Euler’s First-Order Explicit Method–Peridynamic Differential Operator for Solving Population Balance Equations of the Crystallization Process

Using Euler’s first-order explicit(EE)method and the peridynamic differential operator(PDDO)to discretize the time and internal crystal-size derivatives,respectively,the Euler’s first-order explicit method–peridynamic differential operator(EE–PDDO)was obtained for solving the one-dimensional population balance equation in crystallization.Four different conditions during crystallization were studied:size-independent growth,sizedependent growth in a batch process,nucleation and size-independent growth,and nucleation and size-dependent growth in a continuous process.The high accuracy of the EE–PDDO method was confirmed by comparing it with the numerical results obtained using the second-order upwind and HR-van methods.The method is characterized by non-oscillation and high accuracy,especially in the discontinuous and sharp crystal size distribution.The stability of the EE–PDDO method,choice of weight function in the PDDO method,and optimal time step are also discussed.

Transient response of doubly-curved bio-inspired composite shells resting on viscoelastic foundation subject to blast load using improved first-order shear theory and isogeometric approach

Investigating natural-inspired applications is a perennially appealing subject for scientists. The current increase in the speed of natural-origin structure growth may be linked to their superior mechanical properties and environmental resilience. Biological composite structures with helicoidal schemes and designs have remarkable capacities to absorb impact energy and withstand damage. However, there is a dearth of extensive study on the influence of fiber redirection and reorientation inside the matrix of a helicoid structure on its mechanical performance and reactivity. The present study aimed to explore the static and transient responses of a bio-inspired helicoid laminated composite(B-iHLC) shell under the influence of an explosive load using an isomorphic method. The structural integrity of the shell is maintained by a viscoelastic basis known as the Pasternak foundation, which encompasses two coefficients of stiffness and one coefficient of damping. The equilibrium equations governing shell dynamics are obtained by using Hamilton's principle and including the modified first-order shear theory,therefore obviating the need to employ a shear correction factor. The paper's model and approach are validated by doing numerical comparisons with respected publications. The findings of this study may be used in the construction of military and civilian infrastructure in situations when the structure is subjected to severe stresses that might potentially result in catastrophic collapse. The findings of this paper serve as the foundation for several other issues, including geometric optimization and the dynamic response of similar mechanical structures.

Efficient slope reliability and sensitivity analysis using quantile-based first-order second-moment method

This paper introduces a novel approach for parameter sensitivity evaluation and efficient slope reliability analysis based on quantile-based first-order second-moment method(QFOSM).The core principles of the QFOSM are elucidated geometrically from the perspective of expanding ellipsoids.Based on this geometric interpretation,the QFOSM is further extended to estimate sensitivity indices and assess the significance of various uncertain parameters involved in the slope system.The proposed method has the advantage of computational simplicity,akin to the conventional first-order second-moment method(FOSM),while providing estimation accuracy close to that of the first-order reliability method(FORM).Its performance is demonstrated with a numerical example and three slope examples.The results show that the proposed method can efficiently estimate the slope reliability and simultaneously evaluate the sensitivity of the uncertain parameters.The proposed method does not involve complex optimization or iteration required by the FORM.It can provide a valuable complement to the existing approximate reliability analysis methods,offering rapid sensitivity evaluation and slope reliability analysis.

Estimation of Landfill Gas and Its Renewable Energy Potential from the Polesgo Controlled Landfill Using First-Order Decay (FOD) Models

Methane generation in landfills and its inadequate management represent the major avoidable source of anthropogenic methane today. This paper models methane production and the potential resources expected (electrical energy production and potential carbon credits from avoided CH4 emissions) from its proper management in a municipal solid waste landfill located in Ouagadougou, Burkina Faso. The modeling was carried out using two first-order decay (FOD) models (LandGEM V3.02 and SWANA) using parameters evaluated on the basis of the characteristics of the waste admitted to the landfill and weather data for the site. At the same time, production data have been collected since 2016 in order to compare them with the model results. The results obtained from these models were compared to experimental one. For the simulation of methane production, the SWANA model showed better consistency with experimental data, with a coefficient of determination (R²) of 0.59 compared with the LandGEM model, which obtained a coefficient of 0.006. Thus, despite the low correlation values linked to the poor consistency of experimental data, the SWANA model models methane production much better than the LandGEM model. Thus, despite the low correlation values linked to the poor consistency of the experimental data, the SWANA model models methane production much better than the LandGEM V3.02 model. It was noted that the poor consistency of the experimental data justifies these low coefficients, and that they can be improved in the future thanks to ongoing in situ measurements. According to the SWANA model prediction, in 27 years of operation a biogas plant with 33% electrical efficiency using biogas from the Polesgo landfill would avoid 1,340 GgCO2e. Also, the evaluation of revenues due to electricity and carbon credit gave a total revenue derived from methane production of US$27.38 million at a cost of US$10.5/tonne CO2e.

Gin+GORM通用MIS系统设计

文章旨在介绍一种基于Go语言中的Gin和GORM框架开发的通用管理信息系统(Management Information System,MIS)的设计与实现。MIS系统在各种组织中发挥着关键作用,用于处理、管理和分析各种信息,通过Gin和GORM这两个流行的开源框架,可以快速搭建一个稳定、高效的MIS系统,以满足企业管理信息系统的需求,并提供友好的用户界面和可靠的数据管理。该方案可针对不同的业务需求进行快速定制和扩展功能,具有高度可扩展性和灵活性。

HFACS-MI改进模型在危险化学品仓储事故人因分析中的应用

为了研究危险化学品仓储事故的关键人因,通过人因分析与分类系统-煤矿(Human Factors Analysis and Classification System-Mine,HFACS-MI)改进模型从员工的不安全行为、影响不安全行为的前提条件、监督行为、组织影响和企业外部因素5个层次系统地分析65起危险化学品仓储事故,并运用卡方检验和让步比分析了产生不安全行为的原因和各层次间的内在关系。结果表明,外部管理、组织过程、监督不充分、个人因素、技能差错和违规是导致危险化学品仓储事故发生的重要因素。HFACS-MI改进模型上下层级的人为因素间存在显著的因果关系,且主要的危险化学品仓储事故致因路径共有5条,其中“外部管理因素—组织过程漏洞—监督不充分—个人因素—违规”是最关键的致因路径。改进的HFACS-MI模型可以有效分析危险化学品仓储事故人因因素。

无线紫外光MIMO通信系统信道容量估算方法

无线紫外光通信系统易受大气散射等因素的影响,导致通信信道容量估算准确率较低。为此,提出一种无线紫外光多入多出(Multiple-Input Multiple-Output, MIMO)通信系统信道容量估算方法。根据信道特征,构建无线紫外光MIMO通信系统的信道容量估计模型,获取无线紫外光的单次散射传输特性,利用符号补码式的方法改进空时编码,设定高级检测器中符号的接收能耗,使每个符号保持在标准功率数值范围内,完成通信系统信道检测式编码。根据不同发射角和接收角计算无线紫外光通信的路径损耗比,通过泊松随机分布获得最终通信系统信道容量的估算结果。实验结果表明,所提方法的传输速率可高达8 Mbps,误码率始终低于10-3bit/s,估算准确率在90%以上,估计时间低于4 ms,估算效果好,可为通信行业发展提供理论依据。

STEMI患者外周血单个核细胞中MAPK通路与炎症反应及PCI后无复流的关系

目的 研究ST段抬高型心肌梗死(STEMI)患者外周血单个核细胞(PBMCs)中丝裂原活化蛋白激酶(MAPK)通路与炎症反应及经皮冠状动脉介入术(PCI)后无复流的关系。方法 选取郑州市第七人民医院2021年2月至2022年10月进行PCI治疗的STEMI患者和同期进行体检的健康志愿者,分别作为STEMI组(n=92)和对照组(n=100)。采用荧光定量PCR法检测PBMCs中p38MAPK、JNK的表达水平,根据中位数将STEMI组患者分为p38MAPK、JNK高表达和低表达。检测STEMI患者血清ICAM-1、TNF-α、IL-6含量,评估STEMI患者心肌损伤程度及无复流情况。结果 STEMI组患者PBMCs中p38MAPK、JNK的表达水平高于对照组,差异有统计学意义(t=5.386、5.126,P<0.05);STEMI组中p38MAPK、JNK高表达患者的CK-MB峰值、cTnT峰值及ICAM-1、TNF-α、IL-6含量均高于p38MAPK、JNK低表达患者,差异有统计学意义(t=7.143、4.999、9.528、6.805、6.890、6.226、8.132、7.807、7.162、7.588,P<0.05);STEMI组中无复流患者PBMCs中p38MAPK、JNK的表达水平高于血流正常患者,差异有统计学意义(t=5.208、4.240,P<0.05);经ROC曲线分析,PBMCs中p38MAPK、JNK的表达水平对STEMI患者PCI后无复流具有预测价值(P<0.05)。结论 STEMI患者MAPK通路中p38MAPK、JNK的高表达与炎症反应激活、PCI后无复流有关。

基于多重生物信息学数据库分析Mis18β在膀胱癌组织中的表达及其临床意义

目的:探讨Mis18β基因在膀胱癌组织中的表达、临床意义及在疾病过程中的作用。方法:通过癌症基因组图谱(The Cancer Genome Atlas, TCGA)数据库获得膀胱癌患者Mis18β mRNA测序数据及临床资料数据,通过基因表达综合(Gene Expression Omnibus, GEO)数据库获得膀胱癌Mis18β表达数据,分析Mis18β在膀胱癌组织和癌旁组织中mRNA表达差异及与患者临床病理参数的相关性并进行生存分析,利用基因本体论(Gene Ontology, GO)功能分析以及京都基因与基因组百科全书(Kyoto Encyclopedia of Gene and Genomes, KEGG)通路富集分析探索Mis18β在膀胱癌发生发展中可能的信号通路。收集膀胱癌患者及健康对照者外周血标本,RT-PCR方法验证Mis18β mRNA表达水平的差异。结果:TCGA数据库和GEO数据库分析显示膀胱癌组Mis18β的表达量明显高于对照组(P<0.05)。生存分析提示Mis18β高表达组膀胱癌患者的总生存期明显低于低表达组(P<0.05)。功能富集分析显示Mis18β主要参与细胞有丝分裂,调控细胞周期及DNA复制等过程。膀胱癌患者外周血有核细胞中Mis18β的含量明显高于对照组(P<0.05)。结论:Mis18β在膀胱癌中呈高表达,其表达水平与患者年龄、病理类型、总生存期等临床病理特征存在相关性,为揭示膀胱癌发生发展的分子机制及寻找新的诊断、预后标志物提供了理论基础。

First-order primal-dual algorithm for sparse-view neutron computed tomography-based three-dimensional image reconstruction

Neutron computed tomography(NCT)is widely used as a noninvasive measurement technique in nuclear engineering,thermal hydraulics,and cultural heritage.The neutron source intensity of NCT is usually low and the scan time is long,resulting in a projection image containing severe noise.To reduce the scanning time and increase the image reconstruction quality,an effective reconstruction algorithm must be selected.In CT image reconstruction,the reconstruction algorithms can be divided into three categories:analytical algorithms,iterative algorithms,and deep learning.Because the analytical algorithm requires complete projection data,it is not suitable for reconstruction in harsh environments,such as strong radia-tion,high temperature,and high pressure.Deep learning requires large amounts of data and complex models,which cannot be easily deployed,as well as has a high computational complexity and poor interpretability.Therefore,this paper proposes the OS-SART-PDTV iterative algorithm,which uses the ordered subset simultaneous algebraic reconstruction technique(OS-SART)algorithm to reconstruct the image and the first-order primal–dual algorithm to solve the total variation(PDTV),for sparse-view NCT three-dimensional reconstruction.The novel algorithm was compared with other algorithms(FBP,OS-SART-TV,OS-SART-AwTV,and OS-SART-FGPTV)by simulating the experimental data and actual neutron projection experiments.The reconstruction results demonstrate that the proposed algorithm outperforms the FBP,OS-SART-TV,OS-SART-AwTV,and OS-SART-FGPTV algorithms in terms of preserving edge structure,denoising,and suppressing artifacts.

Consensus problems of first-order dynamic multi-agent systems with multiple time delays

Consensus problems of first-order multi-agent systems with multiple time delays are investigated in this paper. We discuss three cases： 1） continuous, 2） discrete, and 3） a continuous system with a proportional plus derivative controller. In each case, the system contains simultaneous communication and input time delays. Supposing a dynamic multi-agent system with directed topology that contains a globally reachable node, the sufficient convergence condition of the system is discussed with respect to each of the three cases based on the generalized Nyquist criterion and the frequency-domain analysis approach, yielding conclusions that are either less conservative than or agree with previously published results. We know that the convergence condition of the system depends mainly on each agent’s input time delay and the adjacent weights but is independent of the communication delay between agents, whether the system is continuous or discrete. Finally, simulation examples are given to verify the theoretical analysis.

基于互信息和MiniRocket网络的CFST脱空识别

为提高钢管混凝土(concrete filled steel tube,CFST)脱空检测的效率和精度,本文提出了一种基于快速傅里叶变换(fast fourier transform,FFT)、互信息(mutual information,MI)和MiniRocket神经网络的智能识别方法。首先,采用FFT将待测CFST敲击声波时域信号转换为频域信号;其次,采用MI建立频域信号与脱空状态的相关性,提取相关性最大的前30个特征建立数据集,避免了复杂的数学运算和冗余信息;建立MiniRocket深度学习网络,通过使用更少的参数量和更小的特征尺寸,提高分类的速度和精度。最后,考察了模型的噪音鲁棒性,并与其他算法、特征提取方法和识别方法进行对比。结果表明,在不同脱空深度和脱空宽度下,所提的方法在100次重复试验中获得了100%的平均预测精度。在高信噪比下,该方法受影响较小。此外,与其他算法、特征提取方法和识别方法相比,本方法具有更好的预测性能。因此,所提出的方法在未来实际CFST结构的智能脱空识别中具有较大的应用潜力。

青藏高原“MIS 4冰进”的^(10)Be地表暴露测年证据

地貌地层证据及绝对测年数据显示,青藏高原及其周边山地在第四纪期间经历了多次显著的冰川进退。深海氧同位素4阶段(MIS 4)作为末次冰期的一个冰阶,全球平均气温降低、大陆冰量增多、海平面下降,零星测年数据显示青藏高原少数几个山地可能在MIS 4冷期出现冰川前进(本文统一用“MIS 4冰进”来指代冰川漂砾暴露测年数据落在MIS 4的冰川前进,但冰进过程本身不一定完全发生在MIS 4期间)。辽阔的青藏高原面上分布着无数高海拔山地,MIS 4冰进是否广泛存在于其他山地?冰川发育的时间过程又是如何?这些问题仍缺乏系统论述。本文统计并重新计算了青藏高原已发表的落在MIS 4及相近年代的冰川漂砾^(10)Be地表暴露年代,进一步运用P-CAAT方法对暴露年代进行细化分析,最终得到12组(即12个地点)落在MIS 4区间的暴露年代数据,这12个地点主要分布在高原的中南部和西部地区,分析得到:(1)MIS 4时期,青藏高原西部、南部、东部与内部地区曾发生过冰川前进,冰进规模西部最大,南部其次,内部最小,可能主要与冰川补给量的多寡有关。(2)青藏高原MIS 4冰进主要受控于北半球夏季太阳辐射与大气CO_(2)浓度的变化以及北半球中纬度西风带的迁移:MIS 5a至MIS 4早期,太阳辐射逐渐下降至最低值,同期CO_(2)浓度也显著降低,高原气温相应降低,同时,北半球高低纬间温度梯度增大,西风增强且位置南移,可能带来较多冬半年(固态)降水,冰川物质积累量增加,导致冰川前进;MIS 4中、晚期,随着夏季太阳辐射进一步增多及CO_(2)浓度的迅速上升,冰川开始快速退缩。

Visualizing and witnessing first-order coherence,Bell nonlocality and purity by using a quantum steering ellipsoid in the non-inertial frame

A quantum steering ellipsoid(QSE)is a visual characterization for bipartite qubit systems,and it is also a novel avenue for describing and detecting quantum correlations.Herein,by using a QSE,we visualize and witness the first-order coherence(FOC),Bell nonlocality(BN)and purity under non-inertial frames.Also,the collective influences of the depolarizing channel and the non-coherence-generating channel(NCGC)on the FOC,BN and purity are investigated in the QSE formalism.The results reveal that the distance from the center of the QSE to the center of the Bloch sphere visualizes the FOC of a bipartite system,the lengths of the QSE semiaxis visualize the BN,and the QSE's shape and position dominate the purity of the system.One can capture the FOC,BN and purity via the shape and position of the QSE in the non-inertial frame.The depolarizing channel(the NCGC)gives rise to the shrinking and degradation(the periodical oscillation)of the QSE.One can use these traits to visually characterize and detect the FOC,BN and purity under the influence of external noise.Of particular note is that the condition for the QSE to achieve the center of the Bloch sphere cannot be influenced by the depolarizing channel and the NCGC.The characterization shows that the conditions for the disappearance of the FOC are invariant under the additional influences of the depolarizing channel and NCGC.

First-order Derivative Spectrophotometry for the Determination of Vitamin C in Medicament

A novel method for the determination of vitamin C（Vc） is proposed in this article. After the reaction with Folin-Ciocalteau reagent at ambient temperature, Vc solution was scanned at 750--1100 nm, and its first-order derivative spectrum were obtained from the original spectrum. The values of derivative selected at 995 nm were used for determination. It was proved that Vc could quickly react with Folin-Ciocalteau reagent within 5 min and the product was quite stable for a long time. The conditions required for this method is not very complicated, its precision and accuracy are similar to those of the iodometric titration described in Chinese Pharmacopoeia, and the limit of detection is 0.312 μg/mL. The determination of the results of vitamin C tablet, pill, and injection demonstrates that this method has wide pharmaceutical applications.

Investigation of magnetization reversal and domain structures in perpendicular synthetic antiferromagnets by first-order reversal curves and magneto-optical Kerr effect

Perpendicular synthetic-antiferromagnet(p-SAF) has broad applications in spin-transfer-torque magnetic random access memory and magnetic sensors. In this study, the p-SAF films consisting of (Co/Ni)3]/Ir(tIr)/[(Ni/Co)3are fabricated by magnetron sputtering technology. We study the domain structure and switching field distribution in p-SAF by changing the thickness of the infrared space layer. The strongest exchange coupling field(Hex) is observed when the thickness of Ir layer(tIr) is 0.7 nm and becoming weak according to the Ruderman–Kittel–Kasuya–Yosida-type coupling at 1.05 nm,2.1 nm, 4.55 nm, and 4.9 nm in sequence. Furthermore, the domain switching process between the upper Co/Ni stack and the bottom Co/Ni stack is different because of the antiferromagnet coupling. Compared with ferromagnet coupling films, the antiferromagnet samples possess three irreversible reversal regions in the first-order reversal curve distribution.With tIrincreasing, these irreversible reversal regions become denser and smaller. The results from this study will help us understand the details of the magnetization reversal process in the p-SAF.

膀胱癌组织中MIS18BP1的表达及临床意义

目的探讨MIS18BP1在膀胱癌中的表达、与临床病理参数相关性及临床意义。方法TCGA、GEO数据库分析MIS18BP1在肿瘤和对照组中mRNA表达并经qRT-PCR验证;UALCAN在线数据库分析MIS18BP1表达及与临床病理参数、免疫细胞浸润程度相关性;免疫组织化学分析MIS18BP1在膀胱癌中的表达及与临床病理特征的关系;ROC曲线评价MIS18BP1 mRNA对膀胱癌的诊断价值。结果生物信息学分析及qRT-PCR结果显示,与对照组相比较,MIS18BP1 mRNA在膀胱癌中表达增加(P<0.05);免疫组织化学结果表明膀胱癌MIS18BP1蛋白阳性率显著增高(P<0.05),且与肿瘤临床分期、浸润深度及淋巴结转移相关(P<0.05);免疫浸润分析显示MIS18BP1与膀胱癌中免疫细胞浸润相关。结论MIS18BP1基因和蛋白在膀胱癌中表达水平增高,可能通过影响免疫细胞浸润调控膀胱癌的发生发展。

对MIS结构热弛豫时间的分析计算

对MIS(金属-绝缘层-半导体)结构从深耗尽过渡至强反型状态所需的热弛豫时间进行了研究。通过建立较教科书更精确的模型,对热弛豫时间τth与深耗尽时耗尽区宽度x d0、强反型时耗尽区最大宽度x dm、耗尽区内少子净产生率G和掺杂浓度N D等关键物理量之间的关联进行了推导,并基于MEDICI平台对推导结果完成了仿真验证,从而加强了学生对半导体表面效应的理解,也利于他们未来从事半导体方面的创新研究。

血清miR-590联合粪便钙卫蛋白对溃疡性结肠炎的诊断价值及其与内镜下疾病活动度的相关性

目的 探究血清miR-590联合粪便钙卫蛋白(FC)对溃疡性结肠炎(UC)的诊断价值及与内镜下疾病活动度的相关性。方法 选择2021年1月至2023年2月滨州市人民医院消化内科收治的84例UC患者设为研究组,另选择同期在该院体检的56名健康志愿者设为对照组。分别采用实时荧光定量PCR法和ELISA法检测2组的血清miR-590和FC水平。采用Pearson相关性分析法探究血清miR-590与溃疡性结肠炎内镜下严重程度指数(UCEIS)的相关性,采用Spearman秩相关性分析法探究FC与UCEIS的相关性。采用ROC曲线分析血清miR-590联合FC对UC的诊断价值及与内镜下疾病活动度的相关性。结果 研究组的血清miR-590表达水平较对照组显著降低,FC水平较对照组显著升高,差异均有统计学意义(P均<0.05)。血清miR-590联合FC诊断UC的敏感度、特异度、曲线下面积(AUC)分别为95.48%、76.85%、0.914,两者联合的诊断效能均高于单一指标(P均<0.05)。与缓解期UC患者相比,活动期UC患者的血清miR-590表达水平较低,且血清miR-590表达水平与内镜下疾病活动度呈负相关(P<0.05)。与缓解期UC患者相比,活动期UC患者的FC水平较高,且FC水平与内镜下疾病活动度呈正相关(P<0.05)。UC患者的血清miR-590表达水平与UCEIS评分呈显著负相关(r=-0.791,P=0.000),FC水平与UCEIS评分呈显著正相关(r=0.884,P=0.000)。血清miR-590联合FC评估UC内镜下疾病活动度的敏感度、特异度、AUC分别为97.31%、78.42%、0.946,两者联合的评估效能均高于单一指标(P均<0.05)。结论 血清miR-590联合FC有助于提高UC诊断的敏感度,并可作为辅助指标评估内镜下疾病活动度,具有临床推广价值。

具有低噪声及高线性度的高性能MOCVD-SiN_(x)/AlN/GaN毫米波MIS-HEMTs

文章在超薄势垒AlN/GaN异质结构上采用金属有机化学气相沉积(MOCVD)原位生长SiN_(x)栅介质,成功制备了高性能的SiN_(x)/AlN/GaN金属-绝缘体-半导体高电子迁移率晶体管(MIS-HEMTs)。深能级瞬态谱(DLTS)技术测试SiN_(x)/AlN的界面信息,显示其缺陷能级深度为0.236 eV,俘获截面为3.06×10^(-19)cm^(-2),提取的界面态密度为10^(10)~10^(12)cm^(-2)eV^(-1),表明MOCVD原位生长的SiN_(x)可以有效降低界面态。同时器件表现出优越的直流、小信号和噪声性能。栅长为0.15μm的器件在2 V的栅极电压(Vgs)下具有2.2 A/mm的最大饱和输出电流,峰值跨导为506 mS/mm,最大电流截止频率(fT)和最大功率截止频率(fMAX)分别达到了65 GHz和123 GHz,40 GHz下的最小噪声系数(NFmin)为1.07 dB,增益为9.93 dB。Vds=6 V时对器件进行双音测试,器件的三阶交调输出功率(OIP3)为32.6 dBm,OIP3/Pdc达到11.2 dB。得益于高质量的SiN_(x)/AlN界面,SiN_(x)/AlN/GaN MISHEMT显示出了卓越的低噪声及高线性度,在毫米波领域具有一定的应用潜力。