The influence of wildlife water developments and vegetation on rodent abundance in the Great Basin Desert

Rodent communities have multiple functions including comprising a majority of the mammalian diversity within an ecosystem, providing a significant portion of the available biomass consumed by predators, and contributing to ecosystem services. Despite the importance of rodent communities, few investigations have explored the effects of increasing anthropogenic modifications to the landscape on rodents. Throughout the western United States, the construction of artificial water developments to benefit game species is commonplace. While benefits for certain species have been documented, several researchers recently hypothesized that these developments may cause unintentional negative effects to desert-adapted species and communities. To test this idea, we sampled rodents near to and distant from wildlife water developments over 4 consecutive summers. We employed an asymmetrical before-after-control-impact (BACI) design with sampling over 4 summers to determine if water developments influenced total rodent abundance. We performed an additional exploratory analysis to determine if factors other than free water influenced rodent abundance. We found no evidence that water developments impacted rodent abundance. Rodent abundance was primarily driven by vegetation type and year of sampling. Our findings suggested that water developments on our study area do not represent a significant disturbance to rodent abundance and that rodent abundance was influenced by the vegetative community and temporal factors linked to precipitation and primary plant production. Our findings represent one of the 1st efforts to determine the effects of an anthropogenic activity on the rodent community utilizing a manipulation design

Hardware Efficient Massive MIMO Systems with Optimal Antenna Selection

An increase in the number of transmit antennas (M) poses an equivalent rise in the number of Radio Frequency (RF) chains associated with each antenna element, particularly in digital beamforming. The chain exhibits a substantial amount of power consumption accordingly. Hence, to alleviate such problems, one of the potential solutions is to reduce the number of RFs or to minimize their power consumption. In this paper, low-resolution Digital to Analogue Conversion (DAC) and transmit antenna selection at the downlink are evaluated to favour reducing the total power consumption and achieving energy efficiency in mMIMO with reasonable complexity. Antenna selection and low-resolution DAC techniques are proposed to leverage massive MIMO systems in free space and Close In (CI) path-loss models. The simulation results show that the power consumption decreases with antenna selection and low-resolution DAC. Then, the system achieves more energy efficiency than without low-resolution of DAC and full array utilization

Distance aware transmit antenna selection for massive MIMO systems

Multiple-Input Multiple-Output (MIMO) antenna selection is a signal processing techinique by which the Radio Frequency (R.F.) chain components are switched to their corresponding subset of antennas. Antenna selection revolves the complexity and power consumption of R.F. transceivers. This paper proposes an optimal antenna selection technique for multiple radio component type massive MIMO, which combines two selction techniques by exploiting the minimum signal-to-noise ratio (SNR) at the cell edge and dynamic channel condition due to mobility. After an adaptive selection has been made, the same number selection has been made, the same number of R.F. components are active, and the rest are set to sleeping mode to apply fractional transmit power re-allocation at sub 6GHz and mm Wave frequencies. Accordingly, the branch with better signal quality among the array is chosen and added in iteration till the selected value is attained; however, re-selection still boosts E.E. at the cost of the total rate. The results show that the algorithm over performs the random selection, achieving better energy efficiency that full array utilization and random selection. Moreover, capacity reduction due to selection is compensated by applying nonlinear preceding at the cost of complexity.&nbsp

ENERGY EFFICIENT ADAPTIVE SECTOR-BASED USER CLUSTERING ALGORITHM FOR CELLULAR NETWORK

In this paper, we propose an adaptive and multi-sector-based user clustering algorithm which increases energy efficiency in a cellular network. Adaptive sectoring with dynamically changing sector angles is illustrated with a number of randomly distributed mobile stations. Transmitted power is equally shared by sectors before adaptive user clustering. The sector angles vary from 30 to 360 degrees by merging neighboring sectors and a sector is switched off till the user density exceeds a threshold (Td). The Td value is computed from the total number of users that the cell can accommodate over the area of the cell. The sectors with less than Td density exhibits transmit power which approaches to zero or sleeping state and so that the cumulative power is saved. Simulation results show that an average of 45% to 50% energy can be saved in 10 iterations.International Foundation for TelemeteringProceedings from the International Telemetering Conference are made available by the International Foundation for Telemetering and the University of Arizona Libraries. Visit http://www.telemetry.org/index.php/contact-us if you have questions about items in this collection

Aerospace image processing with the use of the field of fractals dimensions

Рассмотрена возможность анализа аэрокосмических изображений с использованием поля фрактальных размерностей. Оценено влияние размера "окна" и величины "скачка" на параметры поля фрактальных размерностей.Розглянута можливість аналізу аерокосмічних зображень з використовуванням поля фрактальних розмірностей. Оцінено вплив розміру "вікна" і величини "стрибка" на параметри поля фрактальних розмірностей.Possibility of analysis of aerospace images is considered with the use of the field of fractals dimensions. Influence of ”window” size and of "jump" extent is appraised on the parameters of the field of fractals dimensions