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Vasoactive intestinal polypeptide (VIP) corrects chronic inflammatory response syndrome (CIRS) acquired following exposure to water-damaged buildings 被引量:1
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作者 Ritchie C. Shoemaker Dennis House James C. Ryan 《Health》 2013年第3期396-401,共6页
Exposure in water-damaged buildings (WDB) to airborne bioaerosols including metabolic products of toxigenic fungi, bacteria and actinomycetes;and inflammagens, can lead to a persistent innate immune inflammatory illne... Exposure in water-damaged buildings (WDB) to airborne bioaerosols including metabolic products of toxigenic fungi, bacteria and actinomycetes;and inflammagens, can lead to a persistent innate immune inflammatory illness. This illness, termed a chronic inflammatory response syndrome (CIRS-WDB), is systemic with symptoms acquired from multiple organ systems. Treatment of CIRS-WDB has progressed rapidly as a better understanding of the inflammatory pathophysiology has led to targeted, sequential therapies. The fundamental basis of uncontrolled innate immune responses, the humoral deficiency of regulatory neuropeptides melanocyte stimulating hormone (MSH) or vasoactive intestinal polypeptide (VIP), seen in over 98% of pa tients, has not consistently responded to any treatment modality. Use of replacement VIP has been attempted anecdotally;VIP replacement therapies show promise in short term studies but longer therapies have not been attempted. Here we report an open label trial of 20 patients with refractory CIRS-WDB illness who took replacement VIP in a nasal spray for at least 18 months with confirmation of durable efficacy and absence of significant side effects. These 20 patients were similar in symptoms and lab find- ings to three previously published cohorts in- volving 1829 patients and 169 controls. Dosage of VIP was titrated downwards from four to zero doses a day to determine minimum effective dose, and retitrated upwards for maximum improvement over time. The trial showed that VIP therapy safely 1) reduced refractory symptoms to equal controls;2) corrected inflammatory parameters C4a, TGF beta-1, VEGF, MMP9;3) corrected estradiol, testosterone and 25-OH Vitamin D;4) returned pulmonary artery systolic pressure (PASP) during exercise to normal;and 5) enhanced quality of life in 100% of trial patients. Subsequent identification of correction of T-regulatory cell levels supports the potential role of VIP in both innate and adaptive immune function. 展开更多
关键词 Vasoactive Intestinal POLYPEPTIDE (VIP) CHRONIC Inflammatory Response Syndrome (cirs) TGF Beta-1 C4a MSH T Regulatory Cells Water-Damaged BUILDINGS
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A time domain multiple-CFOs and CIRs estimation algorithm over wireless multimedia sensor networks
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作者 姜建 《High Technology Letters》 EI CAS 2009年第3期294-300,共7页
Channel parameters estimation in an orthogonal for the receiver station is a multi-dimensional (MD) frequency division multiple access (OFDMA) system optimization problem, because every user node has a separate lo... Channel parameters estimation in an orthogonal for the receiver station is a multi-dimensional (MD) frequency division multiple access (OFDMA) system optimization problem, because every user node has a separate local oscillator and every transmitter to receiver link has individual carrier frequency offset (CFO) and channel impulse response (CIR) parameters. In order to reduce the computational complexity for MD optimization, a time domain CFOs and CIRs estimation algorithm over the OFDMA based wireless multimedia sensor networks (WMSN) is proposed in this paper. In this algorithm, the receiver station can decouple the signal from every node by correlation based on specially designed training sequences, so that the MD optimization problem is simplified to an 1-D optimal problem. It is proved that the multiple CFOs can be identified from the correlation result using the phase shift of the consecutive training se- quences. Based on the CFOs estimation result, the CIRs can then he estimated according to the minimum mean square error (MMSE) criterion. The theoretic analysis and simulation results show that the proposed algorithm can effectively decouple the signal from different user nodes and the bit error rate (BER) per- formance curves are close to the ideal estimation when the user number is not large. 展开更多
关键词 wireless multimedia sensor networks (WMSN) orthogonal frequency division multiple access (OFDMA) multiple carrier frequency offsets (CFOs) multiple channel impulse responses cirs minimum mean square error (MMSE)
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均值—方差准则下考虑利率风险的DC型养老金计划
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作者 常浩 孙秀秀 李佳奥 《运筹与管理》 北大核心 2025年第3期141-148,共8页
假定金融市场包括一种无风险资产、多种股票和一种零息票债券,其中利率满足Cox-Ingersoll-Ross利率模型。基金管理人旨在寻找一种最优投资策略使投资收益最大化的同时最小化投资风险。首先,运用拉格朗日乘子法和拉格朗日对偶定理将原均... 假定金融市场包括一种无风险资产、多种股票和一种零息票债券,其中利率满足Cox-Ingersoll-Ross利率模型。基金管理人旨在寻找一种最优投资策略使投资收益最大化的同时最小化投资风险。首先,运用拉格朗日乘子法和拉格朗日对偶定理将原均值—方差模型转化为二次效用函数下的等价问题。然后,通过求解Hamilton-Jacobi-Bellman方程得到了预先承诺策略和有效前沿。最后,给出数值算例对所得结果进行了解释。 展开更多
关键词 CIR利率模型 DC型养老基金投资 均值—方差准则 有效策略 有效前沿
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一种网络智能信息Agent——CIRs的设计
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作者 蔡智 于琨 +1 位作者 王煦法 蔡庆生 《复旦学报(自然科学版)》 CAS CSCD 北大核心 2004年第5期830-833,共4页
Web上大量、分布、动态的信息,造成了用户在查询Web上的信息时产生"信息过载"和"信息迷向"现象.智能信息Agent是解决此问题的研究热点.设计并实现了一种以智能化、主动搜索为标志的互联网智能信息Agent—CIRs,从用... Web上大量、分布、动态的信息,造成了用户在查询Web上的信息时产生"信息过载"和"信息迷向"现象.智能信息Agent是解决此问题的研究热点.设计并实现了一种以智能化、主动搜索为标志的互联网智能信息Agent—CIRs,从用户日常的行为中自动学习出用户兴趣模型,从而为用户提供个性化Web信息服务. 展开更多
关键词 智能信息Agent CIR WEB信息 信息过载 用户兴趣模型 查询 搜索 服务 网络智能 动态
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Novel optimization techniques for underwater wireless optical communication links:using Monte Carlo simulation
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作者 Intesar Ramley Hamdah MAlzayed +2 位作者 Yas Al-Hadeethi Abeer ZBarasheed Mingguang Chen 《Defence Technology(防务技术)》 2025年第8期386-411,共26页
The Underwater Communication Link(UCL)is a crucial component of Underwater Wireless Optical Communication(UWOC)systems,requiring optimised design to mitigate the high power attenuation inherent in seawater.To ensure t... The Underwater Communication Link(UCL)is a crucial component of Underwater Wireless Optical Communication(UWOC)systems,requiring optimised design to mitigate the high power attenuation inherent in seawater.To ensure the reliability of an optimal UCL design,it is essential to account for the three primary scattering regimes:forward scattering(FSC),backward scattering(BSC),and isotropic scattering(ISC)in seawater channels.This study introduces a new photon-tracking model based on a discrete equation,facilitating Monte Carlo Simulation(MCS)to evaluate how different scattering regimes influence received photon distribution.Three distinct Scattering Regime Contribution Weight(SRCW)probability sets were employed,each representing different UCL operational configurations dominated by specific scattering regimes.The proposed modeling approach enables a comprehensive assessment of the temporal characteristics of received optical pulses,channel loss,and time spread-ultimately defining the optimal UCL design parameters.The key findings of this study include:(1)Enhancing the FSC regime dominance leads to a quasi-light waveguide effect over link spans and small Fields of View(FOV)<25°,significantly improving channel performance in Harbor seawater compared to Coastal seawater.(2)A well-designed UCL with a small FOV(<25°)can minimise channel loss and time spread,ensuring high capacity and efficient performance in both Coastal and Harbor seawaters.(3)When BSC and ISC contributions exceed FSC dominance,the received optical pulse undergoes significant temporal broadening,particularly for larger FOV angles(>25°)and extended link spans.(4)The developed novel MCS-based discrete equation provides a simple yet robust model for simulating photon propagation in both homogeneous and inhomogeneous underwater channels.These insights contribute to developing more efficient and reliable UCL designs with military standards by enhancing UWOC system performance over a longer linkspan for a given limited optical power across various underwater environments. 展开更多
关键词 Channel gain/loss Channel impulse response(CIR) Central limit theorem(CLT) Channel time spread Field of view(FOV) Monte Carlo simulation(MCS) Underwater wireless optical communication(UWOC)
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基于银行间同业拆放利率的长记忆随机利率模型研究 被引量:2
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作者 孙晓霞 王冰 《统计研究》 CSSCI 北大核心 2024年第2期149-160,共12页
研究表明利率序列具有长记忆性,故本文使用分数布朗运动代替经典CIR模型中的几何布朗运动,构建分数CIR模型,并通过欧拉离散对分数CIR过程进行路径模拟。由于分数布朗运动的非马尔可夫性和增量不独立,无法使用极大似然估计和马尔可夫链... 研究表明利率序列具有长记忆性,故本文使用分数布朗运动代替经典CIR模型中的几何布朗运动,构建分数CIR模型,并通过欧拉离散对分数CIR过程进行路径模拟。由于分数布朗运动的非马尔可夫性和增量不独立,无法使用极大似然估计和马尔可夫链蒙特卡洛方法对分数CIR模型进行参数估计,故本文引入间接推断估计法,并通过蒙特卡洛模拟证明该方法的可行性。本文使用间接推断估计法对我国银行间同业拆放利率数据进行实证分析及样本外预测,将经典CIR模型、分数O-U过程、分数CIR模型的拟合轨道与真实轨道进行分析对比,得出分数CIR模型更适用于描述具有长记忆性的利率序列。本文重点研究一种用于分数CIR模型的参数估计方法,未来将继续探究其他参数估计方法并对比这些方法的有效性和稳健性。 展开更多
关键词 长记忆性 分数布朗运动 分数CIR模型 间接推断估计
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Novel Sum-of-Sinusoids Simulation Channel Modeling for 6G Multiple-Input Multiple-Output Vehicle-to-Everything Communications
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作者 Hao Jiang Hongming Zhang Ting Liu 《China Communications》 SCIE CSCD 2024年第1期242-259,共18页
In this paper,a statistical cluster-based simulation channel model with a finite number of sinusoids is proposed for depicting the multiple-input multiple-output(MIMO)communications in vehicleto-everything(V2X)environ... In this paper,a statistical cluster-based simulation channel model with a finite number of sinusoids is proposed for depicting the multiple-input multiple-output(MIMO)communications in vehicleto-everything(V2X)environments.In the proposed sum-of-sinusoids(SoS)channel model,the waves that emerge from the transmitter undergo line-of-sight(LoS)and non-line-of-sight(NLoS)propagation to the receiver,which makes the model suitable for describing numerous V2X wireless communication scenarios for sixth-generation(6G).We derive expressions for the real and imaginary parts of the complex channel impulse response(CIR),which characterize the physical propagation characteristics of V2X wireless channels.The statistical properties of the real and imaginary parts of the complex CIRs,i.e.,autocorrelation functions(ACFs),Doppler power spectral densities(PSDs),cross-correlation functions(CCFs),and variances of ACFs and CCFs,are derived and discussed.Simulation results are generated and match those predicted by the underlying theory,demonstrating the accuracy of our derivation and analysis.The proposed framework and underlying theory arise as an efficient tool to investigate the statistical properties of 6G MIMO V2X communication systems. 展开更多
关键词 complex cirs LoS and NLoS propagation components MIMO V2X communication environments SoS simulation channel model statistical properties
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基于CIR模型的地铁客流弹性分析
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作者 徐玉萍 侯明超 《大连交通大学学报》 CAS 2024年第1期20-25,共6页
为量化地铁系统的弹性,从客流的角度提出基于Cox-Ingersoll-Ross(CIR)模型的客流弹性指标。以单个或多个车站为对象,通过CIR模型模拟其在短期内进站客流和换乘客流的波动行为,并依此量化客流弹性。此外,讨论多车站的客流弹性与其各组成... 为量化地铁系统的弹性,从客流的角度提出基于Cox-Ingersoll-Ross(CIR)模型的客流弹性指标。以单个或多个车站为对象,通过CIR模型模拟其在短期内进站客流和换乘客流的波动行为,并依此量化客流弹性。此外,讨论多车站的客流弹性与其各组成车站的内在关联。研究表明:客流弹性指标能够定量描述扰动后的客流恢复过程;中间车站的客流具有波动小、弹性高的特征;换乘车站的客流具有波动大、弹性低的特征;多车站的客流弹性与其中最大客流车站的弹性呈正相关,而多车站的客流弹性在其中小客流车站的弹性及客流量影响下呈现3种不同情况。 展开更多
关键词 轨道交通 CIR模型 客流弹性
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FCN-Attention:A deep learning UWB NLOS/LOS classification algorithm using fully convolution neural network with self-attention mechanism 被引量:3
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作者 Yu Pei Ruizhi Chen +2 位作者 Deren Li Xiongwu Xiao Xingyu Zheng 《Geo-Spatial Information Science》 CSCD 2024年第4期1162-1181,共20页
The Ultra-Wideband(UWB)Location-Based Service is receiving more and more attention due to its high ranging accuracy and good time resolution.However,the None-Line-of-Sight(NLOS)propagation may reduce the ranging accur... The Ultra-Wideband(UWB)Location-Based Service is receiving more and more attention due to its high ranging accuracy and good time resolution.However,the None-Line-of-Sight(NLOS)propagation may reduce the ranging accuracy for UWB localization system in indoor environment.So it is important to identify LOS and NLOS propagations before taking proper measures to improve the UWB localization accuracy.In this paper,a deep learning-based UWB NLOS/LOS classification algorithm called FCN-Attention is proposed.The proposed FCN-Attention algorithm utilizes a Fully Convolution Network(FCN)for improving feature extraction ability and a self-attention mechanism for enhancing feature description from the data to improve the classification accuracy.The proposed algorithm is evaluated using an open-source dataset,a local collected dataset and a mixed dataset created from these two datasets.The experiment result shows that the proposed FCN-Attention algorithm achieves classification accuracy of 88.24%on the open-source dataset,100%on the local collected dataset and 92.01%on the mixed dataset,which is better than the results from other evaluated NLOS/LOS classification algorithms in most scenarios in this paper. 展开更多
关键词 Ultra Wideband(UWB) None-line-of-sight(NLOS)identification channel impulse response(CIR) deep learning fully convolution network self-attention mechanism
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Solar energetic particles intensity variations associated with a tilted-dipole 3D corotating interaction region 被引量:1
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作者 YuJi Zhu Fang Shen +2 位作者 Xi Luo Yang Wang BoFeng Tang 《Earth and Planetary Physics》 EI CAS CSCD 2024年第5期797-810,共14页
The effect of a tilted-dipole three-dimensional corotating interaction region(CIR)on the transport and acceleration of solar energetic particles(SEPs)is studied.In this work,we discussed how the particle intensity lon... The effect of a tilted-dipole three-dimensional corotating interaction region(CIR)on the transport and acceleration of solar energetic particles(SEPs)is studied.In this work,we discussed how the particle intensity longitudinal and radial dependence might be influenced by the background structures.Moreover,we investigate how the spectral index distribution is modulated by the CIR structure We use the focused transport equation(FTE)to describe the propagation and acceleration of SEPs in a tilt-dipole 3D CIR,generated by the high-resolution 3D magnetohydrodynamic(MHD)model.The forward stochastic differential method is used to solve the FTE.The protons with theE~(-4.4)spectrum from 0.5 to 15 MeV are injected uniformly at the heliographic equator of 0.15 AU.Physical quantities are extracted along each interplanetary magnetic field(IMF)line to show the results.In the tilted-dipole CIR background,if injected from the solar equator at the inner boundary,particles in the slow flow are transported to higher latitudes due to the extension of the IMF lines to higher latitudes.The longitudinal patterns of the particles are dominated by the density of IMF lines.The focusing effect modulates the longitudinal variation of the particle intensity and gives rise to new longitudinal intensity peaks.The adiabatic effect largely increases the intensity fluctuation along the longitude.The structure of the solar wind can also lead to the difference of the indexαin the empirical functionI_(max)=kR~(-α),describing the radial variation of peak intensity according to our simulation.Under the influence of the CIR structure,the indexαvaries from 1.9 to 3.4 at 0.3-1.0 AU.The variation of the solar wind speed should be considered when estimating the radial dependence of the SEP peak intensity.The spectra indices rise near the CIR boundaries and drop near the stream interface(SI).The adiabatic effect makes the spatial variability of the spectral index larger.The spectral index could be similar at different radial distances in the CIR structure. 展开更多
关键词 solar energetic particle(SEP) corotating interaction regions(CIR) magnetohydrodynamic(MHD)
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Classification of single tree decay stages from combined airborne LiDAR data and CIR imagery 被引量:1
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作者 Tsz-Chung Wong Abubakar Sani-Mohammed +3 位作者 Jinhong Wang Puzuo Wang Wei Yao Marco Heurich 《Geo-Spatial Information Science》 CSCD 2024年第6期2076-2091,共16页
Understanding forest health is of great importance for the conservation of the integrity of forest ecosystems.The monitoring of forest health is,therefore,indispensable for the long-term conservation of forests and th... Understanding forest health is of great importance for the conservation of the integrity of forest ecosystems.The monitoring of forest health is,therefore,indispensable for the long-term conservation of forests and their sustainable management.In this regard,evaluating the amount and quality of dead wood is of utmost interest as they are favorable indicators of biodiversity.Apparently,remote sensing-based Machine Learning(ML)techniques have proven to be more efficient and sustainable with unprecedented accuracy in forest inventory.However,the application of these techniques is still in its infancy with respect to dead wood mapping.This study,for the first time,automatically categorizing individual coniferous trees(Norway spruce)into five decay stages(live,declining,dead,loose bark,and clean)from combined Airborne Laser Scanning(ALS)point clouds and color infrared(CIR)images using three different ML methods−3D point cloud-based deep learning(KPConv),Convolutional Neural Network(CNN),and Random Forest(RF).First,CIR colorized point clouds are created by fusing the ALS point clouds and color infrared images.Then,individual tree segmentation is conducted,after which the results are further projected onto four orthogonal planes.Finally,the classification is conducted on the two datasets(3D multispectral point clouds and 2D projected images)based on the three ML algorithms.All models achieved promising results,reaching overall accuracy(OA)of up to 88.8%,88.4%and 85.9%for KPConv,CNN and RF,respectively.The experimental results reveal that color information,3D coordinates,and intensity of point clouds have significant impact on the promising classification performance.The performance of our models,therefore,shows the significance of machine/deep learning for individual tree decay stages classification and landscape-wide assessment of the dead wood amount and quality by using modern airborne remote sensing techniques.The proposed method can contribute as an important and reliable tool for monitoring biodiversity in forest ecosystems. 展开更多
关键词 Tree decay stages Airborne Laser Scanning(ALS) color infrared imagery(CIR) Machine Learning(ML) dead wood
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粘性CIR过程解的存在唯一性
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作者 张颢严 李慧敏 周也策 《南开大学学报(自然科学版)》 CAS CSCD 北大核心 2024年第2期107-113,共7页
证明了粘性CIR过程解的存在唯一性.通过包含对称局部时的时间变换,从标准的CIR过程得到了粘性CIR过程,因此证明了解的存在性.之后通过一系列时间变换过程,给出了一个关于解唯一性的定理.最后解决了粘性CIR过程的无穷小生成算子及其定义域.
关键词 粘性CIR过程 存在性 唯一性 无穷小生成算子
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分数CIR过程统计行为的数值模拟
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作者 刘博文 张静 陈晓鹏 《应用概率统计》 CSCD 北大核心 2024年第1期1-17,共17页
Cox-Ingersoll-Ross (CIR)过程在金融领域有着重要的应用,本文主要对分数CIR过程的统计行为进行了模拟和探讨.由于该过程不存在解析解,拟采用两种不同随机函数wfbm和fbmld来模拟分数布朗运动,利用Euler-Maruyama (EM)方法模拟分数CIR过... Cox-Ingersoll-Ross (CIR)过程在金融领域有着重要的应用,本文主要对分数CIR过程的统计行为进行了模拟和探讨.由于该过程不存在解析解,拟采用两种不同随机函数wfbm和fbmld来模拟分数布朗运动,利用Euler-Maruyama (EM)方法模拟分数CIR过程的期望和方差.由于分数CIR过程的分布不能用福克–普朗克方程(Fokker-Planck equation)的解来表示,文章模拟了分数CIR过程的经验分布,并得到了随时间变化时的经验分布变化情况.为了进一步验证该Euler-Maruyama(EM)算法和比较两种随机函数的优越性,模拟了可以转化为向后欧拉法的分数Cox-Ingersoll-Ross(CIR)模型和具有解析解的分数Ornstein-Uhlenbeck (OU)模型,通过比较图像和数据,发现采用函数fbmld模拟的分数CIR过程的期望以及方差和理论上的期望以及方差具有较强的拟合程度. 展开更多
关键词 CIR过程 OU过程 EM方法 分数布朗运动 随机微分方程
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CIR设备数据无线传输及智能分析系统研究
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作者 张孟 欧盛芬 《铁路通信信号工程技术》 2024年第6期70-77,共8页
旨在解决铁路行业中机车综合无线通信(CIR)设备数据下载和分析过程中存在的问题,针对现有数据下载耗时长、人工分析困难等挑战,提出一套CIR设备数据无线传输及智能分析系统的设计方案。当前CIR设备记录单元数据下载和分析仍然依赖人工操... 旨在解决铁路行业中机车综合无线通信(CIR)设备数据下载和分析过程中存在的问题,针对现有数据下载耗时长、人工分析困难等挑战,提出一套CIR设备数据无线传输及智能分析系统的设计方案。当前CIR设备记录单元数据下载和分析仍然依赖人工操作,存在时间滞后、效率低下的情况,对铁路运输安全构成潜在风险。设计的系统架构分为车载采集设备和地面智能分析系统两部分,通过现有的LMD系统进行通信连接。车载采集设备通过专用线缆与机车CIR设备记录单元监测接口连接,数据通过无线网络传输至地面服务器。地面智能分析系统实现数据存储、智能分析、报表统计等功能,基于大数据技术和分布式架构,提高数据处理和分析效率。系统中的智能分析模块能够实现设备状态远程监测、智能分析、设备运用情况智能评分和标准化检测作业评分等功能。经过现场应用验证,该系统可以缩短数据下载、分析时间,减少人工成本,提前预防CIR设备故障,确保铁路运输安全和效率。 展开更多
关键词 CIR设备 数据无线传输 智能分析 设备质量评分 标准作业评分
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时间分数阶 CIR 模型下回望期权的定价问题
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作者 杜云康 许作良 《金融》 2024年第4期1539-1551,共13页
本文主要研究了时间分数阶 CIR (Cox-Ingersoll-Ross) 模型下回望期权的定价问题。传统的 CIR 模型由于其对长期记忆效应的忽视,已无法充分描述金融市场中的一些复杂现象。因此,本 文引入了时间分数阶导数,以捕捉金融市场中更为复杂的... 本文主要研究了时间分数阶 CIR (Cox-Ingersoll-Ross) 模型下回望期权的定价问题。传统的 CIR 模型由于其对长期记忆效应的忽视,已无法充分描述金融市场中的一些复杂现象。因此,本 文引入了时间分数阶导数,以捕捉金融市场中更为复杂的动态特性。在研究过程中,本文首先利 用 It^o 引理和 ∆-对冲原理对时间分数阶 CIR 模型进行了数学推导,建立了回望期权定价的理论 框架。然后,本文在时间方向与空间方向上使用了有限差分方法对定价公式进行了数值离散处理。 最后,本文进行了数值实验,数值实验的结果验证了所提出方法的有效性。 展开更多
关键词 CIR 模型 时间分数阶 期权定价 数值方法
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标准布朗运动驱动的 CIR 模型梯形数值方法
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作者 陈凯旋 《应用数学进展》 2024年第1期444-452,共9页
本文针对标准布朗运动驱动的Cox–Ingersoll–Ross (CIR)模型探讨了梯形数值方法的强收敛性。通过Lamperti变换, 将CIR模型转换为具有局部Lipschitz条件的漂移项和具有全局Lipschitz条件的扩散项的新方程. 在适当的条件下,证明了新方程... 本文针对标准布朗运动驱动的Cox–Ingersoll–Ross (CIR)模型探讨了梯形数值方法的强收敛性。通过Lamperti变换, 将CIR模型转换为具有局部Lipschitz条件的漂移项和具有全局Lipschitz条件的扩散项的新方程. 在适当的条件下,证明了新方程梯形数值方法的保正性和强收敛阶,并通过 Lamperti 逆变换得到了CIR模型数值解的强收敛阶。最后,利用数值模拟结果验证了理论分析。 展开更多
关键词 随机微分方程 Lamperti变换 梯形数值方法 CIR模型 强收敛阶
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发展中国智能铁路系统的若干思考 被引量:15
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作者 严余松 《交通运输工程学报》 EI CSCD 2001年第4期15-20,26,共7页
总结了智能交通系统 ITS的发展状况和智能铁路系统的国内外研究情况 ,提出了中国智能铁路系统 CIRS的基本组成和总体结构。在此基础上 ,分析了中国智能铁路系统 CIRS的基本特征和所具有的优势 ,指出了中国智能铁路系统 CIRS的若干关键技... 总结了智能交通系统 ITS的发展状况和智能铁路系统的国内外研究情况 ,提出了中国智能铁路系统 CIRS的基本组成和总体结构。在此基础上 ,分析了中国智能铁路系统 CIRS的基本特征和所具有的优势 ,指出了中国智能铁路系统 CIRS的若干关键技术 ,并对 GPS在智能铁路系统中的应用进行了讨论 ,最后提出了发展中国铁路智能系统 展开更多
关键词 外国 智能交通系统 中国 智能铁路系统 组成 总体结构 ITS cirs GPS 发展
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基于LMD的机车CIR数据实时下载技术研究
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作者 孟琳 王军 +2 位作者 杨贺 杨启鹏 冀书晓 《中国科技纵横》 2024年第24期62-64,共3页
近年来,通信网络和大数据技术日趋成熟,将通信网络和大数据技术应用于铁路机车设备监测相关的信息化建设,有助于更好地应对来自铁路的设备运用效率、设备质量监测、运用安全等方面的挑战。本文以CIR设备数据实时下载为切入点,提出了基于... 近年来,通信网络和大数据技术日趋成熟,将通信网络和大数据技术应用于铁路机车设备监测相关的信息化建设,有助于更好地应对来自铁路的设备运用效率、设备质量监测、运用安全等方面的挑战。本文以CIR设备数据实时下载为切入点,提出了基于LMD的机车CIR设备监测、数据实时下载的解决方案,并对CIR数据实时传输关键技术和预期应用效果进行了简要介绍。 展开更多
关键词 CIR 设备监测 LMD LAIS
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中老年急性缺血性脑卒中患者共病状态与卒中后功能恢复的相关性研究 被引量:54
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作者 刘玉华 郭富强 +1 位作者 王建红 杨璟 《中国全科医学》 CAS 北大核心 2020年第4期453-458,共6页
背景中老年急性缺血性脑卒中患者同时患有多种慢性病,并且这种共病状态对患者的预后功能恢复产生较大影响。目的探讨中老年急性缺血性脑卒中患者共病状态与卒中后出院美国国立卫生研究院卒中量表(NIHSS)评分及出院3个月后改良Rankin量表... 背景中老年急性缺血性脑卒中患者同时患有多种慢性病,并且这种共病状态对患者的预后功能恢复产生较大影响。目的探讨中老年急性缺血性脑卒中患者共病状态与卒中后出院美国国立卫生研究院卒中量表(NIHSS)评分及出院3个月后改良Rankin量表(mRS)评分的关系。方法收集2016年1月-2018年6月在温江区人民医院神经内科住院的≥45岁的急性缺血性脑卒中患者293例,记录其临床信息、疾病累积评分量表(CIRS)评分、共病指数、严重指数、入院及出院的NIHSS评分(以出院NIHSS评分为0~2分或较入院时减少≥4分为出院时好转)、出院3个月后m RS评分(以出院3个月后m RS评分≤2分为预后良好)等资料。分析患者共病状态与出院好转与否及出院3个月随访卒中后功能恢复的关系。结果最终纳入的264例患者的CIRS平均得分为(9.58±5.04)分、严重指数为(0.67±0.36)、共病指数为(3.30±1.83)、入院NIHSS得分为6(4,11)分、出院NIHSS得分为3(1,8)分。不同CIRS评分分层患者的年龄、严重指数、共病指数、入院NIHSS评分、出院NIHSS评分、住院天数、出院3个月后mRS评分比较,差异有统计学意义(P<0.05);出院时是否好转患者的CIRS评分分层比较,差异有统计学意义(P<0.05);不同预后情况患者的CIRS评分分层、年龄、严重指数、共病指数、出院NIHSS评分、住院天数比较,差异有统计学意义(P<0.05)。出院NIHSS评分、入院NIHSS评分、严重指数、CIRS评分、心房颤动、共病指数、年龄、住院天数与患者出院3个月后m RS评分呈正相关;高血压与患者出院3个月后m RS评分呈负相关(P<0.05)。结论中老年急性缺血性脑卒中患者共病状态与卒中后出院NIHSS评分、3个月后m RS评分有密切的关系。CIRS评分较低、年龄较小、共病指数和严重指数低的患者预后良好。 展开更多
关键词 急性缺血性脑卒中 共病状态 预后 cirs评分 NIHSS评分 mRS评分
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基于Vasicek和CIR模型中的中国货币市场利率行为实证分析 被引量:84
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作者 谢赤 吴雄伟 《中国管理科学》 CSSCI 2002年第3期22-25,共4页
本文引进了一种全新的计量经济学方法———广义矩估计法 ,并通过MATLAB程序 ,使用中国货币市场的数据对Vasicek和CIR模型进行了参数估计 ,与以前的估计方法相比 ,得出的结果都相当显著 ,从而能更好的了解中国货币市场利率行为的特点。
关键词 Vasicek CIR模型 利率行为 利率期限结构模型 广义矩估计法 中国 货币市场
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