Browsing by Author "Apaza, Joab"
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Item Restricted Development of two UAVs for volcano studies in southern Peru(Institute of Electrical and Electronics Engineers, 2017-10) Apaza, Joab; Scipión, Danny; Lume, Diego; Saito, CarlosThe development of Unmanned Aerial Vehicles (UAVs) has gained importance over the last few years due to the innovations brought to farming, architecture, and/or medicine. A novel field where they have been used is volcanology for its long-distance control and the possibility to add multiple sensors for sensing volcano parameters. Two UAVs will be constructed: a multi-rotor (quadcopter) and a fix wing airplane for studying the most active volcano in Peru, the Ubinas. The objective is to get important and useful volcano data without risking the lives of researchers. The quadcopter will be used for image capturing and video recording of the plume, while the airplane will fly close or through to the volcanic plume measuring temperature, humidity, carbon dioxide, sulfuric dioxide, and hydrogen sulfide.Item Open Access Implementation of a UAV-aided calibration method for a mobile dual-polarization weather radar(Elsevier, 2024-06) Buckingham, Giorgio; De La Cruz, Mario; Scipión, Danny; Espinoza Guerra, Juan Carlos; Apaza, Joab; Kemper, GuillermoWeather radar calibration is a crucial factor to be considered for quantitative applications, such as QPE (Quantitative Precipitation Estimation), which is used as input for weather risks management. The present work proposes a novel approach to the end-to-end radar calibration method through the characterization of the radar weighting functions. These are Gaussian functions that model an additional attenuation factor to the radar received power. This approach, based on the inclusion these parameters, allow the obtainment of a calibrated equivalent reflectivity factor expression for a Doppler dual-polarization weather radar that operates in the X band. To calculate these parameters, a UAS (Unmanned Aircraft System) was implemented for suspending the calibration target with a well-defined cross-section and for measuring its inclination due to wind using an IMU (Inertial Measurement Unit). From its measurements, the position of the target can be estimated, which is essential to the characterization of the weighting functions. Their inclusion within the radar equation, alongside the implementation of the angular measurement system highlight the innovation to the traditional radar calibration methodology that does not contemplate them from the explored state-of-the-art. The reflectivity was compared with the measurements from a disdrometer for a moderate rain event. An average reflectivity difference of 0.75 dBZ and a percent bias of 3.3 % were obtained between the expected and estimated measurements when including these functions compared to the 1.51 dBZ and –62.7 % obtained when disregarding them. These experimental results point out that the proposed method can deliver superior accuracy in the reflectivity estimation.Item Open Access On new two-dimensional UHF radar observations of equatorial spread F at the Jicamarca Radio Observatory(Springer Open, 2023-08-09) Rodrigues, F.S.; Milla, M.A.; Scipión, Danny; Apaza, Joab; Kuyeng, Karim; Sousasantos, J.; Massoud, A.A.; Padin, C.We describe a mode for two-dimensional UHF (445 MHz) radar observations of F-region irregularities using the 14-panel version of the advanced modular incoherent scatter radar (AMISR-14). We also present and discuss examples of observations made by this mode. AMISR-14 is installed at the Jicamarca Radio Observatory (JRO, 11.95°S, 76.87°W, ~ 0.5° dip latitude) in Peru and, therefore, allows studies of ionospheric irregularities at the magnetic equator. The new mode takes advantage of the electronic beam-steering capability of the system to scan the equatorial F-region in the east–west direction. Therefore, it produces two-dimensional views of the spatial distribution of sub-meter field-aligned density irregularities in the magnetic equatorial plane. The scans have a temporal resolution of 20 s and allow observations over a zonal distance of approximately 400 km at main F-region heights. While the system has a lower angular and range resolution than interferometric in-beam VHF radar imaging observations available at Jicamarca, it allows a wider field-of-view than that allowed with the VHF system. Here, we describe the mode, and present and discuss examples of observations made with the system. We also discuss implications of these observations for studies of ESF at the JRO.Item Open Access Preliminary AMISR-14 radar observations of F-region incoherent backscatter echoes at the Jicamarca Radio Observatory (JRO)(2022 CEDAR Workshop, 2022-06) Apaza, Joab; Kuyeng, Karim; Flores, Roberto; Milla, M.; Rodrigues, F. S.; Scipión, DannyA 14-panel Advanced Modular Incoherent Scatter Radar (AMISR-14) was installed at the Jicamarca Radio Observatory (IGP- JRO) in 2014. Because of its size, this radar was mainly used to observe coherent echoes such as those produced by the Equatorial Electrojet (EEJ) and Equatorial Spread F (ESF). However, the radar operation was intermittent until 2019 when repairs started to make the radar fully operational. Now, AMISR-14 runs regularly in parallel with the main Jicamarca radar in the JULIA (Jicamarca Unattended Long-term studies of the Ionosphere and Atmosphere) mode to monitor the Equatorial Spread F activity. More recently, we found that running these experiments with a more stable peak power, we have been able to detect not only coherently scatter (CS) signals but also what seems to be incoherently scattered (IS) echoes from the F-region ionosphere. In this poster, we will present some examples of the experiments we have been conducting with AMISR-14. More specifically, we will present and discuss examples of these interesting ISR-like echoes observed with AMISR-14 pointing in different directions along the E-W plane.Item Restricted Unmanned aircraft system for andean volcano monitoring and surveillance(Institute of Electrical and Electronics Engineers, 2019-09-26) Flores, Andres; Scipión, Danny; Saito, Carlos; Apaza, Joab; Milla, MarcoThe design, construction, and field testing of an unmanned aircraft system to monitor high altitude volcanoes is described in this paper. The system must be able to fly above the crater of the volcano and acquire important information such as images, video, and concentration of gases in order to assess potential risks to nearby population. The system must be able to fly above 6000 meters above sea level autonomously with telemetry data transmitted up to 7 km away. All aspects of the system were developed considering the extreme conditions at which the aircraft was subjected. Field experiments were accomplished on two volcanoes in Peru, being one of them currently under eruption.