCET04-0383)Science and Technology Phosphor Program of Shanghai (No.04QMH1405)
文摘This paper proposed an enhanced NEH with full insertion moves to solve the permutation flow shop problem.The characteristics of the original NEH are investigated and analyzed,and it is concluded that the given method would be promising to find better solutions,while the cost would be increased.Fast makespan calculating method and eliminating non-promising permutation policy are introduced to reduce the evaluation effort.The former decreases the time complexity from O(n4m) to O(n3m),which is an acceptable cost for medium and small size instances considering the obtained solution quality.The results from computational experience show that the latter also can eliminate a lot of non-promising solutions.
基金Supported by the Specialized Research Fund for the Doctoral Program of Higher Education(No.20120042120014)
文摘Hybrid modeling approaches have recently been investigated as an attractive alternative to model fermentation processes. Normally, these approaches require estimation data to train the empirical model part of a hybrid model. This may result in decreasing the generalization ability of the derived hybrid model. Therefore, a simultaneous hybrid modeling approach is presented in this paper. It transforms the training of the empirical model part into a dynamic system parameter identification problem, and thus allows training the empirical model part with only measured data. An adaptive escaping particle swarm optimization(AEPSO) algorithm with escaping and adaptive inertia weight adjustment strategies is constructed to solve the resulting parameter identification problem, and thereby accomplish the training of the empirical model part. The uniform design method is used to determine the empirical model structure. The proposed simultaneous hybrid modeling approach has been used in a lab-scale nosiheptide batch fermentation process. The results show that it is effective and leads to a more consistent model with better generalization ability when compared to existing ones. The performance of AEPSO is also demonstrated.
基金support of Key Project of Chinese Ministry of Education (Grant No. 170170)
文摘With the income increase of elderly people in Beijing and the improvement of leisure facilities since 2000, the quality of elderly people leisure life in Beijing has obviously increased com- pared to ten years ago. According to the investigation and com- parative analysis on more than 900 elderly people, who usually exercise in public parks in Beijing City, we have found out several new features of elderly people's outdoor recreation in Belting: the increase of the leisure time, the expansion of leisure space, the in- dividuation of interest and the diversification of consumption. The leisure life quality evaluation index system of urban elderly people can be built based on these analyses. In order to accommodate the development tendency of elderly people's demand for leisure diversification, we should strengthen the organization and manage- ment of elderly people's leisure activity in urban construction, and pay more attention to function complementation between commu- nities and parks.
文摘ISO 13584 (i.e. PLIB) is an international standard for the representation and exchange of CAD part libraries. It aims to provide an application-independent mechanism to enable the share of part library information between applications. In this paper, the approach of modeling part library conforming to ISO 13584 is presented. Also, a prototype of part library management system, i.e. BYL-PLIB, whose implementation is in agreement with ISO 13854 is developed to demonstrate the usefulness of proposed approach.
文摘First, the high-rise building structure design process is divided into three relevant steps, that is, scheme generation and creation, performance evaluation, and scheme optimization. Then with the application of relational database, the case database of high-rise structures is constructed, the structure form-selection designing methods such as the smart algorithm based on CBR, DM, FINS, NN and GA is presented, and the original forms system of this method and its general structure are given. CBR and DM are used to generate scheme candidates; FINS and NN to evaluate and optimize the scheme performance; GA to create new structure forms. Finally, the application cases are presented, whose results fit in with the real project. It proves by combining and using the expert intelligence, algorithm intelligence and machine intelligence that this method makes good use of not only the engineering project knowledge and expertise but also much deeper knowledge contained in various engineering cases. In other words, it is because the form selection has a strong background support of vast real cases that its results prove more reliable and more acceptable. So the introduction of this method provides an effective approach to improving the quality, efficiency, automatic and smart level of high-rise structures form selection design.
基金provided by the USDA Forest Service Southern Research Stationthe National Science Foundation
文摘Understanding vertebrate habitat relationships is important to promote management strategies for the longterm conservation of many species. Using a modified drift fence method, we sampled reptiles and compared habitat variables within the William B. Bankhead National Forest (BNF) in Alabama, U.S.A from April 2005 to June 2006. We captured 226 individual reptiles representing 19 species during 564 total trap nights. We used canonical correspondence analysis to examine habitat associations for the reptiles sampled and we detected a distinct habitat gradient ranging from sites with greater litter depth and percent canopy cover to more open sites with greater woody, herbaceous, and coarse woody debris (CWD) coverage, and CWD volume. Little brown skinks Scincella lateralis and eastern worm snakes Carphophis a. arnoenus were associated with sites with greater litter depth and canopy cover, whereas eastern fence lizards Sceloporus undulatus, copperheads Agkistrodon contortrix, and gray ratsnakes Pantherophis spiloides were associated with sites possessing greater CWD coverage and volume. We found that disturbances due to the southern pine beetle Dendroctonus frontalis were likely important for influencing reptile distributions through the creation of canopy gaps and fallen coarse woody debris. Compared to other studies, our modified drift-fence trap technique was successful for sampling larger snake species (66 snakes in 564 trap nights). We have also provided detailed schematics for constructing drift fence array and box traps used in this study
基金sponsored by Beijing Municipal Science and Technology Project(Z131100001113026)the Program of the Research and Innovation Team on Urban Climate Assessment of Beijing Meteorological Bureau,Climate Change Special Foundation of China Meteorology Administration(CCSF201506)+1 种基金Science and technology project of Beijing Meteorological Bureau(BMBKJ201402002)National Natural Science Foundation of China(71473146)
文摘In contrast to the input perspective for evaluating planning metrics, this research takes the climatic environmental output effects as the starting point for assessing ecological city construction. Based on approaches such as observation data analysis, meteorological model simulation, and remote sensing, a set of climatic environmental performance assessment methods is developed and established. These methods mainly focus on surface ventilation assessment and urban thermal environment assessment. With the Yanqi Lake ecological development demonstration area located in Huairou district, Beijing as an example, the assessment of the local climatic environment before and after the construction are conducted, and relevant policy suggestions for urban planning and construction are presented. The results show that after development, the ventilation capacity will decrease overall and the ventilation potential index will decrease from 0.53 to 0.44. While this is not a large reduction, and is still at a favorable level, the ventilation potential in some local areas will markedly decrease. Furthermore, the thermal environment will become poorer to some extent; the urban heat island(UHI) area and intensity will increase compared with the current situation;continuous heat islands may occur in local areas; the UHI potential index of the core area will rise from 0.0878 to 0.1217(still a favorable level).Therefore, urban surfaces should be carefully developed and arranged during planning. It is suggested that the negative impacts of large areas of urban construction on the local climatic environment in the Yanqi Lake could be mitigated by 1) strengthening the airflow by introducing fresh,cold, northwesterly air via constructed ventilation corridors, 2) increasing the number of ecological cold sources, particularly for water bodies and green belts to prevent the UHI in the southern region of Yanqi Lake from becoming linked with each other, and 3) considering a pre-program before sub-domain and building planning to obtain optimum building locations. Different construction standards should be developed for different ventilation potential and UHI intensity levels. For strong heat island areas, land areas should be reserved to serve as cold sources.
基金funded by the Chinese National Basic Research Program (2010CB731503)
文摘Soils with strain-softening behavior — manifesting as a reduction of strength with increasing plastic strain — are commonly found in the natural environment. For slopes in these soils,a progressive failure mechanism can occur due to a reduction of strength with increasing strain. Finite element method based numerical approaches have been widely performed for simulating such failure mechanism,owning to their ability for tracing the formation and development of the localized shear strain. However,the reliability of the currently used approaches are often affected by poor convergence or significant mesh-dependency,and their applicability is limited by the use of complicated soil models. This paper aims to overcome these limitations by developing a finite element approach using a local arc-length controlled iterative algorithm as the solution strategy. In the proposed finite element approach,the soils are simulated with an elastoplastic constitutive model in conjunction with the Mohr-Coulomb yield function. The strain-softening behavior is represented by a piece-wise linearrelationship between the Mohr-Coulomb strength parameters and the deviatoric plastic strain. To assess the reliability of the proposed finite element approach,comparisons of the numerical solutions obtained by different finite element methods and meshes with various qualities are presented. Moreover,a landslide triggered by excavation in a real expressway construction project is analyzed by the presented finite element approach to demonstrate its applicability for practical engineering problems.
文摘In order to strengthen cost control in construction project bidding stage, this paper takes the price control in bidding stage as the main line, dedicated to determine the key point in the stage of cost control, and establishes the more objective and reasonable evaluation in view of the comprehensive evaluation method, and combined with the practical application of engineering to demonstrate. This paper not only improved the tendering and bidding stage method of cost control in construction project in our country, and improves the method system of engineering cost control.
文摘The developed modem control systems and buildings management resource systems would be effective if they are based on previously established optimal conditions during the building design. This is one of the key issues for a responsible architecture. The focus of this paper is on sustainable design methods and techniques for saving resources and their management throughout the building lifecycle. The main subject of the present article is the characteristics of these methods and their fundamental role in sustainable resource management during the building operation. The results which are based on conducted case studies of European and international practice in the construction of sustainable buildings are implemented here. Key features of a comprehensive approach for design and construction are outlined via comparative analysis, as well as various systems for the evaluation of sustainability for already constructed buildings. The mostly used criteria and indicators for sustainability are systematized, including those related to resource consumption. By analyzing a specific example, the role of sustainable design methods is justified as an important prerequisite for effective management of building resources in the process building maintenance. According to the conducted studies, during the longest life cycle period of a building, by implementation of control systems and resource management of building, the costs are successfully optimized. Specific directions that prove the effectiveness of such systems are systematized in the paper. Innovative approaches, complex methods and measures for design and management of buildings resources are presented as results of this study.
文摘High-density housing can be interpreted as collections of individual units, which inevitably results in the dilemma between the global standardization designed by architects and local customization implemented by users. However, it is impossible to reflect the users' various needs in the conceptual design stage for high-density housing because of the economic, industrial and time constrains. In response to this challenge, this research paper outlines a different high-density housing design approach that can adopt users' individual customization in the conceptual design stage during the housing design practice. Hence, the design process would be an open-ended evolutionary and transparent process rather than deterministic executions as we have now in most high-density cities, such as Hong Kong. In order to overcome the deficiency in addressing future uncertainties of different users and address the issues of one-off developments without iterating users' feedback in the housing practice, this essay proposes IOSDA (integrated open source design for architecture) for the design practice of high-density housing, through collective data and parametric connectivity between users and architects. IOSDA reflects a different design attitude towards the future, i.e., to shift from architects' heroic prediction of the future to collective engagement of the present with more robust capacities for new possibilities.
文摘The introduction of information technology and computers in the design process enables easier, faster and more accurate design of welding technology, as well as higher quality, repeatability and traceability of processes. This paper presents the modeling of welded construction maintenance activities by IDEF0 (Integration DEFinition) methodology. Modeling maintenance activities on a welded construction using IDEF0 methodology, the software implementation of which is the BPWin (Business Process windows) CASE (Computer Aided Software Engineering) tool, allows functional decomposition and design at all levels of the system that consists of workers, machines, materials, computers and information.