Smart windows: Thermal modelling and evaluation

Copyright @ 2014 The Authors. Published by Elsevier Ltd. This is an open access article shared under the CC BY license (http://creativecommons.org/licenses/by/3.0/).A numerical investigation of the performance of a multi paned smart window integrated with water-cooled high efficiency third generation GaAsP/InGaAs QWSC (∼32% efficiency) solar cells illuminated by two-axis tracking solar concentrators at 500× in the inter pane space is presented. Optimising system parameters such as optical concentration ratio and coolant (water) flow rate is essential in order to avoid degradation in system performance due to high cell temperatures and thermal stresses. Detailed modelling of the thermo-fluid characteristics of the smart windows system was undertaken using a finite volume CFD package. Results of this analysis which considered the conductive, convective and radiative heat exchange processes taking place in the interior of the smart window system as well as the heat exchange to the internal and external ambient environment are presented.Engineering and Physical Sciences Research Counci

Towards a Proactive Role of Internal Auditors in Anti-Money Laundry Compliance Review: An Egyptian Perspective

The banking sector is crucial to any financial sector's stability and prosperous. But Money laundering (ML) threatens such stability through its vicious consequences. Thus, the need for a solid and rigorous AML programs emerged. In the light of the drastic evolution of the business environment over the last decades to rely heavily on information technology (IT), The new role for internal auditors (IAs) needed to convoy such evolution by advancing from traditional and reactive role to a more proactive and strategic role. No study has closely investigated the impact of IAs involvement in IT governance on IAs effectiveness in AML compliance review. A survey was developed based on the prior literature and was administered IAs in the Egyptian Banking sector. In all, 39 usable questionnaires were received. Smart partial least square was used to analyse the responses, the results indicated that IAs involvement in IT governance structures and relational capabilities significantly affected the IAs effectiveness. But IT involvement in processes was found to be insignificant. The overall results should be useful to banks in general, seeking to utilize the IAs to the full their aptitude in combating ML through improving the IAs effectiveness in AML compliance review. Keywords: IT governance, AML compliance review, Internal Auditor

Genetic Algorithm Based Control System Design of a Self-Excited Induction Generator

This paper presents an application of the genetic algorithm (GA) for optimizing controller gains of the Self-Excited Induction Generator (SEIG) driven by the Wind Energy Conversion Scheme (WECS). The proposed genetic algorithm is introduced to adapt the integral gains of the conventional controllers of the active and reactive control loop of the system under study, where GA calculates the optimum value for the gains of the variables based on the best dynamic performance and a domain search of the integral gains. The proposed genetic algorithm is used to regulate the terminal voltage or reactive power control, by adjusting the self excitation, and to control the mechanical input power or active power control by adapting the blade angle of WECS, in order to adjust the stator frequency. The GA is used for optimizing these gains, for an active and reactive power loop, by solving the related optimization problem. The simulation results show a better dynamic performance using the GA than using the conventional PI controller for active and reactive control

Statistical exponential distribution function as distance indicator to stellar groups

AbstractIn this paper, statistical distribution functions are developed for distance determination of stellar groups. This method depends on the assumption that, absolute magnitudes and apparent magnitudes follow an exponential distribution function. The developed approaches have been implemented to determine distances of some clusters and stellar associations. The comparison with the distances derived by different authors revealed good agreement

Geometry of Discrete Quantum Computing

Conventional quantum computing entails a geometry based on the description of an n-qubit state using 2^{n} infinite precision complex numbers denoting a vector in a Hilbert space. Such numbers are in general uncomputable using any real-world resources, and, if we have the idea of physical law as some kind of computational algorithm of the universe, we would be compelled to alter our descriptions of physics to be consistent with computable numbers. Our purpose here is to examine the geometric implications of using finite fields Fp and finite complexified fields Fp^2 (based on primes p congruent to 3 mod{4}) as the basis for computations in a theory of discrete quantum computing, which would therefore become a computable theory. Because the states of a discrete n-qubit system are in principle enumerable, we are able to determine the proportions of entangled and unentangled states. In particular, we extend the Hopf fibration that defines the irreducible state space of conventional continuous n-qubit theories (which is the complex projective space CP{2^{n}-1}) to an analogous discrete geometry in which the Hopf circle for any n is found to be a discrete set of p+1 points. The tally of unit-length n-qubit states is given, and reduced via the generalized Hopf fibration to DCP{2^{n}-1}, the discrete analog of the complex projective space, which has p^{2^{n}-1} (p-1)\prod_{k=1}^{n-1} (p^{2^{k}}+1) irreducible states. Using a measure of entanglement, the purity, we explore the entanglement features of discrete quantum states and find that the n-qubit states based on the complexified field Fp^2 have p^{n} (p-1)^{n} unentangled states (the product of the tally for a single qubit) with purity 1, and they have p^{n+1}(p-1)(p+1)^{n-1} maximally entangled states with purity zero.Comment: 24 page

Transmission lines modelling based on RLC passive and active filter design

This paper presents a transmission line (TL) modelling which is based upon vector fitting algorithm and RLC passive filter design. Frequency Response Analysis (FRA) is utilised for behaviour prediction and fault diagnosis. The utilities of the measured FRA data points need to be enhanced with suitable modelling category to facilitate the modelling and analysis process. This research proposes a new method for modelling the transmission line based on a rational approximation function which can be extracted through the Vector Fitting (VF) method, based on the frequency response measured data points. A set of steps needs to be implemented to achieve this by setting up an extracted partial fraction approximation, which results from a least square RMS error via VF. Active and passive filter design circuits are used to construct the model of the Transmission line. The RLC design representation was implemented for modelling the system physically while MATLAB Simulink was used to verify the results

GASTRORETENTIVE NIZATIDINE LOADING MICROBALLOONS FOR TREATMENT OF PEPTIC ULCER

Objective: The aim of the present work was to formulate a controlled release dosage form of water soluble drug such as Nizatidine to increase its gastric retention in the stomach and consequently, enhance its absorption and improve its bioavailability.Methods: Microballoons were prepared by emulsion non solvent evaporation method using ethyl cellulose 7 CP in different ratios. The prepared microballoons were evaluated for yield percentage, entrapment efficiency, in vitro buoyancy and in vitro dissolution.Results: Results showed that as drug to polymer ratio increased from 1:1 to 1:5 yield percentage, entrapment efficiency, in vitro buoyancy increased from 70.4+1.5 to87.2+1.8, from 71.5+2.1 to 90.2+2.6 and from 82.1+3.2 to 93.2+2.6, respectively, while the amount of drug released decreased from 88.1+2.1 to 68.9+1.8. When stirring rate increased from 800 rpm to 1600 rpm, the three parameters decreased from 93.2+2.7 to 81.5, from 96.4+3.5 to 82.6+1.7 and from 97+5.4 to 88.2+4.1, respectively, while the amount released increased from 63.1+2.6 to 73.8+1.2. When Span 80 concentrations increased from 0.1% to 2% the three parameters decreased from 95.2+2.6, to 81.6+3.2, from 97.6+1.8 to 82.4+1.8 and from 97.3+5.2 to 89.1+4.6, respectively, and the amount released percentage increased from 61.2+2.6 to 76.1+1.6. All drug release showed Higuchi diffusion models. The increase in the mean Tmax and the decrease in the mean Cmax of microballoons compared to the plain drug indicate a sustained release of microballoons and reflects a high improvement in its bioavailability.Conclusion: It is evident from this study that microballoons are promising gastric prolonging the delivery system for nizatidine and have good stability.Â

Modulational instability of ion-acoustic wave packets in quantum pair-ion plasmas

Amplitude modulation of quantum ion-acoustic waves (QIAWs) in a quantum electron-pair-ion plasma is studied. It is shown that the quantum coupling parameter $H$ (being the ratio of the plasmonic energy density to the Fermi energy) is ultimate responsible for the modulational stability of QIAW packets, without which the wave becomes modulational unstable. New regimes for the modulational stability (MS) and instability (MI) are obtained in terms of $H$ and the positive to negative ion density ratio $\beta$. The growth rate of MI is obtained, the maximum value of which increases with $\beta$ and decreases with $H$. The results could be important for understanding the origin of modulated QIAW packets in the environments of dense astrophysical objects, laboratory negative ion plasmas as well as for the next generation laser solid density plasma experiments.Comment: 4 pages, 2 figures (to appear in Astrophysics and Space Science

Effect of oxytocin infusion versus tranexamic acid on reducing blood loss during hysteroscopic myomectomy: a randomized controlled trial

Background: Women undergoing hysteroscopic myomectomy are prone to significant blood loss and hematological disturbances. Oxytocin is a uterotonic drug, used mainly in obstetric practice. Tranexamic acid is a haemostatic drug that has been used to reduce blood loss after trauma and in many surgeries. The aim of our study was to compare the safety and efficacy of oxytocin versus tranexamic acid in reducing perioperative blood loss during hysteroscopic myomectomy.Methods: This study included 60 patients scheduled for hysteroscopic myomectomy allocated into 2 groups: group A: received 10 mg/kg of tranexamic acid slowly intravenous after induction of anesthesia, while group B: received infusion of 10 IU of oxytocin at a rate of 400 mIU/min throughout the procedure. Preoperative and postoperative hemoglobin and hematocrit levels, need for blood transfusion, duration of operation, complications and medications adverse effects were recorded.Results: The 2 groups were comparable in terms of the mean difference between preoperative and postoperative hemoglobin a hematocrit levels, operative time, operative complication and medications’ adverse effects. No patients needed blood component transfusion in either group.Conclusions: It can be concluded that tranexamic acid and oxytocin are equally effective in reducing blood loss and transfusion requirements during hysteroscopic myomectomy with comparable good safety profiles. Both of them can be used according to availability and surgeon preferences