In this paper, we investigate the feasibility of using the existing cellular infrastructure for drone operations. To this end, we derive an exact expression for the coverage probability of the ground and drone users by considering a practical cell association strategy. Our analytical framework includes base station (BS) height and antenna radiation pattern, drone antenna directivity, and the im...

Due to the impelling urgency of plant conservation and the increasing availability of high resolution spatially interpolated (e.g. climate variables) and categorical data (e.g. land cover and vegetation type), many recent studies have examined relationships among plant species distributions and a diversified set of explanatory factors; nevertheless, global and regional patterns of endemic plant...

The area and elevation of the Tibetan Plateau over time has directly affected Asia's topography, the characteristics of the Asian monsoon, and modified global climate, but in ways that are poorly understood. Charting the uplift history is crucial for understanding the mechanisms that link elevation and climate irrespective of time and place. While some palaeoelevation data are available for sou...

A downlink performance of deploying WiMAX (IEEE802.16a) both from High Altitude Platforms (HAPs) and from terrestrial base stations sharing the 3.5GHz band is presented. It is shown how these two wireless communication configurations can coexist with either adjacent or overlaying coverage areas. The performance of each deployment is affected by factors such as transmission power, antenna beamwi...

Sexual systems, particularly dioecy, and the habit correlations were examined for 3052 native angiosperms in Taiwan and 689 species from its outlying Orchid Island, and compared among different vegetation types. The majority of angiosperms in Taiwan are hermaphrodites (74.4%, N = 2272), followed by monoecious taxa (11.2%, N = 341), and then dioecious taxa (7.9%, N = 240) and polygamous taxa (6....

with respect to wide distribution of a. sieberi besser in iran, various studies have been done on its habitats and different ecological properties have been referred as effective factors in establishment of this species. in this research, we tried to study the ecological range of a. sieberi and its relationship with vegetative characteristics. therefore, climate properties including annual prec...

This article addresses the visual area coverage problem using a team of Unmanned Aerial Vehicles (UAVs). The UAVs are assumed to be equipped with a downward facing camera covering all points of interest within a circle on the ground. The diameter of this circular conic-section increases as the UAV flies at a larger height, yet the quality of the observed area is inverse proportional to the UAV’...