Passive solar systems such as solar chimneys need solar radiation in order to work. Therefore, they cannot present stable natural ventilation when solar energy vanishes: to have a more robust and stable condition, solar energy should be stored during the day and released back during the night. Phase change materials can save additional thermal energy during the day and release it during the nig...

A regional reference model of total electron content (TEC) was constructed using data from the GPS Earth Observation Network (GEONET), which consists of more than 1000 Global Positioning System (GPS) satellite receivers distributed over Japan. The data covered almost one solar activity period from April 1997 to June 2007. First, TECs were determined for 32 grid points, expanding from 27 to 45 N...

The photodegradation of Direct Blue 258, a member of the group of azo dyes which are commonly used in the various branches of the industry, was studied. The photostability of this dye was not previously surveyed. Photocatalytic degradation method was evaluated. The both light source include solar simulated (UV 400 W lamp) and sun light (E= 400 W/m2) and titanium dioxide nanoparticles were used ...

The photodegradation of Direct Blue 258, a member of the group of azo dyes which are commonly used in the various branches of the industry, was studied. The photostability of this dye was not previously surveyed. Photocatalytic degradation method was evaluated. The both light source include solar simulated (UV 400 W lamp) and sun light (E= 400 W/m2) and titanium dioxide nanoparticles were used ...

Virtual surfaces discussed in the paper are sets of input data of the geometrical model of soil bidirectional reflectance in the optical domain which predict the reflectance behaviour of rough soil surfaces in any illumination and viewing conditions. Equal-sized opaque spheroids lying on a freely sloping plane, describe the soil surface. They are absorbed into the ground of the slope plane havi...

The virtual globe is the default visualization for Digital Earth applications, but it can only show one half of the Earth. This article introduces user-adjustable, on-the-fly projection of georeferenced raster images for web mapping and web GIS applications. This technique allows users to center a map on arbitrary locations, while still seeing the entire Earth surface. Modern web mapping librar...

In order to obtain the best performance of the solar air heaters, it is necessary to find optimum performance conditions. The aim of this research paper is to achieve optimum conditions, by comparing single and double pass solar air heaters. Also, a brief review study of various related research works of all scenarios for a single and double pass and packed bed (including particle technologies)...

In this paper, we show how standard GIS operations like the complement, union, intersection, and buffering of maps can be made more flexible by using fuzzy set theory. In particular, we present a variety of algorithms for operations on fuzzy raster maps, focusing on buffer operations for such maps.

soil erosion is a serious environmental problem in vazroud watershed, which is located in the centre of the mazandaran province, iran. unfortunately, vazroud watershed like most iran watersheds don’t have recorded data and erosion and sedimentation gages to research, monitor and model soil erosion at large watershed. in order to assess the soil erosion risk, soil erosion modeling at the watersh...