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9093. Soft computing and regression modelling approaches for link-capacity functions

Creator:
Kosun, C., Tayfur, G., and Celik, H. M.
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
artificial neural networks, link-capacity functions, regression analysis, travel time, flow rate, and capacity
Language:
English
Description:
Link-capacity functions are the relationships between the fundamental traffic variables like travel time and the flow rate. These relationships are important inputs to the capacity-restrained traffic assignment models. This study investigates the prediction of travel time as a function of several variables V/C (flow rate/capacity), retail activity, parking, number of bus stops and link type. For this purpose, the necessary data collected in Izmir, Turkey are employed by Artificial Neural Networks (ANNs) and Regression-based models of multiple linear regression (MLR) and multiple non-linear regression (MNLR). In ANNs modelling, 70% of the whole dataset is randomly selected for the training, whereas the rest is utilized in testing the model. Similarly, the same training dataset is employed in obtaining the optimal values of the coefficients of the regression-based models. Although all of the variables are used in the input vector of the models to predict the travel time, the most significant independent variables are found to be V/C and retail activity. By considering these two significant input variables, ANNs predicted the travel time with the correlation coefficient R = 0.87 while this value was almost 0.60 for the regression-based models.
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

9094. Soft variable structure control in time-delay systems with saturating input

Creator:
Ignaciuk, Przemysław
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
nonlinear control, time-delay systems, soft Variable Structure Control, and delay compensation
Language:
English
Description:
In order to achieve a short regulation cycle, time-optimal control has been considered in the past. However, the sensitivity to errors and uncertainties, and implementation difficulties in the practical systems, have incited other research directions to meet this objective. In this paper, soft Variable Structure Control (VSC) is analyzed from the perspective of linear time-delay systems with input constraint. The desired fast convergence under a smoothly varying control signal is obtained. The stability issues originating from the non-negligible delay are addressed explicitly by incorporating a dead-time compensator, applicable to both structurally stable and unstable plants. The properties of the obtained dynamic soft VSC system are demonstrated analytically and compared with the linear and saturating control structures.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

9095. Software and hardware realisation of neural network based on Min/Max Nodes for image recognition

Creator:
Holota, R.
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
Neural network, Min/Max nodes, image recognition, face recognition, hardware design, and VHDL
Language:
English
Description:
This article deals with a neural network based on Min/Max nodes and its utilisation for image recognition purposes. The general concepts of the Min/Max nodes and the single-layer neural networks are outlined. The developed software systems for simulation are briefly introduced and the results of simulations with the various settings of a neural net are presented. The subject of simulations was the recognition of human faces. Finally, the hardware design of the neural network in VHDL is shown. The design demonstrates the ease of systems realisation and the achieving of high performance.
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

9097. Soil development on proterozoic and paleozoic rocks of Central Bohemia

Creator:
Žigová, Anna, Šťastný, Martin, and Mikysek, Petr
Format:
print, bez média, and svazek
Type:
model:article and TEXT
Subject:
žuly, jílové minerály, granites, clay minerals, greywacke, mudstone, Leptosols, weddellite, whewellite, 7, and 551
Language:
English
Description:
The character of modern pedogenesis in the territory of the Brdská and Křivoklátská vrchovina Highlands was studied on silicate rocks such as Paleozoic granite and Proterozoic mudstone and greywacke. The parent materials were evaluated on the basis of petrography, X-ray diffractometry of powder samples of rock forming and heavy minerals. The soils were described as for their macromorphological characterics and the results of a variety of analyses of organic and anorganic components. Pedogenesis proceeded in acid conditions. The values of base saturation are mostly below 50 % for the Ah horizons. The intensity of soil development on individual parent material decreases in the order: mudstone (Ah-AhBw-Bw-C)granite (Oi-Oe-Oa-Ah-Bw-C)greywacke 1 (Oi-Oe-Oa-Ah-AhC-C)greywacke 2 (Oi-Oe-Oa-Ah-C). The process of humification was documented at all study sites. Evidence of pedogenetic alteration is present in soils developed on granite and mudstone. High amounts of chlorite and elevated contents of illite are characteristic for Cambic Leptosols (Dystric, Skeletic) on mudstone. Weddellite and whewellite were found in relatively large amounts in O horizons of soils except for the Červený kríž site. The predominant from of calcium oxalate minerals at these sites is whewellite. Weddellite occurs in small amount, which is probably due to its lower stability., Anna Žigová, Martin Šťastný, Petr Mikysek., and Obsahuje bibliografické odkazy
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

9098. Solar excitation of bicentenni al earth rotation oscillations

Creator:
Cyril Ron, Chapanov, Yavor, and Jan Vondrák
Format:
print, bez média, and svazek
Type:
article, články, model:article, and TEXT
Subject:
Geologie. Meteorologie. Klimatologie, zemská rotace, sluneční aktivita, Earth rotation, solar activity, 7, and 551
Language:
English
Description:
The bicentennial varia tions of the Earth rotation consist of several oscill ations with most known periods 178.7a (Jose cycle), 210a and 230a (de Vries cycle); they are driven by the solar cycles which affect climatic variations, followed by global environmental changes. These periods are close to the higher harmonics of millennial Hallstatt cycle (2300a), so the proper separation between the indi vidual bicentennial cycles needs time series longer than 2300a. The bicentennial variations of the Universal Time (UT1) in relation to the Terrestrial Time (TT) are investigated using reconstructed time series of the Total Solar Irradiance (TSI) for the last 9300a. A linear regression model of TSI influe nce on the UT1 and the Mean Sea Level (MSL) bicentennial variations are created. The parameters and time series of the bicentennial UT1-TT oscillations for the last 9300a are determined., Cyril Ron, Yavor Chapanov and Jan Vondrák., and Obsahuje bibliografické odkazy
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

9099. Soluble leptin receptor levels in patients with chronic renal failure

Creator:
Jarmila Křížová, Sylvie Sulková, Vladimíra Bednářová, Jana Pařízková, Eva Kotrlíková, and Martin Haluzík
Format:
print, bez média, and svazek
Type:
article, články, model:article, and TEXT
Subject:
Fyziologie člověka a srovnávací fyziologie, leptin, anorexie, anorexia, soluble leptin receptor, chronic renal failure, 14, and 612
Language:
English
Description:
Soluble leptin receptor (SLR) is the extracellular part of the leptin receptor. This protein is released into circulation and constitutes the main circulating leptin-binding protein. The aim of our study was to measure SLR concentrations in patients with chronic renal failure (CRF) and healthy subjects and to explore the relationship of SLR to other hormones and cytokines. The patients with CRF had significantly higher serum leptin, TNF-a and insulin levels than healthy subjects (25.1±23.5 vs. 9.4±7.6 ng.ml-1 (S.D.); 14.2±4.2 vs. 4.55±2.5 ng.ml-1; 39.8±36.1 vs. 20.3±11.1 mU.l-1). Serum soluble leptin receptor levels did not differ between these groups (19.1±11.3 vs. 19.6±6.1 U.ml-1). An inverse relationship between serum SLR and leptin levels was found in both groups. In patients with CRF the inverse relationship between SLR and insulin, body fat content and total protein levels were also found, while in healthy subjects only inverse relationship of SLR with insulin and albumin concentrations were detected. We conclude that soluble leptin receptor levels in patients with chronic renal failure do not differ from those of healthy subjects despite higher serum leptin levels in CRF patients. The physiological consequences of this finding require further investigation., J. Křížová, S. Sulková, V. Bednářová, E. Kotrlíková, M. Haluzík., and Obsahuje bibliografii
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

9100. Solution of the Neumann problem for the Laplace equation

Creator:
Medková, Dagmar
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
math, single layer potential, and generalized normal derivative
Language:
English
Description:
For fairly general open sets it is shown that we can express a solution of the Neumann problem for the Laplace equation in the form of a single layer potential of a signed measure which is given by a concrete series. If the open set is simply connected and bounded then the solution of the Dirichlet problem is the double layer potential with a density given by a similar series.
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public

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