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一种通用的基于斯托克斯流的复杂流束轮廓工程方法 Article

杨振宇, 南浪, 岑浩璋

《工程（英文）》 2021年 第7卷 第5期   页码 655-662 doi: 10.1016/j.eng.2021.02.008

摘要：

为了在微流控管道中实现诸如混合强化、反应控制和材料合成等应用，经常需要编辑其中的流束轮廓。传统的流束轮廓编辑方法通过激发惯性二次流，使管道中流体重新分布，然而在惯性流可以忽略的微流控环境中，难以借助这类方法形成流束轮廓。传统方法使用的对称式管道内结构也限制了可以创造的流束轮廓的多样性。此外，这类方法生成的每个流束轮廓均对应一个严格定义的特定流动环境，因而在有变化的流动环境中，难以再现这些轮廓。为了解决上述问题，我们提出一种基于非惯性二次流的工程方法来编辑流束轮廓：在微管道内部署一系列级联的具有不同几何形状的阶梯来操控处于斯托克斯流范围内的流体；通过调整这些微阶梯的形状可以定制输出任意的流束轮廓；设计数值式流束轮廓预测程序，可快速预测以任意次序排列的预定义的微阶梯所输出的流束轮廓。该方法可用于生成包括非对称流束轮廓在内的各种稳定的流束轮廓，并且广泛适用于多种微流控流动环境，促进对复杂微流场的预测和设计。

关键词： 微流控     流束轮廓     斯托克斯流     流体动力学聚焦     流动塑形    

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Numerical study and control method of interaction of nucleation and boundary layer separation in condensing flow

Liansuo AN , Zhi WANG , Zhonghe HAN ,

《能源前沿（英文）》 2009年 第3卷 第3期   页码 254-261 doi: 10.1007/s11708-009-0047-4

摘要： The spontaneous nucleation flow in turbine cascade was numerically studied. The model was implemented within a full Navier–Stokes viscous flow solution procedure and the process of condensation was calculated by the quadrature method of moments that shows good accuracy with very broad size distributions. Results were presented for viscous and inviscous flow, showing the influence of boundary layer separation and wake vortices on spontaneous nucleation. The results show that the degree of flow separation in wet steam flow is greater than that in superheated steam flow due to condensation shock and that the loss cannot be neglected. Furthermore, the impact of boundary layer separation and wake vortices on velocity profiles and its implications for profile loss were considered. The calculations showed that layer separation and wake vortices influence nucleation rate, leading to different droplet distributions. A method for controlling homogeneous nucleation and for reducing degree of flow separation in high-speed transonic wet steam flow was presented. The liquid phase parameter distribution is sensitive to the suction side profile of turbine cascade, which impacts the nucleation rate distribution leading to different droplet distributions and affects the degree of flow separation. The numerical study provides a practical design method for turbine blade to reduce wetness losses.

关键词： wet steam     two-phase flow     spontaneous condensation     numerical simulation     flow separation     profile loss    

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Influence of surface cracking, anchor head profile, and anchor head size on cast-in headed anchors in

《结构与土木工程前沿（英文）》   页码 1163-1187 doi: 10.1007/s11709-023-0987-5

摘要： In this study, the concrete cone capacity, concrete cone angle, and load–displacement response of cast-in headed anchors in geopolymer concrete are explored using numerical analyses. The concrete damaged plasticity (CDP) model in ABAQUS is used to simulate the behavior of concrete substrates. The tensile behavior of anchors in geopolymer concrete is compared with that in normal concrete as well as that predicted by the linear fracture mechanics (LFM) and concrete capacity design (CCD) models. The results show that the capacity of the anchors in geopolymer concrete is 30%–40% lower than that in normal concrete. The results also indicate that the CCD model overestimates the capacity of the anchors in geopolymer concrete, whereas the LFM model provides a much more conservative prediction. The extent of the difference between the predictions by the numerical analysis and those of the above prediction models depends on the effective embedment depth of the anchor and the anchor head size. The influence of concrete surface cracking on the capacity of the anchor is shown to depend on the location of the crack and the effective embedment depth. The influence of the anchor head profile on the tensile capacity of the anchors is found to be insignificant.

关键词： cast-in anchor     concrete cone capacity     geopolymer concrete     head size     surface crack     anchor profile    

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Robust energy-efficient train speed profile optimization in a scenario-based position–time–speed network

《工程管理前沿（英文）》 2021年 第8卷 第4期   页码 595-614 doi: 10.1007/s42524-021-0173-1

摘要： Train speed profile optimization is an efficient approach to reducing energy consumption in urban rail transit systems. Different from most existing studies that assume deterministic parameters as model inputs, this paper proposes a robust energy-efficient train speed profile optimization approach by considering the uncertainty of train modeling parameters. Specifically, we first construct a scenario-based position–time–speed (PTS) network by considering resistance parameters as discrete scenario-based random variables. Then, a percentile reliability model is proposed to generate a robust train speed profile, by which the scenario-based energy consumption is less than the model objective value at α confidence level. To solve the model efficiently, we present several algorithms to eliminate the infeasible nodes and arcs in the PTS network and propose a model reformulation strategy to transform the original model into an equivalent linear programming model. Lastly, on the basis of our field test data collected in Beijing metro Yizhuang line, a series of experiments are conducted to verify the effectiveness of the model and analyze the influences of parameter uncertainties on the generated train speed profile.

关键词： robust train speed profile     percentile reliability model     scenario-based position–time–speed network     mixed-integer programming    

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New approach to determine the plastic viscosity of self-compacting concrete

M. BENAICHA,X. ROGUIEZ,O. JALBAUD,Y. BURTSCHELL,A. Hafidi ALAOUI

《结构与土木工程前沿（英文）》 2016年 第10卷 第2期   页码 198-208 doi: 10.1007/s11709-015-0327-5

摘要： The rheology of concrete is best measured with the use of a rheometer. The slump flow test gives a good indication of the flowability of the mixture and is therefore still used extensively to judge the workability of SCC mixtures. However, this test presents some defects. The objective of this paper is to develop a new methodology for measuring the workability of a SCC. In this article, we have proposed a correlation between the plastic viscosity of concrete, the time and the characteristics of the flow final profile from the V-funnel coupled to a Plexiglas horizontal channel. The proposed approach, verified by experimental results, represents a simple, economical and usable tool on building site, and it allows to characterize rheologically the SCC from its flow. The comparison between our approach and the experimental values of the plastic viscosity shows that, in a laboratory or on site, instead of using a rheometer we can use our approach to characterize the rheological behavior of a SCC.

关键词： rheology     viscosity     V-funnel     flow profile     rheometer     behavior    

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Torsional behavior of triangular web profile (TRIWP) steel section by experimental study

Fatimah DE’NAN,Hazwani HASAN,Mohd Hanim OSMAN,Sariffudin SAAD

《结构与土木工程前沿（英文）》 2016年 第10卷 第4期   页码 409-419 doi: 10.1007/s11709-016-0358-6

摘要： A triangular web profile (TriWP) is a modified section where the flanges are connected to a web plate of triangular profile. This study examined the torsional behavior of TriWP steel sections and compared to that of the flat web (FW) steel sections. Three types of specimen sizes were used: 180 mm × 75 mm × 5 mm × 2 mm, 200 mm × 100 mm × 8 mm × 6 mm, and 200 mm × 100 mm × 6 mm × 5 mm. All the specimens were loaded vertically until the maximum load was achieved and then the load was released. For both types of specimens, it was observed that the torsional rotation for bigger size [200 mm × 100 mm × 8 mm × 6 mm] were smaller than that of smaller size [180 mm × 75 mm × 5 mm × 2 mm] of the specimens. At the maximum torsional loading, the experimental result was compared to the theoretical calculation. The comparison showed that the percentage difference ranged from 1.10% to 16.80%. From the graph of torsional load versus rotational angle, the torsional rotation for all TriWP steel sections were smaller than that of the FW steel section under the same torsional loading i.e., 0.2 kNm and 1 kNm. The range between FW and TriWP were 3.74 to 71.83 at 0.2 kNm while 14.5 to 75.1 at 1.0 kNm. The findings were shown that the TriWP steel sections had better resistance against torsion in comparison to FW steel section.

关键词： corrugated web     i-beam     non uniform steel section     torsion resistance     torsion angle     triangular web profile steel section    

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Multi-omics joint analysis revealed the metabolic profile of retroperitoneal liposarcoma

《医学前沿（英文）》 doi: 10.1007/s11684-023-1020-z

摘要： Retroperitoneal liposarcoma (RLPS) is the main subtype of retroperitoneal soft sarcoma (RSTS) and has a poor prognosis and few treatment options, except for surgery. The proteomic and metabolic profiles of RLPS have remained unclear. The aim of our study was to reveal the metabolic profile of RLPS. Here, we performed proteomic analysis (n = 10), metabolomic analysis (n = 51), and lipidomic analysis (n = 50) of retroperitoneal dedifferentiated liposarcoma (RDDLPS) and retroperitoneal well-differentiated liposarcoma (RWDLPS) tissue and paired adjacent adipose tissue obtained during surgery. Data analysis mainly revealed that glycolysis, purine metabolism, pyrimidine metabolism and phospholipid formation were upregulated in both RDDLPS and RWDLPS tissue compared with the adjacent adipose tissue, whereas the tricarboxylic acid (TCA) cycle, lipid absorption and synthesis, fatty acid degradation and biosynthesis, as well as glycine, serine, and threonine metabolism were downregulated. Of particular importance, the glycolytic inhibitor 2-deoxy-D-glucose and pentose phosphate pathway (PPP) inhibitor RRX-001 significantly promoted the antitumor effects of the MDM2 inhibitor RG7112 and CDK4 inhibitor abemaciclib. Our study not only describes the metabolic profiles of RDDLPS and RWDLPS, but also offers potential therapeutic targets and strategies for RLPS.

关键词： RLPS     proteomics     metabolomics     lipidomics     metabolism    

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Topology-independent end-to-end learning model for improving the voltage profile in microgrids-integrated

《能源前沿（英文）》 2023年 第17卷 第2期   页码 211-227 doi: 10.1007/s11708-022-0847-3

摘要： With multiple microgrids (MGs) integrated into power distribution networks in a distributed manner, the penetration of renewable energy like photovoltaic (PV) power generation surges. However, the operation of power distribution networks is challenged by the issues of multiple power flow directions and voltage security. Accordingly, an efficient voltage control strategy is needed to ensure voltage security against ever-changing operating conditions, especially when the network topology information is absent or inaccurate. In this paper, we propose a novel data-driven voltage profile improvement model, denoted as system-wide composite adaptive network (SCAN), which depends on operational data instead of network topology details in the context of power distribution networks integrated with multiple MGs. Unlike existing studies that realize topology identification and decision-making optimization in sequence, the proposed end-to-end model determines the optimal voltage control decisions in one shot. More specifically, the proposed model consists of four modules, Pre-training Network and modified interior point methods with adversarial networks (Modified IPMAN) as core modules, and discriminator generative adversarial network (Dis-GAN) and Volt convolutional neural network (Volt-CNN) as ancillary modules. In particular, the generator in SCAN is trained by the core modules in sequence so as to form an end-to-end mode from data to decision. Numerical experiments based on IEEE 33-bus and 123-bus systems have validated the effectiveness and efficiency of the proposed method.

关键词： end-to-end learning     microgrids     voltage profile improvement     generative adversarial network    

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New nonlinear stiffness actuator with predefined torque‒deflection profile

《机械工程前沿（英文）》 2023年 第18卷 第1期 doi: 10.1007/s11465-022-0721-3

摘要： A nonlinear stiffness actuator (NSA) could achieve high torque/force resolution in low stiffness range and high bandwidth in high stiffness range, both of which are beneficial for physical interaction between a robot and the environment. Currently, most of NSAs are complex and hardly used for engineering. In this paper, oriented to engineering applications, a new simple NSA was proposed, mainly including leaf springs and especially designed cams, which could perform a predefined relationship between torque and deflection. The new NSA has a compact structure, and it is lightweight, both of which are also beneficial for its practical application. An analytical methodology that maps the predefined relationship between torque and deflection to the profile of the cam was developed. The optimal parameters of the structure were given by analyzing the weight of the NSA and the mechanic characteristic of the leaf spring. Though sliding friction force is inevitable because no rollers were used in the cam-based mechanism, the sliding displacement between the cam and the leaf spring is very small, and consumption of sliding friction force is very low. Simulations of different torque‒deflection profiles were carried out to verify the accuracy and applicability of performing predefined torque‒deflection profiles. Three kinds of prototype experiments, including verification experiment of the predefined torque‒deflection profile, torque tracking experiment, and position tracking experiment under different loads, were conducted. The results prove the accuracy of performing the predefined torque‒deflection profile, the tracking performance, and the interactive performance of the new NSA.

关键词： compliant actuator     nonlinear stiffness actuator     nonlinear spring     predefined torque−deflection profile    

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Nonlinear dynamic behaviour of a cam mechanism with oscillating roller follower in presence of profile

Walha LASSAAD, Tounsi MOHAMED, Driss YASSINE, Chaari FAKHER, Fakhfakh TAHER, Haddar MOHAMED

《机械工程前沿（英文）》 2013年 第8卷 第2期   页码 127-136 doi: 10.1007/s11465-013-0254-x

摘要：

In this paper we investigate the nonlinear dynamic behaviour of a cam mechanism with oscillating roller follower in presence of defects. The nonlinear developed lumped-mass model includes eight degrees of freedom with two nonlinear hertzian contacts. The first one is located between cam and first roller while the second is between second roller and the sliding rod. The nonlinear dynamic behaviour is described by second order differential equations which are resolved by using the implicit Newmark algorithm combined with the Newton-Raphson iterative scheme. The influence of the cam profile error on the dynamic behaviour is also investigated.

关键词： cam     nonlinear behaviour     oscillating roller follower     profile error    

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Relationship of endothelial nitric oxide synthase gene polymorphism with blood pressure, lipid profile

TANG Zhongzhi, LI Junyao, YANG Jianhong

《医学前沿（英文）》 2008年 第2卷 第2期   页码 178-181 doi: 10.1007/s11684-008-0033-y

摘要： To study the relationship of the polymorphism of endothelial nitric oxide synthase (eNOS) gene and blood pressure, lipid profiles and blood glucose level. By using PCR-RFLP, the eNOS Glu298Asp gene polymorphism was detected in 184 patients with essential hypertension and 196 matched healthy individuals with normal blood pressure. Taking into account eNOS Glu298Asp polymorphisms, the relationship of blood pressure with triglycerides (TG), total cholesterol (TC), high density lipoprotein (HDL), low density lipoprotein (LDL) and blood glucose level was analyzed. The distribution of eNOS Glu298Asp polymorphism had no significant difference between different blood pressure groups and gender groups, but there was a significant difference between different age groups, diastolic blood pressure groups or BMI groups ( < 0.05). Asp/Asp genotype significantly increased the risk of hypertension in individuals with serum TC above 5.4 mmol/L ( = 0.03, = 2.65). eNOS Glu298Asp polymorphism and serum lipid could synergistically modulate the blood pressure. eNOS Asp/Asp genotype could significantly increase the risk of hypertension in individuals with serum TC over 5.4 mmol/L. eNOS Glu298Asp in combination with serum TC could be used to predict the risk of hypertension.
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Predicting beach profile evolution with group method data handling-type neural networks on beaches with

M. A. LASHTEH NESHAEI, M. A. MEHRDAD, N. ABEDIMAHZOON, N. ASADOLLAHI

《结构与土木工程前沿（英文）》 2013年 第7卷 第2期   页码 117-126 doi: 10.1007/s11709-013-0205-y

摘要： A major goal of coastal engineering is to develop models for the reliable prediction of short- and long-term near shore evolution. The most successful coastal models are numerical models, which allow flexibility in the choice of initial and boundary conditions. In the present study, evolutionary algorithms (EAs) are employed for multi-objective Pareto optimum design of group method data handling (GMDH)-type neural networks that have been used for bed evolution modeling in the surf zone for reflective beaches, based on the irregular wave experiments performed at the Hydraulic Laboratory of Imperial College (London, UK). The input parameters used for such modeling are significant wave height, wave period, wave action duration, reflection coefficient, distance from shoreline and sand size. In this way, EAs with an encoding scheme are presented for evolutionary design of the generalized GMDH-type neural networks, in which the connectivity configurations in such networks are not limited to adjacent layers. Also, multi-objective EAs with a diversity preserving mechanism are used for Pareto optimization of such GMDH-type neural networks. The most important objectives of GMDH-type neural networks that are considered in this study are training error (TE), prediction error (PE), and number of neurons ( ). Different pairs of these objective functions are selected for two-objective optimization processes. Therefore, optimal Pareto fronts of such models are obtained in each case, which exhibit the trade-offs between the corresponding pair of the objectives and, thus, provide different non-dominated optimal choices of GMDH-type neural network model for beach profile evolution. The results showed that the present model has been successfully used to optimally prediction of beach profile evolution on beaches with seawalls.

关键词： beach profile evolution     genetic algorithms     group method of data handling     Pareto     reflective beaches    

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Vortex-induced vibration of stay cable under profile velocity using CFD numerical simulation method

Wenli CHEN, Hui LI,

《结构与土木工程前沿（英文）》 2009年 第3卷 第4期   页码 357-363 doi: 10.1007/s11709-009-0060-z

摘要： Vortex-induced vibration (VIV) of a stay cable subjected to a wind profile is numerically simulated through combining computational fluid dynamics (CFD) code CFX 10.0 and computational structural dynamics (CSD) code ANSYS 10.0. A stay cable with the inclined angle of 30° is used as the numerical model. Under a profile of mean wind speed, unsteady aerodynamic lift coefficients of the cable have been analyzed in both time domain and frequency domain when VIV occurs. The results indicate that the lift coefficient wave response of the stay cable under a wind profile is different from that of an infinitely long cable under a uniform flow in water (i.e., without consideration of profile) obtained by direct numerical simulation. Cable oscillations can severely affect the unsteady aerodynamic frequencies, change flow field distribution near the cable and affect the vortex shedding in the wake.

关键词： stay cable     fluid-structure interaction     numerical simulation     vortex-induced vibration    

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非均质储层CO2泡沫调驱注入参数优化实验研究

赵金省,谭俊领,古正富,刘笑春

《中国工程科学》 2012年 第14卷 第11期   页码 88-93

摘要：

针对华庆长6储层地层水的特点，以综合起泡能力为评价指标，对常用的6种起泡剂进行了优选，优选出ZY-1型起泡剂，起泡剂浓度为0.5 %，稳泡剂浓度为764 mg/L。在此基础上，采用渗透率级差接近的两组并联岩心，进行了注入方式和注入段塞组合的优化实验。结果表明，地下起泡方式，即CO2和起泡剂交替注入的方式可以在高渗透层中形成较高的封堵压差，具有较好的驱油效果。最优的段塞组合是0.2倍孔隙体积的起泡剂+0.4倍孔隙体积的CO2气体，总注入段塞是0.6倍孔隙体积。

关键词： 非均质储层     CO2泡沫     调驱     注入参数     实验研究    

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Numerical study of internal flow field and flow passage improvement of an inlet particle separator

Florian PAOLI, Tong WANG

《能源前沿（英文）》 2011年 第5卷 第4期   页码 386-397 doi: 10.1007/s11708-011-0156-8

摘要： By performing gas flow field numerical simulations for several inlet Reynolds numbers (from 2 × 10 to 9 × 10 ) and byflow ratios (from 10% to 20%), the present study has proposed to improve the flow passage of an inlet particle separator. An adjacent objective of the study is to lower pressure losses of the inlet particle separator (IPS). No particle has been included in the gas flow for a -epsilon turbulence model. The velocity distribution in different sections and the pressure coefficient along the duct have been analyzed, which indicates that there exist important low-velocity regions and vortices in the separation area. Therefore, the profile of streamlines along the original passage has been considered. This profile illustrated a vacuum region in the same area. All investigations suggest that the separation area is the most critical one for fulfilling the objective on pressure losses limitation. Then the flow passage improvement method has focused on the separation area. An improved shape has been designed in order to suit smoothly to the streamlines in this region. Similar numerical studies as those for the original shape have been conducted on this improved shape, confirming some considerable enhancements compared with the original shape. The significant vortices which appear in the original shape reduce in amount and size. Besides, pressure losses are greatly decreased in both outlets (up to 30% for high Reynolds number) and the flow is uniform at the main outlet. Subsequent engineering surveys could rely on expressions obtained for in both outlets which extend the pressure losses for a wide range of inlet Reynolds numbers. As a result, the numerical calculations demonstrate that the flow passage improvement method applied in this study has succeeded in designing a shape which enhances the flow behavior.

关键词： streamlines     pressure losses     flow passage improvement     inlet particle separator (IPS)    

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标题 作者 时间 类型 操作

一种通用的基于斯托克斯流的复杂流束轮廓工程方法

杨振宇, 南浪, 岑浩璋

期刊论文

Numerical study and control method of interaction of nucleation and boundary layer separation in condensing flow

Liansuo AN , Zhi WANG , Zhonghe HAN ,

期刊论文

Influence of surface cracking, anchor head profile, and anchor head size on cast-in headed anchors in

期刊论文

Robust energy-efficient train speed profile optimization in a scenario-based position–time–speed network

期刊论文

New approach to determine the plastic viscosity of self-compacting concrete

M. BENAICHA,X. ROGUIEZ,O. JALBAUD,Y. BURTSCHELL,A. Hafidi ALAOUI

期刊论文

Torsional behavior of triangular web profile (TRIWP) steel section by experimental study

Fatimah DE’NAN,Hazwani HASAN,Mohd Hanim OSMAN,Sariffudin SAAD

期刊论文

Multi-omics joint analysis revealed the metabolic profile of retroperitoneal liposarcoma

期刊论文

Topology-independent end-to-end learning model for improving the voltage profile in microgrids-integrated

期刊论文

New nonlinear stiffness actuator with predefined torque‒deflection profile

期刊论文

Nonlinear dynamic behaviour of a cam mechanism with oscillating roller follower in presence of profile

Walha LASSAAD, Tounsi MOHAMED, Driss YASSINE, Chaari FAKHER, Fakhfakh TAHER, Haddar MOHAMED

期刊论文

Relationship of endothelial nitric oxide synthase gene polymorphism with blood pressure, lipid profile

TANG Zhongzhi, LI Junyao, YANG Jianhong

期刊论文

Predicting beach profile evolution with group method data handling-type neural networks on beaches with

M. A. LASHTEH NESHAEI, M. A. MEHRDAD, N. ABEDIMAHZOON, N. ASADOLLAHI

期刊论文

Vortex-induced vibration of stay cable under profile velocity using CFD numerical simulation method

Wenli CHEN, Hui LI,

期刊论文

非均质储层CO2泡沫调驱注入参数优化实验研究

赵金省,谭俊领,古正富,刘笑春

期刊论文

Numerical study of internal flow field and flow passage improvement of an inlet particle separator

Florian PAOLI, Tong WANG

期刊论文