Good Response Time Research Articles

Classical and quantum regression analysis for the optoelectronic performance of NTCDA/p-Si UV photodiode

Due to the pivotal role of UV photodiodes in many technological applications in tandem with the high efficiency achieved by machine learning techniques in regression and classification problems, different artificial intelligence techniques are adopted to simulate and model the performance of organic/inorganic heterojunction UV photodiode. Herein, the performance of a fabricated Au/NTCDA/p-Si/Al photodiode is explained in a detailed manner and has shown an excellent responsivity and detectivity for UV light of intensities ranging from 20 to 80mW/cm2. A linear current–irradiance relationship is exhibited by the fabricated photodiode under illumination up to 65mW/cm2. It also shows good response times of trise=408ms and tfall=490ms. Furthermore, we have not only fitted the characteristic I-V curve but also evaluated three classical algorithms; K-Nearest Neighbour, Artificial Neural Network, and Genetic Programming besides using a Quantum Neural Network to predict the behavior of the device. The models have achieved outstanding results and managed to capture the trend of the target values. The Quantum Neural Network has been used for the first time to model the photodiode characteristics. The trained models are of great significance since they can be used to reduce the characterization and measurement times.

The Relationship between the Number of Emergency Room Patient Visits with Triage Accuracy and Emergency Nurse Response Time in the Covid 19 Pandemic Season

Handling emergency cases must not only be carried out quickly but also must be precise. Standard Operating Procedures (SOP) is one of the instruments to measure the quality of service. the number of patient visits that can affect the quality of service. Triage is a way of sorting patients based on therapy needs and available resources. Therapy is based on ABC conditions (Airway, with cervical spine control, Breathing, and Circulation with bleeding control). On the other hand, the COVID-19 pandemic greatly affects the response time, impacting the number of patient visits. Response time is the time between the beginning of a request being responded to in other words it can be called response time. A good response time for patients is 5 minutes. The purpose of this study was to identify the relationship between the number of patient visits and the accuracy of triage implementation and response time. The electronic database used is PubMed, Springer, and Google Scholar with a search strategy using the PICO (patient, intervention, comparison, and outcome) method.

Fabrication of a Conductive Poly(3,4-ethylenedioxythiophene)-Coated Polyester Nonwoven Fabric and Its Application in Flexible Piezoresistive Pressure Sensors

Poly(3,4-ethylenedioxythiophene)-coated nonwoven fabric (PEDOT@NWF) composites were prepared using ordinary polyester needle-punched nonwoven fabrics as substrates via in situ vapor phase polymerization (VPP) technique. The prepared PEDOT@NWF conductive composite has a uniform PEDOT coating on the surface of the fibers. Factors which may affect the polymerization effect, such as oxidant concentration, reaction time, and other parameters were explored, and a series of morphological, structural, and electrical properties of the prepared conductive nonwoven fabrics were analyzed. Furthermore, for comparison, piezoresistive pressure sensors with two different assembly methods (vertical electrode and horizontal electrode) were made utilizing the PEDOT@NWF material. The pressure sensing performance has also been evaluated and the as-prepared sensors exhibit good sensitivity and fast response time.

Amine mediated synthesis of nickel oxide nanoparticles and their superior electrochemical sensing performance for glucose detection

Nickel based materials with nanoscale is great attention in various electrochemical application owing to their good redox characteristics, easy preparation, low cost and less toxic in nature. In the present work, simple and ultra-small size of nickel oxide nanoparticles (NiO NPs) was prepared by simple calcination of nickel and p-Phenylene diammine complex. The synthesized NiO NPs were studied by FE-SEM, XRD, and cyclic voltammetry. The NiO NPs modified glassy carbon electrode (GCE) demonstrated good electro-catalytic performance for glucose oxidation with higher oxidation peak current (ipa :46.9 ± 0.2 µA) when correlated to that of bulk NiO (ipa : 10.3 ± 0.3 µA) and unmodified GCE (ipa: 1.7 ± 0.3 µA) electrodes. Further, the NiO NPs coated electrode surface exhibited good linear range (5 µM–2.49 mM), high sensitivity (0.310 µA µM−1 cm−2), low detection limit (3.5 µM), good response time (<f5 s), selectivity, and stability. The optimized work was successfully utilized for accurate determination of glucose in blood serum sample.

Electrochromic Performance and Capacitor Performance of α-MoO3 Nanorods Fabricated by a One-Step Procedure

In this paper, we propose for the first time the synthesis of α-MoO3 nanorods in a one-step procedure at mild temperatures. By changing the growth parameters, the microstructure and controllable morphology of the resulting products can be customized. The average diameter of the as-prepared nanorods is about 200 nm. The electrochromic and capacitance properties of the synthesized products were studied. The results show that the electrochromic properties of α-MoO3 nanorods at 550 nm have 67% high transmission contrast, good cycle stability and fast response time. The MoO3 nanorods also exhibit a stable supercapacitor performance with 98.5% capacitance retention after 10,000 cycles. Although current density varies sequentially, the nanostructure always exhibits a stable capacitor to maintain 100%. These results indicate the as-prepared MoO3 nanorods may be good candidates for applications in electrochromic devices and supercapacitors.

Fabricating a highly sensitive graphene nanoplatelets resistance-based temperature sensor

PurposeThis study aims to present an efficient and reliable graphene nanoplatelets (GNPs)-based temperature sensor.Design/methodology/approachA high-quality dispersion of GNPs was dropped by casting method on platinum electrodes deposited on a polyethylene terephthalate (PET) substrate. The GNPs were characterized by scanning electron microscope, Raman spectroscopy and X-ray diffraction spectra to ensure its purity and quality. The temperature sensing behavior of the fabricated sensor was examined by subjecting it to different temperatures, range from room temperature (RT) to 150 °C.FindingsExcellent resistance linearity with temperature change was achieved. Temperature coefficient of resistance of the fabricated sensor was calculated as 1.4 × 10–3°C. The sensor also showed excellent repeatability and stability for the measured temperature range. Good response and recovery times were evaluated at all the measured temperatures. With measuring the sensor response, the ambient temperature can be determined.Originality/valueThe present work presents a new simply and low cost fabricated temperature sensor based on GNPs working at a wide temperature range.

Development of a rGO-BiVO4 Heterojunction Humidity Sensor with Boosted Performance.

Humidity sensors with good repeatability, low hysteresis, and low-power consumption are increasingly important for environmental monitoring and industrial control applications. Herein, an impedance-type humidity sensor under low working voltage (5 mV) utilizing a rGO-BiVO4 nanocomposite is demonstrated. The rGO-BiVO4 humidity sensor exhibits superior sensing performances, including good repeatability, negligible hysteresis (0.47%), fast response and recovery time, low power consumption, good stability, and anti-interference ability. The ultraviolet-visible absorption spectrum reveals that the narrow band gap of the rGO-BiVO4 nanocomposite is conductive to the electron transfer. The complex impedance spectra and the energy band structure analysis further suggest that the boosted humidity performance results from the formation of a heterojunction and the decrease of the heterojunction barrier height. The facile fabrication route, enhanced sensing performance, and excellent device reliability make the rGO-BiVO4 sensor highly attractive for high-end humidity sensing applications.

A Comparative Study between V/F and IFOC Control for Three-Phase Induction Motor Drives

The voltage/frequency “(V/F) control” method is considered as widely used method in industrial application for control the induction motor (IM) due to its simplicity and lower the cost. The main problems in this method are the slow response, and it cannot be applied in the applications that required smooth speed control. To solve these problems, a roust control method of indirect field-oriented control (IFOC) was developed. In this paper, a comparative study of classical V/F control and IFOC of 3-ph IM is done. The principle action for both methods are studied and then they implemented and simulated using “MATLAB/Simulink” software for a 10 HP (7.457kw) 3-ph squirrel cage type IM. Besides, the sinusoidal pulse width modulation (SPWM) technique with a proportional-integral (PI) controller has been used to control the VSI inverter in the V/F method. While, the space vector PWM (SVPWM) technique has been used to control the VSI inverter in the IFOC method. The 3-ph IM has been achieved to its desired speed with good transient time and steady state response when the step change in the torque load has applied. Therefore, the IFOC method provides smooth speed control, high performance, and fast response under different dynamic conditions compared to classical V/F method.

Preparation and humidity sensing behavior of cadmium – zinc ferrite nanocomposite

Cadmium Zinc ferrite (Cd0.8Zn0.2Fe2O4) nano-composites (NC) were prepared by auto-combustion method, and annealed at 650°C. The humidity sensing behavior of this composite has been studied. The ability of a ferrite to sense the ambient water molecules depends on their interaction with ferrite material’s porous surface. The Cd0.8Zn0.2Fe2O4NC samples exhibit a high value of sensitivity to humidity, equal to 1.483 M?/%RH; this high sensitivity is due to two reasons. The first reason for this is the porous morphology of the prepared NC samples, confirmed from the SEM images. The second reason is the low value of crystallite size as more active sites for adsorption and desorption of water molecules become possible when the crystallite size is reduced. The humidity sensing behavior of the prepared composite films, based on electrical impedance measurements, exhibit an excellent reproducibility of 98%, as well as good response and recovery times of 86 seconds and 44 seconds, respectively. Therefore, it is a good candidate for humidity sensing applications.

PCB mounted sensor with high sensitivity SWNT-Based devices for gas sensing applications

In this paper, the fabrication of aligned semiconducting single-walled carbon nanotube (SWNT) devices on a thermally grown silicon dioxide (SiO2) over silicon (Si) substrate is presented. The SWNTs are aligned between the nickel fingers that are patterned on the substrate. Subsequently, the fabricated devices are bonded onto a low-cost printed circuit board (PCB) with wire bonder. The mounted sensors have been tested for carbon dioxide (CO2) gas, acetone, and isopropyl alcohol (IPA) vapor sensing at room temperature. The sensitivity values of 27% for the concentration of 15000 ​ppm of CO2, 52% for the concentration of 7000 ​ppm of acetone, and 67% for the concentration of 900 ​ppm of IPA have been observed with good response and recovery times. The fabricated sensors show better performance than the already reported sensors.

Printed Acoustic Sensor for Low Concentration Volatile Organic Compound Monitoring

Printed electronics employing flexible substrate offers prospective features for various applications such as, tactile sensing, energy harvesting, wearable electronics and acoustic wave sensors. In this work, an acoustic FPW (flexural plate wave) sensor is printed on thin and flexible PZT-PDMS (lead zirconate titanate-poly dimethyl siloxane) composite film with silver ink. The prototype FPW resonator has a resonant frequency of 22.65 MHz with an attenuation of -1.552 dBm. Gravimetric mass sensitivity of the sensor was measured by applying PDMS layers in between the input and output interdigital transducers (IDTs). The mass sensitivity was measured to be -7.8 cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> /g. The sensor is highly responsive to VOCs (volatile organic compounds) with PDMS as a sensing layer. Gas sensitivities with acetic acid and toluene concentrations were measured to be 0.66 and 160.63 kHz/ppm, respectively. The limit of detection for acetic acid and toluene were 10.9 and 0.03 ppm, respectively. Further, the sensor shows good repeatability and response time with both the VOCs. The thermal stability and high piezoelectric charge coefficient of PZT-PDMS composite compared to other piezoelectric composite and polymer substrates are advantageous for the flexible printed sensor. The reported FPW gas sensor shows potential for low concentration measurement of VOCs.

A Study on Re-Engagement and Stabilization Time on Take-Over Transition in a Highly Automated Driving System

In the case of level 3 automated vehicles, in order to safely and quickly transfer control authority rights to manual driving, it is necessary that a study be conducted on the characteristics of human factors affecting the transition of manual driving. In this study, we conducted three experiments to compare the characteristics of human factors that influence the driver’s quality of response when re-engaging and stabilizing manual driving. The three experiments were conducted sequentially by dividing them into a normal driving situation, an obstacle occurrence situation in front, and an obstacle and congestion on surrounding roads. We performed a statistical analysis and classification and regression tree (CART) analysis using experimental data. We found that as the number of trials increased, there was a learning effect that shortened re-engagement times and increased the proportion of drivers with good response times. We found that the stabilization time increased as the experiment progressed, as obstacles appeared in front and traffic density increased in the surrounding lanes. The results of the analysis are useful for vehicle developers designing safer human–machine interfaces and for governments developing guidelines for automated driving systems.

Pseudo n-type behaviour of nickel oxide thin film at room temperature towards ammonia sensing

Sensors are part of a safe laboratory, working space and closed environment. In view of this, a sensing material for ammonia (NH3) vapour, nickel oxide (NiO) has been investigated to improve its quality as a sensor. The transparent nanostructured NiO thin films were deposited on glass substrates by sol-gel spin coating method at different molar concentrations (0.4 M, 0.6 M and 0.8 M). The NH3 sensing studies reveal that 0.6 M film shows admirable response of 403 (75 ppm), and also it has good response and recovery times (110 s and 33 s) for 25 ppm at room temperature. These features of the film are attributed to low surface roughness, small grain size and higher surface to volume ratio compared to other films. In presence of air ambience, the electrons at film surface are chemisorbed by oxygen molecules and thereby cause an increase of the depletion layer. Once the film is exposed to the analyte gas NH3, the depletion layer decreases because of electrons returning back to the conduction band (CB). These electrons are then de-excited to the valence band (VB) and recombine with holes (annihilation of holes). At the same time, the trapping of electrons by Ni(OH)2 and creation of holes by oxidation of Ni2+ into Ni3+ increases the hole concentration at VB, followed by a reduction of recombination rate of electrons and holes. All these processes decrease the potential barrier between the grains and thereby cause the Fermi level (EF) to shift towards VB. These processes remarkably enhance the sensing behaviour of the film. Importantly, the prepared NiO thin film behaves as a n-type sensor at room temperature for NH3; and therefore, termed as pseudo-n-type.

Field Oriented Control of Doubly Fed Induction Motor using Speed Sliding Mode Controller

This article presents a modeling and control of the Doubly Fed Induction Motor (DFIM), associated with two inverters controlled through the Pulse Width Modulation technique (PWM), the control of the DFIM is carried out by the approach of Rotor Flux Oriented Control (RFOC) according to the direct axis. In this approach, regulation is done by classic PI regulators, the latter having undesirable overruns and static errors in non-linear systems, for that the introduction of the control by sliding mode in place of the classic PI speed regulator, that is in the form of a control law based on this type of controller since it is invariant to the non-linearity of the system and precise, stable, simple and has a good response time, in order to validate the objectives of improving the DFIM behavior in front of the reference parameters, such as the speed and the torque imposed on the machine. The results of the proposed approach are validated by its implementation on the Matlab/Simulink environment.

Porous Platinum Black-Coated Minimally Invasive Microneedles for Non-Enzymatic Continuous Glucose Monitoring in Interstitial Fluid.

Individuals with diabetes can benefit considerably from continuous blood glucose monitoring. To address this challenge, a proof-of-concept was performed for continuous glucose monitoring (CGM) based on an enzymeless porous nanomaterial (pNM)-modified microneedle electrode array (MNEA). The pNM sensing layer was electrochemically deposited on MNs by applying a fixed negative current of −2.5 mA cm˗2 for 400 s. The pNM-modified MNEA was packed using a biocompatible Nafion ionomer. The fabricated MNEAs were 600 × 100 × 150 µm in height, width, and thickness, respectively. The surfaces of the modified MNs were characterized by scanning electron microscopy (SEM) and energy dispersive X-ray analysis (EDX), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). The fabricated MNEAs showed a wide dynamic range (1–30 mM) in phosphate-buffered saline (PBS) and in artificial interstitial fluid (ISF), with good sensitivities (PBS: 1.792 ± 0.25 µA mM−1 cm−2, ISF: 0.957 ± 0.14 µA mM−1 cm−2) and low detection limits (PBS: 7.2 µM, ISF: 22 µM). The sensor also showed high stability (loss of 3.5% at the end of 16 days), selectivity, and reproducibility (Relative standard deviations (RSD) of 1.64% and 0.70% for intra- and inter-assay, respectively) and a good response time (2 s) with great glucose recovery rates in ISF (98.7–102%).

Greener and facile synthesis of hybrid nanocomposite for ultrasensitive iron (II) detection using carbon sensor

Abstract Novel hybrid nanocomposite has been developed using an environmentally friendly method. The new hybrid nanocomposite was synthesized in two green steps at ambient conditions as graphite decorated with gold nanoparticles and then coated with polypyrrole chains through solvent-less vapor polymerization method. Developed graphite–gold nanoparticles-polypyrrole (GR-AuNP-PPY) nanocomposite has been explored as an effective electroactive material for preparing iron (II) ion-selective carbon paste electrode. The developed nanocomposite mass loadings in the fabricated carbon sensor were varied from 12 to 72 mg. The electrode incorporating 56 mg of GR-AuNP-PPY exhibited an excellent bivalent Nernstian slope value of 30.0 ± 0.23 mV decade−1 over a perceptible spacious concentration range of 1.0 × 10−6 – 1.0 × 10−2 mol L−1 within pH range from 2.5 to 5.5 displaying a fast response time of 3 s. The proposed GR-AuNP-PPY based sensor revealed a good discriminating power of iron (II) ion over numerous metal ions. The analytical applicability of the GR-AuNP-PPY based electrode has been investigated for the quantitative detection of iron (II) ion in spiked water samples using the calibration curve method. The aforementioned sensor displayed excellent selectivity, good response time, high accuracy and precision. Additionally, the mechanism of electroactive material interaction with iron (II) was investigated and found to be an ion imprinting like mechanism.

High-performance field-effect transistor glucose biosensors based on bimetallic Ni/Cu metal-organic frameworks

Accurate detection of glucose is essential for the diagnosis of diabetes, wherein effective and sensitive biosensors for glucose detection are needed. Here, we fabricated a glucose sensor based on field-effect transistor (FET) with bimetallic nickel-copper metal-organic frameworks (Ni/Cu-MOFs) as its channel layers which were grown in-situ through a simple one-step hydrothermal method and modified with glucose oxidase (GOD) by using glutaraldehyde (GA) as linkers. Due to the synergistic effect of Ni ions and Cu ions in MOFs, the sensor (GOD-GA-Ni/Cu-MOFs-FET) showed good field effect performance and great responses to glucose through enzymatic reactions. It displayed a piecewise linear relationship in the wide range (1 μM–20 mM), and provided high sensitivity (26.05 μAcm−2mM−1) in the low concentration (1–100 μM) and a low detection limit (0.51 μM). The sensor also had these advantages of high specificity, excellent reproducibility, good short-term stability and fast response time. Especially, it is indicated that the Ni/Cu-MOFs-FETs with high performance have the potential to be available sensors, paving the way for the application of bimetallic MOFs in biosensing.

A Fast Simulation Tool for Silicon-Pad Detectors

Several types of detectors are used to detect charged particles in particle and nuclear physics experiments. Since the semiconductor detector has superior spatial and kinematic resolutions as well as good response time than other types of detectors, it has become one of the most important detectors recently. When charged particles pass through the semiconductor detector, electron-hole pairs are formed inside the detector and move toward the electrode by the electric field inside the detector. At this time, the trajectory and momentum can be determined through the generated current signal. In this study, we introduce an open-source application named Fast Silicon Device Simulation that is developed for fast simulation of a typical silicon semiconductor detector, such as a p-type pad on an n-type wafer with a reverse-bias voltage. Iterative and multi-grid methods are used to calculate the potential and electric field in the simulation fast. Current signals produced by the simulation are compared with results by Silvaco TCAD and Garfield++ simulations. The simulation program is based on the ROOT that has been developed by CERN.

Dual physically cross-linked carboxymethyl cellulose-based hydrogel with high stretchability and toughness as sensitive strain sensors

Hydrogel-based strain sensors have been widely investigated owing to their intrinsic flexible and extensible properties. However, integrating good mechanical properties and excellent strain sensitivity into one hydrogel remains a challenge. In this work, a dual physical cross-linked carboxymethyl cellulose-Fe3+/polyacrylamide (CMC-Fe3+/PAAm) double network hydrogel was developed by facile two-step method. In this hydrogel, the Fe3+ cross-linked CMC acts as the first network for dissipating energy and hydrophobic association PAAm acts as the second network to maintain the integrity of hydrogel. Owing to these physical interactions, the as-prepared hydrogel shows good mechanical properties (e.g., tensile strength, 1.82 MPa; toughness, 6.52 MJ/m3). Furthermore, these mechanical behaviors can be modulated by adjusting the solid content, CMC/PAAm ratio, Fe3+ concentration and soaking time in Fe3+ solution. Moreover, the obtained hydrogel shows excellent self-recovery and anti-fatigue property due to the reversibility of dual physical cross-linked interactions. Additionally, the CMC-Fe3+/PAAm hydrogel shows good conductivity (1.82 S/m), strain sensitivity (gauge factor = 4.02 at 50–600% strain), and fast response time (260 ms). Based on the high strain sensitivity, the CMC-Fe3+/PAAm hydrogel can fabricate a flexible strain sensor for precisely monitoring various human motions. This study suggests that the CMC-Fe3+/PAAm hydrogel exhibits potential application in the flexible and stretchable strain sensors.

Development of a Low-Cost Portable Gas Sensing System Based on Molecularly Imprinted Quartz Crystal Microbalance Sensor for Detection of Eugenol in Clove Oil

A low-cost portable gas sensing system for the detection of eugenol in clove oil is described in this article. The sensor has been developed on a molecularly imprinted polymer (MIP) modified quartz crystal microbalance (QCM) platform. The system has two parts: 1) MIP-QCM sensor and 2) sensor signal measuring unit, which includes a crystal oscillator (10 MHz), a frequency counter (ATmega328P microcontroller unit), a liquid crystal display (LCD), and a data storage unit. A 10-MHz AT cut quartz crystal was coated with the synthesized solution of the optimum ratio of styrene, methyl methacrylate, and divinylbenzene with eugenol as the template. A crystal oscillator based on a simple complementary metal-oxide-semiconductor inverter and ATmega328 microcontroller were used for data generation and transfer. The portable instrument was used for the detection of eugenol in clove oil samples, which revealed reasonably good repeatability (96.37%), reproducibility (92.92%), and fast response time of about 1 min. The system could detect the concentration of eugenol at ppm level in different real samples. Finally, the response of the proposed system was correlated with the response obtained from gas chromatograph.