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Analysis on damage causes of built-in corridor in core rock-fill dam on thick overburden:A case study

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Frontiers of Structural and Civil Engineering 2022年第6期16卷 762-780页

作者： Jia’ao yu Zhenzhong SHEN Zhangxin HUANG College of Water Conservancy and Hydropower Engineering Hohai UniversityNanjing 210024China State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai UniversityNanjing 210024China

The stress state of the built-in corridor in core rock-fill dam on thick overburden is extremely complex,which may produce cracking and *** purpose of this paper was to investigate the effect of thick overburden on the stress and deformation of the built-in corridor in a rock-fill dam,and ascertain the damage causes of the *** rationality of the analysis method for corridor with similar structure is another *** approach is based on finiteelement method and the calculation result accuracy is verified by the field monitoring *** improved analysis method for corridors with similar structure is proposed by comparing various corridor load calculation methods and concrete constitutive *** demonstrate that the damage causes of the corridor are the deformability difference between the overburden and concrete and the special structural *** the calculation model considering dam construction process,contact between concrete and surrounding soil,and concrete damage plasticity can reasonably reflect the mechanical behavior of the *** research conclusions may have a reference significance for the analysis of tunnels similar to built-in corridors.

关键词： thick overburden built-in corridor stress deformation causes for damage concrete damaged plasticity

Optimization design of anti-seismic engineering measures for intake tower based on non-dominated sorting genetic algorithm-Ⅱ

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Frontiers of Structural and Civil Engineering 2023年第9期17卷 1428-1441页

作者： Jia’ao yu Zhenzhong SHEN Zhangxin HUANG Haoxuan LI State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai UniversityNanjing 210024China College of Water Conservancy and Hydropower Engineering Hohai UniversityNanjing 210024China

High-rise intake towers in high-intensity seismic areas are prone to structural safety problems under ***,effective and low-cost anti-seismic engineering measures must be designed for *** intake tower in northwest China was considered the research object,and its natural vibration characteristics and dynamic response were first analyzed using the mode decomposition response spectrum method based on a three-dimensional finite element *** non-dominated sorting genetic algorithm-II(NSGA-II)was adopted to optimize the anti-seismic scheme combination by comprehensively considering the dynamic tower response and variable project ***,the rationality of the original intake tower antiseismic design scheme was evaluated according to the obtained optimal solution set,and recommendations for improvement were *** method adopted in this study may provide significant references for designing anti-seismic measures for high-rise structures such as intake towers located in high-intensity earthquake areas.

关键词： intake tower NSGA-II mode decomposition response spectrum method anti-seismic engineering measures optimization design variable project cost

Discussion on the mechanism of the calcium absorption in the human body

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Chinese Science Bulletin 2001年第16期46卷 1403-1408页

作者： ZHANG Jingkun ZHANG Zemin yu ao Central Laboratory Nankai UniversityTianjin 300071China Department of Chemistry Nankai UniversityTianjin 300071China

The present article discusses a new mechanism of calcium absorption in the human body. The mechanism is revealed as follows. First, after food is digested in the stomach, calcium ions (Ca2+) are released. The small intestine secretes amino acid or short peptide chain with small molecular weight automatically, which are called chelating agent; when the calcium ions from the stomach get to the small intestine, the reaction of the chelating agent with the calcium ions occurs, producing the neutral amino acid calcium chelate. Then, this kind of calcium chelate with small molecular weight is absorbed as a whole into the tissues of the small intestine. After being absorbed, in the cell the calcium chelate can break down its chelating bond automatically and decompose into the amino acid and calcium ion again. Finally, the calcium ion goes into blood through portal vein and is transferred to the organs and also deposits on the bone. The reason for the body抯 calcium insufficiency, which has no linear relation with the calcium intake amount, is the lack of the amino acid secreted by the small intestine. The main barrier that influences the calcium absorption is anion pollution. The calcium absorptivity of the body has nothing to do with the solubility of the calcium source out of the body. A new kind of calcium supplement agent——glycine calcium chelate——is synthesized, whose molecular weight is 206.06 (containing a molecular water). If the glycine calcium chelate is used to make calcium supplement agent, about 20 mg calcium element (converted from the glycine calcium chelate, the same below, no longer indicated) per day for one person, 50 mg at most, is enough to maintain the positive balance of calcium metabolism.

关键词： amino acid chelate calcium.

An artificial intelligence-aided design (AIAD) of ship hull structures

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Journal of Ocean Engineering and Science 2023年第1期8卷 15-32页

作者： yu ao yunbo Li Jiaye Gong Shaofan Li College Of Shipbuilding Engineering Harbin Engineering UniversityChina Department of Civil and Environmental Engineering University of CaliforniaBerkeleyCA 94720USA College of Ocean Science and Engineering Shanghai Maritime UniversityChina

Ship-hull design is a complex process because the any slight local alteration in ship hull structure may significantly change the hydrostatic and hydrodynamic performances of a *** find the optimum hull shape under the design requirements,the state-of-art of ship hull design combines computational fluid dynamics computation with geometric ***,this process is very computationally intensive,which is only suitable at the final stage of the design *** narrow down the design parameter space,in this work,we have developed an AI-based deep learning neural network to realize a real-time prediction of the total resistance of the ship-hull structure in its initial design *** this work,we have demonstrated how to use the developed DNN model to carry out the initial ship hull *** validation results showed that the deep learning model could accurately predict the ship hull’s total resistance accurately after being trained,where the average error of all samples in the testing dataset is lower than 4%.Simultaneously,the trained deep learning model can predict the hip’s performances in real-time by inputting geometric modification parameters without tedious preprocessing and calculation *** machine learning approach in ship hull design proposed in this work is the first step towards the artificial intelligence-aided design in naval architectures.

关键词： Artificial intelligence Deep learning neural network Hull deformation Machine learning Ship hull design Total resistance

An adaptive machine learning-based optimization method in the aerodynamic analysis of a finite wing under various cruise conditions

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Theoretical & Applied Mechanics Letters 2024年第1期14卷 27-34页

作者： Zilan Zhang yu ao Shaofan Li Grace X.Gu Department of Mechanical Engineering University of CaliforniaBerkeley 94720USA Department of Engineering Peking UniversityBeijing 100871China Department of Civil and Environmental Engineering University of CaliforniaBerkeley 94720USA

Conventional wing aerodynamic optimization processes can be time-consuming and imprecise due to the complexity of versatile flight *** of existing literature has considered two-dimensional infinite airfoil optimization,while three-dimensional finite wing optimizations are subject to limited study because of high computational *** we create an adaptive optimization methodology built upon digitized wing shape deformation and deep learning algorithms,which enable the rapid formulation of finite wing designs for specific aerodynamic performance demands under different cruise *** methodology unfolds in three stages:radial basis function interpolated wing generation,collection of inputs from computational fluid dynamics simulations,and deep neural network that constructs the surrogate model for the optimal wing *** has been demonstrated that the proposed methodology can significantly reduce the computational cost of numerical *** also has the potential to optimize various aerial vehicles undergoing different mission environments,loading conditions,and safety requirements.

关键词： Aerodynamic optimization Computational fluid dynamics Radial basis function Finite wing Deep learning neural network

The foxtail millet Si69 gene is a Wali7 (wheat aluminum-induced protein 7) homologue and may function in aluminum tolerance

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Chinese Science Bulletin 2009年第10期54卷 1697-1706页

作者： ZHao LinNa ZHao Qian ao GuangMing yu JingJuan State Key Laboratory for Agro-Biotechnology College of Biological Sciences China Agricultural University Beijing 100193 China

We isolated a clone, named Si69, from a foxtail millet immature seed cDNA library. The protein encoded by Si69 contains a conserved Wali7 (wheat aluminum induced protein 7) domain and shares high-level homology with aluminum-induced proteins from other species including rice and Arabidopsis. The Si69 gene presents as a single locus in foxtail millet genome and is globally expressed in all tissues examined. Its expression is up-regulated by aluminum. The sequence feature and expression pattern suggest that the Si69 gene is involved in aluminum tolerance or detoxification. To confirm its biological functions, Si69 controlled by the CaMV35S promoter was introduced into Arabidopsis. Transgenic plants did not show any visible morphological changes compared to wild-type plants under normal growth conditions. However, when treated with 20 or 50 μmol/L Aluminum (Al), the root apices of wild-type plants were heavily stained by hematoxylin, whereas those of Si69 transgenic plants were not stained when treated with 20 μmol/L Al and slightly stained when treated with 50 μmol/L Al. Scanning electron microscopy (SEM) results further demonstrated that the damage of the root apices was se- verer in wild-type plants than in transgenic plants. Inhibition of root growth and accumulation of malondialdehyde (MDA), an indicator of lipid peroxidation, were lower in transgenic plants than in wild-type plants. The results show that overexpression of Si69 may increase Al tolerance in transgenic plants, indicating that a series of Wali7-containing genes may play similar roles in Al tolerance/detoxification.

关键词： Si69 诱导蛋白耐铝性基因组同源性谷子小麦转基因植物

Double dehydrogenation of carbocyclic β-dicarbonyl compounds:Koser's reagent can do what iodine(V) reagents can

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Science China Chemistry 2019年第5期62卷 597-601页

作者： Shan-Shan Liu Li Wang Ya-Nan Duan ao yu Chi Zhang State Key Laboratory of Elemento-Organic Chemistry Collaborative Innovation Center of Chemical Science and Engineering (Tianjin)College of ChemistryNankai University Department of Chemical Engineering and Safety Binzhou University Central Laboratory College of ChemistryNankai University

Koser's reagent is found to be effective in the oxidative double dehydrogenation of various carbocyclic β-dicarbonyl compounds,which constitutes the first example on dehydrogenation reactivity of hypervalent iodine(Ⅲ) reagents for carbocyclic carbonyl compounds. DFT calculations reveal that the rate-determining step is the electrophilic addition of PhI+OH onto enolate of monodehydrogenated product.

关键词： Koser’s reagent double dehydrogenation hypervalent twisting 2,3-benzotropone DFT calculations

Optimal Virtual Battery Model for Aggregating Storage-Like Resources with Network Constraints

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CSEE Journal of Power and Energy Systems 2024年第4期10卷 1843-1847页

作者： Zhenfei Tan ao yu Haiwang Zhong Xianfeng Zhang Qing Xia Chongqing Kang Department of Electrical Engineering and Sichuan Energy Internet Research Institute Tsinghua UniversityBeijing 100084China Science and Technology Institute of China Three Gorges Corporation Hubei 430010China

A virtual battery(VB)provides a succinct interface for aggregating distributed storage-like resources(SLR)to interact with a utility-level *** overcome the drawbacks of existing VB models,including conservatism and neglecting network constraints,this paper optimizes the power and energy parameters of VB to enlarge its flexibility *** optimal VB is identified by a robust optimization problem with decision-dependent *** algorithm based on the Benders decomposition is developed to solve this *** proposed method yields the largest VB satisfying constraints of both network and *** studies verify the superiority of the optimal VB in terms of security guarantee and less conservatism.

关键词： Aggregation decision-dependent uncertainty flexibility robust optimization virtual battery

Blockchain-Based Secure Distributed Control for Software Defined Optical Networking

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China Communications 2019年第6期16卷 42-54页

作者： Hui Yang Yongshen Liang Qiuyan Yao Shaoyong Guo ao yu Jie Zhang State Key Laboratory of Information Photonics and Optical Communications Beijing University of Posts and TelecommunicationsBeijing 100876China State Key Laboratory of Networking and Switch Technology Beijing University of Posts and TelecommunicationsBeijing 100876China

Software defined optical networking(SDON)is a critical technology for the next generation network with the advantages of programmable control and *** one of the key issues of SDON,the security of control plane has also received extensive attention,especially in certain network scenarios with high security *** to the existence of vulnerabilities and heavy overhead,the existing firewalls and distributed control technologies cannot solve the control plane security problem *** this paper,we propose a distributed control architecture for SDON using the blockchain technique(BlockCtrl).The proposed BlockCtrl model introduces the advantages of blockchain into SDON to achieve a high-efficiency fault tolerant *** have evaluated the performance of our proposed architecture and compared it to the existing models with respect to various metrics including processing rate,recovery latency and *** numerical results show that the BlockCtrl is capable of attacks detection and fault tolerant control in SDON with high performance on resource utilization and service correlation.

关键词： blockchain fault tolerant control network security software defined networking