A multi-level evaluation model for the superstructure of a damaged prestressed concrete girder or beam bridge is established, and the evaluation indices of the model as well as the rating standards are defined. A norm...A multi-level evaluation model for the superstructure of a damaged prestressed concrete girder or beam bridge is established, and the evaluation indices of the model as well as the rating standards are defined. A normal relative function about the evaluation indices of each element is developed to calculate the relative degree, and for each element there are no sub-level elements. When evaluating the elements in the sub-item level or the index level of the model, the weights of elements pertain to one adopted element, taking into account their degrees of deterioration. Since the relative degrees and structure evaluation scales on the damage conditions are applied to characterize the superstructure of damaged prestressed concrete girder bridges, this method can evaluate the prestressed structure in detail, and the evaluation results agree with the Code for Maintenance of Highway Bridges and Culvers (JTG Hll--2004 ). Finally, a bridge in Jilin province is taken as an example, using the method developed to evaluate its damage conditions, which gives an effective way for bridge engineering.展开更多
The objective evaluation to the terrace cultural landscape heritage value can provide targeted scientific basis for continuation of terrace culture landscape and establishment of protection measures. On the basis of f...The objective evaluation to the terrace cultural landscape heritage value can provide targeted scientific basis for continuation of terrace culture landscape and establishment of protection measures. On the basis of field investigation, expert consultation and literature review, combined with the AVC (Attraction、Vitality and Ca-pacity)theory and Analytic Hierarchy Process based on Fuzzy Comprehensive Evalu-ation, the terrace cultural landscape heritage protection evaluation system and eval-uation model, which selects 22 indicators from three levels including terrace culture landscape resources attraction, resources vitality and resources bearing capacity were structured. Based on col ection of data, material from field survey of China's most representative Yunnan Yuanyang Hani terrace, Hunan Ziquejie terrace and Longsheng Longji terrace and relevant mathematical calculation to determine evalua-tion index weights, organical y combined of qualitative with quantitative analysis, the diversity, reasonableness and accuracy of evaluation system is improved. Compre-hensive result of mathematical statistics showed that the rank of the cultural land-scape heritage value with the three most representative terraces in southern China is: γ(Hani)〉γ(Longji)〉γ(Ziquejie).展开更多
Urban construction land suitability evaluation (UCLSE) is a complex system engineering and the basis for rational use of the limited urban land resources in China. It has an important practical value on urban constr...Urban construction land suitability evaluation (UCLSE) is a complex system engineering and the basis for rational use of the limited urban land resources in China. It has an important practical value on urban construction land use planning and management from the angle of methodology. As a widely used technique, traditional multi-criteria evaluation based on GIS (MCE-GIS), is not suitable for UCLSE. This study develops an improved MCE-GIS method which could be more suitable for UCLSE based on urban complex ecological system theory and the summary of the shortcomings of traditional MCE-GIS. The improvements include three aspects: a composite evaluation index system rather than natural indexes alone, an index weight calculated by using fuzzy Analytic Hierarchy Process (AHP) method rather than the common AHP method, and the integrated overlay rule, which includes selecting the minimum value, weighted linear combination (WLC) and simple summation. The main advantage of this improved technique is that it can make UCLSE more comprehensive, more operational and more reasonable. It can provide a scientific basis for decision making in the planning and management of urban construction land use. The improved MCE-GIS system has been adopted in the New Hefei City, Anhui Province, China. Based on the results of UCLSE in New Hefei, three functional areas including construction-appropriate areas, construction-restricted areas and construction-forbidden areas could be worked out, in which 36.90% of the total study area could be developed as urban construction land and the remaining 63.10% should be protected as reserves land or as ecological land. Furthermore, the results can orovide scientific decision suooort for spatial planning and eco-environment nrotection in New Hefei.展开更多
The sustainable development of coal mining cities in Heilongjiang province has important effect on the economic stability and development of Heilongjiang, Northeast China, and China at large. To further the sustainabl...The sustainable development of coal mining cities in Heilongjiang province has important effect on the economic stability and development of Heilongjiang, Northeast China, and China at large. To further the sustainable development evaluation system of coal mining cities in Heilongjiang province, based on the analytic hierarchy process (AHP) method combined with operational and scientific principles using Saaty's 1-9 scale method to construct the judgment matrix from five aspects, such as economic development and environmental quality, this paper establishes the comprehensive evaluation index sys- tem of sustainable development of coal mining cities in Heilongjiang province, including comprehensive index of industrial economic benefits and the contribution rate of science and technology. In addition, using fuzzy comprehensive evaluation method, a comprehensive evaluation is made on the indices of the four major coal mining cities of Heilongjiang. The result shows that the coal mining cities are not bet- ter than Datong of Shanxi province in many indices. The economic development and environment quality are the most important indices of the targeted layer influencing the sustainable development of coal min- ing cities of HeilonKiiang, and their index weights are 0.4358 and 0.2844, respectively. These two indices including comprehensive index of industrial economic benefit and the ratio of environmental protection investment to GDP are the key elements influencing the two aspects.展开更多
The kinematic accuracy of space manipulator determines whether the spacecraft performs normally or not. Problems pertaining to structural deformation have received increased attention in recent times. In the space man...The kinematic accuracy of space manipulator determines whether the spacecraft performs normally or not. Problems pertaining to structural deformation have received increased attention in recent times. In the space manipulator systems, flexible arms and joints can induce drastic dynamic instabilities. In applications such as the space station, kinematic error due to structural deformation can jointly affect the performance characteristics. And it is crucial for accuracy control of space manipulator to establish a precision index. Here we analyze the dynamics characteristic of flexible space manipulator considering the hysteresis of harmonic reducer based on method of nonconstraint boundary modal. For the sake of describing the output accuracy, we integrate the method of analytic hierarchy process(AHP) to establish a comprehensive evaluation index. A numerical simulation is performed to analyze the nonlinear dynamic characteristics of space manipulator with harmonic reducer. With the analysis of accuracy assessment, the relation among the hysteresis angle, rigidity and output accuracy is revealed. Considering the elastic modulus of flexible space manipulator and the hysteresis angle of harmonic reducer, we conduct an evaluation of output characteristics of flexible space manipulator with the proposed comprehensive evaluation index. The accuracy evaluation of output characteristics based on the proposed comprehensive evaluation index is implemented in the initial stage of space manipulator's design, which can not only solve the problems existing in the design but also save cost savings for ground tests. The results can be used in designing and optimizing future space manipulators, which may provide valuable references for design and thermal control of the space manipulator.展开更多
文摘A multi-level evaluation model for the superstructure of a damaged prestressed concrete girder or beam bridge is established, and the evaluation indices of the model as well as the rating standards are defined. A normal relative function about the evaluation indices of each element is developed to calculate the relative degree, and for each element there are no sub-level elements. When evaluating the elements in the sub-item level or the index level of the model, the weights of elements pertain to one adopted element, taking into account their degrees of deterioration. Since the relative degrees and structure evaluation scales on the damage conditions are applied to characterize the superstructure of damaged prestressed concrete girder bridges, this method can evaluate the prestressed structure in detail, and the evaluation results agree with the Code for Maintenance of Highway Bridges and Culvers (JTG Hll--2004 ). Finally, a bridge in Jilin province is taken as an example, using the method developed to evaluate its damage conditions, which gives an effective way for bridge engineering.
基金Supported by Guangxi Scientific Research and Technology Development Program(14124005-2-4)Youth Tourism Expert Training Program of National Tourism Administration Operation System(TYETP201548,TYETP201445)+2 种基金Guangxi Education Department Qualification and Postgraduate Education Reform and Development Program(JGY2014077)Guangxi Superior and Characteristic Key Subject Open-end Fund(LYKF05)Guilin S&T Research and Development Program(20150110-5)~~
文摘The objective evaluation to the terrace cultural landscape heritage value can provide targeted scientific basis for continuation of terrace culture landscape and establishment of protection measures. On the basis of field investigation, expert consultation and literature review, combined with the AVC (Attraction、Vitality and Ca-pacity)theory and Analytic Hierarchy Process based on Fuzzy Comprehensive Evalu-ation, the terrace cultural landscape heritage protection evaluation system and eval-uation model, which selects 22 indicators from three levels including terrace culture landscape resources attraction, resources vitality and resources bearing capacity were structured. Based on col ection of data, material from field survey of China's most representative Yunnan Yuanyang Hani terrace, Hunan Ziquejie terrace and Longsheng Longji terrace and relevant mathematical calculation to determine evalua-tion index weights, organical y combined of qualitative with quantitative analysis, the diversity, reasonableness and accuracy of evaluation system is improved. Compre-hensive result of mathematical statistics showed that the rank of the cultural land-scape heritage value with the three most representative terraces in southern China is: γ(Hani)〉γ(Longji)〉γ(Ziquejie).
基金Under the auspices of National Natural Science Foundation of China(No.41201168)Fundamental Research Funds for the Central Universities(No.2013HGXJ0207)
文摘Urban construction land suitability evaluation (UCLSE) is a complex system engineering and the basis for rational use of the limited urban land resources in China. It has an important practical value on urban construction land use planning and management from the angle of methodology. As a widely used technique, traditional multi-criteria evaluation based on GIS (MCE-GIS), is not suitable for UCLSE. This study develops an improved MCE-GIS method which could be more suitable for UCLSE based on urban complex ecological system theory and the summary of the shortcomings of traditional MCE-GIS. The improvements include three aspects: a composite evaluation index system rather than natural indexes alone, an index weight calculated by using fuzzy Analytic Hierarchy Process (AHP) method rather than the common AHP method, and the integrated overlay rule, which includes selecting the minimum value, weighted linear combination (WLC) and simple summation. The main advantage of this improved technique is that it can make UCLSE more comprehensive, more operational and more reasonable. It can provide a scientific basis for decision making in the planning and management of urban construction land use. The improved MCE-GIS system has been adopted in the New Hefei City, Anhui Province, China. Based on the results of UCLSE in New Hefei, three functional areas including construction-appropriate areas, construction-restricted areas and construction-forbidden areas could be worked out, in which 36.90% of the total study area could be developed as urban construction land and the remaining 63.10% should be protected as reserves land or as ecological land. Furthermore, the results can orovide scientific decision suooort for spatial planning and eco-environment nrotection in New Hefei.
基金supported by the Philosophy and Social Science Program of Heilongjiang Province (No. 10D051)the Science and Technology Plan Program of Heilongjiang Province (No. GC10D209)the General Humanity and Social Science Program of Heilongjiang Provincial Universities in 2012 (HET-based energy sustainable development research of Heilongjiang province) (No. 12522258)
文摘The sustainable development of coal mining cities in Heilongjiang province has important effect on the economic stability and development of Heilongjiang, Northeast China, and China at large. To further the sustainable development evaluation system of coal mining cities in Heilongjiang province, based on the analytic hierarchy process (AHP) method combined with operational and scientific principles using Saaty's 1-9 scale method to construct the judgment matrix from five aspects, such as economic development and environmental quality, this paper establishes the comprehensive evaluation index sys- tem of sustainable development of coal mining cities in Heilongjiang province, including comprehensive index of industrial economic benefits and the contribution rate of science and technology. In addition, using fuzzy comprehensive evaluation method, a comprehensive evaluation is made on the indices of the four major coal mining cities of Heilongjiang. The result shows that the coal mining cities are not bet- ter than Datong of Shanxi province in many indices. The economic development and environment quality are the most important indices of the targeted layer influencing the sustainable development of coal min- ing cities of HeilonKiiang, and their index weights are 0.4358 and 0.2844, respectively. These two indices including comprehensive index of industrial economic benefit and the ratio of environmental protection investment to GDP are the key elements influencing the two aspects.
文摘The kinematic accuracy of space manipulator determines whether the spacecraft performs normally or not. Problems pertaining to structural deformation have received increased attention in recent times. In the space manipulator systems, flexible arms and joints can induce drastic dynamic instabilities. In applications such as the space station, kinematic error due to structural deformation can jointly affect the performance characteristics. And it is crucial for accuracy control of space manipulator to establish a precision index. Here we analyze the dynamics characteristic of flexible space manipulator considering the hysteresis of harmonic reducer based on method of nonconstraint boundary modal. For the sake of describing the output accuracy, we integrate the method of analytic hierarchy process(AHP) to establish a comprehensive evaluation index. A numerical simulation is performed to analyze the nonlinear dynamic characteristics of space manipulator with harmonic reducer. With the analysis of accuracy assessment, the relation among the hysteresis angle, rigidity and output accuracy is revealed. Considering the elastic modulus of flexible space manipulator and the hysteresis angle of harmonic reducer, we conduct an evaluation of output characteristics of flexible space manipulator with the proposed comprehensive evaluation index. The accuracy evaluation of output characteristics based on the proposed comprehensive evaluation index is implemented in the initial stage of space manipulator's design, which can not only solve the problems existing in the design but also save cost savings for ground tests. The results can be used in designing and optimizing future space manipulators, which may provide valuable references for design and thermal control of the space manipulator.