556 research outputs found

    What is unpaid female labour worth? Evidence from the Time Use Studies of Iran in 2008 and 2009

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    This paper uses the Time Use Survey of Iran of 2008 and 2009 to estimate the monetary value of unpaid domestic work of urban housewives. The surveys recorded domestic work activities such as cooking and cleaning and general care of household members as well as care of children and their education. Using the market-based approach to estimate the monetary value of unpaid domestic work we collected data on the cost of buying in services for domestic work and for education of children from ‘nursing agencies’ and private education colleges in main cities of Iran in the summer of 2011 that were adjusted to obtain the 2008 and 2009 prices. The market value of domestic work of urban housewives was estimated to be US25billionin2008andUS25 billion in 2008 and US29 billion in 2009. These were about 8.6 per cent of non-oil GDP in the same years. Our estimates complement other findings from around the world that confirm substantial contribution of housewives to the economy. These contributions have gone unrecorded and not compensated in most countries. At a minimum, housewives can be insured against basic contingencies of life such has health problems, poverty and disabilities and supported in old age. Our work and other studies do provide the economic and social arguments for costing and putting into practice the long overdue support for housewives; they have earned it

    Optimal Placement of Capacitors for Get the Best Total Generation Cost by Genetic Algorithm

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    Economic Dispatch(ED) is one of the most challenging problems of power system since it is difficult to determine the optimum generation scheduling to meet the particular load demand with the minimum fuel costs while all constraints are satisfied. The objective of the Economic Dispatch Problems (EDPs) of electric power generation is to schedule the committed generating units outputs so as to meet the required load demand at minimum operating cost while satisfying all units and system equality and inequality constraints. In this paper, an efficient and practical steady-state genetic algorithm (SSGAs) has been proposed for solving the economic dispatch problem. The objective is to minimize the total generation fuel cost and keep the power flows within the security limits. To achieve that, the present work is developed to determine the optimal location and size of capacitors in transmission power system where, the Participation Factor Algorithm and the Steady State Genetic Algorithm are proposed to select the best locations for the capacitors and determine the optimal size for them

    Comparison of psychological health in mothers of diabetic and Leukemic children and control group

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    Background: Parents' psychological health is one of the most important factors to obtain health in children with chronic disease. Objectives: In this paper, we intended to evaluate and compare psychological health in parents of type 1 diabetes mellitus (T1DM) and Leukemic children with control group and estimate the effect of the type of disease on parents' psychological health and if possible recommend means to improve it. Patients and Methods: Three groups of mothers (30 people per group) were evaluated. T1DM children's mothers, Leukemic children's mothers, and control group were chosen from mothers of children who came to Hazrat Aliasghar Emergency Room without any underlying diseases. The samples were asked to fill SCL-90-R and FBIS questionnaires. In addition, other forms were filled for their demographic characteristics. Results: The abbreviation (GSI) score in Leukemic children's mothers was higher than T1DM children's mothers and both groups had higher GSI compared with the control group. Conclusions: Parental functioning and wellbeing are important aspects of a family adaptation to chronic pediatric conditions. Moreover, psychological interventions were recommended to patients. © 2015, Iranian Society of Pediatrics

    Applying Bayesian Optimization with Gaussian Process Regression to Computational Fluid Dynamics Problems

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    Bayesian optimization (BO) based on Gaussian process regression (GPR) is applied to different CFD (computational fluid dynamics) problems which can be of practical relevance. The problems are i) shape optimization in a lid-driven cavity to minimize or maximize the energy dissipation, ii) shape optimization of the wall of a channel flow in order to obtain a desired pressure-gradient distribution along the edge of the turbulent boundary layer formed on the other wall, and finally, iii) optimization of the controlling parameters of a spoiler-ice model to attain the aerodynamic characteristics of the airfoil with an actual surface ice. The diversity of the optimization problems, independence of the optimization approach from any adjoint information, the ease of employing different CFD solvers in the optimization loop, and more importantly, the relatively small number of the required flow simulations reveal the flexibility, efficiency, and versatility of the BO-GPR approach in CFD applications. It is shown that to ensure finding the global optimum of the design parameters of the size up to 8, less than 90 executions of the CFD solvers are needed. Furthermore, it is observed that the number of flow simulations does not significantly increase with the number of design parameters. The associated computational cost of these simulations can be affordable for many optimization cases with practical relevance

    Optimal Placement of Capacitors for Get the Best Total Generation Cost by Genetic Algorithm

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    Economic Dispatch(ED) is one of the most challenging problems of power system since it is difficult to determine the optimum generation scheduling to meet the particular load demand with the minimum fuel costs while all constraints are satisfied. The objective of the Economic Dispatch Problems (EDPs) of electric power generation is to schedule the committed generating units outputs so as to meet the required load demand at minimum operating cost while satisfying all units and system equality and inequality constraints. In this paper, an efficient and practical steady-state genetic algorithm (SSGAs) has been proposed for solving the economic dispatch problem. The objective is to minimize the total generation fuel cost and keep the power flows within the security limits. To achieve that, the present work is developed to determine the optimal location and size of capacitors in transmission power system where, the Participation Factor Algorithm and the Steady State Genetic Algorithm are proposed to select the best locations for the capacitors and determine the optimal size for them

    Optimal Placement of Capacitors for Get the Best Total Generation Cost by Genetic Algorithm

    Get PDF
    Economic Dispatch(ED) is one of the most challenging problems of power system since it is difficult to determine the optimum generation scheduling to meet the particular load demand with the minimum fuel costs while all constraints are satisfied. The objective of the Economic Dispatch Problems (EDPs) of electric power generation is to schedule the committed generating units outputs so as to meet the required load demand at minimum operating cost while satisfying all units and system equality and inequality constraints. In this paper, an efficient and practical steady-state genetic algorithm (SSGAs) has been proposed for solving the economic dispatch problem. The objective is to minimize the total generation fuel cost and keep the power flows within the security limits. To achieve that, the present work is developed to determine the optimal location and size of capacitors in transmission power system where, the Participation Factor Algorithm and the Steady State Genetic Algorithm are proposed to select the best locations for the capacitors and determine the optimal size for them

    Plasmon-Mediated Drilling in Thin Metallic Nanostructures

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    Tetrahedral nanopyramids made of silver and gold over ITO/glass surfaces are fabricated. Our protocol is based on nanosphere lithography (NSL) with the deposition of thicker metal layers. After removing the microspheres used in the NSL process, an array of metallic tetrahedral nanostructures of ~350-400 nm height is formed. The reported procedure avoids the use of any stabilizing surfactant molecules that are generally necessary to segregate the individual particles onto surfaces. We focus here on the optical and the physical properties of these plasmonic surfaces using near-field spectroscopy in conjunction with finite difference time domain (FDTD) modeling of the electric field. Remarkably, FDTD shows that the localized surface plasmon resonance is confined in the plane formed by the edges of two facing pyramids that is parallel to the polarization of the impinging excitation laser. The variable gap between the edges of two adjacent pyramids shows a broader localized surface plasmon and larger specific surface as opposed to the usual nanotriangle array. Localized enhancement of the electric field is experimentally investigated by coating the plasmonic surface with a thin film of photosensitive azopolymer onto the surface of the nanopyramids. The reported deformation upon radiation of the surface topography is visualized by atomic force microscopy and suggests the potentiality of these 3D nanopyramids for near-field enhancement. This last feature is clearly confirmed by surface-enhanced Raman scattering measurement with 4-nitrothiophenol molecules deposited on the pyramid platforms. The potentiality of such 3D nanostructures in plasmonics and surface spectroscopy is thus clearly demonstrated

    Investigation of the Numerical Methodology of a Model Wind Turbine Simulation

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    The present work aims to investigate different methodologies for the numerical simulation of an upwind three-bladed wind turbine; which is supposed to be a base model to simulate icing in cold climate windmills. That is a model wind turbine for which wind tunnel tests have been completed at the Norwegian University of Science and Technology (NTNU). Using the assumption of axisymmetry, one-third of rotor has been modeled and periodic boundaries applied to include the effects of other blades. Then the full rotor was studied with transient simulation. To take in the effects of wind turbine wakes, the wind tunnel entrance and exit have been considered 4 and 5 diameters upstream and downstream of the rotor plane, respectively. Furthermore, the effects of tower and nacelle are included in a full-scale transient model of the wind tunnel. Structured hexa mesh has been created and the mesh is refined up to y+=1 in order to resolve the boundary layer. The simulations were performed using standard k-ε, Shear Stress Transport (SST) model and a sophisticated model Scale-Adaptive Simulation (SAS)-SST to investigate the capability of turbulence models at design and off-design conditions The performance parameters, i.e., the loads coefficients and the wake behind the rotor were selected to analyze the flow over the wind turbine. The study was conducted at both design and off-design speeds. The near wake profiles resulted from the transient simulation match well with the experiments at all the speed ranges. For the wake development modelling at high TSR, the present simulation needs to be improved, while at low and moderate TSR the results match with the experiments at far wake too. The agreement between the measurements and CFD is better for the power coefficient than for the thrust coefficient
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