NASA's Kennedy Space Cenler (KSC) recently acquired two state-of-the-art wireless sensor systems as the final deli verable ora Phase " Small Business Technology Transfer (STIR) contract with Mnemonics, tnc. and the Uni versity of Central Florida (UCF), contract number NNX09CB69C. Mnemonics constnlcted the radio freq uency (RF) interrogator portion of these systems and UCF constructed the sensors, which arc based on a novel surface acoustic wave (SA W) arch itecture. The purpose of this testing is to characterize the performance of the system, both in its basic parameters and under a range of operat ing conditions.

关键词：传感器；信号探测器；声波；声表面波器件；变送器接收器

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In this project, intensive research effort has been invested in the development of self-powered MNSs, and various prototypes have been built up. Flexible piezotronic device based on RF-sputtered piezoelectric ZnO thin film is a great UV sensor. A nanogenerator based on the hydrothermal growth of a ZnO nanowire film on a spring shows a stable output and both the output voltage and current, displaying a linear relationship with the weight loaded on the spring. Thus, the nanogenerator can be utilized as an active mechanical sensor for measuring the weight applied onto the spring. A flexible thermoelectric nanogenerator (TENG) can be used as a wearable energy harvester by using human body temperature as the energy source. At the same time, the TENG can work as a self-powered temperature sensor with a response time of 17 s and a reset time of 9 s. The detection sensitivity of the sensor can reach 0.15 K in ambient atmosphere. The single output peak from a pyroelectric nanogenerator (PENG) based on a lead zirconate titanate (PZT) film can be used to directly drive a LCD. Further, a homemade Li-ion battery can be charged by the PENG under different working frequencies from 0.005 to 0.02 Hz, which can be used to drive a green LED. An integrated module in the form of a combination of a nanoparticle-WO3 film electrochromic device and a nanogenerator demonstrates the potential of monochrome self-powered displays. This self-powered electrochromic device showed desirable electrochromic response times and high coloration efficiency values. A transparent flexible nanogenerators made by growing ZnO nanowires on flexible polydimethylsiloxane (PDMS) substrate is a self-powered sensor for monitoring vehicle speed and detecting vehicle weight. Using two kinds of piezoelectric material, ZnO and poly-(vinylidene fluoride) (PVDF), we fabricate a composite structure for a nanogenerator (NG) or active- sensor for mechanical energy harvesting and vortex-based gas/liquid flow measurements.

关键词：传感器；能量收集；纳米技术；能源转换

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eLine, a class of multichannel time-variant integrating front-end Application Specific Integrated Circuits (ASICs), has been completed at SLAC National Accelerator Laboratory for applications at the Linac Coherent Light Source (LCLS). The class, designed for pixelated sensors with column parallel readout, is composed of two front-end ASICs: one designed for high-dynamic range applications (eLine10k) and one designed for ultra-low noise applications (eLine100). The first allows large input full-scale signals, on the order of 104 8keV photons, with a resolution of half a photon FWHM; while the second provides low noise charge integration, up to a full-scale signal of 100 8keV photons, with an equivalent noise charge (ENC) of 55e- r.m.s. Three different prototype systems utilizing the ASICs are described. The first is a 32k-pixel X-ray Active Matrix Pixel Sensor (XAMPS) detector developed at Brookhaven National Laboratory (BNL) for the X-ray Pump Probe instrument (XPP) at LCLS. The XAMPS are monolithic detectors with fast-frame readout and large full-scale signal. In particular, they provide a full well capacity on the order of 104 8keV photons per pixel and a resolution of half a photon FWHM. The second prototype, developed around eLine10k, is a beam finder with high dynamic range. The third prototype is developed around eLine100 to be used as detector in a spectrometer. Applications, test results and performance are discussed.

关键词：传感器；集成电路；探测器；直线加速器相干光源

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Flight measurement is a critical phase in development, validation and certification processes of technologies destined for future civilian and military operational capabilities. This paper focuses on several recent NASA-sponsored remote observations that have provided unique engineering and scientific insights of reentry vehicle flight phenomenology and performance that could not necessarily be obtained with more traditional instrumentation methods such as onboard discrete surface sensors. The missions highlighted include multiple spatially-resolved infrared observations of the NASA Space Shuttle Orbiter during hypersonic reentry from 2009 to 2011, and emission spectroscopy of comparatively small-sized sample return capsules returning from exploration missions. Emphasis has been placed upon identifying the challenges associated with these remote sensing missions with focus on end-to-end aspects that include the initial science objective, selection of the appropriate imaging platform and instrumentation suite, target flight path analysis and acquisition strategy, pre-mission simulations to optimize sensor configuration, logistics and communications during the actual observation. Explored are collaborative opportunities and technology investments required to develop a next-generation quantitative imaging system (i.e., an intelligent sensor and platform) with greater capability, which could more affordably support cross cutting civilian and military flight test needs.

关键词：传感器；天飞机轨道器；成像技术；飞行试验

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A Wheel Electrostatic Spectrometer has been developed as a surveying tool to be incorporated into a planetary rover design. Electrostatic sensors with various protruding cover insulators are embedded into a prototype rover wheel. When these insulators come into contact with a surface, a charge develops on the cover insulator through tribocharging. A charge spectrum is created by analyzing the accumulated charge on each of the dissimilar cover insulators. We eventually intend to prove charge spectra can be used to determine differences in planetary regolith properties. We tested the effects of residual surface charge on the cover insulators and discovered a need to discharge the sensor cover insulators after each revolution. We proved the repeatability of the measurements for this sensor package and found that the sensor repeatability lies within one standard deviation of the noise in the signal.

关键词：传感器；静电学；光谱仪；绝缘子

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This project, sponsored by the US Department of Energy (DOE) Nuclear Energy Enabling Technology (NEET) program, focuses on the development of advanced embedded sensors and controls to achieve significant performance, reliability, and safety improvements for nuclear reactor components and systems. As survivability and reliability are critical, designing and validating embedded measurement and control technologies in representative operating conditions are needed. With this framework in mind, a canned rotor pump platform is being constructed as a validation platform for advanced sensor and control development. The demonstration platform is a suitable application in advanced reactor designs that present challenging environments and operational demands. Consequently, the benefits from enhanced control system capabilities can be clearly assessed while the project outcome will also fulfill a need for improved technology to meet the goals of advanced reactor performance. Additionally, the complexity of the system is such that traditional control techniques are inadequate and more advanced techniques need to be utilized for the system to be feasible. The cost of nuclear energy is directly related to the cost and reliability of nuclear power plant (NPP) components. Deeply embedding instrumentation and controls (I&C) within these components has the potential to significantly increase the reliability of the components while enabling otherwise unobtainable performance and reduced maintenance cost. Directly measuring changes in component characteristics and performance can obviate a significant portion of component maintenance, which is both time-consuming and expensive in itself and, more importantly, lowers plant availability. Embedding I&C within components is key to observing degradation in the component and predicting remaining useful life.

关键词：传感器；控制系统；核反应堆安全；堆内构件

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Colourimetric sensors and indicators are widely used because of their low cost and simplicity. A significant challenge associated with the design of this type of device is that the sensing mechanism must be simultaneously optimised for the sensitivity of the response and a visually perceptible colour change. Structural colour, derived from coherent scattering rather than molecular absorption, is a promising route to colourimetric sensor design because colour shifts are tied to changes in one of many physical properties of a material, rather than a specific chemical process. This Feature Article presents an overview of the development of low-cost sensors and indicators that exploit structural colour. Building upon recent advances in structurally adaptive materials design, structural colour sensors have been developed for a wide variety of previously inaccessible physical (e.g. temperature, strain, electric fields) and chemical stimuli (e.g. small organic molecules, charged species, biomacromolecules and metabolites). These devices, often exceeding the state of the art in performance, simplicity or both, have bright prospects for market impact in areas such as environmental monitoring, workplace hazard identification, threat detection, and point-of-care diagnostics. Finding the ideal balance between performance (e.g. sensitivity, specificity, reproducibility, etc.) and simplicity (e.g. colourimetric vs. spectroscopic readout) will be one of the most critical elements in the further development of structural colour sensors. This balance should be driven largely by the market demands and competing technologies.

关键词：传感器；比色分析法；比色法；检测器

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Assessing snow cover patterns in mountain regions remains a challenge for a variety of reasons. Topography (e.g., elevation, exposure, aspect, and slope) strongly influences snowfall accumulation and subsequent ablation processes, leading to pronounced spatial variability of snow cover. In-situ observations are typically limited to open areas at lower elevations (<1000 m). In this paper, we use several products from the Moderate Resolution Imaging Spectroradiometer (MODIS) to assess snow cover extent in the Southern Appalachian Mountains (SAM). MODIS daily snow cover maps and true color imagery are analyzed after selected snow events (e.g., Gulf/Atlantic Lows, Alberta Clippers, and Northwest Upslope Flow) from 2006 to 2012 to assess the spatial patterns of snowfall across the SAM. For each event, we calculate snow cover area across the SAM using MODIS data and compare with the Interactive Multi-sensor Snow and ice mapping system (IMS) and available in-situ observations. Results indicate that Gulf/Atlantic Lows are typically responsible for greater snow extent across the entire SAM region due to intensified cyclogenesis associated with these events. Northwest Upslope Flow events result in snow cover extent that is limited to higher elevations (1000 m) across the SAM, but also more pronounced along NW aspects. Despite some limitations related to the presence of ephemeral snow or cloud cover immediately after each event, we conclude that MODIS products are useful for assessing the spatial variability of snow cover in heavily forested mountain regions such as the SAM.

关键词：传感器；辐射度；冰映射；多传感器

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The results of supersonic wind-tunnel tests on three probes at nominal Mach numbers of 1.6, 1.8 and 2.0 and flight tests on two of these probes up to a Mach number of 1.9 are described. One probe is an 8 deg. half-angle wedge with two total-pressure measurements and one static. The second, a conical probe, is a cylinder that has a 15 deg., semi-angle cone tip with one total-pressure orifice at the apex and four static-pressure orifices on the surface of the cone, 90 deg. apart, and about two-thirds of the distance from the cone apex to the base of the cone. The third is a 2 deg. semi-angle cone that has two static ports located 180 deg. apart about 1.5 inches behind the apex of the cone. The latter probe was included since it has been the "probe of choice" for wind-tunnel flow-field pressure measurements (or one similar to it) for the past half-century. The wedge and 15 deg. conical probes used in these tests were designed for flight diagnostic measurements for flight Mach numbers down to 1.35 and 1.15 respectively, and have improved capabilities over earlier probes of similar shape. The 15. conical probe also has a temperature sensor that is located inside the cylindrical part of the probe that is exposed to free-stream flow through an annulus at the apex of the cone. It enables the determination of free-stream temperature, density, speed of sound, and velocity, in addition to free-stream pressure, Mach number, angle of attack and angle of sideslip. With the time-varying velocity, acceleration can be calculated. Wind-tunnel tests of the two probes were made in NASA Langley Research Center fs Unitary Plan Wind Tunnel (UPWT) at Mach numbers of 1.6, 1.8, and 2.0. Flight tests were carried out at the NASA Dryden Flight Research Center (DFRC) on its F-15B aircraft up to Mach numbers of 1.9. The probes were attached to a fixture, referred to as the Centerline Instrumented Pylon (CLIP), under the fuselage of the aircraft. Problems controlling the velocity of the flow through the conical probe required for accurate temperature measurements are noted, as well as some calibration problems of the miniature pressure sensors that required a re-calculation of the flow variables. Data are presented for angle of attack, pressure and Mach number obtained in the wind tunnel and in flight. In the wind tunnel some transient data were obtained by translating the probes through the shock flow field created by a bump on the wind-tunnel wall.

关键词：传感器；超音速流动；风洞试验；流量分布

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For this study, a novel optical fiber sensing system was developed and tested for the monitoring of corrosion in transportation systems. The optical fiber sensing system consists of a reference long period fiber gratings (LPFG) sensor for corrosive environmental monitoring and a LPFG sensor coated with a thin film of nano iron and silica particles for steel corrosion monitoring. The environmental effects (such as pH and temperature) are compensated by the use of the reference LPFG sensor. The sensor design, simulation, and experimental validation were performed in this study to investigate the feasibility of the proposed sensing system for corrosion and environment monitoring. The detailed investigations of the proposed sensing system showed that within the detection limitation of the thin coated layer, the proposed sensor could monitor both the initial and stable corrosion rate consistently. Compared to the traditional electrochemical method, the proposed optical fiber sensing system has a converter coefficient of 1 nm/day=3.746(10-3 A/cm2). Therefore, the proposed nano iron/silica particles dispersed polyurethane coated optical fiber sensor can monitor the critical corrosion information of the host members in real time and remotely. With multiple LPFGs in a single fiber, it is possible to provide a cost-effective, distributed monitoring solution for corrosion monitoring of large scale transportation structures.

关键词：传感器；光纤；防腐；交通系统

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