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Application of oblique photogrammetry technique in geological hazard identification and decision management

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Earthquake Research Advances 2024年第3期4卷 34-41页

作者： Min Tang xi mei Yanna Li Chen Chen xiuju liu Heng Lu China Railway Eryuan Engineering Group CO.LTD Chengdu610031China School of Environment and Resource Southwest University of Science and TechnologyMianyang621000China State Key Laboratory of Hydraulics and Mountain River Engineering Sichuan UniversityChengdu610065China College of Hydraulic and Hydroelectric Engineering Sichuan UniversityChengdu610065China Chengdu Planning Information Technic Center Chengdu610042China

With the continuous development of the oblique photography technique, it has been used more and more widely in the field of geological disasters. It can quickly obtain the three-dimensional(3D) real scene model of dangerous mountainous areas under the premise of ensuring the safety of personnel while restoring the real geographic information as much as possible. However, geological disaster areas are often accompanied by many adverse factors such as cliffs and dense vegetation. Based on this, the paper introduced the flight line design of oblique photogrammetry, analyzed the multi-platform data fusion processing, studied the multi-period data dynamic evaluation technology and proposed the application methods of data acquisition, early warning, disaster assessment and decision management suitable for geological disaster identification through the analysis of actual cases, which will help geologists to plan and control geological work more scientifically and rationally, improve work efficiency and reduce the potential personnel safety hazards in the process of geological survey, to offer technical support to the application of oblique photogrammetry in geological disaster identification and decision making and provide the scientific basis for personal and property safety protection and later-stage geological disaster management in disaster areas.

关键词： Oblique photography technique Three-dimensional models Geological hazards Data integration Disaster assessment Decision management

Recent advances in slippery liquid-infused surfaces with unique properties inspired by nature

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Bio-Design and Manufacturing 2021年第3期4卷 506-525页

作者： xi Zeng Zhiguang Guo Weimin liu MOE Key Laboratory of Green Preparation and Application for Functional Materials Hubei UniversityWuhan 430062China State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China

The slippery liquid-infused porous surface(s)(SLIPS)that imitates the Nepenthes pitcher plant has proven to be highly versatile and can be combined with various surface characteristics such as dynamic response,antifouling,selective adhesion,and optical/mechanical *** addition,the introduction of a lubricating fluid layer also gives it extremely low contact angle hysteresis and self-repairing properties,which further expands its application ***,SLIPS has been proven to be suitable for many frontier fields such as aerospace,communications,biomedicine,and microfluidic *** this review,we explain the theoretical background of SLIPS and the preparation methods currently available,including the choice of substrate materials and lubricants,and we discuss the design parameters of the liquid injection surface and how to deal with the consumption of lubricants in practical *** addition,the paper focuses on current and potential applications,such as preventing pathogen contamination of and blood adhesion of medical equipment,manipulation of tiny droplets,and directional transportation of ***,some weaknesses that appear when SLIPS is used in these applications are pointed out,which provides a new perspective for the development of SLIPS in the future.

关键词： SLIPS Lubricant-infused Slippery Repellent surface Preparation Application

Bioengineered miR-328-3p modulates GLUT1-mediated glucose uptake and metabolism to exert synergistic antiproliferative effects with chemotherapeutics

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Acta Pharmaceutica Sinica B 2020年第1期10卷 159-170页

作者： Wanrong Yi mei-Juan Tu Zhenzhen liu Chao Zhang Neelu Batra Ai-xi Yu Ai-Ming Yu Department of Orthopaedic Trauma and Microsurgery Zhongnan Hospital of Wuhan UniversityWuhan 430072China Department of Biochemistry&Molecular Medicine UC Davis School of MedicineSacramento 95817CAUSA

MicroRNAs(miRNAs or miRs)are small noncoding RNAs derived from genome to control target gene *** we have developed a novel platform permitting high-yield production of bioengineered miRNA agents(BERA).This study is to produce and utilize novel fully-humanized BERA/miR-3’28-3p molecule(hBERA/miR-3’28)to delineate the role of miR-328-3p in controlling nutrient uptake essential for cell *** first demonstrated successful high-level expression of hBERA/miR-328 in bacteria and purification to high degree of homogeneity(>98%).Biologic miR-328-3p prodrug was selectively processed to miR-328-3p to suppress the growth of highly-proliferative human osteosarcoma(OS)*** glucose transporter protein type 1,gene symbol solute carrier family 2 member 1(GUJTHSLC2A1),we identified and verified large neutral amino acid transporter 1,gene symbol solute carrier family 7 member 5(LPAT1/SLC7A5)as a direct target for miR-3’*** reduction of LAT1 protein levels by miR-3’28-3p did not alter homeostasis of amino acids within OS cells,suppression of GLUT1 led to a significantly lower glucose uptake and decline in intracellular levels of glucose and glycolytic metabolite ***,combination treatment with hBERA/miR-3’28 and cisplatin or doxorubicin exerted a strong synergism in the inhibition of OS cell *** findings support the utility of novel bioengineered RNA molecules and establish an important role of miR-328-3p in the control of nutrient transport and homeostasis behind cancer metabolism.

关键词： Bioengineered RNA MiR-328 LAT1 GLUT1 Chemosensitivity Cancer

In vitro biocompatibility evaluation of silk-fibroin/ polyurethane membrane with cultivation of HUVECs

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Frontiers of Materials Science 2014年第1期8卷 63-71页

作者： mei ZHOU Wei-Ci WANG Yong-Gui LIAO Wen-Qi liu Miao YU Chen-xi OUYANG Department of Vascular Surgery Union Hospital Tongji Medical College Huazhong University of Science and Technology Wuhan 430022 China

In order to investigate the in vitro biocompatibility of a novel polyurethane （PU） membrane modified by incorporation of superfine silk-fibroin powder （SFP）, which was prepared for small-diameter vascular grafts, with the cultivation of human umbilical vein endothelial cells （HUVECs）, PU and SFP were mixed with the ratios of 9：1, 7：3, 5：5, 3：7 （PU：SFP） to make four composite materials. Unmodified PU and polytetrafluoroethylene （PTFE） were added as control groups. CCK-8 assay was used to evaluate the cytotoxicity of these biomaterials. Data were processed using SPSS, and P〈 0.05 was considered to be statistically significant. Adherence and spreading of HUVECs on the surface of specimens was observed using direct contact cultivation. The toxicity ratings of the novel composites were grade 0-1, which is in the acceptable range. In all the experimental groups except control, SFP/PU with ratio of 1：9 had the least cytotoxicity property, and more content of SFP in the composite showed no improvement of the biocompatibility. HUVECs strongly attached to and grew on the surface of the biomaterials, and proliferated rapidly. The proliferation ability increased with increased proportion of SFP; however the cell quantity on the surface of the materials decreased when the proportion of SFP was equal to or larger than that of PU in the composite. It is concluded that this novel material has excellent cellular affinity with no cytotoxicity to HUVECs. Adding SFP gives PU better biocompatibility, while further research on optimum blend ratios is still needed.

关键词： polyurethane (PU) silk-fibroin (SF) small diameter vascular graft biocompatibility human umbilical vein endothelial cell (HUVEC)

Multi-objective optimization of equipment capacity and heating network design for a centralized solar district heating system

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Building Simulation 2023年第1期16卷 51-67页

作者： Yanfeng liu Ting Mu xi Luo School of Building Services Science and Engineering Xi'an University of Architecture and TechnologyXi'an 710055China State Key Laboratory of Green Building in Western China Xi'an 710055China

Northwest China has abundant solar energy resources and a large demand for winter *** solar energy for centralized heating is a clean and effective way to solve local heating *** present studies usually decoupled solar heating stations and the heating network in the optimization design of centralized solar heating systems,this study developed a joint multi-objective optimization model for the equipment capacity and the diameters of the heating network pipes of a centralized solar district heating system,using minimum total life cycle cost and CO_(2)emission of the system as the optimization *** typical cities in northwest China with different solar resource conditions(Lhasa,xining,and xi'an)were selected as cases for *** to the results,the solar heating system designed using the method proposed in this study presents lower economic cost and higher environmental protection in comparison to separately optimizing the design of the solar heating station and the heating ***,the solar fraction of the optimal systems are 90%,70%,and 31%for Lhasa,xining,and xi'an,and the minimum water supply temperatures are 55℃,50℃,and 65℃for an optimal economy and 55℃,45℃,and 45℃for optimal environmental protection,*** was also established that the solar collector price has a greater impact on the equipment capacity of the solar heating station than the gas boiler price.

关键词： solar energy solar energy system district heating optimization design genetic algorithm

Effects of fluid recirculation on mass transfer from the arterial surface to flowing blood

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Acta Mechanica Sinica 2012年第3期28卷 904-910页

作者： Zhi-Guo Zhang xi-Wen Zhang Ying-xi liu Department of Engineering Mechanics Faculty of Vehicle Engineering and MechanicsState Key Laboratory of Structural Analysisfor Industrial EquipmentDalian University of Technology116024 DalianChina School of Aerospace Tsinghua University100084 BeijingChina

The effect of disturbed flow on the mass trans- fer from arterial surface to flowing blood was studied nu- merically, and the results were compared with that of our previous work. The arterial wall was assumed to be vis- coelastic and the blood was assumed to be incompressible and non-Newtonian fluid, which is more close to human arte- rial system. Numerical results indicated that the mass trans- fer from the arterial surface to flowing blood in regions of disturbed flow is positively related with the wall shear rates and it is significantly enhanced in regions of disturbed flow with a local minimum around the reattachment point which is higher than the average value of the downstream. There- fore, it may be implied that the accumulation of cholesterol or lipids within atheromatous plaques is not caused by the reduced efflux of cholesterol or lipids, but by the infiltration of the LDL （low-density lipoprotein） from the flowing blood to the arterial wall.

关键词： Disturbed flow Arterial wall Mass transfer Atherosclerosis Wall shear rates

Effects of the shape and size of rectangular inclusions on the fatigue cracking behavior of ultra-high strength steels

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International Journal of Minerals,Metallurgy and Materials 2013年第4期20卷 360-364页

作者： Yan-ping Zeng Hong-mei Fan xi-shan xie School of Materials Science and Engineering University of Science and Technology Beijing

The fatigue cracking behavior of ultra-high strength steels containing rectangular inclusions of small sizes were investigated based on in situ observations by scanning electron microscopy （SEM）. The size and shape of rectangular inclusions affect markedly the initiation site and propagation path of a fatigue crack. Especially, the initiation site of a fatigue crack depends strongly on the angle between the long-axis of a rectangle inclusion and the loading direction, and the length/width ratio of this rectangle inclusion because the residual stress distribution fields vary with these conditions. The results coincide very well with those of finite element analysis.

关键词： high strength steel inclusions fatigue of materials crack initiation crack propagation

Astrophysical constraints on the proton-to-electron mass ratio with FAST

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Research in Astronomy and Astrophysics 2019年第2期19卷 15-24页

作者： xi Chen Simon P.Ellingsen Ying mei Center for Astrophysics Guangzhou University Shanghai Astronomical Observatory Chinese Academy of Sciences School of Physical Sciences University of Tasmania

That the laws of physics are the same at all times and places throughout the Universe is one of the basic assumptions of physics. Astronomical observations provide the only means to test this basic assumption on cosmological time and distance scales. The possibility of variations in the dimensionless physical constant μ-the proton-to-electron mass ratio, can be tested by comparing astronomical measurements of the rest frequency of certain spectral lines at radio wavelengths with laboratory determinations. Different types of molecular transitions have different dependencies on μ and so observations of two or more spectral lines towards the same astronomical source can be used to test whether there is any evidence for either temporal or spatial changes in the physical fundamental constants. μ will change if the relative strength of the strong nuclear force compared to the electromagnetic force varies. Theoretical studies have shown that the rotational transitions of some molecules which have transitions in the frequency range that will be covered by FAST(e.g., CH_3 OH, OH and CH) are sensitive to changes in μ. A number of studies looking for possible variations in μ have been undertaken with existing telescopes, however, the greater sensitivity of FAST means it will open new opportunities to significantly improve upon measurements made to *** this paper, we discuss which molecular transitions and sources(both in the Galaxy and external galaxies)are likely targets for providing improved constraints on μ with FAST.

关键词： ISM:molecules radio lines:ISM techniques:radial velocities elementary particles

μ-Synthesis control with reference model for aeropropulsion system test facility under dynamic coupling and uncertainty

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Chinese Journal of Aeronautics 2023年第10期36卷 246-261页

作者： Jiashuai liu xi WANG xi liu meiyin ZHU xitong PEI Song ZHANG Zhihong DAN School of Energy and Power Engineering Beihang UniversityBeijing 100191China Zhongfa Aviation Institute Beihang UniversityHangzhou 311115China Research Institute of Aero-Engine Beihang UniversityBeijing 100191China Science and Technology on Altitude Simulation Laboratory AECC(Aero Engine Corporation of China)Sichuan Gas Turbine EstablishmentMianyang 621703China

Due to the dynamic coupling and multi-source uncertainties,it is difficult to accurately control the pressure and temperature of the Aeropropulsion System Test Facility(ASTF)in the presence of rapid command and large *** paper presents the design ofμ-synthesis control to solve the *** incorporating the pressure ratio into the linear equation of the control valve,the modeling error of ASTF in the low frequency range is effectively ***,an uncertain model is established by considering various factors,including parameter variations,modeling error in the low frequency range,unmodeled dynamics,and changes in the working *** address the dynamic coupling,a diagonal reference model with desired performance is incorporated intoμ-***,all weighting functions are designed according to the performance ***,theμ-controller is obtained by using the standardμ-synthesis *** results indicate that theμ-controller decouples the pressure and temperature dynamics of *** with the multivariable PI controller,integral-μcontroller,and double integral-μcontroller,the proposedμ-controller can achieve higher transient accuracy and better disturbance ***,the robustness of theμ-controller is demonstrated by Monte Carlo simulations.

关键词： Aeropropulsion System Test Facility(ASTF) Decoupling Robustness μ-Synthesis Uncertainty