西部地区经济社会发展研究——基于因子和聚类分析的西部12省综合评价

西部地区经济社会发展是我国经济社会发展的重要组成部分,研究西部地区的经济社会发展对实现整个国家经济社会协调发展具有重要的战略意义.根据《中华人民共和国国民经济和社会发展第十一个五年规划纲要》中《"十一五"时期经济社会发展的主要指标》为蓝本,选取24个指标构建了西部地区经济社会发展综合评价指标体系,基于因子分析法利用SPSS13.0进行数据处理,根据西部地区各省、市和自治区的公共因子得分和综合得分,运用聚类分析法将西部地区划分为2个经济社会发展类型区和5个亚区,并逐类进行综合评价.最后根据西部地区经济社会发展类型区,提出了西部地区经济社会协调发展的若干对策.     

伸缩仪台站维护管理要点分析

总结了宜昌地震台SS-Y伸缩仪在安装、调试、维护、管理等方面的经验.     

一种高效的迭代OFDM频偏估计算法

提出了一种改进的正交频分复用（Orthogonal Frequency Division Multiplexing,OFDM）载波频率偏移估计算法并通过MATLAB进行仿真.仿真结果表明算法对小数载波频率偏移估计精度高并且其算法复杂度低.     

Vertical amplitude reduction of Rayleigh waves by a row of piles in a poroelastic half‐space

A row of rigid piles is addressed as the countermeasures for isolating Rayleigh waves in a poroelastic half‐space. The complex characteristic equations for Rayleigh waves are derived via Biot's theory and their existence conditions are given. The piles are modeled as Euler–Bernoulli beams with longitudinal displacements and the diffracted field by each pile is constructed only with Rayleigh waves. Six infinite linear systems of algebraic equations are obtained in terms of the equilibrium of forces and continuity of displacements at the pile–soil interfaces. The systems are subsequently solved in the complex least‐squares sense. The influence of certain pile and soil characteristics such as the permeability of poroelastic soil, spacing between the piles and length of the piles on the isolating performance of a pile barrier is investigated. Computed results show that the permeability of poroelastic soil displays a significant effect on the vertical amplitude reduction of Rayleigh waves. Copyright © 2009 John Wiley & Sons, Ltd.     

Study on Effects of Building Morphology on Urban Boundary Layer Using an Urban Canopy Model

An urban canopy model is incorporated into the Nanjing University Regional Boundary Layer Model. Temperature simulated by the urban canopy model is in better agreement with the observation, especially in the night time, than that simulated by the traditional slab model. The coupled model is used to study the effects of building morphology on urban boundary layer and meteorological environment by changing urban area, building height, and building density. It is found that when the urban area is expanded, the urban boundary layer heat flux, thermal turbu- lence, and the turbulent momentum flux and kinetic energy all increase or enhance, causing the surface air temperature to rise up. The stability of urban atmospheric stratiˉcation is a?ected to diffierent extent at diffierent times of the day. When the building height goes up, the aerodynamic roughness height, zero plane displacement height of urban area, and ratio of building height to street width all increase. Therefore, the increase in building height results in the decrease of the surface heat flux, urban surface temperature, mean wind speed, and turbulent kinetic energy in daytime. While at night, as more heat storage is released by higher buildings,thermal turbulence is more active and surface heat flux increases, leading to a higher urban temperature. As the building density increases, the aerodynamic roughness height of urban area decreases, and the effect of urban canopy on radiation strengthens. The increase of building density results in the decrease in urban surface heat flux, momentum flux, and air temperature, the increase in mean wind speed, and the weakening of turbulence in the daytime. While at night, the urban temperature increases due to the release of more heat storage.     

土地管理信息系统建立过程中地图数据质量问题讨论

地图数据对于土地管理信息系统来说至关重要,地图数据质量的好坏直接影响到信息系统的质量和应用效果乃至信息系统建设的成败。该文对土地管理信息系统建立过程中有关地图数据质量问题进行分析探讨并提出了提高地图数据质量的方法。     

Orientation of Galaxies in the Local Supercluster: A Review

The progress of the studies on the orientation of galaxies in the Local Supercluster (LSC) is reviewed and a summary of recent results is given. Following a brief introduction of the LSC, we describe the results of early studies based on two-dimensional analysis, which were mostly not conclusive. We describe next the three-dimensional analysis, which is used widely today. Difficulties and systematic effects are explained and the importance of selection effects is described. Then, results based on the new method and modern databases are given, which are summarized as follows. When the LSC is seen as a whole, galaxy planes tend to align perpendicular to the LSC plane with lenticulars showing the most pronounced tendency. Projections onto the LSC plane of the spin vectors of Virgo cluster member galaxies, and to some extent, those of the total LSC galaxies, tend to point to the Virgo cluster center. This tendency is more pronounced for lenticulars than for spirals. It is suggested that ‘field’ galaxies, i.e., those which do not belong to groups with more than three members, may be better objects than other galaxies to probe the information at the early epoch of the LSC formation through the analysis of galaxy orientations. Field lenticulars show a pronounced anisotropic distribution of spin vectors in the sense that they lay their spin vectors parallel to the LSC plane while field spirals show an isotropic spin-vector distribution.     

Differentiation of Rural Households′ Consciousness in Land Use Activities: A Case from Bailin Village,Shapingba District of Chongqing Municipality,China

What rural households think and what kind of strategies they take, the basic driving force in land use activities, contribute greatly to the increase of their own revenues, the development of agricultural yields, and even the prosperity of rural areas. Differentiation in rural household behaviors and their consciousness in land use activities is widespread in rural China nowadays. It is important to understand the changing characteristics and laws of land use behaviors of rural households driven by their consciousness, so as to regulate their land use activities. In most empirical studies of land use change at rural household level, the land use consciousness, which acts directly on land use behaviors, is often neglected. In our research, the changes of land use behaviors of rural households are analyzed, through identifying how the land use consciousness affect the land use objectives, land management scales and land inputs of all the rural households in Bailin Village of Chongqing Municipality in the western mountainous China. Also, how the land use consciousness of different rural households comes into being under external stimuli is examined and the self-adjustment process of their consciousness according to their own conditions is also discussed. Finally, broad policy instruments are suggested to promote the rationalization of rural households′ land use consciousness and the standardization of their land use behaviors.     

Spatial Variation of Dissolved Organic Carbon in Soils of Riparian Wetlands and Responses to Hydro-geomorphologic Changes in Sanjiang Plain,China

Spatial variation of dissolved organic carbon(DOC) in soils of riparian wetlands and responses to hydro-geomorphologic changes in the Sanjiang Plain were analyzed through in situ collecting soil samples in the Naoli River and the Bielahong River. The results showed that the average contents of DOC for soil layer of 0–100 cm were 730.6 mg/kg, 250.9 mg/kg, 423.0 mg/kg and 333.1 mg/kg respectively from riverbed to river terrace along the transverse directions of the Naoli watershed. The content of the soil DOC was the highest in the riverbed, lower in the high floodplain and much lower in the river terrace, and it was the lowest in the low floodplain. The difference in the content and vertical distribution of DOC between the riverbed and the three riparian wetlands was significant, while it was not significant among the low floodplain, the high floodplain and the river terrace. The variability of soil DOC was related to the hydrological connectivity between different landscape position of the riparian wetlands and the adjacent stream. Extremely significant correlations were observed between DOC and total organic carbon(TOC), total iron(TFe), ferrous iron(Fe(II)) whose correlation coefficients were 0.819, –0.544 and –0.709 in riparian wetlands of the Naoli River. With the increase of wetland destruction, soil p H increased and soil DOC content changed. The correlation coefficients between soil DOC and TOC, TFe, Fe(II) also changed into 0.759, –0.686 and –0.575 respectively in the Bielahong River. Under the impact of drainage ditches, the correlations between soil DOC and TFe, Fe(II) were not obvious, while the soil p H was weakly alkaline and was negatively correlated with soil DOC in the previous high floodplain. It indicates that riparian hydro-geomorphology is the main factor that could well explain this spatial variability of soil DOC, and the agricultural environmental hydraulic works like ditching also must be considered.     

Growth and energy budget of juvenile lenok Brachymystax lenok in relation to ration level

We evaluated the effect of ration level(RL) on the growth and energy budget of lenok Brachymystax lenok. Juvenile lenok(initial mean body weight 3.06±0.13 g) were fed for 21 d at five different ration levels: starvation,2%,3%,4% bwd(body weight per day,based on initial mean values),and apparent satiation. Feed consumption,apparent digestibility,and growth were directly measured. Specific growth rates in terms of wet weight,dry weight,protein,and energy increased logarithmically with an increase in ration levels. The relationship between specific growth rate in terms of wet weight(SGRw,%/d) and RL(%) was characterized by a decelerating curve: SGRw=-1.417+3.166ln(RL+1). The apparent digestibility coefficients of energy exhibited a decreasing pattern with increasing ration level,and there was a significant difference among different RLs. Body composition was significantly affected by ration size. The relationship between feed efficiency rate in terms of energy(FERe) and RL was: FERe=-14.167+23.793RL–3.367(RL)2,and the maximum FERe was observed at a 3.53% ration. The maintenance requirement for energy of juvenile lenok was 105.39 k J BW(kg)-0.80/d,the utilization efficiency of DE for growth was 0.496. The energy budget equation at satiation was: 100IE=29.03FE+5.78(ZE+UE)+39.56 HE+25.63 RE,where IE is feed energy,FE is fecal energy,ZE+UE is excretory energy,HE is heat production,and RE is recovered energy. Our results suggest that the most suitable feeding rate for juvenile lenok aquaculture for wet weight growth is 2.89% bwd,whereas for energy growth,the suggested rate is 3.53% bwd at this growth stage.