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Applications of traditional pump design theory to artificial heart and CFD simulation

WANG Yingpeng, SONG Xinwei, YING Chuntong

《能源前沿（英文）》 2008年 第2卷 第4期   页码 504-507 doi: 10.1007/s11708-008-0059-5

摘要： A novel heart pump model was obtained by improving the traditional axial pump design theory with the consideration of working and hydraulic situations for artificial hearts. The pump head range and the velocity triangle were introduced and an iterative approach was utilized for the initial model. Moreover, computational fluid dynamics (CFD) simulations were performed to determine relevant model parameters. The results show that this procedure can be used for designing a series of high-efficiency artificial heart pumps.

关键词： computational     high-efficiency artificial     iterative approach     artificial     traditional    

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Wavelet-based iterative data enhancement for implementation in purification of modal frequency for extremely

Hassan YOUSEFI, Alireza TAGHAVI KANI, Iradj MAHMOUDZADEH KANI, Soheil MOHAMMADI

《结构与土木工程前沿（英文）》 2020年 第14卷 第2期   页码 446-472 doi: 10.1007/s11709-019-0605-8

摘要： The main purpose of the present study is to enhance high-level noisy data by a wavelet-based iterative filtering algorithm for identification of natural frequencies during ambient wind vibrational tests on a petrochemical process tower. Most of denoising methods fail to filter such noise properly. Both the signal-to-noise ratio and the peak signal-to-noise ratio are small. Multiresolution-based one-step and variational-based filtering methods fail to denoise properly with thresholds obtained by theoretical or empirical method. Due to the fact that it is impossible to completely denoise such high-level noisy data, the enhancing approach is used to improve the data quality, which is the main novelty from the application point of view here. For this iterative method, a simple computational approach is proposed to estimate the dynamic threshold values. Hence, different thresholds can be obtained for different recorded signals in one ambient test. This is in contrast to commonly used approaches recommending one global threshold estimated mainly by an empirical method. After the enhancements, modal frequencies are directly detected by the cross wavelet transform (XWT), the spectral power density and autocorrelation of wavelet coefficients. Estimated frequencies are then compared with those of an undamaged-model, simulated by the finite element method.

关键词： ambient vibration test     high level noise     iterative signal enhancement     wavelet     cross and autocorrelation of wavelets    

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Iterative finite element model of nonlinear viscoplastic analyses for blended granular porous media

WU Yuching, ZHU Cimian

《结构与土木工程前沿（英文）》 2007年 第1卷 第4期   页码 464-473 doi: 10.1007/s11709-007-0063-6

摘要： The iterative finite element model, in which an element is used to represent a single particle, is generated to analyze the global behavior of multiple-material aggregates of materially nonlinear viscoplastic particles. The genera

关键词： nonlinear viscoplastic     iterative     behavior     multiple-material    

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Improving prodeoxyviolacein production via multiplex SCRaMbLE iterative cycles

Juan Wang, Bin Jia, Zexiong Xie, Yunxiang Li, Yingjin Yuan

《化学科学与工程前沿（英文）》 2018年 第12卷 第4期   页码 806-814 doi: 10.1007/s11705-018-1739-2

摘要：

The synthetic chromosome rearrangement and modification by loxP-mediated evolution (SCRaMbLE) system has been used to improve prodeoxyviolacein (PDV) production in haploid yeast containing chromosome synV. To rapidly and continuously generate genome diversification with the desired phenotype, the multiplex SCRaMbLE iterative cycle strategy has been developed for the screening of high PDV production strains. Whole-genome sequencing analysis reveals large duplications, deletions, and even the whole genome duplications. The deletion of YER151C is proved to be responsible for the increase. This study demonstrates that artificial DNA rearrangement can be used to accelerate microbial evolution and the production of biobased chemicals.

关键词： synthetic biology     genome rearrangement     prodeoxyviolacein     SCRaMbLE     Saccharomyces cerevisiae    

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A fast compound direct iterative algorithm for solving transient line contact elastohydrodynamic lubrication

null

《机械工程前沿（英文）》 2014年 第9卷 第2期   页码 156-167 doi: 10.1007/s11465-014-0297-7

摘要：

A fast compound direct iterative algorithm for solving transient line contact elastohydrodynamic lubrication (EHL) problems is presented. First, by introducing a special matrix splitting iteration method into the traditional compound direct iterative method, the full matrices for the linear systems of equations are transformed into sparse banded ones with any half-bandwidth; then, an extended Thomas method which can solve banded linear systems with any half-bandwidth is derived to accelerate the computing speed. Through the above two steps, the computational complexity of each iteration is reduced approximately from O(N3/3) to O(β2N), where N is the total number of nodes, and β is the half-bandwidth. Two kinds of numerical results of transient EHL line contact problems under sinusoidal excitation or pure normal approach process are obtained. The results demonstrate that the new algorithm increases computing speed several times more than the traditional compound direct iterative method with the same numerical precision. Also the results show that the new algorithm can get the best computing speed and robustness when the ratio, half-bandwidth to total number of nodes, is about 7.5%–10.0% in moderate load cases.

关键词： elastohydrodynamic lubrication     transient     line contact     matrix splitting iteration method     the Thomas method    

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模糊迭代学习方法及高层建筑结构地震响应控制的数值模拟

汪权,王建国,张鸣祥

《中国工程科学》 2011年 第13卷 第4期   页码 81-86

摘要：

结合自校正控制、模糊逻辑和迭代学习控制的基本思想，提出采用自整定模糊控制确定迭代学习律的方法，提高了迭代学习控制的鲁棒性。选取建筑结构振动控制Benchmark第二阶段的地震作用Benchmark模型作为研究对象，进行模糊迭代学习控制地震响应仿真计算，结果表明该方法能够对Benchmark模型的地震响应进行有效控制，而且具有学习控制律简单实用、跟踪精度高、鲁棒性强等优点。

关键词： 高层建筑     地震响应     迭代学习控制     模糊控制    

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针对主动磁悬浮轴承干扰抑制的一类结合迭代学习控制与干扰观测器的解决方法 None

Ze-zhi TANG, Yuan-jin YU, Zhen-hong LI, Zheng-tao DING

《信息与电子工程前沿（英文）》 2019年 第20卷 第1期   页码 131-140 doi: 10.1631/FITEE.1800558

摘要： 针对主动磁悬浮轴承系统，传统迭代学习控制可实现高精度轨迹跟踪，但系统扰动必须限定为不随迭代变化。基于目前方法，提出一种抑制主动磁悬浮轴承系统中随迭代变化的不匹配扰动方法。在该方案中，结合经典迭代学习控制和普适性扩张观测器，在使用输出反馈信息情况下，可在每次迭代过程中估计并抑制外界变化干扰。分析证明了整个闭环系统的收敛性，同时，仿真结果表明，相比传统迭代学习控制，该控制方法轨迹跟踪性能更加优良。

关键词： 主动磁悬浮轴承；迭代学习控制；干扰观测器    

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适于低成本嵌入式硬件的2R-1C模型非迭代参数估计 Article

Mitar SIMIĆ, Zdenka BABIĆ, Vladimir RISOJEVIĆ, Goran M. STOJANOVIĆ

《信息与电子工程前沿（英文）》 2020年 第21卷 第3期   页码 476-490 doi: 10.1631/FITEE.1900112

摘要： 2R-1C模型的参数估计常运用需要高性能处理单元的迭代方法，从而激励我们研究更省时且更节能的参数估计方法。这些低复杂度的算法将更适于便携式微机设备的运行。本文提出二次插值非迭代参数估计方法（QINIPE）；该方法基于测量阻抗虚部的二次插值，能够更精确地估计特征频率。运用一组封闭表达式从测量阻抗的实部和虚部计算2R-1C模型的参数。对仿真和测量获得的模型阻抗数据作对比分析；结果表明，相较于我们早前提出的非迭代参数估计方法（NIPE），QINIPE能减少80%测量点，且所有估计参数的相对估计误差低于1%。两种非迭代方法均基于一个微机设备实施；检测了估计精度、RAM、闪存使用以及运行时间。实验结果表明，相较于NIPE，QINIPE轻微增加了0.576 ms运行时间（约6.7%），且需要多24%（1.2 KB）闪存及多2.4%（32字节）RAM。然而，QINIPE的阻抗均方根误差分别降低至NIPE对应的42.8%（实部）和64.5%（虚部）。此外，比较了QINIPE和复杂非线性最小二乘法（CNLS）对2R-1C模型参数的估计。结果表明，虽然QINIPE估计精度稍低于CNLS，其依然适合许多实际应用，且运行时间降至原来的1/45至1/30。

关键词： 2R-1C模型；嵌入式系统；参数估计；非迭代方法；二次型    

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Iterative HOEO fusion strategy: a promising tool for enhancing bearing fault feature

《机械工程前沿（英文）》 2023年 第18卷 第1期 doi: 10.1007/s11465-022-0725-z

摘要： As parameter independent yet simple techniques, the energy operator (EO) and its variants have received considerable attention in the field of bearing fault feature detection. However, the performances of these improved EO techniques are subjected to the limited number of EOs, and they cannot reflect the non-linearity of the machinery dynamic systems and affect the noise reduction. As a result, the fault-related transients strengthened by these improved EO techniques are still subject to contamination of strong noises. To address these issues, this paper presents a novel EO fusion strategy for enhancing the bearing fault feature nonlinearly and effectively. Specifically, the proposed strategy is conducted through the following three steps. First, a multi-dimensional information matrix (MDIM) is constructed by performing the higher order energy operator (HOEO) on the analysis signal iteratively. MDIM is regarded as the fusion source of the proposed strategy with the properties of improving the signal-to-interference ratio and suppressing the noise in the low-frequency region. Second, an enhanced manifold learning algorithm is performed on the normalized MDIM to extract the intrinsic manifolds correlated with the fault-related impulses. Third, the intrinsic manifolds are weighted to recover the fault-related transients. Simulation studies and experimental verifications confirm that the proposed strategy is more effective for enhancing the bearing fault feature than the existing methods, including HOEOs, the weighting HOEO fusion, the fast Kurtogram, and the empirical mode decomposition.

关键词： higher order energy operator     fault diagnosis     manifold learning     rolling element bearing     information fusion    

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TRANSLATING THE MULTI-ACTOR APPROACH TO RESEARCH INTO PRACTICE USING A WORKSHOP APPROACH FOCUSING ON

《农业科学与工程前沿（英文）》 2021年 第8卷 第3期   页码 460-473 doi: 10.15302/J-FASE-2021416

摘要：

The EIP-Agri multiactor approach was exemplified during a 3-day workshop with 63 project participants from the EU H2020 funded project “Redesigning European cropping systems based on species MIXtures”. The objective was to share firsthand experience of participatory research among researchers who were mostly not familiar with this approach. Workshop participants were divided into smaller multidisciplinary groups and given the opportunity to interact with representatives from eight actor positions in the value chain of the agrifood cooperative Terrena located in Western France. The four stages of the workshop were: (1) key actor interviews, (2) sharing proposed solutions for overcoming barriers, and (3) developing possible interdisciplinary concepts. Expressions of frustration were recorded serving both as a motivation for group members to become more aware of the scientific concerns and practices of their colleagues, as well as a recognition that some researchers have better skills integrating qualitative approaches than others. Nevertheless, the workshop format was an effective way to gain a common understanding of the pertinent issues that need to be addressed to meet overall multiactor-approach objectives. Working with the actor networks was identified and emphasized as a means to overcome existing barriers between academia and practice in order to coproduce a shared vision of the benefits of species mixture benefits.

 

关键词： agroecology     codesign     intercropping     knowledge sharing     participatory methods    

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Governance approach to China’s environmental challenges: Towards a theoretical synthesis

QI Ye, XUE Lan, ZHANG Lingyun

《环境科学与工程前沿（英文）》 2007年 第1卷 第4期   页码 385-400 doi: 10.1007/s11783-007-0066-5

摘要： This paper reviewed recent research in environmental governance as a response to environmental challenges at various spatial, temporal and administrative scales. It documented the shift of approach from regulation to governance, and attempted to provide a comprehensive understanding why and how the transformation occurred. It also described major factors and forces of environmental governance, and discussed research advance in environmental governance theory. Finally, this paper summarized recent research findings on environmental governance in China, and listed policy recommendation for enhancing the governance.

关键词： environmental governance     approach     temporal     regulation     various    

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Comparison of surgical indications for hysterectomy by age and approach in 4653 Chinese women

null

《医学前沿（英文）》 2014年 第8卷 第4期   页码 464-470 doi: 10.1007/s11684-014-0338-y

摘要：

Approximately one million hysterectomies are performed each year in China. However, national data regarding the indications and the surgical approaches for hysterectomy are lacking. The aim of this study was to examine the surgical indications for hysterectomy in different age groups and the relative merits of different surgical approaches for hysterectomy in Chinese women. Clinical data from 4653 cases of hysterectomy performed in Tongji Hospital from 2004 to 2009 were analysed. Hysterectomy was most commonly performed among women aged 40--49 years (2299; 49.4%). Overall, colporrhagia and abdominal pain were the two most common indications for hysterectomy. The most common indications by age groups were as follows: malignant ovarian tumour,<20 years; malignant uterine tumour, 20--29 and 30--39 years; uterine myoma, 40--49 and 50--59 years; and uterine prolapse, 60--69 and>70 years. The proportion of malignant aetiology also varied by age, being the highest in women aged<20 years (75.0%) and the lowest in those aged 40--49 years (19.9%). Approximately 35% women who had hysterectomies also had concomitant bilateral oophorectomy. The lowest rate of oophorectomy occurred in women aged 30--39 years (15.8%), whereas the highest rate was in those aged 50--59 years (75.9%). The abdominal surgical approach was used in 84% of all hysterectomies. Surgeries using the vaginal approach required a significantly shorter operating time (118 min average) than all other approaches (P<0.05). Both the amount of bleeding and the blood transfusion volume required were smaller in vaginal approaches, with no significant differences between the others. The surgical approaches used were also related to the scope of surgery. Both the surgical indications and the rates of bilateral oophorectomy varied by age. In terms of both operating time and the amount of bleeding and blood transfusion volume required, the vaginal approach was superior to all other surgical approaches.

关键词： hysterectomy     surgical indications     surgical approach     bilateral oophorectomy    

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自适应最优相关间隔选择的多普勒频偏估计算法

张彭,毕光国,曹秀英,袁晓辉

《中国工程科学》 2007年 第9卷 第6期   页码 71-76

摘要：

在信道自相关特性的多普勒频偏估计算法的基础上，分析了存在的估计性能不受信噪比和频偏变化 影响的最优相关间隔。利用该特性提出一种逐次缩小搜索范围的迭代（CIO，correlation唱interval optimized）算法，实 现对其搜索和最大多普勒频偏的估计。通过仿真证明理论分析的正确及算法的有效性。与传统基于相关估计算 法相比，该算法自适应于信噪比和频偏变化，估计性能基本上独立于信噪比和频偏的变化，实现多普勒频偏的 直接性能估计。

关键词： 多普勒频偏     自相关     最优化     迭代    

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Hierarchical approach for fatigue cracking performance evaluation in asphalt pavements

Ibrahim ONIFADE, Yared DINEGDAE, Björn BIRGISSON

《结构与土木工程前沿（英文）》 2017年 第11卷 第3期   页码 257-269 doi: 10.1007/s11709-017-0410-1

摘要： In this paper, a hierarchical approach is proposed for the evaluation of fatigue cracking in asphalt concrete pavements considering three different levels of complexities in the representation of the material behaviour, design parameters characterization and the determination of the pavement response as well as damage computation. Based on the developed hierarchical approach, three damage computation levels are identified and proposed. The levels of fatigue damage analysis provides pavement engineers a variety of tools that can be used for pavement analysis depending on the availability of data, required level of prediction accuracy and computational power at their disposal. The hierarchical approach also provides a systematic approach for the understanding of the fundamental mechanisms of pavement deterioration, the elimination of the empiricism associated with pavement design today and the transition towards the use of sound principles of mechanics in pavement analysis and design.

关键词： fatigue cracking     energy based     crack initiation     mechanistic approach     pavement analysis    

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Critical flow-storm approach to total maximum daily load (TMDL) development: an analytical conceptual

Zhang Harry, Yu Shaw

《环境科学与工程前沿（英文）》 2008年 第2卷 第3期   页码 267-273 doi: 10.1007/s11783-008-0058-0

摘要： One of the key challenges in the total maximum daily load (TMDL) development process is how to define the critical condition for a receiving waterbody. The main concern in using a continuous simulation approach is the absence of any guarantee that the most critical condition will be captured during the selected representative hydrologic period, given the scarcity of long-term continuous data. The objectives of this paper are to clearly address the critical condition in the TMDL development process and to compare continuous and event-based approaches in defining critical condition during TMDL development for a waterbody impacted by both point and nonpoint source pollution. A practical, event-based critical flow-storm (CFS) approach was developed to explicitly addresses the critical condition as a combination of a low stream flow and a storm event of a selected magnitude, both having certain frequencies of occurrence. This paper illustrated the CFS concept and provided its theoretical basis using a derived analytical conceptual model. The CFS approach clearly defined a critical condition, obtained reasonable results and could be considered as an alternative method in TMDL development.

关键词： representative hydrologic     occurrence     simulation approach     scarcity     alternative    

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标题 作者 时间 类型 操作

Applications of traditional pump design theory to artificial heart and CFD simulation

WANG Yingpeng, SONG Xinwei, YING Chuntong

期刊论文

Wavelet-based iterative data enhancement for implementation in purification of modal frequency for extremely

Hassan YOUSEFI, Alireza TAGHAVI KANI, Iradj MAHMOUDZADEH KANI, Soheil MOHAMMADI

期刊论文

Iterative finite element model of nonlinear viscoplastic analyses for blended granular porous media

WU Yuching, ZHU Cimian

期刊论文

Improving prodeoxyviolacein production via multiplex SCRaMbLE iterative cycles

Juan Wang, Bin Jia, Zexiong Xie, Yunxiang Li, Yingjin Yuan

期刊论文

A fast compound direct iterative algorithm for solving transient line contact elastohydrodynamic lubrication

null

期刊论文

模糊迭代学习方法及高层建筑结构地震响应控制的数值模拟

汪权,王建国,张鸣祥

期刊论文

针对主动磁悬浮轴承干扰抑制的一类结合迭代学习控制与干扰观测器的解决方法

Ze-zhi TANG, Yuan-jin YU, Zhen-hong LI, Zheng-tao DING

期刊论文

适于低成本嵌入式硬件的2R-1C模型非迭代参数估计

Mitar SIMIĆ, Zdenka BABIĆ, Vladimir RISOJEVIĆ, Goran M. STOJANOVIĆ

期刊论文

Iterative HOEO fusion strategy: a promising tool for enhancing bearing fault feature

期刊论文

TRANSLATING THE MULTI-ACTOR APPROACH TO RESEARCH INTO PRACTICE USING A WORKSHOP APPROACH FOCUSING ON

期刊论文

Governance approach to China’s environmental challenges: Towards a theoretical synthesis

QI Ye, XUE Lan, ZHANG Lingyun

期刊论文

Comparison of surgical indications for hysterectomy by age and approach in 4653 Chinese women

null

期刊论文

自适应最优相关间隔选择的多普勒频偏估计算法

张彭,毕光国,曹秀英,袁晓辉

期刊论文

Hierarchical approach for fatigue cracking performance evaluation in asphalt pavements

Ibrahim ONIFADE, Yared DINEGDAE, Björn BIRGISSON

期刊论文

Critical flow-storm approach to total maximum daily load (TMDL) development: an analytical conceptual

Zhang Harry, Yu Shaw

期刊论文