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PCA与随机森林相结合筛选高信息量SNP位点--应用于羊的品种鉴别 被引量:3
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作者 刘月丽 覃锡忠 +4 位作者 贺三刚 李文蓉 王悦 贾振红 刘明军 《计算机工程与应用》 CSCD 北大核心 2018年第16期235-240,共6页
针对品种鉴别中面临的SNP(Single Nucleotide Polymorphisms)数据高维小样本的难点,研究利用少数高信息量SNP位点正确鉴别品种的方法,提出了一种新的SNP位点筛选方法。先利用PCA提取SNP主要位点,随后使用随机森林方法,根据平均精度下降... 针对品种鉴别中面临的SNP(Single Nucleotide Polymorphisms)数据高维小样本的难点,研究利用少数高信息量SNP位点正确鉴别品种的方法,提出了一种新的SNP位点筛选方法。先利用PCA提取SNP主要位点,随后使用随机森林方法,根据平均精度下降和Gini指数下降对主位点的重要性进行评估,训练分类模型。最后分别选取重要度排名前48和96的位点,以这些位点为分类特征,建立分类模型进行品种鉴别。将该模型应用于6种绵羊Illumina Ovine SNP50的SNP数据。实验表明,可以从46 013个位点中分别筛选出49、96个高信息量位点用于品种鉴别,鉴别准确率达到97%以上。该方法减少了用于品种鉴别的SNP位点个数,降低了品种鉴别成本。 展开更多
关键词 主成分分析(PCA) 随机森林 高信息量SNP位点 品种鉴别
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从第11届亚运会田径竞赛秩序册看竞赛用表的发展方向
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作者 赵玲 《体育成人教育学刊》 1997年第4期43-45,共3页
通过对比传统竞赛用表格与第11届亚运会田径运动会用表格,找出两种表格的差鼻,并预测未来用表的发展方向。
关键词 田径竞赛 传统表格 电子表格 高信息量
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“环肥燕瘦”应相宜
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作者 刘泽平 《新闻知识》 北大核心 1997年第10期39-39,共1页
关键词 新闻写作 高信息量 主题思想 文字表达 新闻稿件 杨玉环 赵飞燕 最大限度 军队 兰州
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RS AND GIS-BASED FOREST FIRE RISK ZONE MAPPING IN DA HINGGAN MOUNTAINS 被引量:2
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作者 YINHai-wei KONGFan-hua LIXiu-Zhen 《Chinese Geographical Science》 SCIE CSCD 2004年第3期251-257,共7页
The Da Hinggan Mountains is one of the most important forest areas in China, but forest fire there is also of high frequency. So it is completely necessary to map forest fire risk zones in order to effectively manage ... The Da Hinggan Mountains is one of the most important forest areas in China, but forest fire there is also of high frequency. So it is completely necessary to map forest fire risk zones in order to effectively manage and protect the forest resources. Two forest farms of Tuqiang Forest Bureau (53 degrees 34'-52 degrees 15'N,124 degrees 05'-122 degrees 18'E) were chosen as typical areas in this study. Remote sensing (RS) and Geographic Information System (GIS) play a vital role and can be used effectively to obtain and combine different forest-fire-causing factors for demarcating the forest fire risk zone map. Forest fire risk zones were described by assigning subjective weights to the classes of all the coverage layers according to their sensitivity to fire, using the ARC/INFO GIS software. Four classes of forest fire risk ranging from low to extremely high were generated automatically in ARC/INFO. The results showed that about 60.33% of the study area were predicted to be upper moderate risk zones, indicating that the forest fire management task in this area is super onerous. The RS and GIS-based forest fire risk model of the study area was found to be highly compatible with the actual fire-affected sites in 1987. Therefore the forest fire risk zone map can be used for guidance of forest fire management, and as basis for fire prevention strategies. 展开更多
关键词 forest fire risk zone RS GIS Da Hinggan Mountains
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Inhomogeneous Shadowing Effect in High-Energy p-A Drell-Yan Process: 被引量:2
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作者 WANG Hong-Min SUN Xian-Jing ZHANG Ben-Ai 《Communications in Theoretical Physics》 SCIE CAS CSCD 2008年第7期175-179,共5页
Having studied the initial state energy loss versus nuclear shadowing for the Drell-Yan dimuon pairproduction in the color string model,the inhomogeneous shadowing effect is considered in this paper.We find thatthe in... Having studied the initial state energy loss versus nuclear shadowing for the Drell-Yan dimuon pairproduction in the color string model,the inhomogeneous shadowing effect is considered in this paper.We find thatthe inhomogeneous shadowing effect does amend the rate of energy loss per unit path length,-dE/dz.Finally,thetheoretical results for the Drell-Yan differential cross-section ratios are compared with the E772 and E866 data.It isfound that the theoretical results are in good agreement with the experimental data. 展开更多
关键词 inhomogeneous shadowing effect color string model Drell Yan process
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Multiparty Quantum Secret Sharing Using Two-Photon Three-Dimensional Bell States 被引量:3
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作者 GAO Gan 《Communications in Theoretical Physics》 SCIE CAS CSCD 2009年第9期421-424,共4页
We present a two-photon three-dimensional multiparty quantum secret sharing scheme.The secret messagesare encoded by performing local operations.This is different from those quantum secret sharing protocols that all s... We present a two-photon three-dimensional multiparty quantum secret sharing scheme.The secret messagesare encoded by performing local operations.This is different from those quantum secret sharing protocols that all sharersmust make a state measurement.The merit of our protocol is the high capacity. 展开更多
关键词 Bell state THREE-DIMENSIONAL quantum secret sharing
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Orthorectification of IKONOS and Impact of Different Resolution DEM 被引量:2
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作者 XU Junfeng HUANG Jingfeng 《Geo-Spatial Information Science》 2006年第2期108-111,共4页
IKONOS image has been wildly used in city planning, precision agriculture and emergence response. However, the accuracy of IKONOS Geo product is limited due to distortion caused by terrain relief. Orthorectification w... IKONOS image has been wildly used in city planning, precision agriculture and emergence response. However, the accuracy of IKONOS Geo product is limited due to distortion caused by terrain relief. Orthorectification was performed to remove the distortion and the impact of different DEM on orthorectification were evaluated. 38 ground control points (GCPs) and 25 independent check points (ICPs) were collected. DEMs were generated from 1∶10 000 and 1∶50 000 topographic maps. Results show that RMS error at the check points is 1.554 0 m using DEM generated from 1∶10 000 topographic map, which can meet the accuracy requirement of IKONOS Precision product (1.9 m RMSE). While RMS error is 2.572 4 m using DEM generated from 1∶50 000 topographic map. 展开更多
关键词 IKONOS orthorectify DEM
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A rate-distortion optimized rate shaping scheme for H.264 data partitioned video bitstream
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作者 张锦锋 《High Technology Letters》 EI CAS 2009年第1期65-69,共5页
To enable quality sealability and further improve the reconstructed video quallty m rate shaping, a rate-distortion optimized packet dropping scheme for H. 264 data partitioned video bitstream is proposed in this pape... To enable quality sealability and further improve the reconstructed video quallty m rate shaping, a rate-distortion optimized packet dropping scheme for H. 264 data partitioned video bitstream is proposed in this paper. Some side information is generated for each video bitstream in advance, while streaming such side information is exploited by a greedy algorithm to optimally drop partitions in a rate-distortion optimized way. Quality sealability is supported by adopting data partition instead of whole frame as the dropping unit. Simulation resuhs show that the proposed scheme achieves a great gain in the reconstructed video quality over two typical frame dropping schemes, with the help of the fine granularity in dropping unit as well as rate-distortion optimization. 展开更多
关键词 rate shaping frame dropping rate-distortion optimization data partition H.264
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Capacity Region of a Class of Gaussian Cognitive Degraded Broadcast Channel
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作者 杨世永 江涛 曹洋 《China Communications》 SCIE CSCD 2013年第10期137-144,共8页
This paper studies the cognitive broadcast channel in which the primary user communicates to the primary receiver, while the secondary user has noncausal knowledge of the primary radio's codeword and expects to co... This paper studies the cognitive broadcast channel in which the primary user communicates to the primary receiver, while the secondary user has noncausal knowledge of the primary radio's codeword and expects to communicate to two secondary receivers. Comparing with the existing cognitive radio channel which considers only one secondary receiver, cognitive broadcast channel studies the case that there are multiple secondary receivers.To this end, we investigate the fundamental limits of the performance of the Gaussian cognitive broadcast channel from the information theoretic perspective. Specifically, we derive the capacity region of the Gaussian cognitive degraded broadcast channel with weak interference. 展开更多
关键词 cognitive radio capacity region broadcast channel dirty paper coding
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A Study on Mixture of Exponentiated Rayleigh and Exponentiated Exponential Distributions Based on Order Statistics
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作者 Rana Ali Mubarak Bakoban 《Journal of Mathematics and System Science》 2012年第3期163-170,共8页
Mixtures of lifetime distributions occur when two different causes of failure arc present, each with the same parametric form of lifetime distributions. This paper is considered with the mixture model of exponentiated... Mixtures of lifetime distributions occur when two different causes of failure arc present, each with the same parametric form of lifetime distributions. This paper is considered with the mixture model of exponentiated Rayleigh and exponentiated exponential distributions. The author's objectives are finding the statistical properties of the model and estimating the parameters of the model by using point estimation and interval estimation methods. First, some properties of the model with some graphs of the density function are discussed. Next, the maximum likelihood method of estimation is used for estimating scale and shape parameters of the model. Estimating the parameters is studied under complete and type II censored samples for different sample sizes. Asymptotic Fisher information matrix of the estimators for complete samples is founded with different sample sizes. The asymptotic variances of the maximum likelihood estimates are derived. Based on the asymptotic variances of the maximum likelihood estimates, interval estimates of the parameters are obtained. Some of the equations in this paper are solved by using numerical iteration such as Newton Raphson method by using Mathematica 7.0. The performance of findings in the paper is showed by demonstrating some numerical illustrations through Monte Carlo simulation study based on absolute relative bias and mean square error. 展开更多
关键词 Exponentiated Rayleigh distribution exponentiated exponential order statistics type-II censoring maximum likelihoodestimator Fisher information matrix.
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Genetic Analysis of Three Populations of Barbados Blackbelly Sheep at Microsatellite Loci
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作者 L. McClean L. Waterman C. Roberts 《Journal of Agricultural Science and Technology(A)》 2011年第8期1187-1191,共5页
The phenotypic traits of high prolificacy, low fat on the rib eye muscle and high tolerance to internal parasites make the Barbados Blackbelly (BBB) sheep a valuable economic resource for small subsistence farmers o... The phenotypic traits of high prolificacy, low fat on the rib eye muscle and high tolerance to internal parasites make the Barbados Blackbelly (BBB) sheep a valuable economic resource for small subsistence farmers on some Caribbean islands. However, the determination of what is a purebred BBB sheep has long been a contentious issue because of the subjectivity. It is therefore necessary to have a more reliable means of identifying what is a purebred BBB sheep for purposes of conservation and breed improvement. Three geographically isolated populations of BBB sheep were genetically analysed at 19 microsatellite loci. Eighteen of the microsatellites were found to be useful for genetic analysis of the BBB sheep, based on polymorphic information content (PIC) values (0.5 〈 PIC 〉 0.25). One microsatellite was not useful for genetic analysis based on PIC (0.111), however it is considered to be a locus of interest because it is fully inbred (f = 1) and homozygous in all of the populations analysed. The analysis also showed that the purebred population of BBB sheep can be distinguished from other populations by formation of distinct clusters when subjected to analysis of molecular variance (AMOVA) and the construction of a rooted consensus tree using the Neighbour-Joining method and pair-wise distances based on marker estimated kinships. 展开更多
关键词 Barbados blackbelly sheep MICROSATELLITE polymorphism information content.
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Evaluation of Skills in Swing Technique in Classical Japanese Swordsmanship in laido Using Sensors
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作者 Satoru Okamoto Satomi Adachi 《Journal of Mechanics Engineering and Automation》 2016年第4期190-196,共7页
In this study, we analyzed the swing motions of more experienced practitioner and new practitioner of iaido players by using tri-axial acceleration sensor and gyro sensor. Iaido is a modern Japanese martial art/sport.... In this study, we analyzed the swing motions of more experienced practitioner and new practitioner of iaido players by using tri-axial acceleration sensor and gyro sensor. Iaido is a modern Japanese martial art/sport. In this way, the acceleration and gyro sensor measurement enabled detailed motion information at the installation points to be displayed in a short time, thus making it possible to easily extract the objective problems. Although it was not possible to confirm by the acceleration and angular velocity measurements the detailed motion of the entire body as obtained in the 2D motion analysis with a high-speed camera, it was confirmed that the acceleration and gyro sensor is an evaluation means that can be installed easily and can provide the exercise information in a short time as an objective index. 展开更多
关键词 Skill science classical Japanese swordsmanship in iaido acceleration sensor high-speed video camera gyro sensor.
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High-capacity quantum secure direct communication with two-photon six-qubit hyperentangled states 被引量:2
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作者 FangZhou Wu GuoJian Yang +4 位作者 HaiBo Wang Jun Xiong Faris Alzahrani Aatef Hobiny FuGuo Deng 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS CSCD 2017年第12期19-25,共7页
This study proposes the first high-capacity quantum secure direct communication(QSDC) with two-photon six-qubit hyperentangled Bell states in two longitudinal momentum and polarization degrees of freedom(DOFs) of phot... This study proposes the first high-capacity quantum secure direct communication(QSDC) with two-photon six-qubit hyperentangled Bell states in two longitudinal momentum and polarization degrees of freedom(DOFs) of photon pairs, which can be generated using two 0.5 mm-thick type-I β barium borate crystal slabs aligned one behind the other and an eight-hole screen. The secret message can be independently encoded on the photon pairs with 64 unitary operations in all three DOFs. This protocol has a higher capacity than previous QSDC protocols because each photon pair can carry 6 bits of information, not just 2 or 4 bits.Our QSDC protocol decreases the influence of decoherence from environment noise by exploiting the decoy photons to check the security of the transmission of the first photon sequence. Compared with two-way QSDC protocols, our QSDC protocol is immune to an attack by an eavesdropper using Trojan horse attack strategies because it is a one-way quantum communication.The QSDC protocol has good applications in the future quantum communication because of all these features. 展开更多
关键词 quantum secure direct communication high capacity hyperentanglement two-photon six-qubit systems decoy photons
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