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28902. Perforace pravé komory způsobené stimulační elektrodou
- Creator:
- Vlašínová, Jitka
- Type:
- model:article, article, Text, kazuistiky, and TEXT
- Subject:
- kardiostimulace umělá, defibrilátory implantabilní, perikardiální efúze--etiologie--radioizotopová diagnostika, kardiostimulátor--využití, elektrody implantované--statistika a číselné údaje, pooperační komplikace, srdeční komory--zranění, penetrující rány--etiologie--chirurgie, lidé, and staří
- Language:
- Czech and English
- Description:
- Perforace pravé komory stimulační nebo defibrilační elektrodou je známo u komplikací trvalé kardiostimulace. V našem sdělení prezentujeme tři kazuistiky pacientů, kteří se liší dobou vzniku peforace od primo implantace, klinickými projevy a terape utickými postupy., Perforati on of the right ventricle by a stimulation or defibrillation electrode is a known complicati on of permanent cardiac stimulation. The article presents three case histories of patients who differ in terms of the length of time from initial implantation to the occurrence of perforation, clinical effects and therape utic strategies., Jitka Vlašínová, and Lit.: 7
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
28903. Performance characteristics of the APTIMA® HPV assay for detection of high risk HPVtTypes in surepath liquid-based cervical cytology specimens
- Creator:
- Valsamakis, Alexandra
- Type:
- model:article and TEXT
- Language:
- English
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
28904. Performance comparison of artificial intelligence methods for predicting cash flow
- Creator:
- Hongjiu, Liu, Rieg, Robert, and Yanrong, Hu
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Performance, prediction, and cash flow
- Language:
- English
- Description:
- Cash flow forecasting is indispensable for managers, investors and banks. However, which method is more robust has been argued under the condition of small size samples. With sliding window technique we create the Response Surface, Back Propagation Neural Network, Radial Basis Functions Neural Network and Support Vector Machine models respectively, which are examined by comparing performances of training and simulation. Performances of training models are measured by mean of squared errors while that of simulation is done by average relative errors of the results. By comparison, Support Vector Machine is most robust to forecast cash flow, followed by Radial Basis Function Neural Network, the third Back Propagation Neural Network and the last Response Surface Model. The optimal result of each model depends on the window size of the transmitter.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
28905. Performance comparison of least squares, iterative and global L1 norm minimization and exhaustive search methods for outlier detection in leveling networks
- Creator:
- Baselga, Sergio, Klein, Ivandro, Sampaio Suraci, Stefano, de Oliveir, aLeonardo Castro, Matsuoka, Marcelo, and Rofatto, Vinicius Francisco
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- geodetic networks, leveling, robust estimation, and outlier detection
- Language:
- English
- Description:
- Different approaches have been proposed to determine the possible outliers existing in a dataset. The most widely used consists in the application of the data snooping test over the least squares adjustment results. This strategy is very likely to succeed for the case of zero or one outliers but, contrary to what is often assumed, the same is not valid for the multiple outlier case, even in its iterative application scheme. Robust estimation, computed by iteratively reweighted least squares or a global optimization method, is other alternative approach which often produces good results in the presence of outliers, as is the case of exhaustive search methods that explore elimination of every possible set of observations. General statements, having universal validity, about the best way to compute a geodetic network with multiple outliers are impossible to be given due to the many different factors involved (type of network, number and size of possible errors, available computational force, etc.). However, we see in this paper that some conclusions can be drawn for the case of a leveling network, which has a certain geometrical simplicity compared with planimetric or three-dimensional networks though a usually high number of unknowns and relatively low redundancy. Among other results, we experience the occasional failure in the iterative application of the data snooping test, the relatively successful results obtained by both methods computing the robust estimator, which perform equivalently in this case, and the successful application of the exhaustive search method, for different cases that become increasingly intractable as the number of outliers approaches half the number of degrees of freedom of the network.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
28906. Performance comparison of multilayer perceptrons and support vector machines in a short-term wind speed prediction problem
- Creator:
- Salcedo Sanz , S., Ortiz-García, E. G., Pérez-Bellido, Á. M., Portilla-Figueras, A., Prieto, L., Paredes, D., and Correoso, F.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Wind speed forecast, global forecasting models, down-scaling processes, Multilayer Perceptrons, and Support Vector Machines
- Language:
- English
- Description:
- In this paper we present a comparison between the performance of Multilayer Perceptrons (MLPs) and Support Vector Machines (SVMs) in a problem of wind speed prediction. Specifically, we analyze the behavior of both algorithms within a larger system of wind speed prediction, formed by global and mesoscale weather forecasting models, and with a final statistical down-scaling process where the MLPs and the SVM are used. The final objective is to forecast the mean hourly wind speed prediction at wind turbines in a wind farm. This is an important parameter used to predict the total power production of the wind farm. The specific model for the short-term wind speed forecast we use integrates two different meteorological prediction global models, observations at the surface level and in different heights using atmospheric soundings. Also, it includes a mesoscale prediction model producing the inputs used in the MLP or the SVM, which will forecast the final wind speed at each turbine of the wind farm. In the experiments carried out we compare the results obtained using the MLP or SVM as final steps of the prediction system. Interesting differences of performance can be found when using MLPs or SVMs, which we analyze in this paper. The results obtained are encouraging anyway, and good short-term predictions of wind speed at specific points are obtained with both techniques.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
28907. Performance comparison of six efficient pure heuristics for scheduling meta-tasks on heterogeneous distributed environments
- Creator:
- Izakian , Hesam, Abraham, Ajith, and Snášel, Václav
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Heterogeneous distributed enviroments, scheduling, makespan, flowtime, and pure heuristic
- Language:
- English
- Description:
- Scheduling is one of the core steps to efficiently exploit the capabilities of heterogeneous distributed computing systems and represents an NP-complete problem. Therefore, using meta-heuristic algorithms is a suitable approach in order to cope with its difficulty. In many meta-heuristic algorithms, generating individuals in the initial step has an important effect on the convergence behavior of the algorithm and final solutions. Using some pure heuristics for generating one or more near-optimal individuals in the initial step can improve the final solutions obtained by meta-heuristic algorithms. Pure heuristics may be used solitary for generating schedules in many real-world situations in which using the meta-heuristic methods are too difficult or inappropriate. Different criteria can be used for evaluating the efficiency of scheduling algorithms, the most important of which are makespan and flowtime. In this paper, we propose an efficient pure heuristic method and then we compare the performance with five popular heuristics for minimizing makespan and flowtime in heterogeneous distributed computing systems. We investigate the effect of these pure heuristics for initializing simulated annealing meta-heuristic approach for scheduling tasks on heterogeneous environments.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
28908. Performance of a predatory ladybird beetle, Anegleis cardoni (Coleoptera: Coccinellidae) on three aphid species
- Creator:
- Kumar, Gyanendra and Sahu, Jyotsna
- Type:
- article, model:article, and TEXT
- Subject:
- Coccinellidae, Anegleis cardoni, prey, Aphis gossypii, Aphis craccivora, Lipaphis erysimi, reproduction, life table, and fitness
- Language:
- English
- Description:
- Qualitative and quantitative differences in prey are known to affect the life histories of predators. A laboratory study was used to evaluate the suitability of three aphid prey, Aphis gossypii, Aphis craccivora and Lipaphis erysimi, for the ladybird beetle, Anegleis cardoni (Weise). Development was fastest on A. gossypii followed by A. craccivora and L. erysimi. Percentage pupation, immature survival, adult weight and the growth index were all highest when reared on A. gossypii and lowest on L. erysimi. Similarly, oviposition period, lifetime fecundity and egg viability were all highest on a diet of A. gossypii, lowest on L. erysimi and intermediate on A. craccivora. Age-specific fecundity functions were parabolic. Adult longevity, reproductive rate and intrinsic rate of increase were all highest on A. gossypii and lowest on L. erysimi. Life table parameters reflected the good performance on A. gossypii and poor performance on L. erysimi. Estimates of individual fitness values for the adults reared on A. gossypii and A. craccivora were similar and higher than that of adults reared on L. erysimi. Thus, the three species of aphid can all be considered essential prey for A. cardoni.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
28909. Performance of classifcation confdence measures in dynamic classifer systems
- Creator:
- Štefka, David and Holeňa, Martin
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- classifier combining, dynamic classifier systems, and classification confidence
- Language:
- English
- Description:
- Classifier combining is a popular technique for improving classification quality. Common methods for classifier combining can be further improved by using dynamic classification confidence measures which adapt to the currently classified pattern. However, in the case of dynamic classifier systems, the classification confidence measures need to be studied in a broader context as we show in this paper, the degree of consensus of the whole classifier team plays a key role in the process. We discuss the properties which should hold for a good confidence measure, and we define two methods for predicting the feasibility of a given classification confidence measure to a given classifier team and given data. Experimental results on 6 artificial and 20 real-world benchmark datasets show that for both methods, there is a statistically significant correlation between the feasibility of the measure, and the actual improvement in classification accuracy of the whole classifier system; therefore, both feasibility measures can be used in practical applications to choose an optimal classification confidence measure.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
28910. Performance of homebalance test in an assessment of standing balance in elderly adults
- Creator:
- Kajzar, Jiří, Janatová, Markéta, Hill, Martin, Otáhal, Jakub, Nechlebová, Eva, Tichý, Miroslav, and Krejčí, Milada
- Format:
- počítač and online zdroj
- Type:
- model:article and TEXT
- Subject:
- homebalance test, elderly adults, standing balance, Tinetti Balance Assessment Tool, BMI, and fall risk prevention
- Language:
- English
- Description:
- Balance control is a critical task of daily life, the ability to maintain upright posture becomes of particular concern during aging when the sensory and motor system becomes deteriorated. Falls contribute to the most deaths caused by injury within the aged population, and the mortality rate following a fall is drastically elevated. Longitudinal and reliable assessment of balance control abilities is a critical point in the prediction of increased risk of falling in an elderly population. The primary aim of the study was to evaluate the efficiency of the Homebalance test in the identification of persons being at higher risk of falling. 135 subjects (82 women and 53 men) with geriatric syndrome have been recruited and the Homebalance and the Tinetti Balance test were performed. Results of both tests strongly correlated proving the good performance of the Homebalance test. Standing balance declines with increasing body mass index in both genders. Analysis of fluctuations of the center of pressure (COP) revealed higher frequency and magnitude in mediolateral direction COP movements when compared women to men. A strong negative correlation has been found between Tinetti static balance score and the total length of the COP trajectory during the examination on Homebalance (r = -0.6, p<0.001). Although both methods revealed good performance in detecting balance impairment, Homebalance test possesses higher precision due to the continuous nature of COP-derived parameters. In conclusion, our data proved that the Homebalance test is capable to identify persons with impaired balance control and thus are at higher risk of falling.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public