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Smart prediction of liquefaction-induced lateral spreading 被引量:1
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作者 Muhammad Nouman Amjad Raja Tarek Abdoun Waleed El-Sekelly 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第6期2310-2325,共16页
The prediction of liquefaction-induced lateral spreading/displacement(Dh)is a challenging task for civil/geotechnical engineers.In this study,a new approach is proposed to predict Dh using gene expression programming(... The prediction of liquefaction-induced lateral spreading/displacement(Dh)is a challenging task for civil/geotechnical engineers.In this study,a new approach is proposed to predict Dh using gene expression programming(GEP).Based on statistical reasoning,individual models were developed for two topographies:free-face and gently sloping ground.Along with a comparison with conventional approaches for predicting the Dh,four additional regression-based soft computing models,i.e.Gaussian process regression(GPR),relevance vector machine(RVM),sequential minimal optimization regression(SMOR),and M5-tree,were developed and compared with the GEP model.The results indicate that the GEP models predict Dh with less bias,as evidenced by the root mean square error(RMSE)and mean absolute error(MAE)for training(i.e.1.092 and 0.815;and 0.643 and 0.526)and for testing(i.e.0.89 and 0.705;and 0.773 and 0.573)in free-face and gently sloping ground topographies,respectively.The overall performance for the free-face topology was ranked as follows:GEP>RVM>M5-tree>GPR>SMOR,with a total score of 40,32,24,15,and 10,respectively.For the gently sloping condition,the performance was ranked as follows:GEP>RVM>GPR>M5-tree>SMOR with a total score of 40,32,21,19,and 8,respectively.Finally,the results of the sensitivity analysis showed that for both free-face and gently sloping ground,the liquefiable layer thickness(T_(15))was the major parameter with percentage deterioration(%D)value of 99.15 and 90.72,respectively. 展开更多
关键词 Lateral spreading Intelligent modeling Gene expression programming(GEP) Closed-form solution Feature importance
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Performance Comparison of Deep and Machine Learning Approaches Toward COVID-19 Detection
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作者 Amani Yahyaoui Jawad Rasheed +4 位作者 Shtwai Alsubai Raed M.Shubair Abdullah Alqahtani Buket Isler Rana Zeeshan Haider 《Intelligent Automation & Soft Computing》 SCIE 2023年第8期2247-2261,共15页
The coronavirus(COVID-19)is a disease declared a global pan-demic that threatens the whole world.Since then,research has accelerated and varied to find practical solutions for the early detection and correct identific... The coronavirus(COVID-19)is a disease declared a global pan-demic that threatens the whole world.Since then,research has accelerated and varied to find practical solutions for the early detection and correct identification of this disease.Several researchers have focused on using the potential of Artificial Intelligence(AI)techniques in disease diagnosis to diagnose and detect the coronavirus.This paper developed deep learning(DL)and machine learning(ML)-based models using laboratory findings to diagnose COVID-19.Six different methods are used in this study:K-nearest neighbor(KNN),Decision Tree(DT)and Naive Bayes(NB)as a machine learning method,and Deep Neural Network(DNN),Convolutional Neural Network(CNN),and Long-term memory(LSTM)as DL methods.These approaches are evaluated using a dataset obtained from the Israelita Albert Einstein Hospital in Sao Paulo,Brazil.This data consists of 5644 laboratory results from different patients,with 10%being Covid-19 positive cases.The dataset includes 18 attributes that characterize COVID-19.We used accuracy,f1-score,recall and precision to evaluate the different developed systems.The obtained results confirmed these approaches’effectiveness in identifying COVID-19,However,ML-based classifiers couldn’t perform up to the standards achieved by DL-based models.Among all,NB performed worst by hardly achieving accuracy above 76%,Whereas KNN and DT compete by securing 84.56%and 85%accuracies,respectively.Besides these,DL models attained better performance as CNN,DNN and LSTM secured more than 90%accuracies.The LTSM outperformed all by achieving an accuracy of 96.78%and an F1-score of 96.58%. 展开更多
关键词 Artificial intelligence COVID-19 deep learning DIAGNOSIS machine learning
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12285例体检者局部脂肪含量与骨密度的相关性研究 被引量:17
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作者 徐君翔 钱志远 +5 位作者 李光飞 张鹏 沈光思 Xi Huang 林华 徐又佳 《中国骨质疏松杂志》 CAS CSCD 北大核心 2014年第8期863-868,共6页
目的了解腰椎周围及髋部周围脂肪比例与骨密度的关系,探讨局部脂肪含量对骨密度检测值的影响。方法收集12285例正常体检人群双能X线骨密度(DEXA)检测的骨密度数据(腰椎和髋部),同时收集每人"骨密度局部模式"所检测的"腰... 目的了解腰椎周围及髋部周围脂肪比例与骨密度的关系,探讨局部脂肪含量对骨密度检测值的影响。方法收集12285例正常体检人群双能X线骨密度(DEXA)检测的骨密度数据(腰椎和髋部),同时收集每人"骨密度局部模式"所检测的"腰椎周围"及"髋部周围"脂肪比例值数据,按照性别、体重指数(BMI)对本组检测人员分组,采用单因素方差分析和多元线性回归统计方法,回顾分析局部脂肪比例与骨密度之间的相关性。结果单因素方差分析:在髋部脂肪比例高的组中,各组骨密度的平均值均较低。男性髋部和腰椎骨密度在腰周脂肪比例高的组别中平均值较高,而女性腰椎骨密度在腰周脂肪比例高的组中平均值较低,髋部的骨密度则没有明显的改变。多元线性回归分析:女性组:骨密度与身高(r=0.276~0.497)和体重(r=0.216~0.526)正相关,与年龄负相关(r=-0.730~-0.454),与髋部周围脂肪比例负相关(r=-0.369~-0.352),与腰椎周围脂肪比例负相关(r=-0.400~-0.245)。在多元回归分析中,控制其他变量后,腰椎骨密度和腰椎周围脂肪比例无统计学上的相关性。腰椎骨密度和髋部周围脂肪比、髋部骨密度和两个部位的脂肪比均呈负相关,并且在BMI高的组中,负相关性较为显著,其中髋部脂肪比和腰椎骨密度负相关性最为显著(r=-0.220~-0.194)。男性组:骨密度与身高(r=0.139~0.388)和体重呈正相关,与年龄相关性差(r=-0.494~0.077),与髋部周围脂肪比例负相关(r=-0.400~-0.216),与腰椎周围脂肪比例负相关(r=-0.329~-0.223)。在多元回归分析中,控制其他变量后,腰椎骨密度和腰椎周围脂肪比例在BMI<20 kg/m2组中呈显著的正相关(r=0.294),在其它组中没有显著的相关性。腰椎骨密度和髋部周围脂肪比、髋部骨密度和两个部位的脂肪比例呈负相关,其中腰椎骨密度和髋部周围脂肪比的负相关性最为显著(r=-0.207~-0.108),并且在BMI低的组中,负相关程度较高。结论脂肪含量对骨密度有显著的影响,局部脂肪比例增加骨密度下降显著(成年女性BMI指数越高相关性越高);脂肪分布对骨密度影响明显,髋部脂肪比(皮下脂肪为主)与腰椎骨密度的负相关性最显著。 展开更多
关键词 骨密度 体质指数 脂肪含量
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甲磺酸去铁胺治疗铁蓄积致骨量下降雄性小鼠的实验研究 被引量:4
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作者 刘禄林 王啸 +8 位作者 李光飞 高超 俞晨 沈光思 张鹏 吴明霞 王爱东 Xi Huang 徐又佳 《中国骨质疏松杂志》 CAS CSCD 北大核心 2015年第1期88-93,共6页
目的观察甲磺酸去铁胺(DFO)干预对铁蓄积导致的小鼠骨量下降骨代谢的治疗作用及其相关机制。方法 32只2月龄雄性小鼠随机分为A、B、C、D 4组,每组8只,A组为对照组(生理盐水干预),B组、C组、D组均运用铁剂腹腔注射干预2月,2月后A、B组处... 目的观察甲磺酸去铁胺(DFO)干预对铁蓄积导致的小鼠骨量下降骨代谢的治疗作用及其相关机制。方法 32只2月龄雄性小鼠随机分为A、B、C、D 4组,每组8只,A组为对照组(生理盐水干预),B组、C组、D组均运用铁剂腹腔注射干预2月,2月后A、B组处死;C组和D组分别再用生理盐水、DFO干预1月后处死;检测血清铁、钙、磷水平,骨转换指标I型胶原C端肽(CTX)、抗酒石酸酸性磷酸酶(TRAP-5b)、骨钙素(BGP)含量,以及氧化应激指标超氧化物歧化酶(SOD)活性、丙二醛(MDA)水平;测定肝脏铁含量,肝脏铁Perls’染色;股骨远端松质骨micro-CT扫描分析和三维重建。结果 1血清铁、肝脏铁含量测定及肝脏Perls’染色示B组铁指标显著高于A组,铁蓄积模型成功建立;DFO干预后D组铁指标显著下降。2血清骨转换指标示B组CTX、Trap-5b显著高于A组,BGP水平低于A组;D组CTX、Trap-5b水平均低于C组,BGP含量高于C组,提示DFO可以部分逆转铁蓄积导致的骨吸收增强和骨形成抑制。3血清氧化应激指标示B组MDA水平高于A组,SOD活性低于A组;D组较C组MDA水平显著降低、SOD升高。4micro-CT示B组较A组骨密度下降,各骨小梁参数减低;而降铁干预1月后D组较对照干预C组各骨参数指标均有改善。结论 DFO可部分逆转铁蓄积导致的骨吸收活性增强和骨形成抑制,从而提高骨密度、改善骨的微结构,其机理可能与降铁改善氧化应激水平有关。 展开更多
关键词 去铁胺 铁蓄积 雄性小鼠 骨量下降
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435名女性体检者血清铁蛋白与骨密度的相关性 被引量:12
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作者 张林林 郑闽前 +8 位作者 徐小卒 刁永力 葛乃航 张鹏 董启榕 钱志远 林华 Huang Xi 徐又佳 《中华骨质疏松和骨矿盐疾病杂志》 2014年第1期9-14,共6页
目的:了解正常女性随年龄增长体内铁含量与骨密度变化的关系,分析铁含量与骨密度的相关性。方法收集2011年1月至2012年12月在苏州大学附属第二医院435名22~80岁体检女性血清铁蛋白和骨密度数据。采用电化学发光法检测血清铁蛋白,采... 目的:了解正常女性随年龄增长体内铁含量与骨密度变化的关系,分析铁含量与骨密度的相关性。方法收集2011年1月至2012年12月在苏州大学附属第二医院435名22~80岁体检女性血清铁蛋白和骨密度数据。采用电化学发光法检测血清铁蛋白,采用双能X线吸收仪测定骨密度。按每5岁为1个年龄段分组,分别统计各组受试者血清铁蛋白和不同部位骨密度的平均值,观察血清铁蛋白、骨密度随年龄变化的情况。将血清铁蛋白按5等分法分类,运用非条件Logistic回归法,分析随血清铁蛋白升高,发生骨量减少风险的变化。采用多元逐步回归分析、偏相关分析法,了解正常女性血清铁蛋白变化与骨密度的相关性。结果女性血清铁蛋白随年龄增加而增加,骨密度随年龄增加而下降,两者变化趋势在围绝经期、绝经期变化显著。骨量减少组(-2.5<T值<-1.0)血清铁蛋白平均值显著高于骨量正常组(P<0.001),骨质疏松组(T值≤-2.5)血清铁蛋白平均值显著高于骨量减少组(P<0.01)和骨量正常组(P<0.001)。校正混杂因素后,血清铁蛋白按5等分法分组,非条件Logistic回归显示血清铁蛋白最高组与最低组相比,股骨颈和腰椎发生骨量减少的OR值(95%CI)分别为2.82(1.25~6.38)和2.04(0.92~4.51),提示随血清铁蛋白增加,骨量减少发生的风险增加。多元逐步回归分析显示,与骨密度变化相关指标为年龄、体重、血清铁蛋白和体重指数( BMI),校正年龄、体重、 BMI、 C反应蛋白( CRP)等混杂因素后,血清铁蛋白与不同部位骨密度均呈显著负相关( P<0.05)。结论随着年龄增长,女性血清铁蛋白逐渐升高、骨密度逐渐下降,二者呈显著负相关。血清铁蛋白增高时,骨量减少、骨质疏松发生率升高。 展开更多
关键词 铁蛋白 铁过载 骨密度 骨质疏松
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Peace Theories & Quest for Peace: A Cross-cultural Perspective
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作者 James C.Hsiung 《International Relations and Diplomacy》 2020年第10期419-425,共7页
Out of the plethora of peace theories,two stand out in particular:(a)the Kantian democratic theory of peace,which argues that peace depends on a league of democracies,and(b)the liberal economic theory of peace,that a ... Out of the plethora of peace theories,two stand out in particular:(a)the Kantian democratic theory of peace,which argues that peace depends on a league of democracies,and(b)the liberal economic theory of peace,that a free,open world market conduces to peace.In this essay,concrete examples are cited that would raise doubt on the validity of these theories.It then proceeds to examine whether culture would make a difference on the incidence of war.In this light,the Westphalian system of states is compared with the historical Chinese“tribute system”qua an inherent system of international relations.One distinct difference is found in the much lower incidence of wars in the latter system,as David Kang’s study identified that in 5 centuries(1368-1841)the Chinese tribute system had only two interstate wars within its circle of members,not counting the wars initiated by external,ex-regional Western powers.And,the religious wars that plagued the West were never found in the Chinese tribute system.In search of an answer to this almost incredible record of low incidence of war,this essay finds that the Confucian culture,with its emphasis on harmony and harmonization of opposites,in contradistinction to the teachings on conflict in Abrahamic cultures,seems to hold the key to an answer.If so,culture,rather than institutions(such as democracies,open world market,etc.)deserves to be seriously considered as a relevant factor contributing to peace.Most importantly,culture as such can be taught and disseminated,including through the classroom. 展开更多
关键词 Democratic Peace long peace Liberal Economic Theory of Peace clash v.harmonization CIVILIZATIONS CULTURES geoeconomics Westphalia System SiniticTribute System
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Neuronal Response to Reward and Luminance in Macaque LIP During Saccadic Choice
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作者 Ziqi Wu Aihua Chen Xinying Cai 《Neuroscience Bulletin》 SCIE CAS CSCD 2023年第1期14-28,共15页
Recent work in decision neuroscience suggests that visual saliency can interact with reward-based choice,and the lateral intraparietal cortex(LIP)is implicated in this process.In this study,we recorded from LIP neuron... Recent work in decision neuroscience suggests that visual saliency can interact with reward-based choice,and the lateral intraparietal cortex(LIP)is implicated in this process.In this study,we recorded from LIP neurons while monkeys performed a two alternative choice task in which the reward and luminance associated with each offer were varied independently.We discovered that the animal’s choice was dictated by the reward amount while the luminance had a marginal effect.In the LIP,neuronal activity corresponded well with the animal’s choice pattern,in that a majority of reward-modulated neurons encoded the reward amount in the neuron’s preferred hemifield with a positive slope.In contrast,compared to their responses to low luminance,an approximately equal proportion of luminance-sensitive neurons responded to high luminance with increased or decreased activity,leading to a much weaker population-level response.Meanwhile,in the non-preferred hemifield,the strength of encoding for reward amount and luminance was positively correlated,suggesting the integration of these two factors in the LIP.Moreover,neurons encoding reward and luminance were homogeneously distributed along the anterior-posterior axis of the LIP.Overall,our study provides further evidence supporting the neural instantiation of a priority map in the LIP in reward-based decisions. 展开更多
关键词 REWARD LUMINANCE Attention Priority map Saccadic choice Lateral intraparietal cortex
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