Numerical solution of linear time delay systems using Chebyshev-tau spectral method

In this paper, a hybrid method based on method of steps and a Chebyshev-tau spectral method for solving linear time delay systems of differential equations is proposed. The method first converts the time delay system to a system of ordinary dierential equations by the method of steps and then employs Chebyshev polynomials to construct an approx- imate solution for the system. In fact, the solution of the system is expanded in terms of orthogonal Chebyshev polynomials which reduces the solution of the system to the solution of a system of algebraic equations. Also, we transform the coefficient matrix of the algebraic system to a block quasi upper triangular matrix and the latter system can be solved more efficiently than the first one. Furthermore, using orthogonal Chebyshev polynomials enables us to apply fast Fourier transform for calculating matrix-vector multiplications which makes the proposed method to be more efficient. Consistency, stability and convergence analysis of the method are provided. Numerous numerical examples are given to demonstrate efficiency and accuracy of the method. Comparisons are made with available literature

Potential Seed Yield of Sterile F1 and 3-Way Crosses on Forage Sorghum-Sudan Hybrid in Egypt

Male-sterile F1\u27s from A x B line crosses and inbred A-lines of sorghum (Sorghum bicolar (L.) Moench) were investigated in relation to commercial production of hybrid seeds. Eight cytoplasmic male-sterile (CMS) A-lines, maintainer B-lines and the fertility restoring (R) sudangrass cultivar Greenleaf were selected to produce the hybrids evaluated in this study. Estimates of the parameters that describe seed yield and its components indicated that there were no general advantages for using sterile single crosses (SSC) over their prenatal (A) lines as the seed parent. As a group, the three-way hybrids and sterile single cross two way hybrids were not significantly different for any trait. However, some particular crosses showed significant positive heterosis for seed yield and its components, suggesting that dominant and epistatic gene actions were the cause of their superior performance. Therefore, the extra expense encountered in producing seed of a three-way sorghumsudangrass hybrid could be compensated for by using the superior crosses identified in this study

Učinak ketoprofena na koncentraciju u plazmi i farmakokinetičke pokazatelje ciprofloksacina u pilića

Ciprofloxacin (CFX) and ketoprofen (KPN) are used widely in combination in veterinary interventions for bacterial infections, so in this study the effect of KPN was studied on the efficacy of CFX, by measuring its plasma concentration and pharmacokinetic parameters in 7-10 day-old chickens. The analgesic median effective dose (ED50) of KPN was determined to be 1.62 mg/kg, IM, in the chickens. The preferable analgesic dose of KPN to be used with CFX was 4 mg/kg, IM, which differs significantly from KPN 2 mg/kg, IM,. The CFX plasma concentrations alone (8 mg/kg, IM) measured at different times (0.5, 1, 2, 4 and 24 hours) were 3.31, 3.60, 3.21, 2.70 and 0.17 μg/mL while its concentration was elevated by 53, 54, 90, 107 and 418 % when coadministered with KPN (4 mg/kg, IM) to 5.05, 5.53, 6.10, 5.59 and 0.88 μg/mL in the chickens, respectively. CFX pharmacokinetic parameters, such as the area under the curve (AUC), the area under the moment curve (AUMC), mean residence time (MRT), half-life (t1/2β), Tmax, and Cmax increased when KPN was coadministered with CFX by 129, 289, 70, 49, 100 and 69 %, whereas the elimination rate constant (Kel), the volume of distribution at steady state (Vss) and clearance (Cl) decreased by 36, 34 and 58 %, respectively. It was concluded that coadministration of KPN alters the plasma concentration and the pharmacokinetic parameters of CFX, suggesting that the CFX dose can be reduced when used with KPN to achieve the desired concentration of CFX in the plasma, as an antibacterial for treatment of infected animals.Kombinacija ciprofloksacina (CFX) i ketoprofena (KPN) u širokoj je upotrebi u veterinarskom liječenju bakterijskih infekcija. Ovo je istraživanje provedeno kako bi se ustanovio utjecaj KPN-a na učinkovitost CFX-a mjerenjem njegove koncentracije u plazmi i farmakokinetičkih pokazatelja u pilića starih između 7 i 10 dana. Procijenjeno je da je prosječna doza analgetičke učinkovitosti (ED50) KPN-a u pilića 1,62 mg/kg, intramuskularno. Poželjna analgetička doza KPN-a bila je 4 mg/kg, intramuskularno, što se znakovito razlikuje od doze KPN-a od 2 mg/kg, intramuskularno,koja se daje s CFX-om. Koncentracije CFX-a u plazmi (8 mg/kg, im.) u različitim vremenima mjerenja (0, 5, 1, 2, 4 i 24 sata) bile su 3,31, 3,60, 3,21, 2,70 i 0,17 μg/mL, a primijenjene zajedno s KPN-om (4 mg/kg, im) porasle su za 53, 54, 90, 107 i 418 % i iznosile 5,05, 5,53, 6,10, 5,59 i 0,88 μg/mL. Farmakokinetički pokazatelji CFX-a, koji uključuju područje ispod krivulje (AUC), područje ispod krivulje momenta (AUMC), prosječno vrijeme zadržavanja (MRT),poluživot (t1/2β), Tmax, i Cmax, porasli su kad je KPN primijenjen s CFX-om za 129, 289, 70, 49, 100 i 69 %, dok su se konstanta brzine eliminacije (Kel), volumen distribucije u stabilnom stanju (Vss) i klirens (Cl) smanjili za 36, 34 i 58 %. Zaključeno je da zajednička primjena KPN-a i CFX-a mijenja koncentraciju u plazmi i farmakokinetička svojstva CFX-a. Navedeno upućuje na to da bi se doza CFX-a mogla smanjiti kad se primjenjuje u kombinaciji s KPN-om, pri čemu se postigla željena koncentracija CFX-a u plazmi kao antibakterijskog lijeka za zaražene živoitnje

Website Phishing Detection Using Machine Learning Techniques

Phishing is a cybercrime that is constantly increasing in the recent years due to the increased use of the Internet and its applications. It is one of the most common types of social engineering that aims to disclose or steel users sensitive or personal information. In this paper, two main objectives are considered. The first is to identify the best classifier that can detect phishing among twenty-four different classifiers that represent six learning strategies. The second objective aims to identify the best feature selection method for websites phishing datasets. Using two datasets that are related to Phishing with different characteristics and considering eight evaluation metrics, the results revealed the superiority of RandomForest, FilteredClassifier, and J-48 classifiers in detecting phishing websites. Also, InfoGainAttributeEval method showed the best performance among the four considered feature selection methods

Marker hiding methods: Applications in augmented reality

© 2015 Taylor & Francis Group, LLC.In augmented reality, the markers are noticeable by their simple design of a rectangular image with black and white areas that disturb the reality of the overall view. As the markerless techniques are not usually robust enough, hiding the markers has a valuable usage, which many researchers have focused on. Categorizing the marker hiding methods is the main motivation of this study, which explains each of them in detail and discusses the advantages and shortcomings of each. The main ideas, enhancements, and future works of the well-known techniques are also comprehensively summarized and analyzed in depth. The main goal of this study is to provide researchers who are interested in markerless or hiding-marker methods an easier approach for choosing the method that is best suited to their aims. This work reviews the different methods that hide the augmented reality marker by using information from its surrounding area. These methods have considerable differences in their smooth continuation of the textures that hide the marker area as well as their performance to hide the augmented reality marker in real time. It is also hoped that our analysis helps researchers find solutions to the drawbacks of each method. © 201

Performance of a Nano PbS/Si Hetrojunction Deposited by chemical spray pyrolysis

ABSTRACT: Deposition of polycrystalline Lead sulfide nano thin films onto Si and glass substrates at temperatures (200-300 °C) was carried out by chemical spraying route using optimized preparative conditions. The XRD pattern confirmed the formation of PbS semiconducting films with orthorhombic structure. The electrical and optical properties of the nano crystalline thin films were studied aiming to better understanding for the electrical and opto-electrical properties of a hetrojunction with p-type Si. It was found that, the average grain size of PbS in the films was between 4 nm and 7 nm. The band gap was also calculated from the absorption co-efficient curves and showed a blue shift due to the grain size of the nan o PbS in the films. The current-voltage (I-V) and photoresponse characteristics were obtained with different illumination intensities. The detector exhibits an evident wide-range spectral responsivity

An Improved UFLS Scheme based on Estimated Minimum Frequency and Power Deficit

In the event of a power system disturbance, it is important that the decision to implement under frequency load shedding is based on both the minimum frequency and the magnitude of the disturbance. In this paper, we propose the use of higher order polynomial curve fitting to estimate the minimum frequency. If the prediction shows that the minimum frequency threshold will be violated, the magnitude of the total disturbance is estimated using the swing equation. In addition, the minimum amount of load that must be shed to restore the frequency just above the minimum value can also be directly calculated. Simulations are carried out for the considered Taiwan power system and the results prove the efficiency of the proposed technique

Cancer and thrombosis: Managing the risks and approaches to thromboprophylaxis

Patients with cancer are at increased risk of venous thromboembolism (VTE) compared with patients without cancer. This results from both the prothrombotic effects of the cancer itself and iatrogenic factors, such as chemotherapy, radiotherapy, indwelling central venous devices and surgery, that further increase the risk of VTE. Although cancer-associated thrombosis remains an important cause of morbidity and mortality, it is often underdiagnosed and undertreated. However, evidence is accumulating to support the use of low-molecular-weight heparins (LMWHs) in the secondary prevention of VTE in patients with cancer. Not only have LMWHs been shown to be at least as effective as coumarin derivatives in this setting, but they have a lower incidence of complications, including bleeding, and are not associated with the practical problems of warfarin therapy. Furthermore, a growing number of studies indicate that LMWHs may improve survival among patients with cancer due to a possible antitumor effect. Current evidence suggests that LMWHs should increasingly be considered for the long-term management of VTE in patients with cancer