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Atmospheric correction of HJ-1A/B CCD images over Chinese coastal waters using MODIS-Terra aerosol data

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Science China(Technological Sciences) 2010年第S1期53卷 191-195页

作者： TIAN LiQiao 1,LU JianZhong 1,CHEN xiaoLing 1,2,3.YU ZhiFeng 1,xiAO JingJing 1,QIU Feng 1 & ZHAO xi 1 1 {3. key laboratory of Information Engineering in Surveying,Mapping and Remote Sensing,Wuhan university,Wuhan 43.079,China 2key laboratory of Poyang Lake Wetland and Watershed Research,Ministry of Education,Jiangxi Normal university,Nanchang 3.0022,China 3.The key laboratory of Poyang Lake Environment and Resource Utilization,Ministry of Education,Nanchang university,Nanchang 3.003.,China 1. state key laboratory of Information Engineering in Surveying Mapping and Remote Sensing Wuhan University Wuhan 430079 China 2. key laboratory of Poyang Lake Wetland and Watershed Research Ministry of Education Jiangxi Normal University Nanchang 330022 China 3. The key laboratory of Poyang Lake Environment and Resource Utilization Ministry of Education Nanchang University Nanchang 330031 China

This paper demonstrates an atmospheric correction method to process HJ-1A/B CCD images over Chinese coastal waters with the aid of MODIS-Terra aerosol *** on the assumption of zero water-leaving radiance at the two near-infrared (NIR)bands or the shortwave infrared(SWIR)bands,the atmospheric aerosol optical depth(AOD)is firstly retrieved from MODIS-Terra with a simple extension of the NIR-SWIR combined atmospheric correction approach embedded in SeaDAS (SeaWiFS data analysis system).Then the"turbid"and"non-turbid"waters are separated by the turbid water *** probability of AOD at 551 nm band is derived based on the NIR information over"non-turbid"waters and FLAASH model is selected to do the atmospheric correction of the HJ-1A/B CCD imagery using the AOD values of highest probabilities as ***,according to the histogram of the AOD distribution at 551 nm band,the studied turbid water area is divided into several blocks and HJ-1A/B CCD imagery is corrected with the corresponding AOD values displayed with the highest frequency in each *** method has been applied to several HJ-1A/B images over Chinese coastal waters and validated by synchronous in-situ *** results have shown that this method is effective in the atmospheric correction process of HJ-1A/B CCD images for ocean color remote sensing study and application in the coastal waters.

关键词： ocean color remote sensing atmospheric correction turbid coastal waters HJ-1A/B MODIS

Impacts of electrochemical disinfection on the viability and structure of the microbiome in secondary effluent water

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Frontiers of Environmental Science & Engineering 2024年第5期18卷 73-83页

作者： Marvin Yeung Lan Tian Yuhong Liu Hairong Wang Jinying xi Environmental Simulation and Pollution Control state key Joint laboratory School of EnvironmentTsinghua UniversityBeijing100084China Graduate School at Shenzhen Tsinghua UniversityShenzhen518055China

Electrochemical disinfection(ECD)is a promising disinfection technique for wastewater reclamation;however,the impacts of ECD on the microbiome in secondary effluent wastewater remain *** this study,Propidium monoazide-qPCR(PMA-qPCR)and the plate count method were used to evaluate the inactivation performance,and the PMA-16S rRNA gene sequences of living cells were targeted to study the microbiome.A discrepancy was found between PMA-qPCR and the plate count method in the evaluation of cell count,with increases of 1.5 to 2.2 orders of magnitude in the disinfection rate after 150 s of ***,the cell count recovered and occasionally exceeded original levels within 3.d after *** was suppressed after ECD,but the microbiome after 150 s disinfection retained a higher level of evenness and stability in the community with a median Shannon index(>3.7).Pathogenic bacteria remained high in relative abundance even after 150 s of 25 V disinfection,but the biofilm-forming population was effectively suppressed by *** co-occurrence network revealed a centralized and fragile network as disinfection persisted,demonstrating the destabilizing effects of ECD on the *** pathways for cell membrane synthesis and organic compound degradation were enriched after *** reaction of the microbiome after ECD was similar to other disinfection techniques in terms of community structure.

关键词： Electrochemical disinfection Secondary effluent Microbiome

基于直接链路协议的无线局域网络及其安全策略

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计算机工程与应用 2004年第23期40卷 131-134页

作者：李晓辉刘乃安刘晓军西安电子科技大学综合业务网国家重点实验室西安710071 西安电子科技大学雷达信号处理国家重点实验室西安710071

无线局域网(WLAN)的直接链路协议(PLD)是WLAN服务质量(QoS)的重要组成部分。文章首先描述了WLAN的发展及在无线通信领域的重要作用;接着研究分析了WLAN网络中的新型协议———直接链路协议(DLP)的工作原理;在研究了无线局域网安全协议之... 详细信息

无线局域网(WLAN)的直接链路协议(PLD)是WLAN服务质量(QoS)的重要组成部分。文章首先描述了WLAN的发展及在无线通信领域的重要作用;接着研究分析了WLAN网络中的新型协议———直接链路协议(DLP)的工作原理;在研究了无线局域网安全协议之后,针对DLP协议带来的安全问题,提出了基于DLP协议的安全算法及认证机制;该方法不仅保证了直接链路数据通信的安全性,同时可以减少接入点(AP)对移动主机过多管理带来的开销以及信息传输的时延。

关键词：直接链路协议 DLP WLAN 安全算法认证机制无线局域网安全策略

Selective adsorption of tetracycline by β-CD-immobilized sodium alginate aerogel coupled with ultrafiltration for reclaimed water

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Chinese Journal of Chemical Engineering 2024年第4期68卷 27-34页

作者： xi Quan Jun Zhang Linlin Yin Wei Zuo Yu Tian state key laboratory of Urban Water Resource and Environment(SKLUWRE) School of EnvironmentHarbin Institute of TechnologyHarbin 150090China

In this work,a novel composite material based on β-cyclodextrin-immobilized sodium alginate aerogel(β-CD/NaAlg) was developed utilizing cross-linker of epichlorohydrin and applied as an adsorbent to remove tetracycline antibiotics from reclaimed wastewater.A series of characterizations were utilized to confirm the successful synthesis of the adsorbent and this β-CD/NaAlg presented a three-dimensional network at the nanoscale or *** optimal conditions(pH=4,t=8 h,β-CD:NaAlg=9,adsorbent dosage = 1.5 g·L-1),the maximum removal rate of β-CD/NaAlg to tetracycline was 70%.The adsorption behavior of tetracycline on β-CD/NaAlg conformed to the Freundlich isotherm model(R2=0.9977) and the pseudo-second-order kinetic model(R^(2)=0.9993..Moreover,the adsorbent still removed 55.3. of tetracycline after five ***,the adsorbent was integrated with ultrafiltration to adsorb tetracycline antibiotics from simulated reclaimed wastewater,and the removal rate of tetracycline reached 78.9% within 2 *** existence of Cr(Ⅵ) had a negligible impact on tetracycline removal,while the presence of humic acid exhibited a promoting *** possible adsorption mechanisms were also elucidated through X-ray photoelectron spectroscopy and density functional theory *** summary,β-CD/NaAlg represents an environmentally friendly,efficient,and sustainable adsorbent for removing tetracycline antibiotics from reclaimed water.

关键词： b-CD/NaAlg aerogel Covalent grafting Tetracycline antibiotics Ultrafiltration Selective adsorption Reclaimed water

Transport network and flow mechanism of shallow ore-bearing magma in Tongling ore cluster area

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Science China Earth Sciences 2006年第4期49卷 397-407页

作者： DENG Jun1,2, WANG Qingfei1,2 , HUANG Dinghua3., WAN Li4, YANG Liqiang1,2 & GAO Bangfei1,2 1. state key laboratory of Geological Processes and Mineral Resources, China {3. of Geosciences, Beijing 100083. China 2. key laboratory of Lithosphere Tectonics and Lithoprobing Technology of Ministry of Education, China {3. of Geo- sciences, Beijing 100083. China 3. Faculty of Earth Sciences, China {3. of Geosciences, Wuhan 43.074, China 4. School of Mathematics and Information Science, Guangzhou {3., Guangzhou 510405, China 1. state key laboratory of Geological Processes and Mineral Resources China University of Geosciences Beijing 100083 China 2. key laboratory of Lithosphere Tectonics and Lithoprobing Technology of Ministry of Education China University of Geosciences Beijing 100083 China 3. Faculty of Earth Sciences China University of Geosciences Wuhan 430074 China 4. School of Mathematics and Information Science Guangzhou University Guangzhou 510405 China

Abundant studies revealed that shallow intrusions of the Yanshanian epoch resulted in the mass mineralization of the Tongling region. Various evidences showed there existed a concealed magma chamber at ?10 km depth in the middle part of this region during Yanshanian epoch, from which the ore-forming magma was generated and then transported to the superficial layer. Yet the transport network and flow mechanism of the shallow ore-bearing magma, the key problem associ- ated with ore-forming process, was relatively little focused on. Integrate analysis of structural me- chanics, statistical fractal and geological facts suggested that NE trending high-angle fold-related thrust faults and the tessellated basement ones served as the main pathways for the shallow magma’s transporting, moreover, the saddle void spaces among adjacent strata in the folds upon this fault system provided the place for magma’s emplacement. So the folds in the upper part and faults in the lower part of the upper crust constituted the fluid’s transport and emplacement network. During the deformation of geologic body with multi-layer structure, the layers in the upper part tended to fold when received the jacking stress from the lower part, while the lower one inclined to fault undergoing loads of the upper part. And the producing probability of this structure assemblage was highly in- creased in the condition, such as in the Tongling area, that the mechanic rigidity of the lower layers was stronger than that of the upper ones. For the pre-existence of fluid-conducting network, the top magma with high volatile in the magma chamber transported rapidly to the superficial layer in dyking pattern, located in the void spaces of folds, filled and reconstructed them. The sudden drop of pres- sure caused the fluid unmixing from the magma and mass ore-forming elements concentration. Pulse activity of the dyking may be the principal reason why magmatic bodies in the Tongling area were spatially-temporally con

关键词： Tongling, structural network, magma intrusion, fractal, dyke.

Cyclic-delay time-reversal space-time block codes for single-carrier transmission with frequency-domain decision-feedback equalization

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Science China(Information Sciences) 2011年第9期54卷 1905-1915页

作者： FENG Ang,YIN QinYe & WANG HuiMing MOE key laboratory for Intelligent networks and network Security,xi’an Jiaotong {3.,xi’an 710049,China 1. MOE key laboratory for Intelligent networks and network Security Xi’an Jiaotong University Xi’an 710049 China

Transmit diversity is an important multiple-input multiple-output (MIMO) approach to improve the transmission reliability;however,it is usually designed with maximum-likelihood *** this paper,we investigate a simple transceiver structure for single-carrier MIMO systems,in which the cyclic-delay time-reversal space-time block code (CDTR-STBC) is employed at the transmitter,and the frequency-domain decision-feedback equalization (FD-DFE) is used at the *** separate the transmit antennas into two groups,and then,encode the groups by STBC and cyclically delay the data streams within each *** processing can mitigate the impact of error-propagation and reduce the signal-to-noise ratio (SNR) loss when FD-DFE is employed,in which SNR is defined as the ratio of the received signal power over the noise power at each receive *** support our proposal,this paper also provides the performance analysis of *** is shown that the proposed scheme can achieve full diversity and full transmission rate for a MIMO system employing arbitrary ***,it has considerable performance improvement over the existing schemes.

关键词： single-carrier frequency-domain equalization cyclic delay space-time block code diversity order

Vision navigation algorithm for mine agent based on quaternion

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中国有色金属学会会刊：英文版 2011年第S3期21卷 610-615页

作者： LI Ke-zhao1, 4, LEI Wei-wei1, 2, GUO Zeng-zhang1, 2, WU Li-xin3. ZHANG Qin4 1. School of Survey and Land Information Engineering, Henan Polytechnic university, Jiaozuo 454003. China 2. key {3. of Mine Spatial Information Technologies of state Bureau of Surveying and Mapping, Henan Polytechnic university, Jiaozuo 454003. China 3. College of Resources and Civil Engineering, Northeastern university, Shenyang 110819, China 4. College of Geology Engineering and Geomatics, Chang’an university, xi’an 710054, China [a] School of Survey and Land Information Engineering Henan Polytechnic University Jiaozuo 454003 China [b] key laboratory of Mine Spatial Information Technologies of state Bureau of Surveying and Mapping Henan Polytechnic University Jiaozuo 454003 China [c] College of Resources and Civil Engineering Northeastern University Shenyang 110819 China [d] College of Geology Engineering and Geomatics Chang'an University Xi'an 710054 China

Autonomous relative navigation is the key technology in mining or rescuing. On the basis of mine requirement and the theories of machine vision, an autonomous relative navigation algorithm for mine agent based on quaternion was proposed. In rotation transformation, this algorithm was represented by using quaternion. Because the Jacobi matrix of this method is lower than that of Hall algorithm, the calculation efficiency is improved by using this algorithm. The results of these experiments show that the computation burden of this algorithm based on quaternion is about half that of Hall algorithm. This algorithm based on quaternion is improved as a valid way to solve the problem of mine real-time navigation.

关键词： quaternion mine agent vision navigation

Wireless Mesh network and IEEE 802 Standards

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ZTE Communications 2008年第2期6卷 7-10页

作者： Chen Linlin, Liu Naian (state key Lab of integrated Service {3.s , xidian university, xi’an 710071, China )

Although the wireless broadband access system is developing rapidly, its development is limited due to some disadvantages , such as small capacity of bandwidth and small coverage . The Wireless Mesh network (WMN) is one of the important technologies for 'last mile 'broadband wireless access . The WMN can integrate with multiple wireless systems , such as Wireless Local Area network (WLAN), Wireless Personal Area network (WPAN), and Wireless Metropolitan Area network (WMAN), to improve the performance of the wireless network and enlarge the coverage range . With the wide applications of the WMN, the IEEE 802 standard group is devoted to promoting the development of the WMN technology and establishing the related technical standards . At present, WMN standards have appeared in IEEE 802.11s , 802.15, 802.16, and 802.20.

关键词： Mesh WMN IEEE Wireless Mesh network and IEEE 802 Standards

Surface pollen and modern vegetation in Southern xinjiang,China

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Science China Earth Sciences 2024年第2期67卷 510-530页

作者： Yun ZHANG Lixin CHEN Yaoyao xi Zhaochen KONG xianguo QIAO state key laboratory of Black Soils Conservation and Utilization Northeast Institute of Geography and AgroecologyChinese Academy of SciencesChangchun130102China Institute of Botany Chinese Academy of SciencesBeijing100093China key laboratory of Cenozoic Geology and Environment Institute of Geology and GeophysicsChinese Academy of SciencesBeijing100029China university of Chinese Academy of Sciences Beijing100049China School of Geosciences and Resources China University of Geosciences(Beijing)Beijing100083China

The study of modern pollen,and vegetation can improve the accuracy of paleoenvironmental reconstruction based on fossil pollen data.A total of 188 pollen surface samples were collected from Southern xinjiang(3.°00’–43.00’N,74°00’–94°00’E)in China,with an elevation range of 888–453. *** pollen and vegetation were studied in the northern region of the Kunlun Mountains and the southern region of the Tianshan *** results showed that the surface pollen assemblages on the southern slope of the Tianshan Mountains(3.3.–1124 m)were divided into three pollen zones,namely,montane steppe,montane desert steppe,and montane *** zones were dominated by Artemisia,Chenopodiaceae,and Ephedra *** surface pollen assemblages in the eastern Pamir Plateau(453.–1287 m)could be divided into alpine meadow,montane desert steppe,and montane desert zones,which were predominantly characterized by Artemisia,Chenopodiaceae,and Asteraceae ***,the Southern Tarim Basin(3.48–888 m)comprised montane desert steppe and montane desert zones,which was dominated by Artemisia and Chenopodiaceae *** geographic distribution of the surface pollen sites obtained using ArcGIS,the R-value,and Pearson correlation analyses indicated that the over-represented Picea and Pinus pollen were of external origin and were transported by wind,water(rivers),and ice(glacier movement).Over-representation of Ephedra and Nitraria pollen was mainly distributed in the montane desert and desert steppe zones,*** from Chenopodiaceae and Artemisia were over-represented and broadly distributed across Southern *** pollen was concentrated in areas with walnut trees,strongly indicating the presence of local parent *** to the Hybrid Singleparticle Lagrangian integrated Trajectory model,more Pinus pollen was transported to the Pamir region by external airflows during spring and summer,resulting in its higher surface pollen *** elucidating t

关键词： Surface pollen Vegetation Distribution Picea Southern xinjiang