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Efficient Helicopter-Satellite Communication Scheme Based on Check-Hybrid LDPC Coding

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Tsinghua Science and Technology 2018年第3期23卷 323-332页

作者： ping Wang Liuguo Yin Jianhua lu Department of Electronic Engineering Tsinghua University Beijing 100084 China EDA Laboratory Research Institute of Tsinghua Universityin Shenzhen Shenzhen 518057 China. School of Information Science andTechnology Tsinghua University Beijing 100084 China EDA Laboratory Research Institute ofTsinghua University in Shenzhen Shenzhen 518057 China Department of Electronic Engineering Tsinghua University Beijing 100084 China

When implementing helicopter-satellite communications, periodical interruption of the received signal is a challenging problem because the communication antenna is intermittently blocked by the rotating blades of the helicopter. The helicopter-satellite channel model and the Forward Error Control（FEC） coding countermeasure are presented in this paper. On the basis of this model, Check-Hybrid（CH） Low-Density Parity-Check（LDPC）codes are designed to mitigate the periodical blockage over the helicopter-satellite channels. The CH-LDPC code is derived by replacing part of single parity-check code constraints in a Quasi-Cyclic LDPC（QC-LDPC） code by using more powerful linear block code constraints. In particular, a method of optimizing the CH-LDPC code ensemble by searching the best matching component code among a variety of linear block codes using extrinsic information transfer charts is proposed. Simulation results show that, the CH-LDPC coding scheme designed for the helicopter-satellite channels in this paper achieves more than 25% bandwidth efficiency improvement, compared with the FEC scheme that uses QC-LDPC codes.

关键词： helicopter-satellite communications check-hybrid Low-Density Parity-Check(LDPC) codes Extrinsic Information Transfer(EXIT) iterative decoding

Enhanced Fatigue Property of Welded S355J2W Steel by Forming a Gradient Nanostructured Surface Layer

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Acta Metallurgica Sinica(English Letters) 2020年第9期33卷 1252-1258页

作者： lu An Yan-Tao Sun Shan-ping lu Zhen-Bo Wang Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China

Welded joints are usually characterized by microstructural and compositional inhomogeneities, which may significantly degrade their fatigue properties and result in unpredictable failures. The present work demonstrates a novel and simple method to effectively optimize the microstructure in the surface layer and promote the fatigue properties of welded specimens. By a recently developed approach—surface mechanical rolling treatment(SMRT), a gradient nanostructured surface layer is formed on welded S355 J2 W steel specimens. The mean grain size is refined to nanometer scale, and the hardness is significantly enhanced in the SMRT surface layer. Independent of the initially inhomogeneous microstructure and hardness distributions, the microstructure and hardness distributions in the surface layers are comparable on different zones of a welded specimen after SMRT with the same procedure. Consequently, fatigue property of the SMRT specimens is significantly enhanced relative to that of the as-welded specimens within the high cycle fatigue regime.

关键词： Gradient nanostructured Surface mechanical rolling treatment S355J2W steel Welded Fatigue

Application of Nanopore Sequencing Technology in the Clinical Diagnosis of Infectious Diseases

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Biomedical and Environmental Sciences 2022年第5期35卷 381-392页

作者： ZHANG lu lu ZHANG Chi PENG Jun ping NHC Key Laboratory of Systems Biology of Pathogens Institute of Pathogen BiologyChinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100176China Key Laboratory of Respiratory Disease Pathogenomics Chinese Academy of Medical SciencesBeijing 100176China

Infectious diseases are an enormous public health burden and a growing threat to human health *** or classic recurrent pathogens,or pathogens with resistant traits,challenge our ability to diagnose and control infectious *** sequencing technology has the potential to enhance our ability to diagnose,interrogate,and track infectious diseases due to the unrestricted read length and system *** review focuses on the application of nanopore sequencing technology in the clinical diagnosis of infectious diseases and includes the following:(i)a brief introduction to nanopore sequencing technology and Oxford Nanopore Technologies(ONT)sequencing platforms;(ii)strategies for nanopore-based sequencing technologies;and(iii)applications of nanopore sequencing technology in monitoring emerging pathogenic microorganisms,molecular detection of clinically relevant drug-resistance genes,and characterization of disease-related microbial ***,we discuss the current challenges,potential opportunities,and future outlook for applying nanopore sequencing technology in the diagnosis of infectious diseases.

关键词： Nanopore sequencing Infectious diseases Pathogen Oxford Nanopore Technologies

Boundedness of Multilinear Caldern–Zygmund Singular Operators on Morrey–Herz Spaces with Variable Exponents

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Acta Mathematica Sinica,English Series 2014年第7期30卷 1180-1194页

作者： Yan lu Yue ping ZHU School of Xinglin Nantong University School of Science Nantong University

In this paper, we introduce Morrey-Herz spaces MKq.p（·）α（·）,λ with variable exponents α（·） and p（·）, and prove the boundedness of multilinear Calderdn-Zygmund singular operators on the product of these... 详细信息

关键词： Morrey-Herz spaces variable exponents multilinear Calder6n-Zygmund singular operators

Confined nanospace pyrolysis: A versatile strategy to create hollow structured porous carbons

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Nano Research 2021年第9期14卷 3159-3173页

作者： Rui-ping Zhang Wen-Cui Li Guang-ping Hao An-Hui lu State Key Laboratory of Fine Chemicals School of Chemical EngineeringDalian University of TechnologyDalian 116024China

Confined nanospace pyrolysis(CNP)has attracted increasing attention as a general strategy to prepare task-specific hollow structured porous carbons(HSPCs)in the past *** unique advantages of the CNP strategy include its outstanding ability in control of the monodispersity,porosity and internal cavity of *** a consequence,the obtained HSPCs perform exceptionally well in applications where a high dispersibility and tailored cavity are particularly required,such as drug delivery,energy storage,catalysis and so *** this review,the fundamentals of the CNP strategy and its advances in structural alternation is first summarized,then typical applications are discussed by exemplifying specific synthesis *** addition,this review offers insights into future developments for advanced task-specific hollow structured porous materials prepared by the CNP strategy.

关键词： confined nanospace pyrolysis hollow structures carbon materials core-shell structures dispersibility

Activity of Stress-related Antioxidative Enzymes in the Invasive Plant Crofton Weed(Eupatorium adenophorum)

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Journal of Integrative Plant Biology 2007年第11期49卷 1555-1564页

作者： ping lu Wei-Guo Sang Ke-ping Ma Key Laboratory of Vegetation Ecology and Environment Change Institute of Botany the Chinese Academy of Sciences Beijing 100093 China Resources and Environmental Sciences College Northeast Agrfcultural University Harbin 150030 China

Crofton weed is an invasive weed in southwestern China. The activities of several antioxidative enzymes involved in plant protection against oxidative stress were assayed to determine physiological aspects of the crofton weed that might render the plant vulnerable to environmental stress. Stresses imposed on crofton weed were heat （progressively increasing temperatures： 25 ℃, 30 ℃, 35 ℃, 38℃ and 42 ℃ at 24 h intervals）, cold （progressively decreasing temperatures： 25 ℃, 20 ℃, 15℃, 10 ℃ and 5℃ at 24h intervals）, and drought （without watering up to 4days）. The three stresses induced oxidative damage as evidenced by an increase in lipid peroxidation. The effect varied with the stress imposed and the length of exposure. The activity of superoxide dismutase （SOD） increased in response to all stresses but was not significantly different from the controls （P 〈 0.05） when exposed to cold stress. Catalase （CAT） activity decreased in response to heat and drought stress but increased when exposed to cold conditions. Guaiacol peroxidase （POD） and glutathione reductase （GR） activities increased in response to cold and drought but decreased in response to heat stress. The activity of ascorbata peroxidase （APX） responded differently to all three stresses. Monodehydroascorbate reductase （MDHAR） activity decreased in response to heat and drought, and slightly increased in response to the cold stress but was not significantly different from the controls （P 〈 0.05）. The activity of dehydroascorbata reductase （DHAR） increased in response to all three stresses. Taken together, the co-ordinate increase of the oxygen-detoxifying enzymes might be more effective to protect crofton weed from the accumulation of oxygen radicals at low temperatures rather than at high temperatures.

关键词： antioxidative enzymes crofton weed invasive plant stress.

Differential Responses of the Activities of Antioxidant Enzymes to Thermal Stresses between Two Invasive Eupatorium Species in China

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Journal of Integrative Plant Biology 2008年第4期50卷 393-401页

作者： ping lu Wei-Guo Sang Ke-ping Ma Key Laboratory of Vegetation and Environment Change Institute of Botany the Chinese Academy of Sciences Beijing 100093 China Resources and Environmental Sciences College Northeast Agricuitural University Harbin 150030 China

The effect of thermal stress on the antioxidant system was investigated in two invasive plants, Eupatorium adenophorum Spreng. and E. odoratum L. The former is sensitive to high temperature, whereas the latter is sensitive to low temperature. Our aim was to explore the relationship between the response of antioxidant enzymes and temperature in the two invasive weeds with different distribution patterns in China. Plants were transferred from glasshouse to growth chambers at a constant 25 ℃for I week to acclimatize to the environment. For the heat treatments, temperature was increased stepwise to 30, 35, 38 and finally to 42 ℃. For the cold treatments, temperature was decreased stepwise to 20, 15, 10 and finally to 5 ℃. Plants were kept in the growth chambers for 24 h at each temperature step. In E. adenophorum, the coordinated increase of the activities of antioxidant enzymes was effective in protecting the plant from the accumulation of active oxygen species （AOS） at low temperature, but the activities of catalase （CAT）, guaiacol peroxidase （POD）, ascorbate peroxidase （APX）, glutathione reductase （GR）, and monodehydroascorbate reductase （MDAR） were not accompanied by the increase of superoxide dismutase （SOD） during the heat treatments. As a result, the level of lipid peroxidation in E. adenophorum was higher under heat stress than under cold stress. In E. odoratum, however, the lesser degree of membrane damage, as indicated by low monodehydroascorbate content, and the coordinated increase of the oxygen. Datoxifying enzymes were observed in heat-treated plants, but the antioxidant enzymes were unable to operate in cold stress. This indicates that the plants have a higher capacity for scavenging oxygen radicals in heat stress than in cold stress. The different responses of antioxidant enzymes may be one of the possible mechanisms of the differences in temperature sensitivities of the two plant species.

关键词： antioxidant enzyme system cold stress Eupatorium adenophorum Eupatorium odoratum heat stress invasive plants.

Self-assembled all-oxides three-phase vertically aligned nanocomposite thin film with multifunctionality

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Nano Research 2024年第9期17卷 8226-8232页

作者： Jijie Huang Yuan Fang ping lu Juanjuan lu Haiyan Wang School of Materials Shenzhen Campus of Sun Yat-sen UniversityShenzhen 518107China School of Materials Engineering Purdue UniversityWest LafayetteIN 47907USA Sandia National Laboratories AlbuquerqueNew Mexico 87185USA School of Electrical and Computer Engineering Purdue UniversityWest LafayetteIN 47907USA

Multi-phase vertically aligned nanocomposite(MP-VAN)thin films represent a promising avenue for achieving complex multifunctionality,exploring novel interfacial phenomena,and enabling complex metamaterial designs and *** this study,a novel self-assembled all-oxides three-phase VAN system was conceptualized and fabricated utilizing pulsed laser deposition(PLD)with a single composite *** microstructural analysis reveals the presence of three distinct phases:LiNbO_(3),CeO_(2-x),and LiNbCe_(1-x)O_(y)within the MP-VAN ***,ferroelectric,dielectric,optical anisotropy,and magnetic properties were systematically investigated to showcase the multifunctionality inherent in these *** work presents a pioneering approach to designing and realizing MP-VAN systems,and opens up opportunities for tailoring the complex three-dimensional(3D)physical properties and property coupling of VAN films towards diverse device applications.

关键词： thin film three-phase vertically aligned nanocomposite multifunctionality ferroelectricity optical anisotropy

Semi-solid Thixoforming Simulation of Al-Cu-Mn-Ti Alloy Parts via AnyCasting

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Journal of Materials Science & Technology 2007年第3期23卷 359-362页

作者： ping WANG Jianzhong CUI Guimin lu Key Laboratory of Ministry of Education for Electromagnetic Processing of Materials Northeastern University Shenyang 110004 China

The software AnyCasting was used to simulate the thixotropic die-casting process of semi-solid Al-Cu-Mn-Ti alloy slurry to form the parts of a particular shape, especially on how the in-gate size of die and injection speed affect the process. The results showed that the die cavity can be filled well with the semi-solid slurry in form of laminar flow under conditions that the temperature of the semi-solid slurry is 640℃ and that of die 200-240℃, thickness of in-gate is 11 mm and, more important, the injection speed should be changed from 0.1 to 1.0 m/s when 60% of die cavity has been filled. The simulation result is highly proved in conformity to the actual die-casting specimens in accordance to the filling process as simulated. Moreover, the hardness of the specimens is up to 116.6 HV after the treatment of solid solution plus underaging, i.e. 45.7% higher than that in conventional ones.

关键词： Al-Cu-Mn-Ti alloy Seml-solid die casting Laminar flow Hardness