The policy of land transfer has greatly influenced the macro economy of China with the commencement of another innovation of land use system. Therefore, it is urgent to put forward some rational and feasible suggestio...The policy of land transfer has greatly influenced the macro economy of China with the commencement of another innovation of land use system. Therefore, it is urgent to put forward some rational and feasible suggestions for local government to manage the market of land transfer. Moreover, it is important in the field of study on agricultural land use change to analyze the spatial differentiation and structural specification of land transfer, which are caused by rural households' behavior. This paper selected I l factors covering four aspects of rural households' family structure, family location, family income structure and the natural quality of land resources, all of which influence the behavior differentiation of rural households, to establish the index model indicating spatial differentiation of land transfer. Results show that the spatial differentiation of land transfer can be divided into four degrees and three categories through analyzing rural households' questionnaires from Shanghai, Nanjing and Taizhou in the Changjiang (Yangtze) River Delta. Since up to 80% of rural households belong to middle degrees, it can be concluded that the rural land market develops evenly in the study areas. And it is also indicated that the natural quality of land resources and the maximum income of rural land are most important factors influencing the spatial differentiation of land transaction. Considering different factors, the countermeasures can be carried out to enhance the spatial differentiation of land transfer so as to promote economic development and social security of rural China. All in all, both micro- factors and macro-factors influencing rural households' behavior of rural land transfer should be taken into account in order to make spatial differentiation and structural specification of rural land transfer notable.展开更多
The objectives of this study are to assess land s ui tability and to predict the spatial and temporal changes in land use types (LUTs ) by using GIS-based land use management decision support system. A GIS databas e w...The objectives of this study are to assess land s ui tability and to predict the spatial and temporal changes in land use types (LUTs ) by using GIS-based land use management decision support system. A GIS databas e with data on climate, topography, soil characteristic, irrigation condition, f ertilizer application, and special socioeconomic activities has been developed a nd used for the evaluation of land productivity for different crops by integrati ng with a crop growth model-the erosion productivity impact calculator (EPIC). International food policy simulation model (IFPSIM) is also embedded into GIS fo r the predictions of how crop demands and crop market prices will change under a lternative policy scenarios. An inference engine (IE) including land use choice model is developed to illustrate land use choice behavior based on logit models , which allows to analyze how diversified factors ranging from climate changes, crop price changes to land management changes can affect the distribution of agr icultural land use. A test for integrated simulation is taken in each 0.1° by 0.1° grid cell to predict the change of agricultural land use types at globa l level. Global land use changes are simulated from 1992 to 2050.展开更多
As an important part of land use/cover change(LUCC), historical LUCC in long time series attracts much more attention from scholars. Currently, based on the view of combining the overall control of cropland area and ...As an important part of land use/cover change(LUCC), historical LUCC in long time series attracts much more attention from scholars. Currently, based on the view of combining the overall control of cropland area and ′top-down′ decision-making behaviors, here are two global historical land-use datasets, generally referred as the Sustainability and the Global Environment datasets(SAGE datasets) and History Database of the Global Environment datasets(HYDE datasets). However, at the regional level, these global datasets have coarse resolutions and inevitable errors. Considering various factors that influenced cropland distribution, including cropland connectivity and the limitation of natural and human factors, this study developed a reconstruction model of historical cropland based on constrained Cellular Automaton(CA) of ′bottom-up′. Then, an available labor force index is used as a proxy for the amount of cropland to inspect and calibrate these spatial patterns. Applied the reconstruction model to Shandong Province, we reconstructed its spatial distribution of cropland during 8 periods. The reconstructed results show that: 1) it is properly suitable for constrained CA to simulate and reconstruct the spatial distribution of cropland in traditional cultivated region of China; 2) compared with ′SAGE datasets′ and ′HYDE datasets′, this study have formed higher-resolution Boolean spatial distribution datasets of historical cropland with a more definitive concept of spatial pattern in terms of fractional format.展开更多
Forest fire is one of the major causes of forest loss and therefore one of the main constraints for sustainable forest management worldwide.Identifying the driving factors and understanding the contribution of each fa...Forest fire is one of the major causes of forest loss and therefore one of the main constraints for sustainable forest management worldwide.Identifying the driving factors and understanding the contribution of each factor are essential for the management of forest fire occurrence.The objective of this study is to identify variables that are spatially related to the occurrence and incidence of the forest fire in the State of Durango,Mexico.For this purpose,data from forest fire records for a five-year period were analyzed.The spatial correlations between forest fire occurrence and intensity of land use,susceptibility of vegetation,temperature,precipitation and slope were tested by Geographically Weighted Regression(GWR) method,under an Ordinary Least Square estimator.Results show that the spatial pattern of the forest fire in the study area is closely correlated with the intensity of land use,and land use change is one of the main explanatory variables.In addition,vegetation type and precipitation are also the main driving factors.The fitting model indicates obvious link between the variables.Forest fire was found to be the consequence of a particular combination of the environmental factors,and when these factors coexist with human activities,there is high probability of forest fire occurrence.Mandatory regulation of human activities is a key strategy for forest fire prevention.展开更多
In this paper, another form of KKM type theorem on generalized convex spaces is obtained and the problems of von Neumann-Fan type sup inf sup inequalities and variational inequalities are discussed for their applicati...In this paper, another form of KKM type theorem on generalized convex spaces is obtained and the problems of von Neumann-Fan type sup inf sup inequalities and variational inequalities are discussed for their applications.The main results improve and generalize the corresponding results in previous papers.展开更多
In this paper we report on recent development in the areas of optical vortices generated by micro-optical elements and applications of optical vortices, including optical manipulation, radial polarization and secure f...In this paper we report on recent development in the areas of optical vortices generated by micro-optical elements and applications of optical vortices, including optical manipulation, radial polarization and secure free space optical communication展开更多
Nowadays, about 80% of the Danube floodplain--Romanian sector are embanked and arranged with desiccation works and locally with drainage. Once with increasing pressures on the system and the complexity of the issues, ...Nowadays, about 80% of the Danube floodplain--Romanian sector are embanked and arranged with desiccation works and locally with drainage. Once with increasing pressures on the system and the complexity of the issues, there has been developed a number of mechanisms by which human activity (LU change) influence the stability and services of ecosystems and the need for planning tools are changing rapidly. Motivated by dramatic climatic change in recent decades and especially increased frequency of extreme events--2006 and 2010, the study focused on developing models and scenarios of climatic change, especially those related to land use change and flooding affecting local communities/regions. Thus, in the given circumstances, the best option is to foreseen a policy on the Lower Danube riverbed, followed by a series of advanced tools for exploring the 4D reconnection (longitudinal, lateral, vertical and temporal) and a well prepared monitoring system which alert address to detected threats. 4D reconnection of the lower Danube floodplain will provide a spatial planning tool, developed in accordance with this three features, and built to design, analyse and evaluate long-term policies in an ecological, social, economic and cultural context.展开更多
In Tokyo, as residential areas exist in the urban areas and are composed of areas owned by individual land owners, basically spatial changes are brought by redevelopments of each sites conducted by individual circumst...In Tokyo, as residential areas exist in the urban areas and are composed of areas owned by individual land owners, basically spatial changes are brought by redevelopments of each sites conducted by individual circumstances and motivations. Continuous redevelopments and spatial changes can be found dispersedly in areas. Once the spatial change in a certain site occurred in an area as a building, it will be contained in the built environment of the residential area which is defined by residents, planners and designers who will take part in the following spatial changes. In Tokyo, public transportation facilities are well developed, and residents' daily life involves activities such as a slow walking and bicycle, etc. around the place of residence near the public transportation hubs, each living territories are formed in this kind of manner. Considering the maintenance of spatial value in residential areas while understanding transformation of visual local environment in residential areas which focuses on appearance of each spatial change in an area of street will be of significant importance. In this paper, the authors try to describe interactions of spatial changes in existing urban residential areas focusing on utility of players who might take part in the following spatial changes and the method of discrete choice model.展开更多
This study aims to analyze spatial landuse and farming system of reclamated tidal lowland in South Sumatra, Indonesia by using remote sensing technology and GIS in knowing the distribution of landuse change of tidal l...This study aims to analyze spatial landuse and farming system of reclamated tidal lowland in South Sumatra, Indonesia by using remote sensing technology and GIS in knowing the distribution of landuse change of tidal lowland. From these conditions, it can see cropping patterns on each of the secondary block and its relation to the condition of the water system network. The study was carried out in Delta Saleh areas. The used methodology was field survey and remote sensing technique. It was combined with GIS technology for spatial analysis. Over the last 11 years (1992-2002), a decline in the paddy field area is from 23,619.4 ha to 18,518.40 ha (27.65%). A decrease of river acreage (water body) occurred from 6,643.53 ha to 6,559.83 ha. In 1992 it has not detected any coconut plantation, while in 2001 it showed an area of coconut plantation 3,422.84 ha and 3,822.84 ha in 20l l. Significant changes are also presented in primary mangrove forest, widespread declining around 1,940.88 ha (147.20%). Most of the mangrove forest was converted into secondary mangrove forest and scrub. Linkage with topography type showed that the land with topography Type A was majority for paddy fields 250.28-262.80 ha (62.72%-65.59%). Mixed crop fields were in second place with acreage of 90.66-107.36 ha (22.72%-26.80%). The land with topography Type B showed the widest paddy fields (283.14-314.20 ha or 70.70%-78.48%), followed by upland crops. The land with topography Type C showed that paddy fields were 283.03-300.41 ha (70.66%-75.02 %), followed by upland crops 94.85-102.78 ha (23.69%-25.66%), and coconut was the smallest 0.09-0.27 ha. Generally, the cropping index was 100 on PS-I (planting season 1) for BL-I (business land 1) and BL-2 planted with paddy fields, while the PS-2 are generally not cultivated land (fallow).展开更多
Knowledge and management of soil pH, particularly soil acidity across spatially variable soils is important, although this is greatly ignored by farmers. The objective of the study was to evaluate in-field spatial var...Knowledge and management of soil pH, particularly soil acidity across spatially variable soils is important, although this is greatly ignored by farmers. The objective of the study was to evaluate in-field spatial variability of soil pH, and compare the efficiency of managing soil pH through site-specific method vs. uniform lime application. The study was conducted on three sites with study sites I and II (23°50' S; 29°40' E), and study sites IIl (23°59' S; 28°52' E) adjacent to each other in the semi-arid regions of the Limpopo Province, South Africa. Soil samples were taken in four replicates from geo-referenced locations on a regular grid of 30 m. Soils were analyzed for pH, and SMP buffer pH. Soil maps were produced with Geographic Information System (GIS) software, and soil pH datasets were interpolated using a geostatistical tool of inverse distance weighing (IDW). Soil pH in the fields varied from 3.93 to 7.00. An excess amount of lime as high as 30 t/ha under uniform lime application were recorded. These recommendations were in excess on field areas that needed little or no lime applications. Again, there was an under applications of lime as much as 35 t/ha for uniform liming applications. This under- and over-recommendations of lime based on average soil pH values suggests that uniform soil acidity correction and soil pH management strategy is not an appropriate strategy to be adopted in these fields with spatially variable soils. The field can be divided into lime application zones of (1) high rates of lime, (2) low rates of lime and (3) areas that requires no lime at all so that lime rates are applied per zone. A key to site-specific soil acidity correction with lime is to reach ideal soil pH for the crop in all parts of the field.展开更多
The term geopoetics has a wide interpretation. It is defined as a project of the cultural activity aimed at creating and changing territorial myths and research path, which considers the interaction between literary c...The term geopoetics has a wide interpretation. It is defined as a project of the cultural activity aimed at creating and changing territorial myths and research path, which considers the interaction between literary creativity and geographical space. Defining this term, it is possible to introduce a geopoetical analysis diagram based on three interconnected positions: the writer's personality, the universe of an artwork and its characters. The Last Novik--A historical novel by Lazhechnikov analysis example presented on a diagram reveals the relationship between time and space in the literary work, as well as the author's interaction with the described events.展开更多
Intensity of cavitation is significant in ultrasonic wastewater treatment,but is complicated to measure.A time difference based method of ultrasonic cavitation measurement is proposed.The time differences at different...Intensity of cavitation is significant in ultrasonic wastewater treatment,but is complicated to measure.A time difference based method of ultrasonic cavitation measurement is proposed.The time differences at different powers of 495 kHz ultrasonic are measured in experiment in comparison with conductimetric method.Simulation results show that time difference and electrical conductivity are both approximately positive proportional to the ultrasonic power.The degradation of PNP solution verifies the availability in wastewater treatment by using ultrasonic.展开更多
The doors and windows are the throat of the building. This paper discusses the fundamental role of the doors and windows of the building, and the dominant roles such as spatial organization and control of light, and t...The doors and windows are the throat of the building. This paper discusses the fundamental role of the doors and windows of the building, and the dominant roles such as spatial organization and control of light, and to study the recessive function of windows and doors from aspects of the psychological impact, cultural significance and decoration. After exploring the characteristics of modem windows and doors, it studies the design elements of modem windows and doors and summed up the features that the initiative to make use of the environment. Basic from three levels as the basic form of design; windows and buildings, and the social and natural environment of the unified design; doors and windows to take the initiative to study the nature.展开更多
Let X be an RD-space. In this paper, the authors establish the boundedness of the commutator Tbf = bTf-T(bf) on Lp , p∈(1,∞), where T is a Calderón-Zygmund operator related to the admissible function ρ and b∈...Let X be an RD-space. In this paper, the authors establish the boundedness of the commutator Tbf = bTf-T(bf) on Lp , p∈(1,∞), where T is a Calderón-Zygmund operator related to the admissible function ρ and b∈BMOθ(X)BMO(X). Moreover, they prove that Tb is bounded from the Hardy space H1ρ(X) into the weak Lebesgue space L1weak(X). This can be used to deal with the Schrdinger operators and Schrdinger type operators on the Euclidean space Rn and the sub-Laplace Schrdinger operators on the stratified Lie group G.展开更多
The invariant subspace method is refined to present more unity and more diversity of exact solutions to evolution equations. The key idea is to take subspaces of solutions to linear ordinary differential equations as ...The invariant subspace method is refined to present more unity and more diversity of exact solutions to evolution equations. The key idea is to take subspaces of solutions to linear ordinary differential equations as invariant subspaces that evolution equations admit. A two-component nonlinear system of dissipative equations is analyzed to shed light oi1 the resulting theory, and two concrete examples are given to find invariant subspaces associated with 2nd-order and 3rd-order linear ordinary differentii equations and their corresponding exact solutions with generalized separated variables.展开更多
Land use projections are crucial for climate models to forecast the impacts of land use changes on the Earth’s system.However,the spatial resolution of existing global land use projections(e.g.,0.25°×0.25...Land use projections are crucial for climate models to forecast the impacts of land use changes on the Earth’s system.However,the spatial resolution of existing global land use projections(e.g.,0.25°×0.25°in the Land-Use Harmonization(LUH2)datasets)is still too coarse to drive regional climate models and assess mitigation effectiveness at regional and local scales.To generate a high-resolution land use product with the newest integrated scenarios of the shared socioeconomic pathways and the representative concentration pathways(SSPs-RCPs)for various regional climate studies in China,here we first conduct land use simulations with a newly developed Future Land Uses Simulation(FLUS)model based on the trajectories of land use demands extracted from the LUH2 datasets.On this basis,a new set of land use projections under the plant functional type(PFT)classification,with a temporal resolution of 5 years and a spatial resolution of 5 km,in eight SSP-RCP scenarios from 2015 to 2100 in China is produced.The results show that differences in land use dynamics under different SSP-RCP scenarios are jointly affected by global assumptions and national policies.Furthermore,with improved spatial resolution,the data produced in this study can sufficiently describe the details of land use distribution and better capture the spatial heterogeneity of different land use types at the regional scale.We highlight that these new land use projections at the PFT level have a strong potential for reducing uncertainty in the simulation of regional climate models with finer spatial resolutions.展开更多
We show how the traditional grid based method for finding neutrino oscillation parameters △m2 and tan2θ can be combined with an optimization technique, Differential Evolution (DE), to get a significant decrease in...We show how the traditional grid based method for finding neutrino oscillation parameters △m2 and tan2θ can be combined with an optimization technique, Differential Evolution (DE), to get a significant decrease in computer processing time required to obtain minimal chi-square (χ2) in four different regions of the parameter space. We demonstrate efficiency for the two-neutrinos case. For this, the χ2 function for neutrino oscillations is evaluated for grids with different density of points in standard allowed regions of the parameter space of △m2 and tan2θ using experimental and theoretical total event rates of ehlorine (Homestake), Gallex+GNO, SAGE, Superkamiokande, and SNO detectors. We find that using DE in combination with the grid based method with smail density of points can produce the results comparable with the one obtained using high density grid, in much lesser computation time.展开更多
At present, most airlines adopted generally the same amount of compensa- tion strategy when needing to provide financial compensation to all flight delay passengers. However, due to the existence of differences in tra...At present, most airlines adopted generally the same amount of compensa- tion strategy when needing to provide financial compensation to all flight delay passengers. However, due to the existence of differences in travel time value, ticket fare, as well as the expectation of compensation for flight delays, the gap between the effect of same amount of compensation and many passengers' (especially the high-value ones) expectations is large, it results in that airlines need to pay higher cost of compensation, but the total effect of compensation for passengers are not better. This paper advanced four financial com- pensation strategies for flight delays, summarized their own characteristics, and took into account the interests of both airlines and passengers, built the optimization models of the four financial compensation strategies under the restriction of the airline's compensation cost and on the goal of the maximum total effectiveness of the financial compensation to all passengers. Finally, based on the specific circumstances of the flight delays, the paper discussed the method for airline to choose the optimal financial compensation strategy through solving four models and comparing the compensation effectiveness.展开更多
基金Under the auspices of the National Natural Science Foundation of China (No. 70373029)
文摘The policy of land transfer has greatly influenced the macro economy of China with the commencement of another innovation of land use system. Therefore, it is urgent to put forward some rational and feasible suggestions for local government to manage the market of land transfer. Moreover, it is important in the field of study on agricultural land use change to analyze the spatial differentiation and structural specification of land transfer, which are caused by rural households' behavior. This paper selected I l factors covering four aspects of rural households' family structure, family location, family income structure and the natural quality of land resources, all of which influence the behavior differentiation of rural households, to establish the index model indicating spatial differentiation of land transfer. Results show that the spatial differentiation of land transfer can be divided into four degrees and three categories through analyzing rural households' questionnaires from Shanghai, Nanjing and Taizhou in the Changjiang (Yangtze) River Delta. Since up to 80% of rural households belong to middle degrees, it can be concluded that the rural land market develops evenly in the study areas. And it is also indicated that the natural quality of land resources and the maximum income of rural land are most important factors influencing the spatial differentiation of land transaction. Considering different factors, the countermeasures can be carried out to enhance the spatial differentiation of land transfer so as to promote economic development and social security of rural China. All in all, both micro- factors and macro-factors influencing rural households' behavior of rural land transfer should be taken into account in order to make spatial differentiation and structural specification of rural land transfer notable.
文摘The objectives of this study are to assess land s ui tability and to predict the spatial and temporal changes in land use types (LUTs ) by using GIS-based land use management decision support system. A GIS databas e with data on climate, topography, soil characteristic, irrigation condition, f ertilizer application, and special socioeconomic activities has been developed a nd used for the evaluation of land productivity for different crops by integrati ng with a crop growth model-the erosion productivity impact calculator (EPIC). International food policy simulation model (IFPSIM) is also embedded into GIS fo r the predictions of how crop demands and crop market prices will change under a lternative policy scenarios. An inference engine (IE) including land use choice model is developed to illustrate land use choice behavior based on logit models , which allows to analyze how diversified factors ranging from climate changes, crop price changes to land management changes can affect the distribution of agr icultural land use. A test for integrated simulation is taken in each 0.1° by 0.1° grid cell to predict the change of agricultural land use types at globa l level. Global land use changes are simulated from 1992 to 2050.
基金Under the auspices of National Basic Research Program of China(No.2011CB952001)National Natural Science Foundation of China(No.41340016,412013860)
文摘As an important part of land use/cover change(LUCC), historical LUCC in long time series attracts much more attention from scholars. Currently, based on the view of combining the overall control of cropland area and ′top-down′ decision-making behaviors, here are two global historical land-use datasets, generally referred as the Sustainability and the Global Environment datasets(SAGE datasets) and History Database of the Global Environment datasets(HYDE datasets). However, at the regional level, these global datasets have coarse resolutions and inevitable errors. Considering various factors that influenced cropland distribution, including cropland connectivity and the limitation of natural and human factors, this study developed a reconstruction model of historical cropland based on constrained Cellular Automaton(CA) of ′bottom-up′. Then, an available labor force index is used as a proxy for the amount of cropland to inspect and calibrate these spatial patterns. Applied the reconstruction model to Shandong Province, we reconstructed its spatial distribution of cropland during 8 periods. The reconstructed results show that: 1) it is properly suitable for constrained CA to simulate and reconstruct the spatial distribution of cropland in traditional cultivated region of China; 2) compared with ′SAGE datasets′ and ′HYDE datasets′, this study have formed higher-resolution Boolean spatial distribution datasets of historical cropland with a more definitive concept of spatial pattern in terms of fractional format.
基金Under the auspices of Mexican National Council for Science and Technology (No 2008-01-87972)
文摘Forest fire is one of the major causes of forest loss and therefore one of the main constraints for sustainable forest management worldwide.Identifying the driving factors and understanding the contribution of each factor are essential for the management of forest fire occurrence.The objective of this study is to identify variables that are spatially related to the occurrence and incidence of the forest fire in the State of Durango,Mexico.For this purpose,data from forest fire records for a five-year period were analyzed.The spatial correlations between forest fire occurrence and intensity of land use,susceptibility of vegetation,temperature,precipitation and slope were tested by Geographically Weighted Regression(GWR) method,under an Ordinary Least Square estimator.Results show that the spatial pattern of the forest fire in the study area is closely correlated with the intensity of land use,and land use change is one of the main explanatory variables.In addition,vegetation type and precipitation are also the main driving factors.The fitting model indicates obvious link between the variables.Forest fire was found to be the consequence of a particular combination of the environmental factors,and when these factors coexist with human activities,there is high probability of forest fire occurrence.Mandatory regulation of human activities is a key strategy for forest fire prevention.
文摘In this paper, another form of KKM type theorem on generalized convex spaces is obtained and the problems of von Neumann-Fan type sup inf sup inequalities and variational inequalities are discussed for their applications.The main results improve and generalize the corresponding results in previous papers.
文摘In this paper we report on recent development in the areas of optical vortices generated by micro-optical elements and applications of optical vortices, including optical manipulation, radial polarization and secure free space optical communication
文摘Nowadays, about 80% of the Danube floodplain--Romanian sector are embanked and arranged with desiccation works and locally with drainage. Once with increasing pressures on the system and the complexity of the issues, there has been developed a number of mechanisms by which human activity (LU change) influence the stability and services of ecosystems and the need for planning tools are changing rapidly. Motivated by dramatic climatic change in recent decades and especially increased frequency of extreme events--2006 and 2010, the study focused on developing models and scenarios of climatic change, especially those related to land use change and flooding affecting local communities/regions. Thus, in the given circumstances, the best option is to foreseen a policy on the Lower Danube riverbed, followed by a series of advanced tools for exploring the 4D reconnection (longitudinal, lateral, vertical and temporal) and a well prepared monitoring system which alert address to detected threats. 4D reconnection of the lower Danube floodplain will provide a spatial planning tool, developed in accordance with this three features, and built to design, analyse and evaluate long-term policies in an ecological, social, economic and cultural context.
文摘In Tokyo, as residential areas exist in the urban areas and are composed of areas owned by individual land owners, basically spatial changes are brought by redevelopments of each sites conducted by individual circumstances and motivations. Continuous redevelopments and spatial changes can be found dispersedly in areas. Once the spatial change in a certain site occurred in an area as a building, it will be contained in the built environment of the residential area which is defined by residents, planners and designers who will take part in the following spatial changes. In Tokyo, public transportation facilities are well developed, and residents' daily life involves activities such as a slow walking and bicycle, etc. around the place of residence near the public transportation hubs, each living territories are formed in this kind of manner. Considering the maintenance of spatial value in residential areas while understanding transformation of visual local environment in residential areas which focuses on appearance of each spatial change in an area of street will be of significant importance. In this paper, the authors try to describe interactions of spatial changes in existing urban residential areas focusing on utility of players who might take part in the following spatial changes and the method of discrete choice model.
文摘This study aims to analyze spatial landuse and farming system of reclamated tidal lowland in South Sumatra, Indonesia by using remote sensing technology and GIS in knowing the distribution of landuse change of tidal lowland. From these conditions, it can see cropping patterns on each of the secondary block and its relation to the condition of the water system network. The study was carried out in Delta Saleh areas. The used methodology was field survey and remote sensing technique. It was combined with GIS technology for spatial analysis. Over the last 11 years (1992-2002), a decline in the paddy field area is from 23,619.4 ha to 18,518.40 ha (27.65%). A decrease of river acreage (water body) occurred from 6,643.53 ha to 6,559.83 ha. In 1992 it has not detected any coconut plantation, while in 2001 it showed an area of coconut plantation 3,422.84 ha and 3,822.84 ha in 20l l. Significant changes are also presented in primary mangrove forest, widespread declining around 1,940.88 ha (147.20%). Most of the mangrove forest was converted into secondary mangrove forest and scrub. Linkage with topography type showed that the land with topography Type A was majority for paddy fields 250.28-262.80 ha (62.72%-65.59%). Mixed crop fields were in second place with acreage of 90.66-107.36 ha (22.72%-26.80%). The land with topography Type B showed the widest paddy fields (283.14-314.20 ha or 70.70%-78.48%), followed by upland crops. The land with topography Type C showed that paddy fields were 283.03-300.41 ha (70.66%-75.02 %), followed by upland crops 94.85-102.78 ha (23.69%-25.66%), and coconut was the smallest 0.09-0.27 ha. Generally, the cropping index was 100 on PS-I (planting season 1) for BL-I (business land 1) and BL-2 planted with paddy fields, while the PS-2 are generally not cultivated land (fallow).
文摘Knowledge and management of soil pH, particularly soil acidity across spatially variable soils is important, although this is greatly ignored by farmers. The objective of the study was to evaluate in-field spatial variability of soil pH, and compare the efficiency of managing soil pH through site-specific method vs. uniform lime application. The study was conducted on three sites with study sites I and II (23°50' S; 29°40' E), and study sites IIl (23°59' S; 28°52' E) adjacent to each other in the semi-arid regions of the Limpopo Province, South Africa. Soil samples were taken in four replicates from geo-referenced locations on a regular grid of 30 m. Soils were analyzed for pH, and SMP buffer pH. Soil maps were produced with Geographic Information System (GIS) software, and soil pH datasets were interpolated using a geostatistical tool of inverse distance weighing (IDW). Soil pH in the fields varied from 3.93 to 7.00. An excess amount of lime as high as 30 t/ha under uniform lime application were recorded. These recommendations were in excess on field areas that needed little or no lime applications. Again, there was an under applications of lime as much as 35 t/ha for uniform liming applications. This under- and over-recommendations of lime based on average soil pH values suggests that uniform soil acidity correction and soil pH management strategy is not an appropriate strategy to be adopted in these fields with spatially variable soils. The field can be divided into lime application zones of (1) high rates of lime, (2) low rates of lime and (3) areas that requires no lime at all so that lime rates are applied per zone. A key to site-specific soil acidity correction with lime is to reach ideal soil pH for the crop in all parts of the field.
文摘The term geopoetics has a wide interpretation. It is defined as a project of the cultural activity aimed at creating and changing territorial myths and research path, which considers the interaction between literary creativity and geographical space. Defining this term, it is possible to introduce a geopoetical analysis diagram based on three interconnected positions: the writer's personality, the universe of an artwork and its characters. The Last Novik--A historical novel by Lazhechnikov analysis example presented on a diagram reveals the relationship between time and space in the literary work, as well as the author's interaction with the described events.
基金Supported by the National Natural Science Foundation of China(No.11274092,11274091,11304026)the Fundamental Research Funds for the Central Universities(No.14B10128)
文摘Intensity of cavitation is significant in ultrasonic wastewater treatment,but is complicated to measure.A time difference based method of ultrasonic cavitation measurement is proposed.The time differences at different powers of 495 kHz ultrasonic are measured in experiment in comparison with conductimetric method.Simulation results show that time difference and electrical conductivity are both approximately positive proportional to the ultrasonic power.The degradation of PNP solution verifies the availability in wastewater treatment by using ultrasonic.
文摘The doors and windows are the throat of the building. This paper discusses the fundamental role of the doors and windows of the building, and the dominant roles such as spatial organization and control of light, and to study the recessive function of windows and doors from aspects of the psychological impact, cultural significance and decoration. After exploring the characteristics of modem windows and doors, it studies the design elements of modem windows and doors and summed up the features that the initiative to make use of the environment. Basic from three levels as the basic form of design; windows and buildings, and the social and natural environment of the unified design; doors and windows to take the initiative to study the nature.
基金National Natural Science Foundation of China (Grant Nos. 10901018 and 11001002)the Shanghai Leading Academic Discipline Project (Grant No. J50101)the Fundamental Research Funds for the Central Universities
文摘Let X be an RD-space. In this paper, the authors establish the boundedness of the commutator Tbf = bTf-T(bf) on Lp , p∈(1,∞), where T is a Calderón-Zygmund operator related to the admissible function ρ and b∈BMOθ(X)BMO(X). Moreover, they prove that Tb is bounded from the Hardy space H1ρ(X) into the weak Lebesgue space L1weak(X). This can be used to deal with the Schrdinger operators and Schrdinger type operators on the Euclidean space Rn and the sub-Laplace Schrdinger operators on the stratified Lie group G.
基金supported by the State Administration of Foreign Experts Affairs of China,National Natural Science Foundation of China (Grant Nos. 10971136,10831003,61072147,11071159)Chunhui Plan of the Ministry of Education of China,Zhejiang Innovation Project (Grant No. T200905)the Natural Science Foundation of Shanghai and the Shanghai Leading Academic Discipline Project (Grant No.J50101)
文摘The invariant subspace method is refined to present more unity and more diversity of exact solutions to evolution equations. The key idea is to take subspaces of solutions to linear ordinary differential equations as invariant subspaces that evolution equations admit. A two-component nonlinear system of dissipative equations is analyzed to shed light oi1 the resulting theory, and two concrete examples are given to find invariant subspaces associated with 2nd-order and 3rd-order linear ordinary differentii equations and their corresponding exact solutions with generalized separated variables.
基金the National Key Research&Development Program of China(2019YFA0607203,2017YFA0604404)the National Natural Science Foundation of China(41901327,41671398,41871318)+2 种基金the Guangdong Basic and Applied Basic Research Foundation(2019A1515010823)the Fundamental Research Funds for the Central Universities(19lgpy41)Natural Resources of the People’s Republic of China(GS(2020)2879)。
文摘Land use projections are crucial for climate models to forecast the impacts of land use changes on the Earth’s system.However,the spatial resolution of existing global land use projections(e.g.,0.25°×0.25°in the Land-Use Harmonization(LUH2)datasets)is still too coarse to drive regional climate models and assess mitigation effectiveness at regional and local scales.To generate a high-resolution land use product with the newest integrated scenarios of the shared socioeconomic pathways and the representative concentration pathways(SSPs-RCPs)for various regional climate studies in China,here we first conduct land use simulations with a newly developed Future Land Uses Simulation(FLUS)model based on the trajectories of land use demands extracted from the LUH2 datasets.On this basis,a new set of land use projections under the plant functional type(PFT)classification,with a temporal resolution of 5 years and a spatial resolution of 5 km,in eight SSP-RCP scenarios from 2015 to 2100 in China is produced.The results show that differences in land use dynamics under different SSP-RCP scenarios are jointly affected by global assumptions and national policies.Furthermore,with improved spatial resolution,the data produced in this study can sufficiently describe the details of land use distribution and better capture the spatial heterogeneity of different land use types at the regional scale.We highlight that these new land use projections at the PFT level have a strong potential for reducing uncertainty in the simulation of regional climate models with finer spatial resolutions.
基金the Higher Education Commission(HEC) of Pakistan for its financial support through Grant No.17-5-2(Ps2-044) HEC/Sch/2004
文摘We show how the traditional grid based method for finding neutrino oscillation parameters △m2 and tan2θ can be combined with an optimization technique, Differential Evolution (DE), to get a significant decrease in computer processing time required to obtain minimal chi-square (χ2) in four different regions of the parameter space. We demonstrate efficiency for the two-neutrinos case. For this, the χ2 function for neutrino oscillations is evaluated for grids with different density of points in standard allowed regions of the parameter space of △m2 and tan2θ using experimental and theoretical total event rates of ehlorine (Homestake), Gallex+GNO, SAGE, Superkamiokande, and SNO detectors. We find that using DE in combination with the grid based method with smail density of points can produce the results comparable with the one obtained using high density grid, in much lesser computation time.
文摘At present, most airlines adopted generally the same amount of compensa- tion strategy when needing to provide financial compensation to all flight delay passengers. However, due to the existence of differences in travel time value, ticket fare, as well as the expectation of compensation for flight delays, the gap between the effect of same amount of compensation and many passengers' (especially the high-value ones) expectations is large, it results in that airlines need to pay higher cost of compensation, but the total effect of compensation for passengers are not better. This paper advanced four financial com- pensation strategies for flight delays, summarized their own characteristics, and took into account the interests of both airlines and passengers, built the optimization models of the four financial compensation strategies under the restriction of the airline's compensation cost and on the goal of the maximum total effectiveness of the financial compensation to all passengers. Finally, based on the specific circumstances of the flight delays, the paper discussed the method for airline to choose the optimal financial compensation strategy through solving four models and comparing the compensation effectiveness.