Urbanization causes land cover changes which lead to deeper regional social, economic, and environmental changes and have important influences on environment and climate on the global scale. The coarse or moderate resolution remote sensing images may have much mixed pixels which limit their applications in the study of urban remote sensing. High spatial resolution remote sensing images with the advantages of high spatial resolution,high definition, and rich information, greatly improve the application of remote sensing in the research area of land use and land change. Accurate urban land use classification is the basis of the study of urban LUCC, and the high spatial resolution remote sensing images become one of the most important data sources because of their inherent advantages. We report the development and features of high resolution remote sensing images, the methods of remote sensing images classification, and their applications in extracting urban information. Much attention is paid to the representative classification methods in urban land use and to the ways of extracting information of buildings, roads, and vegetation in urban environment. The paper indicates that, compared to the traditional classification methods based on the level of pixels, the object-oriented image classification method which makes full use of high spatial resolution remote sensing images is the most widely used method. The discussion focuses on the current status and perspectives of the object-oriented method. With the help of high spatial resolution remote sensing images, accurate urban thematic information can be extracted effectively and it plays a significant role in the study of urban LUCC.
In this paper we study the K-theory of the integral group ring Ζ[C4×C4]. We prove that the relative SK1 group of the integral group ring Ζ[C4×C4] is an elementary Abelian group of rank-3. We also show that the 4-rank of K2(Ζ[C4×C4]) is at least 1 and the 2-rank of K2(Ζ[C4×C4]) is at least 10.
In this work, the basis of augmentation ideal I of Burnside ring of a finite cyclic group under the action by any maximal subgroup is studied. The recursion formula of the nth power In of the augmentation ideal I is given. Furthermore, the consecutive quotient In/I(n+1) of the nth power In by the (n+1)th power of the ideal I is discussed, and its structure is determined in general.
Two kinds of full implicit numerical schemes for stochastic differential equations in the Itô sense are given via construction of the numerical methods for the equivalent stochastic differential equations in the sense of Stratonovich and Backward-Itô. This approach could be applied to the stochastic differential equations with one noise, and we prove that the two methods which are generated by the equivalent stochastic differential equations are of mean-square order 1.
Complex curve approximation is a basic problem in CAGD, and the traditional de Casteljau algorithm is commonly used with the fixed parameter value of 0.5. To achieve better subdivided curves in approximation, we consider two different choices of the subdivision parameters for the planar Bézier curves. The two choices of the parameter are associated with convex hull area minimization and convex hull flat minimization. The definitions and algorithms of the parameters are proposed in both cases. By analyzing the parameters for different types of curves, we find that the optimal parameter volues are close to 0.5 when the curve segments are short enough. This fact indicates that it is reasonable to select the parameter value of 0.5 for the small curve segments. For some complex curves the least flat method improves the efficiency of the subdivision by more than 50%, compared to the traditional de Casteljau method. For other curves, the two methods have similar efficiency.
We propose a homogeneous infeasible-interior-point algorithm for semidefinite programming(SDP) in a new wide neighborhood in order to achieve low iteration complexity and get better experiement numerical results. Complementarity problem (MCP) is the KKT condition of SDP. We sovle MCP by constructing a homogeneous MCP model (HMCP) and proposing a new wide neighborhood. Then we derive the optimal solution of SDP. This algorithm can be easily used to determine whether SDP is feasible or not. At the direction of NT, we prove that the iteration poin is convergent in new wide neighborhood and the iteration complexity is O(√nlogL), where n is the dimension of SDP and L=Tr(X0S0)/ε with ε being the required precision and (X0,S0) the initial point. This algorithm has lower complexity degree than other algorithms for SDP. The numerical experiment is provided. We have proved that this algorithm is better than other infeasible-interior-point algorithms in numerical experimentel results.
A new numerical solution is provided for Volterra integral equation of the second kind. The integral equation is discretized by numerical difference method and is then formulated as nonlinear algebraic equations, which is solved by iteration approach. Thus the numerical solution for this kind of Volterra Integral equation is provided. The accuracy of the proposed approach is analyzed and is proved to reach the order of Δt2, which meets the need of engineering computation. A case study is provided to verify the feasibility of the method. The difference between the numerical solution and the analytical solution is about 10-5. If numerical differential method with higher order is applied to discretize the integral equation, results of higher order accuracy will be obtained.
In this work we propose a practical entanglement classification scheme for pure states of 2×L×M×N×H under the stochastic local operation and classical communication (SLOCC), which generalizes the method explored in the entanglement classification of 2×L×M×N to the five-partite system. The entangled states of 2×L×M×N×H system are first classified into different coarse-grained standard forms by using matrix decompositions, and then fine-grained identifications of two inequivalent entangled states with the same standard form are made by using the matrix realignment technique. As a practical example, the entanglement classes of the five-qubit system of 2×2×2×2×2 are presented.
We study the Josephson effect in s-wave superconductor/ferromagnet/p-wave superconductor junctions using the Matsubara Green function method. Three p-wave pairing states with different orbital parts are considered. We focus on the lowest unusual harmonic contribution (∝cosφ) to Josephson current, where φ is a phase difference across the junction. We evaluate the dependence of this unusual term on the strength of magnetization and the width of the central ferromagnet layer. It is confirmed that the 0-π transition also occurs in s-wave superconductor/ferromagnet/p-wave junctions. A possible spintronic application of the present Josephson junction has been discussed.
In the studies of optical transmission characteristics of electromagnetic wave, TE/TM modes are often used to describe the polarization mode of electromagnetic wave. However, the definitions of TE/TM polarization are different in different transmission systems and are often mixed with s/p states, inducing some confusing concepts and contradictory results. Based on electromagnetic theory,we deeply derive and analyze the possible polarization modes in different transmission systems, explain the existent reasons and possible states of TE/TM polarization modes, compare the possible states with s/p states to illustrate the differences, and resolve the confusing polarization problems one by one. This work will sweep away the obstacles for future researches of electromagnetic fields.
Asymmetry is often designated as right- and left-handed. The right- and left-handed helical hypergravity (HG) field can be artificially produced. In this paper, it is shown that the α-amylase activity is dependent on both the magnitude and direction of HG within the range between 1 g and 9 000 g. The right-handed HG has larger enhanced effect on enzyme activity than the left-handed HG. Considering the circadian rhythm of natural gravity on the earth, it is suggested that circadian rhythm of natural gravity may be an important mechanical factor for the origin of biological circadian rhythms.
A sensitive and specific competitive enzyme-linked immunosorbent assay (cELISA) for qualitative and quantitative analysis of α-lactalbumin (α-LA) is described. New Zealand white rabbits were immunised to obtain α-LA PcAb. By using sodium periodate oxidative method,the α-LA labeled by horseradish peroxidase (HRP) was prepared. Then cELISA was developed for α-LA quantitative analyses. The prepared PcAb has high specificity without obvious cross-reactivity and its titer is 1:80 920. The labeling rate of the enzyme-labeled antigen is 66.67%. The correlation coefficient of the established cELISA was 0.998 57, and the recoveries were estimated to be in the range from 86.00% to 117.50%. The variation coefficient is less than 5%. Compared with the national standard electrophoresis method,the established cELISA was useful analytical tool for rapid qualitative and quantitative analysis of α-LA in food samples.
Using the AIC-1000 air negative ion concentration tester, we made field observations of the aero anion resources in Longsheng county and simulated the spatial distribution by the inverse distance weighting interpolation method. The results show that the average of aero anion concentrations at all the monitoring sites in the county is 4 265 per cubic centimeter,and the county is suitable to develop aero anion healthy tourism.The aero anion resources distribute in the county as follows.The concentration of the aero anion in the north is generally higher than in the south.The concentration in sparsely populated area is much higher than in the densely populated areas.The concentration in forest area is much higher than in other vegetation covering area; and the concentration in the region with waterfalls, streams,and other dynamic water is generally high. Based on the above results, we suggest that the local government exploit the aero anion resources in Longsheng county as follows:1) protecting the forests and the water resources and propagating the health benefits of aero anion,2) dividing the functional areas rationally based on the spatial distribution of aero anion in order to fully exploit the aero anion resources,3) allocating the green space rationally and constructing water landscape in the area with low concentration,and 4) establishing an announcing system of aero anion concentration to realize the dynamic monitoring of the aero anion.
Settlement archaeology with settlement sites as research object is an essential method of archaeology. We selected the western part of Liaoning as the research area where there are numerous settlement sites. Decision tree classification and improved clustering analysis method that is based on the weights of the site level were used to divide settlement sites and to study the internal structures and control ranges. The analysis results show that the settlement distribution was affected by the drainage, landscape,and climate and it had different forms in different periods. The biggest settlement in the area was located in the tributary basin of Daling river, which is very close to the first county of Liaoxi, Yangle, in the historical record.Based on statistical analysis of historic site grade, the ratio of high-level sites in all the settlements decreased gradually to about 5%, and the control range of high-level settlements of different sites is in close relation with the location and the amount of settlements.
By applying weighted TOPSIS method, we evaluate the comprehensive strength of Chinese commodity exchange markets from the scale, structure, and speed aspects. The results show that the comprehensive strength of market in eastern region is much stronger than in middle and western regions. Consequently, we study the time-spatial evolution analysis using kernel density estimation and ESDA. The results are given as follows. 1) Though the growth momentum has been strong, some discrepancies occur at separate stages and present polarization phenomenon. 2) The strength of market tends to increase in west-east direction and presents an inverted U-shape, and the space autocorrelation is obvious with some heterogeneity in some provincial units. 3) Path dependence, geographical conditions, technological impact, and the process of opening-up are the dominant mechanisms of spatial-temporal segregation of market strength.
This study is based on the third to sixth census data in Urumqi from 1982 to 2010. We use methods of cluster analysis and ESDA to analyze the national living pattern and its evolution. Some conclusions are drawn as follows. Hetian street, Dongmen street, and Changjiang road are the centers of the population density distribution in Urumqi. The extension has a fanlike pattern which extends along the beach expressway and expands to the north and south in Urumqi. The national living pattern shows a strong spatial autocorrelation. The gathering degrees of Han and Uygur are obviously higher than those of other ethnic groups. The living patterns of all nationalities changed dramatically from simple and typical homogeneity to complicated and typical heterogeneity during the period from 1982 to 2010. The fusion among various nationalities has greatly improved.
Biomass pyrolysis technology is important for biomass utilization. In this paper, we auggest application of infrared heating in biomass pyrolysis reaction. According to the infrared spectra of biomass and its macromolecular intermediate product in the pyrolysis process we determine the infrared absorption bands in the pyrolysis process and select infrared coating. We have designed furnace body structure of biomass pyrolysis reactor based on infrared heating and performed combustion numerical simulation of the combustion chamber of furnace body, using ANSYS fluent software, to determine the optimal temperature field distribution.
Karst thermal spring group in Shiqian county has a high commercial value due to the rich minerals and trace elements. The water chemistry data in different periods are collected and analyzed to study hydrogochemical characteristics of the thermal spring group in Shiqian county. The results indicate that Ca2+and Mg2+ are the major cations and the major anions are SO2-4 and HCO-3. The thermal springs are alkaline water and recharged by precipitation. The hydrochemical types are SO4 ·HCO3-Ca ·Mg, HCO3 ·SO4-Ca ·Mg, and HCO3-Ca ·Mg. Water chemistry types of thermal spring group are controlled by the water-rock interaction in the process of precipitation infiltration into deep water cycle. The thermal spring of the HCO3-Ca · Mg type is predominated by carbonate minerals dissolution, and the HCO3 · SO4 -Ca · Mg or the SO4 · HCO3-Ca · Mg types are controlled by the dissolution of sulfate evaporates in karst aquifer.
In addition to the direct disasters during the volcano eruption, some lava tubes often form in the course of the flow of basic magma. The existence of underground empty caves near the lava tubes reduces the stability of the earth's surface, and then secondary disasters may happen. The lava tubes found on the Moon and Mars not only can be used for further research, but also have been proved to be the best places to build detection base in future. Using the finite element method and based on the formation of the lava tubes, we establish the temperature evolution and the corresponding displacement and thermal stress field conditions. Furthermore, we determine the effects, on the stability of the lava tubes, of different physical parameters (the lava tube size, depth, and shape) by means of analyzing the evolution course of the principal stress.
Several shards of sacrificial red porcelain from Guan kiln of Jingdezhen during Xuande period were selected and study on the color mechanism was carried out using various non-destructive approaches. Microscopic observation shows that the different color areas have similar transparent glaze surfaces, and the color difference mainly depends on the red layer in glaze. Composition analysis results show that the contents of colorant copper for different color samples are almost the same. However, X-ray absorption fine structure (XANES) analysis reveals the differences in Cu chemical state among different hues of the samples. This indicates that the color mechanism of sacrificial red porcelain is closely related to the state of colorant copper.
This study focuses on the massive device characteristic of M2M communication. Considering the overload situation in H2H&M2M co-existence scenario of OFDMA cellular networks, we propose an admission control and resource allocation joint optimization algorithm. Considering the effect of control channel, we formulate a MINLP problem of maximizing the number of MTCDs admitted. Because of the complexity of MINLP problems, relaxed constraints are used to transform the MINLP problem into a convex problem, which is the upper-bound of the original problem. Furthermore, a low-complicity algorithm is proposed. Simulation results show that the algorithm has minor degradation compared with the upper-bound and is better than two other algorithms.