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1222. A two-stage learning method to configure RBF centers and widths in dynamic environment employing immune operations
- Creator:
- Ling, Xiaofeng, Gong, Xinbao, Zang , Xiaogang, and Ronghong, Jin
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- RBF neural network, dynamics problems, and immune evolutionary mechanism
- Language:
- English
- Description:
- This paper proposes an immunity-based RBF training algorithm for nonlinear dynamic problems. Exploiting the locally-tuned structure of RBF network through immunological metaphor, a two-stage learning technique is proposed to configure RBF centers and widths in the hidden layer. Inspired by affinity maturation process of immune response, immune evolutionary mechanism (IEM) with memory operations is implemented in the learning stages to dynamically fine-tune the network performance. Experiment results also demonstrate that the algorithm has reached good performance with relatively low computational efforts in dynamic environments.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1223. A two-stage stochastic optimization model for a gas sale retailer
- Creator:
- Maggioni, Francesca, Vespucci, Maria Teresa, Allevi, Elisabetta , Bertocchi, Marida, and Innorta, Mario
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- gas sale company, mean reverting process, and stochastic programming
- Language:
- English
- Description:
- The paper deals with a new stochastic optimization model, named OMoGaS-SV (Optimization Modelling for Gas Seller-Stochastic Version), to assist companies dealing with gas retail commercialization. Stochasticity is due to the dependence of consumptions on temperature uncertainty. Due to nonlinearities present in the objective function, the model can be classified as an NLP mixed integer model, with the profit function depending on the number of contracts with the final consumers, the typology of such consumers and the cost supported to meet the final demand. Constraints related to a maximum daily gas consumption, to yearly maximum and minimum consumption in order to avoid penalties and to consumption profiles are included. The results obtained by the stochastic version give clear indication of the amount of losses that may appear in the gas seller's budget and are compared with the results obtained by the deterministic version (see Allevi et al. \cite{ABIV}).
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1224. A two-stage VoIP spam identification framework
- Creator:
- Ebrahim , Gamal A. and Younis, Akmal A:
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- VoIP, SPAM, SIP, SPIT, reputation lists, and fuzzy-logic controller
- Language:
- English
- Description:
- Identifying a VoIP call as SPAM based on call characteristics is an important issue that has never been studied before. Most of the studies of VoIP SPAM impose the whole burden on the callee to judge SPAM calls. In other words, the accuracy of the identification process is totally based on the callee identifying the call as SPAM, which is questionable and not reliable. In this paper, a two-stage VoIP SPAM identification framework is introduced. The first stage is a pre-call identification process, which uses a set of parameters about the call that can be collected before allowing the call to go through. The second stage is a post-call identification process that uses other parameters that can be collected during/after the call. The first stage provides a pre-call evaluation score of the call, while the second stage further tunes this score. In the proposed framework, the decision of identifying VoIP SPAM calls is based on several uncertain parameters that represent meta-data of VoIP calls. These parameters include call duration, amount of exchanged information in each direction, and calling pattern. In this study, the potential set of parameters that can be used to identify VoIP SPAM are investigated. A set of rules is used in addition to any prior evaluation of the caller to provide the pre-call score. Then, a fuzzy-logic controller is developed to identify VoIP SPAM in the second stage. An augmented ongoing tuning strategy is adopted where callee feedback, if any, is taken into account to further tune the identification process. Simulation studies are carried out to demonstrate the effectiveness of the two-stage approach in identifying VoIP SPAM based on the proposed framework.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1225. A unified approach to several inequalities involving functions and derivatives
- Creator:
- Duoandikoetxea, Javier
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- inequalities, averages of functions, and quadrature
- Language:
- English
- Description:
- There are many inequalities measuring the deviation of the average of a function over an interval from a linear combination of values of the function and some of its derivatives. A general setting is given from which the desired inequalities are obtained using Hölder’s inequality. Moreover, sharpness of the constants is usually easy to prove by studying the equality cases of Hölder’s inequality. Comparison of averages, extension to weighted integrals and $n$-dimensional results are also given.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1226. A unique anatomical variation of the vascular supply of the ovary, uterine tube, and uterus from the greater omentum - an anatomical case study
- Creator:
- Kachlík, David, Naňka, Ondřej, Blanková, Alžběta, Turyna, Radovan, Csöbönyeiová, Mária, and Varga, Ivan
- Format:
- počítač and online zdroj
- Type:
- model:article and TEXT
- Subject:
- anatomical vascular variations, internal female genital organs, greater omentum, omental arcade of barkow, uterine artery, and ovarian artery
- Language:
- English
- Description:
- It is well known that the blood supply of the greater omentum and female internal genital organs are not physiologically connected. There is also no mention of such anatomical variation in anatomical, radiological, or surgical textbooks. Here we present a very rare case report of atypical double arterial anastomosis (the first and second variant artery) between the right limb of the omental arcade of Barkow, uterus, and right ovary, which was found during a routine student anatomical dissection course. It is very challenging to find a proper explanation for the presence of the described anatomical variation; however, we hypothesized that it is based on their common embryonic origin - the mesentery. The first and second variant arteries could be remnants of transient anastomoses or collateral circulation, which were present during embryonic development and persisted until adulthood. Moreover, during our literature review, we noticed that the general description of omental blood supply and its possible variations is relatively poor; therefore, we emphasize the need for more precise knowledge regarding these anatomical parts, which could help surgeons who are performing abdominal or pelvic surgeries in preventing avoidable bleeding.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
1227. A value based on marginal contributions for multi-alternative games with restricted coalitions
- Creator:
- Masuya, Satoshi and Inuiguchi, Masahiro
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- game theory, cooperative game, multi-alternative game, restricted game, and Banzhaf value
- Language:
- English
- Description:
- This paper deals with cooperative games with n players and r alternatives which are called multi-alternative games. In the conventional multi-alternative games initiated by Bolger, each player can choose any alternative with equal possibilities. In actual social life, there exist situations in which players have some restrictions on their choice of alternatives. Considering such situations, we study restricted multi-alternative games. A value for a given game is proposed.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1228. A variant of competitive differential evolution algorithm with exponential crossover
- Creator:
- Poláková , Radka
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Global optimization, differential evolution, competition of control parameter settings, and numerical comparison
- Language:
- English
- Description:
- The differential evolution (DE) algorithm is a powerful population-based stochastic technique to search for global optimum in the continuous search space. Success of DE algorithm strongly depends on choosing its parameters. The competition in differential evolution was shown to be an efficient instrument to avoid time-consuming process of tuning control parameters. A new variant of competitive DE algorithm, called BEBERAN, was proposed and tested on benchmark functions at four levels of the search space dimension. The BEBERAN was compared with the most promising competitive variant, DEBR18. BEBERAN, in contrast to DEBR18, includes in addition the exponential crossover.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1229. A versatile scheme for predicting renewal times
- Creator:
- Morvai, Gusztáv and Weiss, Benjamin
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- nonparametric estimation and stationary processes
- Language:
- English
- Description:
- There are two kinds of universal schemes for estimating residual waiting times, those where the error tends to zero almost surely and those where the error tends to zero in some integral norm. Usually these schemes are different because different methods are used to prove their consistency. In this note we will give a single scheme where the average error is eventually small for all time instants, while the error itself tends to zero along a sequence of stopping times of density one.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
1230. A visual object recognition system invariant to scale and rotation
- Creator:
- Sato, Yasuomi D., Jitsev , Jenia, and von der Malsburg, Christoph
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Object recognition, invariance problem, subsystem coordination, and visual processing
- Language:
- English
- Description:
- We address here the problem of scale and rotation invariant object recognition, making use of a correspondence-based mechanism, in which the identity of an object represented by sensory signals is determined by matching it to a representation stored in memory. The sensory representation is in general affected by various transformations, notably scale and rotation, thus giving rise to the fundamental problem of invariant object recognition. We focus here on a neurally plausible mechanism that deals simultaneously with identification of the object and detection of the transformation, both types of information being important for visual processing. Our mechanism is based on macrocolumnar units. These evaluate identity- and transformation-specific feature similarities, performing competitive selection of the alternatives of their own subtask, and cooperate to make a coherent global decision for the identity, scale and rotation of the object.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public