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机载图像无损/近无损压缩方案及其FPGA实现

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北京航空航天大学学报 2006年第12期32卷 1443-1446,1467页

作者：刘波姜宏旭练有品逯进元北京航空航天大学电子信息工程学院北京100083 北京航空航天大学计算机学院北京100083 后勤工程学院后勤信息工程系重庆400042 中国网通集团公司河北分公司石家庄050000

根据机载图像压缩和传输的特点,在改进JPEG-LS算法基础上,设计了一种有效的图像无损/近无损压缩方案.该方案由去相关处理、熵编码及压缩位率控制三部分组成.去相关处理部分解决了JPEG-LS预测模型本身的误码扩散问题,熵编码部分使用快速... 详细信息

根据机载图像压缩和传输的特点,在改进JPEG-LS算法基础上,设计了一种有效的图像无损/近无损压缩方案.该方案由去相关处理、熵编码及压缩位率控制三部分组成.去相关处理部分解决了JPEG-LS预测模型本身的误码扩散问题,熵编码部分使用快速有效的Golomb熵编码器完成对预测误差的编码,同时解决了机载应用中数据传输率恒定条件下压缩码率的控制问题.对压缩算法现场可编程门阵列(FPGA)设计中的一些关键问题也给出了有效的解决途径,从而形成了一套完整、可行的机载图像压缩解决方案.最后通过FPGA实现和验证了压缩方案及逻辑设计的正确性和可行性.

关键词：图像编码图像压缩实时系统现场可编程门阵列(FPGA)

High-efficiency prediction method for helicopter global/ground noise based on near-field acoustic holography

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Chinese Journal of Aeronautics 2024年第7期37卷 271-284页

作者： Mengxue SHAO Yang lu Xice XU Jiaxin lu National Key Laboratory of Helicopter Aeromechanics Nanjing University of Aeronautics and AstronauticsNanjing 210016China

Noise reduction program design is an effective approach that relies on efficient noise prediction for reducing ground noise during *** existing noise prediction methods have the limitations of being computationally expensive or only applicable to *** this paper,a High-Efficiency Prediction Method(HEPM)for helicopter global/ground noise based on near-field acoustic holography is *** HEPM can predict the global noise based on acoustic modal analysis and has the advantages of high prediction accuracy and low time *** process is given as follows:firstly,the rotor noise on the holographic surface in the specified flight is obtained by simulations or ***,the global noise model,which maps time-domain noise to acoustic modes,is established based on near-field acoustic holography and Fourier acoustic analysis ***,combined with acoustic modal amplitude,the model established enables efficiently predicting the global/ground noise in the corresponding flight *** verify the accuracy of the prediction method,a simulation study is conducted in hovering and forward flight states using a model helicopter with a 2-meter rotor and Rotor Body Interaction(ROBIN)*** comparison of HEPM with numerical results shows that the average prediction errors of the global and ground noise are less than 0.3 dB and 0.2 dB,*** a region containing 100000 observers,the computation time of the HEPM is only one-fifth of that of the acoustic hemisphere method,demonstrating the rapidity of the proposed method.

关键词： Helicopter Rotor noise prediction Noise abatement procedure design Acoustic modal analysis Near-field acoustic holography

Optical grade (Gd_(0.95-x)lu_(x)Eu_(0.05))_(3)Al_(5)O_(12) ceramics with near-zero optical loss: Effects of lu^(3+) doping on structural feature, microstructure evolution, and far-red luminescence

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Journal of Advanced Ceramics 2024年第1期13卷 113-123页

作者： Zhigang Sun Ji-Guang Li Huiyu Qian Yoshio Sakka Tohru SSuzuki Bin lu School of Materials Science and Chemical Engineering Ningbo UniversityNingbo 315211China Research Center for Electronic and Optical Materials National Institute for Materials ScienceIbaraki 305-0044Japan Key Laboratory of Photoelectric Detection Materials and Devices of Zhejiang Province Ningbo 315211China

A chemical co-precipitation strategy was employed to synthesize a series of(Gd_(0.95−x)lu_(x)Eu_(0.05))_(3)Al_(5)O_(12)(x=0.1−0.95)powder phosphors,followed by vacuum sintering to achieve transparent garnet ceramic *** density functional theory indicated lu_(3)Al_(5)O_(12) was formed in priority compared with Gd_(3)Al_(5)O_(12) during solid-phase *** high-temperature sintering,the lu^(3+)substitution for Gd^(3+)suppressed point mass diffusion leading to a smaller grain *** in-line transmittances of bulk specimens with x=0.1,0.3,0.5,0.7,and 0.95 nm were~83.5%,80.1%,68.8%,73.7%,and 82.2%at 710 nm(Eu^(3+)emission center),respectively,among which the sample of x=0.1 exhibited the optical grade with near-zero optical loss in agreement with the defect-free single crystal(~100%of the theoretical transmittance).The resulting particle and ceramic materials both presented characteristic Eu^(3+)emission arising from 5D0→7FJ(J=1−4)transition,where the dominant far-red emission at~710 nm arising from ^(5)D_(0)→^(7)F_(4) transition overlapped with the absorption of phytochrome(PFR).The photoluminescence excitation and photoluminescence intensities of(Gd_(0.95−x)lu_(x)Eu_(0.05))_(3)Al_(5)O_(12) powders and ceramics generally increased at a higher Gd^(3+)/lu^(3+)***^(3+)dopants delayed the fluorescence lifetime while the bulk samples had shorter lifetime compared to the particle *** transparent(Gd_(0.85)lu_(0.1)Eu_(0.05))3Al_(5)O_(12) ceramic phosphor exhibited good thermal stability with a high thermal quenching temperature above 533 *** designed ceramic phosphor-converted light-emitting diode had a saturation injection current of 435 mA and a current-dependent color rendering *** importantly,our report marked the developmental stage of transparent ceramic materials towards zero optical loss.

关键词： transparent ceramics garnet phosphors light-emitting diode(LED) optical properties Gibbs free energy

Collective Molecular Machines: Multidimensionality and Reconfigurability

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Nano-Micro Letters 2024年第8期16卷 309-340页

作者： Bin Wang Yuan lu Department of Chemical Engineering Tsinghua UniversityBeijing 100084People’s Republic of China Key Laboratory of Industrial Biocatalysis Ministry of EducationTsinghua UniversityBeijing 100084People’s Republic of China

Molecular machines are key to cellular activity where they are involved in converting chemical and light energy into efficient mechanical *** the last 60 years,designing molecular structures capable of generating unidirectional mechanical motion at the nanoscale has been the topic of intense *** progress has been made,attributed to advances in various fields such as supramolecular chemistry,biology and nanotechnology,and ***,individual molecular machines are only capable of producing nanometer work and generally have only a single *** order to address these problems,collective behaviors realized by integrating several or more of these individual mechanical units in space and time have become a new *** this review,we comprehensively discuss recent developments in the collective behaviors of molecular *** particular,collective behavior is divided into two *** is the appropriate integration of molecular machines to efficiently amplify molecular motions and deformations to construct novel functional *** other is the construction of swarming modes at the supramolecular level to perform nanoscale or microscale *** discuss design strategies for both modes and focus on the modulation of features and ***,in order to address existing challenges,the idea of transferring experience gained in the field of micro/nano robotics is presented,offering prospects for future developments in the collective behavior of molecular machines.

关键词： Molecular machines Collective control Collective behaviors DNA Biomolecular motors

Soil inorganic amendments produce safe rice by reducing the transfer of Cd and increasing key amino acids in brown rice

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Journal of Environmental Sciences 2024年第2期136卷 121-132页

作者： Fanyi Kong Shenggao lu Zhejiang Provincial Key Laboratory of Agricultural Resources and Environment Key Laboratory of Environmental Remediation and Ecosystem HealthMinistry of EducationCollege of Environmental and Resource SciencesZhejiang UniversityHangzhou 310058China

The digestibility of cadmium(Cd)in brown rice is directly related to amino acid metabolism in rice and human *** our field study,three kinds of alkaline calcium-rich soil inorganic amendments(SIAs)at three dosages were applied to produce safe rice and improve the quality of rice in Cd-contaminated *** the increased application of SIA,Cd content in iron plaque on rice root significantly increased,the transfer of Cd from rice root to grain significantly decreased,and then Cd content in brown rice decreased *** vitro digestibility of Cd in brown rice was estimated by a physiologically based extraction *** showed that more than 70%of Cd in brown rice could be digested by simulated gastrointestinal *** on the total and digestible Cd contents in brown rice to evaluate the health risk,the application of 2.25 ton SIA/ha could produce safe rice in acidic slightly Cd-contaminated paddy *** amino acids(AAs)in brown rice were determined by high-performance liquid *** contents of 5 key AAs(KAAs)that actively respond to environmental changes increased significantly with the increased application of *** structural equation model indicated that KAAs could be affected by the Cd translocation capacity from rice root to grain,and consequently altered the ratio of indigestible Cd in brown *** formation of indigestible KAAs-Cd complexes by combining KAAs(phenylalanine,leucine,histidine,glutamine,and asparagine)with Cd in brown rice could be considered a potential mechanism for reducing the digestibility of Cd.

关键词： Cadmium digestibility Soil inorganic amendments Safe rice Amino acid Priming effect Health risk

每日唤醒对ICU慢性阻塞性肺疾病行机械通气患者的影响

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中国医药科学 2019年第9期9卷 194-196页

作者：陆锦源广东省佛山市南海区第四人民医院广东佛山528211

目的分析每日唤醒对ICU慢性阻塞性肺疾病行机械通气患者产生的影响。方法此次纳入研究100例ICU慢性阻塞性肺疾病行机械通气患者均为2014年11月～2017年11月收治,参加此次研究患者均给予芬太尼与丙泊酚进行镇痛和镇静,在此基础上以随机... 详细信息

目的分析每日唤醒对ICU慢性阻塞性肺疾病行机械通气患者产生的影响。方法此次纳入研究100例ICU慢性阻塞性肺疾病行机械通气患者均为2014年11月～2017年11月收治,参加此次研究患者均给予芬太尼与丙泊酚进行镇痛和镇静,在此基础上以随机分组的形式将其分为两组,对照组50例患者不予以唤醒,实验组50例患者予以每日唤醒,对其效果进行分析。结果 (1)实验组患者心率、呼吸频率、动脉血氧、动脉二氧化碳分压、平均动脉压均优于对照组患者,差异有统计学意义(P 0.05)。(2)实验组患者停药后完全清醒时间与机械通气时间均较对照组患者短,组间对比数据差异有统计学意义(P <0.05)。(3)实验组患者停药后不良反应发生率(14.0%)较对照组患者停药后不良反应发生率(34.0%)低,差异有统计学意义(P <0.05)。结论每日唤醒在ICU慢性阻塞性肺疾病行机械通气患者中有着重要的意义,可改善患者呼吸循环指标,缩短停药后完全清醒时间,降低停药后不良反应的发生,加速患者的康复,值得在临床中推广应用。

关键词：每日唤醒 ICU 慢性阻塞性肺疾病机械通气

On the Monge–Kantorovich Mass Transfer Problem in Higher Dimensions

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Acta Mathematica Sinica,English Series 2024年第8期40卷 1989-2004页

作者： Xiao Jun lu School of Mathematics Southeast UniversityNanjing 210096P.R.China

This paper mainly investigates the approximation of a global maximizer of the Monge–Kantorovich mass transfer problem in higher dimensions through the approach of nonlinear partial differential equations with Dirichlet *** an approximation mechanism,the primal maximization problem can be transformed into a sequence of minimization *** applying the systematic canonical duality theory,one is able to derive a sequence of analytic solutions for the minimization *** the final analysis,the convergence of the sequence to an analytical global maximizer of the primal Monge–Kantorovich problem will be demonstrated.

关键词： Monge-Kantorovich mass transfer singular variational problem canonical duality theory

A solution method for decomposing vector fields in Hamilton energy

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Chinese Physics B 2024年第9期33卷 645-653页

作者： Xin Zhao Ming Yi Zhou-Chao Wei Yuan Zhu lu-lu lu School of Mathematics and Physics China University of GeosciencesWuhan 430074China

Hamilton energy,which reflects the energy variation of systems,is one of the crucial instruments used to analyze the characteristics of dynamical *** we propose a method to deduce Hamilton energy based on the existing *** derivation process consists of three steps:step 1,decomposing the vector field;step 2,solving the Hamilton energy function;and step 3,verifying *** order to easily choose an appropriate decomposition method,we propose a classification criterion based on the form of system state variables,i.e.,type-I vector fields that can be directly decomposed and type-II vector fields decomposed via exterior ***,exterior differentiation is used to represent the curl of low-high dimension vector fields in the process of ***,we exemplify the Hamilton energy function of six classical systems and analyze the relationship between Hamilton energy and dynamic *** solution provides a new approach for deducing the Hamilton energy function,especially in high-dimensional systems.

关键词： Hamilton energy dynamical systems vector field exterior differentiation

Progress of vegetation modelling and future research prospects

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Science China Earth Sciences 2024年第9期67卷 2718-2738页

作者： Siqi LI Xu ZHANG Zhengyao lu Jian NI Jianhua lu State Key Laboratory of Tibetan Plateau Earth System Resources and Environment(TPESRE)Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China College of Resources and Environment University of Chinese Academy of SciencesBeijing 100049China British Antarctic Survey Cambridge CB30ETUnited Kingdom Department of Physical Geography and Ecosystem Science Lund UniversityLund 22362Sweden College of Life Sciences Zhejiang Normal UniversityJinhua 321004China School of Atmospheric Sciences Sun Yat-sen University and Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai)Zhuhai 519082China

Terrestrial vegetation is a crucial component of the Earth system,and its changes not only represent one of the most distinct aspects of climate change but also exert significant feedback within the climate system by exchanging energy,moisture,and carbon *** quantitatively and mechanistically study climate-vegetation feedback,numerical vegetation models have been developed on the theory of ecophysiological constraints on plant functional *** models eventually can simulate vegetation distribution and succession across different spatial and temporal scales,and associated terrestrial carbon cycle processes by categorizing vegetation into biomes according different plant functional types and their associated environmental *** we review the developing history of vegetation models and provide recent advances and future *** 21st century,static vegetation models,as developed statistical models,can only simulate equilibrated characteristics of vegetation *** last several decades,Dynamic Global Vegetation Models(DGVMs)have been developed to simulate instantaneous responses of vegetation to climate change and associated dynamics,and can be coupled with Earth system models to investigate interactions among atmosphere,ocean,and *** are also widely applied to investigate the dynamics accounting for changes in the geographic distribution patterns of land surface vegetation at different spatial and temporal scales and to assess the impacts of terrestrial carbon and water fluxes and land use *** suggest that future vegetation modeling could integrate with machine learning,and explore vegetation transient response and feedback as well as impacts of process hierarchies and human activities on climate and ecosystem.

关键词： Vegetation models DGVMs Ecosystems Plant functional types Plant functional traits

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