- 标题
- 摘要
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- 实验方案
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Power Efficiency Figure of Merit for Image Sensors
摘要： A new figure of merit (FoM) is developed with a theory, which enables the comparison of power efficiency of different image sensors based only on the pixel array size, frame rate, and total power consumption. The mathematical foundation of the FoM is provided, enabling the application of FoM to a generic image sensor supporting various read-out configurations. The model assumes a nonlinear relationship between the power consumption and operating frequency of building blocks, and the nonlinear factor is numerically derived based on the analytical modeling of image sensors. The FoM is applied to the studies from 1999 to 2018, which clarifies the trend of improvement as well as visualizes several breakthroughs in the development history.
关键词： modeling,CMOS image sensor (CIS),power efficiency,figure of merit (FoM),power consumption
更新于2025-09-23 15:23:52
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[IEEE 2018 IEEE ANDESCON - Santiago de Cali (2018.8.22-2018.8.24)] 2018 IEEE ANDESCON - Obstacle Detection System to Improve Mobility of People with Visual Impairment
摘要： Visual information is one of the most important factors in the perception of the environment. People with Visual Impairment (VI) have many limitations to explore unfamiliar environments since they lack of vision. Previous works, carried out by other researchers, focus on helping people suffering from VI by using different technologies to improve environment percept, however, none of them analyzes the possibility of avoiding frontal obstacles at face height. That is why in this article we propose a system for detecting obstacles in the superior frontal plane to improve the mobility of people with VI. The proposed system is based on ultrasound sensors and an Android application to process and communicate useful information. The system is low cost, wireless, ergonomic and user friendly. The results indicate that the system is capable of detecting (on average) 80% of frontal obstacles at face height. The implementation of the proposed system can improve the quality of life of people suffering from VI, providing independence in mobility in unfamiliar environments.
关键词： Ad-Hoc,WiFi,sensor de ultrasonido,Discapacidad visual,ciegos,RFID,Invidentes
更新于2025-09-23 15:23:52
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Multi-Parameters Detection Implemented by LC Sensors With Branching Inductors
摘要： Inductor-capacitor (LC) sensors utilize magnetic coupling to transfer signals to the readout coil, realizing a passive wireless working pattern. They are of high use in situations where wired connections are impossible to be established. An increasing number of demands, arising from the emerging applications in the Internet of Things and portable devices, require a simultaneous monitoring in sensors. This paper proposes a branching inductor to implement multiple resonances in a single inductor. Each branch of the inductor forms a secondary inductance, which is connected with a sensitive capacitor to work as an LC sensor. The multiple resonances in the branching inductor work in a multi-mode coupling pattern. The coupling, comprising inductive coupling, and capacitive coupling is analyzed and detected. In experiments, a double branching inductor is fabricated on PET substrate. Two sensitive capacitors for humidity and pressure, respectively, are connected to the inductor, resulting in two resonant peaks to monitor the ambient humidity and pressure level. The experimental results are decoupled to obtain final outcomes: the humidity sensor can respond from 15%RH ~ 90%RH with a sensitivity of -45.3 kHz/%RH; and the pressure sensor can work from 750 mmHg ~ 1000 mmHg with a sensitivity of -811.2 kHz/mmHg.
关键词： Branching inductor,LC sensor,multi-parameter
更新于2025-09-23 15:23:52
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Passive Sub-Carrier Multiplexing for Discriminating Overlapped Optical Spectra
摘要： A passive technique for multiplexing spectrally overlapping optical network signals is proposed and experimentally verified. The system utilizes arrayed fiber delay lines for multiplexing signal generation and offers simultaneous plotting of multiple optical spectra. Accurate recovery of individual spectrum of multiplexed long-period gratings spectra is experimentally demonstrated in a refractive index sensing application. This system provides an all-optical platform for economical multiplexing system in optical sensing networks.
关键词： Multiplexing scheme,optical sensor network,temporal shifting
更新于2025-09-23 15:23:52
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Manganese-doped zinc oxide hollow balls for chemiresistive sensing of acetone vapors
摘要： Both pure and Mn(II)-doped ZnO hollow structures were synthesized by a solvothermal reaction, and their phase structures, morphologies and elemental composition were characterized. SEM and TEM observations show the pure ZnO and the Mn(II)-doped ZnO balls to possess similar hollow structure with a particle size of about 1.5 μm. Their sensing properties were investigated, and the composite containing 1 atom% of Mn(II) (1% Mn-ZnO) is found be display the highest selectivity for acetone. The detection limit is 100 ppm acetone at 234 °C which is 4.6 times lower than that of the pure ZnO. In addition, the response time is shorter.
关键词： Hollow balls,Gas sensor,ZnO,Acetone vapors,Mn-doped ZnO
更新于2025-09-23 15:23:52
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A Simple Colorimetric and Fluorescent Sensor to Detect Organophosphate Pesticides Based on Adenosine Triphosphate-Modified Gold Nanoparticles
摘要： A simple and dual modal (colorimetric and fluorescent) sensor for organophosphate pesticides with high sensitivity and selectivity using adenosine triphosphate (ATP)- and rhodamine B-modified gold nanoparticles (RB-AuNPs), was successfully fabricated. This detection for ethoprophos afforded colorimetric and fluorescence imaging changes visualization. The quantitative determination was linearly proportional to the amounts of ethoprophos in the range of a micromolar scale (4.0–15.0 μM). The limit of detection for ethoprophos was as low as 37.0 nM at 3σ/k. Moreover, the extent application of this simple assay was successfully demonstrated in tap water samples with high reliability and applicability, indicating remarkable application in real samples.
关键词： multimodal assay,ethoprophos detection,gold nanoparticles,colorimetric and fluorescent sensor,organophosphate pesticides
更新于2025-09-23 15:23:52
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Construction of an oxygen detection-based optic laccase biosensor for polyphenolic compound detection
摘要： A fiber optic biosensor was constructed from Pleurotus ostreatus laccase for the detection of polyphenolic compounds. Laccase was immobilized on the surface of the commercially available fiber optic oxygen sensor spots by using 3-aminopropylsilanetriol, tetramethyl orthosilicate (TMOS), glutaraldehyde, and amino-modified carboxycellulose. A diffusion layer containing trimethoxymethylsilane (Tri-MOS), and polyvinyl alcohol (PVA) was added to the immobilized laccase layer. The consumption of oxygen as a result of laccase activity was monitored using a fiber optical measuring setup with catechol as a model substrate. The optimal enzyme amount was determined as 1.5 mg per 50 μL of enzyme layer mixture, and with one diffusion layer and at pH 6.9, optimum detection conditions were attained. The biosensors have high reproducibility, stability (at least 85 days if stored in PBS at 4 °C), and convenient measurement duration (ca. 25 min between two successive measurements). The biosensor was found to have a broad linear working range for catechol (40–600 μM) and to be applicable to a flow-through system. In summary, an easy-to-produce, reproducible, and stable laccase sensor with a broad linear working range was produced. The sensor has potential in the food industry as well as in environmental monitoring for the detection of phenolic compounds.
关键词： catechol,phenolic compounds,oxygen-based optic sensor,Laccase biosensor
更新于2025-09-23 15:23:52
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Underwater optical wireless sensor networks using resource allocation
摘要： Optical wireless communications is an energy efficient and cost-effective solution for high speed and high secure wireless connections. In this paper, we propose an underwater optical wireless sensor network using multiple input multiple output technique and power allocation algorithm for supporting multiple users with the impacts of underwater channel uncertainty interferences. In proposed power allocation algorithm, all the LED nodes in are coordinated and controlled by a central controller; each LED node supports all the users within its field of view. To separate users, optical code division multiple access is used; cyclic optical orthogonal code working as CDMA code is employed. At the receiver, a minimal mean squared error (MMSE) filter is uniquely designed for each user. The MMSE filters and the assigned power can be jointly optimized to improve the overall throughput and signal to noise ratio. Since the system performance may be impacted by the underwater channel uncertainty, the proposed power allocation can use the predicted channel uncertainty variance to reduce the interference of the channel uncertainty and improve the signal to noise ratio. Compared to the equal power allocation algorithm, the proposed algorithm can support longer transmission distance, higher bit rate and lower bit error rate.
关键词： Multiple access interference,Underwater communications,Wireless sensor networks,Channel uncertainty,MIMO system,CDMA,Optical wireless communications,Resource allocation
更新于2025-09-23 15:23:52
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A smartphone-based system for fluorescence polarization assays
摘要： This paper demonstrates the use of a smartphone-based sensor for fluorescence polarization (FP) analysis of biomolecules. The FP detection can rapidly sense ligand-analyte bindings by measuring molecule mobility, and thus, FP-based assays have been widely used for rapid diagnostics in clinics. Here, we implemented the FP detection apparatus using a 3D-printed compact holder and the built-in camera of a smartphone. The system offers accurate measurements of the degree of polarization by simultaneously detecting the fluorescence intensities parallel and perpendicular to the polarization of the excitation. The fluorescence signal of the sample is excited by a laser or light-emitting diode and separated by a polarization beam cube depending on the polarization. Parallel and perpendicular polarized emissions are projected onto two different regions of the sensor chip in the smartphone camera. A custom software app was developed to count the average intensity in the areas of interest and compute the degree of polarization. We validated the system by measuring the polarization of dye molecules dissolved in solutions with different viscosities. As an example of biomolecule sensing, a competitive FP immunoassay of Prostaglandin E2 was demonstrated using the developed system and exhibited the limit of detection of 1.57 ng/mL. The smartphone-based FP assay platform can also be implemented for the detection of toxins, disease biomarkers, and pathogens in resource-limited settings.
关键词： immunoassay,mobile sensor,fluorescence polarization assay,smartphone
更新于2025-09-23 15:23:52
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Advancement of CMOS Transimpedance Amplifier for Optical Receiver
摘要： Transimpedance amplifier (TIA) is an essential component of optical receivers, and this type of amplifier converts the photocurrent to a voltage signal. The overall performance of the optical receiver greatly depends on the performance of this component. Low-power, low-noise, and compact TIA has been realized in current development in CMOS technology. The high demands of an optical receiver has led to the optimization and development of the TIA designed specifications. However, the conventional CMOS TIA design is limited mainly because of its dependency on input node capacitance. In this article, the advancement of TIAs in data communication and instrumentation based on different design architectures and performances is discussed. This review will serve as a comparative study and reference for designing fully integrated CMOS TIA for future optical receivers.
关键词： TIA,Gain,CMOS,Sensor,Optical receiver
更新于2025-09-23 15:23:52