According to the description effect range, the method of scaling system in cartography is with the precision of four grades： nominal scaling, ordinal scaling, interval scaling and ratio scaling. The authors have rese...According to the description effect range, the method of scaling system in cartography is with the precision of four grades： nominal scaling, ordinal scaling, interval scaling and ratio scaling. The authors have researched their innate character and inherent relations. The essence of evaluation partialordering set （A ,≤） is the mapping of evaluation object （X, ≤） under fixed condition. The collection and classification of xi ∈ X corresponds how to express Aj ∈ A, i.e. , V xi ∈ X→f（xi ） = Aj → A, Aj is the image of xi under mapping f. The function relation between evaluation partial-ordering set （A, ≤） and evaluation object （X, ≤） is decided by the space character and the way of collection and classification. The different space character and way of collection and classification will produce the different express method and evaluation result, accordingly the authors give out the mathematical definitions for nominal scaling, ordinal scaling, interval scaling and ratio scaling respectively. These results have been proved through the examples.展开更多
In this paper the Auerbach＇s scaling law of Hertzian fracture induced by a spherical indenter pressing on a brittle solid is studied. In the analysis, the singular integral equation method is used to analyze the frac...In this paper the Auerbach＇s scaling law of Hertzian fracture induced by a spherical indenter pressing on a brittle solid is studied. In the analysis, the singular integral equation method is used to analyze the fracture behavior of the Hertzian contact problem. The results show that the Auerbach＇s constant sensitively depends on the Poisson＇s ratio, and the effective Auerbach＇s domain is also determined for a given value of the Poisson＇s ratio.展开更多
Iraq faces water scarcity due to a shortage of surface water resources. People in Safwan (Basrah, Iraq) and its environs use brackish groundwater as alternative resource. To improve water quality, small reverse osmosi...Iraq faces water scarcity due to a shortage of surface water resources. People in Safwan (Basrah, Iraq) and its environs use brackish groundwater as alternative resource. To improve water quality, small reverse osmosis (RO) plants have been established. The water selling price is (1.3 $/m<sup>3</sup>)* which does not cover the product cost which is (2.4 $/m<sup>3</sup>)*. Data were collected from eight plants, and a techno-economic assessment was conducted to explore the ideal cost. The known effective factored considered in this case, recovery ratio, temperature and total dissolved solids (TDS). From the other side, membrane replacement and energy cost were significantly effect, when their portions of the total production cost were 30.98%* and 48.38%* respectively as shown in Figure 10. In addition, software analysis was used to predict the scaling potential in raw water samples. Its results showed a high inorganic fouling (scaling) potential. Scaling has a permanent influence on operations and maintenance costs. These identified major cost influencers will be incorporated into the experimental design of the next phase of this ongoing research programme.展开更多
Plant community structure responds strongly to anthropogenic disturbances, which greatly influence community stability. The changes in community structure, aboveground biomass（AGB）, biodiversity and community stabil...Plant community structure responds strongly to anthropogenic disturbances, which greatly influence community stability. The changes in community structure, aboveground biomass（AGB）, biodiversity and community stability associated with different management practices were studied with a three-year field investigation in a temperate steppe of Inner Mongolia, China. The species richness, Shannon-Wiener index, evenness, plant functional type abundance, AGB, temporal community stability, summed covariance, scaling coefficient and dominant species stability were compared among areas subjected to long-term reservation（R）, long-term grazing（G）, mowing since enclosure in 2008（M） and grazing enclosure since 2008（E）. Site R had higher perennial grass abundance and lower species richness than sites G, M and E, although the AGB was not significantly different among the four sites. The species structure varied from a single dominant species at site R to multiple dominant species at sites G, M and E. The long-term reservation grassland had lower biodiversity but higher stability, whereas the enclosed grassland with/without mowing had higher biodiversity but lower stability. Different stability mechanisms, such as the compensatory dynamics, mean-variance scaling and dominant species stability were examined. Results showed that community stability was most closely related to the relative stability of the dominant species, which supports the biomass ratio hypothesis proposed by Grime.展开更多
文摘According to the description effect range, the method of scaling system in cartography is with the precision of four grades： nominal scaling, ordinal scaling, interval scaling and ratio scaling. The authors have researched their innate character and inherent relations. The essence of evaluation partialordering set （A ,≤） is the mapping of evaluation object （X, ≤） under fixed condition. The collection and classification of xi ∈ X corresponds how to express Aj ∈ A, i.e. , V xi ∈ X→f（xi ） = Aj → A, Aj is the image of xi under mapping f. The function relation between evaluation partial-ordering set （A, ≤） and evaluation object （X, ≤） is decided by the space character and the way of collection and classification. The different space character and way of collection and classification will produce the different express method and evaluation result, accordingly the authors give out the mathematical definitions for nominal scaling, ordinal scaling, interval scaling and ratio scaling respectively. These results have been proved through the examples.
基金supported by the National Natural Science Foundation of China(No.10772058)
文摘In this paper the Auerbach＇s scaling law of Hertzian fracture induced by a spherical indenter pressing on a brittle solid is studied. In the analysis, the singular integral equation method is used to analyze the fracture behavior of the Hertzian contact problem. The results show that the Auerbach＇s constant sensitively depends on the Poisson＇s ratio, and the effective Auerbach＇s domain is also determined for a given value of the Poisson＇s ratio.
文摘Iraq faces water scarcity due to a shortage of surface water resources. People in Safwan (Basrah, Iraq) and its environs use brackish groundwater as alternative resource. To improve water quality, small reverse osmosis (RO) plants have been established. The water selling price is (1.3 $/m<sup>3</sup>)* which does not cover the product cost which is (2.4 $/m<sup>3</sup>)*. Data were collected from eight plants, and a techno-economic assessment was conducted to explore the ideal cost. The known effective factored considered in this case, recovery ratio, temperature and total dissolved solids (TDS). From the other side, membrane replacement and energy cost were significantly effect, when their portions of the total production cost were 30.98%* and 48.38%* respectively as shown in Figure 10. In addition, software analysis was used to predict the scaling potential in raw water samples. Its results showed a high inorganic fouling (scaling) potential. Scaling has a permanent influence on operations and maintenance costs. These identified major cost influencers will be incorporated into the experimental design of the next phase of this ongoing research programme.
基金funded by the National Natural Science Foundation of China (41030535, 41371069)the Fundamental Research Funds for the Central Universitiesthe Program for Changjiang Scholars and Innovative Research Team in University (IRT1108)
文摘Plant community structure responds strongly to anthropogenic disturbances, which greatly influence community stability. The changes in community structure, aboveground biomass（AGB）, biodiversity and community stability associated with different management practices were studied with a three-year field investigation in a temperate steppe of Inner Mongolia, China. The species richness, Shannon-Wiener index, evenness, plant functional type abundance, AGB, temporal community stability, summed covariance, scaling coefficient and dominant species stability were compared among areas subjected to long-term reservation（R）, long-term grazing（G）, mowing since enclosure in 2008（M） and grazing enclosure since 2008（E）. Site R had higher perennial grass abundance and lower species richness than sites G, M and E, although the AGB was not significantly different among the four sites. The species structure varied from a single dominant species at site R to multiple dominant species at sites G, M and E. The long-term reservation grassland had lower biodiversity but higher stability, whereas the enclosed grassland with/without mowing had higher biodiversity but lower stability. Different stability mechanisms, such as the compensatory dynamics, mean-variance scaling and dominant species stability were examined. Results showed that community stability was most closely related to the relative stability of the dominant species, which supports the biomass ratio hypothesis proposed by Grime.
