Application of PCA Numalgorithm in Remote Sensing Image Processing

A numerical algorithm of principal component analysis (PCA) is proposed and its application in remote sensing image processing is introduced: (1) Multispectral image compression;(2) Multi-spectral image noise cancellation;(3) Information fusion of multi-spectral images and spot panchromatic images. The software experiments verify and evaluate the effectiveness and accuracy of the proposed algorithm.

Integration of Enterprise Resource Planning System Based on SOAP

While the enterprise resource planning (ERP) systems become more and more complex, the traditional tools such as DCOM, CORBA or EJB encounter more difficulties than before especially when heterogenous and distributed environment and multiple companies are involved. The newly born international specification SOAP brings a new solution to ERP because of its simplicity and high extensibility. This paper analyses the techniques to extend basic SOAP to implement ERP system. The techniques, including data envelope, dynamically and loosely coupled remote process calling (RPC), support to the multiple communication protocol, and security and performance improvement, greatly enhance the ability of basic SOAP and make it capable to accomplish the integration task in large scale ERP systems. All the techniques we discusse here are successfully utilized in the ERP system in the Three Gorge Cascade Dispatch Center of China Three Gorge Project Corporation.

Advances in spaceborne hyperspectral remote sensing in China

With the maturation of satellite technology,Hyperspectral Remote Sensing(HRS)platforms have developed from the initial ground-based and airborne platforms into spaceborne platforms,which greatly promotes the civil application of HRS imagery in the fields of agriculture,forestry,and environmental monitoring.China is playing an important role in this evolution,especially in recent years,with the successful launch and operation of a series of civil hyper-spectral spacecraft and satellites,including the Shenzhou-3 spacecraft,the Gaofen-5 satellite,the SPARK satellite,the Zhuhai-1 satellite network for environmental and resources monitoring,the FengYun series of satellites for meteorological observation,and the Chang’E series of spacecraft for planetary exploration.The Chinese spaceborne HRS platforms have various new characteristics,such as the wide swath width,high spatial resolution,wide spectral range,hyperspectral satellite networks,and microsatellites.This paper focuses on the recent progress in Chinese spaceborne HRS,from the aspects of the typical satellite systems,the data processing,and the applications.In addition,the future development trends of HRS in China are also discussed and analyzed.

The 2020–2021 prolonged La Niña evolution in the tropical Pacific

The evolution of sea surface temperature(SST)in the tropical Pacific during 2020–2021 indicates a second-year cooling in late 2021 again,following the 2020 La Niña event.Its physical explanations are still lacking,and there is a clear need to understand the underlying processes involved.Observational data and reanalysis products are used to describe the characteristics and spatiotemporal evolution of upper-ocean thermal anomalies;an intermediate coupled model(ICM)is also used to perform numerical experiments to confirm these observation-based inferences.The evolution of subsurface thermal anomalies is critically important to that of SST in the central-eastern equatorial Pacific;the effects of the former on the latter can be well represented by the temperature of subsurface waters entrained into the mixed layer(Te),a field that reflects a subsurface forcing on SST.The SST evolution is sensitively dependent on the intensities of the local effect associated with Te anomalies in the eastern equatorial Pacific and the remote effect associated with subsurface anomalies from the western Pacific.During early-and mid-2021,a competition was present between these local and remote effects associated with Te anomalies.When the remote warming effect dominates the local cooling effect,the cold SST condition in the east is likely to turn into neutral and warm conditions;otherwise,it tends to continue.In addition,the negative Te anomalies were sustained and enhanced by off-equatorial processes due to equatorial wave reflections at the eastern boundary associated with the 2020 La Niña event.The SST evolution in mid-2021 corresponded to a situation in which the warming effect associated with positive subsurface thermal anomalies from the west were not strong enough to counteract the local cooling effect associated with negative anomalies in the east.In due course,cold SST anomalies in the east developed again and the second-year cooling reoccurred in late 2021,with a turning point in June 2021.Modeling experiments support these arguments and indicate that the intensity of subsurface thermal effect on SST,as represented by Te anomalies,needs to be adequately depicted for coupled models to capture the 2021 second-year cooling conditions in the tropical Pacific.