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2382. Assembly neural network with nearest-neighbor recognition algorithm
- Creator:
- Goltsev, Alexander , Húsek, Dušan, and Frolov, Alexander
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Assembly neural network, unsupervised learning, binary Hebbian rule pattern recognition, texture segmentation, and classification
- Language:
- English
- Description:
- An assembly neural network based on the binary Hebbian rule is suggested for pattern recognition. The network consists of several sub-networks according to the number of classes to be recognized. Each sub-network consists of several neural columns according to the dimensionality of the signal space so that the value of each signal component is encoded by activity of adjacent neurons of the column. A new recognition algorithm is presented which realizes the nearest-neighbor method in the assembly neural network. Computer simulation of the network is performed. The model is tested on a texture segmentation task. The experiments have demonstrated that the network is able to segment reasonably real-world texture images.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
2383. Assessing empirical software data with MLP neural networks
- Creator:
- Musilek, Petr and Meltzer, Jason
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Neural networks, software development, effort estimation, model size, accuracy, and evaluation
- Language:
- English
- Description:
- Software measurements provide developers and software managers with information on various aspects of software systems, such as effectiveness, functionality, maintainability, or the effort and cost needed to develop a software system. Based on collected data, models capturing some aspects of software development process can be constructed. A good model should allow software professionals to not only evaluate current or completed projects but also predict future projects with an acceptable degree of accuracy. Artificial neural networks employ a parallel distributed processing paradigm for learning of system and data behavior. Some network models, such as multilayer perceptrons, can be used to build models with universal approximation capabilities. This paper describes an application in which neural networks are used to capture the behavior of several sets of software development related data. The goal of the experiment is to gain an insight into the modeling of software data, and to evaluate the quality of available data sets and some existing conventional models.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
2384. Assessing flow regime alterations in a temporary river - the River Celone case study
- Creator:
- De Girolamo, Anna Maria, Lo Porto, Antonio, Pappagallo, Giuseppe, and Gallart, Francesc
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- natural hydrological regime, temporary stream, hydrological modelling, and indicators of hydrological alteration
- Language:
- Slovak
- Description:
- In this paper, we present an approach to evaluate the hydrological alterations of a temporary river. In these rivers, it is expected that anthropogenic pressures largely modify low-flow components of the flow regime with consequences for aquatic habitat and diversity in invertebrate species. First, by using a simple hydrological index (IARI) river segments of the Celone stream (southern Italy) whose hydrological regime is significantly influenced by anthropogenic activities have been identified. Hydrological alteration has been further classified through the analysis of two metrics: the degree (Mf) and the predictability of dry flow conditions (Sd6). Measured streamflow data were used to calculate the metrics in present conditions (impacted). Given the lack of data from pristine conditions, simulated streamflow time series were used to calculate the metrics in reference conditions. The Soil and Water Assessment Tool (SWAT) model was used to estimate daily natural streamflow. Hydrological alterations associated with water abstractions, point discharges and the presence of a reservoir were assessed by comparing the metrics (Mf, Sd6) before and after the impacts. The results show that the hydrological regime of the river segment located in the upper part of the basin is slightly altered, while the regime of the river segment downstream of the reservoir is heavily altered. This approach is intended for use with ecological metrics in defining the water quality status and in planning streamflow management activities.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
2385. Assessing methods for the estimation of response times of stream discharge: the role of rainfall duration
- Creator:
- Cuevas , Jaime G., Arumi , José L., and Dörner , José
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- empirical equations, lagtimes, semiempirical equations, streamflow, and time of concentration
- Language:
- Slovak
- Description:
- Lagtimes and times of concentration are frequently determined parameters in hydrological design and greatly aid in understanding natural watershed dynamics. In unmonitored catchments, they are usually calculated using empirical or semiempirical equations developed in other studies, without critically considering where those equations were obtained and what basic assumptions they entailed. In this study, we determined the lagtimes (LT) between the middle point of rainfall events and the discharge peaks in a watershed characterized by volcanic soils and swamp forests in southern Chile. Our results were compared with calculations from 24 equations found in the literature. The mean LT for 100 episodes was 20 hours (ranging between 0.6–58.5 hours). Most formulae that only included physiographic predictors severely underestimated the mean LT, while those including the rainfall intensity or stream velocity showed better agreement with the average value. The duration of the rainfall events related significantly and positively with LTs. Thus, we accounted for varying LTs within the same watershed by including the rainfall duration in the equations that showed the best results, consequently improving our predictions. Izzard and velocity methods are recommended, and we suggest that lagtimes and times of concentration must be locally determined with hyetograph-hydrograph analyses, in addition to explicitly considering precipitation patterns.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
2386. Assessing the after-effects of changes in the river flow regime due to different hydrotechnical constructions upon floodplain ecosystems
- Creator:
- Kouzmina, J.V., Treshkin, S.Y., Avetjan, S.A., and Henrichfreise, A.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- regulated river flow, floodplain ecosystem, environment conservation, regulovaný prietok riek, ekosystémy záplavových území, and ochrana životného prostredia
- Language:
- Slovak
- Description:
- The complex environmental research (hydrology, vegetation, soils and ground water) has been carried out in nature reserves, located on the Danube banks within the zone of broad-leaved forests in Germany. Under comparison were terrestrial ecosystems along the regulated and natural rivers. It was established that the weirs, dams with low head of water and small artificial reservoirs affects upon the vegetation and soils of floodplains to be manifested some decades later. A comprehensive analysis of trends in mean annual water level, water flow and the precipitation for the long period revealed the significant influence of natural long-term variability of the water content on the vegetation dynamics in floodplains. The methods, suggested by the authors made possible to assess the after-effects upon floodplain ecosystems due to changes in the river flow regime caused by different hydrotechnical constructions. and V prírodných rezerváciách v blízkosti Dunaja (v Nemecku) v oblasti pokrytej listnatými lesmi bol vykonaný komplexný environmentálny výskum (hydrológia, vegetácia, pôdy a podzemné vody). Porovnávali sa ekosystémy pozdĺž regulovaných a prirodzených tokov. Zistilo sa, že hate a priehrady s relatívne malým vzdutím, ako aj malé vodné nádrže ovplyvňovali vegetáciu a pôdy v záplavových územiach tak, že sa to prejavilo už o niekoľko desaťročí neskôr. Vyčerpávajúca analýza trendov priemernej ročnej výšky hladín, prietokov a zrážok počas dlhého obdobia pomohla objasniť významný vplyv prirodzenej dlhodobej variability obsahu vody na dynamiku vegetácie v zátopových územiach. Metóda navrhnutá autormi umožňuje určiť následné vplyvy zmien vodného režimu tokov spôsobených hydrotechnickými stavbami na ekosystém v záplavovom území.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
2387. Assessing the evolution of learning capabilities and disorders with a graphical exploratory analysis of surveys containing missing and conflicting answers
- Creator:
- Sánchez , Luciano, Couso , Inés, Otero , José , and Palacios , Ana
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Knowledge surveys, graphical exploratory analysis, multidimensional scaling, and fuzzy fitness-based genetic algorithms
- Language:
- English
- Description:
- The analysis of the evolution of learning with graphical maps is based on the placement of the individuals in positions that are computed on the basis of their answers to certain tests. These techniques are useful for detecting similarities between the knowledge profiles of the subjects and can also be used for assessing the acquisition of capabilities after a course. In this paper, we propose to extend some graphical exploratory analysis techniques to the case where there are missing or conflicting answers in the tests. We will also consider that either a missing or unknown answer, or a set of conflictive answers to a survey, is aptly represented by an interval or a fuzzy set. This representation causes that each individual in the map is no longer a point but a figure whose shape and size determine the coherence of the answers and whose position with respect to its neighbors determines the similarities and differences between the individuals.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
2388. Assessing the evolution of learning capabilities and disorders with a graphical exploratory analysis of surveys containing missing nd conflicting answers
- Creator:
- Sánchez-Monedero, J., Hervás-Martínez , C., Gutiérrez , P. A., Ruz, Mariano Carbonero , Ramírez Moreno , M. C. , and Cruz-Ramírez , M.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Accuracy, differential evolution, extreme learning machine, multiclass classification, multiobjective, neural networks, and sensitivity
- Language:
- English
- Description:
- Accuracy alone can be deceptive when evaluating the performance of a classifier, especially if the problem involves a high number of classes. This paper proposes an approach used for dealing with multi-class problems, which tries to avoid this issue. The approach is based on the Extreme Learning Machine (ELM) classifier, which is trained by using a Differential Evolution (DE) algorithm. Two error measures (Accuracy, $C$, and Sensitivity, S) are combined and applied as a fitness function for the algorithm. The proposed approach is able to obtain multi-class classifiers with a high classification rate level in the global dataset with an acceptable level of accuracy for each class. This methodology is evaluated over seven benchmark classification problems and one real problem, obtaining promising results.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
2389. Assessing the relationship between photosynthetic C accumulation and symbiotic N nutrition in leaves of field-grown nodulated cowpea (Vigna unguiculata L. Walp.) genotypes
- Creator:
- Belane, A. K. and Dakora, F. D.
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- fotosyntéza, photosynthesis, N2 fixation, photosynthetic fixed-N use efficiency, transpiration efficiency, δ15N, 2, and 581
- Language:
- Multiple languages
- Description:
- a1_This study evaluated the relationship between photosynthetic carbon accumulation and symbiotic nitrogen nutrition in young fully expanded leaves of 30 nodulated cowpea genotypes grown in the field at Manga, Ghana, in 2005 and 2006. Estimates of fixed-N in photosynthetic leaves revealed greater symbiotic N in genotypes with higher photosynthetic rates and increased leaf transpiration rate/efficiency. There was also greater C accumulation in genotypes with higher symbiotic N and/or total N. Additionally, genotypes with high contents of C per unit of leaf total N exhibited greater C per unit of leaf N-fixed. The C/N and C/Rubisco-N ratios were generally similar in their magnitude when compared to the C/N-fixed ratio due possibly to the fact that Rubisco accounts for a high proportion of photosynthetic leaf N, irrespective of whether the enzyme was formed from soil N or symbiotic N. Cowpea genotypes that relied heavily on soil N for their N nutrition exhibited much higher C/N-fixed ratios, while conversely those that depended more on symbiosis for meeting their N demands showed markedly lower C/N-fixed values. For example, genotypes Omondaw, Bensogla, IT93K-2045-29, and Sanzie, which respectively derived 83.9, 83.1, 82.9, and 76.3% N from fixation, recorded lower C/N-fixed ratios of 10.7, 12.2, 12.1, and 13.0 mg mg-1 in that order in 2005. In contrast, genotypes Botswana White, IT94D-437-1, TVu1509, and Apagbaala, which obtained 14.8, 15.0, 26.4, and 26.0% of their N nutrition from fixation, showed high C/N-fixed values of 84.0, 69.0, 35.2, and 40.6 mg.mg-1, respectively, in 2005., a2_This clearly indicates that genotypes that obtained less N from symbiosis and more N from soil revealed very high C/N-fixed values, an argument that was reinforced by the negative correlations obtained between the three C/N ratios (i.e. C/N, C/Rubisco-N, and C/N-fixed) and leaf N concentration, percentage nitrogen derived from fixation, total N content, amount of N-fixed, and Rubisco N. These data suggest a direct link between photosynthetic C accumulation and symbiotic N assimilation in leaves of nodulated cowpea, and where genotypes derived a large proportion of their N from fixation, photosynthetic C yield substantially increased., A. K. Belane, F. D. Dakora., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
2390. Assessing the retention capacity of a floodplain using a 2D numerical model
- Creator:
- Valentová, Jana, Valenta, Petr, and Weyskrabová, Lenka
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- two-dimensional numerical modeling, floodplain retention capacity, transformation of a flood wave, dvourozměrné numerické modelování, retenční kapacita nivy, and transformace povodňové vlny
- Language:
- Slovak
- Description:
- This paper presents a method for assessing the retention capacity of a floodplain in the course of flooding and for estimating the significance of its water storage for transforming a flood wave. The method is based on two-dimensional numerical modeling of the flood flow in a river channel and in the adjacent floodplains, and is suitable for cases when the morphology of the flooding area is variable and complex, e.g. broad inundation areas with meandering channels. The approach adopted here enables us to quantify the retention capacity for inundation areas of various characters and with various land uses, and provides a tool for estimating the efficiency of possible measures for increasing the water storage capacity of a floodplain. The retention capacity is estimated using an evaluation of a series of detailed flood flow modeling results; the flood wave transformation effect is predicted with the aim of creating a non-linear reservoir model. A parametric study of the floodplain retention capacity for the upper branch of the Lužnice River is presented here, and the results for the current state and for various hypothetical scenarios of changes in geometry and land use are evaluated and compared. and V příspěvku je prezentována metodika pro stanovení retenční kapacity inundačního území při povodňových průtocích a jeho význam pro transformaci povodňové vlny. Metoda využívá dvourozměrný numerický model proudění vody korytem a přilehlým inundačním územím a je vhodná pro případy, kdy charakter nivy je proměnlivý a velmi komplikovaný, např. široká inundační území s meandrujícími toky. Navržený způsob řešení umožňuje kvantifikovat retenční schopnosti niv různého charakteru při různých způsobech využívání a umožňuje případně navrhnout úpravu inundačního území tak, aby transformační účinek při průchodu povodňové vlny byl co největší. Retenční kapacita inundačního území je stanovena na základě výsledků podrobného modelování proudění vody při různých průtokových stavech a transformace povodňové vlny je řešena pomocí iteračního postupu založeného na Bratránkově metodě. V příspěvku je uvedena parametrická studie kvantifikace retenční kapacity nivy na základě vyhodnocení a porovnání transformační schopnosti pro nivu Lužnice v jejím horním úseku pro současný přirozený stav a pro různé teoretické scénáře změněného charakteru a způsobu využívání nivy.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public