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In recent years, escalating cost of generating electricity, substantial investments with the purpose of building power plants, and environmental pollution related to the power generation have underlined the importance of optimal power supply and demand management. Given that, by employing Long-range Energy Alternatives Planning (LEAP) software, the present study set out to optimize the energy system of Iran through two model capabilities, namely electric sector optimization and simulation. To do so, the energy system was initially evaluated by optimizing Iran's demand for electricity by the Demand Side Management (DSM) scenario. Then, Iran's electricity sector was optimized to generate electricity at the lowest cost by setting emission roof with different scenarios, especially the Optimized scenario. The social cost and GHG emission were evaluated in both steps. The prospective social costs of the electricity generation sector based on Optimized and DSM scenarios were calculated to be 5.1 and 4.8 Billion U.S. Dollars in 2035. Regarding the environmental results of the study, the emission rates of pollutants based on Optimized and DSM scenarios were reported to be144 and 429 MtCO 2 for the same year.

The purpose of this paper was to study the role of the urban land market in the spatial development of Mashhad. In this study, factors such as the status of buying and selling land, standard deviation of habitants' income, changes in green space, land-use realization rate, and building violation formed the indicators for appraising the land market. The MORRIS model was used to evaluate the rate of development of this case study in three general groups, namely economical, social-cultural, and spatial-physical. The TOPSIS model was also used in classifying the development of each urban district. The effect of each development indicator on the general development was attained by using multivariate regression. The results showed that the economical development indicator has the highest effect on total development of the district. Pearson's correlation coefficient was used to study the relationship between each indicator of the urban land market and the development of neighborhoods in this district. The sale indicator for the effect of the urban land market on urban district development was evaluated by the causal modeling method, which has the highest influence on the spatial development in Mashhad. In fact, owing to the price of land in some neighborhoods, selling and buying of land increased - it resulted in land speculation, development of some parts of the district, and reduction of spatial equality among neighborhoods. It is suggested that introducing a more accurate tax system can reduce urban land speculation.

Seismology of stars provides insight into the physical mechanisms taking place in their interior, with modes of oscillation probing different layers. Low-amplitude acoustic oscillations excited by turbulent convection were detected four decades ago in the Sun and more recently in low-mass main-sequence stars. Using data gathered by the Convection Rotation and Planetary Transits mission, we report here on the detection of solar-like oscillations in a massive star, V1449 Aql, which is a known large-amplitude (β Cephei) pulsator.

Taking the pulse of red giants When main-sequence stars like the Sun near the end of their life, they expand to become oscillating red giants. Such evolved stars could in principle provide stringent tests of stellar theory via analysis of radial and non-radial stellar oscillations. Until now it has been unclear whether non-radial modes are observable at all in red giants. De Ridder et al . now report the presence of both radial and non-radial oscillations in over 300 giant stars. For some red giants, mode lifetimes are of the order of a month. Current stellar evolution theory cannot account for these observations. Towards the end of their lives, stars like the Sun expand greatly to become red giant stars that oscillate. Such evolved stars could provide stringent tests of stellar theory through the analysis of radial and non-radial stellar oscillations. Here, the presence of such oscillations in more than 300 giant stars is reported, with mode lifetimes of some of the giants in the order of a month. Towards the end of their lives, stars like the Sun greatly expand to become red giant stars. Such evolved stars could provide stringent tests of stellar theory, as many uncertainties of the internal stellar structure accumulate with age. Important examples are convective overshooting and rotational mixing during the central hydrogen-burning phase, which determine the mass of the helium core, but which are not well understood 1 . In principle, analysis of radial and non-radial stellar oscillations can be used to constrain the mass of the helium core. Although all giants are expected to oscillate 2 , it has hitherto been unclear whether non-radial modes are observable at all in red giants, or whether the oscillation modes have a short or a long mode lifetime 3 , 4 , 5 , 6 , 7 , which determines the observational precision of the frequencies. Here we report the presence of radial and non-radial oscillations in more than 300 giant stars. For at least some of the giants, the mode lifetimes are of the order of a month. We observe giant stars with equally spaced frequency peaks in the Fourier spectrum of the time series, as well as giants for which the spectrum seems to be more complex. No satisfactory theoretical explanation currently exists for our observations.

Friction stir welding as one of the modern methods of solid-state welding of steel sheets and aluminum is a highly regarded industry. In these studies, the experimental design and response surface methodology were used. Optimization of experimental conditions and results which are compared with good agreement between the results was observed. The mechanical properties and ductility of welded plates under optimal conditions were studied. Microhardness testing, metallography, tensile testing, and limiting dome height were used to investigate the mechanical properties and formability limit diagram attached, respectively. The results showed that the heat-affected zone is very small and narrow and not easily distinguished from the base metal. In all tests, the failure of the dome height limit in the area was chaos. In all samples welded with the optimal parameters, tensile failure occurred in the base metal region. Turbulence in the region confirms the presence of WC particles. Experimental design and response surface methodology could introduce an optimal state, and the creation of common defects in the FSW process can prevent the binding strength of the guarantee. But due to the lack of proper stirring in the perturbation area in the samples welded with non-optimized parameters, the strength of the connection is not suitable, and samples were broken from the SZ region.

Over the past few years, the pace of fossil fuel consumption has witnessed an accelerating trend across the world which has been really noticeable especially for the power generation sector. With regard to its global importance, the environment must be also preserved and emissions of pollutants and greenhouse gases (GHGs) as well as environmental costs need to be moderated. Given the urgency of energy preservation and environmental issues, the process of electricity generation should be evaluated. Accordingly, elimination of conditions along with prediction of energy consumption and pollutant emissions have been performed through energy simulation and modeling software tools, e.g., Long-range Energy Alternatives Planning System (LEAP). The energy consumption in thermal power plants for 2035 is estimated to be 209.7, 153.5, and 132.0 Bcm respectively for Reference (REF), Efficiency based on 5-Year National Development Plan (E5P), and Efficiency similar to UK (EUK) scenarios using efficiency improvement scenario of thermal power plants in Iran. GHG emissions for 2035 are thus predicted by 456 . 8 MtCO 2 -eq for the REF scenario, and 332.6 and 285.1 MtCO 2 -eq for the E5P and the EUK ones, respectively. Environmental costs for electricity generation system will also diminish via applying scenarios in this sector and its least amount, that is, US$835.8 million is related to the EUK scenario. Accomplishing goals such as better preservation of fossil resources and the environment will be consequently facilitated through improved efficiency and effectiveness of consumption of energy resources. To meet the objectives of environmental preservation, it is suggested to completely implement development plans and also make attempts to promote the technology of thermal power plants in Iran similar to that in developed countries. This study also compares the findings with those reported in recently published investigations.

The Stellar Seismic Indices database (hereafter SSI) has been developed within the SPACEInn project funded under the UE Seventh Framework Programme (FP7). This data base aims at providing stellar seismic indices of solar-like oscillating stars as well as other stellar indices such as the main characteristics of stellar granulation. These indices are extracted using an automatic method, which is able to derive simultaneously the seismic and granulation parameters. This method was applied to almost all Kepler long-cadence light-curves and to almost all CoRoT targets observed in the faint fields. A total of about 320 000 targets have been analyzed, among which seismic indices and granulation parameters have been extracted for about 18 000 redgiants. In this article, we present the data base content, its interface, as well as some illustrative results.

Inspired by the so appealing example of red giants, where going from a handful of stars to thousands revealed the structure of the eigenspectrum, we inspected a large homogeneous set of around 1860 δ Scuti stars observed with CoRoT. This unique data set reveals a common regular pattern which appears to be in agreement with island modes featured by theoretical non-perturbative treatments of fast rotation. The comparison of these data with models and linear stability calculations suggests that spectra can be fruitfully characterized to first order by a few parameters which might play the role of seismic indices for δ Scuti stars, as Δv and vmax do for red giants. The existence of this pattern offers an observational support for guiding further theoretical works on fast rotation. It also provides a framework for further investigation of the observational material collected by CoRoT ([1]) and Kepler ([2]). Finally, it sketches out the perspective of using δ Scuti stars pulsations for ensemble asteroseismology

The growing amount of seismic data available from space missions (SOHO, CoRoT, Kepler, SDO,…) but also from ground-based facilities (GONG, BiSON, ground-based large programmes…), stellar modelling and numerical simulations, creates new scientific perspectives such as characterizing stellar populations in our Galaxy or planetary systems by providing model-independent global properties of stars such as mass, radius, and surface gravity within several percent accuracy, as well as constraints on the age. These applications address a broad scientific community beyond the solar and stellar one and require combining indices elaborated with data from different databases (e.g. seismic archives and ground-based spectroscopic surveys). It is thus a basic requirement to develop a simple and effcient access to these various data resources and dedicated tools. In the framework of the European project SpaceInn (FP7), several data sources have been developed or upgraded. The Seismic Plus Portal has been developed, where synthetic descriptions of the most relevant existing data sources can be found, as well as tools allowing to localize existing data for given objects or period and helping the data query. This project has been developed within the Virtual Observatory (VO) framework. In this paper, we give a review of the various facilities and tools developed within this programme. The SpaceInn project (Exploitation of Space Data for Innovative Helio- and Asteroseismology) has been initiated by the European Helio- and Asteroseismology Network (HELAS).

Rotation is thought to drive cyclic magnetic activity in the Sun and Sun-like stars. Stellar dynamos, however, are poorly understood owing to the scarcity of observations of rotation and magnetic fields in stars. Here, inferences are drawn on the internal rotation of a distant Sun-like star by studying its global modes of oscillation. We report asteroseismic constraints imposed on the rotation rate and the inclination of the spin axis of the Sun-like star HD 52265, a principal target observed by the CoRoT satellite that is known to host a planetary companion. These seismic inferences are remarkably consistent with an independent spectroscopic observation (rotational line broadening) and with the observed rotation period of star spots. Furthermore, asteroseismology constrains the mass of exoplanet HD 52265b. Under the standard assumption that the stellar spin axis and the axis of the planetary orbit coincide, the minimum spectroscopic mass of the planet can be converted into a true mass of [Formula], which implies that it is a planet, not a brown dwarf.