Light field super resolution through controlled micro-shifts of light field sensor

Light field cameras enable new capabilities, such as post-capture refocusing and aperture control, through capturing directional and spatial distribution of light rays in space. Micro-lens array based light field camera design is often preferred due to its light transmission efficiency, cost-effectiveness and compactness. One drawback of the micro-lens array based light field cameras is low spatial resolution due to the fact that a single sensor is shared to capture both spatial and angular information. To address the low spatial resolution issue, we present a light field imaging approach, where multiple light fields are captured and fused to improve the spatial resolution. For each capture, the light field sensor is shifted by a pre-determined fraction of a micro-lens size using an XY translation stage for optimal performance

Recommendations for a smart toy parental control tool

Current smart toy parental control tools offered by toy companies do not adequately support parents in protecting their children. Moreover, there is no reference solution in the literature to be used by toymakers. Most studies are limited to mentioning the importance and purpose of these tools or some specific requirements. This article proposes a reference solution for smart toy parental control tools, with which parents can take control and adequately manage their children’s data according to their preferences. This reference solution comprises a recommended list of requirements, a conceptual model, and a prototype developed as a proof of concept for the solution. An analysis highlights that current legal standards for privacy protection do not satisfy the requirements raised in this study. Furthermore, the results of an evaluation conducted with experts show that the proposed solution is adequate to be used as a reference by academia and industry

Evaluation of aircraft auxiliary power unit near-field acoustics for condition monitoring

This paper presents a comprehensive evaluation of the near-field acoustics of an aircraft auxiliary power unit (APU), based on experimental data acquired from an in-situ APU. The aim is to establish whether near-field acoustics can be implemented for online condition monitoring. The APU of Cranfield University’s demonstrator aircraft, a Boeing 737-400, has been instrumented to acquire acoustics (near-field and far-field) and vibration data in synchronization with aircraft state parameters under a wide range of operating conditions. The acquired data is first implemented to determine the efficacy of employing near-field / far-field microphones, and vibration sensors, to monitor the combustion noise and tonal frequency levels from the APU components. Subsequently, an evaluation of the broadband characteristics of the vibroacoustic data and its variations against APU states and performance parameters is conducted based on several categories of feature extraction techniques. The findings suggest that nearfield acoustics lacks the ability to capture the combustion noise process. In addition, the tonal frequencies are also lost due to the level of background noise, fluctuations in the APU speeds, and scattering effects. For the same reasons, the phase couplings occurring between the signals generated by the APU components cannot be detected using acoustic data. Nevertheless, the overall analysis substantiates that the near-field acoustic data can be used to predict the APU operating states and has the potential to be implemented for developing APU performance parameter estimation models to enable condition monitoring

Thermal conductivity performance in sodium alginate-based Casson nanofluid flow by a curved Riga surface

This study examines the effects of a porous media and thermal radiation on Casson-based nano liquid movement over a curved extending surface. The governing equations are simplified into a system of ODEs (ordinary differential equations) using the appropriate similarity variables. The numerical outcomes are obtained using the shooting method and Runge-Kutta Fehlbergs fourth-fifth order (RKF-45). An analysis is conducted to discuss the impact of significant nondimensional constraints on the thermal and velocity profiles. The findings show that the rise in curvature constraint will improve the velocity but diminish the temperature. The increased values of the modified Hartmann number raise the velocity, but a reverse trend is seen for increased porosity parameter values. Thermal radiation raises the temperature, while modified Hartmann numbers and the Casson factor lower the velocity but raise the thermal profile. Moreover, the existence of porous and solid fractions minimizes the surface drag force, and radiation and solid fraction components enhance the rate of thermal dispersion. The findings of this research may have potential applications in the design of heat exchangers used in cooling electronic devices like CPUs and GPUs, as well as microscale engines such as microturbines and micro-heat engines

Development of a far-field noise estimation model for an aircraft auxiliary power unit

Aircraft Auxiliary Power Unit (APU) is one of the major aircraft systems and is reported to be a key driver of unscheduled maintenance. So far, the research has been focused on the implementation of the APU thermodynamic state data to isolate and diagnose faults. To advance the available diagnostic techniques, research work has been initiated to explore the potential of employing far-field microphone data for the identification and isolation of APU faults. This paper aims to address the first step required in the overall effort and proposes a novel methodology for the development of a noise model that can be used for evaluating noise as a source of fault diagnostics. The methodology integrates experimentally acquired full-scale aircraft state and noise data, a physics-based APU thermodynamic model, and semi-empirical noise models to estimate the noise produced by an aircraft APU based on a limited parameter-set. The methodology leads to a model which works by estimating the unknown thermodynamic parameters from the limited dataset and then passes on the relevant parameters to noise estimation models (combustion/jet noise models). An inherent part of the model is the effect of multipath propagation and ground reflections for which a relationship has been analytically derived that considers all the necessary parameters. The developed model has been validated against experimental noise and thermodynamic data acquired from a Boeing 737-400 aircraft APU under several different operating conditions. The acquired noise estimates suggest that the proposed approach provides an accurate estimation of the far-field noise under a wide range of APU operating conditions, both at the sub-system and APU level. The model would act as an enabler to simulate APU noise data under degraded functional states and subsequently developing fault diagnostic schemes based on the far-field noise data

Technique and Role of Embolization using Ethylene Vinyl-Alcohol Copolymer before Carotid Body Tumor Resection.

A 45-year old female referred for a large carotid body tumor resection. The tumor was encasing the internal (ICA) and external carotid arteries (ECA). She underwent angiogram and embolization of the ascending pharyngeal artery and a distal branch of the ECA using ethylene vinyl-alcohol copolymer (EVOH). Two days later, surgical resection of the tumor with regional lymph node dissection was performed along with an interposition reversed vein graft anastomosis between the mid common carotid and distal ICA. Devascularization of carotid body tumor can be performed using EVOH delivered through trans-arterial and percutaneous routes. Embolization may facilitate surgical resection and decrease blood loss but does not decrease the rate of neurological complications. Embolization can be performed by the vascular surgeon before a large carotid body tumor resection with minimal migration and or stroke risk

Standalone and RTK GNSS on 30,000 km of North American Highways

There is a growing need for vehicle positioning information to support Advanced Driver Assistance Systems (ADAS), Connectivity (V2X), and Automated Driving (AD) features. These range from a need for road determination (<5 meters), lane determination (<1.5 meters), and determining where the vehicle is within the lane (<0.3 meters). This work examines the performance of Global Navigation Satellite Systems (GNSS) on 30,000 km of North American highways to better understand the automotive positioning needs it meets today and what might be possible in the near future with wide area GNSS correction services and multi-frequency receivers. This includes data from a representative automotive production GNSS used primarily for turn-by-turn navigation as well as an Inertial Navigation System which couples two survey grade GNSS receivers with a tactical grade Inertial Measurement Unit (IMU) to act as ground truth. The latter utilized networked Real-Time Kinematic (RTK) GNSS corrections delivered over a cellular modem in real-time. We assess on-road GNSS accuracy, availability, and continuity. Availability and continuity are broken down in terms of satellite visibility, satellite geometry, position type (RTK fixed, RTK float, or standard positioning), and RTK correction latency over the network. Results show that current automotive solutions are best suited to meet road determination requirements at 98% availability but are less suitable for lane determination at 57%. Multi-frequency receivers with RTK corrections were found more capable with road determination at 99.5%, lane determination at 98%, and highway-level lane departure protection at 91%.Comment: Accepted for the 32nd International Technical Meeting of the Satellite Division of The Institute of Navigation (ION GNSS+ 2019), Miami, Florida, September 201

Material Food Probes:Personalized 3D Printed Flavors for Intimate Communication

Interactions with food are complex, integrating rich multisensory experiences within emotionally meaningful social contexts. Yet, the opportunities to explore food as material resource for emotional communication have been less explored. We describe a two-month project with 5 couples centered on the co-design of personalized flavors for intimate communication, which were experienced through an explorative three day study involving a 3D food printer in participants’ homes. We discuss the value of our findings indicating preferences for both remembered and imagined positive flavors and their integration in focal intimacy practices to support emotional coregulation. We also discuss material food probes and their value for exploring and inspiring both design-with and design-around food