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Journal of Systems Engineering and Electronics 2009年第1期20卷 13-19页

作者： Tan Xiaogang wei Ping Li liping School of Electronic Engineering Univ. of Electronic Science and Technology of China Chengdu 610054 P. R. China

The Radon-ambiguity transform （RAT）, although efficient for detecting the linear frequency modulated signals （LFMs）, is troubled by the energy accumulation of noise in low signal-to-noise ratio （SNR）. A secondorder difference （SOD） method is proposed to treat with this problem. In the SOD method, the optimal search step and difference step are derived from the LFM rate resolution formula. The sharpness of the peaks of RAT is measured by curvature, and the sharpness, but not the magnitude of the peaks, is used to detect the LFMs. The SOD method removes the noise energy accumulation and reserves the drastically changing components integrally; thus, it improves the detection probability of LFMs in low SNR. The expected performance of the new method is verified by 100 Monte Carlo simulations.

关键词： linear frequency modulated signals Radon-axnbiguity transform detection probability low signal-to-noise ratio.

Photoinduced toxicity single and binary mixtures of four polycyclic aromatic hydrocarbons to the marine diatom Skeletonema costatum

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Acta Oceanologica Sinica 2007年第6期26卷 41-50页

作者： MENG wei WANG liping ZHENG Binghui River and Coastal Environment Research Center Chinese Research Academy of Environmental Sciences Beijing 100012 China

Diatom Skeletonema costatum Cleve is one of the main predominant phytoplankton species in the Changjiang Estuary in China. In order to provide some basic information for future assessment of the potential risk on phytoplankton communities in this estuary caused by polycyclic aromatic hydrocarbons（ PAHs）, this alga was selected as a representative to investigate the photoinduced toxicity of PAHs, in single and mixture. Four PAHs including three-ring phenanthrene and anthracene, four-ring fluoranthene and pyrene were tested in the laboratory. The single toxicity of each PAH on this microalga was compared with and without the simulated solar UV radiation. The results showed that this microalga was sensitive to PAH＇ s photoinduced toxicity. Ratios of the 72 h median effect concentration obtained for fluorescent and UV light tests were about 8.4 for phenanthrene, 13.0 for anthracene, 6. 5 for fluoranthene, and 5.7 for pyrene, indicating that UV light enhanced the PAH toxicity to this alga significantly. Under the fluorescent radiation （lacking UV ）, the dose-response curves based on chemical concentrations revealed that the order of toxic strength was fluoranthene greater than pyrene greater than anthracene greater than phenanthrene; while under the UV radiation （476 μW/cm^2 for UVA, 6.5 μW/cm^2 for UVB） it became fluoranthene approximately equaling anthracene greater than pyrene greater than phenanthrene, indicating that the UV light also changed its relative toxicity to this alga. The photoinduced toxicity of PAHs to the marine diatom S. costatum might be a synergistic effect of photosensitization reactions （ e. g. , generation of singlestate oxygen） and photomodification （photooxidation and/or photolysis）. The combined effects of six binary mixtures on the marine diatom S. costatum were investigated using the additive-index method. Four binary-mixtures （ phenanthrene plus anthracene ; phenanthrene plus pyrene ; anthracene plus fluoranthene ; anthracene plus pyrene） we

关键词： marine diatom polycyclic aromatic hydrocarbons phototoxicity combined toxicity

Multi-fluid Eulerian simulation of mixing of binary particles in a gas-solid fluidized bed with a cohesive particle-particle drag model

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Particuology 2020年第2期18卷 95-104页

作者： liping wei Guodong Jiang Haipeng Teng Jun Hu Jianbo Zhu School of Chemical Engineering Northwest UniversityChemical Engineering Research Center of the Ministry of Education for Advanced Use Technology of Shanbei Energyand Shaanxi Research Center of Engineering Technology for Clean Coal ConversionXi'an 710069ShaanxiChina

A particle-particle(p-p)drag model is extended to cohesive particle flow by introducing solid surface energy to characterize cohesive collision energy *** effects of the proportion of cohesive particles on the mixing of binary particles were numerically investigated with the use of a Eulerian multiphase flow model incorporating the p-p drag *** bed expansion,mixing,and segregation of Geldart-A and C particles were simulated with varying superficial velocities and Geldart-C particle proportions,from which we found that the p-p drag model can reasonably predict bed expansion of binary *** segregation types of jetsam-mixture-flotsam and mixture-flotsam processes were observed during the fluidization processes for the Geldart-A and C binary particle *** mixing processes of the binary particle system can be divided into three scales:macro-scale mixing,meso-scale mixing,and micro-scale *** a constant superficial velocity the optimal mixing was observed for a certain cohesive particle proportion.

关键词： Fluidization Cohesive particle Particle-particle drag model Mixing index Binary particles

Improvement on polynomial Wigner-Ville distribution for detecting higher-order polynomial phase signal

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Journal of Systems Engineering and Electronics 2009年第2期20卷 234-240页

作者： Tan Xiaogang wei Ping Li liping School of Electronic Engineering Univ. of Electronic Science and Technology of China Chengdu d10054 P. R. China

To detect higher order polynomial phase signals （HOPPSs）, the smoothed-pseudo polynomial Wigner-Ville distribution （SP-PVCVD）, an improved version of the polynomial Wigner-Ville distribution （PVCVD）, is presented using a separable kernel. By adjusting the lengths of the functions in the kernel, the balance between resolution retaining and interference suppressing can be adjusted conveniently. The proposed method with merits of interference terms reduction and noise suppression can provide time frequency representation of better readability and more accurate instantaneous frequency （IF） estimation with higher order SP-PVfVD. The performance of the SP-PWVD is verified by computer simulations.

关键词： signal processing polynomial Wigner-Ville distribution polynomial phase signal instantaneous frequency estimation

Benthic microbial biogeography along the continental shelf shaped by substrates from the Changjiang River plume

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Acta Oceanologica Sinica 2022年第1期41卷 118-131页

作者： Yongjun wei Shan Jiang Lingmin Tian liping wei Jie Jin Juan Severino Pino Ibanhez Yan Chang Xiaodao wei Ying Wu Key Laboratory of Advanced Drug Preparation Technologies of Ministry of Education School of Pharmaceutical SciencesZhengzhou UniversityZhengzhou 450001China State Key Laboratory of Estuarine and Coastal Research East China Normal UniversityShanghai 200241China Department of Food Science and Engineering Jinan UniversityGuangzhou 510632China Key Laboratory of Vegetation Restoration and Management of Degraded Ecosystems South China Botanical GardenChinese Academy of SciencesGuangzhou 510650China School of Natural Sciences Trinity College DublinDublin 2Ireland Instituto de Investigacions Marinas Consejo Superior de Investigaciones CientificasVigo 36208Spain Institute of Eco-Chongming East China Normal UniversityShanghai 202162China

Coastal zones are active reactors of continental material including that transported by rivers via a series of microbiota-mediated reactions. Nevertheless, current knowledge of the ecology and functioning of the microbiota in coastal areas affected by large riverine inputs remains insufficient on a global scale. Here, an investigation on sediment microbial composition, including taxonomy and metabolic network, as well as their relationship with major benthic reaction substrates, namely carbon, nitrogen, sulphur and phosphorus, was conducted in the continental shelf affected by the spread of the Changjiang River plume. Surface sediment samples(48 samples)were collected during March 2018, obtaining a mean Operational Taxonomic Units(OTUs) number of 3 ***, Acidobacteria and Actinobacteria were abundant phyla in the studied sediments. Bray-Curtis distance analysis classified the 48 samples into 4 clusters(MG1 to MG4) at the phylum-level. MG1 and MG2 are found near the river mouth, receiving substantial land-derived particles from the Changjiang River ***-attached microbes may be settled in these regions and influenced the observed sediment microbial diversity and biomass, e.g., increased Crenarchaeota relative abundance. The relative enrichment of these two groups in heterotrophic microbes further suggests a reliance of benthic microbiota on substrates with terrestrial origin, particularly specialized on processing sulphur-rich substrates. Regions MG3 and MG4 are located in the outer margin of the area affected by the Changjiang River plume, mainly fed by settling pelagic particles from phytoplankton. Compared to MG1 and MG2, a significant increase in the abundance of Thaumarcheota(phylumlevel) and Nitrosopumilus(genus-level) was found in MG3, suggesting nitrogen-related transformations as the key reactions to sustain microbial metabolism in this region. Coupled with the identified variations in the taxonomic composition, significant differenc

关键词： benthic microbiota biogeography benthic substrate Changjiang River plume East China Sea Yellow Sea

An Efficient Real-Time Fault-Tolerant Scheduling Algorithm Based on Multiprocessor Systems

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Wuhan University Journal of Natural Sciences 2007年第1期12卷 113-116页

作者： YANG Fumin LUO wei PANG liping College of Computer Science and Technology HuazhongUniversity of Science and Technology Wuhan 430074 Hubei China

In the context of real-time fault-tolerant scheduling in multiprocessor systems, Primary-backup scheme plays an important role. A backup copy is always preferred to be executed as passive backup copy whenever possible because it can take the advantages of backup copy de-allocation technique and overloading technique to improve schedulability. In this paper, we propose a novel efficient fault-tolerant ratemonotonic best-fit algorithm efficient fault-tolerant rate-monotonic best-fit （ERMBF） based on multiprocessors systems to enhance the schedulability. Unlike existing scheduling algorithms that start scheduling tasks with only one processor. ERMBF pre-allocates a certain amount of processors before starting scheduling tasks, which enlarge the searching spaces for tasks. Besides, when a new processor is allocated, we reassign the task copies that have already been assigned to the existing processors in order to find a superior tasks assignment configuration. These two strategies are all aiming at making as many backup copies as possible to be executed as passive status. As a result, ERMBF can use fewer processors to schedule a set of tasks without losing real-time and fault-tolerant capabilities of the system. Simulation results reveal that ERMBF significantly improves the schedulability over existing, comparable algorithms in literature.

关键词： real-time periodic tasks fault-tolerance primary/backup copy multiprocessor systems

Numerical simulation of water-slag elbow erosion-inhibiting by regulating the slag injection position with a novel preceding rotating sheet structure

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Particuology 2024年第7期90卷 323-339页

作者： Fopeng Wen Liuyun Xu Yixiang Chen Zhaofu Deng Shen Zhang Wenming Song Yuge Li liping wei School of Chemical Engineering Northwest UniversityXi’an710069China School of Chemistry and Chemical Engineering Yan'an UniversityYan'an716000China Machinery Industry Shanghai Lanya Petrochemical Equipment Inspection Institute Co. Ltd.Shanghai201518China The Research Center of Chemical Engineering Applying Technology for Resource of Shaanxi Xi’an710069China

The elbow erosion seriously jeopardizes the safe and stable operation of water–slag discharge pipeline of the coal gasification *** work simulated water–slag elbow characteristics with various slag injection positions by simulating five simplified and representative erosion categories,including A-type horizontal-vertical elbow with an upstream flow,B-type horizontal-vertical elbow with a downstream flow,C-type vertical-horizontal elbow with an upstream flow,D-type vertical-horizontal elbow with a downstream flow and E-type horizontal-horizontal *** with the C/D-type elbow,where particles were injected uniformly,the A-type elbow and E-type elbow were found to increase erosion rate,while the B-type elbow decreases erosion *** interesting discovery is that the elbow erosion rate is relatively low for small particles when particles are injected from the middle and bottom positions of the inlet section of the *** on the observation,a novel preceding rotating sheet structure was developed to regulate the particle injection *** shows an excellent anti-erosion performance by reducing the maximum erosion rate of particles with diameters of 50,100,and 200μm by 23%,35%,and 43%,respectively.

关键词： Erosion Slag-water Uneven particles Elbow pipe Erosion inhibition Preceding rotating sheet structure

Candidate Mycobacterium tuberculosis genes targeted by human microRNAs

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Protein & Cell 2010年第5期1卷 419-421页

作者： weiRui Guo Jiong-Tang Li Xiao Pan liping wei Jane Y.Wu Institute of Biophysics Chinese Academy of Sciences15 Datun RoadBeijing 100101China Center for Bioinformatics National Laboratory of Protein Engineering and Plant Genetic EngineeringCollege of Life SciencesPeking UniversityBeijing 100871China Department of Neurology Center for Genetic MedicineLurie Comprehensive Cancer CenterNorthwestern University Feinberg School of Medicine303 E.SuperiorChicagoIL 60611USA Graduate University of Chinese Academy of Sciences 19A Yuquan RoadBeijing 100039China

Tuberculosis(TB)remains a major health issue,causing approximately three million deaths every year(Pelicic et al.,1998).Identified by Robert Koch in 1882,Mycobacterium tuberculosis(***),the causative agent for tuberculosis,remains one of the most enigmatic *** interactions between *** and its environment have been extensively ***,our knowledge about potential ***-host interaction at the RNA level is still very *** we present our preliminary finding that suggests possible interactions of human miRNAs with *** transcripts and speculate possible roles of human miRNAs in regulating *** interactions.

关键词： tuberculosis al. targeted

MosaicBase:A Knowledgebase of Postzygotic Mosaic Variants in Noncancer Disease-related and Healthy Human Individuals

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Genomics, Proteomics & Bioinformatics 2020年第2期18卷 140-149页

作者： Xiaoxu Yang Changhong Yang Xianing Zheng Luoxing Xiong Yutian Tao Meng Wang Adam Yongxin Ye Qixi Wu Yanmei Dou Junyu Luo liping wei August Yue Huang Center for Bioinformatics State Key Laboratory of Protein and Plant Gene ResearchSchool of Life SciencesPeking UniversityBeijing 100871China Department of Bioinformatics Chongqing Medical UniversityChongqing 400016China College of Life Sciences Beijing Normal UniversityBeijing 100875China National Institute of Biological Sciences Beijing 102206China Peking-Tsinghua Center for Life Sciences(CLS) Academy for Advanced Interdisciplinary StudiesPeking UniversityBeijing 100871China Chinese Academy of Medical Sciences and Peking Union Medical College Beijing 100730China School of Life Sciences Peking UniversityBeijing 100871China

Mosaic variants resulting from postzygotic mutations are prevalent in the human genome and play important roles in human ***,except for cancer-related variants,there is no collection of postzygotic mosaic variants in noncancer disease-related and healthy ***,we present MosaicBase,a comprehensive database that includes 6698 mosaic variants related to 266 noncancer diseases and 27,991 mosaic variants identified in 422 healthy *** and phenotypic information of each variant was manually extracted and curated from 383 *** supports the query of variants with Online Mendelian Inheritance in Man(OMIM)entries,genomic coordinates,gene symbols,or Entrez *** also provide an integrated genome browser for users to easily access mosaic variants and their related annotations for any genomic *** analyzing the variants collected in MosaicBase,we find that mosaic variants that directly contribute to disease phenotype show features distinct from those of variants in individuals with mild or no phenotypes,in terms of their genomic distribution,mutation signatures,and fraction of mutant *** will not only assist clinicians in genetic counseling and diagnosis but also provide a useful resource to understand the genomic baseline of postzygotic mutations in the general human *** is publicly available at http://***/or http://49.***.21.8:8000.

关键词： Postzygotic Mosaicism Noncancer Mutation MosaicBase

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西藏不同种源光核桃仁脂肪酸组成分析

食品科学 2016年第22期37卷 107-111页

作者：王伟魏丽萍西藏农牧学院资源与环境学院西藏林芝860000

采用溶剂回流法及气相色谱法,分析全西藏范围内9个种源的光核桃仁出油率、油脂种类及相对含量特征。结果表明,9个种源的光核桃仁出油率差异显著,均值为44.96%;光核桃油中不饱和脂肪酸相对含量极高,均值为90.901%,主要由油酸和亚油酸组成... 详细信息

采用溶剂回流法及气相色谱法,分析全西藏范围内9个种源的光核桃仁出油率、油脂种类及相对含量特征。结果表明,9个种源的光核桃仁出油率差异显著,均值为44.96%;光核桃油中不饱和脂肪酸相对含量极高,均值为90.901%,主要由油酸和亚油酸组成,油酸相对含量的变化范围为45.280%-71.360%,最高值为芒康县的光核桃;亚油酸相对含量的变化范围为18.010%-44.340%,最高值为亚东县光核桃;饱和脂肪酸相对含量均值为9.099%,主要成分为棕榈酸和硬脂酸,棕榈酸相对含量的变化范围为5.829%-7.354%,最高值为亚东县光核桃;硬脂酸相对含量的变化范围为1.600%-3.034%,最高值为察隅县光核桃。基于11种脂肪酸相对含量特征的聚类分析表明,米林县、左贡县、波密县、八宿县光核桃仁油脂相对含量特征相近,芒康县则与其他种源光核桃油脂特征差异较大。

关键词：西藏光核桃仁出油率脂肪酸组成