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Modified Multifidelity Surrogate Model Based on Radial Basis Function with Adaptive Scale Factor

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Chinese Journal of Mechanical Engineering 2022年第4期35卷 109-123页

作者： yin liu Shuo Wang Qi Zhou Liye Lv Wei Sun Xueguan Song School of Mechanical Engineering Dalian University of Technology School of Aerospace Engineering Huazhong University of Science and Technology School of Mechanical Engineering and Automation Zhejiang Sci-Tech University

Multifidelity surrogates(MFSs) replace computationally intensive models by synergistically combining information from different fidelity data with a significant improvement in modeling efficiency. In this paper, a modified MFS(MMFS) model based on a radial basis function(RBF) is proposed, in which two fidelities of information can be analyzed by adaptively obtaining the scale factor. In the MMFS, an RBF was employed to establish the low-fidelity *** correlation matrix of the high-fidelity samples and corresponding low-fidelity responses were integrated into an expansion matrix to determine the scaling function parameters. The shape parameters of the basis function were optimized by minimizing the leave-one-out cross-validation error of the high-fidelity sample points. The performance of the MMFS was compared with those of other MFS models(MFS-RBF and cooperative RBF) and single-fidelity RBF using four benchmark test functions, by which the impacts of different high-fidelity sample sizes on the prediction accuracy were also analyzed. The sensitivity of the MMFS model to the randomness of the design of experiments(DoE) was investigated by repeating sampling plans with 20 different DoEs. Stress analysis of the steel plate is presented to highlight the prediction ability of the proposed MMFS model. This research proposes a new multifidelity modeling method that can fully use two fidelity sample sets, rapidly calculate model parameters, and exhibit good prediction accuracy and robustness.

关键词： Multi-fidelity surrogate RBF Adaptive scaling factor LOOCV Expansion matrix

Distributed hydrological models for addressing effects of spatial variability of roughness on overland flow

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Water Science and Engineering 2016年第3期9卷 249-255页

作者： Sheng-tang Zhang yin liu Miao-miao Li Bo Liang College of Earth Science and Engineering Shandong University of Science and Technology College of Mining and Safety Engineering Shandong University of Science and Technology

In this study, we investigated the origin of the overland flow roughness problem and divided the current overland flow roughness research into three types, as follows: the first type of research takes into account the effects of roughness on the volume and velocity of surface runoff, flood peaks, and the scouring capability of flows, but has not addressed the spatial variability of roughness in detail; the second type of research considers that surface roughness varies spatially with different land usage types, land-cover conditions, and different tillage forms, but lacks a quantitative study of the spatial variability; and the third type of research simply deals with the spatial variability of roughness in each grid cell or land type. We present three shortcomings of the current overland flow roughness research, including(1) the neglect of roughness in distributed hydrological models when simulating the overland flow direction and distribution,(2) the lack of consideration of spatial variability of roughness in hydrological models, and(3) the failure to distinguish the roughness formulas in different overland flow regimes. To solve these problems,distributed hydrological model research should focus on four aspects in regard to overland flow: velocity field observations, flow regime mechanisms, a basic roughness theory, and scale problems.

关键词： Distributed hydrological model Overland flow Roughness Spatial variability

Model Reduction Methods for High-Rise Buildings with Active Mass Damper Control Systems

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Journal of Harbin Institute of Technology(New Series) 2013年第6期20卷 37-45页

作者： Jun Teng Hou-Bing Xing Cheng-yin liu Shenzhen Key Lab of Urban & Civil Engineering Disaster Prevention & Reduction Harbin Institute of Technology Shenzhen Graduate School

To improve the performance of an active mass damper control system,the controller should be designed based on a reduced-order model. An improved method based on balanced truncation method was proposed to reduce the dimension of high-rise buildings,and was compared with other widely used reduction methods by using a framework with ten floors. This optimized method has improvement of reduction process and choice of the order. Based on the reduced-order model obtained by the improved method and pole-assignment algorithm,a controller was designed. Finally,a comparative analysis of structural responses,transfer functions,and poles was conducted on an actual high-rise building. The results show the effectiveness of the improved method.

关键词： high-rise building active mass damper model reduction controller designCLC number:TU352 Document code:AArticle ID:1005-9113(2013)06-0037-09

Prediction model for flow stress during isothermal compression in α+β phase field of TC4 alloy

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Rare Metals 2018年第5期37卷 369-375页

作者： Shun Yang Hong Li Jiao Luo yin-Gang liu Miao-Quan Li School of Materials Science and Engineering Northwestern Polytechnical University

Isothermal compression of TC4 alloy was performed on a Thermecmaster-Z simulator at the deformation temperatures ranging from 1093 to 1243 K, the strain rates ranging from 0.001 to 10.000 s^-l and a maximum strain of 0.8. The experimental results show that the flow stress increases with the decrease in the deformation temperature and the increase in the strain rate. The apparent activation energy for deformation is much lower at lower strain rates than that at higher strain rates. The flow stress model considering strain compensation was established. The average relative error between the calculated flow stress and experimental results is about 7.69%, indicating that the present model could be used to accurately predict the flow stress during high temperature in α＋β phase field of TC4 alloy.

关键词： TC4 alloy Isothermal compression Model Flow stress

The application of CRISPR-Cas in disease diagnosis and treatment

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Science China Chemistry 2023年第10期66卷 2734-2742页

作者： Zhiying Wang yin liu Fuling Zhou Yafen Wang Xiang Zhou School of Public Health Wuhan UniversityWuhan 430071China College of Chemistry and Molecular Sciences Wuhan UniversityWuhan 430072China Taikang Center for Life and Medical Sciences Wuhan UniversityWuhan 430071China Cross Research Institute of Zhongnan Hospital Wuhan UniversityWuhan 430071China Department of Hematology of Zhongnan Hospital Wuhan UniversityWuhan 430071China Department of Chemistry College of SciencesHuazhong Agricultural UniversityWuhan 430070China

Clustered regularly interspaced short palindromic repeat(CRISPR)has been gaining much attention in the modern medical field and has been widely used for the diagnosis and treatment of diseases in recent *** this review,we will introduce the application of CRISPR in disease diagnosis and treatment,including its use in detecting pathogens,gene mutations,and genetic diseases,as well as its application in gene therapy for single-gene diseases,cancer,viral infectious diseases,and cardiovascular ***,we will discuss the potential future directions and challenges of CRISPR in the diagnosis and treatment of diseases,and provide a thorough overview of the ways in which CRISPR is used for diagnosing and treating diseases.

关键词： CRISPR application disease diagnosis disease treatment

Structural characteristics and implication on tectonic evolution of the Daerbute strike-slip fault in West Junggar area, NW China

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Frontiers of Earth Science 2018年第3期12卷 555-568页

作者： Kongyou WU Yangwen PEI Tianran LI Xulong WANG yin liu Bo liu Chao MA School of Geosciences China University of Petroleum Qingdao 266580 China Laboratory for Marine Mineral Resources Qingdao National Laboratory for Marine Science and Technology Qingdao 266071 China Key Laboratory of Tectonics and Petroleum Resources (China University of Geosciences) Ministry of Education Wuhan 430074 China Xinjiang Oilfield Company PetroChina Karamay 834000 China

The Daerbute fault zone, located in the northwestern margin of the Junggar basin, in the Central Asian Orogenic Belt, is a regional strike-slip fault with a length of 400 km. The NE-SW trending Daerbute fault zone presents a distinct linear trend in plain view, cutting through both the Zair Mountain and the Hala＇alate Mountain. Because of the intense contraction and shearing, the rocks within the fault zone experienced high degree of cataclasis, schistosity, and mylonization, resulting in rocks that are easily eroded to form a valley with a width of 300- 500 m and a depth of 50-100 m after weathering and erosion. The well-exposed outcrops along the Daerbute fault zone present sub-horizontal striations and sub-vertical fault steps, indicating sub-horizontal shearing along the observed fault planes. Flower structures and horizontal drag folds are also observed in both the well-exposed outcrops and high-resolution satellite images. The distribution of accommodating strike-slip splay faults, e.g., the 973-pluton fault and the Great Jurassic Trough fault, are in accordance with the Riedel model of simple shear. The seismic and time-frequency electromagnetic （TFEM） sections also demonstrate the typical strike-slip characteristics of the Daerbute fault zone. Based on detailed field observations of well-exposed outcrops and seismic sections, the Daerbute fault can be subdivided into two segments： the western segment presents multiple fault cores and damage zones, whereas the eastern segment only presents a single fault core, in which the rocks experienced a higher degree of rock cataclasis, schistosity, and mylonization. In the central overlapping portion between the two segments, the sediments within the fault zone are primarily reddish sandstones, conglomerates, and some mudstones, of which the palynological tests suggest middle Permian as the timing of deposition. The deformation timing of the Daerbute fault was estimated by integrating the depocenters＇ basinward migrat

关键词： Daerbute fault structural characteristics deformation timing West Junggar

Immediate implantation of ultrafine fiber slow-release system based on cell electrospinning to induce osteogenesis of mesenchymal stem cells

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Regenerative Biomaterials 2024年第2期3卷 76-87页

作者： Tao Lu Long Yang Zhuoyang Li yin liu Shun'en Xu Chuan Ye Department of Orthopaedics The Affliated Hospital of Guizhou Medical UniversityGuiyang 550004China Department of Orthopaedics The First People's Hospital of GuiyangGuiyang 550004China Center for Tissue Engineering and Stem Cell Research Guizhou Medical UniversityGuiyang 550004China Department of Otolaryngology Head and Neck Surgery Xinqiao HospitalArmy Medical University(Third Military Medical University)Chongqing 400037China Department of Dental implant Stomatological Hospital of GuiyangGuiyang 550000China

This study presents the development and evaluation of a poly(3-hydroxybutyrate-co-4-hydroxybutyrate)(P34HB)ultrafine fiber slow-release system for in vivo osteogenic induction of human umbilical cord mesenchymal stem cells(HUCMSCs).Utilizing dual-nozzle and cell electrospinning techniques,the system encapsulates L-ascorbic acid-2-phosphate magnesium(AsP),βB-glycerophosphate sodium and dexamethasone(DEX)within the'fbers,ensuring sustained osteogenic *** scaffold's morphology,characterization,hydrophilicity,mechanical properties and cellular behavior were *** subcutaneous implantation in rabbits was con-ducted to observe its ectopic osteogenic induction *** fabricated P34HB ultrafine fiber slow-release *** ization *** distribution of HUCMSCs and inducing components within the scaffold,with no chemical reactions affecting the active *** vitro tests showcased a prolonged release of DEX and ASP,while biocompatibility assays highlighted the scaffold's suitability for cellular *** Red,type I collagen,and osteopontin(OPN)staining verifed the scaffold's potent osteogenic induction effect on ***,immediate implantation into New Zealand White rabbits led to significant new bone formation within 8 *** findings underscore the system's potential for immediate in vivo implantation without prior in vitro induction,marking a promising advancement in bone tissue engineering.

关键词： bone tissue engineering cell electrospinning in vivo induction immediate implantation biomaterials

Detection of Ultra Trace Amount Gossypol with Chemiluminescence Using Capillary Electrophoresis as Injection Techniques

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Chinese Chemical Letters 2005年第12期16卷 1649-1651页

作者： Er Bao liu Min ZHANG Bing Chun XUE Peng Xiang ZHAO yin liu School of Chemistry and Life Sciences Tianjin Normal University Tianjin 300074

Detection of ultra trace amount gossypol is reported. It is based on luminolhexacyanoferrate（Ⅲ） chemiluminescence reaction with gossypol as a sensitizer. The detection limit （3 σ ）of gossypol reaches 5.21 × 10^... 详细信息

关键词： Capillary electrophoresis chemiluminescence gossypol

Separation of rhenium from electric-oxidation leaching solution of molybdenite

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Journal of Central South University 2013年第8期20卷 2103-2108页

作者： CAO Zhan-fang ZHONG Hong JIANG Tao liu Guang-yi WANG Shuai XIA liu-yin College of Chemistry and Chemical Engineering Central South University Changsha 410083 China Key Laboratory of Resources Chemistry of Nonferrous Metals of Ministry of Education (Central South University) Changsha 410083 China School of Minerals Processing & Bioengineering Central South University Changsha 410083 China

The separation of rhenium from molybdenum in aqueous solution has always been a problem in hydrometallurgy. The separation of rhenium from the electro-oxidation leachate of molybdenite and its mechanism were investigated. The results show that pH of the leachate significantly affects adsorption rate compared with other experimental parameters. When temperature is 30℃, pH=8, and adsorbing time is 1 h, adsorption rates of rhenium and molybdenum are 93.46% and 3.57%, respectively, and separation factor of D301 resin for rhenium and molybdenum is 169.56. In addition, the separation factor is higher when the initial molybdenum concentration in model solution is increased. The saturated adsorption capacity of D301 resin for molybdenum and rhenium calculated based on simulated results are 4.263 3 mmol/g and 4.235 5 mmol/g, respectively. D301 resin is an effective separation material of rhenium from electric-oxidation leachate of molybdenite. The adsorption kinetics results also show that the adsorption of rhenium is easier than that of molybdenum, and the adsorption process of D301 for rhenium and molybdenum may be controlled by liquid film diffusion.

关键词： rhenium molybdenum separation resin molybdenite