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Least Square Finite Element Method for Viscous Splitting of Unsteady Incompressible Navier–Stokes Equations

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China Ocean Engineering 2018年第4期32卷 490-500页

作者： SHUI Qing-xiang WANG Da-guo he zhi-liang HUANG Jin School of Human Settlement and Civil Engineering Xi'an Jiaotong University School of Environmental and Resources Southwest University of Science and Technology

In order to solve unsteady incompressible Navier–Stokes(N–S) equations, a new stabilized finite element method,called the viscous-splitting least square FEM, is proposed. In the model, the N–S equations are split into diffusive and convective parts in each time step. The diffusive part is discretized by the backward difference method in time and discretized by the standard Galerkin method in space. The convective part is a first-order nonlinear *** the linearization of the nonlinear part by Newton’s method, the convective part is also discretized by the backward difference method in time and discretized by least square scheme in space. C0-type element can be used for interpolation of the velocity and pressure in the present model. Driven cavity flow and flow past a circular cylinder are conducted to validate the present model. Numerical results agree with previous numerical results, and the model has high accuracy and can be used to simulate problems with complex geometry.

关键词： unsteady incompressible N–S equations viscous splitting Newton's method least square finite element method driven cavity flow flow past a circular cylinder

Dual influence of the rejuvenation of Southern Tianshan and Western Kunlun orogen on the Cenozoic structure deformation of Tarim Basin,northwestern China:A superposition deformation model from Bachu Uplift

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第9期8卷 1388-1394页

作者： he Guang-yu he zhi-liang ZHANG Hong-an ZHU zhi-xin CheN Qiang-lu QIAN Yi-xiong GU Yi Department of Earth Sciences Structure Research Center of Petroleum Basin of China Education Ministry Zhejiang University Hangzhou 310027 China Exploration and Production Research Institute SINOPEC Beijing 100083 China Westeastern Branch of Exploration and Production Research Institute SINOPEC Urumqi 830011 China Wuxi Research Institute of Petroleum and Experiment Geology SINOPEC Wuxi 214214 China

Based on new high-resolution seismic profiles and existing structural and sedimentary results, a superposition deformation model for Cenozoic Bachu Uplift of northwestern Tarim Basin, northwestern China is proposed. The model presents the idea that the Bachu Uplift suffered structure superposition deformation under the dual influences of the Cenozoic uplifting of Southern Tianshan and Western Kunlun orogen, northwestern China. In the end of the Eocene （early Himalayan movement）, Bachu Uplift started to be formed with the uplifting of Western Kunlun, and extended NNW into the interior of Kalpin Uplift. In the end of the Miocene （middle Himalayan movement）, Bachu Uplift suffered not only the NNW structure deformation caused by the Western Kunlun uplifting, but also the NE structure deformation caused by the Southern Tianshan uplifting, and the thrust front fault of Kalpin thrust system related to the Southern Tianshan orogen intrudes southeastward into the hinterland of Bachu Uplift and extends NNE from well Pil to Xiaohaizi reservoir and Gudongshan mountain, which resulted in the strata folded and denuded strongly. In the end of the Pliocene （late Himalayan movement）, the impact of Southern Yianshan orogen decreased because of the stress released with the breakthrough upward of Kalpin fault extending NE, and Bachu Uplift suffered mainly the structure deformation extending NW-NNW caused by the uplifting of Western Kunlun orogen.

关键词： Superposition deformation model Bachu Uplift Southern Tianshan Western Kunlun Cenozoic

High-Order Two-Scale Asymptotic Paradigm for the Elastodynamic Homogenization of Periodic Composites

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Acta Mechanica Solida Sinica 2024年第1期37卷 124-138页

作者： Wei-zhi Luo Mu he liang Xia Qi-Chang he State Key Laboratory of Intelligent Manufacturing Equipment and Technology Huazhong University of Science and TechnologyWuhan 430074China Laboratoire Modélisation et Simulation Multi-Echelle MSME UMR 8208 CNRSUniversite Gustave Eiffel77454 Marne-la-ValléeFrance

The classical two-scale asymptotic paradigm provides macroscopic and microscopic analyses for the elastodynamic homogenization of periodic composites based on the spatial or/and temporal variable,which offers an approximate framework for the asymptotic homogenization analysis of the motion ***,in this framework,the growing complexity of the homogenization formulation gradually becomes an obstacle as the asymptotic order *** such a context,a compact,fast,and accurate asymptotic paradigm is *** work reviews the high-order spatial two-scale asymptotic paradigm with the effective displacement field representation and optimizes the implementation by symmetrizing the tensor to be ***,the modified implementation gets rid of the excessive memory consumption required for computing the high-order tensor,which is demonstrated by representative one-and two-dimensional *** numerical results show that(1)the contrast of the material parameters between media in composites directly affects the convergence rate of the asymptotic results for the homogenization of periodic composites,(2)the convergence error of the asymptotic results mainly comes from the truncation error of the modified asymptotic homogenized motion equation,and(3)the excessive norm of the normalized wavenumber vector in the two-dimensional inclusion case may lead to a non-convergence of the asymptotic results.

关键词： Composites Homogenization Asymptotic analysis Dynamics Dispersion

Effects of cyhalothrin on the transient outward potassium current in central neurons of helicoverpa armigera

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Insect Science 2006年第1期13卷 13-17页

作者： YONG WANG BING-JUN he QIANG ZHAO zhi liang AN-XI LIU College of Life Science Nankai Univerity Tianjin China

The effects of cyhalothrin on the transient outward potassium current in central neurons of helicoverpa armigera were studied by using the patch clamp techniques. The results showed that before using cyhalothrin （10.5 mmol/L）, activation potential was approximately -40 mV, after application of the drug, the activation potential shifted roughly 10 mV to the negative potential direction, so channels can be activated more easily. Before and after cyhalothrin application, the change of current amplitude was insignificant. The value of V1/2 and k of activation curves did not change significantly, however, the V1/2 of the inactivation curves changed significantly. Inactivation curves significantly shifted to a negative direction, so that inactivation of the channels was hastened. It is indicated that there may exit a primary way in which cyhalothrin provides neurotoxicity to the nervous system through the regulation of activation potentials and inactivation state of IA channels.

关键词： cyhalothrin helicoverpa armigera patch clamp potassium channel

AAV for Gene Therapy in Ocular Diseases:Progress and Prospects

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Research 2024年第3期2023卷 651-670页

作者： Xiaoyu he Yidian Fu liang Ma Yizheng Yao Shengfang Ge zhi Yang Xianqun Fan Department of Ophthalmology Ninth People’s HospitalShanghai JiaoTong University School of MedicineShanghaiChina Shanghai Key Laboratory of Orbital Diseases and Ocular Oncology ShanghaiChina Jiangsu Key Laboratory of Neuropsychiatric Diseases and Institute of Neuroscience Soochow UniversityClinical Research Center of Neurological DiseaseThe Second Affiliated Hospital of Soochow UniversitySuzhouChina

Owing to the promising therapeutic effect and one-time treatment advantage, gene therapy may completely change the management of eye diseases, especially retinal diseases. Adeno-associated virus (AAV) is considered one of the most promising viral gene delivery tools because it can infect various types of tissues and is considered as a relatively safe gene delivery vector. The eye is one of the most popular organs for gene therapy, since its limited volume is suitable for small doses of AAV stably transduction. Recently, an increasing number of clinical trials of AAV-mediated gene therapy are underway. This review summarizes the biological functions of AAV and its application in the treatment of various ocular diseases, as well as the characteristics of different AAV delivery routes in clinical applications. here, the latest research progresses in AAV-mediated gene editing and silencing strategies to modify that the genetic ocular diseases are systematically outlined, especially by base editing and prime editing. We discuss the progress of AAV in ocular optogenetic therapy. We also summarize the application of AAV-mediated gene therapy in animal models and the difficulties in its clinical transformation.

关键词： AAV organs treatment

Data-driven Wasserstein distributionally robust chance-constrained optimization for crude oil scheduling under uncertainty

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Chinese Journal of Chemical Engineering 2024年第5期69卷 152-166页

作者： Xin Dai liang Zhao Renchu he Wenli Du Weimin Zhong zhi Li Feng Qian Key Laboratory of Smart Manufacturing in Energy Chemical Process Ministry of EducationEast China University of Science and TechnologyShanghai 200237China Engineering Research Center of Process System Engineering Ministry of EducationEast China University of Science and TechnologyShanghai 200237China

Crude oil scheduling optimization is an effective method to enhance the economic benefits of oil *** uncertainties,including uncertain demands of crude distillation units(CDUs),might make the production plans made by the traditional deterministic optimization models infeasible.A data-driven Wasserstein distributionally robust chance-constrained(WDRCC)optimization approach is proposed in this paper to deal with demand uncertainty in crude oil ***,a new deterministic crude oil scheduling optimization model is developed as the basis of this *** Wasserstein distance is then used to build ambiguity sets from historical data to describe the possible realizations of probability distributions of uncertain demands.A cross-validation method is advanced to choose suitable radii for these ambiguity *** deterministic model is reformulated as a WDRCC optimization model for crude oil scheduling to guarantee the demand constraints hold with a desired high probability even in the worst situation in ambiguity *** proposed WDRCC model is transferred into an equivalent conditional value-at-risk representation and further derived as a mixed-integer nonlinear programming *** case studies from a real-world refinery are conducted to show the effectiveness of the proposed ***-of-sample tests demonstrate that the solution of the WDRCC model is more robust than those of the deterministic model and the chance-constrained model.

关键词： Distributions Model Optimization Crude oil scheduling Wasserstein distance Distributionally robust chance constraints

Discussion on evaluation methodology of hydrothermal geothermal reservoir

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Journal of Groundwater Science and Engineering 2019年第1期7卷 29-41页

作者： FENG Jian-yun ZHANG Ying he zhi-liang SUN Zi-ming LUO Jun Petroleum Exploration and Production Research Institute of Sinopec Sinopec Group Company

Geothermal reservoir are the vehicle of geothermal resources and their occurrence as well as the storage mass. Precise description and evaluation of geothermal reservoir serves to be the cornerstone of geothermal resource exploration and exploitation. Based on the principles and basic train of geothermal reservoir evaluation, in this work, the content of geothermal reservoir evaluation was determined and the value range of geothermal reservoir evaluation parameters was discussed in combination with the actual production data of two types of geothermal reservoir in North China: The Neogene Guantao Formation sandstone pore-type geothermal reservoir, and the CambrianOrdovician and Middle Proterozoic Jixian carbonate karst-fissure-type geothermal reservoir. An evaluation method for the sandstone pore-type and the carbonate karstfissure-type geothermal reservoir is finally established based on the analysis of the production data, i.e. the values of geothermal reservoir temperature, geothermal fluid production, reinjection, physical properties and other parameters are assigned, and the geometric average value of the assigned values for the above-mentioned parameters is taken as the overall evaluation index of geothermal reservoir. From large to small, this index categorizes geothermal reservoir into three grades:Ⅰ, Ⅱ and Ⅲ, which corresponds to advantageous, moderate advantageous and disadvantageous geothermal reservoir respectively. The geothermal reservoir of the same grade are further classified in light of the index value, thus realizing the comprehensive evaluation of geothermal reservoir.

关键词： Evaluation methodology Hydrothermal geothermal Geothermal reservoir

Study of primordial deuterium abundance in Big Bang nucleosynthesis

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Nuclear Science and Techniques 2024年第3期35卷 208-215页

作者： zhi-Lin Shen Jian-Jun he Key Laboratory of Beam Technology of Ministry of Education College of Nuclear Science and TechnologyBeijing Normal UniversityBeijing 100875China Institute of Radiation Technology Beijing Academy of Science and TechnologyBeijing 100875China

Big Bang nucleosynthesis(BBN)theory predicts the primordial abundances of the light elements^(2) H(referred to as deuterium,or D for short),^(3)he,^(4)he,and^(7) Li produced in the early *** these,deuterium,the first nuclide produced by BBN,is a key primordial material for subsequent *** date,the uncertainty in predicted deuterium abundance(D/H)remains larger than the observational *** this study,the Monte Carlo simulation code PRIMAT was used to investigate the sensitivity of 11 important BBN reactions to deuterium *** found that the reaction rate uncertainties of the four reactions d(d,n)^(3)he,d(d,p)t,d(p,γ)^(3)he,and p(n,γ)d had the largest influence on the calculated D/H ***,the calculated D/H uncertainty cannot reach observational precision even with the recent LUNA precise d(p,γ)^(3) he *** the nuclear physics aspect,there is still room to largely reduce the reaction-rate uncertainties;hence,further measurements of the important reactions involved in BBN are still necessary.A photodisintegration experiment will be conducted at the Shanghai Laser Electron Gamma Source Facility to precisely study the deuterium production reaction of p(n,γ)d.

关键词： Big Bang nucleosynthesis Abundance of deuterium Reaction cross section Reaction rate Monte Carlo method

不同强度铒激光荡洗活化对前磨牙根管内壁的清洗效果及根管硬度的影响

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川北医学院学报 2024年第8期39卷 1118-1121页

作者：马慧颖李士辉岳琳曹雷李春佳何志良承德市中心医院口腔科河北承德067000

目的:探究不同强度铒激光(Er:YAG激光)荡洗活化对前磨牙根管内壁的清洗效果及根管硬度的影响。方法:根据铒激光荡洗强度不同将80例重度牙周炎患者拔除的137颗单根前磨牙分成实验A组、实验B组及对照组。A组采用0.2W Er:YAG激光荡洗,共45... 详细信息

目的:探究不同强度铒激光(Er:YAG激光)荡洗活化对前磨牙根管内壁的清洗效果及根管硬度的影响。方法:根据铒激光荡洗强度不同将80例重度牙周炎患者拔除的137颗单根前磨牙分成实验A组、实验B组及对照组。A组采用0.2W Er:YAG激光荡洗,共45颗牙;B组采用0.3W Er:YAG激光荡洗,共42颗;对照组常规注射器头冲洗,共50颗牙。比较组间清洗后牙本质表面清洗效果、根尖渗透情况和根管硬度。结果:与对照组相比,A、B组的渗透距离更小(P0.05)。A组、B组根颈/根中硬度均大于对照组(P0.05)。B组玷污层戈夫曼玷污分级均低于对照组及A组(P<0.05)。结论:相较于常规注射器冲洗,铒激光荡洗活化可有效提高牙周炎前磨牙根管内壁的清洗效果,同时铒激光荡洗活化可减小对根管的损伤。0.3 W铒激光的清洗效果优于0.2 W,不同强度铒激光对根管硬度的影响较小。

关键词：前磨牙患者铒激光荡洗活化清洗效果根管硬度

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