Application Of Sensor System Research Articles

Construction, Application and Verification of a Novel Formaldehyde Gas Sensor System Based on Ni-Doped SnO2 Nanoparticles

An efficient formaldehyde (HCHO) gas sensor system based on nickel-doped tin oxide (Ni-doped SnO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> ) nanoparticle sensor and back-end circuit has been developed. Ni-doped SnO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> nanoparticles are prepared by a simple one-step hydrothermal method. To complete the function of detecting HCHO gas in real time, a back-end circuit suitable for resistance measurement of nanoparticle sensors and an organic light emitting diode screen which can display the output of gas concentration data are integrated as a portable device. Compared with the traditional HCHO detection device, this designed system exhibits better stability, excellent selectivity, and high response. Its detection limit is as low as 90 ppb. The gas response to 50 ppm HCHO is 67.63. Further for the quantitative evaluation, we refer to and modify the existing HCHO diffusion model, then carry out a practical test on the HCHO diffusion at the same time. The comparison between the theoretical fitting curve and the actual test curve matched well enough to reflect the potential of this system for the practical HCHO evaluation.

Research Progress on Models, Algorithms, and Systems for Remote Sensing Spatial-Temporal Big Data Processing

With the rapid development of high-resolution earth observation systems, the data processing, algorithm design, and system development of remote sensing spatial-temporal big data (RS-STBD) have gradually become the bottleneck problems in the application and development of earth observation system. The research on the model, algorithm, and system of RS-STBD processing involves complex scientific problems, technical bottlenecks, and inconstant requirements of engineering applications. This article summarizes the data type and processing theory model of RS-STBD, the high-performance algorithm design based on cloud service and intelligent computing, and the architecture design and engineering development methods of the complex remote sensing application system. Furthermore, the existing problems in the current research are analyzed, and the related solutions are given. Finally, the future development trend of scientific exploration, technical research, and application development of RS-STBD has prospected.

Assessment of the Piezoelectric Response of an Epoxy Resin/SbSINanowires Composite Filling FDM Printed Grid.

This paper shows a piezoelectric response from an innovative sensor obtained by casting epoxy-SbSI (antimony sulfoiodide) nanowires nanocomposite to a grid structure printed using a fuse deposition modeling (FDM) method. The grid is shown to be a support structure for the nanocomposite. The applied design approach prospectively enables the formation of sensors with a wide spectrum of shapes and a wide applicability. The voltage signal obtained as a result of the piezoelectric effect reached 1.5V and 0.5V under a maximum static stress of 8.5 MPa and under a maximum dynamic stress of 22.3 kPa, respectively. These values are sufficient for potential application in sensor systems. The effect of a systematic increase in the voltage signal with subsequent cycles was also observed, which similarly allows the use of these sensors in monitoring systems for structures exposed to unfavorable cyclical loads. The obtained results also show that the piezoelectric signal improves with increase in strain rate.

A modified single-polarization THz fiber with epsilon-near-zero (ENZ) material

A highly birefringent square lattice terahertz (THz) photonic crystal fiber (PCF) coated with epsilon-near-zero (ENZ) material and doped with gain material is proposed for single polarization propagation. Due to introduction of the ENZ rings into square lattice, the large loss difference between the x-polarization mode and all other modes is obtained. The loss of the x-polarization mode is compensated by doping the core area with gain material. The single polarization PCF obtains a loss difference better than 13.2 dB/cm in the frequency range of 0.960–1.307 THz (bandwidth of 0.347 THz). This proposed single polarization THz PCF has some potential applications in coherent THz communication or polarimetric fiber sensor systems.

Conversion and Visualization of Remote Sensing Image Data in CAD

In this paper, a process visualization model for remote sensing image classification algorithms is constructed to analyze the current processing characteristics of process visualization in remote sensing application systems. The usability of the model is verified in a remote sensing application system with a remote sensing image classification algorithm based on support vector machines as an example. Given the characteristics of remote sensing applications that require high visualization process and a large amount of data processing, the basic process of an image classification algorithm for remote sensing applications is summarized by analyzing the basic process of existing image classification algorithms in remote sensing applications, taking into account the characteristics of process visualization. Based on the existing process of remote sensing image classification algorithm, a process visualization model is proposed. The model takes a goal-based process acts as the basic elements of the model, provides visualization functions and interfaces for human-computer interaction through a human-computer interaction selector, and uses a template knowledge base to save processing data and realize the description of customized processes. The model has little impact on the efficiency and accuracy of the support vector machine-based remote sensing image classification algorithm during the process of process visualization and customization. Finally, the application of the model to integrate business processing of earth observation can address the problem of process customization visualization for remote sensing applications to some extent.

Genetically encoded thiol redox-sensors in the zebrafish model: lessons for embryonic development and regeneration.

Important roles for reactive oxygen species (ROS) and redox signaling in embryonic development and regenerative processes are increasingly recognized. However, it is difficult to obtain information on spatiotemporal dynamics of ROS production and signaling in vivo. The zebrafish is an excellent model for in vivo bioimaging and possesses a remarkable regenerative capacity upon tissue injury. Here, we review data obtained in this model system with genetically encoded redox-sensors targeting H2O2 and glutathione redox potential. We describe how such observations have prompted insight into regulation and downstream effects of redox alterations during tissue differentiation, morphogenesis and regeneration. We also discuss the properties of the different sensors and their consequences for the interpretation of in vivo imaging results. Finally, we highlight open questions and additional research fields that may benefit from further application of such sensor systems in zebrafish models of development, regeneration and disease.

The improved denoising algorithm of acoustic sensor based on linear optical fiber Sagnac interferometer

Abstract This paper is devoted to the study of an acoustic sensor system based on linear fiber optic Sagnac interferometer. An improved threshold denoising algorithm combined with the wavelet theory is proposed. Furthermore, a hybrid scheme based on the improved algorithm with bandpass filter is explored, and experimental verification of theoretical investigation is accomplished as well. Taking the measured speech signals as examples, the Allan variance of the signals can be reduced, while the class spacing criterion can be increased. It is of great significance for promoting the application of the fiber optic acoustic sensor system.

Potentiometric Sensor System Based on Modified Thick-Film Electrodes for Determining the Antioxidant Activity of Beverages

Currently, the food industry pays great attention to the research of antioxidants used as food additives and functional food ingredients. Monitoring the antioxidant activity (AOA) of foods containing dietary antioxidants serves as an innovative tool for the food industry development and is an urgent research task. The article presents data on the development, research and application of a single-use potentiometric sensor system based on modified thick-film electrodes made by screen printing to determine the beverages AOA. In the sensor system, the thick-film carbon-containing electrode (TCE) is modified with gold nanoparticles (AuNP), and the thick-film silver-containing electrode (TSE) is modified with a precipitate of silver chloride and ferricyanide (O) and covered with a protective Nafion layer (N). The researchers analyzed the electrochemical and operational characteristics of AuNP/TCE and N/O/TSE. A man found that carbohydrates (glucose, fructose and sucrose) did not affect, and ethyl alcohol affected the potential change in the electrochemical cell and, thus, the amount of antioxidant activity of the drink. The authors provide methodological approach for results correcting of determining the antioxidant activity of alcoholic beverages. The results of AOA beverages determining obtained using commercial electrodes and the developed sensor system are in good agreement (according to the criteria of Fischer and Student).

Fiber Bragg gratings fabricated by femtosecond lasers for narrow-linewidth fiber laser

A narrow-linewidth erbium-doped fiber laser based on the fiber Bragg gratings (FBGs) fabricated was proposed and demonstrated experimentally. A pair of FBGs with reflectivity of 92 % and 10 %, respectively, at the center wavelength of 1580 nm were inscribed in standard SMF-28 fibers without hydrogen loading by femtosecond laser point-by-point directly writing method, which was used as mirrors for wavelength selection of fiber laser, gratings full width at half maximum (FWHM) was less than 0.15 nm. A simple linear-cavity fiber laser was realized based on gain medium, pump source and FBGs. When gain medium of Er-doped fiber is selected 8 m, a stable single wavelength of 1579 nm laser with a 3 dB linewidth of 0.06 nm was obtained. Its output power is 24.1 mW when the maximum pump power is 600 mA, and its single wavelength of 1579 nm is consistent with the central wavelength of the fabricated FBGs. This type of laser source shows real promise for applications in coherent optical frequency domain reflectometry and high resolution fiber sensor systems.

Measuring gait kinematics in patients with severe hip osteoarthritis using wearable sensors

BackgroundThe popularity of inertial sensors in gait analysis is steadily rising. To date, an application of a wearable inertial sensor system for assessing gait in hip osteoarthritis (OA) has not been reported.Research question: Can the known kinematic differences between patients with hip OA and asymptomatic control subjects be measured using the inertial sensor system RehaGait®? MethodsThe patients group consisted of 22 patients with unilateral hip OA scheduled for total hip replacement. Forty-five age matched healthy control subjects served as control group. All subjects walked for a distance of 20 m at their self-selected speed. Spatiotemporal parameters and sagittal kinematics at the hip, knee, and ankle including range of motion (ROM) were measured using the RehaGait® system. ResultsPatients with hip OA walked at a slower walking speed (−0.18 m/s, P < 0.001) and with shorter stride length (−0.16 m, P < 0.001), smaller hip ROM during stance (−11.6°, P < 0.001) and swing (−11.3°, P < 0.001) and smaller knee ROM during terminal stance and swing (−9.0° and−11.5°, P < 0.001). Patients had a smaller hip ROM during stance and swing and smaller knee ROM during terminal stance and swing in the affected compared to the unaffected side (P < 0.001). SignificanceThe differences in spatiotemporal and kinematic gait parameters between patients with hip OA and age matched control subjects assessed using the inertial sensor system agree with those documented for camera-based systems. Hence, the RehaGait® system can measure gait kinematics characteristic for hip OA, and its use in daily clinical practice is feasible.

Dual interference effects in a line-by-line inscribed fiber Bragg grating.

Fiber Bragg grating (FBG) usually can be seen as a stack of Fabry-Perot (FP) cavities, which result in strong Bragg resonance through multi-cavity FP interference. In this Letter, we report surprising and interesting dual interference effects in a line-by-line (LBL) inscribed FBG with a femtosecond laser. Besides the well-known FP effect, the equivalent Mach-Zehnder interference (MZI) effect caused by mode interference can also be observed in the LBL FBG simultaneously. The experimental results of the comparison between the LBL FBGs and the point-by-point inscribed FBGs show that the dual interference effects are merely observed in the LBL FBGs. Meanwhile, the achieved MZI exhibits a strong polarization dependence. Sharing the merits of the FBG and MZI simultaneously, the achieved optical fiber device may find potential applications in optical fiber communication, fiber lasers, and multi-parameter sensor systems.

Aggregation State of Tetraphenylporphyrin Derivatives in Polymer Films Based on Poly-N-Vinylpyrrolidone

The spectral luminescent and electrophysical properties of polymer films based on poly-N-vinylpyrrolidone with the stabilized derivatives of tetraphenylporphyrin in various aggregation states (monomers, J- and H-aggregates) were investigated. Films containing a monomolecular form of porphyrins are characterized by intensive fluorescence. For films with J-aggregates an electric response that was not practically observed in the case of H-aggregates was detected. The films obtained are also characterized by optical and electric response to pH change, particularly in the presence of ammonia and hydrogen chloride vapors. The obtained data allow polymeric films with immobilized porphyrins to be considered as potential material for the creation of film systems for sensor applications, photovoltaics, molecular electronics, and photocatalysis. The variability of the film synthesis methodology allows the aggregation state of the immobilized porphyrins to be changed directionally, which provides the possibility of obtaining films of hybrid organic materials with the desired photophysical properties.

(Invited) High Temperature Smart Sensor Systems for Venus and Aerospace Applications

(Invited) High Temperature Smart Sensor Systems for Venus and Aerospace Applications

Mechanical and Electronic Video Stabilization Strategy of Mortars with Trajectory Correction Fuze Based on Infrared Image Sensor.

For a higher attack accuracy of projectiles, a novel mechanical and electronic video stabilization strategy is proposed for trajectory correction fuze. In this design, the complexity of sensors and actuators were reduced. To cope with complex combat environments, an infrared image sensor was used to provide video output. Following the introduction of the fuze’s workflow, the limitation of sensors for mechanical video stabilization on fuze was proposed. Particularly, the parameters of the infrared image sensor that strapdown with fuze were calculated. Then, the transformation relation between the projectile’s motion and the shaky video was investigated so that the electronic video stabilization method could be determined. Correspondingly, a novel method of dividing sub-blocks by adaptive global gray threshold was proposed for the image pre-processing. In addition, the gray projection algorithm was used to estimate the global motion vector by calculating the correlation between the curves of the adjacent frames. An example simulation and experiment were implemented to verify the effectiveness of this strategy. The results illustrated that the proposed algorithm significantly reduced the computational cost without affecting the accuracy of the motion estimation. This research provides theoretical and experimental basis for the intelligent application of sensor systems on fuze.

Metamaterial waveguides as integrated optics sensor

We study sensors based on metamaterial cladded waveguides for monitoring gas or liquid specimens. These multilayer structures are made of metal and dielectric thin film claddings, surrounding a hollow core. Mechanical strength, electromagnetic interference immunity, compact layout and connection reliability, make them appropriate to indoor or open air sensing system applications. Sensitivity to sample dielectric constant optical response is numerically calculated and analyzed in different metamaterial sensor designs.

Pattern-recognition-based Sensor Arrays for Cell Characterization: From Materials and Data Analyses to Biomedical Applications.

To capture a broader scope of complex biological phenomena, alternatives to conventional sensing based on specificity for cell detection and characterization are needed. Pattern-recognition-based sensing is an analytical method designed to mimic mammalian sensory systems for analyte identification based on the pattern recognition of multivariate data, which are generated using an array of multiple probes that cross-reactively interact with analytes. This sensing approach is significantly different from conventional specific cell sensing based on highly specific probes, including antibodies against biomarkers. Encouraged by the advantages of this technique, such as the simplicity, rapidity, and tunability of the systems without requiring a priori knowledge of biomarkers, numerous sensor arrays have been developed over the past decade and used in a variety of cell sensing applications; these include disease diagnosis, drug discovery, and fundamental research. This review summarizes recent progress in pattern-recognition-based cell sensing, with a particular focus on guidelines for designing materials and arrays, techniques for analyzing response patterns, and applications of sensor systems that are focused primarily for the biomedical field.

Application of an inductive sensor system for identifying ripeness and forecasting harvest time of oil palm

Ripeness estimation of oil palm fresh fruit bunches is a crucial component in the management of oil palm harvesting, as it will lead to profitability and marketability of the product. The purpose of this study is to develop an oil palm maturity detection device that is not only able to identify oil palm maturity, but also predict harvest time. In this work, the resonant frequency data were collected using an inductive sensor from a total of 600 fruits at various ages of ripeness. Intelligent algorithms are embedded into the system to recognize the oil palm ripeness, i.e., discriminant analysis for identifying ripeness and polynomial regression for forecasting harvest time. In oil palm plantations, we prepared 55 fresh fruit bunches to identify their ripeness and forecast harvest time. Based on the field test performance, the inductive sensor system can determine the oil palm ripeness with an accuracy of 100 % and forecast the harvest time with RMSE of 13.45. Therefore, the proposed system has the potential to be implemented in the evaluation of harvesting oil palm due to its various advantages, i.e., being accurate, rapid and non-invasive.

Highly Stable Upconverting Nanocrystal-Polydiacetylenes Nanoplates for Orthogonal Dual Signaling-Based Detection of Cyanide.

Although the unique optical signaling properties of polydiacetylene (PDA) have been exploited in diverse bio-chemosensors, the practical application of most PDA sensor systems is limited by their instability in harsh environments and fluorescence signal weakness. Herein, a universal design principle for a highly stable PDA sensor system with a practical dual signaling capability is developed to detect cyanide (CN) ions, which are commonly found in drinking water. Effective metal intercalation and enhanced hydrophobic intermolecular interactions between PDA-metal supramolecules are used to construct highly stacked PDA-metal nanoplates that feature unusual optical stability upon exposure to strong acids, bases, organic solvents, and thermal/mechanical stresses, and can selectively detect CN anions, concomitantly undergoing a specific supramolecular structure change. To realize the practical dual signaling capability of the PDA sensor system, upconverting nanocrystals (UCNs) are incorporated into highly stacked PDA-metal nanoplates, and practical dual signaling (orthogonal changes in luminescence and visible color) is demonstrated using a portable detection system. The presented universal design principle is expected to be suitable for the development of other highly stable and selective PDA sensor systems with practical dual signaling capability.

Determination of the Aspect-ratio Distribution of Gold Nanorods in a Colloidal Solution using UV-visible absorption spectroscopy

Knowledge of the distribution of the aspect ratios (ARs) in a chemically-synthesized colloidal solution of Gold Nano Rods (GNRs) is an important measure in determining the quality of synthesis, and consequently the performance of the GNRs generated for various applications. In this work, an algorithm has been developed based on the Bellman Principle of Optimality to readily determine the AR distribution of synthesized GNRs in colloidal solutions. This is achieved by theoretically fitting the longitudinal plasmon resonance of GNRs obtained by UV-visible spectroscopy. The AR distribution obtained from the use of the algorithm developed have shown good agreement with those theoretically generated one as well as with the previously reported results. After bench-marking, the algorithm has been applied to determine the mean and standard deviation of the AR distribution of two GNRs solutions synthesized and examined in this work. The comparison with experimentally derived results from the use of expensive Transmission Electron Microscopic images and Dynamic Light Scattering technique shows that the algorithm developed offers a fast and thus potentially cost-effective solution to determine the quality of the synthesized GNRs specifically needed for many potential applications for the advanced sensor systems.

Recent Progress in Wireless Sensors for Wearable Electronics

The development of wearable electronics has emphasized user-comfort, convenience, security, and improved medical functionality. Several previous research studies transformed various types of sensors into a wearable form to more closely monitor body signals and enable real-time, continuous sensing. In order to realize these wearable sensing platforms, it is essential to integrate wireless power supplies and data communication systems with the wearable sensors. This review article discusses recent progress in wireless technologies and various types of wearable sensors. Also, state-of-the-art research related to the application of wearable sensor systems with wireless functionality is discussed, including electronic skin, smart contact lenses, neural interfaces, and retinal prostheses. Current challenges and prospects of wireless sensor systems are discussed.