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期刊论文 34

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最小二乘法 3

LS算法 1

S-N曲线 1

square-twist折纸 1

主动噪声控制（ANC）；过滤扩展最小均方（FXLMS）；模拟计算；遗传算法；内点法 1

二维正交方阵码（2D-OOSC） 1

光学等离子体重建；边缘检测；全局对比度；最小二乘法；EAST托卡马克 1

光码分多址（OCDMA） 1

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四元数；梯度；信号处理；最小均方算法；非线性自适应滤波；波束形成 1

多址干扰MUI 1

多输入多输出 1

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折纸超材料 1

抽象；最小均方误差重建自组织学习（Lmser）；认知；形象思维；抽象思维；综合推理 1

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基于刚性与非刚性Square-Twist胞元混合排布的折纸超材料设计与性能编程研究 Article

马家耀, 臧世玺, 陈焱, 由衷

《工程（英文）》 2022年 第17卷 第10期   页码 82-92 doi: 10.1016/j.eng.2022.02.015

摘要： 本文通过将一系列不同类型的square-twist 折纸胞元进行空间排布，设计了一种新型折纸超材料。首先建立了超材料胞元的空间排布规则，保证了相邻胞元山-谷线折痕的几何匹配。本工作为可编程折纸超材料的设计提供了新的思路，在机械等工程领域具有广阔的应用前景。

关键词： 折纸超材料     超材料     square-twist折纸     非周期性排布     可编程性    

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Correlation of Twist upregulation and senescence bypass during the progression and metastasis of cervical

null

《医学前沿（英文）》 2014年 第8卷 第1期   页码 106-112 doi: 10.1007/s11684-014-0307-5

摘要：

Cervical carcinoma is associated with high propensity for local invasion and lymph node metastasis. However, the molecular alterations that drive progression and metastasis of cervical cancer remain unclear. Cellular senescence has been proposed as the mechanism that protects an organism against cancer progression and metastasis. In addition, Twist, a basic helix-loop-helix transcription factor, has been suggested as an oncogene because it is overexpressed in many types of human cancer. This gene also exhibits a positive function in regulating invasion and metastasis. In this study, Twist was strongly and positively expressed in normal tissue, squamous cell carcinoma (SCC) IA--IIA, and SCC IIB--IIIB (4.3%, 44%, and 88.9%, respectively). The strong positive expressions of the senescence marker CBX3 were 39.1%, 32%, and 15.6%, respectively. The strong positive expressions of Twist in the SCC groups with or without lymph node metastasis were 80.8% and 50%. For CBX3, such expressions were 7.7% and 29.5%, respectively. Results also showed that the expression of Twist was inversely correlated with that of CBX3. Moreover, the knockdown of Twist with target siRNA in SiHa triggered the induction of the chromatin marker of the cellular senescence CBX3 and senescence-associated β-galactosidase activity. Our results suggested that the expression of Twist increased during the progression and metastasis of cervical cancer. Furthermore, Twist-induced senescence bypass is important in this process.

关键词： cervical cancer     senescence     Twist     CBX3     lymph node metastasis    

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Usability perceptions and beliefs about smart thermostats by chi-square test, signal detection theory

Pedro PONCE, Therese PEFFER, Arturo MOLINA

《能源前沿（英文）》 2019年 第13卷 第3期   页码 522-538 doi: 10.1007/s11708-018-0562-2

摘要： It is well known that smart thermostats (STs) have become key devices in the implementation of smart homes; thus, they are considered as primary elements for the control of electrical energy consumption in households. Moreover, energy consumption is drastically affected when the end users select unsuitable STs or when they do not use the STs correctly. Furthermore, in future, Mexico will face serious electrical energy challenges that can be considerably resolved if the end users operate the STs in a correct manner. Hence, it is important to carry out an in-depth study and analysis on thermostats, by focusing on social aspects that influence the technological use and performance of the thermostats. This paper proposes the use of a signal detection theory (SDT), fuzzy detection theory (FDT), and chi-square (CS) test in order to understand the perceptions and beliefs of end users about the use of STs in Mexico. This paper extensively shows the perceptions and beliefs about the selected thermostats in Mexico. Besides, it presents an in-depth discussion on the cognitive perceptions and beliefs of end users. Moreover, it shows why the expectations of the end users about STs are not met. It also promotes the technological and social development of STs such that they are relatively more accepted in complex electrical grids such as smart grids.

关键词： thermostats     perceptions     beliefs     signal detection theory (SDT)     fuzzy signal detection theory (FSDT)     chi-square (CS) test    

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Theoretical study on the confine-stiffening effect and fractal cracking of square concrete filled steel

《结构与土木工程前沿（英文）》 2021年 第15卷 第6期   页码 1317-1336 doi: 10.1007/s11709-021-0763-3

摘要： Tension stress in steel-concrete composite is widely observed in engineering design. Based on an experimental program on tension performance of three square concrete-filled tubes (SCFT), the tension theory of SCFT is proposed using a mechanics-based approach. The tension stiffening effect, the confining strengthening effect and the confining stiffening effect, observed in tests of SCFTs are included in the developed tension theory model. Subsequently, simplified constitutive models of steel and concrete are proposed for the axial tension performance of SCFT. Based on the MSC.MARC software, a special fiber beam-column element is proposed to include the confining effect of SCFTs under tension and verified. The proposed analytical theory, effective formulas, and equivalent constitutive laws are extensively verified against three available tests reported in the literature on both global level (e.g., load-displacement curves) and strain level. The experimental verification proves the accuracy of the proposed theory and formulations in simulating the performance of SCFT members under tension with the capability to accurately predict the tensile strength and stiffness enhancements and realistically simulate the fractal cracking phenomenon.

关键词： square concrete filled tubes     confine-stiffening     confine-strengthening     fractal cracking     fracture    

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Assessment of global and regional left ventricular twist and displacement in anterior myocardial infarction

Wei HAN MM, Ming-Xing XIE MD, Qing LV MD, Xin-Fang WANG MD, Li ZHANG MM,

《医学前沿（英文）》 2010年 第4卷 第1期   页码 71-76 doi: 10.1007/s11684-010-0006-9

摘要： The recent development of 2-dimensional strain (2D strain) imaging can provide a powerful alternative for assessing left ventricular (LV) torsion. This study was conducted to evaluate the global and regional left ventricular twist by 2D strain in patients with anterior wall myocardial infarction (AMI). A total of 55 AMI patients were divided into two groups according to their ejection fraction (EF) values (group A: LVEF≥50%; group B: LVEF<50%), and 35 normal people served as the control group. Using 2-dimensional strain software, global and regional LV rotation and displacement were obtained at two planes. Compared with the control group, patients of group A showed reduced peak LV twist of the anterior and anterior-septal wall (9.26±1.89 10.74±2.67; 9.71±1.71 11.36±2.29, both <0.05), but the radial displacement and global twist were maintained (>0.05). Differently, regional and global LV twist and radial displacement in patients of group B deceased significantly, especially in the anterior and anterior-septal wall, as compared with patients in the control or group A (both <0.05). Moreover, a strong correlation was noted between peak twist and radial displacement; the twist-displacement loop was markedly distorted in patients of group B. This study demonstrated that 2D strain has a potential ability for quantification of left ventricular global and segment twist and radial displacement in patients with coronary artery disease.

关键词： echocardiography     twist     two-dimensional strain imaging     coronary artery disease    

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Existence of complete band gaps in 2D steel-water phononic crystal with square lattice

Cunfu HE, Huanyu ZHAO, Ruiju WEI, Bin WU

《机械工程前沿（英文）》 2010年 第5卷 第4期   页码 450-454 doi: 10.1007/s11465-010-0105-y

摘要： This paper theoretically and experimentally studies the existence of complete band gaps in two-dimensional (2D) phononic crystal consisting of parallel steel rods in water with square lattice. The band structure of phononic crystal is calculated by a plane wave expansion (PWE) method. Based on the well-known ultrasonic immersion transmission technique, the overlapping transmission spectra of acoustic waves, a complete band gap, is experimentally measured along the two high-symmetry directions of the first irreducible Brillouin zone. There is a very good agreement between the experimental result and the range of frequencies of the complete band gap.

关键词： phononic crystal     plane wave expansion (PWE) method     experimental study    

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Day-ahead electricity price forecasting using back propagation neural networks and weighted least square

S. Surender REDDY,Chan-Mook JUNG,Ko Jun SEOG

《能源前沿（英文）》 2016年 第10卷 第1期   页码 105-113 doi: 10.1007/s11708-016-0393-y

摘要： This paper proposes the day-ahead electricity price forecasting using the artificial neural networks (ANN) and weighted least square (WLS) technique in the restructured electricity markets. Price forecasting is very important for online trading, e-commerce and power system operation. Forecasting the hourly locational marginal prices (LMP) in the electricity markets is a very important basis for the decision making in order to maximize the profits/benefits. The novel approach proposed in this paper for forecasting the electricity prices uses WLS technique and compares the results with the results obtained by using ANNs. To perform this price forecasting, the market knowledge is utilized to optimize the selection of input data for the electricity price forecasting tool. In this paper, price forecasting for Pennsylvania-New Jersey-Maryland (PJM) interconnection is demonstrated using the ANNs and the proposed WLS technique. The data used for this price forecasting is obtained from the PJM website. The forecasting results obtained by both methods are compared, which shows the effectiveness of the proposed forecasting approach. From the simulation results, it can be observed that the accuracy of prediction has increased in both seasons using the proposed WLS technique. Another important advantage of the proposed WLS technique is that it is not an iterative method.

关键词： day-ahead electricity markets     price forecasting     load forecasting     artificial neural networks     load serving entities    

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最小二乘支持向量机的扩展及其在时间序列预测中的应用

向小东

《中国工程科学》 2008年 第10卷 第11期   页码 89-92

摘要：

根据时间序列近期数据较远期数据包含有更多未来信息的思想，对最小二乘支持向量机预测方法进行了扩展，得到了更具一般性的最小二乘支持向量机预测模型，给出了扩展后的预测模型具体算法。两个时间序列的预测实例表明，扩展后的预测方法获得了更好的预测效果，提升了最小二乘支持向量机预测方法的价值。

关键词： 最小二乘支持向量机     扩展     时间序列     预测    

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A way to explain the thermal boundary effects on laminar convection through a square duct

Liangbi WANG, Xiaoping GAI, Kun HUANG, Yongheng ZHANG, Xiang YANG, Xiang WU

《能源前沿（英文）》 2010年 第4卷 第4期   页码 496-506 doi: 10.1007/s11708-010-0020-2

摘要： A way using the reformulation of the energy conservation equation in terms of heat flux to explain the thermal boundary effects on laminar convective heat transfer through a square duct is presented. For a laminar convection through a square duct, it explains that on the wall surface, the velocity is zero, but convection occurs for uniform wall heat flux (UWHF) boundary in the developing region due to the velocity gradient term; for uniform wall temperature (UWT) boundary, only diffusion process occurs on the wall surface because both velocity and velocity gradient do not contribute to convection; for UWHF, the largest term of the gradient of velocity components (the main flow velocity) on the wall surface takes a role in the convection of the heat flux normal to the wall surface, and this role exists in the fully developed region. Therefore, a stronger convection process occurs for UWHF than for UWT on the wall surface. The thermal boundary effects on the laminar convection inside the flow are also detailed.

关键词： convective transport     heat transfer     mass transfer     laminar flow     thermal boundary effects    

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Numerical study on natural convection in a square enclosure containing a rectangular heated cylinder

Jianhua LU, Zhaoli GUO, Zhenhua CHAI, Baochang SHI,

《能源前沿（英文）》 2009年 第3卷 第4期   页码 373-380 doi: 10.1007/s11708-009-0078-x

摘要： In this paper, the natural convection in a square enclosure with a rectangular heated cylinder is investigated via the lattice Boltzmann method. A detailed study is conducted on the effect of the cylinder width and the Rayleigh number on the fluid flow and heat transfer. The flow structures and heat transfer patterns are classified into eight buoyant regimes, i.e., four steady regimes, two periodic regimes, one multiple periodic regime, and one chaos regime, two of which are reported for the first time.

关键词： natural convection     buoyant regime     heated cylinder     lattice Boltzmann    

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A new type of quadratic acceleration method

Changqing LI, Menglin LOU,

《结构与土木工程前沿（英文）》 2010年 第4卷 第3期   页码 302-310 doi: 10.1007/s11709-010-0026-1

摘要： The polynomial acceleration method for time history analysis is presented, in which accelerations between several equal neighboring time steps were assumed to be a polynomial function of time interval. With a higher order polynomial used, a higher accuracy can be obtained, but the stability field of the method becomes narrower. When stability field and computational accuracy are taken into account at the same time, the quadratic acceleration method is superior to linear and cubic acceleration methods in choosing the maximum acceptable time step size. It is also shown that the quadratic acceleration method has desirable arithmetic damp, amplitude decay rate and period elongation rate, though its conditional stability restricts its application in stiff structures.

关键词： polynomial acceleration method     convergence     stability     square acceleration method    

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用考虑置信区间长度影响的最小二乘法拟合S-N曲线

杨晓华,金平,姚卫星

《中国工程科学》 2004年 第6卷 第4期   页码 41-43

摘要：

S-N曲线是用名义应力法预测结构疲劳寿命的基础。基于试验疲劳寿命分散的物理机制，提出了一个S-N曲线试验数据处理的加权最小二乘法，此方法中每组数据的权重与该组数据的置信区间成反比。计算结果表明用考虑置信区间长度影响的最小二乘法拟合得到的S-N曲线比用一般最小二乘法得到的S-N曲线具有更高的可靠度，给出的寿命预测结果也更安全。

关键词： 置信区间     疲劳寿命     最小二乘法     S-N曲线    

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Theory analysis and system identification methods on thermal dynamics characteristics of ballscrews

XIA Junyong, HU Youmin, WU Bo, SHI Tielin

《机械工程前沿（英文）》 2008年 第3卷 第4期   页码 408-415 doi: 10.1007/s11465-008-0061-y

摘要： Empirical model of machine tools on thermal error has been widely researched, which can compensate for thermal error to some extent but not suitable for thermal dynamic errors produced by dynamic heat sources. The thermoelastic phenomenon of unidimensional heat transfer of ballscrews influenced by changeable heat sources is analyzed based on the theory of heat transfer. Two methods for system identification (the least square system identification and BP artificial neural network (ANN) system identification) are put forward to establish a dynamic characteristic model of thermal deformation of ballscrews. The model of thermal error of the axis in a feed system of DM4600 vertical miller is established with a fine identification effect. Comparing the results of the two identification methods, the BP ANN system identification is more precise than the least square system identification.

关键词： square system     network     vertical miller     transfer     ANN    

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LSSVM-based approach for refining soil failure criteria and calculating safety factor of slopes

Shiguo XIAO; Shaohong LI

《结构与土木工程前沿（英文）》 2022年 第16卷 第7期   页码 871-881 doi: 10.1007/s11709-022-0863-8

摘要： The failure criteria of practical soil mass are very complex, and have significant influence on the safety factor of slope stability. The Coulomb strength criterion and the power-law failure criterion are classically simplified. Each one has limited applicability owing to the noticeable difference between calculated predictions and actual results in some cases. In the work reported here, an analysis method based on the least square support vector machine (LSSVM), a machine learning model, is purposefully provided to establish a complex nonlinear failure criterion via iteration computation based on strength test data of the soil, which is of more extensive applicability to many problems of slope stability. In particular, three evaluation indexes including coefficient of determination, mean absolute percentage error, and mean square error indicate that fitting precision of the machine learning-based failure criterion is better than those of the linear Coulomb criterion and nonlinear power-law criterion. Based on the proposed LSSVM approach to determine the failure criterion, the limit equilibrium method can be used to calculate the safety factor of three-dimensional slope stability. Analysis of results of the safety factor of two three-dimensional homogeneous slopes shows that the maximum relative errors between the proposed approach and the linear failure criterion-based method and the power-law failure criterion-based method are about 12% and 7%, respectively.

关键词： slope stability     safety factor     failure criterion     least square support vector machine    

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The second short-term warm ischemia after vascular anastomosis did not affect early renal function recovery in renal transplantation: a case report

null

《医学前沿（英文）》 2012年 第6卷 第3期   页码 329-331 doi: 10.1007/s11684-012-0211-9

摘要：

Ischemic postconditioning was defined as rapid intermittent interruptions of blood ?ow in the early phase of reperfusion, which has been found to be protective against renal ischemia-reperfusion injury (IRI) in animal models but not in clinical trials. We describe a case that the allograft renal vein was twisted because of the surgeon’s mistake, which caused the warm ischemia of allograft after reperfusion. The allograft restored blood flow without second reperfusion and cold preservation after 9 min of warm ischemia. The patient was followed up for 3 months and the allograft worked well without complications.

关键词： renal transplantation     vein twist     ischemia-reperfusion injury    

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标题 作者 时间 类型 操作

基于刚性与非刚性Square-Twist胞元混合排布的折纸超材料设计与性能编程研究

马家耀, 臧世玺, 陈焱, 由衷

期刊论文

Correlation of Twist upregulation and senescence bypass during the progression and metastasis of cervical

null

期刊论文

Usability perceptions and beliefs about smart thermostats by chi-square test, signal detection theory

Pedro PONCE, Therese PEFFER, Arturo MOLINA

期刊论文

Theoretical study on the confine-stiffening effect and fractal cracking of square concrete filled steel

期刊论文

Assessment of global and regional left ventricular twist and displacement in anterior myocardial infarction

Wei HAN MM, Ming-Xing XIE MD, Qing LV MD, Xin-Fang WANG MD, Li ZHANG MM,

期刊论文

Existence of complete band gaps in 2D steel-water phononic crystal with square lattice

Cunfu HE, Huanyu ZHAO, Ruiju WEI, Bin WU

期刊论文

Day-ahead electricity price forecasting using back propagation neural networks and weighted least square

S. Surender REDDY,Chan-Mook JUNG,Ko Jun SEOG

期刊论文

最小二乘支持向量机的扩展及其在时间序列预测中的应用

向小东

期刊论文

A way to explain the thermal boundary effects on laminar convection through a square duct

Liangbi WANG, Xiaoping GAI, Kun HUANG, Yongheng ZHANG, Xiang YANG, Xiang WU

期刊论文

Numerical study on natural convection in a square enclosure containing a rectangular heated cylinder

Jianhua LU, Zhaoli GUO, Zhenhua CHAI, Baochang SHI,

期刊论文

A new type of quadratic acceleration method

Changqing LI, Menglin LOU,

期刊论文

用考虑置信区间长度影响的最小二乘法拟合S-N曲线

杨晓华,金平,姚卫星

期刊论文

Theory analysis and system identification methods on thermal dynamics characteristics of ballscrews

XIA Junyong, HU Youmin, WU Bo, SHI Tielin

期刊论文

LSSVM-based approach for refining soil failure criteria and calculating safety factor of slopes

Shiguo XIAO; Shaohong LI

期刊论文

The second short-term warm ischemia after vascular anastomosis did not affect early renal function recovery in renal transplantation: a case report

null

期刊论文