درخت حوزه‌های تخصصی

The contribution of migration to urbanisation and urban population growth Internal migration, and net migration to urban areas in particular, drives the urbanisation of a country’s population. Rapid overall population growth often overlaps with rapid urbanisation, creating especially fast urban population growth. Rural-urban migration continues to attract much interest, but also growing concern. Migrants are often blamed for increasing urban poverty, but not all migrants are poor. In many cities, however, migrants form a large proportion of the urban poor with whom they share income and non-income disadvantages, including difficulties in finding adequate housing and in accessing services. Like the majority of the urban poor, they work long hours in low-paid, insecure and unsafe jobs and are exposed to a wide range of environmental hazards because most low-income and informal settlements lack basic infrastructure. In many cases when urban governments try to reduce or control rural–urban migration, this also affects low-income residents and not just migrants.This raises the question of whether policies that specifically target migrants in urban centres are desirable and possible.

One of the main concerns of today's world is the reduction of non-renewable energies and environmental pollution caused by them in buildings, which can be controlled by saving and optimizing energy consumption. On the other hand, global climate change and its local and regional effects are important in buildings energy management policies. To this end, identifying and exploiting passive systems and climate-friendly design strategies are one of the cheap and sustainable solutions in this regard. The present study examined the use of soil thermal potentials and earth-sheltered design as one of the practical solutions for providing thermal comfort and reducing energy consumption in hot and dry climates and case studied “Shahdad Desert”. Various active and passive techniques are currently used throughout the world to reduce energy consumption, some of which have been common from the past to the present such as the construction of buildings in the shelter of earth, like the Iranian native architecture. This study empirically and practically investigated the effect of the depth of a building in the soil on the rate of cooling and heating energy consumption. The information required for the construction site of the earth-sheltered building was obtained by conducting a field survey in the Shahdad Desert. It was further suggested to build a tourist residence by taking refuge in the heart of the Kaluts in the hot and dry climates of Shahdad. By moving the designed building inside Kalut, the rate of cooling and heating energy consumption of the building during the year was calculated and the results showed that changing the depth of the earth-sheltered building did not have much effect on heating energy, but as it approached the earth edges, its cooling energy increased. As the building left the earth, the total cooling and heating energy consumption increased dramatically.