In this study, modal control with various bases has been experimentally evaluated on an experimental Adaptive Optics (AO) testbed. In most custom-built adaptive optics control problems, spatial resolution and available stroke of the deformable mirror (DM) are assumed to be sufficient for the intended performance. In practice, however, there are situations where DMs of limited capability are used and the control system is desired to make most out of the hardware even in such situations. In this paper, the effect of the hardware limitations, such as the spatial resolution of the wavefront sensor and the deformable mirror (DM) on the performance of the AO system, is investigated and several control techniques are proposed to mitigate the problem. The derivatives of Zernike polynomials do not have the orthogonal property.A simple approximate orthogonalization technique is proposed along with the method to avoid the discrepancy of minimum error in the sensor output vector space and in the vector space where the control law is applied. An anti- windup technique is also proposed to reduce the adverse effect by an integral controller when saturation of the DM occurs. Effectiveness of the proposed techniques is demonstrated by experiments on the pseudo real-time AO testbed.

关键词：传感器；执行器；自适应滤波器；探测器；控制系统

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The subject research was performed at the University of Florida between December 2005 and December 2008. The research was performed to support the ability to detect landmines in an automated fashion using ground- penetrating radar (GPR) array sensors employed in systems being studied by NVESD. The work was concerned with discovering and evaluating i) different types of features that, when extracted from signals associated with GPR signals captured over regions of earth, can help one identify the presence or absence of landmines and landmine-like objects; (ii) algorithms and techniques that can employ these features to distinguish between landmines and non-mines; and (iii) fuse the results of multiple discriminators to yield improved discrimination performance.

关键词：传感器融合；探地雷达；地雷探测；探雷器；模式识别

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During the project, we have investigated the linear and nonlinear response of two dimensional gold square-nanopatch arrays. We have shown that these arrays exhibit very narrow resonances corresponding to the formation of leaky modes associated with surface plasmons at the air/metal interfaces. The experimental measurements have confirmed the spectral behaviour predicted by the simulations and emphasized that fabrication tolerances, such as the roughness, do not noticeably affect the performance of the device since they broaden and shift slightly the plasmonic resonances. Then the potential sensitivity of the device has been experimentally derived by evaluating the spectral shift when an extremely small change of the refractive index is induced at the top surface of the sensor, leading to sensitivity values up to 1000 nm/RIU and a corresponding Figure of Merit (FOM) of 222 RIU-1 (FWHM of the resonance is only 4.5 nm). Moreover, we have shown a new, more intuitive path to detect variations of refractive index from colour changes. We compared the diffracted spectra of the same sample with air and an IPA solution on top, registering a significant change in the sample colour. This observation can be also quantified in terms of sensitivity, leading to S = 121 nm/RIU and FOM = 6 RIU-1 (FWHM of the measured spectra is equal to 20 nm). Furthermore, such observation method allows establishing numerous other properties of the foreign compound such as its thickness or evaporation time, paving the way for new, yet unexplored plasmonic sensor devices. Finally the nonlinear response of the periodic arrays has been investigated and the effect of the geometrical parameters on the Surface Enhanced Raman Scattering signal has been analyzed.

关键词：传感器；纳米结构阵列；探测器；拉曼散射；仿真

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Lean combustion concepts for aircraft engine combustors are prone to combustion instabilities. Mitigation of instabilities is an enabling technology for these low-emissions combustors. NASA Glenn Research Center s prior activity has demonstrated active control to suppress a high-frequency combustion instability in a combustor rig designed to emulate an actual aircraft engine instability experience with a conventional, rich-front-end combustor. The current effort is developing further understanding of the problem specifically as applied to future lean-burning, very low-emissions combustors. A prototype advanced, low-emissions aircraft engine combustor with a combustion instability has been identified and previous work has characterized the dynamic behavior of that combustor prototype. The combustor exhibits thermoacoustic instabilities that are related to increasing fuel flow and that potentially prevent full-power operation. A simplified, non-linear oscillator model and a more physics-based sectored 1-D dynamic model have been developed to capture the combustor prototype s instability behavior. Utilizing these models, the NASA Adaptive Sliding Phasor Average Control (ASPAC) instability control method has been updated for the low-emissions combustor prototype. Active combustion instability suppression using the ASPAC control method has been demonstrated experimentally with this combustor prototype in a NASA combustion test cell operating at engine pressures, temperatures, and flows. A high-frequency fuel valve was utilized to perturb the combustor fuel flow. Successful instability suppression was shown using a dynamic pressure sensor in the combustor for controller feedback. Instability control was also shown with a pressure feedback sensor in the lower temperature region upstream of the combustor. It was also demonstrated that the controller can prevent the instability from occurring while combustor operation was transitioning from a stable, low-power condition to a normally unstable high-power condition, thus enabling the high-power condition.

关键词：压力传感器；振荡器；燃气涡轮发动机；动态模型

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Military conflicts are shifting from jungles and deserts to cities. This is because terrorists, insurgents, and guerrillas find that these areas provide a rich target environment and good hideouts. With the use of UAVs, urban threats can be effectively tracked and targeted. However, in urban environments where there is little or no GPS signal and many obstacles, navigation of UAVs is a major challenge. Multiple UAVs can be employed to share sensor information to counter these challenges and to perform Intelligence, Surveillance, and Reconnaissance (ISR) missions with greater ground coverage and better success rates. This thesis explores the various types of UAVs deployed for urban operations, and investigates trends in the design of such UAVs in terms of their weight, altitude, speed, and sensor suite. The thesis discusses the challenges and requirements for interoperability of multi-UAVs in urban environments, and proposes a direct-method-based control system for multiple UAV collaboration and obstacle collision avoidance. A dynamic model was developed for the simulation testing of the control system algorithm, which was followed by a physical experiment in an indoor environment using Quanser QBall-X4 UAVs to evaluate the results. Results show that the UAVs were able to share and integrate their sensors' information for joint cooperation.

关键词：传感器；自主导航；控制系统；计算机仿真

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trapping K_4[Fe(CN)_6] solution to detect the existence and quantitative concentration of proteins, where, as the minimum value, 4 molecules of protein are calculated to be detected per one molecule of DPPC liposome. Also, investigated several basic properties in the leakage current sensor. Especially, the addition of guanidinium hydrochloride (GuHCl) as protein denaturant successfully resulted in a prominent improvement in sensitivity.

关键词：生物传感器；化学和生物传感器；脂质体；电解液

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With the tragic passing this year of Gregory Leptoukh, the Earth and Space Sciences community lost a tireless participant in--and advocate for--science informatics. Throughout his career at NASA, Dr. Leptoukh established a theme of bridging the gulf between the informatics and science communities. Nowhere is this more evident than his leadership in the development of Giovanni (GES DISC Interactive Online Visualization ANd aNalysis Infrastructure). Giovanni is an online tool that serves to hide the often-complex technical details of data format and structure, making science data easier to explore and use by Earth scientists. To date Giovanni has been acknowledged as a contributor in 500-odd scientific articles. In recent years, Leptoukh concentrated his efforts on multi-sensor data inter-comparison, merging and fusion. This work exposed several challenges at the intersection of data and science. One of these was the ease with which a naive user might generate spurious comparisons, a potential hazard that was the genesis of the Multi-sensor Data Synergy Advisor (MDSA). The MDSA uses semantic ontologies and inference rules to organize knowledge about dataset quality and other salient characteristics in order to advise users on potential caveats for comparing or merging two datasets. Recently, Leptoukh also led the development of AeroStat, an online Giovanni instance to investigate aerosols via statistics from station and satellite comparisons and merged maps of data from more than one instrument. Aerostat offers a neural net based bias adjustment to harmonize the data by removing systematic offsets between datasets before merging. These examples exhibit Leptoukh's talent for adopting advanced computer technologies in the service of making science data more accessible to researchers. In this, he set an example that is at once both vital and challenging for the ESSI community to emulate.

关键词：传感器；计算机系统设计；地球科学；多传感器应用程序；数据系统

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Cantilever-based sensors present a platform for monitoring chemical reactions and detecting chemical compounds based on nanomechanical effects. Cantilever sensors have become popular because they offer rapid, label-free sensing possibility in a miniaturized platform, readily opening up applications for hand-held and portable devices [1-3]. The sensing ability of the cantilevers is intrinsic since the range of molecules/chemicals that can be detected is not determined by the sensor itself but on the available receptor coatings. The cantilever sensor is simply a transducer of the chemical reactions occurring on its surface.

关键词：传感器；悬臂式；纳米机械效应；化学反应

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A campus grid, a computational grid confined to a campus, requires temperature monitoring by huge number of sensors if it is to run without air-conditioning. To reduce the number of temperature sensors for the monitoring, a sensor location optimization method based on analysis of thermal behavior is proposed. The method eliminates sensors based on correlation between source heat and inlet temperature of PCs, The method enables to eliminate the sensors that are not sensitive to heat source, and results in sensor location optimization. Initial experiments in an actual campus grid show that such sensitivity does exist and clarify advantages of the method against simple optimization method based on just temperature.

关键词：传感器；位置优化；历史分析；相关分析

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Due to the United States' dependency on maritime travel, the proliferation of efficient and inexpensive naval mines poses a tremendous risk. Current mine countermeasure (MCM) technologies have a narrow field of view, preventing timely, wide-area searches. These technologies require the operator to be in proximity to the targets, a dangerous scenario made worse when in denied territory. In an effort to mitigate these risks, the use of an airborne hyperspectral sensor is proposed. The operational ability of a hyperspectral sensor to detect sub-pixel surface and submerged mines in non-littoral environments was evaluated using two common anomaly detectors: Mixture Tuned Matched Filtering (MTMF) and Reed-Xiaoli (RX). Due to the unavailability of the DoD's Spectral Infrared Imaging Technology Testbed (SPIRITT), ProSpecTIR-VS3, a sensor similar spatially and spectrally to SPIRITT was flown over a Navy test range offshore California. This experiment included three surface and three submerged targets, each with a 0.8 meter diameter. The spatial resolution of the images is dependent on the altitude of the sensor. In an effort to collect both a high spatial resolution and a low spatial resolution data set, two flight altitudes were planned. The high spatial resolution collection altitude was approximately 410 meters and the low spatial resolution altitude was approximately 800 meters. The spatial resolutions of the collections were 0.5 and 1.0 meters, respectively. This allowed for both a resolved and an unresolved analysis. While both anomaly detection techniques were found to have their flaws, the success of the study is in proving the usefulness of hyperspectral data for sub-pixel mine detection.

关键词：传感器；远程探测器；光谱异常检测；匹配过滤器

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