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Apache IoTDB中的多模态数据编码压缩

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软件学报 2024年第3期35卷 1173-1193页

作者：贺文迪夏天睿宋韶旭黄向东王建民清华大学软件学院北京100084 大数据系统软件国家工程研究中心(清华大学) 北京100084 北京信息科学与技术国家研究中心(清华大学) 北京100084

时间序列数据在工业制造、气象、船舶、电力、车辆、金融等领域都有着广泛的应用,促进了时间序列数据库管理系统的蓬勃发展.面对愈加庞大的数据规模和多样的数据模态,高效的数据存储和管理方式十分关键,而数据的编码压缩愈发成为一个具... 详细信息

时间序列数据在工业制造、气象、船舶、电力、车辆、金融等领域都有着广泛的应用,促进了时间序列数据库管理系统的蓬勃发展.面对愈加庞大的数据规模和多样的数据模态,高效的数据存储和管理方式十分关键,而数据的编码压缩愈发成为一个具有重要意义和价值的问题.现有的编码方法和相关系统未能充分考虑不同模态的数据特点,或者未把一些时序数据的处理方法应用于数据编码问题中.全面阐述了ApacheIoTDB时序数据库系统中的多模态数据编码压缩方法及其系统实现,特别是面向工业物联网等应用场景.该编码方法较为全面地考虑包括时间戳数据、数值数据、布尔值数据、频域数据、文本数据等多个不同模态的数据,充分挖掘和利用各自模态数据的特点,特别是包括时间戳模态中时间戳序列间隔近似的特点等,进行有针对性的编码方案设计.同时,将实际应用场景中可能出现的数据质量问题因素纳入编码算法的考量中.在多个数据集上的编码算法层面和系统层面的实验评估和分析,验证了该编码压缩方法及其系统实现的效果.

关键词：数据编码时间序列数据数据库工业物联网多模态

Luminosity Limit of Super-Eddington Accretion onto Black Holes

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Chinese Physics Letters 1999年第6期16卷 467-468页

作者： wang jian-min Department of Astronomy Beijing Normal UniversityBeijing 100875 Chinese Academy of Sciences-Peking University Joint Beijing Astrophysical Center Beijing 100871

The luminosity limit is derived for the super-Eddington accretion by obtaining the self-similar *** maximum luminosity is about 4.0×10^(37) erg/s(M/M_(⊙))or so(significantly less than the Eddington luminosity)due to... 详细信息

关键词： accretion solution luminosity

利用ATR-FTIR研究脂质纳米粒的鼻黏液渗透性

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光谱学与光谱分析 2024年第4期44卷 1052-1060页

作者：王健敏李雪梅马士超李志勇唐华东马凤森浙江工业大学前沿交叉科学研究院浙江杭州310014 浙江工业大学化学工程学院浙江德清313216

鼻黏液是影响疫苗和药物经鼻吸收的首要屏障。由于干扰因素复杂多变,在体评价黏液渗透性较难实施,多采用体外评价。现有的药物鼻黏液渗透性检测方法如细胞模型法、多粒子示踪技术等,存在细胞培养周期长、操作繁琐、成本高、可获得信息... 详细信息

鼻黏液是影响疫苗和药物经鼻吸收的首要屏障。由于干扰因素复杂多变,在体评价黏液渗透性较难实施,多采用体外评价。现有的药物鼻黏液渗透性检测方法如细胞模型法、多粒子示踪技术等,存在细胞培养周期长、操作繁琐、成本高、可获得信息少且需要进行荧光标记等不足,对鼻黏膜制剂的体外评价具有很大的局限性,因此迫切需要建立一种快速、简便、灵敏的鼻黏膜制剂黏液渗透性评价方法。基于衰减全反射-傅里叶红外光谱(ATR-FTIR)对药物结构以及粘蛋白二级结构变化的敏感性,利用其对不同性质(粒径与电荷)脂质体的鼻黏液渗透性进行研究,通过FTIR图谱分析不同脂质纳米粒与黏液中粘蛋白的相互作用,建立了鼻黏膜制剂黏液渗透性的体外评价方法。方法学研究表明,对于聚乙二醇10000(PEG10000)、壳聚糖、海藻酸钠脂质体,该方法线性关系分别为Y=2.3866X+2.154、Y=1.8703X+0.2789、Y=1.13014X+0.0609,线性相关系数分别为0.9958、0.9945、0.9909,精密度RSD值分别为0.62%、0.73%、0.95%;重复性试验中RSD值分别为0.83%、0.97%、0.88%,说明该方法线性关系良好、精密度高、重复性好,可用于体外评价药物制剂在黏液中的渗透性。研究结果表明,利用ATR-FTIR在不同时间内扫描样品可得到不同脂质体制剂样品的强度增加的吸收带。对于不同粒径PEG脂质体而言,粒径越小其黏液渗透性越强;对于不同电荷脂质体而言,壳聚糖脂质体黏液渗透性最弱,海藻酸钠次之,PEG脂质体黏液渗透性最强。进一步研究表明,不同电荷脂质体黏液渗透性的差异源于其与粘蛋白相互作用,该结论可通过分析粘蛋白酰胺Ⅰ带所包含的各二级结构信息得到。综上,基于ATR-FTIR所建立的体外评价方法灵敏简便,可作为多种不同制剂的鼻黏液渗透性的快速测定,经改进后还可用于药物制剂在其他黏液中的渗透性评价,应用前景广阔。

关键词：脂质纳米粒 ATR-FTIR光谱渗透鼻黏液

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多信道无线通信网络动态数据完整性存储仿真

计算机仿真 2024年第7期41卷 451-455页

作者：王芳王建民邵芬红燕京理工学院信息科学与技术学院河北廊坊065201 华北理工大学电气工程学院河北唐山063000

在多信道环境下传输数据,易受无线通信网络连接不稳定性影响,且存在多个节点竞争同一资源的情况,导致数据冲突,影响数据存储的完整性。为此,提出一种多信道无线通信网络动态数据完整性存储方法。通过计算节点发送与接收的能耗,利用层次... 详细信息

在多信道环境下传输数据,易受无线通信网络连接不稳定性影响,且存在多个节点竞争同一资源的情况,导致数据冲突,影响数据存储的完整性。为此,提出一种多信道无线通信网络动态数据完整性存储方法。通过计算节点发送与接收的能耗,利用层次聚类算法,结合密度对网络监测区域内全部节点分簇处理,获取感知数据集合,采用最小二乘法采集动态数据,利用优化的谱哈希算法将高维网络动态数据映射为哈希码,利用基于柯西分布的哈希映射,得到概率密度函数,根据映射值间距,实现多信道无线通信网络动态数据完整性存储。通过仿真表明,所提方法的丢包率取值一直处于2%以下,吞吐率逐渐接近于98%,资源占用率最高仅为14.6%,可以获取满意的网络动态数据完整性存储结果。

关键词：多信道无线通信网络动态数据完整性存储优化谱哈希算法

Characteristics of Chang 2~1 Low PermeabilitySandstone Reservoir in Shunning Oil Field

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Journal of China University of mining and Technology 2006年第2期16卷 223-227页

作者： wang jian-min YU Liu-ying Department ofl Resource and Engineering Xi＇an Shiyou University Xi＇an Shaanxi 710065 China Department of Oil Field Incorporated Company of PetroChina Beijing 100000 China

Characteristics of Chang 21 low permeability sandstone reservoir of Shunning oil field are analyzed and evaluated based on the data of well logging and experiment. The result shows that 1) the Chang 21 low permeability reservoir belongs to the classification of middle-to-fine sized feldspar sandstone, with its components being low in ma- turity, deposited in distributary rivers in the front of the delta; 2) the reservoir is obviously dominated by a low or a very low permeability with a linear variation tendency different from that of the ultra-low permeability reservoir; 3) the spa- tial variation in lithology and physical properties of the reservoir are controlled by the sedimentary facies zones, and 4) the physical property of the reservoir is significantly influenced by clastic constituents and their structure, and the con- stituent of cement materials and their content. The result also shows that the diagenesis action of the reservoir is quite strong in which dissolution greatly modified the reservoir In addition, the inter-granular dissolved pores are the mainly developed ones and the micro-structure is dominated by the combination of middle-to-large sized pores with fine-to-coarse throats. Finally, the radius of the throats is in good exponential correlation with permeability and the seepage capacity comes from those large sized throats.

关键词： Chang 2^1 reservoir low permeability: reservoir characteristic evaluation

Hidden Tree Structure is a Key to the Emergence of Scaling in the World Wide Web

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Chinese Physics Letters 2011年第1期28卷 218-221页

作者： ZHENG Bo-Jin wang jian-min CHEN Gui-Sheng jianG jian SHEN Xian-Jun School of Software Tsinghua University Beijing 100084 College of Computer Science South-Central University for Nationalities Wuhan 430074 Institute of Chinese Electronic Engineering Beijing 100840 Institute of Command and Technology of Equipment Beijing 101416 Department of Computer Science Central-China Normal University Wuhan 430072

Preferential attachment is the most popular explanation for the emergence of scaling behavior in the World Wide Web, but this explanation has been challenged by the global information hypothesis, the existence of linear preference and the emergence of new big internet companies in the real world. We notice that most websites have an obvious feature that their pages are organized as a tree （namely hidden tree） and hence propose a new model that introduces a hidden tree structure into the Erd6s^R~nyi model by adding a new rule： when one node connects to another, it should also connect to all nodes in the path between these two nodes in the hidden tree. The experimental results show that the degree distribution of the generated graphs would obey power law distributions and have variable high clustering coefficients and variable small average lengths of shortest paths. The proposed model provides an alternative explanation to the emergence of scaling in the World Wide Web without the above-mentioned difficulties, and also explains the ＂preferential attachment＂ phenomenon.

关键词： Statistical physics and nonlinear systems

Large post-liquefaction deformation of sand:Mechanisms and modeling considering water absorption in shearing and seismic wave conditions

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Underground Space 2024年第5期18卷 3-64页

作者： jian-min Zhang Rui wang Department of Hydraulic Engineering State Key Laboratory of Hydroscience and EngineeringTsinghua UniversityBeijing 100084China

Large deformation of sand due to soil liquefaction is a major cause for seismic *** this study,the mechanisms and modeling of large post-liquefaction deformation of sand considering the significant influence of water absorption in shearing and seismic wave *** of case histories from past earthquakes and review of existing studies highlight the importance of the two *** on the micro and macro scale mechanisms for post-liquefaction shear deformation,the mechanism for water absorption in shearing after initial liquefaction is *** is aided by novel designed constant water-absorption-rate shear *** absorption in shearing can be classified into three types,including partial water absorption,complete water absorption,and compulsory water *** the influence of water absorption in shearing,even a strongly dilative sand under naturally drained conditions could experience instability and large shear *** mechanism for amplification of post-liquefaction deformation under surface wave load is also explained via element tests and theoretical *** shows that surface wave–shear wave coupling can induce asymmetrical force and resistance in sand,resulting in asymmetrical accumulation of deformation,which is amplified by liquefaction.A constitutive model,referred to as CycLiq,is formulated to capture the large deformation of sand considering water absorption in shearing and seismic wave conditions,along with its numerical implementation *** model is comprehensively calibrated based on various types of element tests and validated against centrifuge shaking table tests in the liquefaction experiments and analysis projects(LEAP).The model,along with various numerical analysis methods,is adopted in the successful simulation of water absorption in shearing and Rayleigh wave-shear wave coupling induced large liquefaction ***,the model is applied to high-performance simulation fo

关键词： Liquefaction Sand Large deformation Water absorption in shearing Surface wave Rayleigh wave-shear wave coupling

利用颗粒物激光雷达水平扫描污染源分布-实例分析

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环境科学导刊 2024年第4期43卷 27-29页

作者：刘浪王剑敏梅红兵彭剑平云南省环境监测中心站云南昆明650034

利用激光雷达对丽江市区出现的一次颗粒物轻度污染过程进行观测,反演数据得到颗粒物消光系数和退偏比,对颗粒物在水平方向上的分布特征进行分析,确定污染源相关信息。结果表明,监测点东面1 km附近农田秸秆燃烧和东南面1.7 km处云南XX物... 详细信息

利用激光雷达对丽江市区出现的一次颗粒物轻度污染过程进行观测,反演数据得到颗粒物消光系数和退偏比,对颗粒物在水平方向上的分布特征进行分析,确定污染源相关信息。结果表明,监测点东面1 km附近农田秸秆燃烧和东南面1.7 km处云南XX物流园颗粒物排放两个污染源对本次污染贡献较大。通过激光雷达水平扫描溯源定位污染源,能及时为环境管理部门精准治理提供技术支撑,从而实现源头管理。

关键词：激光雷达消光系数退偏比颗粒物污染过程

Expression of a novel dipeptidyl peptidase 8(DPP8)transcript variant,DPP8-v3,in human testis

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Asian Journal of Andrology 2005年第3期7卷 245-255,页

作者： Hui Zhu Zuo-min Zhou Li Lu min Xu Hui wang jian-min Li Jia-Hao Sha Key Laboratory of Reproductive Medicine Department of Histology and Embryology Nanjing Medical UniversityNanjing 210029 China

Aim： To investigate the role of a novel dipeptidyl peptidase 8 transcript variant （DPP8-v3） gene in testis development and/or spermatogenesis. Methods： A human testis cDNA microarray was hybridized with mRNA of human adult and fetal testes. Differentially expressed clones were sequenced and characterized and their expression was analyzed by real-time reverse transcription polymerase chain reaction （RT-PCR） and Southern-blot analysis. Results： A new transcript variant of the human dipeptidyl peptidase （DPP8）, exhibiting a 5-fold higher expression level in human adult than that in fetal testes, was cloned and was named DPP8 variant 3 （DPP8-v3）. The full-length sequence of DPP8-v3 was 3,030 bp, encoding a protein of 898 amino acids. Conclusion： DPPS-v3 is a novel human DPP8 transcript variant highly expressed in the adult testis. Similar to DPPIV, DPP8-v3 may play a key role in the immunoregulation of testes and accordingly may influence spermatogenesis and male fertility. （Asian J Androl 2005 Sep; 7： 245-255）

关键词： DPP8 dipeptidyl peptidase IV (DPPIV) DPP8-v3 immunoregulation spermatogenesis testis