Accounting for real meteorological conditions at the time of UAV flight mission planning

The article is dedicated to the the problem of not considering the real meteorological conditions in planning the flight task of the unmanned aerial vehicle (UAV) A1-CM Furia . Unmanned aerial system(UAS) A1-CM Furia has been developed and manufactured by LLC SPC Athlon Avia since 2014. Within 2019-2020, the UAS passed a full spectrum of state tests and was adopted by the Armed Forces of Ukraine. The main criteria that this UAS meets are the detection and tracking of enemy objectives, equipment maintenance and target reconnaissance. Among the peculiarities of UAV application are performance of tasks in adverse meteorological conditions, the use of radio-electronic suppression by the opposing parties, significant spatial characteristics of the areas of responsibility of units and subdivisions for reconnaissance and engagement. The change in the charge current of the battery depending on the air temperature and the change in the charge current of the battery depending on the wind speed in different meteorological conditions were analyzed in the article. The article presents experimental results that determine the order of current consumption for battery time depending on meteorological factors, such as wind speed and air temperature. These results indicate that the UAV A1-CM Furia during the task accomplishment can not meet the flight characteristics that are defined in the flight operation manual UAS (FAM). The FAM does not separate the differences in the use of UAV in different meteorological conditions. This causes possible errors in calculating the maximum length of the route and the maximum possible time in the air. In the article it was proposed to develop a correction for the use of UAV depending on changes in wind speed and temperature . During the assessing of possible corrections for the use of UAV at different wind speeds and air temperatures, the accuracy of determining the possible values of the maximum route length and maximum time of UAV in the air allows us to calculate more accurate data for future tasks accomplisment. Experimental methods of calculating corrections took a large part in the specific study of information without taking into account the real meteorological conditions while planning the flight task of the UAV A1-CM Furia. The obtained results show that without further consideration of meteorological conditions while planning a flight task there may be inaccuracies.

Theoretical analysis of the inverse Edelstein effect at the LaAlO3 / SrTiO3 interface with an effective tight-binding model: Important role of the second dxy subband

The two-dimensional electron gas formed at interfaces between SrTiO3 and other materials has attracted much attention since extremely efficient spin-to-charge current conversion has been recently observed at these interfaces. This has been attributed to their complicated quantized multi-orbital structures with a topological feature. However, there are few reports quantitatively comparing the conversion efficiency values between experiments and theoretical calculations at these interfaces. In this study, we theoretically explain the experimental temperature dependence of the spin-to-charge current conversion efficiency using an 8×8 effective tight-binding model considering the second dxy subband, revealing the vital role of the quantization of the multi-band structure.

Irreversible Thermodynamics at Surfaces: Inverse Edelstein Effect for Topological Insulator

We employ Onsager’s irreversible thermodynamics (IrTh) to study the Inverse Edelstein effect (IEE) for a non-magnetic material (NM) adjacent to a topological insulator (TI) with a strong spin-orbit interaction. The TI surface state region is treated as quasi two-dimensional (2d). For the IEE, the source is a 3d spin flux incident from the NM that converts, at the NM/TI interface, to a quasi-2d charge current in the TI. For the Edelstein Effect (EE), the source is a quasi-2d charge flux incident from the TI that converts, at the interface, to a three-dimensional (3d) spin flux in the NM. For strong spin-orbit coupling, as considered here, when the 3d spin flux crosses to the 2d TI, the quasi-2d charge current is produced along with a quasi-2d spin accumulation. (For weak spin-orbit coupling, production of charge current and of spin accumulation are distinct processes.) We compute the associated rates of heating.

A New Standard Design of Lightning Protection System for Offshore and Nearshore Oil and Gas at Tropic Area

Based on NFPA-780, offshore platforms, which made from metal framework of a structure are thought of as "grounded" to the ocean and therefore are not needed to be installed external Lightning Protection System (LPS). PHE ONWJ which located at offshore tropic area has implemented NFPA 80 but still experience lightning hit. It generated fire at vent stack andcause operations interference. So that, the objective of this study is to redesign LPS for tropic area. Firstly, the methodology for this study was conducting literature review from previous researches for lightning protection system at tropic area and researches which underlyingNFPA-780. The literature reviews were focusing on lightning characteristic for tropic area andthe lightning density data from local lighting strike monitors surrounding PHE ONWJ. The result of literature reviews would be the basis of lightning strike event reviews in PHE ONWJ facilities. Subsequently, the authors conducted the equipment layout review using rolling sphere method based on previous lightning strike location. Lastly, Authors proposed the recommendationsfor typical LPS for oil and gas at tropic area. Based on literature reviews,lightning characteristic at tropic area has peak strike current twice the sub-tropic and longer "tail" so that the charge current is larger. Larger the charge current of lightning cause greaterimpact into metal structure that is metal melting. Based on NFPA 780/2011, the offshore platform, which is made by metal, and vessel with minimum thickness 4.8 mm are self-protected. However, based on calculation, with the characteristic of lightning at tropic area, the recommendedminimum vessel thickness is 10 mm. This calculation reinforces the fact that standard of Lightning Protection System in NFPA 780/2011 is not sufficient to be applied in tropic area like Indonesia. After calculating the tropic lightning strike range using rolling sphere method, it isrecommended to redesign lightning protection system for some locations at offshore platform and near shore facilities of PHE ONWJ.The lightning protections system locations and quantities are depending on the area and the needed protected equipment in it.The installation isincluding extended mast terminal, free standing mast, low inductive Double Shielded Down Conductor(DSDC), Lightning Event Counter (LEC), and good grounding system at the platform.

Major Effective-damping Reduction Achieved by Metallic Coating on YIG Thin Films

Since its discovery, yttrium iron garnet (YIG) has been object of great interest because of its peculiarly low magnetic damping. Magnetic materials with reduced damping promote microwave power efficiency, longer magnon lifetime and longer spin-wave propagation. Owing to research on charge-to-spin current conversion, the control of magnetic damping in ferromagnetic thin films has recently been achieved by inducing charge current on adjacent metal layer with strong spin-orbit coupling (SOC). We report damping reduction in metallized YIG thin films (YIG/Ag/Ni) without the need of applied charge current and suggest that the origin of this unexpected effect is a strengthening of the FMR uniform mode in the YIG layer, due to frequency- and phase-locking that result from self-synchronization mediated by nonzero spin densities transiting the metallic layers.

Non-Linear Thermoelectric Devices with Surface-Disordered Nanowires

We reviewed some recent ideas to improve the efficiency and power output of thermoelectric nano-devices. We focused on two essentially independent aspects: (i) increasing the charge current by taking advantage of an interplay between the material and the thermodynamic parameters, which is only available in the non-linear regime; and (ii) decreasing the heat current by using nanowires with surface disorder, which helps excite localized phonons at random positions that can strongly scatter the propagating phonons carrying the thermal current.