Estimation of Wind Velocity on Flexible Unmanned Aerial Vehicle Without Aircraft Parameters

This research project estimated the wind velocity of a small flexible-wing Unmanned Aerial Vehicle using a software developed the analysis of the data collected by airspeed and attitude sensors. The purpose of this paper is to contribute to the extensive research of destructive vibrations on flexible wing aircraft. The estimation of the wind velocity will be implemented as part of the control design project. This paper is based on literature review of the estimation of wind velocity using only kinematic relationships with a Kalman Filter. The testbed used for wind estimation was a Volantex Ranger EX 757-3. Experimental data of velocity, altitude, and attitude were obtained by performing circular maneuvers at Daytona Beach Radio Control Association. After sampling and processing all the data, the computer code returns the wind velocity estimation of a North-East-Down frame and the airspeed sensor calibration factor. Results show a valid estimation when compared with the local weather data of the date of flight and the sensor calibration factor within typical range. This method of wind velocity estimation is proven to be valid and will yield to the estimation of the incident angles using aerodynamic forces relationships

Noninvasive electrocardiographic imaging of dynamic atrioventricular delay programming in a patient with left bundle branch block

Introduction The response to cardiac resynchronization therapy (CRT) is determined by various factors, including left ventricular (LV) lead location, atrioventricular (AV) delay, and inter-/intraventricular delays. Advances in quadripolar lead technology and device algorithms have improved patient response, yet selection of optimal settings remains challenging. Studies have shown acute improvement in electrical synchrony with manual AV optimization by fusion optimized intervals1,2; automated device algorithms, for example AdaptivCRT (Medtronic, Minneapolis, MN),3 SmartDelay (Boston Scientific, Marlborough, MA),4 and SyncAVTM (Abbott, Sylmar, CA)5; and pacing from multiple LV lead electrodes with MultiPoint Pacing (MPP).6,7 The aim of this clinical case report was to evaluate the acute benefits of SyncAV Plus in the new-generation, Bluetooth-enabled GallantTM CRT device (Abbott, Sylmar, CA). SyncAV Plus continually programs the paced AV delay shorter than the intrinsic PR interval by a programmable offset (% of PR duration) to synchronize intrinsic and ventricular paced activation wavefronts. Twelve-lead electrocardiogram (ECG) and noninvasive electrocardiographic imaging (ECGi) epicardial mapping analyses were performed to characterize the impact of SyncAV Plus on electrical synchrony during a range of CRT programming strategies, including biventricular (BiV) pacing, MPP, LV-only pacing, and LV-only pacing with MPP

A Socio-Ecological Assessment of the Potential for Vegetable Gardens in Elementary Schools Across an Urban Tropical Watershed in Puerto Rico

School vegetable gardens provide environmental services and social benefits that can have a wide impact in communities and cities, while preparing future generations for more sustainable ways of living. For a school to create and sustain a vegetable garden, both social and physical environment (soils) must be favorable. We evaluated 20 elementary schools in the Rio Piedras watershed of San Juan, Puerto Rico. At these schools, we surveyed school principals to identify social factors that are considered opportunities and constraints to establishing and sustaining a school garden. We also described the physical and chemical properties of the soils from the most suitable locations for vegetable gardens in the schoolyards. For social factors, some schools had discontinued gardening because of dwindling funding, waning interest of teachers and parents. Through in-person interviews, principals identified factors that help in implementing and sustaining long-term vegetable gardens: engagement of stakeholders, sponsorship, gardening skills and logistics, and curriculum integration. For ecological factors, the destruction of crops by exotic iguanas was also a reason that stopped school garden activities in some cases. Generally, school soils were highly disturbed, with high bulk density and low nutrient availability. The soils will require considerable remediation and management to sustain vegetable gardens in Rio Piedras schools. A social-ecological approach like that used here could be used to evaluate school gardens at other jurisdictions to increase the likelihood of success of gardening activities

Long term conservation of electrical synchrony by multipoint pacing with dynamic atrioventricular delays

Introduction Automatic adjustment of atrioventricular delay (AVD) with SyncAV has been shown to improve electrical synchronization. However, the long term effects of SyncAV optimization on electrical synchrony are unknown. Purpose Evaluate the effect of SyncAV programming on 6-month (6mo) QRS duration during biventricular (BiV) and left ventricle only MultiPoint Pacing (MPP). Methods Patients with LBBB and QRS duration (QRSd) ≥ 150 ms scheduled for CRT-P/D device implantation with quadripolar LV lead were enrolled in this prospective study. QRSd was measured post-implant from 12-lead surface ECG by blinded experts during the following pacing modes: intrinsic conduction, MPP (MPP=RV+LV1+LV2) and LV-only MPP (LVMPP=LV1+LV2). For each mode, SyncAV was enabled (e.g. MPP+SyncAV) with the patient-tailored SyncAV offset that minimized QRSd. Patients were then randomized 1:1 to receive MPP+SyncAV or LVMPP+SyncAV with the optimal offset identified at implant, and QRSd was re-evaluated at the 6mo follow-up. Results Fifty-nine patients (72% male, 41% ischemic, 26% ejection fraction, 166 ms intrinsic QRSd) completed device implant and QRSd assessment. Relative to intrinsic conduction at implant, the MPP+SyncAV group (n=30) had a QRSd reduction of 26% at implant (162 to 122 ms, p<0.001), and 20% at 6mo (162 to 130 ms, p<0.001). The LVMPP+SyncAV group (n=29) had a QRSd reduction of 24% at implant (165 to 128 ms, p<0.001), and 15% at 6mo (165 to 140 ms, p<0.001). In the MPP+SyncAV group, 28/30 (93%) of patients had more than 10% reduction in QRSd with respect to intrinsic at implant, with 27/30 (90%) maintaining this trend at 6 mo follow up. With LVMPP+SyncAV pacing, only 25/29 (86%) of patients had more than 10% reduction in QRSd with respect to intrinsic at implant, and this reduced to 18/29 (62%) maintaining this trend at 6 mo follow up. Conclusion MPP combined with SyncAV significantly improved acute electrical synchrony at implant in CRT patients with LBBB, as assessed by QRSd reduction. Significant QRSd reduction was maintained at 6 months post-implant by both biventricular and LV-only MPP configurations

Describing the highly 3D flow in the right ventricle

Visualization of the three-dimensional flow within the Right Ventricle (RV) is a challenging issue due to the fully three-dimensional geometry of the ventricular cavity. To date proper characterization and quantification of the RV flow still remains incomplete, and techniques that can be easily applied to current medical imaging are scarce. A method for simulating the highly complex, multi directional flow within the RV is presented by coupling 4D echocardiography imaging with numerical simulations based on the Immersed Boundaries Method (IBM). A novel formulation for accurately computing the space-time distribution of the blood residence time inside the cavity is introduced. Results showed an initial compact vortex forming past the tricuspid orifice at early diastole that quickly breaks into a weakly turbulent flow pattern and rearranges, during systole, into a peculiar stream-wise vortex spinning out towards the pulmonary orifice. This arrangement is maintained when the Ejection Fraction (EF) is reduced from 58 to 32%. The average blood transit time is found to scale almost inversely proportional to the EF. A careful analysis of the residence time permitted to assess the relative significance of the different flow components (from the direct flow, with a residence time less than one heartbeat, to the residual volume, that stagnates in the ventricle) and their distribution in space

Acoustic emission monitoring for assessment of prestressed concrete beams

Acoustic emission (AE) was used to monitor eight prestressed concrete (PC) T-shaped beams that were tested per the ACI 437 cyclic load test (CLT) method. Limited research has examined the validity of this test method for PC structures. The study aims to explore the use of AE for damage evaluation as a supplement to conventional measurements used to assess the condition of a structure based on the CLT acceptance criteria. The beams had different initial conditions: five specimens were pre-cracked and corroded to different corrosion levels while the remaining unconditioned beams served as control specimens. AE enabled to monitor the accumulation of damage during the load tests and damage quantification charts based on AE data are presented. These charts allowed determining load test failure with better sensitivity than the existing ACI 437 evaluation criteria. The charts enabled the assessment of damage regardless of the specimens’ initial condition. In addition, it is shown that accurate damage source location and crack mapping can be achieved by using suitably filtered AE data