变倍系统中间量的控制与装校方法

本文主要讨论了ＪＳＺ８体视显微镜在研制过程中遇到的变倍系统装校问题及解决办法，简略描述其变倍系统的结构和技术要求，针对它与其它仪器的不同，在装校中如何做到既满足技术要求又力求快捷、简便。实质上变倍系统光轴共轴是问题的关键，通过对变倍系统各透镜组的光轴（即本文所指的中间量）进行调整和控制即可完成仪器的变倍系统部件的装校。

Variable Precision Rough Set and a Fuzzy Measure of Knowledge Based on Variable Precision Rough Set

Variable precision rough set (VPRS) is an extension of rough set theory (RST). By setting threshold value β , VPRS looses the strict definition of approximate boundary in RST. Confident threshold value for β is discussed and the method for deriving decision making rules from an information system is given by an example. An approach to fuzzy measures of knowledge is proposed by applying VPRS to fuzzy sets. Some properties of this measure are studied and a pair of lower and upper approximation operato...

Seize the long tail, traditional metamorphosis interconnection

the traditional enterprise transformation, thanks to the Internet is a hot topic in recent years, many companies are testing the waters, but the real success is not much. This article through to the kaiyuan long tail economy, crowdsourcing platform, C2B customization model and information system four aspects of the introduction and analysis, trying to traditional enterprise transformation of the Internet, to provide reference.

INTERFERENCE MITIGATING BASED ON FRACTIONAL FOURIER TRANSFORM IN TRANSFORM DOMAIN COMMUNICATION SYSTEM

The method of FRactional Fourier Transform (FRFT) is introduced to Transform Domain Communication System (TDCS) for signal transforming in the paper after theoretical analysis. The method yields optimal Basis Function (BF) by FRFT with optimal transform angle. The TDCS using the proposed method has wider usable spectrum, stronger robustness and better ability of anti non-stationary jamming than using usual methods, such as Fourier Transform (FT), Auto Regressive (AR), Wavelet Transform (WT), etc. The main simulation results are as follows. First, the Bit Error Rate (BER) Pb is close to theoretical bound of no jamming no matter in single tone or in linear chirp interference. Second, the interference-to-signal ratio J /E is at least 12dB more than that of Direct Spread Spectrum System (DSSS) under the same BER if the spectrum hopping-to-signal ratio is 1:20 in chirp plus hopping interfering. Third, the Eb /N 0(when estimation difference is 90% between trans- mitter and receiver) is about 3.5dB or about 0.5dB (when estimation difference is 10% between transmitter and receiver) more than that of theoretical result when no estimation difference un-der Pb=10-2.

Environmental Factors Affecting Temporal and Spatial Dynamics of Soil Erosion in Xingguo County, South China

By using soil erosion maps of four different time periods and a digital elevation model (DEM), in combination withthe remote sensing and GIS technologies, soil erosion dynamics in Xingguo County of Jiangxi Province in South Chinawere analyzed on both temporal and spatial scales in soils of different parent materials, altitudes and slopes. The resultsshowed that from 1958 to 2000 severe soil erosion was coming under control with a decreasing percentage of the land undersevere erosion. It was also found that the soils developed from Quaternary red clay, granite and purple shale were moresusceptible to soil erosion and that areas sitting between 200 to 500 m in altitude with a slope less than 3° or between7° to 20° where human activities were frequent remained to be zones where soil erosion was most likely to occur. Theseareas deserve special attention in monitoring and controlling.

AN ASSESSMENT OF LAND USE CHANGES IN FUQING COUNTYOF CHINA USING REMOTE SENSING TECHNOLOGY

Fuqing County of southeast China has witnessed significant land use changes during the last decade. Re mote sensing technology using multitemporal Landsat TM images was used to characterize land use types and to monitor land use changes in the county. Two TM scenes from 1991 and 1996 were used to cover the county and a five-year time period. Digital image processing was carried out for the remotely sensed data to produce classified images. The images were further processed using GIS software to generate GIS databases so that the data could be further spatially analyzed taking the advantages of the software. Land use change areas were determined by using the change detection technique. The comparison of the two classified TM images using the above technologies reveals that during the five study years, a large area of arable lands in the county has been lost and deforestation has taken place largely because of the dramatic in crease in built-up land and orchard. The conclusive statistical information is useful to understand the processes, causes and impacts of the land use changes in the county. The major driving force to the land use changes in the county ap peared to be the rapid economic development. The decision makers of the county have to pay more attention to the land use changes for the county’s sustainable development.

Event-based incremental updating of spatio-temporal database

Based on the relationship among the geographic events, spatial changes and the database operations, a new automatic (semi-automatic) incremental updating approach of spatio-temporal database (STDB) named as (event-based) incremental updating (E-BIU) is proposed in this paper. At first, the relationship among the events, spatial changes and the database operations is analyzed, then a total architecture of E-BIU implementation is designed, which includes an event queue, three managers and two sets of rules, each component is presented in detail. The process of the E-BIU of master STDB is described successively. An example of building’s incremental updating is given to illustrate this approach at the end. The result shows that E-BIU is an efficient automatic updating approach for master STDB.

Hybrid C a rrie r S prea d Based on 4-Weighted T ra nsform Spectrum System Fractional Fourier

Spread Spectrum （SS） is a promising technique to resist interference in wireless communication system In order to further improve this capability, this paper proposes a Hybrid Carrier （HC） SS system, combining 4-Weighted Fractional Fourier Transform （4-WFRFT） with SS technique. In this HC-SS system, due to the property of 4- WFRFT, the signal energy of proposed system is distributed on the time-frequency plane more evenly and symmmetrically, compared with the existing Single-Cartier （SC） and Multi-Carrier （MC） spread spectrum systems. In the selective channel, the proposed method can split the interference to a more broad range in order to reduce the influence, resulting in the better system perforrmnce. In addition, proposed system can be seen as the convergence of the existing SS techniques, which is a main feature in future.

Evolution of neurotransmitter gamma-aminobutyric acid, glutamate and their receptors

Gamma-aminobutyric acid （GABA） and glutamate are two important amino acid neurotransmitters widely present in the nervous systems of mammals, insects, round worm, and platyhelminths, while their receptors are quite diversified across different animal phyla. However, the evolutionary mechanisms between the two conserved neurotransmitters and their diversified receptors remain elusive, and antagonistic interactions between GABA and glutamate signal transduction systems, in particular, have began to attract significant attention. In this review, we summarize the extant results on the origin and evolution of GABA and glutamate, as well as their receptors, and analyze possible evolutionary processes and phylogenetic relationships of various GABAs and glutamate receptors. We further discuss the evolutionary history of Excitatory/Neutral Amino Acid Transporter （EAAT）, a transport protein, which plays an important role in the GABA-glutamate ＂yin and yang＂ balanced regulation. Finally, based on current advances, we propose several potential directions of future research.

Review of studies on land use and land cover change in Nepal

Land use and land cover(LULC) in Nepal has undergone constant change over the past few decades due to major changes caused by anthropogenic and natural factors and their impacts on the national and regional environment and climate.This comprehensive review of past and present studies of land use and land cover change(LUCC) in Nepal concentrates on cropland, grassland, forest, snow/glacier cover and urban areas. While most small area studies have gathered data from different sources and research over a short period, across large areas most historical studies have been based on aerial photographs such as the Land Resource Mapping Project in 1986. The recent trend in studies in Nepal is to focus on new concepts and techniques to analyze LULC status on the basis of satellite imagery, with the help of geographic information system and remote sensing tools. Studies based on historical documents, and historical and recent spatial data on LULC, have clearly shown an increase in cropland areas in Nepal,and present results indicating different rates and magnitudes. A decrease in forest and snow/glacier coverage is reported in most studies. Little information is available on grassland and urban areas from past research. The unprecedented rate of urbanization in Nepal has led to significant urban land changes over the past 30 years. Meanwhile, long term historical LUCC research in Nepal is required for extensive work on spatially explicit reconstructions on the basis of historical and primary data collection, including LULC archives and drivers for future change.

Advanced Communication System in Substation for Integrated Protection

This paper proposes an advanced substation integrated protection communication system based on the latest development in power system.The integrated protection communication system within a substation comprises a number of major components such as the merging unit, communication network and integrated protection unit.The design and capability evaluation of the communication network based on IEC61850 are focused on.Results show that huge information from 4 merging units can be transmitted real-time via adopting 100 Mbit/s optical fiber in a substation,and the proposed communication network is able to achieve required performance.

Soil pH Management across Spatially Variable Soils

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.

Paleoclimatic record from Chumbur-Kosa section in Sea of Azov region since Marine Isotope Stage 11

Abstract： Loess-paleosol sequences preserve records of climatic change during the Quaternary, which is important for paleoclimate study. In this study, a loess-palaeosol sequence from the Chumbur- Kosa （CK） site in the Sea of Azov region was investigated to reconstruct climatic variability during the Marine Isotope Stage （MIS）11- MIS 1, using proxies of grain size （GS）, magnetic susceptibility （xlf and Xfd（%））, carbonate content （CaCO3%） and soil color The results enabled formulation of a detailed description of the climatic characteristics related to each individual layer. The sequence indicates that the paleoclimate shifted progressively towards increasingly cooler, somewhat drier conditions. The CK section may thus be ideal for reconstructing climatie eondifions during the Middle and Late Pleistocene in the Sea of Azov region. However, the ）Of value of paleosol $2 in the CK profile indicates different characteristics from the other paleosol layers, dilution of carbonate resulting from carbonate leaching in L2 may be the main reason for the decrease in magnetic susceptibility. Furthermore, through simple analysis part of the environmental evolution process in the Sea of Azov region and Serbia during Middle and Late Pleistocene cycles. The climate cycle expressed by Xfd（%） and Xlf variations show similar patterns, with rapidly alternating cold and warm intervals. Nevertheless, although the two areas had different climatic regimes, geographical settings, and loess source areas, both exhibited similar climate change trends since the MIS 11.

Study on Simulating Spatial Distribution and Varying Patterns of Urumqi’s Population

In this paper, an approach to simulate the spatial dis- tribution of urban population is proposed using urban land use and population statistical data through the geographical information systems (GIS). Then, the spatial population distribution of Urumqi as a case is simulated by the approach mentioned above and its varying patterns are analyzed by the raster population surface. As a result, producing raster population surface is more accurate and natural than the traditional choropleth map of population density. Concerning the spatial population distribution of Urumqi, the population density declines from south to north and the population distribution mainly presents "T-type", the population distribution presents multi-centre agglomeration and the population distribu- tion of the districts shows different features. The population den- sity varies significantly with the increase in the distance from central business district (CBD). Finally, it is found in this paper that the development history of districts, terrain and traffic road are main factors that have an influence Urumqi’s population dis- tribution. This paper tries to provide more accurate population data for the plan and management of urban land, traffic and public facilities in order to enrich the researches on urban population distribution.

Quantum Information Transfer from a Double Quantum Dot System to a Cavity Field

In this paper, we propose a scheme to realize quantum information transfer from a double quantum dot （DQD） system to a quantized cavity field. The DQD and the cavity field are treated as a two-state charge qubit and a continuous-variable system, respectively. It is shown that quantum information encoded in the two-state DQD system can be transferred to quantum states of the cavity field with a continuous-variable basis through appropriate projective measurements with respect to the DQD.

RESPONSES OF WETLAND ECO SECURITY TO LAND USE CHANGE IN WESTERN JILIN PROVINCE, CHINA

By the use of the software of ARCGIS, dynamic changes of the landscape elements, landscape structure, conversion processes of the landscape gradients and the responses of wetland eco-security to land use/cover changes (LUCC) in the western Jilin Province were studied from 1930 to 2000. The results show that the landscape elements of grassland, wetland, forestland and water area shrank rapidly, and wetlands underwent huge losses in the study period due to the conversion from wetland into arable land and grassland in large quantities. The responses of wetland eco-security to LUCC were inverse evolvement of wetland vegetation, loss of biodiversity, water deficiency in wetland ecosystem, the changes of the heterogeneity of wetlands and the fragmentation of the wetland habitats. Suggestions were given for protection of wetlands and the regional sustainable development.

Land-Cover Change Monitoring in Obuasi, Ghana： An Integration of Earth Observation, Geoinformation Systems and Stochastic Modelling

For over twenty years, Obuasi Municipality, Ghana, has experienced land-cover change arising from gold mining and urbanisation. This project quantified the land-cover changes that have taken place and projected likely future land-cover. An integration of EO （earth observation）, GIS （geographical information science） and Stochastic Modelling was examined. Post-classification Change Detection employed Landsat TM or ETM＋ images in 1986, 2002 and 2008. Subsequently, Markov Chain Analysis projected the land-cover distribution for 2020. Seven broad land-use and land-cover classes were identified and mapped, namely： built-up areas, mine sites tailing ponds barren land forestland farmland and rangeland. The results obtained for the 2008 to 2020 projection revealed a continuous expansion of built-up areas （1.63%）, mine sites （0.89%） and farmland （3.4%）, and a reduction of forestland （4.17%） and rangeland （2.59%）. Despite the advent of very high resolution satellite imagery, this use of EO and GIS technology focussed on low-cost and lower resolution satellite imagery, coupled with Markov Modelling and was found to be beneficial in describing and analysing land-cover change processes in the study area, and was hence potentially useful for strategic planning purposes.

Stability analysis and monitoring study of Jijia River landslide based on WebGIS

On the basis of in situ investigation and deformation monitoring of the Jijia River landslide （JJRL）, the rigid body limit equilibrium method and finite element method （FEM） were used to analyze the stability of the JJRL; the grey system theory method was applied to forecast the deformation trend of the JJRL; and the information system about the landslide deformation and monitoring, and forecasting systems based on the platform of the Web Geographical Information System （WebGIS） were developed, which can be used to analyze in situ monitoring data and predict the deformation of the landslide. The study results can be summarized as follows： （1） the JJRL is stable as a whole; the water content in the landslide has a great effect on its stability; （2） the developed Web Geographical Information System has realized many functions, including inputting, computing, inquiry, analyzing, and the function of forecasting; it has also realized the functions of distance data management, analysis, and forecasting based on the WebGIS; （3） the information resource can be shared by the WebGIS developed all over the world.

Enhanced multiple access schemes for future broadband satellite communications

A new structure of next generation integrated communication system was proposed, which is composed of space segment based on satellites and terrestrial segment. Moreover, the characteristics of enhanced multiple access schemes based on orthogonal frequency division multiplexing (OFDM) technique were analyzed for satellite links. However, OFDM is a doubtful candidate as its higher peak-to-average power ratio (PAPR) that causes the distortion of high power amplifier (HPA). Furthermore, different schemes were evaluated and compared in terms of the HPA nonlinearity and the link level performance in detail. And the pilot-aided channel estimation and equalization techniques were also considered for analyzing the problem. Simulation results show that the bit error rate (BER) and block error rate (BLER) performance of orthogonal frequency division multiple access (OFDMA) outperforms that of single carrier-frequency division multiple access (SC-FDMA) for the satellite links in the proposed structure, though discrete Fourier transform-spread OFDM DFT-S OFDM has low PAPR, especially the BER performance of OFDMA is 3.6 dB larger than that of SC-FDMA at the target BER.

Signal pre-processing method and application design of edge nodes for distributed electromechanical system

A signal pre-processing method based on optimal variational mode decomposition(OVMD)is proposed to improve the efficiency and accuracy of local data filtering and analysis of edge nodes in distributed electromechanical systems.Firstly,the singular points of original signals are eliminated effectively by using the first-order difference method.Then the OVMD method is applied for signal modal decomposition.Furthermore,correlation analysis is conducted to determine the degree of correlation between each mode and the original signal,so as to accurately separate the real operating signal from noise signal.On the basis of theoretical analysis and simulation,an edge node pre-processing system for distributed electromechanical system is designed.Finally,by virtue of the signal-to-noise ratio(SNR)and root-mean-square error(RMSE)indicators,the signal pre-processing effect is evaluated.The experimental results show that the OVMD-based edge node pre-processing system can extract signals with different characteristics and improve the SNR of reconstructed signals.Due to its high fidelity and reliability,this system can also provide data quality assurance for subsequent system health monitoring and fault diagnosis.