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This study is an attempt to develop ecotourism in Nehbandan County, in the South Khorasan Province, Iran, by representing unknown areas that have tourism potential. The most important obstacle in the development of tourism industry is the lack of strong marketing plans, tourism management, accommodations for overnight and long stays, and medical and health clinic in the desert. This is a qualitative, exploratory case study investigating the status of environmental, sociocultural, and economic impacts of ecotourism development on the native people's livelihood in Nehbandan County in Iran. The methodology is based on field observations, secondary data sources, and field survey. It is an interpretive approach that avoids numbers but focuses on issues linked to culture and nature. In the present study, the grounded theory was used to perform data analysis. Based on the findings, ecotourism has undoubtedly proven to be an effective environmental conservation tool in the study site and enables local people to increase their livelihood security through employment in activities relating to ecotourism and the development of rural livelihood. [ABSTRACT FROM AUTHOR]

Locating a fault in double-circuit transmission lines is a challenging task due to the mutual coupling effects between adjacent circuits of the line. Also, performance of impedance-based fault location schemes for double-circuit lines is adversely affected by fault resistance. Accurate fault location in double-circuit lines can be achieved if fault location schemes utilize reliable communication links. However, the communication links are not available or enabled in all transmission lines. To overcome such difficulty in fault location in double-circuit lines, a new fault location scheme is proposed for double-circuit transmission lines by using voltages and currents data extracted from single-end of the line. Only the negative-sequence current and voltage phasors during the fault are processed for calculating the fault location. The proposed fault location formula is derived by applying the Kirchhoff's voltage law around the parallel circuits and shunt capacitances loops. Obtained formula is applicable for all types of unbalanced faults and accordingly classification of fault types and phase selection are not required. The proposed scheme is immune to the fault resistance and insensitive to mutual coupling effects. Evaluation results verify that the accuracy of the proposed algorithm is very high under various fault resistances, fault locations, and fault types. [ABSTRACT FROM AUTHOR]

The present study deals with the microstructural evolution and mechanical properties of AZ31 magnesium alloy processed throughout the novel hot constrained compression (HCC) method. AZ31 core specimens constrained by steel sleeves were compressed in the temperature range of 100 to 600 °C at 0.1 s−1 strain rate, up to true strain of 0.6 mm/mm. Similarly, simple compression (SC) tests were carried out on the AZ31 specimens to compare with the HCC ones. The AZ31 specimens failed under SC while the HCC process was successfully conducted without any sign of failure. This phenomenon is attributed to the hydrostatic pressure imposed by the sleeve steel. Moreover, microstructure characterization revealed that the greater strain accommodation in the HCC case is a result of grain refinement due to severe twinning and preceded dynamic recrystallization (DRX) at low and high temperatures, respectively. Nonetheless, the HCC process beyond 460 °C led to grain growth and coarser microstructure as compared to the SC counterparts. Mechanical properties of processed specimens were investigated at room temperature using shear punch tests. Results indicated that while shear strength and formability of HCC products are premier at low temperature deformation, they are attenuated by increasing the temperature beyond 460 °C. This phenomenon is mainly attributed to the different grain size distribution and the effects of γ precipitants. [ABSTRACT FROM AUTHOR]

Distance relay identifies the type and location of fault by measuring the transmission line impedance. However, any other factors that cause miscalculating the measured impedance make the relay detect the fault in incorrect location or do not detect the fault at all. One of the important factors which directly increases the measured impedance by the relay is fault resistance. Another factor that indirectly changes the impedance of the transmission line is static synchronous compensator (STATCOM). When a fault occurs, measured signals by the relay change due to the variation of current injected by the STATCOM and it makes the calculated impedance to be incorrect. This paper provides a method based on the combination of distance and differential protection. At first, faulty transmission line is detected according to the current data of buses. After that the fault location is calculated using the proposed algorithm on the transmission line. This algorithm is based on active power calculation of the buses. Fault resistance is calculated from the active powers, and its effect will be deducted from calculated impedance by the algorithm. Furthermore, by choosing the appropriate data bus, the effect of STATCOM is eliminated and fault location will be detected. [ABSTRACT FROM AUTHOR]

The original version of this article contained a mistake. [ABSTRACT FROM AUTHOR]