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612. A hybrid mean value related to Dedekind sums
- Creator:
- Li, Jianghua and Wenpeng, Zhang
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- the Dedekind sum, hybrid mean value, asymptotic formula, and identity
- Language:
- English
- Description:
- The main purpose of this paper is to study a hybrid mean value problem related to the Dedekind sums by using estimates of character sums and analytic methods.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
613. A hybrid model for business failure prediction -- Utilization of particle swarm optimization and support vector machines
- Creator:
- Chen, Mu-Yen
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Particle swarm optimization, support vector machine, and business failure prediction
- Language:
- English
- Description:
- Bankruptcy has long been an important topic in finance and accounting research. Recent headline bankruptcies have included Enron, Fannie Mae, Freddie Mac, Washington Mutual, Merrill Lynch, and Lehman Brothers. These bankruptcies and their financial fallout have become a serious public concern due to huge influence these companies play in the real economy. Many researchers began investigating bankruptcy predictions back in the early 1970s. However, until recently, most research used prediction models based on traditional statistics. In recent years, however, newly-developed data mining techniques have been applied to various fields, including performance prediction systems. This research applies particle swarm optimization (PSO) to obtain suitable parameter settings for a support vector machine (SVM) model and to select a subset of beneficial features without reducing the classification accuracy rate. Experiments were conducted on an initial sample of 80 electronic companies listed on the Taiwan Stock Exchange Corporation (TSEC). This paper makes four critical contributions: (1) The results indicate the business cycle factor mainly affects financial prediction performance and has a greater influence than financial ratios. (2) The closer we get to the actual occurrence of financial distress, the higher the accuracy obtained both with and without feature selection under the business cycle approach. For example, PSO-SVM without feature selection provides 89.37% average correct cross-validation for two quarters prior to the occurrence of financial distress. (3) Our empirical results show that PSO integrated with SVM provides better classification accuracy than the Grid search, and genetic algorithm (GA) with SVM approaches for companies as normal or under threat. (4) The PSO-SVM model also provides better prediction accuracy than do the Grid-SVM, GA-SVM, SVM, SOM, and SVR-SOM approaches for seven well-known UCI datasets. Therefore, this paper proposes that the PSO-SVM approach could be a more suitable method for predicting potential financial distress.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
614. A hybrid texture analysis system based on non-linear & oriented kernels, particle swarm optimization, and kNN vs. support vector machines
- Creator:
- Peters, Stefanie and Koenig, Andreas
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Texture analysis, design automation, auto-configuration, PSO, and SVM
- Language:
- English
- Description:
- The presented work reports on the progress of our methodology and framework for automated image processing and analysis systém design for industrial vision application. We focus on the important task of automated texture analysis, which is an essential component of automated quality-control systems. In this context, the portfolio of texture operators and assessment methods has been enlarged. Optimized operator parameterization is investigated using particle swarm optimization (PSO). A particular goal of this work is the investigation of support vector machines (SVM) as alternative assessment method for the operator parameter optimization, incorporating the efficient inclusion of SVM parameter settings in this optimization. Methods of the enhanced portfolio were applied employing benchmark textures, real application data from leather inspection, and synthetic textures including defects, specially designed to industrial needs. The key results of our work are that SVM is a highly esteemed and powerful assessment and classification method and parameter optimization, based, e.g., on SVM/PSO of standard and proprietary texture operators boosted performance in all cases. However, the appropriateness of a certain operator proved to be highly data-dependent, which advocates our methodology even more. Thus, the operator selection has been included and investigated for the synthetic textures. Summarising, our work provides a generic texture analysis system, even for unskilled users, that is automatically configured to the application. The method portfolio will be enlarged in future work.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
615. A hybridized neuro-genetic solution for controlling industrial R³ workspace
- Creator:
- Irigoyen , E., Larrea, M., Valera, J., Gómez , V., and Artaza, F.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Hybrid neuro-genetic solution, optimal trajectory generation, multi-objective genetic algorithm, nonlinear neural control, and adaptive predictive control
- Language:
- English
- Description:
- This work presents a hybridized neuro-genetic control solution for R³ workspace application. The solution is based on a multi-objective genetic algorithm reference generator and an adaptive predictive neural network strategy. The trajectory calculation between two points in an R3 workspace is a complex optimization problem considering the fact that there are multiple objectives, restrictions and constraint functions which can play an important role in the problem and be in competition. We solve this problem using genetic algorithms, in a multi objective optimization strategy. Subsequently, we enhance a training algorithm in order to achieve the best adaptation of the neural network parameters in the controller which is responsible for generating the control action for a nonlinear system. As an application of the proposed hybridized control scheme, a crane tracking control is presented.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
616. A hyper-heuristic for adaptive scheduling in Computational Grids
- Creator:
- Xhafa, Fatos
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Hyper-heuristic, scheduling, Grid computing, heuristic methods, immediate mode, batch mode, and Grid simulator
- Language:
- English
- Description:
- In this paper we present the design and implementation of an hyper-heuristic for efficiently scheduling independent jobs in Computational Grids. An efficient scheduling of jobs to Grid resources depends on many parameters, among others, the characteristics of the resources and jobs (such as computing capacity, consistency of computing, workload, etc.). Moreover, these characteristics change over time due to the dynamic nature of Grid environment, therefore the planning of jobs to resources should be adaptively done. Existing ad hoc scheduling methods (batch and immediate mode) have shown their efficacy for certain types of resource and job characteristics. However, as stand alone methods, they are not able to produce the best planning of jobs to resources for different types of Grid resources and job characteristics. In this work we have designed and implemented a hyper-heuristic that uses a set of ad hoc (immediate and batch mode) scheduling methods to provide the scheduling of jobs to Grid resources according to the Grid and job characteristics. The hyper-heuristic is a high level algorithm, which examines the state and characteristics of the Grid system (jobs and resources), and selects and applies the ad hoc method that yields the best planning of jobs. The resulting hyper-heuristic based scheduler can be thus used to develop network-aware applications that need efficient planning of jobs to resources. The hyper-heuristic has been tested and evaluated in a dynamic setting through a prototype of a Grid simulator. The experimental evaluation showed the usefulness of the hyper-heuristic for planning of jobs to resources as compared to planning without knowledge of the resource and job characteristics.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
617. A karyological study of four European species of Roncus (Pseudoscorpiones: Neobisiidae)
- Creator:
- František Šťáhlavský, Christophoryová, Jana, and Henderickx, Hans
- Type:
- article, články, model:article, and TEXT
- Subject:
- Zoologie, zoologie, entomologie, Neobisiidae, pseudoscorpion, Roncus, karyotype evolution, sex chromosomes, meiosis, 2, and 59
- Language:
- English
- Description:
- We present the results of the first study on the karyotypes of four European species of Roncus: Roncus alpinus L. Koch, 1873, Roncus lubricus L. Koch, 1873, Roncus transsilvanicus Beier, 1928 and Roncus sp. The diploid number was 2n = 23 in Roncus sp., 2n = 43 in R. alpinus and R. transsilvanicus and 2n = 45 in R. lubricus. Telocentric autosomes predominate in species with a high chromosome number and metacentric autosomes in Roncus sp. We assume that the ancestral situation for this genus is a high number of chromosomes. A low number of chromosomes is very likely a consequence of centric fusions, which have possibly played a very important role in karyotype evolution in the genus Roncus. All the species analyzed have the X0 sex chromosome system. The X chromosome is metacentric and is the smallest element in the karyotypes of all the species analyzed., František Šťáhlavský, Jana Christophoryova, Hans Henderickx., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
618. A karyotype study on the pseudoscorpion families Geogarypidae, Garypinidae and Olpiidae (Arachnida: Pseudoscorpiones)
- Creator:
- Šťáhlavský, František, Král, Jiří, Harvey, Mark S., and Haddad, Charles R.
- Type:
- article, model:article, and TEXT
- Subject:
- Pseudoscorpiones, Geogarypidae, Garypinidae, Olpiidae, karyotype, sex chromosomes, meiosis, and chiasma frequency
- Language:
- English
- Description:
- The karyotypes of pseudoscorpions of three families, Geogarypidae, Garypinidae and Olpiidae (Arachnida: Pseudoscorpiones), were studied for the first time. Three species of the genus Geogarypus from the family Geogarypidae and 10 species belonging to 8 genera from the family Olpiidae were studied. In the genus Geogarypus the diploid chromosome numbers of males range from 15 to 23. In the family Olpiidae the male chromosome numbers vary greatly, from 7 to 23. The male karyotype of single studied member of the family Garypinidae, Garypinus dimidiatus, is composed of 33 chromosomes. It is proposed that the karyotype evolution of the families Geogarypidae and Olpiidae was characterised by a substantial decrease of chromosome numbers. The diploid numbers of some olpiids are the lowest known 2n within pseudoscorpions and even one of the lowest within the class Arachnida. In spite of a considerable reduction of diploid numbers, all species studied possess a X0 sex chromosome system that is widespread and probably ancestral in pseudoscorpions. Moreover, X chromosomes retain conservative metacentric morphology in the majority of species. During the first meiotic division of males, a high number of chiasmata were observed in some species, up to five per bivalent in Indolpium sp. The transient stage between pachytene and diplotene is typically characterised by extensive decondensation of chromatin in males of geogarypids and in Calocheiridius libanoticus, and we interpret this as a diffuse stage. This is recorded in pseudoscorpions for the first time. The relationships between some species belonging to the family Olpiidae are discussed based on the data obtained.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
619. A key to genera of South American Deltocephalini (Hemiptera: Cicadellidae: Deltocephalinae) with descriptions of new taxa and nomenclatural changes
- Creator:
- Duan, Yani and Dietrich, Christopher H
- Format:
- print, počítač, and online zdroj
- Type:
- model:article and TEXT
- Subject:
- křísi, křískovití, morfologie (biologie), Auchenorrhyncha, Cicadellidae, morphology (biology), Afrika jižní, Africa, Southern, Deltocephalini, taxonomy, key to genera, new taxa, 2, and 59
- Language:
- English
- Description:
- A key to genera of South American Deltocephalini Dallas, 1870 based on adult males is presented. Two new genera, each based on a single new species from Argentina are described and illustrated: Corrientesia gen. n. based on type species C. ochrescens sp. n. and Salnogia gen. n. based on type species S. fletcheri sp. n. A new species of Graminella DeLong, 1936, G. schrocki sp. n. from Argentina is also described and illustrated. Graminella stelliger (Berg, 1884) equals Fusanus acristylus Cheng, 1980, syn. n. A new combination, Limpica pallida (Linnavuori & DeLong, 1979) comb. n., transferred from Reventazonia Linnavuori, 1959, is also proposed. Quaziptus Kramer, 1965, is returned from Paralimnini Distant, 1908 to Deltocephalini Dallas, 1870., Yani Duan, Christopher H. Dietrich., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
620. A knowledge based approach to dynamic route planning
- Creator:
- Eggenkamp , G. and Rothkrantz, L. J. M.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Dynamic routing, knowledge based systems, and artificial intelligence
- Language:
- English
- Description:
- In this paper, an expert system that performs route planning using dynamic traffic data is introduced. Also an algorithmic approach is introduced to find the shortest path in a three-dimensional. Using both implementations, a comparison is made between the expert system approach and the algorithmic approach. It is concluded that the expert system shows great potential. The expert system indeed finds the best routes, and it outperforms the algorithm approach in computation time, too.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public