A gated recurrent unit model to predict Poisson’s ratio using deep learning

Static Poisson’s ratio(vs)is crucial for determining geomechanical properties in petroleum applications,namely sand production.Some models have been used to predict vs;however,the published models were limited to specific data ranges with an average absolute percentage relative error(AAPRE)of more than 10%.The published gated recurrent unit(GRU)models do not consider trend analysis to show physical behaviors.In this study,we aim to develop a GRU model using trend analysis and three inputs for predicting n s based on a broad range of data,n s(value of 0.1627-0.4492),bulk formation density(RHOB)(0.315-2.994 g/mL),compressional time(DTc)(44.43-186.9 μs/ft),and shear time(DTs)(72.9-341.2μ s/ft).The GRU model was evaluated using different approaches,including statistical error an-alyses.The GRU model showed the proper trends,and the model data ranges were wider than previous ones.The GRU model has the largest correlation coefficient(R)of 0.967 and the lowest AAPRE,average percent relative error(APRE),root mean square error(RMSE),and standard deviation(SD)of 3.228%,1.054%,4.389,and 0.013,respectively,compared to other models.The GRU model has a high accuracy for the different datasets:training,validation,testing,and the whole datasets with R and AAPRE values were 0.981 and 2.601%,0.966 and 3.274%,0.967 and 3.228%,and 0.977 and 2.861%,respectively.The group error analyses of all inputs show that the GRU model has less than 5% AAPRE for all input ranges,which is superior to other models that have different AAPRE values of more than 10% at various ranges of inputs.

Topology Optimization of Metamaterial Microstructures for Negative Poisson’s Ratio under Large Deformation Using a Gradient-Free Method

Negative Poisson’s ratio(NPR)metamaterials are attractive for their unique mechanical behaviors and potential applications in deformation control and energy absorption.However,when subjected to significant stretching,NPR metamaterials designed under small strain assumption may experience a rapid degradation in NPR performance.To address this issue,this study aims to design metamaterials maintaining a targeted NPR under large deformation by taking advantage of the geometry nonlinearity mechanism.A representative periodic unit cell is modeled considering geometry nonlinearity,and its topology is designed using a gradient-free method.The unit cell microstructural topologies are described with the material-field series-expansion(MFSE)method.The MFSE method assumes spatial correlation of the material distribution,which greatly reduces the number of required design variables.To conveniently design metamaterials with desired NPR under large deformation,we propose a two-stage gradient-free metamaterial topology optimization method,which fully takes advantage of the dimension reduction benefits of the MFSE method and the Kriging surrogate model technique.Initially,we use homogenization to find a preliminary NPR design under a small deformation assumption.In the second stage,we begin with this preliminary design and minimize deviations in NPR from a targeted value under large deformation.Using this strategy and solution technique,we successfully obtain a group of NPR metamaterials that can sustain different desired NPRs in the range of[−0.8,−0.1]under uniaxial stretching up to 20% strain.Furthermore,typical microstructure designs are fabricated and tested through experiments.The experimental results show good consistency with our numerical results,demonstrating the effectiveness of the present gradientfree NPR metamaterial design strategy.

Study of Quality Standards of Xiao’er Qingre Enema Preparation in Hospitals

Objective:To establish the quality standards for the preparation of Xiao’er Qingre enema in hospitals.Method:Thin-layer chromatography(TLC)was used to identify Radix Isatidis and Glycyrrhizae in the prescription.The content of(R,S)-Goitrin was determined by high-performance liquid chromatography(HPLC).Results:In TLC identification,there was no interference between the negative controls of Radix Isatidis and glycyrrhizae,and the spots were well-separated.The HPLC results of(R,S)-Goitrin showed a good linear relationship between the peak area and concentration within the range of 0.476-95.2μg·mL-1(r=0.9999).Conclusion:The TLC and HPLC methods established in this experiment are simple,reproducible,and specific,making them suitable for the quality control Xiao’er Qingre enema preparation in hospitals.

基于S-R和分解定理的二维几何非线性问题的虚单元法求解

应变-旋转(Strain-Rotation,S-R)和分解定理为分析几何非线性问题提供了合理可靠的理论基础,但用有限元求解时会遇到大变形发生后的网格畸变问题。近年提出的虚单元法(Virtual element method,VEM)适用于一般的多边形网格,因此,该文尝试使用一阶虚单元求解基于S-R和分解定理的二维几何非线性问题,以克服网格畸变的影响。基于重新定义的多项式位移空间基函数,推演获得一阶虚单元分析线弹性力学问题时允许位移空间向多项式位移空间的投影表达式;按照虚单元法双线性格式的计算规则,分析处理基于更新拖带坐标法和势能率原理的增量变分方程;进而建立离散系统方程及其矩阵表达形式,并编制MATLAB求解程序;采用常规多边形网格和畸变网格,应用该文算法分析均布荷载下的悬臂梁和均匀内压下的厚壁圆筒变形。结果与已有文献和ANSYS软件的对比表明:该文算法在两种网格中均可有效执行且具备足够数值精度。总体该文算法为基于S-R和分解定理的二维几何非线性问题求解提供了一种鲁棒方法。

Ⅰ导联R/(R+S)对胸前V3导联移行流出道室性心律失常起源部位的鉴别价值

目的:探索鉴别胸前V3导联移行流出道室性心律失常(OT-VA)起源部位的体表心电图指标。方法:连续选择2017年1月至2022年8月行导管射频消融术的胸前V3导联移行OT-VA患者65例。比较左室流出道起源组(LVOT组)和右室流出道起源组(RVOT组)室性心律失常发作时体表心电图QRS波振幅及相关指标的差异,选择差异有统计学意义的指标,绘制ROC曲线评价所选取指标鉴别OT-VA起源部位的效能。结果:LVOT组11例,RVOT组54例,两组间差异有统计学意义且ROC曲线下面积(AUC)最大的指标为Ⅰ导联R波/(R+S)波振幅比[R/(R+S)],其鉴别OT-VA起源部位的AUC(95%CI)为0.949(0.894~1.000),截断值为0.50。Ⅰ导联R/(R+S)<0.50诊断胸前V3导联移行LVOT起源OT-VA的敏感度、特异度和准确度分别为0.909、0.944和0.938。结论:Ⅰ导联R/(R+S)<0.50可准确鉴别LVOT起源的胸前V3导联移行OT-VA。

基于REOF的不同量级降雨侵蚀力时空变化——以重庆市为例

研究重庆市不同地理分区内各量级降雨侵蚀力的时空变化特征,为该地区进行更加精准的区域性水土流失防治工作提供理论依据。选取1981-2020年重庆市31个站点逐日降雨数据,利用旋转经验正交函数(Rotated Empirical Orthogonal Function,REOF)对降雨侵蚀力进行地理分区,并结合R/S、5年滑动平均、Mann-Kendall检验等方法,分析各分区不同量级降雨侵蚀力时空变化。结果表明:①重庆市降雨侵蚀力可分为6个地理区域(Ⅰ-Ⅵ区);②重庆市多年平均降雨侵蚀力为5784.04 MJ·mm/(hm^(2)·h·a),不同降雨侵蚀力从大到小依次为:大雨、暴雨、中雨、大暴雨;③大雨侵蚀力在Ⅰ-Ⅲ区和Ⅴ-Ⅵ区占主导优势,暴雨侵蚀力在Ⅳ区占主导优势。各分区中,中雨、大雨及暴雨侵蚀力主要集中在5-9月,大暴雨侵蚀力集中在6-8月;④各区不同量级降雨侵蚀力年际变化从小到大依次为:中雨、大雨、暴雨、大暴雨;同一量级降雨侵蚀力的整体变化趋势均不显著;Hurst指数表明,中雨侵蚀力在Ⅰ和Ⅴ区、大雨侵蚀力在Ⅱ和Ⅴ区、大暴雨侵蚀力在Ⅰ和Ⅲ区呈强持续上升趋势;⑤中雨、大雨及大暴雨侵蚀力在渝东南、渝东北占主导优势,暴雨侵蚀力在渝西以及重庆中部占主导优势,且Ⅰ区酉阳和秀山、Ⅱ区开州、Ⅲ区北碚和铜梁、Ⅳ区璧山和永川、Ⅴ区巫溪和云阳及Ⅵ区忠县是不同量级降雨侵蚀力的高峰中心。通过对重庆各分区不同量级降雨侵蚀力的分析,明确了可能引起土壤侵蚀的主要雨型、高发时期和潜在风险较高的地区,可为区域水土流失动态监测和水土保持措施的合理制定提供参考。

基于S-O-R模型的视觉营销对消费者购买意愿的影响研究——以红色文创网店为例

为提高红色文创网店的点击转化率,文章从消费者视角出发,研究影响消费者购买意愿的视觉因素。基于S-O-R模型理论,构建红色文创网店视觉营销对消费者购买意愿因素的理论模型。利用S-O-R模型分析了红色文创网店视觉营销中的商品形象、界面形象以及品牌视觉形象对顾客感知价值及顾客购买意向的影响。通过设计量表和调查问卷进行实证研究,并结合结构方程模型加以论证,得出品牌视觉形象和界面形象是影响消费者购买意愿的关键因素,为设计师和红色文创品牌进行网店设计提供了一定的理论参考和建议。

信息性还是娱乐性?——基于S-O-R模型的政务短视频媒介使用及其效果研究

政务短视频是时下较受欢迎的政务新媒体,用户主要在信息性和娱乐性两个维度对其接触和使用。基于S-O-R模型的调查分析表明,政务短视频媒介使用对媒介可信度、用户持续使用意愿主要产生间接影响,且通过政治知识和绩效感知两个变量产生中介效应。其中,政务短视频的使用频率和信息性使用透过政治知识变量对媒介可信度产生显著的正向影响,但娱乐性使用的作用机制为负向。政治知识对用户持续使用意愿的效果路径无显著影响。绩效感知变量是政务短视频使用频率、信息性使用对持续使用意愿产生正向影响的有效中介变量,但对媒介可信度的效果路径无中介作用。说明在视觉化中国政治传播语境中,政务短视频虽不可避免地需要使用娱乐性元素构建内容、获得用户,但根本上仍然要以“信息性”制胜,相应调整内容供给策略和运营策略,以获得积极的效果。

铝二次电池用RGO-S电极材料制备与性能研究

以氧化石墨烯与硫代硫酸钠为原料,通过一步水热法,制备还原氧化石墨烯-硫(RGO-S)电极,通过XRD、XPS、SEM、TEM、恒流充放电测试等手段对电极进行分析。结果如下:在RGO-S中硫元素主要为单质,单质硫与还原氧化石墨烯之间主要是以物理吸附的方式结合,主要以S2p3形态存在,小部分以S2p1形态存在。硫元素含量越高,初次充放电容量越高,循环性能越差。硫碳质量比为3:7的RGO-S复合材料具有最优性能,经过120次的充放电循环后放电容量回复到92%左右,在高倍率电流密度下放电容量保持在58.83mAh/g。

R.S.托马斯诗歌中的反田园书写

R.S.托马斯的诗歌展现了威尔士乡村一系列反田园特质,包括几乎绝望的风景、花园里的机器和自然界弱肉强食的暴力法则。这种现实主义的反田园书写反映了托马斯的民族主义情结、反现代主义和生态主义的立场。通过探讨田园与反田园的含义,分析托马斯诗歌中的反田园书写及其现实关怀,有助于挖掘他积极的入世态度和道德情怀。

达人主播直播带货对消费者购买意愿的双路径影响——基于SOR及ELM模型的分析

文章基于SOR模型和ELM模型,研究了达人主播直播带货营销对消费者购买意愿的影响机理。该研究发现,消费者购买意愿通过中心路径和边缘路径被影响,中心路径因素为信息质量和促销激励,而边缘路径因素为达人主播的专业性、知名度和社会临场感。此外,消费者的感知信任和感知价值对其购买意愿具有显著正向影响,并在不同因素之间起中介作用。本研究结果提供了一个包括感知信任和感知价值双路径的中介影响模型框架,为未来研究该领域提供了新的思路和实证基础。

基于16S rDNA测序分析独活寄生汤对膝骨关节炎大鼠肠道菌群的影响

目的通过16S r DNA测序探讨独活寄生汤(Duhuo Jisheng Decoction,DHJSD)在调控肠道菌群以治疗膝骨关节炎(knee osteoarthritis,KOA)中的潜在机制。方法选取18只SD大鼠,随机分为模型组(关节腔内注射50μL浓度为40 mg/mL的碘乙酸钠)、空白组(灌胃等量生理盐水)以及DHJSD组(造模方法与模型组相同,灌胃独活寄生汤16.5 g/kg),每组6只。造模2周后开始干预,每天灌胃1次,持续4周,并观察其一般情况。给药结束后进行取材,通过HE染色观察软骨变化。ELISA法检测血清白细胞介素(interleukin,IL)-1β、IL-6、IL-17和肿瘤坏死因子-α(tumor necrosis factor-α,TNF-α)炎症因子水平。RT-qPCR检测滑膜中核因子κB p65(nuclear factor-κB p65,NF-κB p65)、雷帕霉素靶蛋白(mechanistic target of rapamycin,mTOR)、AMP激活蛋白激酶(AMP-activated protein kinase,AMPK)和磷脂酰肌醇-3-激酶(phosphatidylinositol 3-kinase,PI3K)的相对表达量。取肠道粪便进行16S rDNA测序分析肠道微生物群的差异。结果相比空白组,模型组大鼠的活动减少,毛发失去光泽,摄食量和饮水量减少。相比模型组,DHJSD组大鼠的活动性、毛发光泽和饮食均明显改善。HE染色结果表明,DHJSD能有效改善软骨损伤,减轻纤维化和炎症反应。ELISA结果表明,相比空白组,模型组的IL-1β、IL-6、IL-17和TNF-α水平升高(P<0.01)。相比模型组,DHJSD组IL-1β、TNF-α水平降低(P<0.01)。RT-qPCR结果表明,相比空白组,模型组NF-κB p65、mTOR和AMPK的相对表达量升高(P<0.05)。相比模型组,DHJSD组mTOR的相对表达量降低(P<0.05)。16S r DNA测序结果表明,DHJSD可以调控KOA大鼠的肠道菌群结构,并影响菌群的α和β多样性。乳球菌属(Lactococcus)和肠杆菌属(Enterorhabdus)分别是DHJSD组和模型组中富集最显著的菌群。结论DHJSD能有效修复软骨损伤,减缓KOA的进展,其机制可能与调控肠道菌群、维护肠道屏障完整性以及减少免疫炎症反应有关。

Effect of C/S Ratio on Morphology and Structure of Hydrothermally Synthesized Calcium Silicate Hydrate

The samples of the C-S-H series were synthesized by hydrothermal reaction of fumed silica, CaO and deionized water at initial C/S ratios between 1.0-1.7. Phase composition and structural and morphology characteristics of C-S-H samples were analyzed by XRD, IR and SEM. The experimental results showed that the d-spacing of （002）, （110） and （020） decreased, the d-spacing of （200） increased, and the d-spacing of （310） varied randomly, the polymerization of silica tetrahedra of C-S-H decreased, and morphology of C-S-H samples varied from sheet shapes to long reticular fibers as C/S ratio increased.

Measurement of Young's Modulus and Poisson's Ratio of Thermal Barrier Coatings

In gas turbines, thermal barrier coatings （TBCs） applied by air plasma spraying are widely used to lower the temperature of hot components. To analyze the characteristics of TBCs such as residual stress, bond strength, fracture toughness, and crack propagation ratio, the Young＇s modulus and Poisson＇s ratio are important parameters. For TBC is a brittle and thin film, it is desirable to evaluate those properties while the coatings are bonded to a substrate. An atmospheric plasma spray MCrAIY bond coat and Yttria stabilized zirconia （YSZ） top coat are deposited onto a nickel-base superalloy GH150 substrate. The Young＇s modulus and Poisson＇s ratio are measured by cantilever beam bending with NDI. The method will be developed to test the Young＇ s modulus and Poisson ratio of other multilayer systems.

Q-factor estimation in CMP gather and the continuous spectral ratio slope method

The attenuation factor or quality factor(Q-factor or Q) has been used to measure the energy attenuation of seismic waves propagating in underground media. Many methods are used to estimate the Q-factor. We propose a method to calculate the Q-factor based on the prestack Q-factor inversion and the generalized S-transform. The proposed method specifies a standard primary wavelet and calculates the cumulative Q-factors; then, it finds the interlaminar Q-factors using the relation between Q and offset(QVO) and the Dix formula. The proposed method is alternative to methods that calculate interlaminar Q-factors after horizon picking. Because the frequency spectrum of each horizon can be extracted continuously on a 2D time–frequency spectrum, the method is called the continuous spectral ratio slope(CSRS) method. Compared with the other Q-inversion methods, the method offers nearly effortless computations and stability, and has mathematical and physical significance. We use numerical modeling to verify the feasibility of the method and apply it to real data from an oilfield in Ahdeb, Iraq. The results suggest that the resolution and spatial stability of the Q-profile are optimal and contain abundant interlaminar information that is extremely helpful in making lithology and fluid predictions.

Laboratory-scale study of the suppression of PCDD/F emission during coal and MSW co-incineration

The experimental test of co-incinerating Chinese raw municipal solid waste （MSW） and coal in a laboratory-scale tubular reactor was first reported in present study, and the emission of normal gas components and the effects of the S/Cl molar ratio or coal mixing percentages on polychlorinated dibenzo-p-dioxins and dibenzofurans （PCDDs/Fs） emission were investigated and discussed. The results indicated that OCDD was the only PCDD homologues since others like TCDD-HpCDD was hardly detected, while as the categories of PCDF homologues were comparatively much more general. The amount of PCDD was much larger than that of PCDF in all operating conditions. Since ZPCDF/∑PCDD〈〈1, the dominant role of the precursor formation was proven in our experimental conductions. With increasing the coal addition to MSW （from 0 to 16%）, PCDD and PCDF were reduced considerably. Coal and MSW may suppress the PCDD/F emissions efficiently （over 95%） during the MSW incineration process. The PCDD/F suppression results of the present study could be helpful guidance to the industrial application of Chinese MSW and auxiliary coal co-incineration processes. The PCDD/F stack emission data of two industrial incinerators using co-incineration technology in China seem to have a great positive reduction of PCDDs/Fs.

(1R,2S)-2-氟环丙胺对甲苯磺酸盐合成工艺的改进

研究了(1R,2S)-2-氟环丙胺对甲苯磺酸盐的合成工艺。以丁二烯为原料,经过成环、氧化、还原、拆分等反应,设计合成(1S,2S)-2-氟环丙甲酸,通过考察与优化确定了最佳反应条件;进一步制得目标产物(1R,2S)-2-氟环丙胺对甲苯磺酸盐,产物收率达到75%。

R/S ratio in lead Ⅱ, and the prognostic significance of red cell distribution width in acute coronary syndrome

BACKGROUND In spite of developing medical technologies to discover the etiopathogenesis of diseases and developments in the treatment of coronary artery disease, acute coronary syndromes(ACS) continue to be the main cause of mortality and morbidity worldwide. New cardiac biomarkers and techniques are needed to help provide rapid diagnosis in order to evaluate risk in coronary artery patients.AIM To evaluate the effects of R to S ratio(RSR) in the electrocardiograph of patients with ACS, from the point of the arising complication after myocardial infarction(MI), to three-vessel disease(TVD) and mortality.METHODS The data of 1,296 patients with ACS, who presented to the emergency department of our hospital with chest pain between January 2014 and December2018 and were admitted to the cardiology clinic, were retrospectively included in this cross-sectional cohort study. Patients with an RSR value less than I were assigned to group Ⅰ, while those with an RSR value greater than Ⅰ were assigned to group Ⅱ.RESULTS In our study, 466(35.9%) of the 1,296 patients, 357(38.3%) in group 1 and 109(29.9%) in group 2, were female, with a mean age of 61.56 ± 9.42. ST-elevation MI 573(44.2%), unstable angina(UA) 502(38.7%) and non ST-elevation MI 220(17%)were more prevalent in group Ⅰ. Acute anterior MI 263(20.3) in group Ⅰ, and acute inferior MI 184(14.2) in group Ⅱ was higher. Ischemic heart failure was the most common complication. In group Ⅱ, the red cell distribution width(RDW) was 15.42 ± 1.82, the gensini score was 48.39 ± 36.44, the left ventricular ejection fraction was 41.17 ± 10.41, the TVD was 111(8.5), and the mortality rate was 72(5.6), which was significantly higher than group Ⅰ RDW; in MI with ST and nonST-elevation, in TVD, mortality and complications were high and low in UA. In single and multivariate regression analyses, the variables were associated with ACS risk.CONCLUSION RSR levels may be an auxiliary predictive value in ACS in terms of complications developing after MI, TVD, and mortality.

Effects of porosity on seismic velocities, elastic moduli and Poisson's ratios of solid materials and rocks

The generalized mixture rule(GMR) is used to provide a unified framework for describing Young’s(E),shear(G) and bulk(K) moduli, Lame parameter(l), and P- and S-wave velocities(Vpand Vs) as a function of porosity in various isotropic materials such as metals, ceramics and rocks. The characteristic J values of the GMR for E, G, K and l of each material are systematically different and display consistent correlations with the Poisson’s ratio of the nonporous material(v0). For the materials dominated by corner-shaped pores, the fixed point at which the effective Poisson’s ratio(n) remains constant is at v0=0.2, and J(G) > J(E) > J(K) > J(l) and J(G) < J(E) < J(K) < J(l) for materials with v0> 0.2 and v0< 0.2, respectively.J(Vs) > J(Vp) and J(Vs) < J(Vp) for the materials with v0> 0.2 and v0< 0.2, respectively. The effective n increases, decreases and remains unchanged with increasing porosity for the materials with v0< 0.2,v0> 0.2 and v0=0.2, respectively. For natural rocks containing thin-disk-shaped pores parallel to mineral cleavages, grain boundaries and foliation, however, the n fixed point decreases nonlinearly with decreasing pore aspect ratio(a: width/length). With increasing depth or pressure, cracks with smaller a values are progressively closed, making the n fixed point rise and finally reach to the point at v0=0.2.

基于S-O-R理论的儿童沉浸式美育APP研究与设计

目的针对儿童美育发展不平衡的问题,提升儿童美育产品设计,探究界面上、交互上、内容上可行性和实用性,对儿童美育APP的应用研究提出设计策略和实践探讨。方法基于S-O-R理论,结合心流理论与情感层次理论,提出相关模型,并使用SPSS、AMOS软件进行验证。在假设成立的基础上,观察38名4~14岁儿童操作APP实例,提出儿童美育APP的设计要求。结果认知性、设计类因素等能正向影响儿童美育APP的心流体验、满意度和用户黏性。结论儿童设计区别于成年人设计,提升以儿童为中心的设计,通过优化界面设计、音效、交互设计、核心机制等能有效影响儿童对于产品的沉浸式体验。