423 research outputs found

    The application of perception theory in architecture and urban design with particular reference to Liberation Square in Cairo.

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    Perception in architecture and the environment, which is the main concern of this thesis, can be counted as one part of the whole subject of perception. However, currently there is a great lack of application and utilisation of knowledge of that field. One can say that dissatisfaction with undesirable results in the design of our environment and with its design courses, were the main motive behind the researcher's venture into the field of perception and its application to both architecture and urban design. Within the general structure of the research are four case studies chosen as practical applications in these two subject areas, from the point of view of the field of perception. These cases respectively are: The Seventh Heaven Competition, Seventh Heaven 2, The Parliament Square Competition, and finally, the redesign of the Liberation Square in Cairo (Egypt). The redesign of Liberation Square (Maydan Al-Tahrir), in particular is treated as the principal case study through which the researcher attempts both to evaluate the role of the square as a symbolic urban space in Cairo and to redesign it within the methodology derived from his researches. It is worthy of note that the researcher uses the 'questionnaire' as a means of eliciting subjective responses, side by side with a theoretical analysis which mainly has a bias towards psychological and perceptual interpretation. The third part has only one chapter comprising two case studies of a project in Regent's Park in London, 1983. The fourth part has two chapters; these comprise a discussion of the theoretical background to that entity, the square in the city. It comprises a third case study for a project based on a competition for redesigning Parliament Square in London, 1984. The sixth part describes the methodology used in analysing the final case study, that of 'Liberation Square in Cairo'. The seventh part comprises the analysis of 'Liberation Square' in Cairo on two levels: (i) the square as an individual locus, the styles of its buildings, its function, symbolism and validity as a public urban space; and (ii) the square in terms of its relationship to the city as a component of its organism

    Removal of Cd2+ from aqueous solution by zeolite synthesized from Egyptian kaolin

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    Zeolite Na-Y was prepared from kaolin located in Wadi-Hagul, Suez, Egypt. The synthetic zeolite prepared by the hydrothermal reaction of kaolin was characterized by X-ray fluorescence (XRF), X-ray diffraction (XRD), scanning electron microscopy (SEM) and cation exchange capacity (CEC). Cadmium ion removal was investigated using the synthetic solution of Cd2+ ions with different concentrations at room temperature (25 °C ± 0.2), initial pH of the solution and contact times. The optimum contact time for removal of Cd2+ ion was 10 min, with 0.1g of synthetic zeolite and pH 7.57. The experimental data were correlated using Langmuir, Freundlich and Harkins-Jura adsorption isotherms. The maximum adsorption capacity Qm obtained from the Langmuir isotherm was 14.006 mg/g for Cd2+ ion. Kinetic studies reveal that synthetic zeolite is more effective as adsorbent for removing cadmium ion

    Robust Parameters Tuning of Different Power System Stabilizers Using a Quantum Artificial Gorilla Troops Optimizer

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    Electrical power system abnormalities may have several negative consequences on its stable operation. As a result, preserving its stability under such operational states has become an ongoing challenge for power engineers. PSSs are created as auxiliary controllers to address the instability issues produced upon disturbances. They dampen the oscillations induced by the disturbances by giving the system the necessary damping torque. This research aims at presenting a comprehensive study for the optimum tuning of power system stabilizer (PSS) of different structures. This aim is accomplished with the help of a novel modified optimization algorithm called Quantum Artificial Gorilla Troops Optimizer. The modified optimizer\u27s validation is first investigated with the well-known benchmark optimization functions and shows superiority over Gorilla Troops Optimizer and competitive algorithms. The research is extended to the application of the optimum tuning of various PSS structures of the single machine to the infinite bus model. The proposed optimization algorithm shows fast convergence over investigated optimization algorithms. Moreover, the Tilt-integral-derivative based PSS shows better performance characteristics in terms of lower settling time and lower maximum and undershoot values over the conventional lead-lag PSS, dual input PSS, and fractional-order proportional-integral-derivative based PSS

    An improved wild horse optimization algorithm for reliability based optimal DG planning of radial distribution networks

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    This paper introduces a novel technique for optimal distribution system (DS) planning with distributed generation (DG) systems. It is being done to see how active and reactive power injections affect the system’s voltage profile and energy losses. DG penetration in the power systems is one approach that has several advantages such as peak savings, loss lessening, voltage profile amelioration. It also intends to increase system reliability, stability, and security. The main goal of optimal distributed generation (ODG) is a guarantee to achieve the benefits mentioned previously to increase the overall system efficiency. For extremely vast and complicated systems, analytical approaches are not suitable and insufficient. Therefore, several meta-heuristic techniques are favored to obtain better performance from were convergence and accuracy for large systems. In this paper, an Improved Wild Horse Optimization algorithm (IWHO) is proposed as a novel metaheuristic method for solving optimization issues in electrical power systems. IWHO is devised with inspirations from the social life behavior of wild horses. The suggested method is based on the horse’s decency. To assess the efficacy of the IWHO, it is implemented on the 23 benchmark functions Reliability amelioration is the most things superb as a result of DGs incorporation. Thus, in this research, a customer-side reliability appraisal in the DS that having a DG unit was carried out by a Monte Carlo Simulation (MCS) approach to construct an artificial history for each ingredient across simulation duration. For load flow calculations, the backward Forward Sweep (BFS) technique has been employed as a simulation tool to assess the network performance considering the power handling restrictions. The proposed IWHO method has been measured on IEEE 33 69 and 119 buses to ascertain the network performing in the presence of the optimal DG and the potential benefits of the suggested technique for enhancing the tools used by operators and planners to maintain the system reliability and efficiency. The results proved that IWHO is an optimization method with lofty performance regarding the exploration–exploitation balance and convergence speed, as it successfully handles complicated problems

    EFFECT OF COMPOST, BIO AND NPK FERTILIZATION ON ESSENTIAL OIL PRODUCTION OF YARROW FLOWERING TOPS, ACHILLEA MILLEFOLIUM, L.

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    The effects of compost (5, 7.5 and 10 ton/fed), NPK (50, 75 and 100%) and/or Effective micro-organisms/Minia Azotein fertilization on plant height, number and dry weight of flowering tops/plant and essential oil productivity (% and yield/plant) were investigated during 2012/2013 and 2013/2014 at the experimental farm, Fac. of Agric., Minia Univ. All treatments of compost significantly increased, plant height, number and dry weight of flowering tops/plant, as well as, essential oil percent and yield/plant. The high level of compost was more effective in this concern. The used of mineral NPK (100%) followed by 75% NPK + E.M. + M.A. treatments were the best results in increasing all previous characters. Generally supplying yarrow plants with compost at the rate of 10 ton/fed and fertilizing plants with NPK (100%) or reduce dose at (75% NPK) plus E.M. + M.A. gave overall the highest values of previous traits

    Influence of immediate postpartum contraception counseling on the rate of unintended pregnancy in primigravida: a randomized controlled study

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    Background: The current study aims to assess the influence of immediate postpartum counselling about effective contraceptive methods to be used by primigravida on the rate of unintended pregnancy during first 6 months post-partum.Methods: The study was a prospective randomized controlled trial for assessment the influence of immediate postpartum counseling about effective contraceptive methods to be used by primigravida on the rate of unintended pregnancy during first 6 months post-partum who delivered at the period between the 1st of December 2016 and 31st of December 2017. The study patients were randomly assigned into two groups: Group (A) were received counseling about contraceptive methods using illustrations through postpartum interview with the study researcher. Group (B) were not received any counseling about contraceptive methods. The primary outcome was the difference in the rate of unintended pregnancy in both groups.Results: No significant difference between both groups in preventing unintended pregnancy. In group (A): After 3 months postpartum 140 women (93.3%) were used the contraceptive method correctly. 10 women used method incorrectly and 2 of them get pregnant. After 6 months postpartum 8 women did not use any method but 134 women (95.7%) were correctly used the contraceptive method. In group (B): After 3 months postpartum 127 women (84.7%) were used the contraceptive method correctly. 23 women used method incorrectly and 4 of them get pregnant. After 6 months postpartum 1 woman did not use any method but 30 women (20.7%) were incorrectly used the contraceptive method.Conclusions: Immediate post-partum counseling about contraceptive methods is good tool to educate women who intend to have optimal inter–pregnancy period about the effective methods that suit them and when to initiate

    Evaluation of adnexal masses by Three-Dimensional ultrasound multi-slice view: Do we really need it?

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    Objective:The purpose of this study is to evaluate the benefit of use of three-dimensional ultrasound multi-slice view in detailed assessment of adnexal masses morphology. Methods:Two-hundred thirty one patients with adnexal masses elected for surgery at Woman’s Health Center, Assiut, Egypt between October 2012 and October 2013 were recruited for the study. Each patient had 2D ultrasound and detailed morphological evaluation was reported. Then, 3D ultrasound volumes were obtained. The stored 3D volumes were then digitally analyzed using 3D ultrasound multi-slice view. The results of 2D, 3D ultrasound multi-slice were compared to the postoperative histopathological findings.Results:The mean age of included patients was 30.2 ± 12.7 years. Overall, 189 patients (81.8%) confirmed to have benign masses, and 42 patients (18.2%) with malignant masses according to their final histopathological analysis. Subjective assessment by 2D ultrasound correctly classified 95.6% of benign masses and 87% of malignant masses. On detailed assessment of the masses by 3D ultrasound multi-slice view, there was agreement in morphological assessment of all masses except in 3 cases in which 3D ultrasound multi-slice view permitted better description of their morphological criteria and hence changing the presumed diagnosis and management.Conclusions: The ability of detailed analysis of the volumes taken during 3D ultrasound using multi-slice view can aid in better morphological assessment of adnexal masses especially in detection of papillary projections in adnexal cysts. This information is valuable in deciding the optimal management of adnexal masses in some cases

    In vitro evaluation of electroporated gold nanoparticles and extremely-low frequency electromagnetic field anticancer activity against Hep-2 laryngeal cancer cells

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    Introduction. The extremely-low frequency electromagnetic field (ELFEMF) has been proposed for use in cancer therapy since it was found that magnetic waves interfere with many biological processes. Gold nanoparticles (Au-NPs) have been widely used for drug delivery during cancer in vitro studies due to their low cytotoxity and high biocompatibility. The electroporation of cancer cells in a presence of Au-NPs (EP Au-NPs) can induce cell apoptosis, alterations of cell cycle profile and morphological changes. The impact of ELFEMF and EP Au-NPs on morphology, cell cycle and activation of apoptosis-associated genes on Hep-2 laryngeal cancer cell line has not been studied yet. Materials and methods. ELFEMF on Hep-2 cells were carried out using four different conditions: 25/50 mT at 15/30 min, while Au-NPs were used as direct contact (DC) or with electroporation (EP, 10 pulses at 200V, equal time intervals of 4 sec). MTT assay was used to check the toxicity of DC Au-NPs. Expression of CASP3, P53, BAX and BCL2 genes was quantified using qPCR. Cell cycle was analyzed by flow cytometry. Hematoxylin and eosin (HE) staining was used to observe cell morphology. Results. Calculated IC50 of DC Au-NPs 24.36 μM (4.79 μg/ml) and such concentration was used for further DC and EP AuNPs experiments. The up-regulation of pro-apoptotic genes (CASP3, P53, BAX) and decreased expression of BCL2, respectively, was observed for all analyzed conditions with the highest differences for EP AuNPs and ELFEMF 50 mT/30 min in comparison to control cells. The highest content of cells arrested in G2/M phase was observed in ELFEMF-treated cells for 30 min both at 25 or 50 mT, while the cells treated with EP AuNPs or ELFEMF 50 mT/15 min showed highest ratios of apoptotic cells. HE staining of electroporated cells and cells exposed to ELFEMF’s low and higher frequencies for different times showed nuclear pleomorphic cells. Numerous apoptotic bodies were observed in the irregular cell membrane of neoplastic and necrotic cells with mixed euchromatin and heterochromatin. Conclusions. Our observations indicate that treatment of Hep-2 laryngeal cancer cells with ELFEMF for 30 min at 25–50 mT and EP Au-NPs can cause cell damage inducing apoptosis and cell cycle arrest

    An efficient electric charged particles optimization algorithm for numerical optimization and optimal estimation of photovoltaic models

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    The electric charged particles optimization (ECPO) technique is inspired by the interaction (exerted forces) between electrically charged particles. A developed version of ECPO called MECPO is suggested in this article to enhance the capability of searching and balancing the exploitation and exploration phases of the conventional ECPO. To let the search agent jumps out from the local optimum and avoid stagnation in the local optimum in the proposed MECPO, three different strategies in the interaction between ECPs are modified in conjunction with the conventional ECPO. Therefore, the convergence rate is enhanced and reaches rapidly to the optimal solution. To evaluate the effectiveness of the MECPO, it is executed on the test functions of the CEC’17. Furthermore, the MECPO technique is suggested to estimate the parameters of different photovoltaic models, such as the single-diode model (SDM), the double-diode model (DDM), and the triple-diode model (TDM). The simulation results illustrate the validation and effectiveness of MECPO in extracting parameters from photovoltaic models
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