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Performance-based seismic assessment of a historical masonry arch bridge: Effect of pulse-like excitations

《结构与土木工程前沿(英文)》   页码 855-869 doi: 10.1007/s11709-023-0972-z

摘要: Seismic analysis of historical masonry bridges is important for authorities in all countries hosting such cultural heritage assets. The masonry arch bridge investigated in this study was built during the Roman period and is on the island of Rhodes, in Greece. Fifteen seismic records were considered and categorized as far-field, pulse-like near-field, and non-pulse-like near-field. The earthquake excitations were scaled to a target spectrum, and nonlinear time-history analyses were performed in the transverse direction. The performance levels were introduced based on the pushover curve, and the post-earthquake damage state of the bridge was examined. According to the results, pulse-like near-field events are more damaging than non-pulse-like near-field ground motions. Additionally the bridge is more vulnerable to far-field excitations than near-field events. Furthermore, the structure will suffer extensive post-earthquake damage and must be retrofitted.

关键词: masonry arch bridges     seismic behavior     modal properties     pulse-like records     nonlinear time history analysis    

Extracting terms from clinical records of traditional Chinese medicine

null

《医学前沿(英文)》 2014年 第8卷 第3期   页码 347-351 doi: 10.1007/s11684-014-0361-z

摘要:

Health records of traditional Chinese medicine contain valuable clinical information which can be used for improvement of disease treatment and for medical research. In this paper, we present a practical iterative extraction method for extracting terms from the records. The method is based on a set of extraction rules, the Mesh, and the likelihood ratio technique, and achieved a precision rate of 88.18% and a recall rate of 94.21%.

关键词: term extraction     rule-based     likelihood ratio    

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    

光纤容量和传输距离打破纪录

Mitch Leslie

《工程(英文)》 2021年 第7卷 第2期   页码 139-140 doi: 10.1016/j.eng.2020.12.010

Improvement in growth yield of single-walled carbon nanotubes with narrow chirality distribution by pulse

Bin Xu, Toshiro Kaneko, Toshiaki Kato

《化学科学与工程前沿(英文)》 2019年 第13卷 第3期   页码 485-492 doi: 10.1007/s11705-019-1831-2

摘要: A pulse plasma chemical vapor deposition (CVD) technique was developed for improving the growth yield of single-walled carbon nanotubes (SWNTs) with a narrow chirality distribution. The growth yield of the SWNTs could be improved by repetitive short duration pulse plasma CVD, while maintaining the initial narrow chirality distribution. Detailed growth dynamics is discussed based on a systematic investigation by changing the pulse parameters. The growth of SWNTs with a narrow chirality distribution could be controlled by the difference in the nucleation time required using catalysts comprising relatively small or large particles as the key factor. The nucleation can be controlled by adjusting the pulse on/off time ratio and the total processing time.

关键词: single-walled carbon nanotubes     chirality-controlled synthesis     pulse plasma chemical vapor deposition    

苏通大桥短期观测流速在设计基准期内的应用

苏慧,龚维明,梁书亭

《中国工程科学》 2006年 第8卷 第7期   页码 42-46

摘要:

对缺乏长期流速资料的地区,给出了一种通过当地短期流速资料推算设计基准期参考流速的方法;通过分析苏通长江公路大桥水流速度观测的有关内容,采用实测的短期实际流速记录建立流速概率分布模型,按小样本推算极值的办法,得到大桥的设计基准期的基本流速并进行相关分析,确认计算结果的合理性,建立线性回归方程;为确保大桥在动力荷载作用下的安全应用及苏通大桥工程设计、施工提供可靠的技术指导。

关键词: 短期观测     设计基准期流速     相关分析     回归方程    

A modified pulse charging method for lithium-ion batteries by considering stress evolution, charging

Yanfei ZHAO, Bo LU, Yicheng SONG, Junqian ZHANG

《结构与土木工程前沿(英文)》 2019年 第13卷 第2期   页码 294-302 doi: 10.1007/s11709-018-0460-z

摘要: The stress evolution, total charging time and capacity utilization of pulse charging (PC) method are investigated in this paper. It is found that compared to the conventional constant current (CC) charging method, the PC method can accelerate the charging process but will inevitably cause an increase in stress and a decrease in capacity. The charging speed for PC method can be estimated by the mean current. By introducing stress control, a modified PC method called the PCCC method, which starts with a PC operation followed by a CC operation, is proposed. The PCCC method not only can accelerate charging process but also can avoid the stress raising and capacity loss occurring in the PC method. Furthermore, the optimal pulsed current density and switch time in the PCCC method is also discussed.

关键词: fast charging method     pulse charging     stress evolution     charging time     capacity utilization    

Characteristics and energy distribution of modulated multi-pulse injection modes based diesel HCCI combustion

LIU Bin, SU Wanhua, WANG Hui, HUANG Haozhong

《能源前沿(英文)》 2007年 第1卷 第4期   页码 420-427 doi: 10.1007/s11708-007-0061-7

摘要: Cycle fuel energy distribution and combustion characteristics of early in-cylinder diesel homogenous charge compression ignition (HCCI) combustion organized by modulated multi-pulse injection modes are studied by the engine test.

关键词: combustion     compression     homogenous     in-cylinder     modulated multi-pulse    

High frequency group pulse electrochemical machining

WU Gaoyang, ZHANG Zhijing, ZHANG Weimin, TANG Xinglun

《机械工程前沿(英文)》 2007年 第2卷 第3期   页码 293-296 doi: 10.1007/s11465-007-0051-5

摘要: In the process of machining ultrathin metal structure parts, the signal composition of high frequency group pulse, the influence of frequency to reverse current, and the design of the cathode in high frequency group pulse electrochemical machining (HGPECM) are discussed. The experiments on process were carried out. Results indicate that HGPECM can greatly improve the characteristics of the inter-electrode gap flow field, reduce electrode passivation, and obtain high machining quality. The machining quality is obviously improved by increasing the main pulse frequency. The dimensional accuracy reaches 30 40 ?m and the roughness attained is at 0.30 0.35 ?m. High frequency group pulse electrochemical machining can be successfully used in machining micro-parts.

关键词: HGPECM     process     machining quality     passivation     inter-electrode    

A driving pulse edge modulation technique and its complex programming logic devices implementation

Xiao CHEN,Dong-chang QU,Yong GUO,Guo-zhu CHEN

《信息与电子工程前沿(英文)》 2015年 第16卷 第12期   页码 1088-1098 doi: 10.1631/FITEE.1500111

摘要: With the continual increase in switching speed and rating of power semiconductors, the switching voltage spike becomes a serious problem. This paper describes a new technique of driving pulse edge modulation for insulated gate bipolar transistors (IGBTs). By modulating the density and width of the pulse trains, without regulating the hardware circuit, the slope of the gate driving voltage is controlled to change the switching speed. This technique is used in the driving circuit based on complex programmable logic devices (CPLDs), and the switching voltage spike of IGBTs can be restrained through software, which is easier and more flexible to adjust. Experimental results demonstrate the effectiveness and practicability of the proposed method.

关键词: Driving pulse edge modulation     Switching voltage spike     Complex programmable logic device (CPLD)     Active gate drive    

基于脉冲阵列图像传感器的高速高亮度目标检测 Research Article

张培文1,2,徐江涛1,2,聂华峰1,2,高志远1,2,聂凯明1,2

《信息与电子工程前沿(英文)》 2022年 第23卷 第1期   页码 113-122 doi: 10.1631/FITEE.2000407

摘要: 提出一种基于脉冲阵列图像传感器(PAIS)的高速高亮目标光流提取方法。PAIS是将光信号转换成一系列脉冲间隔的仿视网膜图像传感器。通过累积连续脉冲直接从脉冲数据流中获得光流,当目标相对于背景亮度较大时,触发点可过滤冗余数据。该方法充分利用PAIS对高亮度目标快速响应特性。将该方法用于不同背景亮度高速转盘的光流提取,在传感器模型和实际拍摄数据中进行实验。在2×104帧/秒的采样条件下拍摄转速为1000转/分的高速转盘,可以滤除90%以上冗余点。实验结果表明,基于脉冲数据的光流提取算法可在无需重构灰度图像基础上有效提取高亮目标光流信息。

关键词: 光流;仿视网膜图像传感器;脉冲触发;高速目标;视觉处理    

Distinct immune escape and microenvironment between RG-like and pri-OPC-like glioma revealed by single-cell

《医学前沿(英文)》 doi: 10.1007/s11684-023-1017-7

摘要: The association of neurogenesis and gliogenesis with glioma remains unclear. By conducting single-cell RNA-seq analyses on 26 gliomas, we reported their classification into primitive oligodendrocyte precursor cell (pri-OPC)-like and radial glia (RG)-like tumors and validated it in a public cohort and TCGA glioma. The RG-like tumors exhibited wild-type isocitrate dehydrogenase and tended to carry EGFR mutations, and the pri-OPC-like ones were prone to carrying TP53 mutations. Tumor subclones only in pri-OPC-like tumors showed substantially down-regulated MHC-I genes, suggesting their distinct immune evasion programs. Furthermore, the two subgroups appeared to extensively modulate glioma-infiltrating lymphocytes in distinct manners. Some specific genes not expressed in normal immune cells were found in glioma-infiltrating lymphocytes. For example, glial/glioma stem cell markers OLIG1/PTPRZ1 and B cell-specific receptors IGLC2/IGKC were expressed in pri-OPC-like and RG-like glioma-infiltrating lymphocytes, respectively. Their expression was positively correlated with those of immune checkpoint genes (e.g., LGALS3) and poor survivals as validated by the increased expression of LGALS3 upon IGKC overexpression in Jurkat cells. This finding indicated a potential inhibitory role in tumor-infiltrating lymphocytes and could provide a new way of cancer immune evasion.

关键词: single-cell RNA-seq     glioma     radial glia     primitive oligodendrocyte precursor cell     immune escape    

一种使用交互分析武器系统对作战场景基于过程建模的方法 Research

Dongsu JEONG, Dohyun KIM, Yoonho SEO

《信息与电子工程前沿(英文)》 2021年 第22卷 第3期   页码 287-436 doi: 10.1631/FITEE.1900649

摘要: 随着技术进步,武器系统开发变得复杂而昂贵。在概念设计阶段使用建模和仿真(M&S)技术可有效减少武器的开发时间和成本。为降低与武器开发相关的复杂性,减少反复试验,一种方法是使用M&S技术开发作战方案,以审查分配给新武器的功能。尽管M&S技术适用于该方法,由于战斗场景建模固有的动态特性(考虑到不同武器实体之间的相互关系),难以分析武器的运行效率。为审查具备这些特征的武器功能,本文开发了一种基于过程的建模(PBM)方法来对战斗场景中武器之间的相互作用建模。该方法包括以下3个步骤:(1)通过将武器和武器功能转换为相应的组件来构建虚拟模型;(2)依据战斗情景生成战斗过程,该战斗过程是使用推理规则从被研究的武器之间的相互关系中得出的;(3)通过将战斗过程与虚拟模型相结合,开发一种基于过程的模型来描述武器功能。然后,实现了基于该方法的PBM系统。在该系统上开展案例研究,结果表明,在从各种作战场景中得出基于过程的模型、使用该模型分析武器功能以及在概念设计阶段减少武器开发问题方面,该系统均体现作用。

关键词: 武器系统;基于过程的建模(PBM);作战场景;交互分析;元模型;Petri网    

Energy distribution between liquid hydrogen and liquid oxygen temperatures in a Stirling/pulse tube refrigerator

《能源前沿(英文)》 2023年 第17卷 第4期   页码 516-526 doi: 10.1007/s11708-022-0844-6

摘要: A two-stage gas-coupled Stirling/pulse tube refrigerator (SPR), whose first and second stages respectively involve Stirling and pulse tube refrigeration cycles, is a very promising spaceborne refrigerator. The SPR has many advantages, such as a compact structure, high reliability, and high performance, and is expected to become an essential refrigerator for space applications. In research regarding gas-coupled regenerative refrigerator, the energy flow distribution between the two stages, and optimal phase difference between the pressure wave and volume flow, are two critical parameters that could widely influence refrigerator performance. The effects of displacer displacement on the pressure wave, phase difference, acoustic power distribution, and inter-stage cooling capacity shift of the SPR have been investigated experimentally. Notably, to obtain the maximum first-stage cooling capacity, an inflection point in displacement exists. When the displacer displacement is larger than the inflection point, the cooling capacity could be distributed between the first and second stages. In the present study, an SPR was designed and manufactured to work between the liquid hydrogen and liquid oxygen temperatures, which can be used to cool small-scale zero boil-off systems and space detectors. Under appropriate displacer displacement, the SPR can reach a no-load cooling temperature of 15.4 K and obtain 2.6 W cooling capacity at 70 K plus 0.1 W cooling capacity at 20 K with 160 W compressor input electric power.

关键词: Stirling/pulse tube refrigerator     displacer displacement     space application     phase shift     energy distribution    

Self-sacrificial templating synthesis of flower-like nickel phyllosilicates and its application as high-performance

《化学科学与工程前沿(英文)》 2022年 第16卷 第4期   页码 484-497 doi: 10.1007/s11705-021-2074-6

摘要: The nanocomposites of flower-like nickel phyllosilicate particles incorporated into epoxy resin were fabricated via an in-situ mixing process. The flower-like nickel phyllosilicate particles were firstly synthesized using a mild self-sacrificial templating method, and the morphology and lamellar structure were examined carefully. Several properties of mechanical, thermal and tribological responses of epoxy nanocomposites were performed. It was demonstrated that adequate flower-like nickel phyllosilicate particles dispersed well in the matrix, and the nanocomposites displayed enhanced tensile strength and elastic modulus but decreased elongation at break as expected. In addition, friction coefficient and wear rate were increased first and then decreased along with the particle content, and showed the lowest values at a mass fraction of 5%. Nevertheless, the incorporated flower-like nickel phyllosilicate particles resulted in the continuously increasing thermal stability of epoxy resin (EP) nanocomposites. This study revealed the giant potential of flower-like particles in preparing high-quality EP nanocomposites.

关键词: nickel phyllosilicate     flow-like structure     mechanical property     thermal stability     tribological performance    

标题 作者 时间 类型 操作

Performance-based seismic assessment of a historical masonry arch bridge: Effect of pulse-like excitations

期刊论文

Extracting terms from clinical records of traditional Chinese medicine

null

期刊论文

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

null

期刊论文

光纤容量和传输距离打破纪录

Mitch Leslie

期刊论文

Improvement in growth yield of single-walled carbon nanotubes with narrow chirality distribution by pulse

Bin Xu, Toshiro Kaneko, Toshiaki Kato

期刊论文

苏通大桥短期观测流速在设计基准期内的应用

苏慧,龚维明,梁书亭

期刊论文

A modified pulse charging method for lithium-ion batteries by considering stress evolution, charging

Yanfei ZHAO, Bo LU, Yicheng SONG, Junqian ZHANG

期刊论文

Characteristics and energy distribution of modulated multi-pulse injection modes based diesel HCCI combustion

LIU Bin, SU Wanhua, WANG Hui, HUANG Haozhong

期刊论文

High frequency group pulse electrochemical machining

WU Gaoyang, ZHANG Zhijing, ZHANG Weimin, TANG Xinglun

期刊论文

A driving pulse edge modulation technique and its complex programming logic devices implementation

Xiao CHEN,Dong-chang QU,Yong GUO,Guo-zhu CHEN

期刊论文

基于脉冲阵列图像传感器的高速高亮度目标检测

张培文1,2,徐江涛1,2,聂华峰1,2,高志远1,2,聂凯明1,2

期刊论文

Distinct immune escape and microenvironment between RG-like and pri-OPC-like glioma revealed by single-cell

期刊论文

一种使用交互分析武器系统对作战场景基于过程建模的方法

Dongsu JEONG, Dohyun KIM, Yoonho SEO

期刊论文

Energy distribution between liquid hydrogen and liquid oxygen temperatures in a Stirling/pulse tube refrigerator

期刊论文

Self-sacrificial templating synthesis of flower-like nickel phyllosilicates and its application as high-performance

期刊论文