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71.
In this paper, a new approximation to off-line signature verification is proposed based on two-class classifiers using an
expert decisions ensemble. Different methods to extract sets of local and a global features from the target sample are detailed.
Also a normalization by confidence voting method is used in order to decrease the final equal error rate (EER). Each set of
features is processed by a single expert, and on the other approach proposed, the decisions of the individual classifiers
are combined using weighted votes. Experimental results are given using a subcorpus of the large MCYT signature database for
random and skilled forgeries. The results show that the weighted combination outperforms the individual classifiers significantly.
The best EER obtained were 6.3 % in the case of skilled forgeries and 2.31 % in the case of random forgeries. 相似文献
72.
Julián Luengo José A. Sáez Francisco Herrera 《Soft Computing - A Fusion of Foundations, Methodologies and Applications》2012,16(5):863-881
Fuzzy rule-based classification systems (FRBCSs) are known due to their ability to treat with low quality data and obtain
good results in these scenarios. However, their application in problems with missing data are uncommon while in real-life
data, information is frequently incomplete in data mining, caused by the presence of missing values in attributes. Several
schemes have been studied to overcome the drawbacks produced by missing values in data mining tasks; one of the most well
known is based on preprocessing, formerly known as imputation. In this work, we focus on FRBCSs considering 14 different approaches
to missing attribute values treatment that are presented and analyzed. The analysis involves three different methods, in which
we distinguish between Mamdani and TSK models. From the obtained results, the convenience of using imputation methods for
FRBCSs with missing values is stated. The analysis suggests that each type behaves differently while the use of determined
missing values imputation methods could improve the accuracy obtained for these methods. Thus, the use of particular imputation
methods conditioned to the type of FRBCSs is required. 相似文献
73.
Alexandre Petrenko Adenilso Simao José Carlos Maldonado 《International Journal on Software Tools for Technology Transfer (STTT)》2012,14(4):383-386
Model-based testing is focused on testing techniques which rely on the use of models. The diversity of systems and software to be tested implies the need for research on a variety of models and methods for test automation. We briefly review this research area and introduce several papers selected from the 22nd International Conference on Testing Software and Systems (ICTSS). 相似文献
74.
Maria da Graça Marcos J.A. Tenreiro MachadoT.-P. Azevedo-Perdicoúlis 《Applied Soft Computing》2012,12(2):589-599
Kinematic redundancy occurs when a manipulator possesses more degrees of freedom than those required to execute a given task. Several kinematic techniques for redundant manipulators control the gripper through the pseudo-inverse of the Jacobian, but lead to a kind of chaotic inner motion with unpredictable arm configurations. Such algorithms are not easy to adapt to optimization schemes and, moreover, often there are multiple optimization objectives that can conflict between them. Unlike single optimization, where one attempts to find the best solution, in multi-objective optimization there is no single solution that is optimum with respect to all indices. Therefore, trajectory planning of redundant robots remains an important area of research and more efficient optimization algorithms are needed. This paper presents a new technique to solve the inverse kinematics of redundant manipulators, using a multi-objective genetic algorithm. This scheme combines the closed-loop pseudo-inverse method with a multi-objective genetic algorithm to control the joint positions. Simulations for manipulators with three or four rotational joints, considering the optimization of two objectives in a workspace without and with obstacles are developed. The results reveal that it is possible to choose several solutions from the Pareto optimal front according to the importance of each individual objective. 相似文献
75.
Maria Bercea Silvia Ioan Bogdan C. Simionescu Cristofor I. Simionescu 《Polymer Bulletin》1992,27(5):571-575
Summary Systematic studies on solution properties of ultrahigh molecular weight polymers showed the existence of some special features as compared to usual length polymers. The paper discusses the possible appearance of branched structures in the polymerization process, structures able to influence the mentioned features. From experimental data on poly(methyl methacrylate), poly(butyl methacrylate) and polyacrylonitrile it appears that branching can be excluded, and the very high molecular weight domain considered may be responsible for the modifications observed in the molecular weight dependences on 2>, A2 or []. 相似文献
76.
In finite labelled transition systems the problems of deciding strong bisimilarity, observation equivalence and observation congruence areP-complete under many—oneNC-reducibility. As a consequence, algorithms for automated analysis of finite state systems based on bisimulation seem to be inherently sequential in the following sense: the design of anNC algorithm to solve any of these problems will require an algorithmic breakthrough, which is exceedingly hard to achieve. 相似文献
77.
López-Castejón Maria Luisa Hurtado Maria del Carmen de la Fuente Julia Mena Baltasar Bengoechea Carlos 《Iranian Polymer Journal》2021,30(7):723-735
Iranian Polymer Journal - The present work focuses on the assessment of the ability of porcine plasma protein (PPP) to be electrospun satisfactorily to form fibre mats, and their rheological and... 相似文献
78.
Kinga Ciechanowska Maria Pokornowska Anna Kurzyska-Kokorniak 《International journal of molecular sciences》2021,22(2)
Ribonuclease Dicer belongs to the family of RNase III endoribonucleases, the enzymes that specifically hydrolyze phosphodiester bonds found in double-stranded regions of RNAs. Dicer enzymes are mostly known for their essential role in the biogenesis of small regulatory RNAs. A typical Dicer-type RNase consists of a helicase domain, a domain of unknown function (DUF283), a PAZ (Piwi-Argonaute-Zwille) domain, two RNase III domains, and a double-stranded RNA binding domain; however, the domain composition of Dicers varies among species. Dicer and its homologues developed only in eukaryotes; nevertheless, the two enzymatic domains of Dicer, helicase and RNase III, display high sequence similarity to their prokaryotic orthologs. Evolutionary studies indicate that a combination of the helicase and RNase III domains in a single protein is a eukaryotic signature and is supposed to be one of the critical events that triggered the consolidation of the eukaryotic RNA interference. In this review, we provide the genetic insight into the domain organization and structure of Dicer proteins found in vertebrate and invertebrate animals, plants and fungi. We also discuss, in the context of the individual domains, domain deletion variants and partner proteins, a variety of Dicers’ functions not only related to small RNA biogenesis pathways. 相似文献
79.
Irina G. Bryndina Maria N. Shalagina Vladimir A. Protopopov Alexey V. Sekunov Andrey L. Zefirov Guzalia F. Zakirjanova Alexey M. Petrov 《International journal of molecular sciences》2021,22(5)
Muscle disuse and denervation leads to muscle atrophy, but underlying mechanisms can be different. Previously, we have found ceramide (Cer) accumulation and lipid raft disruption after acute hindlimb suspension (HS), a model of muscle disuse. Herein, using biochemical and fluorescent approaches the influence of unilateral denervation itself and in combination with short-term HS on membrane-related parameters of rat soleus muscle was studied. Denervation increased immunoexpression of sphingomyelinase and Cer in plasmalemmal regions, but decreased Cer content in the raft fraction and enhanced lipid raft integrity. Preliminary denervation suppressed (1) HS-induced Cer accumulation in plasmalemmal regions, shown for both nonraft and raft-fractions; (2) HS-mediated decrease in lipid raft integrity. Similar to denervation, inhibition of the sciatic nerve afferents with capsaicin itself increased Cer plasmalemmal immunoexpression, but attenuated the membrane-related effects of HS. Finally, both denervation and capsaicin treatment increased immunoexpression of proapoptotic protein Bax and inhibited HS-driven increase in antiapoptotic protein Bcl-2. Thus, denervation can increase lipid raft formation and attenuate HS-induced alterations probably due to decrease of Cer levels in the raft fraction. The effects of denervation could be at least partially caused by the loss of afferentation. The study points to the importance of motor and afferent inputs in control of Cer distribution and thereby stability of lipid rafts in the junctional and extrajunctional membranes of the muscle. 相似文献
80.
Asher Ornoy Maria Becker Liza Weinstein-Fudim Zivanit Ergaz 《International journal of molecular sciences》2021,22(6)
In spite of the huge progress in the treatment of diabetes mellitus, we are still in the situation that both pregestational (PGDM) and gestational diabetes (GDM) impose an additional risk to the embryo, fetus, and course of pregnancy. PGDM may increase the rate of congenital malformations, especially cardiac, nervous system, musculoskeletal system, and limbs. PGDM may interfere with fetal growth, often causing macrosomia, but in the presence of severe maternal complications, especially nephropathy, it may inhibit fetal growth. PGDM may also induce a variety of perinatal complications such as stillbirth and perinatal death, cardiomyopathy, respiratory morbidity, and perinatal asphyxia. GDM that generally develops in the second half of pregnancy induces similar but generally less severe complications. Their severity is higher with earlier onset of GDM and inversely correlated with the degree of glycemic control. Early initiation of GDM might even cause some increase in the rate of congenital malformations. Both PGDM and GDM may cause various motor and behavioral neurodevelopmental problems, including an increased incidence of attention deficit hyperactivity disorder (ADHD) and autism spectrum disorder (ASD). Most complications are reduced in incidence and severity with the improvement in diabetic control. Mechanisms of diabetic-induced damage in pregnancy are related to maternal and fetal hyperglycemia, enhanced oxidative stress, epigenetic changes, and other, less defined, pathogenic mechanisms. 相似文献