Experimental System Prototype of a Portable, Low-Cost, C-Scan Ultrasound Imaging Device

The constructed wetland is a low-cost technology to control environmental pollution. The system is especially suitable for small settlements. An innovative constructed wetland technology is described in this paper. A pilot plant was used to assess the performance of the system. The experimental system consists of two serial connected tanks that settled up with fillers and Cyperus as treatment media. Wastewater is recycled periodically upward and downward between the two tanks. The treatment performance was monitored in different loading conditions in a one-year period. The average COD removal efficiency of 90% was observed at 122 g COD/m2.day average loading conditions. Other average removal values in the same conditions are as follows: suspended solid 95%, TKN 77%, total nitrogen 61%, PO4-P 39%. The land requirement for this system will be 0.82 m2 per capita when applying as full-scale system.

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A 40 Mb/s VLC System Reusing an Existing Large LED Panel in an Indoor Office Environment

Sensors ◽

10.3390/s21051697 ◽

2021 ◽

Vol 21 (5) ◽

pp. 1697

Author(s):

Xicong Li ◽

Zabih Ghassemlooy ◽

Stanislav Zvánovec ◽

Paul Anthony Haigh

Keyword(s):

Modulation Depth ◽

Light Emitting Diode ◽

Low Cost ◽

Data Communication ◽

Experimental System ◽

Digital Signal ◽

Visible Light Communication ◽

Cost Driver ◽

Limiting Factors ◽

Light Sources

With advances in solid-state lighting, visible light communication (VLC) has emerged as a promising technology to enhance existing light-emitting diode (LED)-based lighting infrastructure by adding data communication capabilities to the illumination functionality. The last decade has witnessed the evolution of the VLC concept through global standardisation and product launches. Deploying VLC systems typically requires replacing existing light sources with new luminaires that are equipped with data communication functionality. To save the investment, it is clearly desirable to make the most of the existing illumination systems. This paper investigates the feasibility of adding data communication functionality to the existing lighting infrastructure. We do this by designing an experimental system in an indoor environment based on an off-the-shelf LED panel typically used in office environments, with the dimensions of 60 × 60 cm2. With minor modifications, the VLC function is implemented, and all of the modules of the LED panel are fully reused. A data rate of 40 Mb/s is supported at a distance of up to 2 m while using the multi-band carrierless amplitude and phase (CAP) modulation. Two main limiting factors for achieving higher data rates are observed. The first factor is the limited bandwidth of the LED string inside the panel. The second is the flicker due to the residual ripple of the bias current that is generated by the panel’s driver. Flicker is introduced by the low-cost driver, which provides bias currents that fluctuate in the low frequency range (less than several kilohertz). This significantly reduces the transmitter’s modulation depth. Concurrently, the driver can also introduce an effect that is similar to baseline wander at the receiver if the flicker is not completely filtered out. We also proposed a solution based on digital signal processing (DSP) to mitigate the flicker issue at the receiver side and its effectiveness has been confirmed.

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A Fast Calibration and Compensation Method for Magnetometers in Strap-Down Spinning Projectiles

Sensors ◽

10.3390/s18124157 ◽

2018 ◽

Vol 18 (12) ◽

pp. 4157 ◽

Cited By ~ 4

Author(s):

Dafeng Long ◽

Xiaoming Zhang ◽

Xiaohui Wei ◽

Zhongliang Luo ◽

Jianzhong Cao

Keyword(s):

Low Cost ◽

Experimental System ◽

Calibration Method ◽

Attitude Estimation ◽

Attitude Measurement ◽

Angle Error ◽

Estimation Errors ◽

Zero Bias ◽

Launch Site ◽

Spinning Projectile

Attitude measurement is an essential technology in projectile trajectory correction. Magnetometers have been used for projectile attitude measurement systems as they are small in size, lightweight, and low cost. However, magnetometers are seriously disturbed by the artillery magnetic field during launch. Moreover, the error parameters of the magnetometers, which are calibrated in advance, usually change after extended storage. The changed parameters have negative effects on attitude estimation of the projectile. To improve the accuracy of attitude estimation, the magnetometers should be calibrated again before launch or during flight. This paper presents a fast calibration method specific for a spinning projectile. At the launch site, the tri-axial magnetometer is calibrated, the parameters of magnetometer are quickly obtained by optimal ellipsoid fitting based on a least squares criterion. Then, the calibration parameters are used to compensate for magnetometer outputs during flight. The numerical simulation results show that the proposed calibration method can effectively determine zero bias, scale factors, and alignment angle errors. Finally, a semi-physical experimental system was designed to further verify the performance of the calibration method. The results show that pitch angle error reduces from 3.52° to 0.58° after calibration. The roll angle error is reduced from 2.59° to 0.65°. Simulations and experimental results indicate that the accuracy of magnetometer in strap-down spinning projectile has been greatly enhanced, and the attitude estimation errors are reduced after calibration.

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Ultrasound detection using optical interferometry

10.32920/ryerson.14651565 ◽

2021 ◽

Author(s):

Nusrat Jahan Surovy

Keyword(s):

Thin Film ◽

Ultrasound Imaging ◽

Detection System ◽

Incidence Angle ◽

Low Cost ◽

3D Ultrasound ◽

Attractive Alternative ◽

Simulation Results ◽

Exerted Pressure ◽

Piezoelectric Devices

Ultrasound imaging is a widely used noninvasive imaging technique for biomedical and other applications. Piezoelectric devices are commonly used for the generation and detection of ultrasound in these applications. However, implementation of two-dimensional arrays of piezoelectric transducers for 3D ultrasound imaging is complex and expensive. Optical Fabry-Perot interferometry is an attractive alternative to the piezoelectric devices for detection of ultrasound. In this method a thin film etalon is constructed and used. Light reflected from the two surfaces of this thin film produces an intensity which depends on the film thickness. When ultrasound is incident on the film, it changes the thickness of the film and consequently modulates the light intensity on the film. In our work, we made two types of etalon (Finesse 2) for our experiment. We detected lower frequency ultrasound (0.5 MHz or 1 MHz) using the build etalon. We determined a linear relationship between the strength of the optical signals and the exerted pressure on a film by the ultrasound. The dependence of the etalon performance on the light wavelength was demonstrated indirectly by measuring the signal at various light incidence angle. Simulation results are also presented. Lastly, we proposed the optimum design of this detection system based on the simulation results. This method of ultrasound detection can be a potential low-cost approach for 3D ultrasound imaging.

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1MW-Class Solid Oxide Electrolyser System Prototype for Low-Cost Green Hydrogen

ECS Transactions ◽

10.1149/10301.0383ecst ◽

2021 ◽

Vol 103 (1) ◽

pp. 383-392

Author(s):

Jonathan Harman ◽

Per Hjalmarsson ◽

Joshua Mermelstein ◽

Joshua Ryley ◽

Harry Sadler ◽

...

Keyword(s):

Low Cost ◽

Solid Oxide ◽

System Prototype

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Biogenic Gas Vesicles for Ultrasound Imaging and Targeted Therapeutics

Current Medicinal Chemistry ◽

10.2174/0929867328666210705145642 ◽

2021 ◽

Vol 28 ◽

Author(s):

Rui Wang ◽

Li Zhang ◽

Mingxing Xie ◽

Lufang Wang ◽

Qiaofeng Jin ◽

...

Keyword(s):

Ultrasound Imaging ◽

Low Cost ◽

Cell Metabolism ◽

Drug Carriers ◽

Ultrasound Contrast Agents ◽

Targeted Therapeutics ◽

Gas Vesicles ◽

Biogenic Gas ◽

Delivery Technique ◽

Imaging Mode

: Ultrasound is not only the most widely used medical imaging mode for diagnostics owing to its real-time, non-radiation, portable, and low-cost merits, but also a promising targeted drug/gene delivery technique by exhibiting a series of powerful bioeffects. The development of micron-sized or nanometer-sized ultrasound agents or delivery carriers further makes ultrasound a distinctive modality in accurate diagnosis and effective treatment. In this review, we introduce one kind of unique biogenic gas-filled protein nanostructures called gas vesicles, presenting some unique characteristics than the conventional microbubbles. Gas vesicles can not only serve as ultrasound contrast agents with innovative imaging methods such as cross-amplitude modulation harmonic imaging but also can further be adjusted and optimized via genetic engineering techniques. Moreover, they could not only serve as acoustic gene reporters, acoustic biosensors to monitor the cell metabolism, but also serve as cavitation nuclei and drug carriers for therapeutic purposes. In this study, we focus on the latest development and applications in the area of ultrasound imaging and targeted therapeutics, and also provide a brief introduction of the corresponding mechanisms. In summary, these biogenic gas vesicles show some advantages over conventional MBs that deserve more efforts to promote their development.

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On the suitability of induction heating system for metal additive manufacturing

Proceedings of the Institution of Mechanical Engineers Part B Journal of Engineering Manufacture ◽

10.1177/0954405420937854 ◽

2020 ◽

Vol 235 (1-2) ◽

pp. 219-229 ◽

Cited By ~ 1

Author(s):

Gourav K Sharma ◽

Piyush Pant ◽

Prashant K Jain ◽

Pavan K Kankar ◽

Puneet Tandon

Keyword(s):

Energy Source ◽

Additive Manufacturing ◽

Induction Heating ◽

Low Cost ◽

Three Dimensional ◽

Experimental System ◽

Heating System ◽

Industrial Applications ◽

Metallic Materials ◽

Semi Solid

Induction heating is a non-contact-based energy source that has the potential to quickly melt the metal and become the alternate energy source that can be used for additive manufacturing. At present, induction heating is widely used in various industrial applications such as melting, preheating, heat treatment, welding, and brazing. The potential of this source has not been explored in the additive manufacturing domain. However, the use of induction heating in additive manufacturing could lead to low-cost part fabrication as compared to other energy sources such as laser or electron beam. Therefore, this study explores the feasibility of this energy source in additive manufacturing for fabricating parts of metallic materials. An experimental system has been developed by modifying an existing delta three-dimensional printer. An induction heater coil has been incorporated to extruder head for semi-solid processing of the metal alloy. In order to test the viability of the developed system, aluminium material in the filament form has been processed. Obtained results have shown that the induction heating–based energy source is capable of processing metallic materials having a melting point up to 1000° C. The continuous extrusion of the material has been achieved by controlling the extruder temperature using a proportional integral derivative–based controller and k-type thermocouple. The study also discusses various issues and challenges that occurred during the melting of metal with induction heating. The outcomes of this study may be a breakthrough in the area of metal-based additive manufacturing.

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