Outage Analysis of Unmanned-Aerial-Vehicle-Assisted Simultaneous Wireless Information and Power Transfer System for Industrial Emergency Applications.

In the scenario of a natural or human-induced disaster, traditional communication infrastructure is often disrupted or even completely unavailable, making the employment of emergency wireless networks highly important. In this paper, we consider an industrial Supervisory Control and Data Acquisition (SCADA) system assisted by an unmanned aerial vehicle (UAV) that restores connectivity from the master terminal unit (MTU) to the remote terminal unit (RTU). The UAV also provides power supply to the ground RTU, which transmits the signal to the end-user terminal (UT) using the harvested RF energy. The MTU-UAV and UAV-RTU channels are modeled through Nakagami-m fading, while the channel between the RTU and the UT is subject to Fisher-Snedecor composite fading. According to the channels' characterization, the expression for evaluating the overall probability of outage events is derived. The impact of the UAV's relative position to other terminals and the amount of harvested energy on the outage performance is investigated. In addition, the results obtained based on an independent simulation method are also provided to confirm the validity of the derived analytical results. The provided analysis shows that the position of the UAV that leads to the optimal outage system performance is highly dependent on the MTU's output power.

Performance Analysis of Wirelessly Powered Cognitive Radio Network with Statistical CSI and Random Mobility.

The relentless expansion of communications services and applications in 5G networks and their further projected growth bring the challenge of necessary spectrum scarcity, a challenge which might be overcome using the concept of cognitive radio. Furthermore, an extremely high number of low-power devices are introduced by the concept of the Internet of Things (IoT), which also requires efficient energy usage and practically applicable device powering. Motivated by these facts, in this paper, we analyze a wirelessly powered underlay cognitive system based on a realistic case in which statistical channel state information (CSI) is available. In the system considered, the primary and the cognitive networks share the same spectrum band under the constraint of an interference threshold and a maximal tolerable outage permitted by the primary user. To adopt the system model in realistic IoT application scenarios in which network nodes are mobile, we consider the randomly moving cognitive user receiver. For the analyzed system, we derive the closed-form expressions for the outage probability, the outage capacity, and the ergodic capacity. The obtained analytical results are corroborated by an independent simulation method.

The impact of the COVID-19 pandemic on the trend of prescribing long-acting injections of paliperidone and risperidone in Central Serbia.

Since the end of 2019, the global spread of COVID-19 has represented a historic event that changed our way of treating patients globally. The use of long-acting injections (LAI) antipsychotics was emphasized. Our goal was to investigate the impact of COVID-19 on the frequency of prescribing LAI and compare it with a period before. All patients (198) who started LAI-risperidone or LAI-paliperidone for the period 2017-2022, in Kragujevac, the city in Central Serbia, were considered. The frequency of prescribing LAI before and during COVID-19 and the total number of prescribed LAI per year were compared. Separately, the frequency of prescribing LAI-R and the frequency of prescribing LAI-P were compared. The significant (p < 0,05) increase in the use of LAI risperidone and paliperidone was in 2020 and 2021 [per year 2017(3), 2018(6), 2019(26), 2020(75), 2021(55), and 2022(33)]. The significant (p < 0,05) increase in monthly and quarterly preparations of LAI paliperidone was in 2020 and 2021 relative to the years before the pandemic. As the pandemic weakened, the inclusion of LAI paliperidone therapy weakened during 2022. A significant increase in usage of LAI risperidone was in 2022, and in 2020 and 2021 was as it was in the period 2017-2019. During COVID-19, especially in years when COVID-19 restriction measures were stricter, there was a significant change in the application method of antipsychotic therapy in favor of LAI. Regardless of the increase in treatment costs, patients' interests and protection were prioritized in the treatment process.

Relationship between incidence of chronic obstructive pulmonary disease and lung cancer as comorbidity in primary health care in two Belgrade communities.

PURPOSE: To investigate the recent trends in the incidence of chronic obstructive pulmonary disease (COPD) and lung cancer as comorbidity in primary health care (Community Health Center, Zemun, Belgrade, which covers two municipalities - Surchin and Zemun), during the period 2014-2017. METHODS: This retrospective study analyzed the incidence of COPD and lung cancer as comorbidity in a 4-year period. Data were derived from the Heliant information system. Descriptive statistics -frequencies and percentages - were used, and differences between groups were tested by x2 test. RESULTS: The number of patients with COPD was slightly, but insignificantly, higher each consecutive year. Lung cancer as comorbidity appeared in about 11% of these patients. As for gender, male and female patients contributed equally to the number of patients with CORD. CONCLUSION: The number of patients with COPD registered in primary health care was similar in all investigated years. Lung cancer as comorbidity was found in a significantly smaller number of these patients.

High performance Fresnel-based photovoltaic concentrator.

In order to achieve competitive system costs in mass-production, it is essential that CPV concentrators incorporate sufficient manufacturing tolerances. This paper presents an advanced concentrator optic comprising a Fresnel lens and a refractive secondary element, both with broken rotational symmetry, an optic producing both the desired light concentration with high tolerance (high acceptance angle) as well as an excellent light homogenization by Köhler integration. This concentrator compares well with conventional Fresnel-based CPV concentrators.

High performance Fresnel-based photovoltaic concentrator.

In order to achieve competitive system costs in mass-production, it is essential that CPV concentrators incorporate sufficient manufacturing tolerances. This paper presents an advanced concentrator optic comprising a Fresnel lens and a refractive secondary element, both with broken rotational symmetry, an optic producing both the desired light concentration with high tolerance (high acceptance angle) as well as an excellent light homogenization by Köhler integration. This concentrator compares well with conventional Fresnel-based CPV concentrators.

Etendue-preserving mixing and projection optics for high-luminance LEDs, applied to automotive headlamps.

By having a single optical element combine the light of several high luminance LEDs, a high luminance light source can be formed, with shape and emission characteristics adaptable to nearly all illumination problems. The illuminance distribution of this virtual source facilitates the generation of the desired intensity pattern via its imaging-stye projection into the far field. This projection is achieved by one refractive and one reflective freeform surface, both calculated simultaneously by the 3D SMS method, which is herein demonstrated for an LED automotive headlamp.