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1.
Motivation: It was found that high accuracy splicing-site recognition of rice (Oryza sativa L.) DNA sequence is especially difficult. We described a new method for the splicing-site recognition of rice DNA sequences. Method: Based on the intron in eukaryotic organisms conforming to the principle of GT-AG, we used support vector machines (SVM) to predict the splicing sites. By machine learning, we built a model and used it to test the effect of the test data set of true and pseudo splicing sites. Results: The prediction accuracy we obtained was 87.53% at the true 5' end splicing site and 87.37% at the true 3' end splicing sites. The results suggested that the SVM approach could achieve higher accuracy than the previous approaches. 相似文献
2.
Peng Si-hua Fan Long-jiang Peng Xiao-ning Zhuang Shu-lin Du Wei Chen Liang-biao 《浙江大学学报(A卷英文版)》2003,4(5):573-577
Motivation: It was found that high accuracy splicing-site recognition of rice (Oryza sativa L.) DNA sequence is especially difficult. We described a new method for the splicing-site recognition of rice DNA sequences.
Method: Based on the intron in eukaryotic organisms conforming to the principle of GT-AG, we used support vector machines
(SVM) to predict the splicing sites. By machine learning, we built a model and used it to test the effect of the test data
set of true and pseudo splicing sites. Results: The prediction accuracy we obtained was 87.53% at the true 5′ end splicing
site and 87.37% at the true 3′ end splicing sites. The results suggested that the SVM approach could achieve higher accuracy
than the previous approaches.
Project partially supported by the Start-up Funding of Zhejiang University to Chen Liang-biao 相似文献
3.
针对目标跟踪中因严重遮挡、变形、快速运动等因素导致的跟踪失败问题,提出一种基于相关滤波的重检测跟踪算法。首先使用相关滤波算法Staple对目标进行位置估计,然后构造一个检测滤波器对Staple算法跟踪结果进行置信度检测,将检测分数作为跟踪结果的置信度评估结果。若检测分数小于给定阈值,则激活在线SVM分类器对跟踪结果进行重检测。同时用检测滤波器对SVM分类结果进行检测,若检测分数大于Staple跟踪算法检测分数,则采用SVM的跟踪结果。在基准数据集OTB-2013上的实验结果表明,该算法精度达到80.2%,成功率达到60.6%,整体性能优于其它6种对比算法。 相似文献
4.
Fault diagnosis of valve clearance in diesel engine based on BP neural network and support vector machine 总被引：1，自引：0，他引：1
Based on wavelet packet transformation(WPT), genetic algorithm(GA), back propagation neural network(BPNN)and support vector machine(SVM), a fault diagnosis method of diesel engine valve clearance is presented. With power spectral density analysis, the characteristic frequency related to the engine running conditions can be extracted from vibration signals. The biggest singular values(BSV)of wavelet coefficients and root mean square (RMS)values of vibration in characteristic frequency sub-bands are extracted at the end of third level decomposition of vibration signals, and they are used as input vectors of BPNN or SVM. To avoid being trapped in local minima, GA is adopted. The normal and fault vibration signals measured in different valve clearance conditions are analyzed. BPNN, GA back propagation neural network (GA-BPNN), SVM and GA-SVM are applied to the training and testing for the extraction of different features, and the classification accuracies and training time are compared to determine the optimum fault classifier and feature selection. Experimental results demonstrate that the proposed features and classification algorithms give classification accuracy of 100%. 相似文献
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6.
为了精确评估个体心理负荷状态,需要获取目标脑电信号数据,脑电信号是评估脑力负荷变化的重要指标。机器学习和神经网络越来越多地用于脑力负荷分类。利用脑电信号特征可在时域和频域中提取突出信息。因此提出一个结合支持向量机（SVM）与超限学习机（ELM）的混合型脑力负荷分类框架。其中支持向量机作为成员分类器,可在高维EEG特征中查找隐藏信息|超限学习机用于融合成员分类器的输出。将ELM-SVM模型与经典脑力负荷分类器进行比较,得出该模型训练精度准确率为1,且测试精度提升0.1个百分点。 相似文献
7.
船体外板复杂曲面自动化加工一直是船舶制造业研究热点和难点,由于加工过程中船板变形影响因素过多,导致船板加工变形预测一直不够准确快速。鉴于此,将两种复合变量用来表征加工过程中热源对应的众多加工参数,采用人工鱼群算法（AFSA）优化的支持向量机（SVM）预测船板变形。经实验验证,复合参数输入的AFSA-SVM模型预测船体外板水火线加热工艺变形线平均精确度为99.87%,角变形平均精确度为99.53%,且全局最优。将其与传统的PSO-SVM模型对比,不仅精确度有了提高,而且避免了局部极值导致的部分预测结果误差过大情况。 相似文献
8.
为了解决传统纸质试卷人工统分过程存在工作量大、错误率高、统分效率低等问题,设计开发一款基于SVM的智能统分自学习系统。该系统由前端用户界面、后台手写分数识别子系统和自学习子系统构成。系统采用C#编程语言和Microsoft Visual Studio软件设计前端用户界面;使用Matlab作为系统运算后台,并构建SVM多分类器识别手写分数;使用C#编程语言设置定时器,在系统空闲时间定时启动Matlab执行自学习程序。经过MNIST数据集的训练和测试,SVM多分类器的测试精度达到97.74%。完成系统设计开发后,使用试卷统分栏图片测试系统。测试结果表明,该系统可以有效实现智能识别、统分栏内手写分数汇总以及自学习功能,并将运行结果清晰准确地显示在前端用户界面上。 相似文献
9.
王晓辉 《韩山师范学院学报》2007,28(3):29-36
最临近支持向量机Proximal SVM(PSVM)是一种有效的、简单的和快速的近似支持向量机方法,识别效果和标准支持向量机相当,相比之下有较少处理时间．虽然有此优点,它的有效性仅仅是针对维数不高、大样本的数据集,而对于上千维甚至上万维的、小样本的人脸数据库情况没有人给出实验结果．文章把PSVM稍做改变,对四个公开的人脸库进行分类．同时采用几种典型的泛化线性鉴别分析(GLDA)方法,对人脸图像预处理．从识别率和所用的处理时间两方面以及用最近邻及最近特征线分类器进行对比,得出具有较好识别效果和处理时间的方法． 相似文献
10.
为了提高电动车铅酸蓄电池的电池荷电状态(SOC)预测精度,将粒子优化算法(PSO)引入到支持向量机(SVM)中,建立了PSO-SVM电动车铅酸蓄电池SOC预测模型,模型输入量为电池的电压和电流,输出量为SOC。采用PSO算法对SVM的惩罚因子C和径向基函数宽度σ寻优,降低了SVM参数取值的盲目性,提高了预测精度。设计了铅酸蓄电池数据智能采集系统,并进行了实际运行车辆电池数据采集。在advisor2002软件中获取的电池数据和实际车辆电池运行数据的基础上,进行了模型训练和预测。结果表明,PSO-SVM预测模型相对传统的BP、RBF和SVM预测模型具有更好的精度和推广能力,满足了"SOC估算精度小于5%"的要求,从而表明该模型是有效的、可行的,并具有较好的工程实用价值。 相似文献
11.
黄酒高产优质技术初探 总被引：2，自引：0，他引：2
以正交试验法为主，对影响黄酒产量及质量的诸多因素进行了综合定量研究.研究结果表明影响黄酒产量的主要因素是用曲，其次是原料，而工艺的影响最小.生产黄酒的最佳条件为以糯米和小米为原料，选用大曲，淀粉酶和小曲为糖化发酵剂，发酵时开耙2～3次，在上述条件下出酒率达82.76%，黄酒品质的感官鉴定结果为优良，理化检验各项指标均达国家标准. 相似文献
12.
《Educational Assessment》2013,18(4):255-258
Editor's Introduction. Reliability Versus Accuracy: A Critical Distinction Test reliability coefficients traditionally have been used to judge the quality of measurement. And, reliability coefficients of .90 have often been considered adequate to assure the quality for standardized testing and large-scale assessment programs. However, a test reliability of .90 (or above) does not ensure that individual test scores, such as national percentile ranks, are accurate. Consider, for example, a mathematics test with a reliability of .90 and imagine a student taking that test whose true score is at the 50th percentile; that is, we know that the student's actual capability is at that level. The probability is less than one third (.309) that when the student takes the test, he or she will obtain a score within 5 percentile points of his or her true score, the 50th percentile (Rogosa 1999a, 1999b). The following informal example attempts to explain why high test reliability does not indicate good accuracy for an individual score, without the encumbrances of percentile rank scoring, complex measurement models, and other technical detail. Dedicated to Al Bundy-A man who cares as much about good measurement as he does about his own children. 相似文献
13.
目前采用地震属性预测储层参数的方法层出不穷,但是这些方法多数是基于单变量、线性的机器学习算法,在已知样本较少的情况下精度得不到保证。为了获取高精度的储层参数,指导油气的勘探开发,迫切需要寻求一种新的方法最大限度地挖掘地震地质信息。支持向量机是以结构风险最小化原则为核心的新型机器学习算法,与传统的机器学习算法相比,其具有基于多变量、小样本、非线性和预测精度高的优点。以渤海湾SZ-361油田Ⅰ油组顶部储层参数预测为例,采用支持向量机算法,得到了较高精度的储层预测结果,证实了支持向量机算法可以应用于油气勘探领域。 相似文献
14.
传统自动柜员机（ATM）监控系统以摄像为主,不能及时检测用户身份是否异常。提出一种基于行为特征的ATM机用户身份实时识别方法,采集用户输入密码时的触屏行为特征数据,通过SVM分类算法判断该用户行为是否属于合法用户。该方法不仅要求用户输入的账户密码正确,还要求该用户的行为特征与预设定的合法用户行为特征一致。实验结果表明,通过数据预处理和SVM分类算法参数优化后的ATM机用户身份识别系统识别精确度达到97.9769%,比没通过数据预处理和SVM分类算法参数优化后的识别精确度高出4.5769%。 相似文献
15.
A two-layer method based on support vector machines （SVMs） has been developed to distinguish epoxide hydrolases （EHs） from other enzymes and to classify its subfamilies using its primary protein sequences. SVM classifiers were built using three different feature vectors extracted from the primary sequence of EHs： the amino acid composition （AAC）, the dipeptide composition （DPC）, and the pseudo-amino acid composition （PAAC）. Validated by 5-fold cross tests, the first layer SVM classifter can differentiate EHs and non-EHs with an accuracy of 94.2% and has a Matthew＇s correlation coefficient （MCC） of 0.84. Using 2-fold cross validation, PAAC-based second layer SVM can further classify EH subfamilies with an overall accuracy of 90.7% and MCC of 0.87 as compared to AAC （80.0%） and DPC （84.9%）. A program called EHPred has also been developed to assist readers to recognize EHs and to classify their subfamilies using primary protein sequences with greater accuracy. 相似文献
16.
Tom Bramley 《Educational research; a review for teachers and all concerned with progress in education》2013,55(3):325-330
Background:?A recent article published in Educational Research on the reliability of results in National Curriculum testing in England (Newton, The reliability of results from national curriculum testing in England, Educational Research 51, no. 2: 181–212, 2009) suggested that: (1) classification accuracy can be calculated from classification consistency; and (2) classification accuracy on a single test administration is higher than classification consistency across two tests. Purpose:?This article shows that it is not possible to calculate classification accuracy from classification consistency. It then shows that, given reasonable assumptions about the distribution of measurement error, the expected classification accuracy on a single test administration is higher than the expected classification consistency across two tests only in the case of a pass–fail test, but not necessarily for tests that classify test-takers into more than two categories. Main argument and conclusion:?Classification accuracy is defined in terms of a ‘true score’ specified in a psychometric model. Three things must be known or hypothesised in order to derive a value for classification accuracy: (1) a psychometric model relating observed scores to true scores; (2) the location of the cut-scores on the score scale; and (3) the distribution of true scores in the group of test-takers. 相似文献
17.
This article presents a method for estimating the accuracy and consistency of classifications based on test scores. The scores can be produced by any scoring method, including a weighted composite. The estimates use data from a single form. The reliability of the score is used to estimate effective test length in terms of discrete items. The true-score distribution is estimated by fitting a 4-parameter beta model. The conditional distribution of scores on an alternate form, given the true score, is estimated from a binomial distribution based on the estimated effective test length. Agreement between classifications on alternate forms is estimated by assuming conditional independence, given the true score. Evaluation of the method showed estimates to be within 1 percentage point of the actual values in most cases. Estimates of decision accuracy and decision consistency statistics were only slightly affected by changes in specified minimum and maximum possible scores. 相似文献
18.
Mapping paddy rice with multi-date moderate-resolution imaging spectroradiometer （MODIS） data in China 总被引：1，自引：0，他引：1
Hua-sheng SUN Jing-feng HUANG Alfredo R. HUETE Dai-liang PENG Feng ZHANG 《浙江大学学报(A卷英文版)》2009,10(10):1509-1522
The objective of this study was to obtain spatial distribution maps of paddy rice fields using multi-date moderateresolution imaging spectroradiometer （MODIS） data in China. Paddy rice fields were extracted by identifying the unique characteristic of high soil moisture in the flooding and transplanting period with improved algorithms based on rice growth calendar regionalization. The characteristic could be reflected by the enhanced vegetation index （EVI） and the land surface water index （LSWI） derived from MODIS sensor data. Algorithms for single, early, and late rice identification were obtained from selected typical test sites. The algorithms could not only separate early rice and late rice planted in the same fields, but also reduce the uncertainties. The areal accuracy of the MODIS-derived results was validated by comparison with agricultural statistics, and the spatial matching was examined by ETM＋ （enhanced thematic mapper plus） images in a test region. Major factors that might cause errors, such as the coarse spatial resolution and noises in the MODIS data, were discussed. Although not suitable for monitoring the inter-annual variations due to some inevitable factors, the MODIS-derived results were useful for obtaining spatial distribution maps of paddy rice on a large scale, and they might provide reference for further studies. 相似文献
19.
为提高工业控制系统入侵检测的准确性,针对工业控制系统应用最广泛的Modbus协议缺陷,采用蜜罐技术将ModbusTCP协议数据包引入蜜罐系统中,研究其在蜜罐系统的活动记录,提取Modbus通信协议特征和蜜罐活动特征。采用核主成分分析法对非线性、高复杂度的Modbus通信行为进行特征优化;针对蜜罐系统中正负样本不平衡特点,采用加权SVM进行有效地精准分类。最后搭建仿真环境,利用Conpot蜜罐模拟工业控制系统场景,通过准确率、误报率和检测时间3个维度对检测方法进行对比。实验结果表明,该方法整体准确率达98.2%,可以应用于工控系统入侵检测,精确判别异常行为。 相似文献
20.
《校园英语(教研版)》2015,(13):252-253
This thesis, following Simone de Beauvoir's c o n c e p t i o n o f " t h e o t h e r ", h o l d s t h a t t h e w o m a n ' s subjectivity can be constructed because woman's subordinate post is the result of the male-dominated culture rather than of the biological difference.These Other manners are namely Eveline's fluid mode of thinking, Mrs.Mooney's soliloquy, she represents her fluid thinking that exhibits the female true existence. 相似文献