R-Factor Analysis of Data Based on Population Models Comprising R- and Q-Factors Leads to Biased Loading Estimates

Effects of performing an R-factor analysis of observed variables based on population models comprising R- and Q-factors were investigated. Although R-factor analysis of data based on a population model comprising R- and Q-factors is possible, this may lead to model error. Accordingly, loading estimates resulting from R-factor analysis of sample data drawn from a population based on a combination of R- and Q-factors will be biased. It was shown in a simulation study that a large amount of Q-factor variance induces an increase in the variation of R-factor loading estimates beyond the chance level. Tests of the multivariate kurtosis of observed variables are proposed as an indicator of possible Q-factor variance in observed variables as a prerequisite for R-factor analysis.

Near-surface velocity model construction based on a Monte-Carlo scheme

In tomographic statics seismic data processing, it 1s crucial to cletermme an optimum base for a near-surface model. In this paper, we consider near-surface model base determination as a global optimum problem. Given information from uphole shooting and the first-arrival times from a surface seismic survey, we present a near-surface velocity model construction method based on a Monte-Carlo sampling scheme using a layered equivalent medium assumption. Compared with traditional least-squares first-arrival tomography, this scheme can delineate a clearer, weathering-layer base, resulting in a better implementation of damming correction. Examples using synthetic and field data are used to demonstrate the effectiveness of the proposed scheme.

基于分数阶Zener模型的VTI黏弹性介质频变Q效应数值模拟

黏弹性是地球介质的基本属性.地震波在黏弹性介质中传播会发生振幅衰减和速度频散,导致能量和走时出现变化,影响地震资料的准确成像及解释.因此,研究地震波在黏弹性介质中的传播规律具有重要意义.当前,主要利用常Q(不随频率变化)模型(CQM)表征地震波在地球介质中的传播规律,与高温、高压或含流体介质中观测到的Q随频率变化规律不符.基于分数阶Zener模型(FZM),通过改变分数阶大小,本文研究了Q的频变特性随分数阶的变化规律.考虑速度和Q各向异性,推导了VTI介质的FZM黏弹性波方程,提出了VTI介质的频变Q效应数值模拟方法.数值算例表明:当Q随频率变化较小时,FZM与CQM方法的结果相似;当Q随频率变化剧烈时,FZM与CQM方法的模拟结果差异较大.

基于Q学习的超超临界机组协调系统模型预测控制研究

超超临界机组具有多输入多输出、非线性严重、耦合强、时滞大的特点,其控制系统的设计要求是在保证系统稳定运行的同时,最大限度地提高机组的热效率和功率输出、快速准确地调节机组负荷、确保机组主蒸汽压力和温度在允许范围。通过调整系统模型以及阶段成本,进而获取最优策略。选取强化学习中的Q学习方法。将参数化模型预测控制作为Q学习中的一种新型函数逼近器,通过调整模型预测控制的参数来获取近似最优闭环控制策略以及最优的值函数。将该方法应用到1 GW超超临界锅炉汽轮机协调系统的控制中。在升负荷以及小范围升负荷变化情况下进行仿真。仿真结果表明,与传统模型预测控制方法对比,该方法可以在满足约束的情况下使系统输出值更加准确地到达设定值。

VALIDATION OF NEAR-SURFACE WINDS OBTAINED BY A HYBRID WRF/CALMET MODELING SYSTEM OVER A COASTAL ISLAND WITH COMPLEX TERRAIN

The results from a hybrid approach that combines a mesoscale meteorological model with a diagnostic model to produce high-resolution wind fields in complex coastal topography are evaluated.The diagnostic wind model(California Meteorological Model,CALMET) with 100-m horizontal spacing was driven with outputs from the Weather Research and Forecasting(WRF) model to obtain near-surface winds for the 1-year period from 12 September 2003 to 11 September 2004.Results were compared with wind observations at four sites.Traditional statistical scores,including correlation coefficients,standard deviations(SDs) and mean absolute errors(MAEs),indicate that the wind estimates from the WRF/CALMET modeling system are produced reasonably well.The correlation coefficients are relatively large,ranging from 0.5 to 0.7 for the zonal wind component and from 0.75 to 0.85 for the meridional wind component.MAEs for wind speed range from 1.5 to 2.0 m s-1 at 10 meters above ground level(AGL) and from 2.0 to 2.5 m s-1 at 60 m AGL.MAEs for wind direction range from 30 to 40 degrees at both levels.A spectral decomposition of the time series of wind speed shows positive impacts of CALMET in improving the mesoscale winds.Moreover,combining the CALMET model with WRF significantly improves the spatial variability of the simulated wind fields.It can be concluded that the WRF/CALMET modeling system is capable of providing a detailed near-surface wind field,but the physics in the diagnostic CALMET model needs to be further improved.

基于认知行为模型的启发加速深度Q网络

由于状态-动作空间的扩大或奖励回报稀疏,强化学习智能体在复杂环境下从零开始学习最优策略将更为困难。由此提出基于智能体认知行为模型的启发加速深度Q网络,将符号化的规则表示融入学习网络,动态引导智能体策略学习,解决有效加速智能体学习的问题。该算法将启发知识建模为基于BDI(Belief-Desire-Intention)的认知行为模型,用于产生认知行为知识引导智能体策略学习,设计启发策略网络在线引导智能体的动作选择。GYM典型环境与星际争霸2环境下实验表明,该算法可以根据环境变化动态提取有效的认知行为知识,并借助启发策略网络加速智能体策略收敛。

近地表连续介质区Q值调查应用研究

为了提高地震资料的分辨率,对原始资料进行吸收补偿,需要提高近地表Q模型的精度。针对结构疏松、速度变化快且风化层厚度较大的连续介质近地表对地震波吸收衰减严重的问题,开展了品质因子调查、近地表Q建模等方面研究工作。结果表明:1)井中激发、地表和井底同时接收的双井微测井调查方式,可提高品质因子的精度;2)涵盖了不同风化层速度、厚度且样点数据充分的近地表Q值调查结果保证了Q-v经验公式的统计规律;3)微测井调查的高精度近地表模型为构建层状近地表Q模型奠定了基础;4)连续介质近地表Q模型更加真实地反映了实际近地表Q值的分布规律。以上成果认识,对近地表为连续介质的沙漠、黄土塬等工区提高分辨率地震勘探采集具有一定指导意义。

基于全局响应面算法的Q235B钢的Johnson-Cook模型参数最优

This study investigates the mechanical properties of Q235B steel through quasi-static tests at both room temperature and elevated temperature.The initial values of the Johnson-Cook model parameters are determined using a fitting method.The global response surface algorithm is employed to optimize and calibrate the Johnson-Cook model parameters for Q235B steel under both room temperature and elevated temperature conditions.A simulation model is established at room temperature,and the simulated mechanical performance curves for displacement and stress are monitored.Multiple optimization algorithms are applied to optimize and calibrate the model parameters at room temperature.The global response surface algorithm is identified as the most suitable algorithm for this optimization problem.Sensitivity analysis is conducted to explore the impact of model parameters on the objective function.The analysis indicates that the optimized material model better fits the experimental values,aligning more closely with the actual test results of material strain mechanisms over a wide temperature range.

Near-surface model reconstruction using pseudo well-surface simultaneous travel time tomographic inversion

The static correction of a near-surface model may be improved by using travel time tomographic inversion.We discuss unfavorable factors in the inversion of surface seismic waves that have been analyzed by the first break.These factors show that sources and geophones arranged on the surface,or close to the surface,give a first break that only includes the direct wave and the up going wave from the down going to up going transition.These up going waves have weak directivity when they arrive at a geophone and so the rays passing through the grids have small directional differences and a narrow azimuth.Drawing lessons from the advantages of Vertical Seismic Profiling(VSP) acquisition mode we describe a pseudo well-surface simultaneous travel time tomographic inversion of a near-surface model.The well depth should be increased in the surface seismic study to produce a pure up going wave,to enhance the verticality of the rays and to increase the azimuth and shorten path length of the rays.Simulations of the effect of well depth on a pseudo well-surface simultaneous travel time tomographic inversion model are reported.The results show that the static corrections are improved significantly when the well depth extends below the weathered or sub-weathered layers.The root mean square error of the statics is 1.14 or 0.93 ms for these two situations,respectively.

Q热动物模型研究概况

Q热是由贝氏柯克斯体感染所致的一种人兽共患病,在自然界中广泛传播。动物模型是研究传染病的病原学、发病机制以及评价疫苗有效性的重要工具。近年来,无脊椎动物、啮齿动物和非人灵长类动物等多种动物模型已被用于Q热的相关研究。本文对Q热不同动物模型的研究现状进行了综述,讨论了不同模型的优缺点,总结了未来建模工作的需求和标准。

基于UHPLC-Q-TOF/MS技术分析肿节风总黄酮提取物促进巨核细胞分化的效应成分

目的筛选肿节风总黄酮提取物促进巨核细胞分化的效应成分。方法(1)以人巨核细胞白血病细胞(Dami)与人骨髓基质细胞(HS-5)共培养的方式建立巨核细胞分化障碍模型作为评价体系,实验分组:Dami组(Dami)、对照组(Dami+HS-5)、PMA组[Dami+HS-5+5 ng·mL-1佛波醇12-十四酸酯13-乙酸酯(PMA)]、模型组[Dami+HS-5+1%兔抗大鼠血小板血清(APS)+5 ng·mL-1PMA],培养48 h。采用流式细胞术检测巨核细胞分化成熟表面标记分子CD41a、CD61的表达情况。(2)将49只SD雄性大鼠随机分为空白血浆组、15 min组、30 min组、60 min组、90 min组、120 min组、240 min组,每组7只。各给药组大鼠灌胃肿节风总黄酮提取物1.26 g·kg^(-1),在6个设定时间点(15、30、60、90、120、240 min)采血制备肿节风总黄酮提取物经时含药血浆。(3)采用超高效液相色谱-四极杆串联飞行时间质谱法(UHPLC-Q-TOF/MS)对肿节风总黄酮提取物经时含药血浆进行分析,以峰面积构建肿节风总黄酮提取物经时含药血浆中的化学成分随时间变化量矩阵(X矩阵)。将所采集的6个不同时间点的肿节风总黄酮经时含药血浆对巨核细胞分化成熟障碍模型进行干预,采用流式细胞术检测细胞表面分子CD41a、CD61的表达水平,构建肿节风总黄酮提取物经时含药血浆效应矩阵(Y矩阵)。(4)将X矩阵和Y矩阵数据标准化处理后,采用偏最小二乘法(Partial least squares,PLS)计算分析量效关系,以变量重要性投影(Variable importance for projection,VIP)>1为阈值,筛选与细胞表面分子CD41a、CD61变化相关的效应成分,并进行化学成分鉴定,作为肿节风总黄酮提取物中促进巨核细胞分化的潜在效应成分,最后回归评价体系验证其药效。结果(1)与Dami组比较,对照组Dami细胞表面的CD41a表达水平明显升高(P<0.05)。与对照组比较,PMA组Dami细胞表面的CD41a、CD61表达水平均显著升高(P<0.01)。与PMA组比较,模型组Dami细胞表面的CD41a、CD61表达水平均显著降低(P<0.01)。(2)与空白血浆组比较,15、30、60、90、120、240 min各时间点Dami细胞表面分子CD41a、CD61表达水平均显著升高(P<0.01),且CD41a、CD61均在30 min组表达水平最高。在正、负离子模式下筛选出VIP值>1的潜在效应成分,并选取540.3638@12.25与559.2991@11.53两个成分进行药效学验证。559.2991@11.53被鉴定为胡萝卜苷(Daucosterol,Dau),540.3638@12.25被鉴定为迷迭香酸-4-O-β-D-葡萄糖(Rosmarinic acid 4-O-β-Dglucoside,Ros)。Ros、Dau分别干预巨核细胞分化成熟障碍模型后,与模型组比较,Ros及Dau低、中、高剂量组(40、60、80μg·mL-1)的Dami细胞表面的CD41a、CD61表达水平均显著升高(P<0.05,P<0.01)。结论Ros、Dau可能是肿节风总黄酮提取物促进巨核细胞分化的效应成分。

认知诊断模型Q矩阵修正:完整信息矩阵的作用

Q矩阵是CDM的核心元素之一,反映了测验的内部结构和内容设计,通常由领域专家根据经验进行主观界定,因此需要对可能存在的错误进行修正。本研究提出了一种新的Q矩阵修正方法——基于完整经验交叉相乘信息矩阵的Wald-XPD方法。采用Monte Carlo模拟检验了新方法的表现,并与同类方法进行了比较。研究表明:新开发的Wald-XPD方法在Q矩阵恢复率、保留正确标定属性的比例以及修正错误标定属性的比例这3个主要指标上均有较好的表现,且整体上优于其他方法,尤其是在修正错误标定的属性方面。通过实证数据展示了Wald-XPD方法在Q矩阵修正中的良好表现。总之,本研究为Q矩阵修正提供了有效的方法。

基于Q测度的专利发明人重要性评估方法

[研究目的]跨学科领域合作已成为科研活动的常态,发明人通过合作整合知识元素、共同解决创新难题。处于不同技术领域之间进行技术交融的发明人具有十分重要的桥梁作用,在跨领域的知识交流和互动中作出重大贡献。为了形成更加科学的发明人评价体系,从而对发明人重要性作出更加全面、精准的评估,衡量发明人重要性时需要考虑到发明人在不同技术领域之间的桥梁作用。[研究方法]针对发明人重要性评估方法中存在的缺陷,该研究提出基于Q测度的专利发明人重要性评估方法,用于描述发明人在合作网络中不同学科领域之间的连接作用。以专利转让次数为评价指标,对Q测度、中介中心性、特征向量中心性和PageRank算法的评估效果进行对比分析。[研究结论]结果表明:Q测度具有较好的发明人重要性评估效果,能够较为精准地甄别不同学科领域之间起桥梁作用的重要发明人。

Chaos game representation(CGR)-walk model for DNA sequences

Chaos game representation （CGR） is an iterative mapping technique that processes sequences of units, such as nucleotides in a DNA sequence or amino acids in a protein, in order to determine the coordinates of their positions in a continuous space. This distribution of positions has two features： one is unique, and the other is source sequence that can be recovered from the coordinates so that the distance between positions may serve as a measure of similarity between the corresponding sequences. A CGR-walk model is proposed based on CGR coordinates for the DNA sequences. The CGR coordinates are converted into a time series, and a long-memory ARFIMA （p, d, q） model, where ARFIMA stands for autoregressive fractionally integrated moving average, is introduced into the DNA sequence analysis. This model is applied to simulating real CGR-walk sequence data of ten genomic sequences. Remarkably long-range correlations are uncovered in the data, and the results from these models are reasonably fitted with those from the ARFIMA （p, d, q） model.

Chaos game representation walk model for the protein sequences

A new chaos game representation of protein sequences based on the detailed hydrophobic-hydrophilic （HP） model has been proposed by Yu et al （Physica A 337（2004） 171）. A CGR-walk model is proposed based on the new CGR coordinates for the protein sequences from complete genomes in the present paper. The new CCR coordinates based on the detailed HP model are converted into a time series, and a long-memory ARFIMA（p, d, q） model is introduced into the protein sequence analysis. This model is applied to simulating real CCR-walk sequence data of twelve protein sequences. Remarkably long-range correlations are uncovered in the data and the results obtained from these models are reasonably consistent with those available from the ARFIMA（p, d, q） model.

Bayesian Estimation for the Order of INAR(q)Model

In this paper, we consider the problem of determining the order ofINAR（Q） model on the basis of the Bayesian estimation theory. The Bayesian es-timator for the order is given with respect to a squared-error loss function. The consistency of the estimator is discussed. The results of a simulation study for the estimation method are presented.

Hidden Markov model based epileptic seizure detection using tunable Q wavelet transform

Epilepsy is one of the most prevalent neurological disorders affecting 70 million people worldwide.The present work is focused on designing an efficient algorithm for automatic seizure detection by using electroencephalogram(EEG) as a noninvasive procedure to record neuronal activities in the brain.EEG signals' underlying dynamics are extracted to differentiate healthy and seizure EEG signals.Shannon entropy,collision entropy,transfer entropy,conditional probability,and Hjorth parameter features are extracted from subbands of tunable Q wavelet transform.Efficient decomposition level for different feature vector is selected using the Kruskal-Wallis test to achieve good classification.Different features are combined using the discriminant correlation analysis fusion technique to form a single fused feature vector.The accuracy of the proposed approach is higher for Q=2 and J=10.Transfer entropy is observed to be significant for different class combinations.Proposed approach achieved 100% accuracy in classifying healthy-seizure EEG signal using simple and robust features and hidden Markov model with less computation time.The proposed approach efficiency is evaluated in classifying seizure and non-seizure surface EEG signals.The system has achieved 96.87% accuracy in classifying surface seizure and nonseizure EEG segments using efficient features extracted from different J level.

IMPROVEMENT OF REGIONAL PREDICTION OF SEA FOG ON GUANGDONG COASTLAND USING THE FACTOR OF TEMPERATURE DIFFERENCE IN THE NEAR-SURFACE LAYER

The relationship between the factor of temperature difference of the near-surface layer(T_(1000 hPa)-T_(2m))and sea fog is analyzed using the NCEP reanalysis with a horizontal resolution of l°xl°(2000 to 2011) and the station observations(2010 to 2011).The element is treated as the prediction variable factor in the GRAPES model and used to improve the regional prediction of sea fog on Guangdong coastland.(1) The relationship between this factor and the occurrence of sea fog is explicit:When the sea fog happens,the value of this factor is always large in some specific periods,and the negative value of this factor decreases significantly or turns positive,suggesting the enhancement of warm and moist advection of air flow near the surface,which favors the development of sea fog.(2) The transportation of warm and moist advection over Guangdong coastland is featured by some stages and the jumping among these states.It also gets stronger over time.Meanwhile,the northward propagation of warm and moist advection is quite consistent with the northward advancing of sea fog from south to north along the coastland of China.(3) The GRAPES model can well simulate and realize the factor of near-surface temperature difference.Besides,the accuracy of regional prediction of marine fog,the relevant threat score and Heidke skill score are all improved when the factor is involved.

Arnol＇d＇s Second Nonlinear Stability Theorem for General Multilayer Quasi－geostrophic Model

Arnol'd's second nonlinear stability criterion for motions governed by a general multilayer quasi-geostrophic model is established. The model allows arbitrary density jumps and layer thickness, and at the top and the bottom of the nuid, the boundary condition is either free or rigid. The criterion is obtained by the establishment of the upper bounds of disturbance energy and potential enstrophy in terms of the initial disturbance field.

MODELING v_P AND Q ON EXPLOSION SEISMOLOGY DATA IN NE TIBET

A Sino\|French refraction\|reflection experiment was conducted in October 1998 in the northeastern edge of the Tibetan Plateau from the Qiang Tang through the north Kunlun block.The successive wide\|angle reflection traveltime curves are modeled trying to keep the minimum structure. First results obtained along this 700km transect, show the contrast of crustal structure between the three blocks crossed and the state of the crustal material.North of the Kunlun suture, a change of the Moho depth appears from the Qaidam basin, 55km, to the south approaching the Kunlun range, 65km. But the main crustal characteristic is a great thickness of upper crustal material and the lack of lower crust. This implies a crustal average velocity of 6 2km/s, which is much lower than the worldwide average of 6 45km/s. Interpretations of this crustal column may consider, assuming the crust had been normal that while its upper part thickened the lower one was transported away, underthrust to the south or to depth. Alternatively the velocity in the lower crust may have been changed by metamorphism.