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CONTROL CHAOS IN TRANSITION SYSTEM USING SAMPLED-DATA FEEDBACK 被引量:1
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作者 陆君安 谢进 +1 位作者 吕金虎 陈士华 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2003年第11期1309-1315,共7页
The method for controlling chaotic transition system was investigated using sampled- data . The output of chaotic transition system was sampled at a given sampling rate , then the sampled output was used by a feedback... The method for controlling chaotic transition system was investigated using sampled- data . The output of chaotic transition system was sampled at a given sampling rate , then the sampled output was used by a feedbacks subsystem to construct a control signal for controlling chaotic transition system to the origin . Numerical simulations are presented to show the effectiveness and feasibility of the developed controller. 展开更多
关键词 sampled-data feedback transition system CONTROL
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Transition Logic Regression Method to Identify Interactions in Binary Longitudinal Data 被引量:1
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作者 Parvin Sarbakhsh Yadollah Mehrabi +2 位作者 Jeanine J. Houwing-Duistermaat Farid Zayeri Maryam Sadat Daneshpour 《Open Journal of Statistics》 2016年第3期469-481,共13页
Logic regression is an adaptive regression method which searches for Boolean (logic) combinations of binary variables that best explain the variability in the outcome, and thus, it reveals interaction effects which ar... Logic regression is an adaptive regression method which searches for Boolean (logic) combinations of binary variables that best explain the variability in the outcome, and thus, it reveals interaction effects which are associated with the response. In this study, we extended logic regression to longitudinal data with binary response and proposed “Transition Logic Regression Method” to find interactions related to response. In this method, interaction effects over time were found by Annealing Algorithm with AIC (Akaike Information Criterion) as the score function of the model. Also, first and second orders Markov dependence were allowed to capture the correlation among successive observations of the same individual in longitudinal binary response. Performance of the method was evaluated with simulation study in various conditions. Proposed method was used to find interactions of SNPs and other risk factors related to low HDL over time in data of 329 participants of longitudinal TLGS study. 展开更多
关键词 Logic Regression Longitudinal data transition Model Interaction TLGS Study Low HDL SNP
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Unconventional phase transition of phase-change-memory materials for optical data storage 被引量:2
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作者 Nian-Ke Chen Xian-Bin Li 《Chinese Physics B》 SCIE EI CAS CSCD 2019年第10期73-82,共10页
Recent years, optically controlled phase-change memory draws intensive attention owing to some advanced applications including integrated all-optical nonvolatile memory, in-memory computing, and neuromorphic computing... Recent years, optically controlled phase-change memory draws intensive attention owing to some advanced applications including integrated all-optical nonvolatile memory, in-memory computing, and neuromorphic computing. The light-induced phase transition is the key for this technology. Traditional understanding on the role of light is the heating effect. Generally, the RESET operation of phase-change memory is believed to be a melt-quenching-amorphization process. However, some recent experimental and theoretical investigations have revealed that ultrafast laser can manipulate the structures of phase-change materials by non-thermal effects and induces unconventional phase transitions including solid-to-solid amorphization and order-to-order phase transitions. Compared with the conventional thermal amorphization,these transitions have potential superiors such as faster speed, better endurance, and low power consumption. This article summarizes some recent progress of experimental observations and theoretical analyses on these unconventional phase transitions. The discussions mainly focus on the physical mechanism at atomic scale to provide guidance to control the phase transitions for optical storage. Outlook on some possible applications of the non-thermal phase transition is also presented to develop new types of devices. 展开更多
关键词 light-matter interaction PHASE-CHANGE MEMORY NON-THERMAL phase transition optical data storage
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T_(BB) DATA-REVEALED FEATURES OF ASIAN-AUSTRALIAN MONSOON SEASONAL TRANSITION AND ASIAN SUMMER MONSOOM ESTABLISHMENT 被引量:3
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作者 何金海 朱乾根 《Journal of Tropical Meteorology》 SCIE 1997年第1期18-26,共9页
Based on TBB data from Meteorological Institute Research of Japan, study is carried out of the features of seasonal transition of Asian-Australian monsoons and Asian summer monsoon establishment,indicating that the tr... Based on TBB data from Meteorological Institute Research of Japan, study is carried out of the features of seasonal transition of Asian-Australian monsoons and Asian summer monsoon establishment,indicating that the transition begins as early as in April, followed by abrupt change in May-June; the Asian summer monsoon situation is fully established in June. The winter convective center in Sumatra moved steadily northwestward across the "land bridge" of the maritime continent and the Indo-China Peninsula as time goes from winter to summer, thus giving rise to the change in large scale circulations that is responsible for the summer monsoon establishment over SE Asia and India; the South China Sea to the western Pacific summer monsoon onset bears a close relation to the active convection in the Indo China Peninsula and steady eastward retreat of the subtropical TBB high-value band,corresponding to the western Pacific subtropical high. 展开更多
关键词 T_(BB) data Asian-Australian monsoon reston seasonal transition features of summer monsoon establishment
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Data processing in pulse transit time measurement
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作者 Jingmeng Zhang Ye Li 《生命科学仪器》 2008年第8期18-21,共4页
PuLse transit time(FIT)is used as a noninvasive and cull-less parameter to estimate blood pressure.In this paper,we develop an algorithm to obtain FTT rapidly,which is appropriate for micro-processor and could achieve... PuLse transit time(FIT)is used as a noninvasive and cull-less parameter to estimate blood pressure.In this paper,we develop an algorithm to obtain FTT rapidly,which is appropriate for micro-processor and could achieve good accuracy in PTT,even in noisy measurements.The algorithm is based on finite impulse response(FIR)filter to reduce the noise and an adaptive threshold to detect the significant points of ECG and PPG.Evaluation of this method is based on the signals from our PTr-based blood pressure devices.It is shown that the method works well for PPT calculation. 展开更多
关键词 脉冲技术 测量方法 数据处理 转换时间
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Public Transit Performance Evaluation Using Data Envelopment Analysis and Possibilities of Enhancement
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作者 Sunil Sujakhu Wenquan Li 《Journal of Transportation Technologies》 2020年第2期89-109,共21页
This study evaluates the operational performance of all routes of Sajha Bus Yatayat operating inside Kathmandu valley using Data Envelopment Analysis (DEA) in terms of efficiency and effectiveness score. This approach... This study evaluates the operational performance of all routes of Sajha Bus Yatayat operating inside Kathmandu valley using Data Envelopment Analysis (DEA) in terms of efficiency and effectiveness score. This approach allows us to access the relative performance of transit system in absence of historical data and research to compare with. To explore the possibility of enhancing the performance, scenarios were created for relatively underperforming routes and long route problem by changing the most important input variable and output variables accordingly with regression model where it was relevant. Partial Least Squares (PLS) regression was used to determine the most influential input variables to the output variables. DEA was conducted to access the performance of all routes under these scenarios. Underperforming routes except the longest route under the first set of scenarios, emerge to be better performing efficiently without considerable negative deviation in effectiveness. The result of second set of scenarios for long route problem suggests that the longest route’s performance can be enhanced significantly upon proper route alignment. Scenarios development and evaluation can help lead transit companies to explore the strategies to facilitate operational performance enhancement. 展开更多
关键词 PUBLIC transit System data Envelopment Analysis Performance Evalua-tion Partial Least SQUARES Regression
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Data processing in pulse transit time measurement
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作者 张静萌 《生命科学仪器》 2008年第10期28-32,共5页
Pulse transit time (PTT) is used as a noninvasive and cuff-less parameter to estimate blood pressure. In this paper, we develop an algorithm to obtain PTT rapidly, which is appropriate for micro-processor and could ac... Pulse transit time (PTT) is used as a noninvasive and cuff-less parameter to estimate blood pressure. In this paper, we develop an algorithm to obtain PTT rapidly, which is appropriate for micro-processor and could achieve good accuracy in PTT, even in noisy measurements. The algorithm is based on finite impulse response (FIR) filter to reduce the noise and an adaptive threshold to detect the significant points of ECG and PPG. Evaluation of this method is based on the signals from our PTT-based blood pressure devices. It is shown that the method works well for PPT calculation. 展开更多
关键词 脉冲中转时间 数据处理 测量方法 脉冲技术
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SH^(+)离子18个Λ-S态和35个Ω态光谱性质的理论研究
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作者 邢伟 李胜周 +3 位作者 张昉 孙金锋 李文涛 朱遵略 《物理学报》 北大核心 2026年第5期81-97,共17页
基于精确处理核-价电子关联、标量相对论效应、自旋-轨道耦合效应及完全基组极限等多种物理效应,本文使用icMRCI+Q方法构建了SH^(+)离子18个Λ-S态及相应的35个Ω态的势能曲线.利用全电子icMRCI/cc-pCV5Z+SOC理论框架,计算得到7个Ω态[... 基于精确处理核-价电子关联、标量相对论效应、自旋-轨道耦合效应及完全基组极限等多种物理效应,本文使用icMRCI+Q方法构建了SH^(+)离子18个Λ-S态及相应的35个Ω态的势能曲线.利用全电子icMRCI/cc-pCV5Z+SOC理论框架,计算得到7个Ω态[包括X^(3)Σ_(0+)^(−),X^(3)Σ_(1)^(−),(1)2^(第一势阱)(υ'=0—8),(2)0+(υ'=0—5),(2)2^(第一势阱)(υ'=0—2),(2)1^(第一势阱)(υ'=0—2)和(3)0+(υ'=0—2)]间12对系统的跃迁偶极距曲线.基于上述势能曲线和跃迁偶极距曲线,通过求解核运动的Schrödinger方程并结合相应公式,确定了各态的光谱数据和Ω态间的跃迁数据,所得结果与实验值吻合很好.此外阐明了12对辐射跃迁的光谱特性、揭示了激发Ω态的辐射寿命和辐射宽度变化规律、讨论了转动量子数(J')对(2)2^(第一势阱)(υ'=0—2,+),(2)1^(第一势阱)(υ'=0—2,+)和(3)0+(υ'=0—2,+)态的辐射寿命的影响.本文数据集可在https://www.doi.org/10.57760/sciencedb.j00213.00233中访问获取. 展开更多
关键词 标量相对论 自旋-轨道耦合 势能曲线 跃迁偶极矩 光谱数据
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轨道列车车载数据分类分级研究
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作者 杨慕晨 崔佳南 +2 位作者 崔玉龙 刘汉 吴冬寒 《制造业自动化》 2026年第1期95-104,共10页
随着轨道交通智能化进程加速,轨道列车车载数据的分类分级成为实现数据资产化与安全管控的核心挑战。以动车组列车车载数据为研究对象,该研究介绍了数据分类分级的方法,并针对车载数据规模大、异构性强、实时性高及多源关联性显著的特征... 随着轨道交通智能化进程加速,轨道列车车载数据的分类分级成为实现数据资产化与安全管控的核心挑战。以动车组列车车载数据为研究对象,该研究介绍了数据分类分级的方法,并针对车载数据规模大、异构性强、实时性高及多源关联性显著的特征,结合实践系统分析了车载数据分类分级的关键技术,阐述明确规范标准、构建分类分级模板、分类分级评估分析及加强后续管理等开展车载数据分类分级的关键环节,并介绍引入大模型赋能车载数据分类分级的方法及应用情况,论证了其在车载数据分类分级工作中规模应用的可行性,为进一步提升轨道交通领域的数据高效利用和安全管理水平提供支持。 展开更多
关键词 数据分类 数据分级 轨道列车车载数据
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城市轨道交通客流大数据可视化方法研究
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作者 蒋政 吕希奎 刘新华 《城市轨道交通研究》 北大核心 2026年第3期174-179,共6页
[目的]既有的静态图表分析法无法直观地展现客流数据随时间变化的时变性及随空间属性变化的空间不对称性,无法从海量的交通客流大数据中有效提取出站点属性及乘客出行特性规律,有必要寻求城市轨道交通客流大数据的可视化方法。[方法]以... [目的]既有的静态图表分析法无法直观地展现客流数据随时间变化的时变性及随空间属性变化的空间不对称性,无法从海量的交通客流大数据中有效提取出站点属性及乘客出行特性规律,有必要寻求城市轨道交通客流大数据的可视化方法。[方法]以上海轨道交通线网2015年4月份客流数据为研究对象,首先对客流数据进行预处理,清除了城市轨道交通出行以外的噪声数据。其次从不均衡客流、线路客流、站点客流3个方面,分析了城市轨道交通客流时间特性分布的可视化方法。最后从线路和站点的客流空间分布、断面客流分布及OD(起讫点)客流空间分布3个方面,分析了城市轨道交通客流空间特性分布的可视化方法。[结果及结论]采用不同类型的图表(柱状图、类树状图、蛛网图、动态渲染图等)进行可视化多维直观展示,可以更好地理解城市轨道交通客流时空分布特征。通过对历史和现状数据中潜在的信息进行分析与价值挖掘,可以实现对未来客流复杂动态的精准预测。 展开更多
关键词 城市轨道交通 客流大数据 数据可视化
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城市轨道交通区间盾构隧道数字化设计系统
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作者 方黄磊 《铁道建筑》 北大核心 2026年第1期173-178,共6页
现有的隧道工程数字化技术多应用于参数化建模、方案集成展示等领域,缺乏针对隧道数字化设计的系统性研究。本文以城市轨道交通区间盾构隧道设计为背景,研发了一套以数据为核心的隧道数字化设计系统。通过梳理盾构隧道设计业务,剖析传... 现有的隧道工程数字化技术多应用于参数化建模、方案集成展示等领域,缺乏针对隧道数字化设计的系统性研究。本文以城市轨道交通区间盾构隧道设计为背景,研发了一套以数据为核心的隧道数字化设计系统。通过梳理盾构隧道设计业务,剖析传统设计方式存在的痛点,提出了专业间数据协同、工点项目数据管理、由数据驱动生成设计成果等业务数字化需求。基于这些需求开展了系统功能设计、系统架构设计、数据库及接口设计等工作,研发了多插件式、二三维联动的盾构隧道设计系统,并在实际工程项目中进行应用。结果表明:该系统能有效覆盖盾构隧道设计全业务流程,大幅降低设计人工耗时,设计信息可向施工、运维阶段快速传递。 展开更多
关键词 城市轨道交通 盾构隧道 数字化设计 数据协同 软件研发
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Fine Structure Calculations of Atomic Data for Ar XVI
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作者 A. I. Refaie 《Journal of Modern Physics》 2015年第11期1609-1630,共22页
Fine structure energy levels, wavelengths, log gf and allowed transition probabilities (E1) have been calculated for Lithium-like Ar XVI. The optimized electrostatic parameters by a least square approach, have been us... Fine structure energy levels, wavelengths, log gf and allowed transition probabilities (E1) have been calculated for Lithium-like Ar XVI. The optimized electrostatic parameters by a least square approach, have been used in the calculation to include the configuration interaction and relativistic effects. A total number of 69 Ar XVI levels having total angular momenta, 1/2 ≤ J ≤ 9/2 of even and odd parities, orbital angular momenta 2 ≤ l ≤ 4, with 546 E1 transitions for 6 ≤ n ≤ 10 are considered using the relativistic effect in the Breit-Pauli method, where n is the principal quantum number. A comparison is made with the available results in literature. 展开更多
关键词 ATOMIC data transitION Probabilities AR XVI
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Extreme ultraviolet and x-ray transition wavelengths in Rb XXIV
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作者 Indu Khatri Arun Goyal +2 位作者 Sunny Aggarwal A.K.Singh Man Mohan 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第10期115-126,共12页
Energy levels, radiative rates, oscillator strengths and line strengths are reported for transitions among the lowest 97 levels of the(1s22s22p6) 3s23p2, 3s23p3 d, 3s3p3, 3p4, 3s3p23 d, and 3s23d2 configurations of ... Energy levels, radiative rates, oscillator strengths and line strengths are reported for transitions among the lowest 97 levels of the(1s22s22p6) 3s23p2, 3s23p3 d, 3s3p3, 3p4, 3s3p23 d, and 3s23d2 configurations of Rb XXIV. A multiconfiguration Dirac-Fock(MCDF) method is adopted for the calculations. Radiative rates, oscillator strengths, and line strengths are provided for all electric dipole(E1), magnetic dipole(M1), electric quadrupole(E2), and magnetic quadrupole(M2)transitions from the ground level to all 97 levels, although calculations are performed for a much larger number of levels.To achieve the accuracy of the data, comparisons are provided with similar data obtained from the Flexible Atomic Code(FAC) and also with the available theoretical and experimental results. Our energy levels are found to be accurate to better than 1.2%. Wavelengths calculated are found to lie in EUV(extreme ultraviolet) and x-ray regions. Additionally, lifetimes for all 97 levels are obtained for the first time. 展开更多
关键词 atomic data energy levels transition probability
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Relativistic atomic data for W XLVⅡ
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作者 Sunny Aggarwal A.K.S.Jha +2 位作者 Indu Khatri Narendra Singh Man Mohan 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第5期305-312,共8页
Energy levels, radiative rates, and lifetimes are calculated for all levels of 3s23p, 3s23d, 3s3p2, 3s3d2, 3s3p3d, 3p23d, 3s3d2, 3p3d2, 3p3, and 3d3 configurations of Al-like tungsten ion (W XLVII). Multiconfigurati... Energy levels, radiative rates, and lifetimes are calculated for all levels of 3s23p, 3s23d, 3s3p2, 3s3d2, 3s3p3d, 3p23d, 3s3d2, 3p3d2, 3p3, and 3d3 configurations of Al-like tungsten ion (W XLVII). Multiconfigurational Dirac-Fock (MCDF) method is adopted for calculating energy levels and radiative rates. Oscillator strengths, radiative rates, and line strengths are reported for some E1 transitions from the ground level. Comparisons are made with the available data in the literature and good agreement has been found which confirms the reliability of our results. 展开更多
关键词 atomic data multiconfigurational Dirac-Fock method transition probability
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基于钆塞酸二钠增强MRI的LI-RADS 5类标准改良版对亚厘米肝细胞癌诊断效能的分析 被引量:1
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作者 邢飞 朱文静 +4 位作者 姜吉锋 陆健 张涛 马秦榕 邢伟 《临床放射学杂志》 北大核心 2025年第2期308-314,共7页
目的探讨基于钆塞酸二钠增强MRI(Gd-EOB-MRI)的肝脏影像报告和数据系统(LI-RADS)5类标准改良版对亚厘米肝细胞癌(scHCC)的诊断效能。方法选取2014年7月至2022年3月行Gd-EOB-MRI检查并检出<2.0 cm肝脏局灶性病灶的375例患者。由两名... 目的探讨基于钆塞酸二钠增强MRI(Gd-EOB-MRI)的肝脏影像报告和数据系统(LI-RADS)5类标准改良版对亚厘米肝细胞癌(scHCC)的诊断效能。方法选取2014年7月至2022年3月行Gd-EOB-MRI检查并检出<2.0 cm肝脏局灶性病灶的375例患者。由两名放射科医师依据LI-RADS v2018对病灶进行分析,采用卡方检验分析<1.0 cm(scHCC)与1.0~1.9 cm肝细胞癌(HCC)的主要和辅助征象的差异,采用Logistic回归分析筛选出与scHCC显著相关的辅助征象。采用受试者操作特征曲线(ROC)评价LI-RADS v2018标准及改良版LI-RADS(mLI-RADS,应用重要辅助征象调整<1.0 cm病灶的LR-5类标准)对HCC的诊断效能,采用DeLong检验比较不同曲线下面积(AUC)的差异。结果375例患者共452个病灶(<1.0 cm,n=173;1.0~1.9 cm,n=279),HCC病灶215个、非HCC恶性肿瘤病灶21个、良性病灶216个。与1.0~1.9 cm的HCC相比,scHCC门脉期(PVP)非周边廓清(WO)(35.4%vs.72.1%,P<0.001)、强化包膜(EC)(8.9%vs.30.1%,P<0.001)、T_(2)WI轻-中度高信号(63.3%vs.87.5%,P<0.001)及扩散加权成像(DWI)扩散受限(67.1%vs.83.8%,P=0.004)的显示率较低。移行期(TP)低信号是诊断scHCC唯一独立的辅助征象(OR=5.24,P<0.001)。调整<1.0 cm病灶的LR-5类标准后[<1.0 cm+非环状动脉期高强化(APHE)+WO(PVP或TP低信号)],35个LR-3结节(<1.0 cm+非环状APHE+TP低信号)、28个LR-4结节(<1.0 cm+非环状APHE+PVP低信号)上调至LR-5。以LR-5为诊断标准,mLI-RADS诊断HCC的敏感性(71.2%vs.45.6%,P<0.001)、准确性(82.1%vs.71.7%,P<0.001)显著高于LI-RADS v2018,而特异性相似(92.0%vs.95.4%,P=0.131),其AUC显著高于LI-RADS v2018(0.824 vs.0.705,P<0.001)。结论TP低信号是诊断scHCC重要的辅助征象,将WO扩展至PVP/TP评估并调整<1.0 cm病灶的LR-5类标准,mLI-RADS能够显著提高HCC(尤其scHCC)的诊断效能。 展开更多
关键词 钆塞酸二钠 肝脏影像报告与数据系统 肝细胞癌 移行期 亚厘米
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Design of Data Model for Urban Transport GIS
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作者 Wen Zeng Xiao-Jie Chang Jian-Jun Lv 《Journal of Geographic Information System》 2010年第2期106-112,共7页
Constructing the data model for public transportation by integrating the spatial and the non-spatial information, is the basis of reasonable plan and effective management of urban public transport. This paper presents... Constructing the data model for public transportation by integrating the spatial and the non-spatial information, is the basis of reasonable plan and effective management of urban public transport. This paper presents a transit data model based on geographic information systems (GIS) technology, which utilizes arc-node networks, and manages the foundational bus data with point, link, polygon and record features. In this model, a transport network is generated and maintained in a dynamic manner, and hence supports planning, construction, management, operation and optimization functions for transit facilities and routes, as well as day-to-day transactions. Public transportation GIS established on this model foundation will remarkably upgrade the construction level and the urban service ability. 展开更多
关键词 GEOGRAPHIC INFORMATION System (GIS) transit GIS transit ROUTE Network data MODE
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数据要素赋能、质态变迁与制造业新质生产力 被引量:10
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作者 宋炜 王杰 +1 位作者 周勇 董明放 《科技进步与对策》 北大核心 2025年第1期21-29,共9页
新发展格局下,制造业新质生产力不仅取决于数据要素赋能,而且受到开放型经济新体制中质态变迁的影响。利用2010—2022年中国制造业面板数据,探讨数据要素赋能与质态变迁对制造业新质生产力的影响。在区分数据要素赋能类型的基础上纳入... 新发展格局下,制造业新质生产力不仅取决于数据要素赋能,而且受到开放型经济新体制中质态变迁的影响。利用2010—2022年中国制造业面板数据,探讨数据要素赋能与质态变迁对制造业新质生产力的影响。在区分数据要素赋能类型的基础上纳入质态变迁,结果发现,数据要素偏向型赋能引致的质态变迁无法持续承接全球价值链中高端技术革命性突破,会阻碍制造业创新发展,因而对制造业新质生产力的促进作用不显著。数据要素增强型赋能引致的质态变迁能够大幅提升制造业生产系统的复杂性,以及制造业创新系统的前沿性,促进创新发展动力演化,对中国制造业新质生产力发挥显著正向作用。 展开更多
关键词 数据要素偏向型赋能 数据要素增强型赋能 质态变迁 制造业新质生产力
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智能轨道交通数据安全防护体系:挑战、技术与未来演进
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作者 陈磊 杨玉欣 公备 《都市快轨交通》 北大核心 2025年第5期8-14,共7页
为解决轨道交通数据规模急剧膨胀、数据价值不断提升导致的安全问题,对智能轨道交通数据的安全防护体系进行研究。首先梳理轨道交通数据具有的多源异构、高实时性及强敏感性的特征,并分析在数据传输、存储和处理过程中的主要安全风险点... 为解决轨道交通数据规模急剧膨胀、数据价值不断提升导致的安全问题,对智能轨道交通数据的安全防护体系进行研究。首先梳理轨道交通数据具有的多源异构、高实时性及强敏感性的特征,并分析在数据传输、存储和处理过程中的主要安全风险点;然后探讨针对网络攻击、数据泄露等威胁的联邦学习、轻量级加密、动态访问控制等前沿防护技术在资源受限环境下的应用现状、适用条件与性能表现;最后提出人工智能赋能的主动防御、跨系统协同治理等智能轨道交通数据安全未来的重点研究方向。研究结果表明:联邦学习可有效解决数据孤岛问题,在保证隐私前提下提升模型训练效率;轻量级加密算法在轨旁设备中展现出毫秒级响应优势,具有显著的应用潜力,是未来的发展趋势。研究成果可以为构建高效、可靠的智能轨道交通数据安全防护体系提供理论支撑和实践指导。 展开更多
关键词 轨道交通 数据安全 网络安全 隐私保护 加密技术
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Modeling of Imperfect Data in Medical Sciences by Markov Chain with Numerical Computation
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作者 Mahmoud Afshari Anoshirvan Ghaffaripour 《Advances in Bioscience and Biotechnology》 2014年第13期1003-1008,共6页
In this paper we consider sequences of observations that irregularly space at infrequent time in-tervals. We will discuss about one of the most important issues of stochastic processes, named Markov chains. We would r... In this paper we consider sequences of observations that irregularly space at infrequent time in-tervals. We will discuss about one of the most important issues of stochastic processes, named Markov chains. We would reconstruct the collected imperfect data as a Markov chain and obtain an algorithm for finding maximum likelihood estimate of transition matrix. This approach is known as EM algorithm, which includes main optimum advantages among other approaches, and consists of two phases: phase (maximization of target function). Continue the phase E and M to achieve the sequence convergence of matrix. Its limit is the optimal estimator. This algorithm, in contrast with other optimum algorithms which could be used for this purpose, is practicable in maximum likelihood estimate, and unlike to the methods which involve mathematical, is executable by computer. At the end we will survey the theoretical outcomes with numerical computation by using R software. 展开更多
关键词 MARKOV CHAIN Matrix transition Maximum LIKELIHOOD EM Algorithm MISSING data
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新质生产力视域下碳数据质量执法保障问题分析 被引量:2
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作者 潘晓滨 徐倩 《湖北师范大学学报(哲学社会科学版)》 2025年第5期1-9,共9页
新质生产力本身是绿色生产力,对推动低碳经济和社会转型至关重要。碳数据质量是全国碳排放管理及碳市场健康发展的重要基础。我国已构建以《碳排放权交易管理暂行条例》为核心的碳数据质量管理体系,尽管法律框架基本搭建,但实践中,《条... 新质生产力本身是绿色生产力,对推动低碳经济和社会转型至关重要。碳数据质量是全国碳排放管理及碳市场健康发展的重要基础。我国已构建以《碳排放权交易管理暂行条例》为核心的碳数据质量管理体系,尽管法律框架基本搭建,但实践中,《条例》颁行前后的碳数据质量执法案例仍暴露出法律责任不健全,执法程序不完备,大数据技术与数据质量保障融合度不深,激励支持手段缺失等问题。结合提升碳排放数据质量执法保障的现实需要,我们仍有必要从实体法层面完善法律责任制度供给,从程序法层面细化执法规则,从技术和财政金融保障性制度层面做好执法支撑。通过优化执法保障机制,可以确保碳数据的真实性和准确性,为低碳转型提供坚实的数据支持。 展开更多
关键词 新质生产力 碳数据质量 执法保障 低碳转型
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