Real-time power system security assessment

The increasing complexity of modern power systems has led to a greater dependence on automatic control at all levels of operation. Large scale systems of which a power system is a prime example, is an area in which a wide gap exists between theoretical mathematically based research and engineering practice. The research programme at Durham is directed towards bridging this gap by linking some of the available and new theoretical techniques with the practical requirements of on-line computer control in power systems. This thesis is concerned with the assessment of security of power systems in real-time operation. The main objective of this work was to develop a package to be incorporated in the University of Durham On line Control of Electrical Power Systems (OCEPS) suite to cater for network islanding and analyse the features and the feasibility of a real-time 'security package’ for modern energy control centres. The real-time power systems simulator developed at Durham was used to test the algorithms and numerical results obtained are presented

Genetic and phenotypic parameters of body temperature and respiration rate in fayoumi chicks

International audienc

Double Relaxation via AdS/CFT

We exploit the AdS/CFT correspondence to investigate thermalization in an N=2 strongly coupled gauge theory including massless fundamental matter (quark). More precisely, we consider the response of a zero temperature state of the gauge theory under variation of an external electric field leading to a time-dependent current. The holographic dual of the above set-up is given by introducing a time-dependent electric field on the probe D7-brane embedded in an AdS_5 X S^5 background. In the dual gravity theory, due to a time-dependent electric field an apparent horizon forms on the brane which, according to AdS/CFT dictionary, is the counterpart of the thermalization process in the gauge theory. We classify different functions for time-dependent electric field and study their effect on the apparent horizon formation. In the case of pulse functions where the electric field varies from zero to zero, apart from non-equilibrium phase, we observe that two apparent horizons form on the brane. On the gauge theory side, it means that the state of the gauge theory experiences two different temperatures during the time evolution.Comment: 28 pages, 13 figures, published versio

PHARMACISTS' PERCEPTION OF THEIR ROLE AND ASSESSMENT OF CLINICAL PHARMACY EDUCATION TO IMPROVE CLINICAL PHARMACY SERVICES IN INDONESIAN HOSPITALS

Objectives: To identify the pharmacists' perception on their role, barriers to implement clinical pharmacy services (CPSs), and importance of clinical pharmacy education (CPE) to improve CPSs in Indonesian hospitals. Methods: A predetermined questionnaire was distributed to pharmacists (n=49) in Haji Adam Malik, Pirngadi, Haji, and Columbia Hospitals and staffs of Faculty of Pharmacy, University of Sumatera Utara, Indonesia for the two-month period in 2012. The participants were asked to choose answering yes or no for the importance of CPSs, poor to excellent for the current CPSs, not agree to strongly agree for the usefulness and target of CPE, way and whom to deliver it, rank priority-based topic of CPE, and choose the appropriate size, frequency, and duration of the CPE. The participants' responses were analyzed using Statistical Package for the Social Sciences (SPSS, version 19, Chicago, IL, USA). Results: Mean age of the participants was 48.38 ± 10.66 (years) with working experience of 17.50±9.06 (years). Most of them (82%) were female. The majority of them (79.2%) graduated pharmacy degree. Pharmacists (44.9%) argued that their understanding on clinical pharmacy (CP) was still fair. Nearly half of the participants (44.9%) revealed that CPSs in these hospitals were poor. Most of them declared that CPE was important to improve their knowledge and healthcare. Conclusions: This study confirms that knowledge of pharmacists on CP as well as CPSs in Indonesian hospitals still need improvement through CPE to optimize health services

Effects of arbitrary shear stress on unsteady free convection flow of Casson fluid past a vertical plate

This article studies the unsteady free flow of a Casson fluid over an infinite vertical plate with constant wall temperature. The Problem is modelled by employing equations of continuity, momentum and energy. Exact solutions for the dimensionless velocity and temperature are established by the Laplace transform technique. The solutions that have been obtained, uncommon in the literature, satisfy all imposed initial and boundary conditions and can generate huge number of solutions for any motion problem with technical relevance of this type. For illustration, some special cases are considered. The velocity solutions are presented as a sum of convective and mechanical parts. Pertinent results are discussed and displayed graphically

Effect of Resin Coating and Chlorhexidine on Microleakage of Two Resin Cements after Storage

Objective: Evaluating the effect of resin coating and chlorhexidine on microleakage of two resin cements after water storage.Materials and Methods: Standardized class V cavities were prepared on facial and lingual surfaces of one hundred twenty intact human molars with gingival margins placed 1mm below the cemento-enamel junction. Indirect composite inlays were fabricated and thespecimens were randomly assigned into 6 groups. In Groups 1 to 4, inlays were cemented with Panavia F2.0 cement. G1: according to the manufacturer’s instruction. G2: with light cured resin on the ED primer. G3: chlorhexidine application before priming. G4: withchlorhexidine application before priming and light cured resin on primer. G5: inlays were cemented with Nexus 2 resin cement. G6: chlorhexidine application after etching. Each group was divided into two subgroups based on the 24-hour and 6-month water storagetime. After preparation for microleakage test, the teeth were sectioned and evaluated at both margins under a 20×stereomicroscope. Dye penetration was scored using 0-3 criteria.The data was analyzed using Kruskal-Wallis and complementary Dunn tests.Results: There was significantly less leakage in G2 and G4 than the Panavia F2.0 control group at gingival margins after 6 months (P<0.05). There was no significant differences in leakage between G1 and G3 at both margins after 24 hours and 6 months storage. After 6months, G6 revealed significantly less leakage than G5 at gingival margins (P=0.033). In general, gingival margins showed more leakage than occlusal margins.Conclusion: Additionally, resin coating in self-etch (Panavia F2.0) and chlorhexidine application in etch-rinse (Nexus) resin cement reduced microleakage at gingival margins after storage

Caesarean Risk Factors in Northern Region of Bangladesh: A Statistical Analysis

Purpose: To explore the measurement of a scale of caesarean (C-section) risk factors and degree of risk contribution in different health facilities and to determine a suitable graphical representation (image) of caesarean cases.Methods: Based on seventeen indicators, a composite index was computed for each respondent and classified into three groups using Beta distribution of first kind. For the analysis of contribution of risk factors between private and public patients, principal component analysis (PCA) was also used. An attempt was made to visualise a suitable graphical representation of caesarean cases by independent component analysis (ICA).Results: The selected risk factors were more contributory to public hospital patients than to those in private hospitals on the basis of higher estimated value of range (R = 0.134) but a higher proportion of C-section occurred in private (93.4 %) than in public hospitals (30.3 %). On the other hand, PCAshowed that the contribution of selected risk factors accounts for approximately 60.0 % and 68.5 % in private and public hospitals, respectively. Furthermore, from the various graphical representation, thenumbers of private patients were more interlinked by ICA but not of the other graphical representations of PCA.Conclusion: We had expected the rate of C-section would be higher among public hospital patients than private hospital patients but the results obtained indicate the reverse. It seems that the combination of the propensity of private practice doctors to carry out C-section and the financial benefits on the part of private hospitals may be contributory factors to the caesarean section rates in private health facilities.Keywords: Caesarean risk factors, Composite index, Principal component analysis (PCA), Independent component analysis (ICA)

Retina fundus image mask generation using pseudo parametric modeling technique

ABSTRACT (abstract): The use of vascular intersection as one of the symptoms for monitoring and diagnosis of diabetic retinopathy from Fundus images have been widely reported in literatures. In this work, a new hybrid approach that makes use of three different methods of vascular intersection detection namely Modified Cross-Point Number (MCN), Combine Cross-Points Number (CCN) and Artificial Neural Network (ANN) technique is hereby proposed. Result obtained from the application of this technique to both simulated and experimental shows a very high accuracy and precision value in detecting both bifurcation and cross over points. Thus an improvement in bifurcation and vascular point detection and a good tool in the monitoring and diagnosis of diabetic retinopath