scholarly journals On-Body Characterization of Planar Differential Antennas for Multiple, Wide, and Narrow Bands

2016 ◽  
Vol 2016 ◽  
pp. 1-9
Author(s):  
Luigi Vallozzi ◽  
Domenico Pepe ◽  
Thijs Castel ◽  
Hendrik Rogier ◽  
Domenico Zito
Keyword(s):  
Human Body ◽  
Ad Hoc ◽  
Low Cost ◽  
Experimental Tests ◽  
Body Measurements ◽  
Antenna Performance ◽  
Sensing Applications ◽  
The Impact ◽  
Narrow Bands

This paper reports the results of the on-body experimental tests of a set of four planar differential antennas, originated by design variations of radiating elements with the same shape and characterized by the potential for covering wide and narrow bands. All the antenna designs have been implemented on low-cost FR4 substrate and characterized experimentally through on-body measurements. The results show the impact of the proximity to the human body on antenna performance and the opportunities in terms of potential coverage of wide and narrow bands for future ad hoc designs and implementations through wearable substrates targeting on-body and off-body communication and sensing applications.

Computer simulation study about the dependence of amorphous silicon photonic waveguides efficiency on the material quality

2020 ◽  
Vol 90 (3) ◽  
pp. 30502
Author(s):  
Alessandro Fantoni ◽  
João Costa ◽  
Paulo Lourenço ◽  
Manuela Vieira
Keyword(s):  
Amorphous Silicon ◽  
High Throughput Screening ◽  
Simulation Analysis ◽  
Low Cost ◽  
Deposition Process ◽  
Large Area ◽  
Sidewall Roughness ◽  
Sensing Applications ◽  
Fabrication Defects ◽  
The Impact

Amorphous silicon PECVD photonic integrated devices are promising candidates for low cost sensing applications. This manuscript reports a simulation analysis about the impact on the overall efficiency caused by the lithography imperfections in the deposition process. The tolerance to the fabrication defects of a photonic sensor based on surface plasmonic resonance is analysed. The simulations are performed with FDTD and BPM algorithms. The device is a plasmonic interferometer composed by an a-Si:H waveguide covered by a thin gold layer. The sensing analysis is performed by equally splitting the input light into two arms, allowing the sensor to be calibrated by its reference arm. Two different 1 × 2 power splitter configurations are presented: a directional coupler and a multimode interference splitter. The waveguide sidewall roughness is considered as the major negative effect caused by deposition imperfections. The simulation results show that plasmonic effects can be excited in the interferometric waveguide structure, allowing a sensing device with enough sensitivity to support the functioning of a bio sensor for high throughput screening. In addition, the good tolerance to the waveguide wall roughness, points out the PECVD deposition technique as reliable method for the overall sensor system to be produced in a low-cost system. The large area deposition of photonics structures, allowed by the PECVD method, can be explored to design a multiplexed system for analysis of multiple biomarkers to further increase the tolerance to fabrication defects.

Experimental Investigation and Characterization of the Rotating Stall in a High Pressure Centrifugal Compressor: Part II — Influence of Diffuser Geometry on Stage Performance

2002 ◽  
Author(s):  
G. Ferrara ◽  
L. Ferrari ◽  
C. P. Mengoni ◽  
M. De Lucia ◽  
L. Baldassarre
Keyword(s):  
Experimental Tests ◽  
Rotating Stall ◽  
Geometric Parameters ◽  
Flow Coefficient ◽  
Low Flow ◽  
Main Task ◽  
Stage Performance ◽  
The Impact ◽  
Prediction Criteria

Extensive research on centrifugal compressors has been planned. The main task of the research is to improve present prediction criteria coming from the literature with particular attention to low flow coefficient impellers (low width to radius ratios) where they are no more valid. Very little data has been published for this kind of stages, especially for the last stage configuration (with discharge volute). Many experimental tests have been planned to investigate different configurations. A simulated stage with a backward channel upstream, a 2D impeller with a vaneless diffuser and a constant cross section volute downstream constitute the basic configuration. Several diffuser types with different widths, pinch shapes and diffusion ratios were tested. The effect of geometric parameters on stage stability has been discussed inside part I of the present work; the purpose of this part of the work is to illustrate the effect of the same geometric parameters on stage performance and to quantify the impact of stability improvements on stage losses.

PLA conductive filament for 3D printed smart sensing applications

2018 ◽  
Vol 24 (4) ◽  
pp. 739-743 ◽  
Author(s):  
Simone Luigi Marasso ◽  
Matteo Cocuzza ◽  
Valentina Bertana ◽  
Francesco Perrucci ◽  
Alessio Tommasi ◽  
...  
Keyword(s):  
Temperature Sensor ◽  
Low Cost ◽  
Conductive Polymer ◽  
Temperature Characteristic ◽  
Temperature Sensors ◽  
Electrical Performance ◽  
Content Type ◽  
Sensing Applications ◽  
3D Printed

Purpose This paper aims to present a study on a commercial conductive polylactic acid (PLA) filament and its potential application in a three-dimensional (3D) printed smart cap embedding a resistive temperature sensor made of this material. The final aim of this study is to add a fundamental block to the electrical characterization of printed conductive polymers, which are promising to mimic the electrical performance of metals and semiconductors. The studied PLA filament demonstrates not only to be suitable for a simple 3D printed concept but also to show peculiar characteristics that can be exploited to fabricate freeform low-cost temperature sensors. Design/methodology/approach The first part is focused on the conductive properties of the PLA filament and its temperature dependency. After obtaining a resistance temperature characteristic of this material, the same was used to fabricate a part of a 3D printed smart cap. Findings An approach to the characterization of the 3D printed conductive polymer has been presented. The major results are related to the definition of resistance vs temperature characteristic of the material. This model was then exploited to design a temperature sensor embedded in a 3D printed smart cap. Practical implications This study demonstrates that commercial conductive PLA filaments can be suitable materials for 3D printed low-cost temperature sensors or constitutive parts of a 3D printed smart object. Originality/value The paper clearly demonstrates that a new generation of 3D printed smart objects can already be obtained using low-cost commercial materials.

A Characterization of Cam Transmissions Through an Identification of Lumped Parameters

2006 ◽  
Author(s):  
Giuseppe Carbone ◽  
Chiara Lanni ◽  
Marco Ceccarelli ◽  
Giovanni Incerti ◽  
Monica Tiboni
Keyword(s):  
Dynamic Behaviour ◽  
Low Cost ◽  
Experimental Tests ◽  
Experimental Procedure ◽  
Operation Procedure ◽  
Alternative Testing ◽  
Lumped Parameters ◽  
Main Components ◽  
Easy Operation

In this paper, a numerical-experimental procedure is proposed for an identification of parameters in cam transmissions. Models with lumped parameters are defined specifically for cam transmissions. Experimental tests are carried out on main components of a cam transmission in order to estimate the values of mass, damping and stiffness lumped parameters through a low-cost easy-operation procedure. Experimental tests are also carried out in order to characterize the dynamic behaviour of a whole cam transmission. A comparison of numerical and experimental results is used in order to calibrate the values of lumped parameters. Experimental tests have been carried out by means of suitable test-beds for cams that have been built specifically at University of Brescia and at LARM in Cassino as alternative testing solutions.

scholarly journals High-throughput patterning of photonic structures with tunable periodicity

2015 ◽  
Vol 112 (17) ◽  
pp. 5309-5313 ◽  
Author(s):  
Thomas J. Kempa ◽  
D. Kwabena Bediako ◽  
Sun-Kyung Kim ◽  
Hong-Gyu Park ◽  
Daniel G. Nocera
Keyword(s):  
Cyclic Voltammetry ◽  
High Throughput ◽  
Low Cost ◽  
Optical Elements ◽  
Periodic Arrays ◽  
Sensing Applications ◽  
Scan Rate ◽  
Reactive Interface

A patterning method termed “RIPPLE” (reactive interface patterning promoted by lithographic electrochemistry) is applied to the fabrication of arrays of dielectric and metallic optical elements. This method uses cyclic voltammetry to impart patterns onto the working electrode of a standard three-electrode electrochemical setup. Using this technique and a template stripping process, periodic arrays of Ag circular Bragg gratings are patterned in a high-throughput fashion over large substrate areas. By varying the scan rate of the cyclically applied voltage ramps, the periodicity of the gratings can be tuned in situ over micrometer and submicrometer length scales. Characterization of the periodic arrays of periodic gratings identified point-like and annular scattering modes at different planes above the structured surface. Facile, reliable, and rapid patterning techniques like RIPPLE may enable the high-throughput and low-cost fabrication of photonic elements and metasurfaces for energy conversion and sensing applications.

scholarly journals Performance Evaluation of Alternative Relative Orientation Procedures for UAV-based Imagery with Prior Flight Trajectory Information

2016 ◽  
Vol XLI-B3 ◽  
pp. 21-25 ◽  
Author(s):  
F. He ◽  
A. Habib
Keyword(s):  
Low Cost ◽  
Closed Form Solution ◽  
Experimental Tests ◽  
Form Solution ◽  
Relative Orientation ◽  
Conjugate Points ◽  
Flying Height ◽  
Reliable Estimate ◽  
Comparative Performance ◽  
The Impact

Thanks to recent advances at the hardware (e.g., emergence of reliable platforms at low cost) and software (e.g., automated identification of conjugate points in overlapping images) levels, UAV-based 3D reconstruction has been widely used in various applications. However, mitigating the impact of outliers in automatically matched points in UAV imagery, especially when dealing with scenes that has poor and/or repetitive texture, remains to be a challenging task. In spite of the fact that existing literature has already demonstrated that incorporating prior motion information can play an important role in increasing the reliability of the matching process, there is a lack of methodologies that are mainly suited for UAV imagery. Assuming the availability of prior information regarding the trajectory of a UAV-platform, this paper presents a two-point approach for reliable estimation of Relative Orientation Parameters (ROPs) of UAV-based images. This approach is based on the assumption that the UAV platform is moving at a constant flying height while maintaining the camera in a nadir-looking orientation. For this flight scenario, a closed-form solution that can be derived using a minimum of two pairs of conjugate points is established. In order to evaluate the performance of the proposed approach, experimental tests using real stereo-pairs acquired from different UAV platforms have been conducted. The derived results from the comparative performance analysis against the Nistér five-point approach demonstrate that the proposed two-point approach is capable of providing reliable estimate of the ROPs from UAV-based imagery in the presence of poor and/or repetitive texture with high percentage of matching outliers.

Surgical team: improving teamwork, a review

2019 ◽  
Vol 95 (1124) ◽  
pp. 334-339 ◽  
Author(s):  
Hemant Kumar ◽  
Raimand Morad ◽  
Manish Sonsati
Keyword(s):  
Ad Hoc ◽  
Current System ◽  
Low Cost ◽  
High Yield ◽  
Surgical Team ◽  
Team Members ◽  
Surgical Teams ◽  
The Impact ◽  
Team Familiarity ◽  
Simulated Training

Teams within surgery have been through countless cycles of refinement with an ever-increasing list of surgical team members. This results in a more dispersed team, making effective teamwork harder to achieve. Furthermore, the ad hoc nature of surgical teams means that team familiarity is not always given. The impact of this is seen across the field, with inadequacies leading to disastrous outcomes. This is a review of research that has been done into the topic of surgical teams. It will investigate barriers and consider the evidence available on how to improve the current system. Studies show an increased effectiveness of surgical teams with structures that allowed consistency in team members. The research advocates that advancements made in improving teamwork and efficiency can prove to be a low-cost but high-yield strategy for development. This can be in terms of simulated training, staff turnover management and fixed team allocation.

scholarly journals Slotted ALOHA on LoRaWAN-Design, Analysis, and Deployment

Sensors ◽  
2019 ◽  
Vol 19 (4) ◽  
pp. 838 ◽  
Author(s):  
Tommaso Polonelli ◽  
Davide Brunelli ◽  
Achille Marzocchi ◽  
Luca Benini
Keyword(s):  
Single Channel ◽  
Low Cost ◽  
Network Throughput ◽  
Sensor Nodes ◽  
Slotted Aloha ◽  
Medium Access ◽  
Packet Collision ◽  
Sensing Applications ◽  
Hardware Platforms ◽  
The Impact

LoRaWAN is one of the most promising standards for long-range sensing applications. However, the high number of end devices expected in at-scale deployment, combined with the absence of an effective synchronization scheme, challenge the scalability of this standard. In this paper, we present an approach to increase network throughput through a Slotted-ALOHA overlay on LoRaWAN networks. To increase the single channel capacity, we propose to regulate the communication of LoRaWAN networks using a Slotted-ALOHA variant on the top of the Pure-ALOHA approach used by the standard; thus, no modification in pre-existing libraries is necessary. Our method is based on an innovative synchronization service that is suitable for low-cost wireless sensor nodes. We modelled the LoRaWAN channel with extensive measurement on hardware platforms, and we quantified the impact of tuning parameters on physical and medium access control layers, as well as the packet collision rate. Results show that Slotted-ALOHA supported by our synchronization service significantly improves the performance of traditional LoRaWAN networks regarding packet loss rate and network throughput.

scholarly journals Performance Evaluation of Alternative Relative Orientation Procedures for UAV-based Imagery with Prior Flight Trajectory Information

2016 ◽  
Vol XLI-B3 ◽  
pp. 21-25
Author(s):  
F. He ◽  
A. Habib
Keyword(s):  
Low Cost ◽  
Closed Form Solution ◽  
Experimental Tests ◽  
Form Solution ◽  
Relative Orientation ◽  
Conjugate Points ◽  
Flying Height ◽  
Reliable Estimate ◽  
Comparative Performance ◽  
The Impact

Thanks to recent advances at the hardware (e.g., emergence of reliable platforms at low cost) and software (e.g., automated identification of conjugate points in overlapping images) levels, UAV-based 3D reconstruction has been widely used in various applications. However, mitigating the impact of outliers in automatically matched points in UAV imagery, especially when dealing with scenes that has poor and/or repetitive texture, remains to be a challenging task. In spite of the fact that existing literature has already demonstrated that incorporating prior motion information can play an important role in increasing the reliability of the matching process, there is a lack of methodologies that are mainly suited for UAV imagery. Assuming the availability of prior information regarding the trajectory of a UAV-platform, this paper presents a two-point approach for reliable estimation of Relative Orientation Parameters (ROPs) of UAV-based images. This approach is based on the assumption that the UAV platform is moving at a constant flying height while maintaining the camera in a nadir-looking orientation. For this flight scenario, a closed-form solution that can be derived using a minimum of two pairs of conjugate points is established. In order to evaluate the performance of the proposed approach, experimental tests using real stereo-pairs acquired from different UAV platforms have been conducted. The derived results from the comparative performance analysis against the Nistér five-point approach demonstrate that the proposed two-point approach is capable of providing reliable estimate of the ROPs from UAV-based imagery in the presence of poor and/or repetitive texture with high percentage of matching outliers.

scholarly journals COMPARISON BETWEEN RGB AND RGB-D CAMERAS FOR SUPPORTING LOW-COST GNSS URBAN NAVIGATION

2018 ◽  
Vol XLII-2 ◽  
pp. 991-998 ◽  
Author(s):  
L. Rossi ◽  
C. I. De Gaetani ◽  
D. Pagliari ◽  
E. Realini ◽  
M. Reguzzoni ◽  
...  
Keyword(s):  
Kalman Filter ◽  
Extended Kalman Filter ◽  
Urban Areas ◽  
Ad Hoc ◽  
Focal Length ◽  
Low Cost ◽  
Experimental Tests ◽  
Microsoft Kinect ◽  
Visual Data ◽  
Data Accessibility

A pure GNSS navigation is often unreliable in urban areas because of the presence of obstructions, thus preventing a correct reception of the satellite signal. The bridging between GNSS outages, as well as the vehicle attitude reconstruction, can be recovered by using complementary information, such as visual data acquired by RGB-D or RGB cameras. In this work, the possibility of integrating low-cost GNSS and visual data by means of an extended Kalman filter has been investigated. The focus is on the comparison between the use of RGB-D or RGB cameras. In particular, a Microsoft Kinect device (second generation) and a mirrorless Canon EOS M RGB camera have been compared. The former is an interesting RGB-D camera because of its low-cost, easiness of use and raw data accessibility. The latter has been selected for the high-quality of the acquired images and for the possibility of mounting fixed focal length lenses with a lower weight and cost with respect to a reflex camera. The designed extended Kalman filter takes as input the GNSS-only trajectory and the relative orientation between subsequent pairs of images. Depending on the visual data acquisition system, the filter is different because RGB-D cameras acquire both RGB and depth data, allowing to solve the scale problem, which is instead typical of image-only solutions. The two systems and filtering approaches were assessed by ad-hoc experimental tests, showing that the use of a Kinect device for supporting a u-blox low-cost receiver led to a trajectory with a decimeter accuracy, that is 15 % better than the one obtained when using the Canon EOS M camera.

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