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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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The effect of sea level rise on beach morphology of caspian sea coast

M. A. Lashteh NESHAEI, F. GHANBARPOUR

《结构与土木工程前沿（英文）》 2017年 第11卷 第4期   页码 369-379 doi: 10.1007/s11709-017-0398-6

摘要： Study of beach morphology has been one of the most important issues in coastal engineering research projects. Because of the existence of two important coastal areas located in the north and south parts of the Iran, in the present study an analysis of the coastal zone behaviour is made. Bed level elevations are measured and compared with the theoretical equilibrium profile. It is shown that the behaviour of the coastal zone in the region is consistent with the Dean (1991) equilibrium profile. In the next stage, following extensive investigations, the bed level changes due to arise in sea level at different locations in the surf zone are estimated. The mechanism of beach re-treatment due to a rise in sea level is considered based on the simplified model of Dean (1991) in which the mass balance of the sediments is taken into account. Comparison of the equilibrium profiles for different cases of sea level rise, clearly shows that because of the sediment transport induced by the fluctuation of the water level, the beach profile in the surf zone changes accordingly resulting in an erosion in the inner region of the surf zone and an accumulation of sediments towards the offshore.

关键词： wave     coastal zone     beach morphology     evolution     equilibrium profile     sea level rise    

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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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Investigation of sediment transport pattern and beach morphology in the vicinity of submerged groyne

H. Afsoos Biria,M. A. Lashteh Neshaei,A. Ghabraei,M. A. Mehrdad

《结构与土木工程前沿（英文）》 2015年 第9卷 第1期   页码 82-90 doi: 10.1007/s11709-014-0275-5

摘要： Marine structures, such as Groynes, Sea walls and Detached Breakwaters, are constructed in coast of area to improve coast stability against bed erosions due to changing wave and current pattern. Marine mechanisms and interaction with the hydraulic structures need to be intensively studied. Groynes are one of the most prominent structures that are used in shore protection and littoral sediment. The main hydraulic function of the groyne is to control the long shore current and littoral sediment transport. This structure can be submerged and provide the necessary beach protection without negative aesthetic impact. However, for submerged structures adopted for beach protection, the shoreline response to these structures is not well understood. The objective of this study is to predict sediment transport in the vicinity of submerged groyne and comparison with non-submerged groyne focusing on a part of the coast at Dahane Sar Sefidrood, Guilan Province, Iran, where serious coast erosion has been occurred. The simulations were designed using a one-line model which can be used as a first approximation of shoreline prediction in the vicinity of groyne. The results of the proposed model are compared with experimental data to determine the shape of the coast. The results of predicted beach deformation show that when submerged groyne construct in the beach, sediment accumulation will be slightly less than the non-submerged groyne; because transfer coefficient for the submerged groyne is more than non-submerged groyne. This result will cause more sediment passing on submerged groyne. Finally, the result of the present study show that using submerged groyne is an efficient way to control the sediment and beach erosion without causing severe environmental effect on the coast.

关键词： submerged groyne     non-submerged groyne     beach morphology     Dahane Sar Sefidrood     sediment transport    

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川东北元坝地区长兴组大型生物礁滩体岩性气藏储层精细刻画技术及勘探实效分析

蔡希源

《中国工程科学》 2011年 第13卷 第10期   页码 28-33

摘要：

以井-震精确标定为基础，借助地质-地球物理建模技术，建立了长兴组生物礁滩体岩性相—测井相—地震相—属性相—储层相（沉积微相）之间精确对应关系。在此基础上，利用地震敏感属性提取及反演方法，精细刻画了礁滩体沉积微相空间展布形态，并结合伽马测井约束的波阻抗孔隙度反演技术对礁滩体储层物性空间分布进行预测。通过与已有钻孔比对，发现储层预测效果不仅与勘探实际相吻合，且具有较高的预测精度。由此认为，地质与地球物理互动反馈的储层预测方法不仅对元坝地区生物礁滩气藏勘探具有理论性指导意义，而且对其他地区礁滩隐蔽油气藏的勘探具有实际性借鉴意义。

关键词： 元坝地区     长兴组     礁滩体     储层预测    

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Water pumping analysis and experimental validation of beach well infiltration intake system in a seawater

Huan ZHANG,Shu LIU,Xuejing ZHENG,Gaofeng CHEN

《能源前沿（英文）》 2015年 第9卷 第3期   页码 335-342 doi: 10.1007/s11708-015-0365-7

摘要： Based on energy conservation equation and Darcy’s law, a model of beach well infiltration intake system applied in a seawater source heat pump system was established. The model consists of the seawater seepage and the heat transfer process. A porous medium model in a software named FLUENT was applied to simulate the seepage and the heat transfer process. This model was also validated by field experiment conducted on the seashore in Tianjin, China. The maximum relative error between simulation results and experimental results was 2.1% (less than 5%), which was acceptable in engineering application. The porosity and coefficient of thermal conductivity of the aquifer soil were determined to be 0.49 W/(m·K) and 1.46 W/(m·K), respectively in the simulation. In addition, the influencing factors of pumping water of beach well were also analyzed. The pumping water was found to increase when the distance between the beach well and the impervious boundary becomes longer, when the distance between the beach well and the supplying water source shortens, when the diameter of the beach well enlarges, and the drawdown enlarges.

关键词： water pumping analysis     experimental validation     infiltration intake system     seawater source heat pump    

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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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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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Tuned reactive power dispatch through modified differential evolution technique

S. BISWAS (RAHA), N. CHAKRABORTY

《能源前沿（英文）》 2012年 第6卷 第2期   页码 138-147 doi: 10.1007/s11708-012-0188-8

摘要： This paper explores the capability of modified differential evolution (MDE) technique for solving the reactive power dispatch (RPD) problem. The proposed method is based on the basic differential evolution (DE) technique with a few modifications made into it. DE is one of the strongest optimization techniques though it suffers from the problem of slow convergence while global minima appear. The proposed modifications are tried to resolve the problem. The RPD problem mainly defines loss minimization with stable voltage profile. To solve the RPD problem, the generator bus voltage, transformer tap setting and shunt capacitor placements are controlled by the MDE approach. In this paper, IEEE 14-bus and IEEE 30-bus systems are chosen for MDE implementation. The applied modification show much improved result in comparison to normal DE technique. Comparative study with other soft-computing technique including DE validates the effectiveness of the proposed method.

关键词： reactive power dispatch (RPD)     modified differential evolution (MDE)     differential evolution algorithm with localizations around the best vector (DELB)    

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标题 作者 时间 类型 操作

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

The effect of sea level rise on beach morphology of caspian sea coast

M. A. Lashteh NESHAEI, F. GHANBARPOUR

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

Investigation of sediment transport pattern and beach morphology in the vicinity of submerged groyne

H. Afsoos Biria,M. A. Lashteh Neshaei,A. Ghabraei,M. A. Mehrdad

期刊论文

川东北元坝地区长兴组大型生物礁滩体岩性气藏储层精细刻画技术及勘探实效分析

蔡希源

期刊论文

Water pumping analysis and experimental validation of beach well infiltration intake system in a seawater

Huan ZHANG,Shu LIU,Xuejing ZHENG,Gaofeng CHEN

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

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

Wenli CHEN, Hui LI,

期刊论文

Tuned reactive power dispatch through modified differential evolution technique

S. BISWAS (RAHA), N. CHAKRABORTY

期刊论文