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Numerical study of compression corner flowfield using gao-yong turbulence model

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航空动力学报 2012年第1期27卷 124-128页

作者： gao Ge ZHANG Chang-xian YAN Wen-hui WANG yong National Key Laboratory of Science and Technology on Aero-Engine Aero-thermodynamics School of Jet PropulsionBeijing University of Aeronautics and AstronauticsBeijing 100091China Chinese Aeronautical Establishment Beijing 100012China

A numerical simulation of shock wave turbulent boundary layer interaction induced by a 24° compression corner based on gao-yong compressible turbulence model was presented.The convection terms and the diffusion terms were calculated using the second-order AUSM(advection upstream splitting method) scheme and the second-order central difference scheme,respectively.The Runge-Kutta time marching method was employed to solve the governing equations for steady state solutions.Significant flow separation-region which indicates highly non-isotropic turbulence structure has been found in the present work due to intensity interaction under the 24° compression corner.Comparisons between the calculated results and experimental data have been carried out,including surface pressure distribution,boundary-layer static pressure profiles and mean velocity profiles.The numerical results agree well with the experimental values,which indicate gao-yong compressible turbulence model is suitable for the prediction of shock wave turbulent boundary layer interaction in two-dimensional compression corner flows.

关键词： shock wave turbulent boundary layer interaction gao-yong compressible turbulence model compression corner flow

TDOA estimation of dual-satellites interference localization based on blind separation

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Journal of Systems Engineering and Electronics 2019年第4期30卷 696-702页

作者： SU Ting GAO Yong College of Electronics and Information Engineering Sichuan University

The time difference of arrival(TDOA)estimation plays a crucial role in the accurate localization of the satellite interference source.In the dual-satellites interference source localization system,the target signal from the adjacent satellite is likely to be interfered by the normal communication signal with the same frequency.Therefore,the signal to noise ratio(SNR)of the target signal would become too low,and the TDOA estimation through cross-correlation processing would be unreliable or even unattainable.This paper proposes a technique based on blind separation to solve the co-channel interference problem,where separation of the mixed signal can be carried out by the particle filter(PF)algorithm.The experimental results show that the proposed method could achieve more accurate TDOA estimation.The measured data obtained by using the software radio platform at 915 MHz and 2 GHz respectively verify the effectiveness of the proposed method.

关键词： time difference of arrival(TDOA) co-channel interference blind separation particle filter(PF)

Astrocytes in Chronic Pain:Cellular and Molecular Mechanisms

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Neuroscience Bulletin 2023年第3期39卷 425-439页

作者： Huan-Jun Lu yong-Jing gao Institute of Pain Medicine and Special Environmental Medicine Co-innovation Center of NeuroregenerationNantong UniversityNantong 226019China

Chronic pain is challenging to treat due to the limited therapeutic options and adverse side-effects of therapies.Astrocytes are the most abundant glial cells in the central nervous system and play important roles in different pathological conditions,including chronic pain.Astrocytes regulate nociceptive synaptic transmission and network function via neuron–glia and glia–glia interactions to exaggerate pain signals under chronic pain conditions.It is also becoming clear that astrocytes play active roles in brain regions important for the emotional and memory-related aspects of chronic pain.Therefore,this review presents our current understanding of the roles of astrocytes in chronic pain,how they regulate nociceptive responses,and their cellular and molecular mechanisms of action.

关键词： Astrocyte Microglia Neuron-glia interaction Spinal cord Chronic pain

Soft Tissue Deformation Modeling in the Procedure of Needle Insertion:A Kriging‑Based Method

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Chinese Journal of Mechanical Engineering 2022年第3期35卷 187-199页

作者： yong Lei Murong Li Dedong gao State Key Laboratory of Fluid Power and Mechatronic Systems Zhejiang UniversityHangzhou 310027China School of Mechanical Engineering Qinghai UniversityXining 810016China

The simulation and planning system(SPS)requires accurate and real-time feedback regarding the deformation of soft tissues during the needle insertion procedure.Traditional mechanical-based models such as the finite element method(FEM)are widely used to compute the deformations of soft tissue.However,it is difficult for the FEM or other methods to find a balance between an acceptable image fidelity and real-time deformation feedback due to their complex material properties,geometries and interaction mechanisms.In this paper,a Kriging-based method is applied to model the soft tissue deformation to strike a balance between the accuracy and efficiency of deformation feedback.Four combinations of regression and correlation functions are compared regarding their ability to predict the maximum deformations of ten characteristic markers at a fixed insertion depth.The results suggest that a first order regression function with Gaussian correlation functions can best fit the results of the ground truth.The functional response of the Kriging-based method is utilized to model the dynamic deformations of markers at a series of needle insertion depths.The feasibility of the method is verified by investigating the adaptation to step variations.Compared with the ground truth of the finite element(FE)results,the maximum residual is less than 0.92 mm in the Y direction and 0.31 mm in the X direction.The results suggest that the Kriging metamodel provides real-time deformation feedback for a target and an obstacle to a SPS.

关键词： Kriging metamodel Needle insertion Real-time simulator Soft tissue deformation

Flexibility Improvement of CHP Unit for Wind Power Accommodation

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Journal of Modern Power Systems and Clean Energy 2022年第3期10卷 731-742页

作者： Dongming Zhang yong Hu Yaokui gao School of Control and Computer Engineering North China Electric Power UniversityBeijingChina

Improving the flexibility of combined heat and power(CHP)units is an important way to solve the problem of wind power accommodation in northern China.Firstly,this paper analyzes the principle of an extraction-type CHP unit,calculates its safe operation range,and analyzes its contradiction between heating and peaking.Secondly,the safe operation ranges of the CHP unit with several flexibility modifications are further calculated,which involve two-stage bypass,low-pressure cylinder(LPC)removal,heat storage tank,and electric boiler.Finally,based on the safe operation ranges,their effects on improving the capabilities of deep peak shaving and wind power accommodation are compared,and their adaptabilities to different wind scenarios are analyzed.The results show that:①all flexibility modifications can improve the deep peak shaving capability of the CHP unit,especially for the two-stage bypass and the electric boiler;②LPC removal modification can accommodate wind power to some extent,but most of wind power is still abandoned;③heat storage tank modification is unstable in different wind scenarios,which is determined by the surplus heating capability during the daytime.

关键词： Combined heat and power(CHP) flexibility bypass low-pressure cylinder(LPC)removal heat storage tank electric boiler

Improved uranium leaching efficiency from low-permeability sandstone using low-frequency vibration in the CO_(2)+O_(2) leaching process

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Journal of Rock Mechanics and Geotechnical Engineering 2022年第3期14卷 770-780页

作者： yong Zhao yong gao Caiwu Luo Jun Liu School of Resource Environment and Safety Engineering University of South ChinaHengyang421001China Department of Nuclear Safety China Institute of Atomic EnergyBeijing100000China College of Humanities and Foreign Languages Xi’an University of Science and TechnologyXi’an710054China China Coal Technology Engineering Group Chongqing Research Institute Chongqing 400039China

Extraction of uranium from low-permeability sandstone is a long-standing challenge in mining.The improvement of sandstone permeability has therefore become a key research focus to improve the uranium leaching effect.To address the low-permeability problem and corresponding leaching limits,leaching experiments are performed using newly developed equipment that could apply low-frequency vibration to the sandstone samples.The test results indicate that low-frequency vibration significantly improves the uranium leaching performance and permeability of the sandstone samples.The leaching effect of low-frequency vibration treatment is approximately nine times more effective than ultrasonic vibration treatment,whereas the concentration of uranium ions generated without vibration treatment is not detectable.Mathematical model that considers the combined action of physico-mechanical vibration and chemical erosion is established to describe the effect of low-frequency vibration on the permeability.The calculated results are in good agreement with the tested permeability values.This study thus offers a new method to effectively leach more uranium from low-permeability sandstone using CO_(2)+O_(2)and provides an insight into the impact of low-frequency vibration on the uranium leaching process.

关键词： Uranium leaching Low-frequency vibration Chemical erosion Low permeability Permeability model

Microbiome research outlook:past,present,and future

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Protein & Cell 2023年第10期14卷 709-712页

作者： Yunyun gao Danyi Li yong-Xin Liu Shenzhen Branch Guangdong Laboratory of Lingnan Modern AgricultureGenome Analysis Laboratory of the Ministry of Agriculture and Rural AffairsAgricultural Genomics Institute at ShenzhenChinese Academy of Agricultural SciencesShenzhen 518120China R-Institute Co.Ltd. Beijing 100011China

With its critical role in human health and disease,the microbiome has transformed modern biology.Over the past few years,microbiome research has evolved rapidly,with microbiologists gradually shifting their focus from cataloging microorganisms in the human microbiome to understanding their functional roles and how they interact with the host.Here,we present the global trends in microbiome research and summarize the past and current work on microbiome published in Protein&Cell.

关键词： shifting transformed outlook

Clinical effect of acupuncture along fascia,meridians,and nerves combined with ultrasound-guided paravertebral nerve block in the treatment of postherpetic neuralgia:a randomized parallel-controlled study

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Journal of Traditional Chinese Medicine 2023年第2期43卷 359-364页

作者： gao Xiumei WANG Chenyan NI yong ZHANG Huiling Department of Anesthesiology Xiyuan Hospital China Academy of Chinese Medical ScienceBeijing 100091China Pain Department the Second Affiliated Hospital of Soochow UniversitySuzhou 215123China Department of Pharmacology and Laboratory of Cerebrovascular Pharmacology College of Pharmaceutical ScienceSoochow UniversitySuzhou 215123China

OBJECTIVE:To observe the clinical efficacy of acupuncture along fascia,meridians,and nerves combined with ultrasound-guided nerve blockage in the treatment of postherpetic neuralgia.METHODS:A total of 61 outpatients with post-chest and back herpes zoster neuralgia were recruited in the Department of Pain at the Xiyuan Hospital,China Academy of Chinese Medical Sciences from May 2019 to June 2021.They were randomly divided into two groups.Thirty-one patients in the control group were treated with ultrasound-guided thoracic paravertebral nerve block(PVB)alone,one patient declined to continue during treatment(n=30),and thirty patients in the observation group received the acupuncture along the fascia,meridians,and nerves combined with ultrasound-guided PVB treatment(n=30).Both control and observation group received treatment weekly for 4 weeks.The medical history data such as age,sex,presence or absence of comorbidities and disease course were analyzed.The visual analog scale(VAS)score was used to assess the pain degree of two groups at T0(before treatment),T1(1-time treatment ended),T2(2 times treatment ended),T3(3 times treatment ended),and T4(4 times treatment ended).The sleep state was examined by Pittsburgh Sleep Quality Index(PSQI)before and after the study.RESULTS:There was no significant difference in general conditions between the control group and the observation group(P>0.05).The VAS score in both control and observation group was decreased in a time-dependent manner after 1-4 weeks of treatment.There were no significant differences in VAS scores between the two groups after 1 or 2 weeks of treatment(P>0.05).After 3 and 4 weeks of treatment,the VAS score was significantly decreased in the observation group compared with that in the control group(P<0.001).In addition,the reduction in VAS score(after treatment-before treatment)between the two groups was statistically significant[D value:-1.53,95%CI(-2.32,0.74),P<0.001].Furthermore,the sleep state of patients in both groups markedly improved and much obvious

关键词： neuralgia postherpetic visual analog scale acupuncture along fascia meridians and nerves ultrasound-guided paravertebral nerve block

Impact of utility-scale solar photovoltaic array on the aeolian sediment transport in Hobq Desert, China

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Journal of Arid Land 2021年第3期13卷 274-289页

作者： TANG Guodong MENG Zhongju GAO Yong DANG Xiaohong College of Desert Control Science and Engineering Inner Mongolia Agricultural UniversityHohhot 010018China

Deserts are ideal places to develop ground-mounted large-scale solar photovoltaic (PV) powerstation. Unfortunately, solar energy production, operation, and maintenance are affected bygeomorphological changes caused by surface erosion that may occur after the construction of the solar PVpower station. In order to avoid damage to a solar PV power station in sandy areas, it is necessary toinvestigate the characteristics of wind-sand movement under the interference of solar PV array. The studywas undertaken by measuring sediment transport of different wind directions above shifting dunes andthree observation sites around the PV panels in the Hobq Desert, China. The results showed that the twoparameterexponential function provides better fit for the measured flux density profiles to the near-surfaceof solar PV array. However, the saltation height of sand particles changes with the intersection anglebetween the solar PV array and wind direction exceed 45°. The sediment transport rate above shifting duneswas always the greatest, while that around the test PV panels varied accordingly to the wind direction.Moreover, the aeolian sediment transport on the solar PV array was significantly affected by wind direction.The value of sand inhibition rate ranged from 35.46% to 88.51% at different wind directions. When theintersection angle exceeds 45°, the mean value of sediment transport rate above the solar PV array reducesto 82.58% compared with the shifting dunes. The results of our study expand our understanding of theformation and evolution of aeolian geomorphology at the solar PV footprint. This will facilitate the designand control engineering plans for solar PV array in sandy areas that operate according to the wind regime.

关键词： aeolian sediment transport mass flux density profiles sand-fixation shelter efficacy solar photovoltaic array