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Optimal Receiver Operating Characteristic Curve of Classical Conditional Power under Normal Models
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作者 ZHANG Ying-Ying 《应用概率统计》 北大核心 2025年第2期277-304,共28页
A Receiver Operating Characteristic(ROC)analysis of a power is important and useful in clinical trials.A Classical Conditional Power(CCP)is a probability of a classical rejection region given values of true treatment ... A Receiver Operating Characteristic(ROC)analysis of a power is important and useful in clinical trials.A Classical Conditional Power(CCP)is a probability of a classical rejection region given values of true treatment effect and interim result.For hypotheses and reversed hypotheses under normal models,we obtain analytical expressions of the ROC curves of the CCP,find optimal ROC curves of the CCP,investigate the superiority of the ROC curves of the CCP,calculate critical values of the False Positive Rate(FPR),True Positive Rate(TPR),and cutoff of the optimal CCP,and give go/no go decisions at the interim of the optimal CCP.In addition,extensive numerical experiments are carried out to exemplify our theoretical results.Finally,a real data example is performed to illustrate the go/no go decisions of the optimal CCP. 展开更多
关键词 area under the curve(AUC) classical conditional power(CCP) go/no go decisions historical and interim data receiver operating characteristic(ROC)curve
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Boehmeria nivea var. strigosa (Urticaceae), a new variety from Southwest China 被引量:1
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作者 ZHAO Ying Richard I.MILNE +2 位作者 LI Zhipeng Amos KIPKOECH WU Zengyuan 《广西植物》 CAS CSCD 北大核心 2024年第9期1617-1624,I0001-I0006,共14页
Boehmeria nivea var.strigosa Zeng Y.Wu&Y.Zhao,a new variety of B.nivea(Urticaceae)from Southwest China,is here described based on evidence from morphology and molecular phylogeny.This new variety is mainly charact... Boehmeria nivea var.strigosa Zeng Y.Wu&Y.Zhao,a new variety of B.nivea(Urticaceae)from Southwest China,is here described based on evidence from morphology and molecular phylogeny.This new variety is mainly characterized by its green abaxial leaf blade,partly connate stipules,and densely patent strigose hairs on stems and potioles.The phylogenetic analysis based on rbc L,nrDNA and rbc L+nrDNA datasets,revealed that all individuals of B.nivea var.strigosa formed a monophyletic group.The conservation status of B.nivea var.strigosa is assessed as“Near Threatened”(NT)according to IUCN evaluation criteria.The discovery of this new variety is not only crucial for the taxonomy of ramie,but also provides reference for the exploration and utilization of ramie. 展开更多
关键词 Boehmeria nivea MORPHOLOGY molecular phylogeny new variety Southwest China YUNNAN
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High-resolution CT-scan data reveals the tooth replacement pattern of the Late Jurassic tyrannosauroid Guanlong wucaii (Dinosauria, Theropoda)
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作者 KE Yi-Hui PEI Rui XU Xing 《古脊椎动物学报(中英文)》 CSCD 北大核心 2024年第3期225-244,共20页
The Tyrannosauridae,which is characterized by specialized pachydont dentition and putative bone-cracking predatory strategies,is one of the most extensively studied theropod lineages.Although tooth replacement pattern... The Tyrannosauridae,which is characterized by specialized pachydont dentition and putative bone-cracking predatory strategies,is one of the most extensively studied theropod lineages.Although tooth replacement patterns,crucial for understanding feeding behaviors,have been thoroughly studied in this group,studies on non-tyrannosaurid tyrannosauroids are relatively scarce.This study utilizes high-resolution CT data to investigate the tooth replacement pattern in two specimens of Guanlong wucaii,a Late Jurassic tyrannosauroid,and provides insights into the evolution of tooth replacement across Tyrannosauroidea.Second-generation replacement teeth,a rarity observed mainly in giant predatory theropods(e.g.some tyrannosaurids),were detected in the dentary dentition of the juvenile Guanlong.Zahnreihen reconstructions display a consistent cephalad alternating tooth replacement pattern in the maxilla and the dentary of both of the examined individuals,with Z-spacing values exceeding 2.0.As Guanlong grows,the Z-spacing value in the maxillary dentition increases,resembling the ontogenetic changes documented in the Tyrannosauridae.Additionally,like Tarbosaurus,Guanlong also displays a discontinuity between the tooth replacement waves at the premaxilla-maxilla boundary.This study thus demonstrates that some tyrannosaurid-like tooth replacement patterns were acquired before the origin of the Tyrannosauridae. 展开更多
关键词 Late Jurassic Tyrannosauroidea tooth replacement 3D reconstruction
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Bayesian Influence Assessments in a Growth Curve Model with General Covariance Structure 被引量:2
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作者 BAI PENG PAN JIANXIN FEI YU 《应用概率统计》 CSCD 北大核心 1999年第1期53-62,共10页
The problem considered here is to assess the Bayesian influence on the unknown param-eter matrices in a grwoth curve model with the general covariance structure.Under the non-information prior distribution assumption,... The problem considered here is to assess the Bayesian influence on the unknown param-eter matrices in a grwoth curve model with the general covariance structure.Under the non-information prior distribution assumption,the Kullback-Leibler divergence is employed to eval-uate the effect of a designated response matrix on the posterior distribution of the parameter matrix. 展开更多
关键词 Groveth Curve Model General Covariance Structure Prior and Posterior Dis-tribution Kullback-Leibler Divergence
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SLC-index: A scalable skip list-based index for cloud data processing 被引量:2
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作者 HE Jing YAO Shao-wen +1 位作者 CAI Li ZHOU Wei 《Journal of Central South University》 SCIE EI CAS CSCD 2018年第10期2438-2450,共13页
Due to the increasing number of cloud applications,the amount of data in the cloud shows signs of growing faster than ever before.The nature of cloud computing requires cloud data processing systems that can handle hu... Due to the increasing number of cloud applications,the amount of data in the cloud shows signs of growing faster than ever before.The nature of cloud computing requires cloud data processing systems that can handle huge volumes of data and have high performance.However,most cloud storage systems currently adopt a hash-like approach to retrieving data that only supports simple keyword-based enquiries,but lacks various forms of information search.Therefore,a scalable and efficient indexing scheme is clearly required.In this paper,we present a skip list-based cloud index,called SLC-index,which is a novel,scalable skip list-based indexing for cloud data processing.The SLC-index offers a two-layered architecture for extending indexing scope and facilitating better throughput.Dynamic load-balancing for the SLC-index is achieved by online migration of index nodes between servers.Furthermore,it is a flexible system due to its dynamic addition and removal of servers.The SLC-index is efficient for both point and range queries.Experimental results show the efficiency of the SLC-index and its usefulness as an alternative approach for cloud-suitable data structures. 展开更多
关键词 cloud computing distributed index cloud data processing skip list
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Antibiotic properties of Al_2O_3 doping silver 被引量:1
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作者 张海斌 柳清菊 +2 位作者 朱忠其 张瑾 吴兴惠 《Journal of Central South University of Technology》 2005年第3期263-265,共3页
The preparation technique and properties of Ag-type inorganic antibiotic material carried by Al2O3 were studied. The results show that the material has good antibiotic and safety properties, the acute toxicity taken b... The preparation technique and properties of Ag-type inorganic antibiotic material carried by Al2O3 were studied. The results show that the material has good antibiotic and safety properties, the acute toxicity taken by stomata is LD 50 >8000mg/kg (little and big white rats), and the normal quantity in subacute toxicity test is 80mg/(kg·d). The better mass fraction of doping Ag2O in antibiotic material carried by Al2O3 is 4%CD*28%, and the optimal sintering temperature is from 1000℃ to 1100℃. 展开更多
关键词 CARRIER inorganic antibiotic material Al_2O_3 antibiotic property safety property
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Effects of bias on spin-polarized transport properties in double magnetic tunnel junctions
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作者 LI Yun 《功能材料》 EI CAS CSCD 北大核心 2004年第z1期519-521,共3页
Spin-polarized transport properties in Fe /insulator (Ⅰ) (semiconductor (S)) / Co / I (S) / Fe double junction systems are investigated theoretically, current density is asymmetry as function of the direction of appl... Spin-polarized transport properties in Fe /insulator (Ⅰ) (semiconductor (S)) / Co / I (S) / Fe double junction systems are investigated theoretically, current density is asymmetry as function of the direction of applied bias, and evaluated using generalized formalism base on the non-equilibrium Green's function, which is implemented with calculation of real space Green's function in tight-binding model in linear response region. 展开更多
关键词 SPIN-POLARIZED TRANSPORT magnetic tunneljunction SPIN ACCUMULATION TUNNELING
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Cultural Authenticity and Dynamic Sustainability -- Research on the Exploitation and Protection of Hani Terrace
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作者 Zhao Shuhong 《学术界》 CSSCI 北大核心 2014年第3期292-296,共5页
As the agricultural heritage,Hani terrace is not only culturally authentic and non- renew able,but has its ow n characteristics. Firstly,it is a kind of economic and social mode of production. Secondly,it reflects the... As the agricultural heritage,Hani terrace is not only culturally authentic and non- renew able,but has its ow n characteristics. Firstly,it is a kind of economic and social mode of production. Secondly,it reflects the idea of harmonious and sustainable development betw een human beings and nature. T hirdly,the participation of human beings — or farmers is important. As a result,to exploit and protect the agricultural heritage,it is crucial to balance systematic protection and sustainable development in order to realize dynamic protection. In addition,the agricultural heritage shall be treated as the driving agent to coordinate the social and economic development. T hrough analyzing the characteristics of the agricultural heritage and the concept of protecting the agricultural heritage,this paper proposes to promote the protection of agricultural authenticity by alternative tourism development in order to balance the development and realize the sustainability of the agricultural dynamic system. 展开更多
关键词 开发与保护 可持续性 文化 梯田 可持续发展 人与自然 平衡系统 动态保护
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An Overview of Overseas Interpretation of Socialism with Chinese Characteristics
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作者 Wang Zengzhi 《学术界》 CSSCI 北大核心 2020年第7期193-201,共9页
with the rise of China,how to correctly understand the path of socialism with Chinese characteristics has become a hot issue in the international community.The path of socialism with Chinese characteristics is the pro... with the rise of China,how to correctly understand the path of socialism with Chinese characteristics has become a hot issue in the international community.The path of socialism with Chinese characteristics is the product of the Sinicization of Marxism,and its core point is the leadership of the Communist Party of China.This is the basic perspective to explain this path.From the perspective of the historical process of world modernization,the path of socialism with Chinese characteristics has broken the exclusive situation of Western modernization and provides a new choice for those countries and nations that want to accelerate development while maintain their own independence. 展开更多
关键词 the path of socialism with Chinese characteristics OVERSEAS INTERPRETATION
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"Heaven" and "Man" under the Reconstitution of the Confucianism -- from "Heaven and Man Being Related" to "Heaven and Man Being in One"
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作者 Lin Haitao Ma Ling 《学术界》 CSSCI 北大核心 2015年第2期257-261,共5页
Through analysis of the relationship between heaven and man and the development of the ideology in the developing process from the pre- Qin Confucianism, the cosmology Confucianism of the Han Dynasty to the formation ... Through analysis of the relationship between heaven and man and the development of the ideology in the developing process from the pre- Qin Confucianism, the cosmology Confucianism of the Han Dynasty to the formation of the Confucian School of idealist philosophy of the Song and Ming dynasties, this paper attempts to explore the Confucianism ideology from social structure, cultural integration and environmental change and so on, so as to points out that Confucianism does not collapse with the disintegration of the social structure; instead,it realizes self- reconstruction and renovation. 展开更多
关键词 儒家思想 天人合一 重组 天堂 关联 社会结构 唯心主义 环境变化
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Automatic Segmentation for Intracoronary OCT Image Based on Convolutional Neural Network and Support Vector Machine Methods
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作者 Caining Zhang Huaguang Li +8 位作者 Xiaoya Guo David Molony Xiaopeng Guo Habib Samady Don PGiddens Lambros Athanasiou Rencan Nie Jinde Cao Dalin Tang 《医用生物力学》 EI CAS CSCD 北大核心 2019年第A01期95-96,共2页
Background Cardiovascular diseases are closely associated with atherosclerotic plaque development and rupture.Traditional medical imaging techniques such as magnetic resonance imaging(MRI)and intravascular ultrasound(... Background Cardiovascular diseases are closely associated with atherosclerotic plaque development and rupture.Traditional medical imaging techniques such as magnetic resonance imaging(MRI)and intravascular ultrasound(IVUS)were unable to identify vulnerable plaques due to their limited resolution.Fortunately,optical coherence tomography(OCT)is an advanced intravascular imaging technique developed in recent years which has high resolution approximately 10 microns and could provide more accurate morphology of coronary plaque.In particular,it has the ability to identify plaques with fibrous cap thickness<65μm,an accepted threshold value for vulnerable plaques.However,segmentation of OCT images in clinic is still mainly performed manually by physicians which is time consuming and subjective.To overcome time consumption,several methodologies have been proposed for automatic segmentation of OCT images but most of these methods were still limited by intricate image preprocessing and expensive computation.In this research,two automatic segmentation methods for intracoronary OCT image based on support vector machine(SVM)and convolutional neural network(CNN)were performed to identify the plaque region and characterize plaque components.Methods In vivo IVUS and OCT coronary plaque data from 5 patients were acquired at Emory University with patient’s consent obtained.OCT were obtained from ILUMIEN OPTIS System(St.Jude,Minnesota,MN).The OCT catheter was traversed to the segment of interest and the catheter pullback was limited at a rate of 20 mm/sec.Following the OCT image acquisition,the IVUS catheter was traversed distally though the artery to the same coronary segment(Volcano Therapeutics,Rancho Cordova)and the catheter pullback speed was at a standard rate of 0.5 mm/sec.Seventy-seven matched IVUS and OCT slices with good image quality and lipid cores were selected for our segmentation study.Manual OCT segmentation was performed by experts and used as gold standard in the automatic segmentations.VH-IVUS was used as references and guide by the experts in the manual segmentation process.Three plaque component tissue classes were identified from OCT images in this work:lipid tissue(LT),fibrous tissue(FT)and background(BG).Procedures using two machine learning methods(CNN and SVM)were developed to segment OCT images,respectively.For CNN method,the U-Net architecture was selected due to its good performance in very different biomedical segmentation and very few annotated images.For SVM method,local binary patterns(LBPs),gray level co-occurrence matrices(GLCMs)which contains contrast,correlation,energy and homogeneity,entropy and mean value were calculated as features and assembled to feed SVM classifier.The accuracies of two segmentation methods were evaluated and compared using the OCT dataset.Segmentation accuracy is defined as the ratio of the number of pixels correctly classified over the total number of pixels.Results The overall classification accuracy based CNN method reached 95.8%,and the accuracies for LT,FT and BG were 86.8%,83.4%,and 98.2%,respectively.The overall classification accuracy based SVM was 71.9%,and per-class accuracy for LT,FT and BG was 75.4%,78.3%,and67.0%,respectively.Conclusions The two methods proposed can automatically identify plaque region and characterize plaque compositions for OCT images and potentially reduce the time spent by doctors in segmenting and evaluating coronary plaque OCT images.CNN provided better segmentation accuracies compared to those achieved by SVM. 展开更多
关键词 ATHEROSCLEROTIC PLAQUES OCT CNN SVM image SEGMENTATION
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Cosmic—Ray Deficit from the Directions of the moon and the Sun Detected with the Tibet Air Shower Array 被引量:1
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作者 M.Amenomori Z.Cao +49 位作者 L.K.Ding Z.Y.Feng Hibino N.Hotta Q.Huang A.X.Huo H.Y.Jia G.z.Jiang S.Q.Jiao F.Kajino K.Kasahara Labaciren D.M.Mei L.Meng X.R.Meng Mimaciren K.Mizutani J.Mu H.Nanjo M.Nishizawa Nusang A.Oguro M.Ohnishi I.Ohta To.Saito M.Sakata Z.Z.shi M.Shibata T.Shirai H.Sugimoto X.X.Sun A.Tai K.Taira Y.H.Tan N.Tateyama S.Torii H.Wang C.Z.Wen Y.Yamamoto X.Y.Yao G.C.Yu P.Yuan T.Yuda J.G.Zeng C.S.Zhang H.M.Zhang L.Zhang Zhasang Zhaxiciren W.D.Zhou 《西藏大学学报(社会科学版)》 1993年第4期76-85,共10页
Data from the Tibet air shower array were used to examine the cosmic ray shadows of the Moon and the Sun at energies around 10Tev.The shadowing effect was clearly observed at the 5.8level for the Moon,while the shadow... Data from the Tibet air shower array were used to examine the cosmic ray shadows of the Moon and the Sun at energies around 10Tev.The shadowing effect was clearly observed at the 5.8level for the Moon,while the shadow of the Sun was found in the direction away from the sun by 0.86°tothe west and 0.43°to the south.The effect of the geomagnetic field has also been observed in the shadow of cosmic rays by the Moon.The observed deflection of the sun’s shadow is briefly discussed in connection with the effect of the magnetic fields between the sun and the Earth.This is the first observation of the effects of such magnetic fields on the cosmic ray shadow.The maximum-likelihood analysis of the Moon data set shows that the angular resolutions of the array for showers with its mode energies 7TeVand 35TeV are 0.87°-0.13°+0.10°and 0.54°-0.08°+0.11°,respectively. 展开更多
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