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For the determination of dissolved oxygen, working principle of the fiber optic oxygen sensor is studied. The sensor system calibration method and temperature compensation measures and their maintenance methods are analyzed. The dissolved oxygen sensors current widely using oxygen electrode and optical fiber oxygen sensor are compared. Optical fiber probe sensor is used in the current system, the multiple points and multiple samples can achieve the simultaneous detection.

Surface acoustic wave (SAW) devices are often used to monitor environmental parameters such as temperature, pressure or stress for instance. In order to ensure the continuity of the frequency response versus these parameters - namely, to remove the effects of directivity, transducers working out of the Bragg conditions are studied. In other words, the electrical excitation of the transducer is no more the usual alternating of one electrode set at a given potential with another one connected to the ground. This solution can be used either to preserve the spectral purity of the device or, on the contrary to enhance the multimodal nature of the acoustic cavity. Actually this paper shows that it can be exploited to design monolithic temperature SAW sensors.

This article describes the research and development directed toward an autonomous time-synchronized sensor device equipped with a chip scale atomic clock (CSAC) that records highly accurate time information. The R & D project presented herein aims to achieve earthquake observation to prepare for disasters and structural health monitoring to improve the efficiency of maintenance and management of buildings and civil engineering structures. For these reasons, it is necessary to install sensors in a wide area at a high density and to measure the data with accurately synchronized time information. It is recommended that the sensor device itself maintains accurate time information without relying on the network or a Global Positioning System (GPS) signal. Therefore, in this study, a sensor device that autonomously maintains accurate time information using an ultra-high precision, ultra- low power consuming, and ultra-small (and therefore, loadable on a board) atomic clock, known as CSAC, was developed. In this article, first, the concepts of autonomous time synchronization and CSACs are described, and the mechanism for assigning ultra- high precision time information to the sensor data by using a CSAC is explained. Next, the performance of the improved sensor device is demonstrated and the results of the vibration table test, which was conducted to examine the performance, are presented. Finally, the developed sensor devices were applied to an actual pedestrian bridge and acceleration measurement was carried out at several points on the bridge. The vibration characteristics of the bridge were obtained from a frequency analysis of the acceleration data.

The present study focuses on the production of bioelectricity through the use of microbial fuel cells (SMFC) using a pure culture of Pseudomonas aeruginosa extracted from Andean soils at 3850 m above sea level. This biosensor has been developed from cell systems of bioelectrochemical microbial fuels that are used for the control of toxic compounds such as nitrate. In the study two treatments were applied each with different concentration of NO3 - which were examined individually by microbial fuel cells in batches built from a single chamber partially exposed to air, at the end of the complete investigation of the analyzes presented the nitrate in each of the cells. According to the results obtained from bioelectricity. The bacterial culture of Pseudomonas spp. generates a considerable production of bioelectricity, a concentration of 30 mg/L in the microbial fuel cell 1 (SMFC1) produced 0.083 mV, and at 60 mg/L in the microbial fuel cell 2 (SMFC2) produced 0.109 mV, on average per day. This production increases proportionally if nitrate is added to the cells. With these findings, this system is proposed as a potential biosensor.

The results of computer simulation of heat distribution processes taking place after the absorption of single photons of 1 – 1000 eV energy in the three- layer detection pixel of the thermoelectric detector are being analyzed. Different geometries of the detection pixel with thermoelectric sensor made of strongly correlated semiconductor FeSb2, tungsten absorber and heat sink are considered. It is concluded that such detector may register individual photons from IR to X-ray providing energy resolution of not less than 1 % and terahertz counting rate.

Flood risk management and water resources planning involve a deep knowledge of surface streams so that mitigation strategies and climate change adaptations can be implemented. Commercially, there is a wide range of technologies for the measurement of hydroclimatic variables; however, many of these technologies may not be affordable for institutions with limited budgets. This paper has two main objectives: 1) Present the design of an ultrasound-based water level measurement system, and 2) Propose a methodological alternative for the development of instruments, according to the needs of institutions conducting monitoring of surface waterbodies. To that end, the proposed methodology is based on selection processes defined according to the specific needs of each waterbody. The prototype was tested in real-world scale, with the potential to obtain accurate measurements. Lastly, we present the design of the ultrasound-based water level measurement instrument, which can be built at a low cost. Low-cost instruments can potentially contribute to the sustainable instrumental autonomy of environmental entities and help define measurement and data transmission standards based on the specific requirements of the monitoring.

Three major carbon monoxide gas sensing technologies for combustion environment are reviewed with many theoretical and practical aspects, test results as well as basic operation details. A comprehensive CO gas sensing technologies review is supported with the latest development trends. Performance and applications options for carbon monoxide measurements in the process using calorimetric catalytic, mixed potential electrochemical CO-sensor with zirconia solid electrolyte and tunable diode laser (TDL) or quantum cascade lasers (QCL) spectroscopy for CO measurements are discussed for the applications in power generation, chemicals production, heating, process control, safety, and quality. Special attention is given to the technologies application limits and analyzer’s system requirements.

A simple design of a cholesterol concentration detection is proposed and demonstrated using a fiber optic displacement sensor based on an intensity modulation technique. The proposed sensor uses a bundled plastic optical fiber (POF) as a probe in conjunction with a flat mirror as a target. It is obtained that the peak voltage reduces with increasing cholesterol concentration. The sensor is capable of measuring the cholesterol concentration ranging from 0 to 300 ppm in a distilled water with a measured sensitivity of 0.01 mV/ppm, a linearity of more than 99.62 % and a resolution of 3.9188 ppm. The proposed sensor also shows a high degree of stability and good repeatability. The simplicity of design, accuracy, flexible dynamic range, and the low cost of fabrication are favorable attributes of the sensor and beneficial for real- field applications. Fiber optic sensors

This paper is a review of our works on implementation of measuring systems for two-phase helium, hydrogen, liquefied natural gas (LNG) and oil production. In principle, two-phase flow-meters combining void fraction radio-frequency (RF) sensors and narrowing devices are considered in details. In particular, they can be applied for superconducting accelerators cooled with two-phase helium, refueling hydrogen system for space ships and some applications in LNG production industry. To produce these cryogenic two-phase flow-meters it is necessary to combine such devices as low temperature sensors, cryogenic void fraction sensors, sensors responsive to average velocity of the two-phase flow, pressure sensors and electronics to measure their signals. The measuring systems for two-phase liquefied natural gas (LNG), and oil-formation/salty water flows are also presented. These systems are based on combination of a gamma-densitometer and a narrowing device. It is shown as well that the experience gained allows separationless flow-meter for three-phase oil-gas- formation water flows to be produced.

While entering the modern society, medical technology has been able to cure almost all kinds of diseases. However, autoimmune diseases are increasing rapidly due to environment, food, and indoor life. In particular, vitamin D is lacking in about 90 % of Koreans. As a result of this, many middle-aged and older women are taking calcium, but most of them do not know their vitamin D levels. Based on this background, the goal of this paper is to develop a vitamin D measurement technique using a quantum analyzer that is capable of measuring various kinds of vitamins and minerals, and to prepare a plan to easily measure vitamin D by attaching it to a UVB device that is currently used in the hospital. The quantum analyzer was designed based on the impedance principle, and the impedance change according to vitamin D concentration was able to confirm a significant proportional relationship between vitamin D and impedance. In addition, the correlation between vitamin D and impedance was confirmed by in vitro experiment using lab mice, and the measurement error of the impedance meter for vitamin D concentration in the blood was confirmed to be about 12.7 %.

Analysis at a cellular level is an integral aspect that gives a clear understanding of a single cell’s health condition as well as its internal metabolism. However, the field of genetics revealed nothing on single cell temperature analysis. In this paper, we proposed a noble technique for single cell temperature measurement using lead zirconate titanate (PZT) integrated microcapacitive sensor. The microcapacitive sensor has been modelled numerically and validated based on the current literatures. The sensor has been optimised by using parabolic geometry and integrated with PZT material for optimal separation between the sensor plates without having contact with the cell under investigation. The sensitivity of the PZT material integrated with the sensor was obtained as 0.0729 VmN-1. Similarly, Saccharomyces cerevisiae cell has been modelled numerically and validated based on compression test experiment and Kedem-Katchalsky constitutive equation for fluid flow in a cell. 11.0381±0.0057 Nm-1 and 108.9301±0.0084 MPa for stiffness and young’s modules were obtained respectively. The PZT-integrated microcapacitive sensor and the Saccharomyces cerevisiae cell have been assembled for non-invasive temperature measurement. 0.5416±3.5581×10-3 nF and 0.7582±5.1366×10-3 mFcm-2 were obtained for capacitance and dielectric constant value respectively for the Saccharomyces cerevisiae cell at normal atmospheric pressure which corresponds to 37 0C when a voltage of 1.0000 mV has been applied to the sensor. Saccharomyces cerevisiae cell dielectric constant of 1.5700×10-3±7.500×10-4 mFcm-2 has been obtained for each 5 0C change in temperature. Using the value above and interpolation technique the temperature of any single Saccharomyces cerevisiae cell can be obtained accurately. Temperature plays a vital role for characterising the health condition of the cell. In the future, the technique be a more effective and accurate supplement for the current biochemical method used disease diagnosis at cellular level.

Outstanding conductivity and biocompatibility of Carbon nanotube (CNT) and conducting polymer (CP) have shown the unparalleled superiorities in the area of electrochemical sensors. Emphasis has been given on the types of functionalization, fabrication of sensor, role of graphite, CNT and CP in environment monitoring and assay strategies. It is very important to develop a simple, effective, sensible, reliable and accurate method to detect heavy metals present in the environment as a pollutant. Other traditional or conventional methods like Atomic Absorption Spectrophotometer, Flame Photometer, Gravimetery etc. have their own limitations and disadvantages. We have fabricated novel graphite, CNT and CP (polyaniline) based amperometric sensor for the detection of Zinc metal as an environment pollutant. The electrochemical performance of amperometric sensor was tested by Cyclic Voltammetry, Ampereometry and Linear Sweep Voltammetry experiments. The developed amperometric sensor displays good electrochemical activity towards the detection of Zinc present in the environment. Storage and stability conditions were also tested.

In this study graphene oxide was functionalized by 2-(5-bromo-2- pyridylazo)-5-diethylaminophenol (5-Br-PADAP) and incorporated into a carbon paste electrode. This modified electrode was applied for determination of trace amount of cadmium (II). The analysis procedure is consist of three steps, firstly, an open circuit accumulation in stirred sample solution was occurred for 7 min. Cd2+ was accumulated on the surface of a modified Carbon paste electrode via forming Cd-5-Br- PADAP complex. This step was followed by medium exchange to a 0.1 mol L- 1 HCl solution, where the accumulated cadmium was reduced for 15 s at -1.10 V (vs. Ag/AgCl). Finally, cadmium was oxidized, and voltammograms were recorded by scanning the potential in a positive direction. The calibration plot was linear over the cadmium concentration range from 0.25-210 µg L-1. The detection limit was 9.7×10-2 µg L-1. Using this new modified carbon paste electrode, trace level of Cd2+ in water samples was determined.

We investigate molecular adsorption doping by electron withdrawing NO2 and electron donating NH3 on epitaxial graphene grown on C-face 6H-SiC substrates. We reconcile models describing the conductivity of graphene at low and high frequencies in the relaxation time approximation. These equations are applied to develop theoretical model for adsorption of NO2 and NH3 molecules on an epitaxial graphene surface probed by infrared reflectance, a non-destructive technique for transport studies in graphene. We separate the intraband and interband scattering contributions to the electronic transport under gas adsorption. We find that only by including a significant interband (intraband) contribution can measured reflectance be fit accurately at low (high) frequency regime. Interband relaxation times as short as ~0.1 fs are obtained under gas adsorption, much shorter than previously assumed (~100 fs), leading to a breaking of the usual universal conductivity observed in purer samples. This method can also calculate percentage charge transfer by NO2 to graphene (1~2 %) and NH3 to graphene (0.01~0.1 %). Finally, this transport behavior indicate that, under gas adsorption, the influence of interband scattering cannot be neglected, even at DC

In this paper, we present a novel system, inVideo, for automatically indexing and searching videos based on the keywords spoken in the audio track and the visual content of the video frames. Using the highly efficient video indexing engine we developed, inVideo is able to analyze videos using machine learning and pattern recognition without the need for initial viewing by a human. The time-stamped commenting and tagging features refine the accuracy of search results. The cloud-based implementation makes it possible to conduct elastic search, augmented search, and data analytics. Our research shows that inVideo presents an efficient tool in processing and analyzing videos and increasing interactions in video-based online learning environment. Data from a cybersecurity program with more than 500 students show that applying inVideo to current video material, interactions between student-student and student-faculty increased significantly across 24 sections program-wide.

As new as very promising technique, breath analysis allows for monitoring the biochemical processes that occur in human body in a non-invasive way. Nevertheless, the high costs for standard analytical instrumentation (i.e., gas chromatograph, mass spectrometer), the need for specialized personnel able to read the results and the lack of protocols to collect breath samples, set limit to the exploitation of breath analysis in clinical practice. Here, we describe the development of a device, named Wize Sniffer, which is portable and entirely based on low cost technology: it uses an array of commercial, semiconductor gas sensors and a widely employed open source controller, an Arduino Mega2560 with Ethernet module. In addition, it is very easy-to-use also for non-specialized personnel and able to analyze in real time the composition of the breath. The Wize Sniffer is composed of three modules: signal measurement module, signal conditioning module and signal processing module. The idea was born in the framework of European SEMEiotic Oriented Technology for Individual's CardiOmetabolic risk self-assessmeNt and Self-monitoring (SEMEOTICONS) Project, in order to monitor individual's lifestyle by detecting in the breath those molecules related to the noxious habits for cardio-metabolic risk (alcohol intake, smoking, wrong diet). Nonetheless, the modular configuration of the device allows for changing the sensors according to the molecules to be detected, thus fully exploiting the potential of breath analysis.

In 1974, H. L. Resnkikoff published an inspiring paper about the use of differential geometry to study, among others, the intrinsic shape of the space of perceived colors and the Riemannian metrics on it. The mathematical techniques that he used is shared with modern theories of theoretical physics, which are far from being a common background for scientists in color vision and processing. Due to this, Resnikoff’s paper remained unnoticed for decades. In this brief contribution, some insights about how to update Resnikoff’s ideas will be given and discussed in relationship with a modern theory of color spaces and to the mathematical concept of principal fiber bundle.

Active contour models are designed to evolve an initial curve, called level set, to extract the desired object(s) in an image. Most approaches are based on semi-implicit schemes which are stable for all time steps. Various models are used for the global segmentation such as Chan-Vese (CV) model. The CV model has the global segmentation property to segment all objects in an image. The problem with this model is the high time computing. In order to reduce it, our contribution in this work is the association of a semi-implicit Additive Operator Splitting (AOS) technique with the CV model in biphase and multiphase cases. The basic idea behind AOS schemes is to decompose a multi-dimensional problem into one-dimensional ones that can be solved very efficiently. In this paper, we present the new association in biphase and multiphase cases with simulations showing the efficiency of the proposed method.

This review discusses on Quartz Crystal Microbalance (QCM) and microfluidic driven by ultrasonic acoustic forces, as possible alternative technologies to develop compact and portable diagnostic point of care (POC). Extension of QCM to measure 10-15 g/cm2 is possible and development of this technology will open up new business opportunities in public health, life sciences, and material sciences. The experimental results showed that QCM technology can be 1000 times more sensitive, than the currently available mass sensor systems in the market. The target market is on diagnostic POC, focussing on home care, public health, and agriculture and food industry sectors. Some of the challenges discussed are: 1) A centrifuge for blood plasma separation (BPS), and 2) Microfluidic driven by ultrasonic acoustic forces, for separation of suspended particles in the whole blood. We also present an overview of the expected global market growth from 2011 to 2020 and the benefits to the end users.

The features of constructing of a linear displacement measurer with differential capacitive transducer are considered. The measuring circuit is analyzed, which makes possible to implement a linear algorithm for determining the measured displacement. With an appropriate choice of the base element, in the production conditions the device can provide measurement of linear displacements with a limit of the permissible basic comparative error not exceeding 0.12 %.

The synthetic material, cadmium sulfide quantum dot particles (CdSQD), using a hydrothermal method was dispersed in poly methyl methacrylate (PMM) polymer. In order to study the synthesized quantum dot particles, X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) techniques were applied. Transmission electron microscopy (TEM) and scanning electron microscopy (SEM) images were also used to study the surface morphology of synthetic quantum dot particles. Energy-dispersive X-ray spectroscopy (EDX) test was done for identification of constituent percent of prepared material. Optical properties of CdSQD particles were evaluated by UV-visible and photoluminescence spectroscopy (PL). Finally the capability of CdSQD particles dispersed in poly methyl methacrylate (CdSQD@PMM) as a scintillator material was investigated by photomultiplier tube (PMT) test. The result of PMT test along with statistical studies showed that the CdSQD@PMM can be applied as a crystalline promising material in the field of inorganic scintillator detectors regarding to the efficiency and economic aspects.

Electrochemical sensors can be used for a wide range of online in- situ process monitoring applications. However, the lack of a consistent electrolyte layer has previously limited electrochemical monitoring in gas and supercritical fluid streams. A solid state sensor is being designed that uses an ion conducting membrane to perform conductivity and corrosion measurements in natural gas pipelines up to 1000 psi. Initial results show that membrane conductivity measurements can be correlated directly to water content down to dew points of 1°C with good linearity. Corrosion monitoring can also be performed using methods such as linear polarization resistance and electrochemical impedance spectroscopy (EIS), though care must be taken in the electrode design to minimize deviation between sensors.

Matrix Matelloproteinase-2 (MMP-2) plays a key role in many diseases. A new type of dual-functioning device was developed for fast, direct ultrasensitive detection of MMP-2. We report a memristive/memcapacitive device with vertex double-helical polarized biomimetic protein nanotubules forming double membranes with potential gradient mimicking mitochondria’s inner double membrane has developed. We also report Fermi arcs with nodes on the surface of the nanostructured membrane was observed at the first time by using a 3D real-time - energy-current dynamic mapping method based on data obtained from the Cyclic Voltammetry (CV) method. The memristive/memcapacitive device comprises a cross- linked organic polymer having single-wall cross-bar polarized nanotube self-assembling membrane (SAM) on a gold chip, under an applied potential, a pair of vertex double- helical circular current flow induced the Fermi arcs states occurrence and these Fermi arcs promoted a direct chelating with zinc ions of the MMP-2 to become possible without any antibody, tracer, or reagent used at room temperature was accomplished. We observed the pair of Dirac Cones became alignment and strengthened with each other in the presence of MMP-2 compared without MMP-2. The MMP-2 can be detected with ag/mL level sensitivity and the value of Detection of Limits (DOL) reached orders of magnitude lower than published reports with simplified procedures by a Chronoamperometry (CA) method and a Double Step Chronopotentiometry (DSCPO) method using NIST SRM 965A standard human serum, respectively. The results show a feasible application for developing the commercial fast and real-time MMP monitoring devices for various diseases.

This paper presents a neural network method to model nanometer FinFET performance. The principle of this method is firstly introduced and its application in modeling DC and conductance characteristics of nanoscale FinFET transistor is demonstrated in detail. It is shown that this method does not need parameter extraction routine while its prediction of the transistor performance has a small relative error within 1 % compared with measured data, thus this new method is as accurate as the physics based surface potential model.

Monitoring carbon sequestration poses numerous challenges to the sensor community. For example, the subsurface environment is notoriously harsh, with large potential mechanical, thermal, and chemical stresses, making long-term stability and survival a challenge to any potential in situ monitoring method. Laser induced breakdown spectroscopy (LIBS) has been demonstrated as a promising technology for chemical monitoring of harsh environments and hard to reach places. LIBS has a real- time monitoring capability and can be used for the elemental and isotopic analysis of solid, liquid, and gas samples. The flexibility of the probe design and the use of fiber- optics has made LIBS particularly suited for remote measurements. The paper focuses on developing a LIBS instrument for downhole high-pressure, high-temperature brine experiments, where CO2 leakage could result in changes in the trace mineral composition of an aquifer. The progress in fabricating a compact, robust, and simple LIBS sensor for widespread subsurface leak detection is presented.

A dual self-powered biosensing system integrated with energy amplification circuit is described, for simultaneously monitoring glucose and lactate. The self-powered biosensing system is based on the conventional enzymatic biofuel cell equipped with three 4 mm x 4 mm massively dense mesh network of multi-walled carbon nanotubes (MWCNTs) bioelectrodes in parallel configuration. The bioelectrodes employed pyroquinoline quinone glucose dehydrogenase (PQQ-GDH) as the biocatalyst for the glucose oxidation and D-Lactate dehydrogenase (D-LDH) as the biocatalyst for lactate oxidation. A common laccase modified-MWCNTs bioelectrode served as the cathode for the reduction of molecular oxygen. Two charge pump circuits were coupled with 0.1 mF capacitors functioning as transducers. The advantages of employing capacitors were coupled with the efficient energy amplification of the charge pump circuit to amplify the power output from each of the biofuel and charge/discharge the corresponding capacitor. Under operating conditions, the open circuit voltages and short circuit current densities for 180 mg/dL glucose and 25 mM lactate were 339.2 mV and 228.75 µA/cm2 and 370 mV and 66.17 µA/cm2, respectively. The responses for glucose and lactate were linear up to 630 mg/dL and 30 mM with sensitivities of 20.11 Hz/ mM cm-2 and 9.869 Hz/ mM cm-2, respectively. The potential of the described system was demonstrated to provide stable voltage and current output that was capable of driving the charge pump circuit integrated with the capacitor for simultaneously monitoring glucose and lactate. These results were in good agreement with those previously reported.

The main approaches of parametric analysis of impedance measuring transducers on the base of SPICE modeling are considered in paper. In the modeling process, the galvanostatic measurement method is used, which is on the base of the determination of the ratio and phase delay between the voltage and the harmonic current with the specified amplitude and frequency. As a result of simulation, the possibility of significant increase of the measurement transformation accuracy is found by means of modifying the input circuits of the impedance measuring transducers.

The recent geo-political climate has increased the necessity for autonomous, chip-sized, lightweight, air sampling systems which can quickly detect and characterize chemical, biological, radiological, nuclear, and high explosive (CBRNE) hazardous materials and relay the results. To address these issues, we have developed a self-powered 3-D chip architecture that processes air to produce concentrated size- sorted particle (and vapor) samples that could be integrated with on-chip nanoelectronic detectors for the discovery of weapons of mass destruction (WMD). The unique air movement approach is composed of a nanoscale energy harvester that provides electricity to a printed ion-drag pump to push air through coated-microstructured arrays. The self-powered microstructured array air sampler was designed using computational fluid dynamics (CFD) modeling to collect particles from 1-10 microns at greater than 99.9999 % efficiency with less than 100 Pascal [Pa] pressure drop at a specified air flow rate. Surprisingly, even at minimum air flow rates below specifications, these CFD predictions were matched by experimental results gathered in a Government aerosol chamber. The microstructured array engineered filter equaled the collection capability of a membrane or a high efficiency particle air (HEPA) filter at a fraction of the filter pressure drop.

Most of the cancers are curable if they are detected at early stages. The early stage detection of cancers can significantly improve the patient treatment outcomes and thus helps to decrease the. To achieve the early detection of specific cancer, the biochip is incorporated with an innovative sensing mechanism and surface treated microchannels. The sensing mechanism employed in the Point of Care (POC) biochip is designed to be highly specific and sensitive. The surface treated microchannel helps to control the self-driven flow of the blood sample. Cancer antibodies with enhanced specificity and affinity are immobilized on the surface of the nano circuit in the microchannel. When the blood sample flows in the microchannel over the cancer antibodies, the corresponding cancer antigens from the blood form the antigen-antibody complex. These antigen-antibody interactions are captured with the variation in the electrical properties of the gold nano circuit using the sensing mechanism in the biochip. The point of care (POC) micro biochip is designed as an in- situ standalone device to diagnose ovarian cancer at the early stages by sensing the cancer antigens in the blood sample drawn from a finger prick. The POC biochip can help to diagnose, the existence of cancer and also its severity using the qualitative and the quantitative results of the sensing mechanism in the biochip.

Electro-optic infrared technologies and systems operating from ultraviolet (UV) to long-wave infrared (LWIR) spectra are being developed for a variety of defense and commercial systems applications. Loss of a significant portion of the incident signal due to reflection limits the performance of electro-optic infrared (IR) sensing systems. A critical technology being developed to overcome this limitation and enhance the performance of sensing systems is advanced antireflection (AR) coatings. Magnolia is actively involved in the development and advancement of nanostructured AR coatings for a wide variety of defense and commercial applications. Ultrahigh AR performance has been demonstrated for UV to LWIR spectral bands on various substrates. The AR coatings enhance the optical transmission through optical components and devices by significantly minimizing reflection losses, a substantial improvement over conventional thin-film AR coating technologies. Nanostructured AR coatings have been fabricated using a nanomanufacturable self-assembly process on substrates that are transparent for a given spectrum of interest ranging from UV to LWIR. The nanostructured multilayer structures have been designed, developed and optimized for various optoelectronic applications. The optical properties of optical components and sensor substrates coated with AR structures have been measured and the process parameters fine-tuned to achieve a predicted high level of performance. In this paper, we review our latest work on high quality nanostructure-based AR coatings, including recent efforts on the development of nanostructured AR coatings on IR substrates.

In the advanced CMOS process lines, the process-induced stress is often used to increase carrier mobility so as to improve MOSFET performance. It also strongly affects the carrier mobility of T-FinFET as long as it is fabricated with the CMOS process as always done in experiment tunneling FET device. Here we report the effect of process-induced stress on mobility enhancement and a corresponding compact model. The layout dependence of T-FinFET’s carrier mobility due to process-induced stress is efficiently captured. The mobility model is verified for different layout dimensions for several stress-inducing process technologies through both process simulations and experimental data.

peer-reviewed The system described in this work is a variant from traditional acoustic levitation first described by, Marzo et al [1]. It uses multiple transducers eliminating the requirement for a mirror surface, allowing for an open geometry as the sound from multiple transducers combines to generate the acoustic trap which is configured to catch pico litres of crystal slurries. These acoustic traps also have the significant benefit of eliminating potential beam attenuation due to support structures or microfluidic devices. Additionally they meet the need to eliminate sample environments when experiments are carried out using an X-ray Free Electron Lasers (XFEL) such as the Linac Coherent Light Source (LCLS) as any sample environment would not survive the exposure to the X-Ray beam. XFELs generate Light a billion times brighter than the sun. The application for this system will be to examine turn over in Beta lactamase proteins which is responsible for bacteria developing antibiotic resistance and therefore of significant importance to future world health. The system will allow for diffraction data to be collected before and after turnover allowing for a better understanding of the underling processes. The authors first described this work at Nanotech 2017 [2].

Solid-state sensors made from doped metal oxide ZnO and SnO2 were prepared for detection of hydrogen peroxide vapours. Gas sensitive nanostructured films were manufactured by the high-frequency magnetron sputtering method. Thicknesses of deposited semiconductor nanostructured films were measured and its morphology was investigated. The average size of nanoparticles was equal to 18.7 nm for deposited films. The response of the prepared sensors was measured at different temperatures of the sensor work body and different concentrations of hydrogen peroxide vapours. It was found that both La-doped ZnO and Co-doped SnO2 sensors exhibit a sufficient sensitivity to 10 ppm of hydrogen peroxide vapours at the operating temperature 220 °C and 200 °C, respectively. It was established that the dependencies of the sensor sensitivity on hydrogen peroxide vapours concentration at the work body temperature 150 °C have a linear characteristic for both prepared structures and can be used for determination of hydrogen peroxide vapours concentration.

Citrus tristeza is one of the most important diseases of citrus in the world. To avoid the destructive effect of the disease, early detection of infected plants is crucial. Therefore, simple and sensitive diagnosis tools are decisive. The main objective of the present study was developing nanobiosensors for detection of citrus tristeza based on the florescence emission of cadmium telluride quantum dots (CdTe-QDs). To achieve that, CdTe-QD particles were initially synthesized and effectively conjugated to CTV coat protein (CTV-CP) corresponding antibody. In a parallel reaction, rhodamine dye molecules were attached to the purified recombinant CTV-CP. Two independent approaches were explored for detection of the infected plants. First, in a fluorescence resonance energy transfer (FRET) based assay, the quenching ability of rhodamine molecules was applied for altering the QDs light emission. More specifically, donor- acceptor complexes (Ab-QD+CP-Rd) were created based on the affinity of antibody- antigen molecules. The resulting assembly brought Ab-QD (the donor) and the Rd-CP (the acceptor) into a close proximity and resulted in a substantial decrease in the intensity of QD light emission. Addition of free antigen into the solution resulted in the replacement of CP-Rd with free CP and a subsequent increase in the emission of QDs. In the second approach, a non-FRET based assay was performed through the addition of free antigen to the Ab-QD solution, which led to the aggregation of the Ab-QD conjugates and consequently a significant increase in the light intensity emission of the QD. To the best of our knowledge, this is the first time that the non-FRET based assay developed herein is being reported.

Prolonged monitoring is more likely to diagnose atrial fibrillation accurately than intermittent or short-term monitoring. In this study, an implantable electrocardiograph (ECG) sensor to monitor atrial fibrillation patients in real time was developed. The implantable sensor is composed of a micro controller unit, an analog-to-digital converter, a signal transmitter, an antenna, and two electrodes. The sensor detects ECG signals from the two electrodes and transmits these to an external receiver carried by the patient. Because the sensor continuously transmits signals, its battery consumption rate is extremely high; therefore, the sensor includes a wireless power transmission module that allows it to charge wirelessly from an external power source. The integrated sensor has the approximate dimensions 0.12 in × 1.18 in × 0.19 in, which is small enough to be inserted into a patient without the need for major surgery. The signal and power transmission data sampling rate and frequency of the unit are 300 samples/s and 430 Hz, respectively. To validate the developed sensor, experiments were conducted on small animals.

In this paper, power and speed efficient registers have been designed using different nanometer technologies. Serial in Serial out (SISO) and Serial in Parallel out (SIPO) shift registers are designed using 180 nm and 90 nm technologies. Both the design are analyzed and compared based on power, delay and power-delay-product (PDP). Present portable real time system demands high performance in terms of speed along with low power consumption. The concept of technology scale down has been used to optimize power and delay in booth designs. The schematic of SISO and SIPO has been developed using Cadence Virtuoso software and analysis has been performed using Analog Design Environment. It has been observed from simulation analysis that 90 nm based SISO design shows an improvement of 68.61 % in power and 54.92 % in delay as compared to 180 nm technology. Likewise SIPO design has shown an improvement of 67.75 % in power and 53.32 % in delay as compared to 180 nm technology.

Wireless sensor networks face significant design challenges due to limited computing and storage capacities and, most importantly, dependence on limited battery power. Energy is a critical resource and is often an important issue to the deployment of sensor applications that claim to be omnipresent in the world of future. Thus optimizing the deployment of sensors becomes a major constraint in the design and implementation of a WSN in order to ensure better network operations. In wireless networking, clustering techniques add scalability, reduce the computation complexity of routing protocols, allow data aggregation and then enhance the network performance. The well-known MaxMin clustering algorithm was previously generalized, corrected and validated. Then, in a previous work we have improved MaxMin by proposing a Single- node Cluster Reduction (SNCR) mechanism which eliminates single-node clusters and then improve energy efficiency. In this paper, we show that MaxMin, because of its original pathological case, does not support the grid deployment topology, which is frequently used in WSN architectures. The unreliability feature of the wireless links could have negative impacts on Link Quality Indicator (LQI) based clustering protocols. So, in the second part of this paper we show how our distributed Link Quality based d- Clustering Protocol (LQI-DCP) has good performance in both stable and high unreliable link environments. Finally, performance evaluation results also show that LQI-DCP fully supports the grid deployment topology and is more energy efficient than MaxMin.

We present results of our research works related to the study of thick-film multiwall carbon nanotube/tin oxide nanocomposite sensors of propylene glycol (PG), dimethylformamide (DMF) and formaldehyde (FA) vapors derived using hydrothermal synthesis and sol-gel methods. Investigations of response/recovery characteristics in the 50-300 oC operating temperature range reveal that the optimal operating temperature for PG, DMF and FA vapor sensors, taking into account both high response and acceptable response and recovery times, are about 200 and 220 oC, respectively. A sensor response dependence on gas concentration in all cases is linear. The minimal propylene glycol and dimethylformamide gas concentrations at which the perceptible signal was registered by us were 13 ppm and 5 ppm, respectively.

Wireless Sensor Network (WSN) is one of the most dominant technology trends in the upcoming decades. Due to the lack of communication infrastructure, designing a WSN has posed a real challenge to the designers. WSNs should capture information from the environment, acquired, receive and retransmit them while having enough lifetime to reach many decades without external intervention. Thus, optimizing some objective functions, like energy consumption and coverage at the levels of nodes deployment is required to enhance the performances. In this work, deployment issue has been modeled as a constrained multi-objective optimization (MOO) problem. The aim of this work was to find the optimal sensor nodes positions in the area of interest in terms of coverage, energy consumption and network connectivity. A new multi-objective optimization approach based on Flower Pollination Algorithm (FPA) was introduced. The simulation results show that the proposed approach improve both coverage and energy consumption compared with other multi objective approaches.

In pet food production, the development of new products must take into account both nutritional and palatability aspects. Pet food palatability is related to the pet food sensory properties, such as aroma, flavour, texture shape, and particle size. The pet food industry may take advantage of a sensorial analysis as a powerful tool for quality control and management. The objective of this idea is to set up an electronic nose (e-nose) and tongue (e-tongue) as rapid quality control and research & development tools for the pet food industry. The final goal is to integrate e-nose and e- tongue with other sensing and imaging devices to 1) Ensure high pet food standards in terms of nutritional properties, palatability and acceptability; 2) Set up an instrumental protocol with good correlation to animal sensory properties in order to replace animal preference test, chemical and texture analysis.

One of the most significant problems in Wireless Sensor Network (WSN) deployment is the generation of topologies that maximize transmission reliability and guarantee network connectivity while also maximizing the network’s lifetime. Transmission power settings have a large impact on the aforementioned factors. Increasing transmission power to provide coverage is the intuitive solution yet with it may come with lower packet reception and shorter network lifetime. However, decreasing the transmission power may result in the network being disconnected. To balance these trade-offs we propose a discrete strategy game-theoretic solution, which we call TopGame that aims to maximize the reliability between nodes while using the most appropriate level of transmission power that guarantees connectivity. In this paper, we provide the conditions for the convergence of our algorithm to a pure Nash equilibrium as well as experimental results. Here we show, using the Indriya WSN testbed, that TopGame is more energy-efficient and approaches a similar packet reception ratio with the current closest state of the art protocol ART. Finally, we provide a methodology for further optimization of our work using an indicator function to distinguish between satisfactory and poor links.

Key management is an essential functionality for a security protocol; particularly for implementations to low cost devices of a distributed sensor networks (DSN)–a prototype of Internet of Things (IoT). Constraints in resources of the constituent devices of a low cost IoT (sensors of DSN) restricts implementations of computationally heavy public key cryptosystems. This led to adaptation of the novel key predistribution technique in symmetric key platform to efficiently tackle the problem of key management for these resource starved networks. Initial proposals use random graphs, later key predistribution schemes (KPS) exploit combinatorial approaches to assure essential design properties. Combinatorial designs like a (v, b, r, k)– configuration which forms a µ–CID are effective schemes to design KPS. A net in a vector space is a set of cosets of certain kind of subspaces called partial spread. A µ(v, b, r, k)–CID can be formed from a net. In this paper, we propose a key predistribution scheme for DSN, named as Sensornet, using a net. We observe that any deterministic KPS suffer from “smart attack” and hence devise a generic method to eliminate it. Resilience of a KPS can be improved by clever Hash Chains technique introduced by Bechkit et al. We improve our Sensornet to achieve Hash Chains Sensornet (HC(Sensornet)) by the applications of these two generic methods. Effectiveness of Sensornet and HC(Sensornet) in term of crucial metrics in comparison to other prominent schemes has been theoretically established.

We have synthesized and used several natural dyes such as extracted from: Spinach, Beet, Henna, Strawberry, Red cabbage, and Mloukhia. The absorption of the extracted dyes diluted in ethanol or distilled water were measured using UV–Vis spectrophotometer. We have studied the topology of these films by scanning electron microscope (SEM), X-ray photoelectron spectroscopy (XPS) and x-ray diffraction (XRD) patterns of synthesized TiO2. The contents of Ti and O of synthesized TiO2 are 30 % and 50 % corresponding to closely Ti4+ state. The absorption of the TiO2 thin films immersed in these dyes was also measured in order to tune the change. The absorption in Beet and Red cabbage is more significant compared to other natural dyes.

We design, implement, and test a novel tactile elasticity imaging sensor to detect the elastic modulus of a contacted object. Emulating a human finger, a multi-layer polydimethylsiloxane waveguide has been fabricated as the sensing probe. The light is illuminated under the critical angle to totally reflect within the flexible and transparent waveguide. When a waveguide is compressed by an object, the contact area of the waveguide deforms and causes the light to scatter. The scattered light is captured by a high resolution camera. Multiple images are taken from slightly different loading values. The distributed forces have been estimated using the integrated pixel values of diffused lights. The displacements of the contacted object deformation have been estimated by matching the series of tactile images. For this purpose, a novel pattern matching algorithm is developed. The salient feature of this sensor is that it is capable of measuring the absolute elastic modulus value of soft materials without additional measurement units. The measurements were validated by comparing the measured elasticity of the commercial rubber samples with the known elasticity. The evaluation results showed that this type of sensor can measure elasticity within ±5.38 %.

Nanocrystalline a-Fe2O3 powder was synthesized by simple, inexpensive sol-gel method. The obtained powder was calcined at 700 0C in air atmosphere for 2 hours. The structural and morphological properties of calcined powder were studied by X-ray diffraction (XRD) and Field Emission Scanning Electron Microscopy (FESEM) respectively. Thermal properties of dried gel were studied by Thermogravimetric Analysis/Differential Scanning Calorimetry (TGA/DSC). The XRD pattern of the powder confirmed the a-Fe2O3 (hematite) phase of iron oxide with average crystalline size of 30.87 nm calculated from Scherrer equation. The FESEM images showed uniform wormlike morphology of a-Fe2O3 powder. TGA result indicated that a-Fe2O3 is thermodynamically stable. Room temperature NH3 sensing characteristics of a-Fe2O3 were studied for various concentration levels (250-2500 ppm) of NH3 at various humid conditions. The sensor based on a-Fe2O3 exhibited good selectivity and excellent sensitivity (S=92) towards 1000 ppm of NH3 with quick response of 4 sec and fast recovery of 9 sec. Room temperature sensing mechanism is also discussed.

Routing protocols heavily influenced by the node motion applied. Many performance analyses are already done with a lot of flaws. But, they do not look to all influenced constraints. Sometimes, they evaluate routing protocols without taken into consideration mobility models. They often analyze them using one routing protocol. Whereas, Simulation time employed is too short. It mainly impacts performance metrics of many mobility models. Or usually, simulation area used is small. It influences the number of packets received. In this study, we aim to summarize all these several parameters into 90 different scenarios with an average of 1350 simulated files. We will combine some well-known mobility models with the most prominent mobile Ad hoc routing protocols in order to analyze their accurate behaviors in one experimental synthesis paper. That shows results of three performance metrics combined with five mobile ad hoc routing protocols under three synthetic mobility models. All these parameters are applied to two dissimilar simulation areas, a small one with (220 m x 220 m) and a large one with (1020 m x 1020 m). Basing on one exhaustive analysis with all these details like this paper; leads to well understand the accurate behaviors of routing protocols and mobility models used. By displaying the ability of every routing protocol to deal with some topology changes, as well as to ensure network performances.

There has been given the solution of the technical problem of separate measurement of parameters of inductance coils and inductive primary converters on alternating current without application of potential-current signals. As a measuring circuit the scheme of voltage divider with active-inductive two-pole is used, and as an output signal there has been used the angle of phase shift between two output voltages of the measuring circuit. For forming the output signal temporal separation of measurement channel is used. The advantages of phase method are mostly due to capacity of using microcontrollers. In the technical solutions under consideration the microcontroller regulates the measuring process and develops the measurement results.

SnO2 based sensing nano-material have been synthesized by simple chemical route using Stannic (IV) chloride-pentahydrate (SnCl4.5H2O) as precursor. The structural properties of the prepared SnO2 nano-particles annealed at different temperatures have been characterized by X-ray diffraction (XRD) analysis. The XRD patterns showed pure bulk SnO2 with a tetragonal rutile structure in the nano-powders. By increasing the annealing temperatures, the size of crystals were seen to increase, the diffraction peaks were found narrower and the intensity was higher. SnO2 films prepared by spin coating the prepared nano-material solution was tested at different temperatures for methanol vapour and it showed that the film prepared from SnO2 powder annealed at 500 0C shows the higher sensitivity to methanol vapour at 150 0C substrate temperature with significantly low response and recovery time.

It was developed an amperometric biosensor to determine tungsten in water, based on the inhibition of laccase enzyme, by tungsten ions using pyrocathecol as a substrate. The enzyme was immobilized with a proper mixture containing, bovine serum albumin, and glutaraldehyde, for a cross-linking process over screen-printed carbon electrodes, previously modified with tetrathiafulvalen and gold nanoparticles. Optimized experimental conditions are: pyrocatechol in cell 0.040 mM in a phosphate buffer pH 6.5 and applied potential +350 mV. The repeatability and reproducibility, in terms of relative standard deviation values, of de developed biosensor were 3.3 % (n=3), and 2.2 % (n = 5) respectively, and detection limit was 1.8 × 10-7 mol L-1. Additionally it was determined the kinetics of the systems by means of Michaelis-Menten Km apparent constants, calculated using Lineweaver-Burk plots, with and without tungsten. Kinetic study resembles to be competitive inhibition. A recovery study was performed with spiked blanks with a tungsten certified reference standard, traceable to NIST, giving as a result 102.3 ± 6.7 %; tap water samples analyzed presented a mean concentration of 1.75 µM, and recovery of the tungsten certified reference standard on the tap water samples gave 98.8 ± 3.1 %. Universidad de Costa Rica/[804-B5-164]/UCR/Costa Rica UCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Básicas::Centro de Investigación en Electroquímica y Energía Química (CELEQ)

The electrocardiogram (ECG) signal is widely used as one of the most important for analysis of cardiac condition of patients. It is necessary to filter the non-stationary noise from source to find clean ECG. This work falls within the overall framework of digital processing of the physiological signal. AT first data driven EMD method is chosen to get the IMFS and these IMFS further passed though DWT for filtration. To achieve the adaptive filtering process better further optimal threshold is calculated based on cultural algorithm. Denoising is performed on MIT-BIH database and evaluated with parameter called SER, MSE, and cross correlation. It is found that the hybrid algorithm EMD + DWT + Cultural based yield better results than traditional methods.