In order to provide important parameters for schedule designing, decision-making bases for transit operation management and references for passengers traveling by bus, bus transit travel time reliability is analyzed a...In order to provide important parameters for schedule designing, decision-making bases for transit operation management and references for passengers traveling by bus, bus transit travel time reliability is analyzed and evaluated based on automatic vehicle location (AVL) data. Based on the statistical analysis of the bus transit travel time, six indices including the coefficient of variance, the width of travel time distribution, the mean commercial speed, the congestion frequency, the planning time index and the buffer time index are proposed. Moreover, a framework for evaluating bus transit travel time reliability is constructed. Finally, a case study on a certain bus route in Suzhou is conducted. Results show that the proposed evaluation index system is simple and intuitive, and it can effectively reflect the efficiency and stability of bus operations. And a distinguishing feature of bus transit travel time reliability is the temporal pattern. It varies across different time periods.展开更多
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
Pai Town-Medog County Route is known as the first hiking route in China, which is a part of Tibet tourism product, as well as a business card of Linzhi tourism. The route is abundant with natural and human resources. ...Pai Town-Medog County Route is known as the first hiking route in China, which is a part of Tibet tourism product, as well as a business card of Linzhi tourism. The route is abundant with natural and human resources. In the research, quantitative and qualitative methods were integrated and scientific evaluation and analysis were made on tourism resources along the route according to National Standard of Classification, Investigation and Evaluation of Tourism Resources, with countermeasures proposed.展开更多
To integrate different renewable energy resources effectively in a microgrid, a configuration optimization model of a multi-energy distributed generation(DG) system and its auxiliary equipment is proposed. The model...To integrate different renewable energy resources effectively in a microgrid, a configuration optimization model of a multi-energy distributed generation(DG) system and its auxiliary equipment is proposed. The model mainly consists of two parts, the determination of initial configuration schemes according to user preference and the selection of the optimal scheme. The comprehensive evaluation index(CEI), which is acquired through the analytic hierarchy process(AHP) weight calculation method, is adopted as the evaluation criterion to rank the initial schemes. The optimal scheme is obtained according to the ranking results. The proposed model takes the diversity of different equipment parameters and investment cost into consideration and can give relatively suitable and economical suggestions for system configuration.Additionally, unlike Homer Pro, the proposed model considers the complementation of different renewable energy resources, and thus the rationality of the multi-energy DG system is improved compared with the single evaluation criterion method which only considers the total cost.展开更多
Selecting six indexs of pH, DO, COD, BOD5, ammonia nitrogen and petroleum hydrocarbons in Haihe River Basin of four seasons in 2012 - 2013 for factor analysis, appling Water Quality Pollution Index (API) to evaluate...Selecting six indexs of pH, DO, COD, BOD5, ammonia nitrogen and petroleum hydrocarbons in Haihe River Basin of four seasons in 2012 - 2013 for factor analysis, appling Water Quality Pollution Index (API) to evaluate DO, COD, BOD5 and ammonia nitrogen, aims for systematic evluation to water quality of Haihe River Basin The results showed that two stations of B J1 and HB2 were the 1V type of water, others were the V type; Water Quality Pollution Index (API) was 1.44, which illustrated Haihe River Basin in the state of contamination that the degree of pollution exceeded the standard of functional areas. Factor Analysis explained that between COD, DO and NH3-N were significant difference (P〈0.05); principal component analysis showed that, in addition to pH and BOD5, the other indicators were above 0.70; the contribution rate of COD, DO, NH3-N and TPH were higher, petroleum hydrocarbons was 100%, it can be considered that the waters type of pollution was organic pollution, and petroleum hydrocarbon contamination was more prominent.展开更多
In the process of designing self-elevating drilling unit, it is important, yet complicated, to use comparison and filtering to select the optimum scheme from the feasible ones. In this research, an index system and me...In the process of designing self-elevating drilling unit, it is important, yet complicated, to use comparison and filtering to select the optimum scheme from the feasible ones. In this research, an index system and methodology for the evaluation of self-elevating drilling unit was proposed. Based on this, a multi-objective combinatorial optimization model was developed, using the improved grey relation Analysis (GRA), in which the analytic hierarchy process (AHP) was used to determine the weights of the evaluating indices. It considered the connections within the indices, reflecting the objective nature of things, and also considered the subjective interests of ship owners and the needs of designers. The evaluation index system and evaluation method can be used in the selection of an optimal scheme and advanced assessment. A case study shows the index system and evaluation method are scientific, reasonable, and easy to put into practice. At the same time, such an evaluation index system and evaluation method will be helpful for making decisions for other mobile platforms.展开更多
The development and protection of Shangri-La wetlands in southwestern Yunnan Province is of great significance for the protection of regional biodiversity, ecotourism and regional development. To specify the functions...The development and protection of Shangri-La wetlands in southwestern Yunnan Province is of great significance for the protection of regional biodiversity, ecotourism and regional development. To specify the functions of Shangri-La wetlands, with the help of Analytic Hierarchy Process (AHP), 7 typical wetlands in Shangri-La (Bita Lake Wetland, Napa Lake Wetland, Shudu Lake Wetland, Dazhongdian Wetland, Xiaozhongdian Wetland, Dahei Lake Wetland, Jinsha River Wetland) were selected for the quantitative analysis of 20 indexes in 3 comprehensive assessment layers (service functions, protective functions and production functions). The results showed that Shangri-La wetlands followed the below sequence in function: Bita Lake Wetland (0.811 4), Shudu Lake Wetland (0.739 3), Napa Lake Wetland (0.695 3), Dahei Lake Wetland (0.659 5), Jinsha River Wetland (0.614 3), Dazhongdian Wetland (0.520 4) and Xiaozhongdian Wetland (0.505 2). As single indexes of those wetlands were compared, it was found that values of certain indexes varied greatly, and value differences among 5 of 20 indexes even reached more than 100%, among which that of water supply capacity and tourism recreational value (164.60%) remained the highest, then water supplementation capacity (121.17%) and habitat stability (109.05%), and others varied between 5.58%-91.10%. The assessment results were similar to actual conditions, thus such a method was proved scientific and practical.展开更多
[Objective] The aim was to evaluate heavy metal environmental quality of irrigation water in vegetable farmlands of Shandong Province. [Method] Heavy metal contents including Hg,Cd,As,Cr (+6),Pb,Cu and Zn in irrigatio...[Objective] The aim was to evaluate heavy metal environmental quality of irrigation water in vegetable farmlands of Shandong Province. [Method] Heavy metal contents including Hg,Cd,As,Cr (+6),Pb,Cu and Zn in irrigation water of main vegetable farmlands of Shandong Province were investigated by randomly sampling,and the environmental quality conditions of these heavy metals were evaluated by methods of single quality index and complex quality index. [Result] The results showed that the average contents of heavy metals in irrigation water of Shouguang,Laiyang,Jinxiang and Zhangqiu were all far lower than the limit values prescribed by 'Farmland Environmental Quality Evaluation Standards for Edible Agricultural Products' (HJ332-2006),and no heavy metal was found beyond the limit value in every sample. The single quality indices of the 7 elements in the studied 4 places were all lower than 0.5. The comprehensive quality index of the seven elements was 0.317 8 in Shouguang,0.320 4 in Laiyang,0.232 6 in Jinxiang,and 0.260 7 in Zhangqiu. The environmental quality of irrigation water in the studied four places were all set at the first class. [Conclusion] The environmental quality of irrigation water in the 4 places belonged to clean level and were fit for the plantation of no pollution vegetables.展开更多
Non-English majors' evaluation on teachers is a vital way to get feedback of English language classroom teaching and learning. This paper reports on a study which used a discourse-analytic approach to look into the e...Non-English majors' evaluation on teachers is a vital way to get feedback of English language classroom teaching and learning. This paper reports on a study which used a discourse-analytic approach to look into the existing problems in English classroom teaching at undergraduates' level. The ways of searching solutions for the problems are also discussed.展开更多
The comprehensive carrying capacity of urban land can reflect the re- source level, economic scale, social development and environmental pressure of ur- ban land carrying. The assessment indicator system of urban land...The comprehensive carrying capacity of urban land can reflect the re- source level, economic scale, social development and environmental pressure of ur- ban land carrying. The assessment indicator system of urban land comprehensive carrying capacity was constructed from the 4 aspects of resource, economy, society, environment, and principal component analysis and cluster analysis were used to evaluate the urban land comprehensive carrying capacity of Guangxi and the 14 cities in 2005-2014, and analyzed its spatial and temporal characteristics as well as the driving forces, with the aim to provide references for improving the urban land comprehensive carrying capacity. The results showed that, the overall urban land comprehensive carrying capacity in Guangxi increased in 2005-2014, and there were significant differences in the land comprehensive carrying capacities among the cities in Guangxi in 2005-2014, in which Liuzhou, Guilin, Nanning belonged to the regions with the highest carrying capacity, while Beihai, Yulin, Wutong belonged to the regions with high carrying capacity, and the carrying capacities of the other cities changed with the changes of time. The economic development degree was an important factor influencing urban land comprehensive carrying capacity, but could not directly represent the urban land comprehensive carrying capacity level.展开更多
In order to evaluate the general situation and find special problems of the freeway incident management system, an evaluation model is proposed. First, the expert appraisal approach is used to select the primary evalu...In order to evaluate the general situation and find special problems of the freeway incident management system, an evaluation model is proposed. First, the expert appraisal approach is used to select the primary evaluation index. As a result, 81 indices and the hierarchical structures of the index such as the object layer, the sub-object layer, the criterion layer and the index layer are determined. Then, based on the fuzzy characteristics of each index layer, the analytical hierarchy process(AHP)and the fuzzy comprehensive evaluation are applied to generate the weight and the satisfaction of the index and the criterion layers. When analyzing the relationship between the sub-object layer and the object layer, it is easy to find that the number of sub-objects is too large and sub-objects are significantly redundant. The partial least square (PLS) is proposed to solve the problems. Finally, an application example, whose result has already been accepted and employed as the indication of a new project in improving incident management, is introduced and the result verifies the feasibility and efficiency of the model.展开更多
With the rapid growth of economy in China, people's living standard has been generally improved, and people's requirements on the quality and quantity of infrastructures like transportation convenience, city greenin...With the rapid growth of economy in China, people's living standard has been generally improved, and people's requirements on the quality and quantity of infrastructures like transportation convenience, city greening have become higher and higher, which requires the government to attach importance to these livelihood is- sues. Based on the China Statistical Yearbook, 6 target factors of 31 provinces and cities in China were conducted with factor analysis, and the conditions of the infras- tructures in the 31 provinces and cities were judged and evaluated through the ex- traction of common factors and the calculation of these common factors, and corre- sponding suggestions were proposed with the aim to improve the infrastructures in China.展开更多
The appearance quality, physical properties, chemical components and sensory quality of 69 flue-cured tobacco leaf samples from 6 counties of Fuzhou City in 2013 were analyzed and evaluated, and were compared with tho...The appearance quality, physical properties, chemical components and sensory quality of 69 flue-cured tobacco leaf samples from 6 counties of Fuzhou City in 2013 were analyzed and evaluated, and were compared with those in southeast area of China. The results showed that the flue-cured tobacco leaves in Fuzhou in 2013 had better hygroscopicity, toughness and filling ability, as well as suitable dragging force. However, some of the tobacco leaves were slightly thin, and had relatively high stem ratio. The tobacco leaves in Fuzhou had higher potassium content, lower starch content, and higher potassium to chlorine ratio. The middle tobacco leaves had better coordination of chemical components and general sensory quality(medium to medium-super level). Most upper and middle flue-cured tobacco leaf samples had medium-super aroma quality, relatively sufficient aroma quantity,and relatively concentrated smoke; while the lower flue-cured tobacco leaves had little aroma quantity and insufficient smoke. The appearance quality score of lower tobacco leaf samples in Fuzhou in 2013 was slightly lower than that in southeastand whole China. The scores of maturity and leaf structure of middle tobacco leaves in Fuzhou were equivalent to those in southeast China and the national averages.The upper leaves in Fuzhou obtained an equivalent score in oil content and slightly lower scores in other indexes as compared with those in southeast China.The middle-lower tobacco leaves in Fuzhou had better hygroscopicity and toughness compared with those in southeastand whole China. The total alkaloid content per plant andreducing sugar content and potassium content in the middle and lower parts were higher than those in southeast and whole China. However, the scores of coordination of chemical components of lower and upper tobacco leaves in Fuzhou were slightly lower than those in southeast and whole China. The sensory quality of the 3 parts of tobacco leaves in Fuzhou were similar to that in southeast and whole China, but the score of consistency of upper tobacco leaves in Fuzhou was slightly higher.展开更多
Wetlands in the Jianghan Plain are important components of wetland types in lake area in the middle and lower reaches the Changjiang (Yangtze) River and they fulfill many uses and functions related to hydrology, waste...Wetlands in the Jianghan Plain are important components of wetland types in lake area in the middle and lower reaches the Changjiang (Yangtze) River and they fulfill many uses and functions related to hydrology, waste assimilation, ecosystem productivity and biodiversity. Owing to natural factors and human activities, especially excessive reclamation from lakes, the shrinking process of the lakes has been accelerated. Wetland ecosystem has shown the characteristics of vulnerability. According to the analysis of wetland ecological function in the Jianghan Plain, this paper presented an index system related to productivity, stability and environmental capacity. By using the method of Analytic Hierarchy Process, we computed the values of the relative weights of the indexes, and evaluated the vulnerability level of the wetland ecosystem by the method of multi-indexes. The case study showed that the fragile extent of wetland ecosystem in the Jianghan Plain is 5.6. This means that the wetland ecosystem in the Jianghan Plain is laid to the state of middle vulnerability. Therefore, the wetland conservation and eco-rehabilitation in the Jianghan Plain should be paid attention to.展开更多
Based on the upper bound of limit analysis, the plane-strain analysis of the slopes reinforced with a row of piles to the 3D case was extended. A 3D rotational failure mechanism was adopted to yield the upper bound of...Based on the upper bound of limit analysis, the plane-strain analysis of the slopes reinforced with a row of piles to the 3D case was extended. A 3D rotational failure mechanism was adopted to yield the upper bound of the factor of safety. Parametric studies were carried out to explore the end effects of the slope failures and the effects of the pile location and diameter on the safety of the reinforced slopes. The results demonstrate that the end effects nearly have no effects on the most suitable location of the installed piles but have significant influence on the safety of the slopes. For a slope constrained to a narrow width, the slope becomes more stable owing to the contribution of the end effects. When the slope is reinforced with a row of piles in small space between piles, the effects of group piles are significant for evaluating the safety of slopes. The presented method is more appropriate for assessing the stability of slopes reinforced with piles and can be also utilized in the design of plies stabilizing the unstable slopes.展开更多
Agricultural land quality assessment of karst mountain areas is an impor-tant means to protect and manage cultivated land quality of karst mountain areas. With Jingxi County as a case, the data resources included achi...Agricultural land quality assessment of karst mountain areas is an impor-tant means to protect and manage cultivated land quality of karst mountain areas. With Jingxi County as a case, the data resources included achievements of cultivat-ed land grade, achievements of second land investigation, investigation of local con-ditions and the other data resources. With the overlay tool of MapGIS, attribute data of evaluation index were obtained, which can reflect agricultural land' characteris-tics, and agricultural land quality scores were calculated and land quality was grad-ed using the model of comprehensive evaluation of multiple factors to make further analysis on characteristics and spatial distribution. The results showed that used agricultural land is dominated by middle and high-grade lands in Jingxi County mainly, representing 68.58% of Jingxi County’s agricultural lands. On the other hand, the quality of paddy land is general y higher than that of dry land, and quality of agricultural land showed higher in middle and eastern Jingxi, and lower in north-western region, which provides references for national land management.展开更多
In order to improve the safety of the battery of satellite side mounting,and prevent the screw from producing excess due to frequent assembly and disassembly,the YS-20 material replacement and structure optimization d...In order to improve the safety of the battery of satellite side mounting,and prevent the screw from producing excess due to frequent assembly and disassembly,the YS-20 material replacement and structure optimization design of the screw body are carried out under the premise of not changing the original tooling.The double⁃shear test of YS-20 bar is carried out,and the ANSYS optimization design module is used to design 7×7×6,a total of 294,calculation cases of D1,D2,T,the three important dimension parameters of screw structure.The actual bearing state of screw composite structure is accurately simulated by using asymmetric contact model.Three comprehensive evaluations are established,and the calculation examples satisfying the conditions are evaluated comprehensively.The final results are T=12.2 mm,D1=16 mm,D2=2 mm.The stress verification and contact analysis are carried out for the final scheme and the bearing state and contact state optimized screw structure are obtained.展开更多
Due to the increasingly serious environmental pollution and destruction,especially humans' unreasonable activities,the ecological and economic system(EES) issues of Northwest region in China have attracted more an...Due to the increasingly serious environmental pollution and destruction,especially humans' unreasonable activities,the ecological and economic system(EES) issues of Northwest region in China have attracted more and more attention of the researchers.Aiming at evaluating its ecological and economic system health,a multi-objective evaluation framework called PressureState-Response(PSR) was established to describe the ecological and economic health situations.Meanwhile,an integrative set pair model combining set pair analysis(SPA) and fuzzy analytic hierarchy process(FAHP) was proposed to assess the ecological and economic system.Then the EES status of five northwest provinces(Shanxi,Gansu,Qinghai,Ningxia and Xinjiang) of Northwest region in China was evaluated during 1985 to 2009.The EES development trends of five provinces are obtained.In general,the health values of five provinces showed a rising trend.The health values of five provinces grew rapidly during 1985 to 2000.After 2000,the health values of five provinces still followed the present growth trend,but the growth is relatively smooth.The results show that the method proposed is effective for assessing the health of ecological and economic system.展开更多
基金The Soft Science Research Project of Ministry of Housing and Urban-Rural Development of China (No. 2008-k5-14)
文摘In order to provide important parameters for schedule designing, decision-making bases for transit operation management and references for passengers traveling by bus, bus transit travel time reliability is analyzed and evaluated based on automatic vehicle location (AVL) data. Based on the statistical analysis of the bus transit travel time, six indices including the coefficient of variance, the width of travel time distribution, the mean commercial speed, the congestion frequency, the planning time index and the buffer time index are proposed. Moreover, a framework for evaluating bus transit travel time reliability is constructed. Finally, a case study on a certain bus route in Suzhou is conducted. Results show that the proposed evaluation index system is simple and intuitive, and it can effectively reflect the efficiency and stability of bus operations. And a distinguishing feature of bus transit travel time reliability is the temporal pattern. It varies across different time periods.
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Supported by Resource Utilization Pattern Research of Tibet Southeastern Nature Reserve,Social science Project Tibet Department of Science and Technology~~
文摘Pai Town-Medog County Route is known as the first hiking route in China, which is a part of Tibet tourism product, as well as a business card of Linzhi tourism. The route is abundant with natural and human resources. In the research, quantitative and qualitative methods were integrated and scientific evaluation and analysis were made on tourism resources along the route according to National Standard of Classification, Investigation and Evaluation of Tourism Resources, with countermeasures proposed.
基金The National Natural Science Foundation of China(No.51377021)the Science and Technology Project of State Grid Corporation of China(No.SGTJDK00DWJS1600014)
文摘To integrate different renewable energy resources effectively in a microgrid, a configuration optimization model of a multi-energy distributed generation(DG) system and its auxiliary equipment is proposed. The model mainly consists of two parts, the determination of initial configuration schemes according to user preference and the selection of the optimal scheme. The comprehensive evaluation index(CEI), which is acquired through the analytic hierarchy process(AHP) weight calculation method, is adopted as the evaluation criterion to rank the initial schemes. The optimal scheme is obtained according to the ranking results. The proposed model takes the diversity of different equipment parameters and investment cost into consideration and can give relatively suitable and economical suggestions for system configuration.Additionally, unlike Homer Pro, the proposed model considers the complementation of different renewable energy resources, and thus the rationality of the multi-energy DG system is improved compared with the single evaluation criterion method which only considers the total cost.
基金supported by the Key Laboratory of Marine Oil Spill Identification and Damage Assessment Technology, State Oceanic Administration (201214)
文摘Selecting six indexs of pH, DO, COD, BOD5, ammonia nitrogen and petroleum hydrocarbons in Haihe River Basin of four seasons in 2012 - 2013 for factor analysis, appling Water Quality Pollution Index (API) to evaluate DO, COD, BOD5 and ammonia nitrogen, aims for systematic evluation to water quality of Haihe River Basin The results showed that two stations of B J1 and HB2 were the 1V type of water, others were the V type; Water Quality Pollution Index (API) was 1.44, which illustrated Haihe River Basin in the state of contamination that the degree of pollution exceeded the standard of functional areas. Factor Analysis explained that between COD, DO and NH3-N were significant difference (P〈0.05); principal component analysis showed that, in addition to pH and BOD5, the other indicators were above 0.70; the contribution rate of COD, DO, NH3-N and TPH were higher, petroleum hydrocarbons was 100%, it can be considered that the waters type of pollution was organic pollution, and petroleum hydrocarbon contamination was more prominent.
基金Supported by the National 863 Plan Foundation under Grant No.2003AA414060
文摘In the process of designing self-elevating drilling unit, it is important, yet complicated, to use comparison and filtering to select the optimum scheme from the feasible ones. In this research, an index system and methodology for the evaluation of self-elevating drilling unit was proposed. Based on this, a multi-objective combinatorial optimization model was developed, using the improved grey relation Analysis (GRA), in which the analytic hierarchy process (AHP) was used to determine the weights of the evaluating indices. It considered the connections within the indices, reflecting the objective nature of things, and also considered the subjective interests of ship owners and the needs of designers. The evaluation index system and evaluation method can be used in the selection of an optimal scheme and advanced assessment. A case study shows the index system and evaluation method are scientific, reasonable, and easy to put into practice. At the same time, such an evaluation index system and evaluation method will be helpful for making decisions for other mobile platforms.
基金Supported by National Natural Science Foundation of China(40861009)Provincial Natural Science Foundation of Yunnan(2002D0036M)~~
文摘The development and protection of Shangri-La wetlands in southwestern Yunnan Province is of great significance for the protection of regional biodiversity, ecotourism and regional development. To specify the functions of Shangri-La wetlands, with the help of Analytic Hierarchy Process (AHP), 7 typical wetlands in Shangri-La (Bita Lake Wetland, Napa Lake Wetland, Shudu Lake Wetland, Dazhongdian Wetland, Xiaozhongdian Wetland, Dahei Lake Wetland, Jinsha River Wetland) were selected for the quantitative analysis of 20 indexes in 3 comprehensive assessment layers (service functions, protective functions and production functions). The results showed that Shangri-La wetlands followed the below sequence in function: Bita Lake Wetland (0.811 4), Shudu Lake Wetland (0.739 3), Napa Lake Wetland (0.695 3), Dahei Lake Wetland (0.659 5), Jinsha River Wetland (0.614 3), Dazhongdian Wetland (0.520 4) and Xiaozhongdian Wetland (0.505 2). As single indexes of those wetlands were compared, it was found that values of certain indexes varied greatly, and value differences among 5 of 20 indexes even reached more than 100%, among which that of water supply capacity and tourism recreational value (164.60%) remained the highest, then water supplementation capacity (121.17%) and habitat stability (109.05%), and others varied between 5.58%-91.10%. The assessment results were similar to actual conditions, thus such a method was proved scientific and practical.
基金Supported by National Science and Technology Project of "the Eleventh Five-year Plan" of China (2006BAD17B07)Doctoral Fund of Shandong Academy of Agricultural Sciences (2006YBS015)~~
文摘[Objective] The aim was to evaluate heavy metal environmental quality of irrigation water in vegetable farmlands of Shandong Province. [Method] Heavy metal contents including Hg,Cd,As,Cr (+6),Pb,Cu and Zn in irrigation water of main vegetable farmlands of Shandong Province were investigated by randomly sampling,and the environmental quality conditions of these heavy metals were evaluated by methods of single quality index and complex quality index. [Result] The results showed that the average contents of heavy metals in irrigation water of Shouguang,Laiyang,Jinxiang and Zhangqiu were all far lower than the limit values prescribed by 'Farmland Environmental Quality Evaluation Standards for Edible Agricultural Products' (HJ332-2006),and no heavy metal was found beyond the limit value in every sample. The single quality indices of the 7 elements in the studied 4 places were all lower than 0.5. The comprehensive quality index of the seven elements was 0.317 8 in Shouguang,0.320 4 in Laiyang,0.232 6 in Jinxiang,and 0.260 7 in Zhangqiu. The environmental quality of irrigation water in the studied four places were all set at the first class. [Conclusion] The environmental quality of irrigation water in the 4 places belonged to clean level and were fit for the plantation of no pollution vegetables.
文摘Non-English majors' evaluation on teachers is a vital way to get feedback of English language classroom teaching and learning. This paper reports on a study which used a discourse-analytic approach to look into the existing problems in English classroom teaching at undergraduates' level. The ways of searching solutions for the problems are also discussed.
基金Supported by the Open Bidding Projects of the Office of Land and Resources of the Guangxi Zhuang Autonomous Region(GXZC2015-G3-0575-GTZB)~~
文摘The comprehensive carrying capacity of urban land can reflect the re- source level, economic scale, social development and environmental pressure of ur- ban land carrying. The assessment indicator system of urban land comprehensive carrying capacity was constructed from the 4 aspects of resource, economy, society, environment, and principal component analysis and cluster analysis were used to evaluate the urban land comprehensive carrying capacity of Guangxi and the 14 cities in 2005-2014, and analyzed its spatial and temporal characteristics as well as the driving forces, with the aim to provide references for improving the urban land comprehensive carrying capacity. The results showed that, the overall urban land comprehensive carrying capacity in Guangxi increased in 2005-2014, and there were significant differences in the land comprehensive carrying capacities among the cities in Guangxi in 2005-2014, in which Liuzhou, Guilin, Nanning belonged to the regions with the highest carrying capacity, while Beihai, Yulin, Wutong belonged to the regions with high carrying capacity, and the carrying capacities of the other cities changed with the changes of time. The economic development degree was an important factor influencing urban land comprehensive carrying capacity, but could not directly represent the urban land comprehensive carrying capacity level.
文摘In order to evaluate the general situation and find special problems of the freeway incident management system, an evaluation model is proposed. First, the expert appraisal approach is used to select the primary evaluation index. As a result, 81 indices and the hierarchical structures of the index such as the object layer, the sub-object layer, the criterion layer and the index layer are determined. Then, based on the fuzzy characteristics of each index layer, the analytical hierarchy process(AHP)and the fuzzy comprehensive evaluation are applied to generate the weight and the satisfaction of the index and the criterion layers. When analyzing the relationship between the sub-object layer and the object layer, it is easy to find that the number of sub-objects is too large and sub-objects are significantly redundant. The partial least square (PLS) is proposed to solve the problems. Finally, an application example, whose result has already been accepted and employed as the indication of a new project in improving incident management, is introduced and the result verifies the feasibility and efficiency of the model.
文摘With the rapid growth of economy in China, people's living standard has been generally improved, and people's requirements on the quality and quantity of infrastructures like transportation convenience, city greening have become higher and higher, which requires the government to attach importance to these livelihood is- sues. Based on the China Statistical Yearbook, 6 target factors of 31 provinces and cities in China were conducted with factor analysis, and the conditions of the infras- tructures in the 31 provinces and cities were judged and evaluated through the ex- traction of common factors and the calculation of these common factors, and corre- sponding suggestions were proposed with the aim to improve the infrastructures in China.
基金Supported by Science and Technology Plan Project of Jiangxi Provincial Tobacco Company(201301009)~~
文摘The appearance quality, physical properties, chemical components and sensory quality of 69 flue-cured tobacco leaf samples from 6 counties of Fuzhou City in 2013 were analyzed and evaluated, and were compared with those in southeast area of China. The results showed that the flue-cured tobacco leaves in Fuzhou in 2013 had better hygroscopicity, toughness and filling ability, as well as suitable dragging force. However, some of the tobacco leaves were slightly thin, and had relatively high stem ratio. The tobacco leaves in Fuzhou had higher potassium content, lower starch content, and higher potassium to chlorine ratio. The middle tobacco leaves had better coordination of chemical components and general sensory quality(medium to medium-super level). Most upper and middle flue-cured tobacco leaf samples had medium-super aroma quality, relatively sufficient aroma quantity,and relatively concentrated smoke; while the lower flue-cured tobacco leaves had little aroma quantity and insufficient smoke. The appearance quality score of lower tobacco leaf samples in Fuzhou in 2013 was slightly lower than that in southeastand whole China. The scores of maturity and leaf structure of middle tobacco leaves in Fuzhou were equivalent to those in southeast China and the national averages.The upper leaves in Fuzhou obtained an equivalent score in oil content and slightly lower scores in other indexes as compared with those in southeast China.The middle-lower tobacco leaves in Fuzhou had better hygroscopicity and toughness compared with those in southeastand whole China. The total alkaloid content per plant andreducing sugar content and potassium content in the middle and lower parts were higher than those in southeast and whole China. However, the scores of coordination of chemical components of lower and upper tobacco leaves in Fuzhou were slightly lower than those in southeast and whole China. The sensory quality of the 3 parts of tobacco leaves in Fuzhou were similar to that in southeast and whole China, but the score of consistency of upper tobacco leaves in Fuzhou was slightly higher.
文摘Wetlands in the Jianghan Plain are important components of wetland types in lake area in the middle and lower reaches the Changjiang (Yangtze) River and they fulfill many uses and functions related to hydrology, waste assimilation, ecosystem productivity and biodiversity. Owing to natural factors and human activities, especially excessive reclamation from lakes, the shrinking process of the lakes has been accelerated. Wetland ecosystem has shown the characteristics of vulnerability. According to the analysis of wetland ecological function in the Jianghan Plain, this paper presented an index system related to productivity, stability and environmental capacity. By using the method of Analytic Hierarchy Process, we computed the values of the relative weights of the indexes, and evaluated the vulnerability level of the wetland ecosystem by the method of multi-indexes. The case study showed that the fragile extent of wetland ecosystem in the Jianghan Plain is 5.6. This means that the wetland ecosystem in the Jianghan Plain is laid to the state of middle vulnerability. Therefore, the wetland conservation and eco-rehabilitation in the Jianghan Plain should be paid attention to.
基金Projects(51278382,51479050)supported by the National Natural Science Foundation of ChinaProject(2015CB057901)supported by the National Key Basic Research Program of China+3 种基金Project(201501035-03)supported by the Public Service Sector R&D Project of Ministry of Water Resource of ChinaProject(2014B06814)supported by the Fundamental Research Funds for the Central Universities,ChinaProject(B13024)supported by the"111"ProjectProject(YK913004)supported by the Open Foundation of Key Laboratory of Failure Mechanism and Safety Control Techniques of Earthrock Dam of the Ministry of Water Resources,China
文摘Based on the upper bound of limit analysis, the plane-strain analysis of the slopes reinforced with a row of piles to the 3D case was extended. A 3D rotational failure mechanism was adopted to yield the upper bound of the factor of safety. Parametric studies were carried out to explore the end effects of the slope failures and the effects of the pile location and diameter on the safety of the reinforced slopes. The results demonstrate that the end effects nearly have no effects on the most suitable location of the installed piles but have significant influence on the safety of the slopes. For a slope constrained to a narrow width, the slope becomes more stable owing to the contribution of the end effects. When the slope is reinforced with a row of piles in small space between piles, the effects of group piles are significant for evaluating the safety of slopes. The presented method is more appropriate for assessing the stability of slopes reinforced with piles and can be also utilized in the design of plies stabilizing the unstable slopes.
基金Supported by Supplemented Project of Guangxi Zhuang Autonomous Region Agricultural Land Quality Grade Achievements(GXKLJ20133073-E)~~
文摘Agricultural land quality assessment of karst mountain areas is an impor-tant means to protect and manage cultivated land quality of karst mountain areas. With Jingxi County as a case, the data resources included achievements of cultivat-ed land grade, achievements of second land investigation, investigation of local con-ditions and the other data resources. With the overlay tool of MapGIS, attribute data of evaluation index were obtained, which can reflect agricultural land' characteris-tics, and agricultural land quality scores were calculated and land quality was grad-ed using the model of comprehensive evaluation of multiple factors to make further analysis on characteristics and spatial distribution. The results showed that used agricultural land is dominated by middle and high-grade lands in Jingxi County mainly, representing 68.58% of Jingxi County’s agricultural lands. On the other hand, the quality of paddy land is general y higher than that of dry land, and quality of agricultural land showed higher in middle and eastern Jingxi, and lower in north-western region, which provides references for national land management.
文摘In order to improve the safety of the battery of satellite side mounting,and prevent the screw from producing excess due to frequent assembly and disassembly,the YS-20 material replacement and structure optimization design of the screw body are carried out under the premise of not changing the original tooling.The double⁃shear test of YS-20 bar is carried out,and the ANSYS optimization design module is used to design 7×7×6,a total of 294,calculation cases of D1,D2,T,the three important dimension parameters of screw structure.The actual bearing state of screw composite structure is accurately simulated by using asymmetric contact model.Three comprehensive evaluations are established,and the calculation examples satisfying the conditions are evaluated comprehensively.The final results are T=12.2 mm,D1=16 mm,D2=2 mm.The stress verification and contact analysis are carried out for the final scheme and the bearing state and contact state optimized screw structure are obtained.
基金supported in partially by the National Society Science Fund of China(Grant No.09CJY020)the Special Fund of State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering,China(Grant No. 2011585312)+1 种基金the Fundamental Research Funds for the Central Universities of Hohai University2010 Jiangsu Province Qing Lan Project
文摘Due to the increasingly serious environmental pollution and destruction,especially humans' unreasonable activities,the ecological and economic system(EES) issues of Northwest region in China have attracted more and more attention of the researchers.Aiming at evaluating its ecological and economic system health,a multi-objective evaluation framework called PressureState-Response(PSR) was established to describe the ecological and economic health situations.Meanwhile,an integrative set pair model combining set pair analysis(SPA) and fuzzy analytic hierarchy process(FAHP) was proposed to assess the ecological and economic system.Then the EES status of five northwest provinces(Shanxi,Gansu,Qinghai,Ningxia and Xinjiang) of Northwest region in China was evaluated during 1985 to 2009.The EES development trends of five provinces are obtained.In general,the health values of five provinces showed a rising trend.The health values of five provinces grew rapidly during 1985 to 2000.After 2000,the health values of five provinces still followed the present growth trend,but the growth is relatively smooth.The results show that the method proposed is effective for assessing the health of ecological and economic system.