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41.
Juan Carlos Gomez Erik Boiy Marie-Francine Moens 《Knowledge and Information Systems》2012,31(1):23-53
This paper reports on email classification and filtering, more specifically on spam versus ham and phishing versus spam classification,
based on content features. We test the validity of several novel statistical feature extraction methods. The methods rely
on dimensionality reduction in order to retain the most informative and discriminative features. We successfully test our
methods under two schemas. The first one is a classic classification scenario using a 10-fold cross-validation technique for
several corpora, including four ground truth standard corpora: Ling-Spam, SpamAssassin, PU1, and a subset of the TREC 2007
spam corpus, and one proprietary corpus. In the second schema, we test the anticipatory properties of our extracted features
and classification models with two proprietary datasets, formed by phishing and spam emails sorted by date, and with the public
TREC 2007 spam corpus. The contributions of our work are an exhaustive comparison of several feature selection and extraction
methods in the frame of email classification on different benchmarking corpora, and the evidence that especially the technique
of biased discriminant analysis offers better discriminative features for the classification, gives stable classification
results notwithstanding the amount of features chosen, and robustly retains their discriminative value over time and data
setups. These findings are especially useful in a commercial setting, where short profile rules are built based on a limited
number of features for filtering emails. 相似文献
42.
Youssef Bokhabrine Ralph Seulin Lew F. C. Lew Yan Voon Patrick Gorria Gouenou Girardin Miguel Gomez Daniel Jobard 《Machine Vision and Applications》2012,23(3):417-425
During industrial forging of hot metallic shells, it is necessary to regularly measure the dimensions of the parts, especially
the inner and outer diameters and the thickness of the walls. A forging sequence lasts 2 h or more during which the diameter
of the shell is regularly measured in order to decide when to stop the forging process. For better working conditions, for
the safety of the blacksmiths, and for a faster and more accurate measurement, we have developed a novel system based on two
commercially available time of flight laser scanners for the measurement of the diameters of hot cylindrical metallic shells
during the forging process. The advantages of using laser scanners are that they can be placed very far from the hot shell,
more than 15 m, while at the same time giving an accurate point cloud from which three-dimensional views of the shell can
be reconstructed and diameter measurements done. Moreover, more accurate measurement is achieved in less time with the laser
system than with the conventional method using a large ruler. The system has been successfully used to measure the diameters
of hot cylindrical metallic shells. 相似文献
43.
Jose de Jesus Rubio Martin Salazar Angel D. Gomez Raul Lugo 《Neural computing & applications》2012,21(7):1491-1500
The control of the relative humidity and the temperature is important for the birds to be born. It is not easy to control the relative humidity, but it is possible to obtain the measure of the relative humidity as a consequence of the control of the temperature in a bird incubator. In this article, (1) the mathematical model for the control of temperature in the bird incubator is presented, (2) a functional network to approximate the relative humidity behavior in the bird incubator is proposed, (3) a control for the temperature in the bird incubator is proposed, the error of the proportional control applied to the mathematical model of the temperature of the bird incubator is assured to be uniformly stable, (4) the comparison results of four classic control laws for the control of the temperature considering the proposed mathematical model of the temperature and the functional network to approximate the relative humidity behavior in the bird incubator are presented. 相似文献
44.
Agustin Gajate Rodolfo Haber Raul del Toro Pastora Vega Andres Bustillo 《Journal of Intelligent Manufacturing》2012,23(3):869-882
Tool wear detection is a key issue for tool condition monitoring. The maximization of useful tool life is frequently related with the optimization of machining processes. This paper presents two model-based approaches for tool wear monitoring on the basis of neuro-fuzzy techniques. The use of a neuro-fuzzy hybridization to design a tool wear monitoring system is aiming at exploiting the synergy of neural networks and fuzzy logic, by combining human reasoning with learning and connectionist structure. The turning process that is a well-known machining process is selected for this case study. A four-input (i.e., time, cutting forces, vibrations and acoustic emissions signals) single-output (tool wear rate) model is designed and implemented on the basis of three neuro-fuzzy approaches (inductive, transductive and evolving neuro-fuzzy systems). The tool wear model is then used for monitoring the turning process. The comparative study demonstrates that the transductive neuro-fuzzy model provides better error-based performance indices for detecting tool wear than the inductive neuro-fuzzy model and than the evolving neuro-fuzzy model. 相似文献
45.
针对火电厂非线性、多变量和多控制目标的特点,设计了一个火电厂多代理控制系统(PPMACS).在PP MACS中,前馈控制代理(FFCAs)采用神经模糊系统进行决策,反馈控制代理(FBCAs)采用基于遗传算法的模糊系统进行决策.优化任务分解代理(OTDAs)通过一个优化代理和一个分解代理来进行多目标优化分解PPMACS的任务.协调代理根据运行条件协调PPMACS的各个代理.仿真结果显示了火电厂多代理控制系统能够实现火电单元机组的多目标运行和大范围负荷跟踪.神经网络、模糊逻辑和遗传算法是PPMACS中的智能代理进行决策的有效工具. 相似文献
46.
Ratcliff Roger; Thapar Anjali; Gomez Pablo; McKoon Gail 《Canadian Metallurgical Quarterly》2004,19(2):278
The effects of aging on response time (RT) are examined in 2 lexical-decision experiments with young and older subjects (age 60-75). The results show that the older subjects were slower than the young subjects, but more accurate. R. Ratcliff s (1978) diffusion model provided a good account of RTs, their distributions, and response accuracy. The fits show an 80-100-ms slowing of the nondecision components of RT for older subjects relative to young subjects and more conservative decision criterion settings for older subjects than for young subjects. The rates of accumulation of evidence were not significantly different for older compared with young subjects (less than 2% and 5% higher for older subjects relative to young subjects in the 2 experiments). (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
47.
Alejandro Flores-Len Clara Perz Moro Raul Martí Joaquin Beltran Salvador Rosell Jaime Cebolla-Cornejo Belen Pic 《International journal of molecular sciences》2022,23(13)
Spain is a secondary centre of the diversification of the melon (Cucumis melo L.), with high diversity represented in highly appreciated landraces belonging to the Flexuosus and Ibericus groups. A collection of 47 accessions of Flexuosus, Chate, Piel de Sapo, Tendral, Amarillo, Blanco, and Rochet was analysed using a genotyping-by-sequencing (GBS) approach. A total of 66,971 quality SNPs were identified. Genetic analysis differentiated Ibericus accessions and exotic materials (Ameri, Momordica, Kachri, and Agrestis), while Flexuous accessions shared ancestry between them. Within the Ibericus group, no clear genomic distinction could be identified for the different landraces evaluated, with accessions of different landraces showing high genetic similarity. The morphological characterization confirmed that the external colour and fruit shape had been used as recognition patterns for Spanish melon landraces, but variability within a landrace exists. Differences were found in the sugars and acid and volatile profiles of the materials. Flexuosus and Chate melons at the immature commercial stage accumulated malic acid and low levels of hexoses, while Ibericus melons accumulated high contents of sucrose and citric acid. Specific trends could be identified in the Ibericus landraces. Tendral accumulated low levels of sugars and citric acid and high of malic acid, maintaining higher firmness, Rochet reached higher levels of sugars, and Amarillo tended to lower malic acid contents. Interestingly, high variability was found within landraces for the acidic profile, offering possibilities to alter taste tinges. The main volatile organic compounds (VOCs) in Flexuosus and Chate were aldehydes and alcohols, with clear differences between both groups. In the Ibericus landraces, general trends for VOC accumulation could be identified, but, again, a high level of variation exists. This situation highlights the necessity to develop depuration programs to promote on-farm in situ conservation and, at the same time, offers opportunities to establish new breeding program targets and to take advantage of these sources of variation. 相似文献
48.
Henrique J. C. B. Gouveia Mercedes V. Urquiza-Martínez Raul Manhes-de-Castro Brbara J. R. Costa-de-Santana Jos Prez Villarreal Rosalío Mercado-Camargo Luz Torner Jailane de Souza Aquino Ana E. Toscano Omar Guzmn-Quevedo 《International journal of molecular sciences》2022,23(15)
Diets high in bioactive compounds, such as polyphenols, have been used to mitigate metabolic syndrome (MetS). Polyphenols are a large group of naturally occurring bioactive compounds, classified into two main classes: non-flavonoids and flavonoids. Flavonoids are distributed in foods, such as fruits, vegetables, tea, red wine, and cocoa. Studies have already demonstrated the benefits of flavonoids on the cardiovascular and nervous systems, as well as cancer cells. The present review summarizes the results of clinical studies that evaluated the effects of flavonoids on the components of the MetS and associated complications when offered as supplements over the long term. The results show that flavonoids can significantly modulate several metabolic parameters, such as lipid profile, blood pressure, and blood glucose. Only theaflavin and catechin were unable to affect metabolic parameters. Moreover, only body weight and body mass index were unaltered. Thus, the evidence presented in this systematic review offers bases in support of a flavonoid supplementation, held for at least 3 weeks, as a strategy to improve several metabolic parameters and, consequently, reduce the risk of diseases associated with MetS. This fact becomes stronger due to the rare side effects reported with flavonoids. 相似文献
49.
M. Muñoz A. Uyar E. Correia C. Díez A. Fernandez-Gonzalez J.N. Caamaño D. Martínez-Bello B. Trigal P. Humblot C. Ponsart C. Guyader-Joly S. Carrocera D. Martin B. Marquant Le Guienne E. Seli E. Gomez 《Journal of dairy science》2014
We analyzed embryo culture medium (CM) and recipient blood plasma using Fourier transform infrared (FTIR) metabolomics to predict pregnancy outcome. Individually cultured, in vitro-produced (IVP) blastocysts were transferred to recipients as fresh and vitrified-warmed. Spent CM and plasma samples were evaluated using FTIR. The discrimination capability of the classifiers was assessed for accuracy, sensitivity (pregnancy), specificity (nonpregnancy), and area under the receiver operator characteristic curve (AUC). Within all IVP fresh embryos (birth rate = 52%), high AUC were obtained at birth, especially with expanded blastocysts (CM: 0.80 ± 0.053; plasma: 0.89 ± 0.034). The AUC of vitrified IVP embryos (birth rate = 31%) were 0.607 ± 0.038 (CM, expanded blastocysts) and 0.672 ± 0.023 (plasma, all stages). Recipient plasma generally predicted pregnancy outcome better than did embryo CM. Embryos and recipients with improved pregnancy viability were identified, which could increase the economic benefit to the breeding industry. 相似文献
50.