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The Pathway of China’s Integrated Delivery System:Based on the Analysis of the Medical Consortium Policies

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Current Medical Science 2022年第6期42卷 1164-1171页

作者： Huan gao Xing-li DU Jia-zhi liAO li xiang School of Medicine and Health Management Huazhong University of Science and TechnologyWuhan430030China Tongji Hospital Tongji Medical CollegeHuazhong University of Science and TechnologyWuhan430030China

With the deepening of China’s health-care reform,an integrated delivery system has gradually emerged with the function of improving the efficiency of the health-care delivery system.For China’s integrated delivery system,a medical consortium plays an important role in integrating public hospitals and primary care facilities.The first medical consortium policy issued after the COVID-19 pandemic apparently placed hope on accelerating the implementation of a medical consortium and tiered health-care delivery system.This paper illustrates the possible future pathway of China’s medical consortium through retrospection of the 10-year process,changes of the series of policies,and characteristics of the policy issued in 2020.We considered that a fully integrated medical consortium would be a major phenomenon in China's medical industry,which would lead to the formation of a dualistic care pattern in China.

关键词： health-care reform integrated delivery system medical consortium tiered health-care delivery system health policy

Deep learning-based subseasonal to seasonal precipitation prediction in southwest China:Algorithm comparison and sensitivity to input features

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Earth and Planetary Physics 2023年第4期7卷 471-486页

作者： GuoLu gao Yang li XueYun Zhou XiaoMing xiang JiaQi li ShuCheng Yin Ya’an Meteorological Observatory Sichuan Meteorological BureauYa’an Sichuan 625000China Plateau and Basin Rainstorm Drought and Flood Key Laboratory of Sichuan ProvinceChengdu 610000China College of Atmospheric Science Chengdu University of Information TechnologyChengdu 610225China Meteorological Observation and Data Centre Sichuan Meteorological BureauChengdu 610072China Leshan Meteorological Observatory Sichuan Meteorological BureauLeshan Sichuan 614000China Quanzhou Meteorological Observatory Fujian Meteorological BureauQuanzhou Fujian 362000China

The prediction of precipitation at subseasonal to seasonal(S2S)timescales remains an enormous challenge because of the gap between weather and climate predictions.This study compares three deep learning algorithms,namely,the long short-term memory recurrent(LSTM),gated recurrent unit(GRU),and recurrent neural network(RNN),and selects the optimal algorithm to establish an S2S precipitation prediction model.The models were evaluated in four subregions of the Sichuan Province:the Plateau,Valley,eastern Basin,and western Basin.The results showed that the RNN model had better performance than the LSTM and GRU models.This could be because the RNN model had an advantage over the LSTM model in the transformation of climate indices with positive and negative variations.In the validation of test datasets,the RNN model successfully predicted the precipitation trend in most years during the wet season(May-October).The RNN model had a lower prediction bias(within±10%),higher sign accuracy of the precipitation trend(~88.95%),and greater accuracy of the maximum precipitation month(>0.85).For the prediction of different lead times,the RNN model was able to provide a stable trend prediction for summer precipitation,and the time correlation coefficient score was higher than that of the National Climate Center of China.Furthermore,this study proposed a method to measure the sensitivity of the RNN model to different input features,which may provide unprecedented insights into the nonlinear relationship and complicated feedback process among climate systems.The results of the sensitivity distribution are as follows.First,the Niño 4 and Niño 3.4 indices were equally important for the prediction of wet season precipitation.Second,the sensitivity of the snow cover on the Tibetan Plateau was higher than that in the Northern Hemisphere.Third,an opposite sensitivity appeared in two different patterns of the Indian Ocean and sea ice concentrations in the Arctic and the Barents Sea.

关键词： recurrent neural network long short-term memory recurrent sensitivity analysis artificial intelligence explainability complex terrain southwest China

Application of Nonlinear Lamb Wave Mixing Method for Residual Stress Measurement in Metal Plate

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Chinese Journal of Mechanical Engineering 2023年第1期36卷 211-223页

作者： Jingpin Jiao li li xiang gao Quan Cheng Cunfu He Bin Wu Faculty of Materials and Manufacturing Beijing University of TechnologyBeijing 100124China

Harmonic nonlinear ultrasound can offer high sensitivity for residual stress measurements;however,it cannot be used for local stress measurements at a point in space and exhibits nonlinear distortions in the experimental system.This paper presents a feasibility study on the measurement of residual stress in a metal plate using a nonlinear Lamb wave-mixing technique.The resonant conditions for two Lamb waves to generate a mixing frequency wave are obtained via theoretical analysis.Finite element simulations are performed to investigate the nonlinear interactions between the two Lamb waves.Results show that two incident A0 waves interact in regions of material nonlinearity and generate a rightward S0 wave at the sum frequency.Residual stress measurement experiments are conducted on steel plate specimens using the collinear Lamb wave-mixing technique.By setting different delays for two transmitters,the generated sum-frequency component at different spatial locations is measured.Experimental results show that the spatial distribution of the amplitude of the sum-frequency component agrees well with the spatial distribution of the residual stress measured using X-rays.The proposed collinear Lamb wave-mixing method is effective for measuring the distribution of residual stress in metal plates.

关键词： Residual stress Lamb wave Collinear wave mixing Nondestructive testing Resonant conditions

Prediction of undeformed chip thickness distribution and surface roughness in ultrasonic vibration grinding of inner hole of bearings

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2024年第4期25卷 311-323页

作者： Yanqin li Daohui xiang Guofu gao Feng JIAO Bo ZHAO School of Mechanical and Power Engineering Henan Polyechnic UniversiryJiaozuo 454000.China

Ultrasonic vibration grinding differs from traditional grinding in terms of its material removal mechanism.The randomness of grain-workpiece interaction in ultrasonic vibration grinding can produce variable chips and impact the surface roughness of workpiece.However,previous studies used iterative method to calculate the unformed chip thickness(UCT),which has low computational efficiency.In this study,a symbolic difference method is proposed to calculate the UCT.The UCT distributions are obtained to describe the stochastic interaction characteristics of ultrasonic grinding process.Meanwhile,the UCT distribution characteristics under different machining parameters are analyzed.Then,a surface roughness prediction model is established based on the UCT distribution.Finally,the correctness of the model is verified by experiments.This study provides a quick and accurate method for predicting surface roughness in longitudinal ultrasonic vibration grinding.

关键词： Ultrasonic vibration grinding Undeformed chip thickness(UCT) Distribution characteristics Surface roughness

Event-based sliding mode control under denial-of-service attacks

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Science China(Information Sciences) 2022年第6期65卷 125-141页

作者： Yingxin TIAN xiang li Bo DONG Yabin gao ligang WU Department of Control Science and Engineering Harbin Institute of Technology School of Software Harbin Institute of Technology

This paper deals with the problem of estimator-based sliding mode control against denial-of-service(DoS) attacks and discrete events via a time-delay approach. A networked system is considered an uncertain dynamical system with matched and mismatched perturbations and exogenous disturbance in the network environment. A network-resource-aware event-triggering mechanism is designed with aperiodically releasing system measurements. Furthermore, to describe the DoS attack duration and inter-event time, a time-delay modeling approach considers the DOS attack duration and inter-event time as a “time delay” of the measurements between the sensor and controller over the network is proposed. Consequently, an intervaltime-delay system with uncertainties is formulated. A state-observer-based sliding mode controller, by which the ideal sliding mode can be achieved, is proposed against the DoS attacks. The resulting sliding motion is proved to be robust and stable with an Lgain performance. Finally, the effectiveness and applicability of the present sliding mode control are validated in a simulated pendulum system.

关键词： sliding mode control time delay uncertain system state observer event trigger

Surface ligand engineering on the optical properties of atomically precise AuAg nanoclusters

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Chinese Journal of Structural Chemistry 2023年第9期42卷 1-5页

作者： xiang liu Yifei Zhang Zhiwen li gao li Farid Taherkhani Hunan Drug Inspection Center Hunan Institute for Drug ControlChangsha410013China State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian116023China Institute of Catalysis for Energy and Environment College of Chemistry and Chemical EngineeringShenyang Normal UniversityShenyang110034China University of Chinese Academy of Sciences Beijing100049China Departments of Production Engineering Universität Bremen Bibliothekstraße 128359Germany

1.Introduction In recent decade,atomically precise metal nanoclusters,comprised of metal kernel and surface protecting ligands,have appeared as a new and promising nanomaterial for abundant applications,such as nanocatalysis,sensor,photoluminescence,a few to name,which is attributed to their electron energy quantization arising from quantum size effect[1].And the very recent investigations showed that the configuration of metal kernel and the electronic properties of metal nanoclusters with the same metal core are largely affected by the surface protecting ligands[[2],[3]].For example,the surface ligands can significantly alter the catalytic performance of metal nanocluster catalysts(e.***.activity and selectivity)in a positive way.We have found that the Au_(25)(SR)_(18)nanocluster with the aromatic ligands can give higher conversions and a markedly increasing selectivity toward the desired product[4].

关键词： precise clusters selectivity

Prognostic role of C-reactive protein to albumin ratio in lung cancer:An updated systematic review and meta-analysis

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Chronic Diseases and Translational Medicine 2024年第1期10卷 31-39页

作者： Zhendong Lu Siyun Fu Wei li xiang gao Jinghui Wang Department of Medical Oncology Beijing Tuberculosis and Thoracic Tumor Research InstituteBeijing Chest HospitalCapital Medical UniversityBeijingChina Cancer Research Center Beijing Chest HospitalBeijing Tuberculosis and Thoracic Tumor Research InstituteCapital Medical UniversityBeijingChina

Background: C-reactive protein to albumin ratio(CRP/Alb ratio,CAR)has been suggested as a potential prognostic biomarker in lung cancer.This updated systematic review and meta-analysis aimed to assess the association between CAR and lung cancer prognosis in current literature.Methods: A systematic search of databases was conducted to identify relevant studies published up to April 2023.Pooled hazard ratios(HRs)and 95%confidence intervals(CIs)were calculated to assess the association between CAR and overall survival(OS)and progression-free survival(PFS)and recurrence-free survival(RF)in lung cancer patients.Results: This meta-analysis includes 16 studies with a total of 5337 patients,indicating a significant association between higher CAR and poorer OS,PFS,and RFS in lung cancer patients,with a pooled HR of 1.78(95%CI=1.60-1.99),1.57(95%CI=1.36-1.80),and 1.97(95%CI=1.40-2.77),respectively.Conclusions: This updated meta-analysis provides evidence for the potential prognostic role of CAR in lung cancer,suggesting its utility as an effective and noninvasive biomarker for identifying high-risk patients and informing treatment decisions in a cost-effective manner.However,further large-scale studies will be necessary to establish the optimal cut-off value for CAR in lung cancer and confirm the present findings.

关键词： C-reactive protein to albumin ratio inflammation:biomarker lung cancer prognosis

Survey on Multi-period Mean-Variance Portfolio Selection Model

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Journal of the Operations Research Society of China 2022年第3期10卷 599-622页

作者： xiang-Yu Cui Jian-Jun gao Xun li Yun Shi School of Statistics and Management Shanghai University of Finance and EconomicsShanghai200433China School of Information Management and Engineering Shanghai University of Finance and EconomicsShanghai200433China Department of Applied Mathematics The Hong Kong Polytechnic UniversityHong KongChina Academy of Statistics and Interdisciplinary Sciences Faculty of Economics and ManagementEast China Normal UniversityShanghai200062China

Due to the non-separability of the variance term,the dynamic mean-variance(MV)portfolio optimization problem is inherently difficult to solve by dynamic programming.li and Ng(Math Finance 10(3):387-406,2000)and Zhou and li(Appl Math Optim 42(1):19-33,2000)develop the pre-committed optimal policy for such a problem using the embedding method.Following this line of research,researchers have extensively studied the MV portfolio selection model through the inclusion of more practical investment constraints,realistic market assumptions and various financial applications.As the principle of optimality no longer holds,the pre-committed policy suffers from the time-inconsistent issue,i.e.,the optimal policy computed at the intermediate time t is not consistent with the optimal policy calculated at any time before time t.The time inconsistency of the dynamic MV model has become an important yet challenging research topic.This paper mainly focuses on the multi-period mean–variance(MMV)portfolio optimization problem,reviews the essential extensions and highlights the critical development of time-consistent policies.

关键词： Multi-period mean-variance Investment constraints Time inconsistency

Flowfield characteristics in sidewall compression inlets

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Acta Mechanica Sinica 2020年第3期36卷 678-685页

作者： gaoxiang xiang xiang gao Xuzhen Jie Xudong li Haoyang li Xiaopeng Chen School of Mechanics Civil Engineering and ArchitectureNorthwestern Polytechnical UniversityXi'an 710129China College of Geology and Environment Xi'an University of Science and TechnologyXi'an 710000China Beijing Institute of Aerospace Long March Vehicle Beijing 100076China

In this work,the flow fields in three-dimensional(3D)sidewall compression inlets are investigated theoretically and numerically.Combining spatial dimension reduction theory with the shock dynamics theory,a detailed analysis of the flowfield in the compression part of an inlet is proposed.Using this analytical approach,wave configurations are determined and flowfield parameters are solved;numerical simulations are conducted to validate these theoretical results.The effects of the attack angle and yaw angle on the pressure ratio,wave structures,and total pressure recovery performance are discussed in detail.Findings offer an effective way to study shock/shock interaction(SSI)in sidewall inlets,which is essential to the designing of such inlets.

关键词： Hypersonic flow Shock/shock interaction Flowfield characteristics