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Reconstruction of Smoke Plume Concentration Peaks Based on Modified MAX-DOAS Tomography

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Chinese Journal of Chemical Physics 2015年第6期28卷 -页

作者： Min-hong Wei Min-ming Tong su-wen li School of Physics and Electronic Information Huaibei Normal University Huaibei 235000 ChinaSchool of Information and Electrical Engineering China University of Mining and Technology Xuzhou 221116 China School of Information and Electrical Engineering China University of Mining and Technology Xuzhou 221116 China School of Physics and Electronic Information Huaibei Normal University Huaibei 235000 China

Optical tomography system based on modified simultaneous iterative reconstruction technique is designed to real-time monitor spatial distribution and diffusion process of smoke plume in a power plant. Concentration profiles, rather than just a point value, of smoke plume concentrations are the goal of this method, and the tomography algorithm is analyzed. According to incomplete projection data in the process of reconstruction and exiting noise interference, the modified simultaneous iterative reconstruction technique (SIRT) is adopted to extract the information of the trace gas concentration by a fan beam scanning and is compared to the conventional SIRT. Three evaluation indexes show that the reconstruction effect is the best by choosing proper relaxation factor, which reduces the index d to 0.044 from 0.435 and reduces the index r to 0.044 from 0.376 for 5500 iterations. Hence, the modified algorithm performs better in estimating the shape of the plume, this method is used to process the measured spectra in field campaign, the reconstruction results and the measured data are basically consistent, which is further confirmed by the experimental results.

关键词： Reconstruction DOAS tomography Retrieval Modified simultaneous iterative reconstruction technique

Application of local polynomial estimation in suppressing strong chaotic noise

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Chinese Physics B 2012年第2期21卷 181-186页

作者： su li-Yun Ma Yan-Ju li Jiao-Jun School of Mathematics and Statistics Chongqing University of TechnologyChongqing 400054China School of Electronic Information and Automation Chongqing University of TechnologyChongqing 400054China

In this paper, we propose a new method that combines chaotic series phase space reconstruction and local polynomial estimation to solve the problem of suppressing strong chaotic noise. First, chaotic noise time series are reconstructed to obtain multivariate time series according to Takens delay embedding theorem. Then the chaotic noise is estimated accurately using local polynomial estimation method. After chaotic noise is separated from observation signal, we can get the estimation of the useful signal. This local polynomial estimation method can combine the advantages of local and global law. Finally, it makes the estimation more exactly and we can calculate the formula of mean square error theoretically. The simulation results show that the method is effective for the suppression of strong chaotic noise when the signal to interference ratio is low.

关键词： strong chaotic noise local polynomial estimation weak signal detection

Structure,optical,and magnetic properties of Mn-doped ZnO films prepared by sputtering

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International Journal of Minerals,Metallurgy and Materials 2010年第4期17卷 475-480页

作者： li-wei Wang Zheng Xu Fu-junZhang su-ling Zhao li-fang Lu Institute of Optoelectronics Technology Key Laboratory of Luminescence and Optical Information （Ministry of Education of China） Beijing Jiaotong University Beijing100044 China

The microstructural, optical, and magnetic properties and room-temperature photoluminescence （PL） ofMn-doped ZnO thin films were studied. The chemical compositions were examined by energy dispersive X-ray spectroscopy （EDS） and the charge state of Mn ions in the ZnO：Mn films was characterized by X-ray photoelectronic spectrometry （XPS）. From the X-ray diffraction （XRD） data of the samples, it can be found that Mn doping does not change the orientation of ZnO thin films. All the films prepared have a wurtzite structure and grow mainly along the c-axis orientation. The grain size and the residual stress were calculated from the XRD results. The optical transmittance of the film decreases with the increase of manganese content in ZnO. The room-temperature photoluminescence of the films shows that the in- tensity of near band energy （NBE） emission depends strongly on the Mn content. The hysteresis behavior indicates that the films with the Mn content below 9at% are ferromagnetic at room temperature.

关键词： ZnO magnetron sputtering ferromagnetism optical properties photoluminescence

Hybrid QoS-aware semantic web service composition strategies

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Science in China(Series F) 2008年第11期51卷 1822-1840页

作者： YANG FangChun su Sen li Zhen State Key Lab of Networking & Switching Beijing University of Posts & Telecommunications Beijing100088 China

Hybrid QoS model which consists of certain and uncertain expressions has strong power of semantic QoS description. For solving the hybrid QoS-aware semantic web service composition problem, this paper presents an Uncertain Multi-attribute decision making based Composition algorithm （UMC）. The UMC includes two parts. First, UMC-Core can be used to synthetically evaluate the hybrid service quality information. Second, UMC-DH （Distributed and Heuristic framework for UMC） aims at enhancing the run-time performance of UMC when the problem space increases. The simulation results show that the UMC has lower execution cost, higher approximation ratio and success ratio than other similar approaches.

关键词： quality of service (QoS) semantic web service service composition theory of uncertainties multi-attribute decision making theory heuristic algorithm

Iterative selection algorithm for service composition in distributed environments

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Science in China(Series F) 2008年第11期51卷 1841-1856页

作者： su Sen li Fei YANG FangChun State Key Laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications Beijing 100876 China

In service oriented architecture （SOA）, service composition is a promising way to create new services. However, some technical challenges are hindering the application of service composition. One of the greatest challenges for composite service provider is to select a set of services to instantiate composite service with end- to-end quality of service （QoS） assurance across different autonomous networks and business regions. This paper presents an iterative service selection algorithm for quality driven service composition. The algorithm runs on a peer-to-peer （P2P） service execution environment--distributed intelligent service execution （DISE）, which provides scalable QoS registry, dynamic service selection and service execution services. The most significant feature of our iterative service selection algorithm is that it can work on a centralized QoS registry as well as cross decentralized ones. Network status is an optional factor in our QoS model and selection algorithm. The algorithm iteratively selects services following service execution order, so it can be applied either before service execution or at service run-time without any modification. We test our algorithm with a series of experiments on DISE. Experimental results illustrated its excellent selection and outstanding performance.

关键词： web service quality of service (QoS) service selection algorithm distributed QoS registry

The kinematics of an untwisting solar jet in a polar coronal hole observed by SDO/AIA

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Research in Astronomy and Astrophysics 2012年第5期12卷 573-583页

作者： Hua-Dong Chen Jun Zhang su-li Ma College of Science China University of Petroleum Qingdao 266555 China Key Laboratory of Solar Activity National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China Harvard-Smithsonian Center for Astrophysics MA 02138 U 5A

Using the multi-wavelength data from the Atmospheric Imaging Assembly （AIA） onboard the Solar Dynamics Observatory （SDO） spacecraft, we study a jet occurring in a coronal hole near the northern pole of the sun. The jet presented distinct upward helical motion during ejection. By tracking six identified moving features （MFs） in the jet, we found that the plasma moved at an approximately constant speed along the jet＇s axis. Meanwhile, the MFs made a circular motion in the plane transverse to the axis. Inferred from linear and trigonometric fittings to the axial and transverse heights of the six tracks, the mean values of the axial velocities, transverse velocities, angular speeds, rotation periods, and rotation radii of the jet are 114 km s-1, 136 km s-1, 0.81° s-1, 452 s and 9.8 × 10^3 km respectively. As the MFs rose, the jet width at the corresponding height increased. For the first time, we derived the height variation of the longitudinal magnetic field strength in the jet from the assumption of magnetic flux conservation. Our results indicate that at heights of 1 × 10^4 -7 × 10^4 km from the base of the jet, the flux density in the jet decreases from about 15 to 3 G as a function of B = 0.5（R/R） - 1）-0.84 （G）. A comparison was made with other results in previous studies.

关键词： sun activity -- sun chromosphere -- sun magnetic fields -- sun flares -- sun rotation

Origin of the Zedang and Luobusa Ophiolites, Tibet

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Acta Geologica Sinica(English Edition) 2014年第2期88卷 669-698页

作者： BAO Peisheng su li WANG Jun ZHAI Qingguo Institute of Geology Chinese Academy of Geological Sciences Institute of Earth Sciences China University of Geosciences

The Zedang and Luobusa ophiolites are located in the eastern section of the Yalung Zangbo ophiolite belt,and they share similar geological tectonic setting and ***,an understanding of their origins is very important for discussion of the evolution of the Eastern Tethys *** is no complete ophiolite assemblage in the Zedang *** Zedang ophiolite is mainly composed of mantle peridotite and a suite of volcanic rocks as well as siliceous rocks,with some blocks of *** mantle peridotite mainly consists of Cpx-harzburgite,harzburgite,some lherzolite,and some dunite.A suite of volcanic rocks is mainly composed of caic-aikaline pyroclastic rocks and secondly of tholeiitic pillow lavas,basaltic andesites,and some boninitic rocks with a lower TiO2 content （TiO2 ＜ 0.6％）.The pyroclastic rocks have a LREE-enriched REE pattern and a liLE-enriched （compared to HFSE） spider diagram,demonstrating an island-arc *** tholeiitic volcanic rock has a LREE-depleted REE pattern and a liLE-depleted （compared to HFSE） spider diagram,indicative of an origin from *** boninitic rock was generated from fore-arc *** Luobusa ophiolite consists of mantle peridotite and mafic-ultramaflc cumulate units,without dike swarms and volcanic *** mantle peridotite mainly consists of dunite,harzburgite with low-Opx （Opx ＜ 25％）,and harzburgite （Opx ＞ 25％）,which can be divided into two facies *** upper is a dunite-harzburgite （Opx ＜ 25％） belt,containing many dunite lenses and a large-scale chromite deposit with high Cr203; the lower is a harzburgite （Opx ＞25％） belt with small amounts of dunite and *** Luobusa mantle peridotite exhibits a distinctive vertical zonation of partial melting with high melting in the upper unit and low melting in the *** mantle peridotites are highly depleted,with a characteristic U-shaped REE pattern peculiar to fore-arc *** Luobusa cumulates are composed of wehrlite and olivine-pyroxe

关键词： Zedang ophiolite Luobusa ophiolite MORB island arc fore-arc extension subduction initiation

Study on the Tectonic Setting for the Ophiolites in Xigaze, Tibet

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Acta Geologica Sinica(English Edition) 2013年第2期87卷 395-425页

作者： BAO Peisheng su li WANG Jun ZHAI Qingguo Institute of Geology Chinese Academy of Geological Sciences Institute of Earth Sciences China University of Geosciences

The Xigaze ophiolite is located in the middle section of the Yarlung Zangbo River ophiolite belt and includes a well-preserved sequence section of seven ophiolite blocks. The relatively complete ophiolitic sequence sections are represented by Jiding, Dejixiang, Baigang, and Dazhuqu ophiolites and consist of three-four units. The complete ophiolite sequence in order from the bottom to top consists of mantle peridotite, cumulates, sheeted sill dike swarms, and basic lavas±radiolarian chert. These cumulates are absent in the remaining blocks of Dejixiang and Luqu. The age of radiolaria in the radiolarian chert is Late Jurassic-Cretaceous. The basalt and ultramafic rock of the ophiolite also are overlaid by Tertiary liuqu conglomerate, which contains numerous pebble components of ophiolite, indicating that the Tethys Ocean began to close at the end of Cretaceous Period. The isotopic data of gabbro, diabase, and albite granite in the Xigaze ophiolite are approximately 126-139 Ma, which indicates that the ophiolite formed in the Early Cretaceous. The K-Ar age of amphibole in garnet amphibolite in the ophiolite melange is 81 Ma, indicating that tectonic ophiolite emplacement occurred at the end of Late Cretaceous. Research in petrology, petrological chemistry, mineralogy, and geochemistry of volcanic rocks and dikes of the Xigaze ophiolite indicate the following characteristics：（1） They are mainly composed of basalt, basaltic andesite, dolerite, and diabase and are characterized by high TiO2 （0.7-1.47%）, low MgO （mostly less than 8%）, and low SiO2 （mostly less than 53%）. （2） The volcanic rocks and dikes of the Xigaze ophiolite show light rare earth element （LREE）-depleted rare earth element （REE） patterns. （3） The spider diagrams of the volcanic rocks and dikes of the Xigaze ophiolite exhibit liLE depletion relative to high-field-strength element （HFSE） patterns with left oblique features. （4） No protogenetic olivine and clinoenstatite was detected. （5） Some dikes show lo

关键词： MORB boninite series rocks forearc extention subduction initiation Xigaze ophiolite

Petrological, geochemical and chronological constraints for the tectonic setting of the Dongco ophiolite in Tibet

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Science China Earth Sciences 2007年第5期50卷 660-671页

作者： BAO PeiSheng XIAO XuChang su li WANG Jun Institute of Geology Chinese Academy of Geological SciencesBeijing 100037China Experimental Center China University of GeologyBeijing 100029China

The Dongco ophiolite occurred in the middle-western segment of the Bangong-Nujiang suture zone. The thickness of the ophiolite suite is more than 5 km, which is composed, from bottom to top, of the mantle peridotite, mafic-ultramafic cumulates, basic sills (dykes) and basic lava and tectoni- cally emplaced in Jurassic strata (Mugagongru Group). The Dongco cumulates consist of dunite- troctolite-olivine-gabbro, being a part of DTG series of mafic-ultramafic cumulates. The basic lavas are characterized by being rich in alkali (Na2O+ K2O), TiO2, P2O5 and a LREE-rich type pattern dip- ping right with [La/Yb]=6.94―16.6 as well as a trace elements spider-diagram with normal anomaly of Th, Nb, Ta, Hf. Therefore, the Dongco basic lavas belong to ocean-island basalt (OIB) and dis- tinctly differ from mid-ocean ridge basalt (MORB) and island-arc basalt (IAB) formed in the plate convergence margin. The basic lavas have higher 87Sr/86Sr (0.704363―0.705007), lower 143Nd/144Nd (0.512708―0.512887) and εNd(t ) from +2.7―+5.8, indicating that they derive from a two-components mixing mantle source of depleted mantle (DM) and enriched mantle (EMI). From above it is ready to see that the Dongco ophiolite forms in oceanic island (OIB) where the mantle source is replaced by a large amount of enriched material, therefore it distinctly differs from these ophiolites formed in island-arc and mid-oecan ridge. Newly obtained SHRIMP U-Pb dating for zircon of the cumulate troctolite is 132 ± 3 Ma and whole-rock dating of ^(39)Ar/^(40)Ar for the basalt is 173.4 ± 2.7 Ma and 140.9 ± 2.8 Ma, indicating that the Dongco ophiolite formed at Early Cretaceous and the middle-western segment of the Bangong-Nujiang oceanic basin was still in the developing and evolving period at Early Cretaceous.

关键词： Dongco ophiolite geochemistry SHRIMP U-Pb dating for zircon whole-rock dating of 39Ar/40Ar Bangong-Nujiang suture zone