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Science Bulletin 2017年第16期62卷 1109-1113页

作者： Yue-liang Wu International Centre for Theoretical Physics Asia-Pacific(ICTP-AP).Beijing 100190 China Institute of Theoretical Physics Chinese Academy of SciencesBeijing 100190.China University of Chinese Academy of Sciences(UCAS) Beijing 100049China

The theory of general relativity(GR)[1,2]has successfully built a relation between the geometry of spacetime and the energymomentum tensor of *** has extensively quested for potential unified models of electromagnetis... 详细信息

关键词：统一场论引力源对称性时空基本粒子中尺度能量-动量张量广义相对论

Repurposing an old anti-fungal drug as a Hedgehog inhibitor

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Protein & Cell 2010年第5期1卷 417-418页

作者： Camilla Giambelli Dennis liang Fei Huaizhi Wang David j.Robbins Molecular Oncology Program DeWitt Daughtry Family Department of SurgeryUniversity of MiamiMiamiFL 33136USA Department of Pharmacology and Toxicology Dartmouth Medical SchoolHanoverNH 03755USA Institute of Hepatopancreatobiliary Surgery of PLA Southwest HospitalThird Military Medical UniversityChongqing 400038China

It requires approximately 800 million dollars(US)and 10 years to successfully bring a drug from the laboratory bench into the clinic(DiMasi et al.,2003).Thus,the breakthrough discovery of today will not be available in the clinic for many years,and many dollars,after this initial *** potential way to speed up this drug developmental cycle is by repurposing drugs that have been previously approved for an alternate clinical *** this goal in mind,Beachy and colleagues set out to identify a drug with efficacy against tumors that were dependant on the Hedgehog(HH)signaling *** reported in the April issue of a leading cancer research journal that Itraconazole,a commonly used antifungal drug,can be turned against HH’s signaling function(Kim et al.,2010).It has been estimated that 25%of all human tumors may be HH dependent(Teglund et al,2010).

关键词： al. drugs dollar

Late Paleozoic–Mesozoic subduction and accretion of the Paleo-Pacific Plate: Insights from ophiolitic rocks in the Wandashan accretionary complex, NE China

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Geoscience Frontiers 2021年第6期12卷 171-191页

作者： Yong liang Han zheng Huan Li Thomas j.Algeo Xiao-Meng Sun School of Geosciences and Info-Physics Central South UniversityChangsha 410083China State Key Laboratory of Biogeology and Environment Geology School of Earth SciencesChina University of GeosciencesWuhan 430074China State Key Laboratory of Geological Processes and Mineral Resources School of Earth SciencesChina University of GeosciencesWuhan 430074China Department of Geology University of CincinnatiCincinnatiOH 42221-0013USA College of Earth Sciences Jilin UniversityChangchun 130061China

The Wandashan accretionary complex(AC),consisting of the Raohe and Yuejinshan complexes,is located on the continental margin of Northeast Asia and represents an excellent source of information about Paleo-Pacific subduction and ***,the protolith nature and tectonic evolution of the Wandashan AC are under *** contribution reports new geochronological,geochemical,and Sr-Nd-Pb-Hf isotopic data for ophiolitic rocks from the Wandashan *** 169–166 Ma plagioclasites and homogeneous gabbros from the Raohe complex are OIBs while 228–214 Ma homogeneous gabbros are continental *** gabbros from the Yuejinshan complex formed at 280–278 Ma and~220 Ma and have similar characteristics with E-MORB and N-MORB,*** are BABBs and their primary magma was derived from a source region between EMI and EMII that was affected by continental crustal contamination as well as subduction-zone *** with previous studies,we suggest that the onset of subduction of the Paleo-Pacific Plate was in the Early ***,a back-arc basin,whose present suture is on the eastern margin of the jiamusi Massif,formed and widened during 280–232 Ma,after which the basin closed and BABBs were emplaced to form the Yuejinshan complex during 210–180 *** formation of VABs of the Raohe complex is coincident with the closure of the back-arc basin,and together with the 169–166 Ma OIBs,they constitute a major part of the Raohe *** accretionary process was completed during 133–131 *** together,the ophiolitic rocks indicating multistage magmatism in the Paleo-Wandashan region recorded the formation-closure process of back-arc basin and the accretionary process of the Wandashan AC,during the westward subduction of the Paleo-Pacific *** back-arc basin identified in our study sheds new lights on geodynamic evolution model of subduction and accretion of the Paleo-Pacific Plate on the continental margin of NE Asia.

关键词： Ophiolite Magma chemistry Tectonic evolution Back-arc basin Raohe complex Yuejinshan complex

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深度学习在心力衰竭检测中的应用综述

计算机科学与探索 2025年第1期19卷 65-78页

作者：王永威魏德健曹慧姜良山东中医药大学智能与信息工程学院济南250355

随着生物医学技术的发展,利用生物信号进行心力衰竭的早期诊断已成为提高患者生存率和降低治疗成本的关键策略。在此背景下,深度学习技术的迅猛发展为心力衰竭检测开辟了新路径。系统地综述了深度学习在心力衰竭检测中的最新进展和应用... 详细信息

随着生物医学技术的发展,利用生物信号进行心力衰竭的早期诊断已成为提高患者生存率和降低治疗成本的关键策略。在此背景下,深度学习技术的迅猛发展为心力衰竭检测开辟了新路径。系统地综述了深度学习在心力衰竭检测中的最新进展和应用。概述了心力衰竭检测涉及的主要生物医学信号和公开数据集。详细分析了深度学习在心力衰竭诊断领域的应用及其发展,特别是对卷积神经网络和长短期记忆网络处理心电图、心率变异性、心音等关键生物医学信号的能力进行了深入分析,总结了这些技术的优势、局限性,并对各类模型性能进行了比较。探讨了通过融合多种人工智能技术所构建的混合模型在提升检测精度和模型泛化能力方面的潜力,以及如何利用模型的可解释性来增加检测过程的透明度,提升医生的信任度。最后总结了当前研究存在的不足,并对未来研究方向提出展望,强调了跨学科合作在推动心力衰竭检测技术进步中的重要性。

关键词：心力衰竭生物医学信号深度学习卷积神经网络循环神经网络混合模型

Review and comparison of methods and benchmarks for automatic modal identification based on stabilization diagram

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journal of Traffic and Transportation Engineering(English Edition) 2024年第2期11卷 209-224页

作者： Min He Peng liang jiuxian Liu zhiqiang liang School of Architecture and Civil Engineering Xi'an University of Science and TechnologyXi'an 710064China School of Highway Chang'an UniversityXi'an 710064China

Automatic modal identification via automatically interpreting the stabilization diagram provides key technique in bridge structural health *** paper reviews the progress in the area of automatic modal identification based on interpreting the stabilization *** whole identification process is divided into four steps from establishing the stabilization diagram to removing the outliers in the identification *** criteria and algorithms used in each step in the existing studies are carefully summarized and *** between typical methods in cleaning and interpreting the stabilization diagram are also *** structure benchmarks used in the existing studies to validate the proposed automatic modal identification methods are also *** on the review and comparison,the specific ratio method for cleaning the stabilization diagram,the hierarchical clustering method for interpreting the stabilization diagram and the adjusted boxplot for removing the outliers in the identification results are the most suitable methods for each *** key point of automatic modal identification based on interpreting the stabilization diagram has also discussed,and it is recommended to pay more attention to cleaning the stabilization *** study about automatic modal identification under situation with very few sensors deployed should be more *** review aims to help researchers and practitioners in implementing existing automatic modal identification algorithms effectively and developing more suitable and practical methods for civil engineering structures in the future.

关键词： Bridge structural health monitoring Automatic modal identification Stabilization diagram Eriteria and methods Real structure benchmarks

Evaluation of CMIP6 HighResMIP models in simulating precipitation over Central Asia

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Advances in Climate Change Research 2022年第1期13卷 1-13页

作者： liang-liang LI jian LI Ru-Cong YU College of Atmospheric Sciences Lanzhou UniversityLcmzhou 730000China State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesBeijing 100081China Research Center for Disastrous Weather Over Hengduan Mountains&Low-Latitude Plateau China Meteorological AdministrationKunming 650034China

The High Resolutio n Model Intercomparison Project(HighResMIP)experiment within the Coupled Model In tercomparison Project Phase 6(CMIP6),for the first time,has provided an opportunity to evaluate the performance of climate models over complex *** on the HighResMIP's historical simulations of atmospheric general circulation models,the performances of global high-resolution models,with a horizontal resolution finer than 50 km,in representing precipitation over Central Asia were evaluated using rain gauge observation *** the models successfully reproduce the large precipitation regions that are located over the mountainous areas and Northern Central ***,nearly all the models overestimate precipitation frequency over Central Asia and large overestimations of precipitation amount and frequency are located over the mountainous *** the HighResMIP multi-model ensemble mean performs better than all individual models at simulating the spatial pattern of precipitation frequency,it is inferior to HadGEM3-GC31-HM and ECMWF-IFS-HR at simulating that of precipitation *** simulation performance exhibits remarkable regional *** the Qilian Mountains,the relationship between precipitation and elevation is totally captured by climate *** contrast,over the Tianshan Mountains,the models fail to simulate the decrease in precipitation frequency after elevation higher than the maximum precipitation *** models successfully reproduce the annual cycle shape of precipitation amount over the Southern Central Asia,Qilian Mountains and Tianshan Mountains,but fail to reproduce it over the Northern Central *** than half of the high-resolution GCMs have a reduced bias relative to the corresponding low-resolution *** performances of most high-resolution GCMs in simulating precipitation pattern are well over the Tianshan Mountains.

关键词： CMIP6 HighResMIP Model evaluation Precipitation Elevation Central Asia

Coupled Lagrangian impingement spray model for doublet impinging injectors under liquid rocket engine operating conditions

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Chinese journal of Aeronautics 2017年第4期30卷 1391-1406页

作者： Qiang WEI Guozhu liang School of Astronautics Beihang University Beoing 100083 China

To predict the effect of the liquid rocket engine combustion chamber conditions on the impingement spray, the conventional uncoupled spray model for impinging injectors is extended by considering the coupling of the jet impingement process and the ambient gas field. The new coupled model consists of the plain-orifice sub-model, the jet-jet impingement sub-model and the droplet collision sub-model. The parameters of the child droplet are determined with the jet-jet impingement sub-model using correlations about the liquid jet parameters and the chamber *** overall model is benchmarked under various impingement angles, jet momentum and offcenter ratios. Agreement with the published experimental data validates the ability of the model to predict the key spray characteristics, such as the mass flux and mixture ratio distributions in quiescent air. Besides, impinging sprays under changing ambient pressure and non-uniform gas flow are investigated to explore the effect of liquid rocket engine chamber conditions. First, a transient impingement spray during engine start-up phase is simulated with prescribed pressure profile. The minimum average droplet diameter is achieved when the orifices work in cavitation state, and is about 30% smaller than the steady single phase state. Second, the effect of non-uniform gas flow produces off-center impingement and the rotated spray fan by 38°. The proposed model suggests more reasonable impingement spray characteristics than the uncoupled one and can be used as the first step in the complex simulation of coupling impingement spray and combustion in liquid rocket engines.

关键词： Combustion chamber Doublet impinging injector Impingement spray model Lagrangian method Liquid rocket engine

Transient simulation of a differential piston warm gas self-pressurization system for liquid attitude and divert propulsion system

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Chinese journal of Aeronautics 2018年第4期31卷 698-709页

作者： zhongjian FANG Guozhu liang School of Astronautics Beihang University

In order to obtain the dynamic characteristics of a differential piston warm gas selfpressurization system for liquid attitude and divert propulsion system, a transient model is developed using the modular modeling method. The system includes the solid start cartridge,pressure-amplified tank with liquid monopropellant, liquid regulator, gas generator, and *** one-dimensional finite-element state-variable model is applied to the pipes and the lumped parameter method is adopted for the other modules. The variations of the system operation parameters over time during the startup, steady-state, and pulsing operational processes are obtained from the transient model, and the characteristics of starting time changing with different system parameters are also analyzed. It is shown that the system startup process can be divided into three distinct processes. The starting time monotonically changes with variations of the liquid regulator parameters, first decreasing and then increasing with the mass change of the solid propellant charge of the start cartridge, initial gas cavity volume of the pressure amplified tank and initial gas cushion of the propellant tank. The starting time can be reduced to less than 1.0 s（0.68–0.75 s for the current system）. For meeting the deviation requirements of ±10% of the steady-state propellant tank pressure, the positive deviation requirement is assured by the self-locking pressure and the negative deviation can be assured within an allowable maximum propellant tank volume flowrate（1.6 times the design value for the proposed system） for downstream thrusters for a designed system. The results from the simulation are useful as a guide for further system design and testing.

关键词： Differential piston Dynamic characteristics Dynamic models Liquid attitude and divert propulsion system Startup process Warm gas self-pressurization system

Feature selection for chemical process fault diagnosis by artificial immune systems

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Chinese journal of Chemical Engineering 2018年第8期26卷 1599-1604页

作者： liang Ming jinsong zhao Department of Chemical Engineering Tsinghua University Beijing Key Laboratory of Industrial Big Data System and Application Tsinghua University

With the Industry 4.0 era coming, modern chemical plants will be gradually transformed into smart factories, which sets higher requirements for fault detection and diagnosis(FDD) to enhance operation safety intelligence. In a typical chemical process, there are hundreds of process variables. Feature selection is a key to the efficiency and effectiveness of FDD. Even though artificial immune system has advantages in adaptation and independency on a large number of fault samples, antibody library construction used to be based on experience. It is not only time consuming, but also lack of scientific foundation in fault feature selection, which may deteriorate the FDD performance of the AIS. In this paper, a fault antibody feature selection optimization(FAFSO) algorithm is proposed based on genetic algorithm to optimize the fault antibody features and the antibody libraries' thresholds simultaneously. The performance of the proposed FAFSO algorithms is illustrated through the Tennessee Eastman benchmark problem.

关键词： Artificial immune system Genetic algorithm Feature selection

Low-Temperature and Surfactant-Free Synthesis of Mesoporous TiO_2 Sub-Micron Spheres for Efficient Dye-Sensitized Solar Cells

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journal of Materials Science & Technology 2016年第1期32卷 17-23页

作者： Kaimo Deng liang Li College of Physics Optoelectronics and Energy & Collaborative Innovation Center of Suzhou Nano Science and TechnologySoochow University

Dye-sensitized solar cells （DSSCs） are one of the most promising next-generation solar cells due to their advantages over other counterparts. The photoanode of DSSCs has a great effect on the photovoltaic per- formance. Traditional photoanode includes a bottom nanoparticle layer and an upper scattering layer for better light capture in longer wavelength. Mesoporous nanostructures with size comparable to the wavelength of visible light are considered to be excellent light scattering centers by providing extra places for dye loading. Developing a green synthetic method is of great importance. Herein we report a facile and surfactant-free synthesis of mesoporous futile TiO2 submicrometer-sized spheres at temperature as low as 70 ℃. DSSCs based on photoanodes with an upper scattering layer composed of as-obtained mesoporous spheres on nanoparticle dense layer demonstrate an 18.0% improvement of power conver- sion efficiency. This simple approach may offer an energy-efficient and environmentally friendly alternative for DSSCs fabrication.

关键词： Titanium dioxide Mesoporous Sub-micron Light scattering Dye-sensitized solar cells Energy harvesting