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贺兰山东麓葡萄酒产区酵母生物多样性研究进展

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现代农业科技 2016年第22期 253-254,256页

作者：王志恒刘雅琴冯翠娥王冲北方民族大学生物科学与工程学院宁夏银川750021

宁夏贺兰山东麓葡萄酒产区是我国著名的葡萄酒产区之一,具有丰富的酵母菌资源。探明贺兰山东麓产区葡萄酒酵母菌的多样性,对贺兰山东麓产区酵母生物多样性研究进行了综合阐述,为选育具有本土特色的优良酵母菌、改善葡萄酒品质、生产具... 详细信息

宁夏贺兰山东麓葡萄酒产区是我国著名的葡萄酒产区之一,具有丰富的酵母菌资源。探明贺兰山东麓产区葡萄酒酵母菌的多样性,对贺兰山东麓产区酵母生物多样性研究进行了综合阐述,为选育具有本土特色的优良酵母菌、改善葡萄酒品质、生产具有地域特色的葡萄酒产品提供研究基础。

关键词：贺兰山东麓葡萄酒产区酵母菌生物多样性

Prediction of electric-powered fixed-wing UAV endurance

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航空动力学报 2017年第9期32卷 2170-2179页

作者： CHeNG feng WANG Hua cui Pin School of Astronautics Beijing University of Aeronautics and Astronautics Science and Technology on Space Physics Laboratory China Academy of Launch Vehicle Technology

To overcome the problems encountered in predicting the endurance of electricpowered fixed-wing unmanned aerial vehicles(UAVs),which were stemmed from the dynamic changes in electric power system efficiency and battery discharge characteristics under different operating conditions,the required battery power model and battery discharge model were *** required battery power model was determined using an approximate model of electric power system efficiency based on wind tunnel testing and the self-adaptive penalty ***,current correction and ambient temperature correction terms were proposed for the trained Kriging model representing the discharge characteristics under standard operation,and then the discharged capacity-terminal voltage model was *** numerical integration of this model with the required battery power model,the electric-powered fixed-wing UAV endurance prediction model was *** tests indicated that the proposed endurance model could precisely calculate the battery discharge time and accurately describe the battery discharge *** similarity of the theoretical and flight test results reflected the accuracy of the proposed endurance model as well as the importance of considering dynamic changes in power system efficiency in endurance *** proposed endurance model meeting precision requirements can be used in practical engineering applications.

关键词： fixed-wing unmanned aerial vehicle(UAV) endurance Peukert equation self-adaptive penalty function power system efficiency

Stable Lagrangian numerical differentiation with the highest order of approximation

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Science China Mathematics 2006年第2期49卷 225-232页

作者： WANG Xinghua cui feng Department of Mathematics Zhejiang University Hangzhou 310028 China Department of Mathematics Zhejiang University Hangzhou 310028 China

Some asymptotic representations for the truncation error for the Lagrangian numerical differentiation are presented, when the ratio of the distance between each interpolation node and the differentiated point to step-parameter h is known. Furthermore, if the sampled values of the function at these interpolation nodes have perturbations which are bounded by ε, a method for determining step-parameter h by means of perturbation bound ε and order n of interpolation is provided to saturate the order of approximation. And all the investigations in this paper can be generalized to the set of quasi-uniform nodes.

关键词： Lagrangian numerical differentiation truncation error stability saturation approximation superconvergence

D DT Theorem over square-free numbers in short interval

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Frontiers of Mathematics in China 2017年第2期12卷 367-375页

作者： Bin feng Zhen cui School of Mathematics Sciences Shanghai Jiao Tong University Shanghai 200240 China College Of Mathematics and Statistics Yangtze Normal University Fuling 408100 China

We study the Cesaro means related to the divisor function. We show that the DDT Theorem holds over square-free numbers in short interval, which generalizes some results established by Deshouillers-Dress-Tenenbaum and ... 详细信息

关键词： Selberg-Delang method arcsine law square-free number

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定窑遗址出土制瓷原料的科学分析

光谱学与光谱分析 2025年第1期45卷 72-81页

作者：陈殿崔剑锋秦大树黄信李鑫北京师范大学历史学院陶瓷考古与艺术研究中心北京100875 考古科学教育部重点实验室(北京大学) 北京100871 浙大城市学院考古学系浙江杭州310015 河北省文物考古研究院河北石家庄050031 中国社会科学院考古研究所北京100101

首次通过窑址发掘出土的制瓷原料,复原了定窑不同时代的胎釉配方。对2009年定窑作坊遗址考古发掘所出五代至宋金时期二十余种制瓷原料开展了eD-XRF成分分析和XRD结构分析等光谱学分析。eD-XRF成分分析显示,这些原料可能包括单一原料和... 详细信息

首次通过窑址发掘出土的制瓷原料,复原了定窑不同时代的胎釉配方。对2009年定窑作坊遗址考古发掘所出五代至宋金时期二十余种制瓷原料开展了eD-XRF成分分析和XRD结构分析等光谱学分析。eD-XRF成分分析显示,这些原料可能包括单一原料和混合原料两种。其中单一原料包括岩石、粘土以及草木灰。混合原料则包括胎料和釉料两种。XRD结构分析表明用于定窑白瓷生产高岭土类原料是含有蒙脱石和方解石的伴生石英的长石类矿物原料。高铁粘土类原料由于铁含量特别高,应当是用于配黑釉的粘土。钙质原料的分析与康葆强等学者对定窑配釉用的灰料可能使用了40%的白灰和60%的松木灰配制的结论相同。同时,还发现了釉灰,即草木煅烧石灰石后形成的混合灰料。在分析定窑白瓷釉时,认为五代的白瓷釉可能使用了釉灰配制,因此定窑釉灰的使用可能推早到五代,这是目前发现使用釉灰配釉最早的实例。对制胎原料XRD晶相分析的结果表明,除了石英和高岭石占主要比重外,还含有长石、蒙脱石、方解石等岩石类矿物。从对单一原料的X射线衍射的分析结果看,石英是粘土以及岩石这类单一原料中都含有的一类矿物,因此可能石英并非必须要添加的胎体原料。石英和高岭石是粘土原料中的主要成分,因此制胎原料应该主要以岩石类原料和粘土作为主要配料。定窑细白瓷胎料可能使用了粘土类原料配合第一类岩石类原料的配方,其配比在金代时大约为1∶1左右,北宋时期可能约为7∶3(粘土∶岩石),五代时大概为6∶4左右。对制釉原料分析结果表明,定窑配釉原料是岩石类原料与釉灰配合形成的,五代、北宋时岩石和灰的比例约为9∶1,金代时石:灰达到了9.5∶0.5。这使得我们对定窑鼎盛时期的白瓷胎釉配方有了更加清晰的了解,从而为开展定窑的复烧提供了确凿的依据。

关键词：定窑制瓷原料光谱学分析

Robust error Density estimation in Ultrahigh Dimensional Sparse Linear Model

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Acta Mathematica Sinica,english Series 2022年第6期38卷 963-984页

作者： feng ZOU Heng Jian cui School of Mathematical Sciences Capital Normal UniversityBeijing 100048P.R.China

This paper focuses on error density estimation in ultrahigh dimensional sparse linear model,where the error term may have a heavy-tailed ***,an improved two-stage refitted crossvalidation method combined with some robust variable screening procedures such as RRCS and variable selection methods such as LAD-SCAD is used to obtain the submodel,and then the residual-based kernel density method is applied to estimate the error density through LAD *** given conditions,the large sample properties of the estimator are also ***,we explicitly give the relationship between the sparsity and the convergence rate of the kernel density *** simulation results show that the proposed error density estimator has a good performance.A real data example is presented to illustrate our methods.

关键词： Ultrahigh dimensional sparse linear model robust density estimation refitted crossvalidation method asymptotic properties

Rotorcraft flight endurance estimation based on a new battery discharge model

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Chinese Journal of Aeronautics 2017年第4期30卷 1561-1569页

作者： feng CHeNG Hua WANG Pin cui School of Astronautics Beihang University Beijing 100083 China Science and Technology on Space Physics Laboratory Beijing 100076 China

To avoid the numerical complexities of the battery discharge law of electric-powered rotorcrafts,this study uses the Kriging method to model the discharge characteristics of Li-Po batteries under standard conditions.A linear current compensation term and an ambient temperature compensation term based on radial basis functions are then applied to the trained Kriging model,leading to the complete discharged capacity-terminal voltage *** an orthogonal experimental design and a sequential method,the coefficients of the current and ambient temperature compensation terms are determined through robust *** endurance calculation model for electric-powered rotorcrafts is then established,based on the battery discharge model,through numerical *** tests show that the maximum relative error of the proposed discharged capacity-terminal voltage model at detection points is 0.0086,and that of the rotorcraft endurance calculation model is 0.0195,thus verifying their accuracy.A flight test further demonstrates the applicability of the proposed endurance model to general electric-powered rotorcrafts.

关键词： Kriging model Orthogonal experimental design Robust optimization Rotorcraft endurance Sequential method

Machine Learning Aided Key-Guessing Attack Paradigm Against Logic Block encryption

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Journal of Computer Science & Technology 2021年第5期36卷 1102-1117页

作者： Yi Zhong Jian-Hua feng Xiao-Xin cui Xiao-Le cui Institute of Microelectronics Peking UniversityBeijing 100871China Key Laboratory of Integrated Microsystems Peking University Shenzhen Graduate SchoolShenzhen 518055China

Hardware security remains as a major concern in the circuit design *** block based encryption has been widely adopted as a simple but effective protection *** this paper,the potential threat arising from the rapidly developing field,i.e.,machine learning,is *** illustrate the challenge,this work presents a standard attack paradigm,in which a three-layer neural network and a naive Bayes classifier are utilized to exemplify the key-guessing attack on logic *** with validation results obtained from both combinational and sequential benchmarks,the presented attack scheme can specifically accelerate the decryption process of partial keys,which may serve as a new perspective to reveal the potential vulnerability for current anti-attack designs.

关键词： hardware security logic encryption machine learning neural network naive Bayes classifier

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不同程度溶血标本对临床化学检测结果的影响

标记免疫分析与临床 2017年第2期24卷 214-217页

作者：李佳吴宗勇陈锋严翠娥高佳齐军国家癌症中心中国医学科学院北京协和医学院肿瘤医院检验科北京100021

目的分析不同程度溶血标本对临床化学检测结果的影响。方法收集血液标本65例,分别对溶血前及溶血后的标本进行临床化学项目的检测,并根据溶血后血红蛋白的含量进行分组,比较不同程度溶血对临床化学项目检测的影响。结果总体来说,钾(K)... 详细信息

目的分析不同程度溶血标本对临床化学检测结果的影响。方法收集血液标本65例,分别对溶血前及溶血后的标本进行临床化学项目的检测,并根据溶血后血红蛋白的含量进行分组,比较不同程度溶血对临床化学项目检测的影响。结果总体来说,钾(K)、丙氨酸氨基转移酶(ALT)、天门冬氨酸氨基转移酶(AST)、乳酸脱氢酶(LDH)、α-羟丁酸脱氢酶(HBDH)、肌酸激酶(CK)、肌酸激酶同工酶(CK-MB)、无机磷(PHOS)、胆固醇(CHOL)、甘油三脂(TG)、铁(Fe)、总蛋白(TP)、前白蛋白(PALB)、超氧化物歧化酶(SOD)、同型半胱氨酸(HCY)溶血后的检测结果明显高于未溶血对照组(P<0.05);二氧化碳(CO2)、γ-谷氨酰转肽酶(GGT)、碱性磷酸酶(ALP)、直接胆红素(DBIL)溶血后的检测结果明显低于未溶血对照组(P<0.05);其余项目两组间比较无明显差异。根据溶血程度分组比较发现,溶血越严重,在临床化学检测项目中受影响的项目数越多。结论标本溶血会对部分临床化学检测结果产生影响,如果进行这些项目的检测应避免使用溶血标本。

关键词：溶血临床化学血红蛋白