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2022 4

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3D打印 1

GC-Q-TOFMS 1

HRT 波模型的实用性 1

LC-Q-TOFMS 1

“PS -100”HRT 波接收网站 1

“黑箱”与HRT 波预测模型 1

二肽基肽酶4 1

公共卫生事件，应急管理，疫情防控，精准感知，信息技术赋能，一体化 1

农药残留 1

力矩波动 1

垂直双扩散MOS场效应晶体管 1

复杂严重髋臼骨缺损 1

大惯量 1

安全设计 1

数据流；多维序列；异常检测；概念漂移；特征选择 1

方法重命名；代码重构；深度学习；卷积神经网络 1

最优传输；Monge-Ampère方程；自适应采样 1

标志物来源追溯 1

死区 1

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Smart model for accurate estimation of solar radiation

Lazhar ACHOUR, Malek BOUHARKAT, Ouarda ASSAS, Omar BEHAR

《能源前沿（英文）》 2020年第14卷第2期页码 383-399 doi: 10.1007/s11708-017-0505-3

摘要： Prediction of solar radiation has drawn increasing attention in the recent years. This is because of the lack of solar radiation measurement stations. In the present work, 14 solar radiation models have been used to assess monthly global solar radiation on a horizontal surface as function of three parameters: extraterrestrial solar irradiance ( ), duration sunshine ( ) and daylight hours ( ). Since it has been observed that each model is adequate for some months of the year, one model cannot be used for the prediction of the whole year. Therefore, a smart hybrid system is proposed which selects, based on the intelligent rules, the most suitable prediction model of the 14 models listed in this study. For the test and evaluation of the proposed models, Tamanrasset city, which is located in the south of Algeria, is selected for this study. The meteorological data sets of five years (2000–2004) have been collected from the Algerian National Office of Meteorology (NOM), and two spatial databases. The results indicate that the new hybrid model is capable of predicting the monthly global solar radiation, which offers an excellent measuring accuracy of values ranging from 93% to 97% in this location.

关键词： global solar radiation statistical indicator hybrid model spatial database correlation coefficients

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Improving Internationally Core Competences Based on the Capabilities of Precise and Accurate Project

Zhen-you Li,Ji-shan He,Meng-jun Wang

《工程管理前沿（英文）》 2016年第3卷第3期页码 231-238 doi: 10.15302/J-FEM-2016032

摘要： Modern international project management has entered the phase of precise and accurate project management after the global financial crisis broke out at the beginning of the 21 century. However, its development has faced new challenges since there has been lack of explicitly unanimous definition for the capability dimensions of precise and accurate project management, as well as the models and their process control parameters. The required core capabilities based on the precise and accurate project management for various rings are involved in the project life cycle, namely, the required internationally core competences and their components for the phases of project strategic planning and decision making in the early project phase, as well as the value engineering, and the project supervision and controls during the execution phase. Through studying the effects of the internationally core competences based on precise and accurate project management capabilities for the success and excellence of projects and configuring such models, the goal is to help the main contractors continuously obtain project success and excellence, thus improve its internationally core competences with continuous project success and excellence.

关键词： precise and accurate project management project strategic planning decision-making project supervision and controls project execution value engineering

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Esophageal pulse oximetry is more accurate and detects hypoxemia earlier than conventional pulse oximetry

null

《医学前沿（英文）》 2012年第6卷第4期页码 406-410 doi: 10.1007/s11684-012-0217-3

摘要：

The esophagus is perfused directly by prominent arteries and may provide a more consistent tissue source for pulse oximetry. The goal of this study was to evaluate the sensitivity and accuracy of an esophageal pulse oximetry probe on patients during controlled hypoxemia in comparison to measurements obtained with conventional pulse oximetry (SpulseO₂). Forty-five ASA I–II adult patients were included in this prospective observational study. Nellcor digital oximetric probes were placed on finger tips for SpulseO₂ before anesthesia. After tracheal intubation, an esophageal probe was placed in the lower segment of the esophagus for esophageal oximetric monitoring (SoesO₂). All patients were disconnected from the breathing circuit to establish a controlled hypoxemia, and were re-connected to the breathing circuit and ventilated with 100% oxygen immediately when SoesO₂ dropped to 90%. Matched SoesO₂ and SpulseO₂ readings were recorded when SoesO₂measurements were at 100%, 95%, 90% and the lowest reading. The time for SoesO₂ and SpulseO₂ to drop from 100% to 95%, 90% and return to 100% was recorded. Oxygen saturation from arterial blood samples (SartO₂) was also measured at each time point respectively. The linear correlation coefficient of the regression analysis between SartO₂ and SoesO₂ was 0.954. The mean±2SD of the difference was 0.3%±4.3% for SoesO₂vs. SartO₂ and 6.8%±5.6% for SpulseO₂vs. SartO₂ (P<0.001). The 95% confidence interval for the absolute difference between SoesO₂ and SartO₂ was 0.3% to 0.7% and 6.2% to 7.4% between SpulseO₂ and SartO₂. The time to reach 90% saturation measured with SoesO₂ was approximately 94 seconds earlier than the SpulseO₂ (P<0.001). In conclusion, SoesO₂ is more accurate and enables earlier detection of hypoxemia when compared to conventional pulse oximetry during hypoxemia for patients undergoing general anesthesia.

关键词： esophageal pulse oximetry conventional pulse oximetry hypoxemia

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A fast and accurate dynamic relaxation scheme

Mohammad REZAIEE-PAJAND, Mohammad MOHAMMADI-KHATAMI

《结构与土木工程前沿（英文）》 2019年第13卷第1期页码 176-189 doi: 10.1007/s11709-018-0486-2

摘要： Dynamic relaxation method (DRM) is one of the suitable numerical procedures for nonlinear structural analysis. Adding the fictitious inertia and damping forces to the static equation, and turning it to the dynamic system, are the basis of this technique. Proper selection of the DRM artificial factors leads to the better convergence rate and efficient solutions. This study aims to increase the numerical stability, and to decrease the analysis time. To fulfil this objective, the reduction rate of analysis error for consecutive iterations is minimized. Based on this formulation, a new time step is found for the viscous dynamic relaxation. After combining this novel relationship with the other DRM factors, various geometrical nonlinear structures, such as, trusses, frames and shells are analyzed. The obtained results verify the efficiency of authors’ scheme.

关键词： viscous dynamic relaxation time step displacement error geometric nonlinear analysis

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An Ultracompact Spoof Surface Plasmon Sensing System for Adaptive and Accurate Detection of Gas Using

Xuanru Zhang,Jia Wen Zhu,Tie Jun Cui,

《工程（英文）》 doi: 10.1016/j.eng.2023.05.013

摘要： Resonantly enhanced dielectric sensing has superior sensitivity and accuracy because the signal is measured from relative resonance shifts that are immune to signal fluctuations. For applications in the Internet of Things (IoT), accurate detection of resonance frequency shifts using a compact circuit is in high demand. We proposed an ultracompact integrated sensing system that merges a spoof surface plasmon resonance sensor with signal detection, processing, and wireless communication. A software-defined scheme was developed to track the resonance shift, which minimized the hardware circuit and made the detection adaptive to the target resonance. A microwave spoof surface plasmon resonator was designed to enhance sensitivity and resonance intensity. The integrated sensing system was constructed on a printed circuit board with dimensions of 1.8 cm × 1.2 cm and connected to a smartphone wirelessly through Bluetooth, working in both frequency scanning mode and resonance tracking mode and achieving a signal-to-noise ratio of 69 dB in acetone vapor sensing. This study provides an ultracompact, accurate, adaptive, sensitive, and wireless solution for resonant sensors in the IoT.

关键词： Spoof surface plasmons Internet of Things Integrated sensing Resonance tracking Microwave sensing

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An adaptive data-driven method for accurate prediction of remaining useful life of rolling bearings

Yanfeng PENG, Junsheng CHENG, Yanfei LIU, Xuejun LI, Zhihua PENG

《机械工程前沿（英文）》 2018年第13卷第2期页码 301-310 doi: 10.1007/s11465-017-0449-7

摘要：

A novel data-driven method based on Gaussian mixture model (GMM) and distance evaluation technique (DET) is proposed to predict the remaining useful life (RUL) of rolling bearings. The data sets are clustered by GMM to divide all data sets into several health states adaptively and reasonably. The number of clusters is determined by the minimum description length principle. Thus, either the health state of the data sets or the number of the states is obtained automatically. Meanwhile, the abnormal data sets can be recognized during the clustering process and removed from the training data sets. After obtaining the health states, appropriate features are selected by DET for increasing the classification and prediction accuracy. In the prediction process, each vibration signal is decomposed into several components by empirical mode decomposition. Some common statistical parameters of the components are calculated first and then the features are clustered using GMM to divide the data sets into several health states and remove the abnormal data sets. Thereafter, appropriate statistical parameters of the generated components are selected using DET. Finally, least squares support vector machine is utilized to predict the RUL of rolling bearings. Experimental results indicate that the proposed method reliably predicts the RUL of rolling bearings.

关键词： Gaussian mixture model distance evaluation technique health state remaining useful life rolling bearing

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Seismic performance of viaducts with probabilistic method

ZHU Xi, WANG Jianmin

《结构与土木工程前沿（英文）》 2007年第1卷第3期页码 267-273 doi: 10.1007/s11709-007-0034-y

摘要： Due to the uncertainty of both ground motions and structural capacity, it is necessary to consider the seismic performance of viaduct structures using the probabilistic method. The risk is quantified by a procedure on the basis of a numerical determination of the fragility curves. A group of ground motions, Large Magnitude-Short Distance Bin (LMSR-N), selected specially due to its response spectra, is accorded well with the corresponding spectra of the Chinese code for seismic design. The characteristic values of the curvature ductility factors for the serviceability and the damage control limit states are obtained, and two equations for estimating the characteristic values of the curvature ductility factors are developed through regression analysis. Then, the serviceability and damage control limit states were proposed. Three damage states were constituted according the results of the experiment by Pacific Earthquake Engineering Research (PEER) Center. The analytical fragility curves were obtained specifically, using both Capacity Spectrum Method (CSM) (non-linear static) analysis and Ineremental Dynamic Method (IDM) (non-linear dynamic) analysis, respectively, in this paper. The structural fragility curves developed by CSM method can help make the structural analysis simple and quick, avoiding the implementation of the dynamic response history analysis (RHA). Although the dynamic RHA requires a lot of complicated analysis for the structure, the results from RHA are reliable and accurate. Fragility curves are powerful tools for use in performance-based seismic bridge design.

关键词： uncertainty Earthquake Engineering regression analysis accurate fragility

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Damage identification of a large-span concrete cable-stayed bridge based on genetic algorithm

ZHU Jinsong, XIAO Rucheng

《结构与土木工程前沿（英文）》 2007年第1卷第2期页码 170-175 doi: 10.1007/s11709-007-0018-y

摘要： The global stability of a structure, the stiffness of its main girder and concrete tower, and the variation of the forces of its stay cables are key issues to the safety assessment of an in-service cable-stayed bridge. The efficiency and rationality of local elaborate non-damage-identification could be enhanced by the primary damage identification of cable-stayed bridges on the basis of periodic detection of the cable force and strain monitor in key sections of the main girder. The genetic algorithms of damage identification for cable-stayed bridges were investigated in this paper on the basis of the monitor data of the cable force and strain in a key section of the main girder. A damage detection program for complex civil structure was generated to implement the identification of damage location and extent. The deterioration of the structure was calculated according to the variation of monitor data. It is demonstrated that the results of damage identification from the parametric finite element method are accurate. The method had been verified using a long-span concrete cable-stayed bridge in Ningbo, which has been in use for the past four years.

关键词： accurate primary global stability complex identification

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Application of an efficient stochastic calculation method on the seismic analysis of an isolated structure

Wei GUO, Zhiwu YU

《结构与土木工程前沿（英文）》 2012年第6卷第4期页码 379-384 doi: 10.1007/s11709-012-0180-8

摘要： An isolated structure often possesses distinct non-proportional damping characteristics. However, traditional seismic calculation theory and methods are derived based on the assumption that damping is proportional. Based on this drawback, a new, more efficient stochastic calculation method, an improvement on the pseudo-excitation method, is introduced. This method is then applied to the seismic analysis of an isolated structure. By comparing it with the forced decoupling, matrix inversion and iteration methods, it is shown that the presented method can produce accurate results while increasing the efficiency of the stochastic analysis. Moreover, the calculation process of the seismic response of an isolated structure is convergent. Based on the results of the example presented in this paper, the given method is applicable to the seismic analysis of an isolated structure and can be utilized in practice.

关键词： isolated structure stochastic response non-proportional damping efficient accurate pseudo-excitation method

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Optimization model for rotor blades of horizontal axis wind turbines

LIU Xiong, CHEN Yan, YE Zhiquan

《机械工程前沿（英文）》 2007年第2卷第4期页码 483-488 doi: 10.1007/s11465-007-0084-9

摘要： This paper presents an optimization model for rotor blades of horizontal axis wind turbines. The model refers to the wind speed distribution function on the specific wind site, with an objective to satisfy the maximum annual energy output. To speed up the search process and guarantee a global optimal result, the extended compact genetic algorithm (ECGA) is used to carry out the search process. Compared with the simple genetic algorithm, ECGA runs much faster and can get more accurate results with a much smaller population size and fewer function evaluations. Using the developed optimization program, blades of a 1.3 MW stall-regulated wind turbine are designed. Compared with the existing blades, the designed blades have obviously better aerodynamic performance.

关键词： population extended algorithm developed optimization accurate

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Accurate quantification of 3′-terminal 2′-O-methylated small RNAs by utilizing oxidative deep sequencing

《医学前沿（英文）》 2022年第16卷第2期页码 240-250 doi: 10.1007/s11684-021-0909-7

摘要： The continuing discoveries of novel classes of RNA modifications in various organisms have raised the need for improving sensitive, convenient, and reliable methods for quantifying RNA modifications. In particular, a subset of small RNAs, including microRNAs (miRNAs) and Piwi-interacting RNAs (piRNAs), are modified at their 3′-terminal nucleotides via 2′-O-methylation. However, quantifying the levels of these small RNAs is difficult because 2′-O-methylation at the RNA 3′-terminus inhibits the activity of polyadenylate polymerase and T4 RNA ligase. These two enzymes are indispensable for RNA labeling or ligation in conventional miRNA quantification assays. In this study, we profiled 3′-terminal 2′-O-methyl plant miRNAs in the livers of rice-fed mice by oxidative deep sequencing and detected increasing amounts of plant miRNAs with prolonged oxidation treatment. We further compared the efficiency of stem-loop and poly(A)-tailed RT-qPCR in quantifying plant miRNAs in animal tissues and identified stem-loop RT-qPCR as the only suitable approach. Likewise, stem-loop RT-qPCR was superior to poly(A)-tailed RT-qPCR in quantifying 3′-terminal 2′-O-methyl piRNAs in human seminal plasma. In summary, this study established a standard procedure for quantifying the levels of 3′-terminal 2′-O-methyl miRNAs in plants and piRNAs. Accurate measurement of the 3′-terminal 2′-O-methylation of small RNAs has profound implications for understanding their pathophysiologic roles in biological systems.

关键词： small RNAs 2′-O-methylation sequencing RT-qPCR

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3D打印髋关节假体为复杂髋臼骨缺损翻修全髋关节置换术提供精准重建、稳定固定和功能恢复 Article

郝永强, 王磊, 姜闻博, 武文, 艾松涛, 沈路, 赵双, 戴尅戎

《工程（英文）》 2020年第6卷第11期页码 1285-1290 doi: 10.1016/j.eng.2020.04.013

摘要：

复杂而严重的髋臼骨缺损是人工髋关节置换术重建过程中最主要的挑战和难点。本研究旨在探讨3D打印技术在重建这种复杂髋臼骨缺损中的优势。我们回顾性分析了3例使用3D打印技术治疗的复杂髋臼骨缺损患者的预后，其中一例患者涉及双侧缺损重建。这些髋臼骨缺损的共同特点为常规方法难以重建。因此，在本研究中，我们首先结合了医学影像学分析、计算机软件模拟和重建（如MIMICS软件和西门子NX软件）及实际手术经验对缺损体积、假体重建稳定性和假体安装精度进行预测和评估，Harris髋关节评分被用来评估肢体功能。我们的结果表明3D打印假体可以精准重建骨缺损，并获得良好的假体稳定性，并且Harris髋关节评分显示3位患者肢体功能得到较好的恢复。总而言之，3D打印技术在人工髋关节翻修术中应对复杂且程度较为严重的骨缺损具有非常好的治疗效果，最终患者获得满意的预后。

关键词： 3D打印髋关节翻修复杂严重髋臼骨缺损精准重建

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高压VDMOS的一种高精度静态物理模型

鲍嘉明,孙伟锋,赵野,陆生礼

《中国工程科学》 2008年第10卷第2期页码 72-78

摘要：

提出了高压VDMOS的一种高精度静态物理模型(HASPM)。在该模型中，基于更为合理的假设而使得用解析方法求得了双扩散沟道区中的电场和电压；通过深入研究VDMOS 内部的物理特性，给出了一个关于漂移区电场的微分方程，并在整个漂移区都用解析方法求解了该微分方程，由此求得了漂移区的电压降。计算结果表明，该模型在漏端电流接近饱和处的稳定性有较大提高，具有较高的计算精度，特别是在栅电压与漏电压都比较大的情况下，其计算精度有较大程度的提高。

关键词：垂直双扩散MOS场效应晶体管静态物理模型解析方法

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海洋二号卫星大惯量旋转部件干扰力矩抑制技术

周勇,李正军,马超,王小宁

《中国工程科学》 2014年第16卷第3期页码 43-49

摘要：

海洋二号（HY-2A）卫星要求微波散射计和微波辐射计实现扫描过程中所产生的力矩波动不能影响卫星姿态稳定度。这两个载荷使用永磁同步电动机矢量控制，对负载直接驱动；通过电机本体采用齿槽转矩优化设计、采用固定角度计时法消除量化误差、相电流测量误差控制、逆变器死区补偿等措施，抑制转矩波动。通过电机本体和控制策略进行联合精确模型仿真，分析了系统的转矩波动。由在轨遥测数据分析可得，实现了大惯量旋转部件的精确控制。

关键词：大惯量力矩波动量化误差死区精确模型

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Constitutive Model for an FCC Single-Crystal Material

DING Zhi-ping, LIU Yi-lun, YIN Ze-yong, YANG Zhi-guo, CHENG Xiao-ming

《机械工程前沿（英文）》 2006年第1卷第1期页码 40-47 doi: 10.1007/s11465-005-0012-9

摘要：

Taking into account the effects that the components of tension stresses couple with components of torsion stresses when off-axis loads are applied to orthotropic materials, Hill s yield criterion for plastically orthotropic solids is modified by adding an invariant that is composed of the product item of quadratic components of the deviatoric stress tensor, and a new yield criterion is put forward in terms of the characteristics of the face-centered cubic (FCC) single-crystal material. The correlation of prediction and experiments is very good, and the new criterion is used to predict the yield stresses of an internal single-crystal, Nickel-based superalloy, DD3, which is more accurate than that of Hill s at 760?C. Equivalent stress and strain that adapt to the new criterion are defined. Thinking of the yield function as a plastic potential function from the associated flow rule, the elastic plastic constitutive model for the FCC single-crystal material is constructed, and the corresponding elastic plastic matrix is educed. The new yield criterion and its equivalent stress and strain will be reduced to Von Mises yield criterion and corresponding equivalent stress and strain for isotropic materials.

关键词： orthotropic Thinking accurate prediction corresponding