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Systematic review of risk factors for progressive ischemic stroke

Neural Regeneration Research 2011年第5期6卷 346-352页

作者： Weimin Yang Fanyi Kong ming liu Zilong hao Department of Neurology West China Hospital of Sichuan University Chengdu 610041 Sichuan Province China

OBJECTIVE： To determine the risk factors for progressive ischemic stroke, and to prevent onset and make a prognosis of disease, the present study systemically evaluated 19 cohort studies and 10 case-controlled studies of progressive ischemic stroke. SEARCH STRATEGY： A computer-based, online, literature search of PubMed （1966/2007）, China Biological Medicine Database （CBM-disc, 1979/2007） and CNKI （***, 1979/2007） was performed to screen for related studies. DATA SELECTION： Cohort or case-controlled studies that focused on risk factors of progressive ischemic stroke were selected for review. Two reviewers independently extracted data and assessed study quality according to Cochrane Collaboration guidelines. Statistical analysis was performed using RevMan software. MAIN OUTCOME MEASUREMENT： Risk factors for progressive ischemic stroke. RESULTS： Using the inclusion criteria, 29/781 studies published in English and Chinese were initially reviewed, including 19 cohort studies and 10 case-control studies. Despite variations in determination of progressive ischemic stroke and the intervals between 2 evaluations, all studies described the diagnostic criteria for progressive ischemic stroke. Logistic analysis was employed in 20 of the studies. Meta-analysis of primary data in the related studies determined that the following factors that significantly correlated with progressive ischemic stroke： fever [risk ratio （RR） = 2.26, 95% confidence interval （CO： 1.20-4.26, P = 0.01; odds ratio （OR） = 2.85, 95% CI： 1.64-4.98, P 〈 0.01 ）]; diabetes （RR = 1.38, 95% CI： 1.18-1.61, P 〈 0.01 ; OR = 2.48, 95% Ch 1.93-3.19, P 〈 0.01 ）; coronary heart disease （RR = 1.22, 95% CI： 1.08-1.38, P 〈 0.01）; neuroimaging transformation （RR= 1.55, 95%CI： 1.34-1.80, P〈 0.01; OR= 2.29, 95% CI： 1.47-3.58, P〈 0.01）; and hyperglycemia （RR = 2.62, 95% CI： 1.86-3.68, P 〈 0.01 ; OR = 3.49, 95% CI： 1.92-6.35, P 〈 0.01）. CONCLUSION： Fever, diabetes, coronary heart disease, neuroimaging transformation,

关键词： systematic review meta-analysis stroke progressive risk factors predictors neural regeneration

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Current Status of Objectification of Four Diagnostic Methods on Constitution Recognition of Chinese Medicine

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Chinese Journal of Integrative Medicine 2022年第12期28卷 1137-1146页

作者： LI Cong-cong YAN Xin-sheng liu ming-hao TENG Gui-fa School of Information Science and Technology Hebei Agricultural UniversityBaodingHebei Province 071001China Hebei Key Laboratory of Agricultural Big Data BaodingHebei Province 071001China

Chinese medicine(CM)has thousands of years of experience in prevention of *** for CM,people's constitution is closely related to their health status,thus recognition of CM constitution is the fundamental and core contentof research on constitution *** development of technologies such as sensors,arificial intelligence and big data,objectification of the four diagnostic methods of CM has gradually matured,bringing changes in the mindset and innovations in technical means for recognition of CM *** paper presents a systematic review of the latest research trends in constitution recognition based on objectification of diagnostic methods in CM.

关键词： Chinese medicine constitution recognition four diagnostic methods objectification machine learning deep learning

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Performance comparison of permafrost models in Wudaoliang Basin,Qinghai-Tibet Plateau,China

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Journal of Mountain Science 2016年第7期13卷 1162-1173页

作者： YIN Guo-an NIU Fu-jun LIN Zhan-ju LUO Jing liu ming-hao State Key Laboratory of Frozen Soils Engineering Cold and Arid Regions Environmental and Engineering Research InstituteChinese Academy of SciencesLanzhou 730000China University of Chinese Academy of Sciences Beijing 100049China

Knowledge of the spatial distribution of permafrost and the effects of climate on ground temperature are important for land use and infrastructure development on the Qinghai-Tibet Plateau(QTP). Different permafrost models have been developed to simulate the ground temperature and active layer thickness(ALT). In this study, Temperature at Top of Permafrost(TTOP) model, Kudryavtsev model and modified Stefan solution were evaluated against detailed field measurements at four distinct field sites in the Wudaoliang Basin to better understand the applicability of permafrost models. Field data from 2012 to 2014 showed that there were notable differences in observed ground temperatures and ALTs within and among the sites. The TTOP model is relatively simple, however, when driven by averaged input values, it produced more accurate permafrost surface temperature(Tps) than the Kudryavtsev model. The modified Stefan solution resulted in a satisfactory accuracy of 90%, which was better than the Kudryavtsev model for estimating ALTs. The modified Stefan solution had the potential of being applied to climate-change studies in the future. Furthermore, additional field investigations over longer periods focusing on hydrology, which has significant influence on permafrost thaw, are necessary. These efforts should employ advanced measurement techniques to obtain adequate and extensive local parameters that will help improve model accuracy.

关键词： Permafrost model Active layer thickness Soil freeze-thaw Soil temperature

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Data-driven spatiotemporal projections of shallow permafrost based on CMIP6 across the Qinghai‒Tibet Plateau at 1 km^(2) scale

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Advances in Climate Change Research 2021年第6期12卷 814-827页

作者： YIN Guo-An NIU Fu-Jun LIN Zhan-Ju LUO Jing liu ming-hao liu State Key Laboratory of Frozen Soils Engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China

The degradation of near-surface permafrost under ongoing climate change on the Qinghai‒Tibet Plateau (QTP) is of growing concern due to its impacts on geomorphological and ecological processes, as well as human activities. There is an increased need for an in-depth understanding of the evolution of permafrost temperature (Ttop) and active-layer thickness (ALT) at a fine scale on the QTP under climate change. This study evaluated the permafrost thermal development over the QTP for the period 1980–2100 at a 1 km^(2) scale using a physically analytical model accounting for both climatic and local environmental factors based on multi-source data. The model results were validated against thermal borehole measurements and baseline maps. The modeled current (2001–2018) permafrost area (Ttop ≤ 0 ℃) covers 1.42 × 10^(6) km^(2) (ca. 56.1% of the QTP land area), 10.1% of which thawed over the historical period 1981–2000. To assess how the ground thermal regime could develop in the future, we utilized the multi-model ensemble mean of downscaled outputs from eight climate models under three Shared Socio-economic Pathways (i.e., SSP126, 245, and 585) in CMIP6 to force the permafrost model. Model results suggest that the current (2001–2018) permafrost extent is likely to dramatically contract in the future period (2021–2100), as indicated by consistent Ttop warming and ALT increasing due to climate changing. About 26.9%, 59.9%, 80.1% of the current permafrost is likely to disappear by the end of the 21st century under SSP126, SSP245, and SSP585 scenarios, respectively. The simulation results may further provide new opportunities to assess the future impacts of climate warming on environments and engineering development over the QTP.

关键词： Climate change Analytical model Permafrost degradation Active-layer CMIP6 Qinghai‒Tibet Plateau(QTP)

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Variations in the northern permafrost boundary over the last four decades in the Xidatan region, Qinghai–Tibet Plateau

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Journal of Mountain Science 2018年第4期15卷 765-778页

作者： LUO Jing NIU Fu-jun LIN Zhan-ju liu ming-hao YIN Guo-an State Key Laboratory of Frozen Soil Engineering Northwest Institute of Eco-Environment and Resources Chinese Academy of Sciences Lanzhou 730000 China South China Institute of Geotechnical Engineering School of Civil Engineering and Transportation South China University of Technology Guangzhou 510641 China

The distribution and variations of permafrost in the Xidatan region, the northern permafrost boundary of the Qinghai-Tibet Plateau, were examined and analyzed using ground penetrating radar(GPR), borehole drilling, and thermal monitoring data. Results from GPR profiles together with borehole verification indicate that the lowest elevation limit of permafrost occurrence is 4369 m above sea level in 2012. Compared to previous studies, the maximal rise of permafrost limit is 28 m from 1975 to 2012. The total area of permafrost in the study region has been decreased by 13.8%. One of the two previously existed permafrost islands has disappeared and second one has reduced by 76% in area during the past ~40 years. In addition, the ground temperature in the Xidatan region has increased from 2012 to 2016, with a mean warming rate of ~0.004℃ a^(-1) and ~0.003℃ a^(-1) at the depths of 6 and 15 m, respectively. The rising of permafrost limit in the Xidatan region is mainly due to globalwarming. However, some non-climatic factors such as hydrologic processes and anthropic disturbances have also induced permafrost degradation. If the air temperature continues to increase, the northern permafrost boundary in the Qinghai-Tibet Plateau may continue rising in the future.

关键词： Qinghai-Tibet Plateau Permafrost Climate warming Permafrost limit Ground penetrating radar Thermal monitoring.

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Porosity of crushed rock layer and its impact on thermal regime of Qinghai-Tibet Railway embankment

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Journal of Central South University 2017年第4期24卷 977-987页

作者： liu ming-hao LI Guo-yu NIU Fu-jun LIN Zhan-ju LIN Zhan-ju State Key Laboratory of Frozen Soil Engineering Cold and Arid Regions Environmental and Engineering Research InstituteChinese Academy of Sciences School of Resources and Environment University of Chinese Academy of Sciences

It has been proven that crushed rock layers used in roadbed construction in permafrost regions have a cooling effect. The main reason is the existence of large porosity of the rock layers. However, due to the strong winds, cold and high radiation conditions on the Qinghai-Tibet Plateau(QTP), both wind-blown sand and/or weathered rock debris blockage might reduce the porosity of the rock layers, resulting in weakening the cooling effect of the crushed rock layer(CRL) in the crushed rock embankment(CRE) of the Qinghai-Tibet Railway(QTR) in the permafrost regions. Such a process might warm the underlying permafrost, and further lead to potential threat to the QTR's integrity and stability. The different porosities corresponding to the different equivalent rock diameters were measured in the laboratory using water saturation method, and an empirical exponential equation between porosity and equivalent rock diameter was proposed based on the measured experimental data and an important finding is observed in our and other experiments that the larger size crushed rock tends to lead to the larger porosity when arbitrarily packing. Numerical tests were carried out to study impacts of porosity on permafrost degradation and differential thaw depths between the sunny and shady shoulders. The results show that the decrease in porosity due to wind-blown sand or weathered rock debris clogging can worsen the permafrost degradation and lead to the asymmetric thermal regime. In the traditional embankment(without the CRL within it), the largest differential thaw depth can reach up to 3.1 m. The optimized porosity appears in a range from 34% to 42% corresponding to equivalent rock diameter from 10 to 20.5 cm. The CRE with the optimized porosities can make underlying permafrost stable and 0 ℃ isotherms symmetric in the coming 50 years, even under the condition that the climate warming can lead to permafrost degradation under the CRE and the traditional embankment. Some practical implica

关键词： Qinghai-Tibet Railway crushed rock embankment porosity wind-blown sand permafrost degradation

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Land potential appraisal for urban land reserve based on GIS: A case of metropolitan area in Chongqing

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重庆邮电大学学报（自然科学版） 2007年第3期19卷 285-289页

作者： liu ming-hao QIU Dao-chi Hae-young Bae School of Resources and Environment Science Southwest University Chongqing 400715 P. R. China School of Computer Science and Technology Chongqing University of Posts and Telecom Chongqing 400065 P. R. China Dept. of Computer Science ＆ Engineering Inha UniversitIncheon 402-751 Korea

With the rapid urbanization, land banking has become an important means for rational land use and land configuration optimizing. Rational urban land reserve and supply plan are keys for an urban land banking. GIS has been used to model urban growth, growth at the rural-urban fringe specifically. This paper identifies that the urban land banking potential can be evaluated based on RS and GIS technology. 10 indicators were chosen in the integrated index system. As a case of Metropolitan area in Chongqing, urban land banking potential was evaluated based on RS and GIS technology. With GIS, two steps can help to finish potential analysis of land banking. One is goal driven process, such as the process of planning and definition; the other step is data-driven process, such as the process of Manipulating. The results are used to establish the current land banking plan.

关键词：城市土地储量地理信息系统重庆陆地勘探估价

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跨座式捷运车辆编组分布式固定时间协同巡航控制

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控制理论与应用 2023年第7期40卷 1296-1303页

作者：刘浩鸣刘朝涛杜子学邬浩鑫侯忠伟重庆交通大学机电与车辆工程学院重庆400074 重庆交通大学交通运输学院重庆400074

为解决跨座式捷运车辆编组协同巡航控制问题,本文提出了基于固定时间理论的跨座式捷运车辆编组分布式协同巡航控制方法.首先,文章建立了跨座式捷运车辆编组动力学模型,明确了编组队列的控制目标,构建了分布式固定时间协同巡航控制架构,... 详细信息

为解决跨座式捷运车辆编组协同巡航控制问题,本文提出了基于固定时间理论的跨座式捷运车辆编组分布式协同巡航控制方法.首先,文章建立了跨座式捷运车辆编组动力学模型,明确了编组队列的控制目标,构建了分布式固定时间协同巡航控制架构,提出了跨座式捷运车辆编组分布式固定时间协同巡航控制方法.然后,本文运用代数图论描述编组间的通讯拓扑关系,应用了分布式固定时间终端滑模估计器估计领航编组的位置和速度,设计了分布式固定时间滑模控制器,并基于Lyapunov稳定性理论证明了控制器的稳定性.最后,文章进行了加速–巡航常规工况仿真实验,验证了所提出控制方法的有效性.

关键词：城市轨道交通跨座式单轨编组队列分布式协同控制固定时间控制滑模控制

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基于双层随机游走的关系推理算法

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计算机学报 2017年第6期40卷 1275-1290页

作者：刘峤韩明皓江浏祎刘瑶耿技电子科技大学信息与软件工程学院成都610054

关系推理是知识库构建的关键技术之一,典型应用场景包括关系预测和实体链接等.关系推理研究的问题是如何利用知识库中已有的知识推理得到新的知识.当前主流知识库采用的推理模型包括潜在因子模型和随机游走模型.前者将实体和关系映射到... 详细信息

关系推理是知识库构建的关键技术之一,典型应用场景包括关系预测和实体链接等.关系推理研究的问题是如何利用知识库中已有的知识推理得到新的知识.当前主流知识库采用的推理模型包括潜在因子模型和随机游走模型.前者将实体和关系映射到一个低维实数向量空间,通过向量相似度计算实现推理.后者基于一阶谓词逻辑进行实体间的关系推理,通过随机算法降低算法复杂度.比较而言,前者由于需要进行大规模矩阵运算而计算复杂度较高,后者则因为采用了随机采样方法,难以完全利用知识库中已有的结构化信息,而导致召回率较低.通过研究现有随机游走模型基本假设存在的问题,提出了两项新的推理建模假设.首先,以PRA为代表的随机游走模型采用关系单向性假设,将知识库中的实体关系三元组视为一阶Horn子句,将关系处理为主语和宾语间的偏序关系,该文提出的假设是,尽管实体间的关系从字面和句法上具有方向性,但关系所包含的信息对两侧实体而言具有语义上的双向性,允许关系推理算法利用从宾语到主语的逆向关系语义进行知识推理;其次,PRA算法采用一阶谓词逻辑进行推理,并通过引入一个随机采样机制来避免穷举搜索和提高计算速度,该文认为这是导致PRA算法及类似算法无法完全利用知识库中已有信息的一个主要原因,据此提出了一个新的假设,即知识库中特定关系子网的拓扑结构所包含的信息可以被利用来改善随机游走模型的关系推理结果,为验证上述假设的有效性,提出了一种基于双层随机游走策略的关系推理新算法,在WN18、FB15K和FB40K等公开数据集上的实验结果表明,该算法能够有效地提高基于随机游走的关系推理模型的准确性和召回率,性能显著优于当前主流的基于潜在因子模型的关系推理算法.

关键词：关系推理统计关系学习知识库扩容随机游走路径排序算法人工智能

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基于动态相量模型的交直流系统混合仿真

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华南理工大学学报（自然科学版） 2006年第10期34卷 83-88页

作者：朱浩骏蔡泽祥刘皓明倪以信华南理工大学电力学院广东广州510640 河海大学电气工程系江苏南京210098 清华大学深圳研究生院广东深圳518055

为了解决高压直流输电(HVDC)系统传统仿真模型的精度问题,提出了一种新的混合模型仿真算法来进行交直流系统的暂态稳定分析,分析中对HVDC采用动态相量模型,对交流系统采用传统机电暂态模型.通过混合仿真研究了HVDC动态相量模型与交流系... 详细信息

为了解决高压直流输电(HVDC)系统传统仿真模型的精度问题,提出了一种新的混合模型仿真算法来进行交直流系统的暂态稳定分析,分析中对HVDC采用动态相量模型,对交流系统采用传统机电暂态模型.通过混合仿真研究了HVDC动态相量模型与交流系统之间的接口迭代算法.算例结果表明,HVDC动态相量模型比电磁暂态模型具有更高的精度,且提出的接口算法能有效地应用于交直流系统的暂态稳定分析.

关键词：混合仿真动态相量暂态稳定高压直流输电

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