This paper presents development of a day ahead load forecasting (DALF) model for Turkish power system with an artificial neural network (ANN). Effects of special holidays including national and religious days, and hourly random load deviations observed in Turkish power system due to significant arc furnace loads are discussed. Performance of the ANN is investigated in the sense of both DALF performance - in terms of both daily mean absolute percentage error (MAPE) and hourly absolute percentage error (APE) - and hourly secondary reserves required to ensure supply/demand adequacy of the system. The most sensitive cities to DALF in terms of daily city temperature forecasts are ranked in order to reduce the input of the developed ANN and thereby to improve execution of the model. Candidate cities are determined based on both their placement with respect to climatic zones of the country and their contribution to the system load during peak hours. The results show that, although a well-trained ANN could provide very satisfactory daily MAPEs at non-special days, such as ~1%, the hourly absolute percentage errors (APE) could be significant due to large random load disturbances, which necessitate special attention during the day ahead allocation of hourly secondary reserves. By limiting the temperature data set with major cities, the input of ANN reduces significantly while not disturbing the MAPEs. Main contributions of the study are; addressing both benefits of the prioritizing the cities in a power system in the sense of their temperature forecast effects on the DALF performance and assessing the performance of DALF in the sense of necessary amount of secondary reserves in power systems which include significant random load deviations (e.g., large arc furnace loads).
This paper describes the airliner wing flutter sensitivity analysis. The sensitivity coefficients define the influence of the structural parameter changes to tthe structure eigenvalue and flutter stability characteristics. Evaluated structural parameters represent the possible changes of the structure due to the installation of the smart high-lift devices at the leading and trailing edge region. In general, we can suppose the increasing of the mass and mass moment of inertia around the elastic axis and decreasing of the stiffness. Described effects are ordinarily considered destabilizing regarding the flutter. The main aim of the presented work is to evaluate the impact of components to the stability and to define the most critical regions or parameters. and Obsahuje seznam literatury
In laboratory experiments, conspecific excretions and ammonia solutions evoked avoidance reactions in tadpoles of three anuran species, Bufo bufo, Rana temporaria, and Rana arvalis . A differential sensitivity of ammonia chemoreception was determined for two anuran species. For Bufo bufo tadpoles, these characteristics at ammonia backgr ound concentration of 0.2 mg/l lied in the range 150 % < dI/I < 500 %, and for background of 0.4 mg/l the value lied in th e range 400 % < dI/I < 500 %. For Rana temporaria tadpoles, differential threshold against ammonia background concentration of 0. 15 mg/l was close to 200 % and against background ammonia concentration of 1.1 mg/l was close to 100 %. These results suggest that such sensitivity of both anurans is sufficient for using ammonia in intra- and interspecies communication., Y. B. Manteifel, E. I. Kiseleva., and Obsahuje bibliografii a bibliografické odkazy
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.
Abnormal accumulation of lymphoblasts in the blood and bone marrow is the main characteristic of acute lymphoblastic leukaemia (ALL). Glucocorticoids are effective drugs for ALL, while glucocorticoid resistance is an obstacle to ALL therapy. MicroRNAs (miRNAs) are implicated in the drug resistance and modulate the response of ALL to glucocorticoids. The role of miR-503 in glucocorticoid sensitivity of ALL was investigated in this study. Firstly, T-leukaemic cells were isolated from patients with ALL. The human ALL cell line (CCRF/CEM) was incubated with dexamethasone to establish a glucocorticoid- resistant ALL cell line (CCRF/CEM-R). Data from MTT showed that IC50 (50% inhibitory concentration) of dexamethasone in T-leukaemic cells isolated from glucocorticoid-resistant ALL patients or CCRF/CEM-R was increased compared with IC50 in T-leukaemic cells isolated from glucocorticoid- sensitive ALL patients or CCRF/CEM. MiR- 503 was down-regulated in glucocorticoid-resistant leukaemic cells and CCRF/CEM-R. Secondly, overexpression of miR-503 sensitized CCRF/CEM-R to dexamethasone. Moreover, over-expression of miR- 503 also promoted the sensitivity of ALL cells to dexamethasone. Thirdly, miR-503 bound to WNT3A mRNA and negatively regulated the expression of WNT3A. Over-expression of miR-503 reduced protein expression of nuclear β-catenin, and over-expression of WNT3A attenuated the miR-503 overexpression- induced decrease in nuclear β-catenin. Lastly, the over-expression of miR-503-induced increased sensitivity of ALL-resistant cells and CCRF/ CEM-R to dexamethasone was attenuated by overexpression of WNT3A. In conclusion, miR-503 targeted WNT3A mRNA to sensitize ALL cells to glucocorticoids through inactivation of the Wnt/β-catenin pathway.
The present study evaluates the performance of OptiMAL-IT® test and nested PCR assay in detection of malaria parasites. A total of 76 randomly selected blood samples collected from two malaria endemic areas were tested for malaria parasites using microscopy and OptiMAL-IT® test in the field. PCR assays were performed in the laboratory using DNA extracted from blood spots of the same samples collected on the FTA™ classic cards. Of the total of 61 field confirmed malaria positive samples, only 58 (95%) were detected positive using microscopy in the laboratory. Sensitivity, specificity, positive predictive value, negative predictive value and false discovery rate of OptiMal-IT® in comparison to the microscopy were 93%, 83%, 95%, 79% and 5%, respectively. On the other hand, the sensitivity and specificity of PCR assay were 97% and 100 %, respectively, whereas positive predictive value, negative predictive value and false discovery rate were 100%, 90% and 0%, respectively. The overall performance of OptiMal-IT® and PCR assays for malaria diagnosis was 76% and 97%, respectively. PCR assay enabled the identification of infection with Plasmodium malariae Laveran, 1881 in four samples misidentified by microscopy and Plasmodium-specific antigen (PAN) identified by the OptiMAL-IT® test. In addition to the standard methods, such PCR assay could be useful to obtain the real incidence of each malaria parasite species for epidemiological perspectives.
Olfaction enables most mammalian species to detect and discriminate vast numbers of chemical structures called odorants and pheromones. The perception of such chemical compounds is mediated via two major olfactory systems, the main olfactory system and the vomeronasal system, as well as minor systems, such as the septal organ and the Grueneberg ganglion. Distinct differences exist not only among species but also among individuals in terms of their olfactory sensitivity; however, little is known about the mechanisms that determine these differences. In research on the olfactory sensitivity of mammals, scientists thus depend in most cases on behavioral testing. In this article, we reviewed scientific studies performed on various mammalian species using different methodologies and target chemical substances. Human and non-human primates as well as rodents and dogs are the most frequently studied species. Olfactory threshold studies on other species do not exist with the exception of domestic pigs. Olfactory testing performed on seals, elephants, and bats focused more on discriminative abilities than on sensitivity. An overview of olfactory sensitivity studies as well as olfactory detection ability in most studied mammalian species is presented here, focusing on comparable olfactory detection thresholds. The basics of olfactory perception and olfactory sensitivity factors are also described., M. Wackermannová, L. Pinc, L. Jebavý., and Obsahuje bibliografii
Transportation system safety and reliability pertain to the dominant factors affecting present life of human society. In this paper, we describe the method for an analysis and further subsequent optimization of complex transportation system safety and reliability based on their complex sensitivity investigation. Reasonable applications of this theoretical tool can also be used for improvement of complex transportation system resistance against terrorist activities.
The aim of this article is to provide an overview of the problems associated with the fielding of questions of a socially sensitive nature typically dealing with crime, health, and sexual activity in nationally representative sample surveys. This article presents an overview of previous research on this topic and associated themes such as the definition of sensitive survey questions, the emergence and impact of social desirability effects and application of the Cognitive Aspects of Survey Methodology (CASM) to mechanisms of question response on sensitive topics. Thereafter, this article maps out specific sources of error that are likely to occur when fielding sensitive survey questions; and highlights methods that may used to minimise measurement error, thereby enhancing data validity. The article concludes with an appraisal of some of the most influential criterion-validity used in this sub-field of survey research., Johana Chylíková., and Obsahuje bibliografii a bibliografické odkazy
The aim of this article is to provide an overview of the problems associated with the fielding of questions of a socially sensitive nature typically dealing with crime, health, and sexual activity in nationally representative sample surveys. This article presents an overview of previous research on this topic and associated themes such as the definition of sensitive survey questions, the emergence and impact of social desirability effects and application of the Cognitive Aspects of Survey Methodology (CASM) to mechanisms of question response on sensitive topics. Thereafter, this article maps out specific sources of error that are likely to occur when fielding sensitive survey questions; and highlights methods that may used to minimise measurement error, thereby enhancing data validity. The article concludes with an appraisal of some of the most influential criterion-validity used in this sub-field of survey research.