After the recent success in jamming wireless improvised explosive devices (IEDs), the threat nowadays has shifted towards the use of buried command wires. A capability to immediately detect the presence of a command wire would be of great value to the troops on the ground. The major challenge of a command wire sensor is to detect the wire in clutter and achieve a high probability of detection without large number of false alarms. The objective of this thesis is to investigate the wire scattering behavior and clutter characteristics through measurements performed in the NPS anechoic chamber. The research has successfully resolved the various multipath components within the anechoic chamber. The transmit-receive coupling between the antennas was reduced through the appropriate use of absorbers. Various wire scattering and clutter characteristics were established through the measurement results. In addition, the measurement results have also demonstrated close-in clutter rejection by utilizing time gating. Recommendations for future work were proposed to gather more data to support the ongoing NPS research on the Command Wire Sensor design.

关键词：光机电；传感器；控制导线；测量

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The objective of the project is to undertake research and development in the area of wireless sensor networks to provide an effective and affordable solution in support increasing requirements for reconnaissance and surveillance. A wireless sensor network, such as unattended ground sensors (UGS) network represents a set of inexpensive sensors of various types (modes) that provide an effective and affordable solution for battlefield surveillance. For example, acoustic sensors could obtain bearing angles of targets, and proximity sensors report the presence or absence of targets within their sensing ranges. The ultimate goal of this research is to explore fundamental performance bounds that determine how well a sensor network can resolve and localize multiple targets as a function of the operating parameters such as sensor density, the threshold settings, and the spacing between the targets. The major contribution of this project is the development of the particle-based probability density (PHD) filter for binary measurements using proximity sensors.

关键词：光机电；传感器；融合；追踪

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This study demonstrated the use of a unique prototype gas chromatograph with sensor array detection, the analytical components of which are microfabricated from Si (micro-GC), for analysis of indoor air concentrations of trichloroethylene (TCE) at low- and sub ppb levels, related to vapor intrusion (VI) applications. The objectives of this study were to demonstrate the performance of the prototype micro-GC in two operating modes: portable mode for forensic and spatial monitoring; and fixed location mode for longer term temporal monitoring (exposure estimation). Results from the micro GC and from TO -15 reference samples were compared. Above the mitigation action level (MAL; 2.3 ppb), the micro-GC accurately determined TCE under complex field matrix conditions. Below the MAL, TCE micro GC determinations were positively biased due to unresolved interferences. This study stands as the first of its kind, where micro-GC instrumentation was shown capable of sustained, reliable, automated measurements of a trace-level component (TCE) in a complex VOC mixture in real-world environments.

关键词：光机电；传感器；土壤蒸气入侵；应用

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Traumatic brain injuries (TBIs) result from exposure to high accelerations and are a serious threat to Soldiers in close contact with improvised explosive devices as well as sports players who are frequently involved in collisions. To improve TBI detection, the U.S. Army Research Laboratory (ARL) has developed a sensor small enough to be mounted in the ear. The sensor consists of an array of 3-axis microelectromechanical system (MEMS) acceleration threshold switches with different sensitivities that move to contacts under acceleration and complete a circuit. Previously, the outputs, which were voltage levels, required an analog-to-digital converter, but the implementation of the mechanism introduced a delay of 100 microsecs samples. This delay has caused the loss of data from switch closures that last less than 100 microsecs, so the sensor was redesigned with digital outputs, and a new program was developed. Clocked signals were used to simulate sensor data, and tests showed improved delays of 3 microsecs to 10 microsecs.

关键词：光机电；传感器；单片机；微机电系统

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Pedemis (PortablE Decoupled Electromagnetic Induction Sensor) is a time-domain handheld electromagnetic induction (EMI) instrument with the intended purpose of improving the detection and classification of UneXploded Ordnance (UXO). Pedemis sports nine coplanar transmitters (the Tx assembly) and nine triaxial receivers held in a fixed geometry with respect to each other (the Rx assembly) but with that Rx assembly physically decoupled from the Tx assembly allowing flexible data acquisition modes and deployment options. The data acquisition (DAQ) electronics consists of the National Instruments (NI) cRIO platform which is much lighter and more energy efficient that prior DAQ platforms. Pedemis has successfully acquired initial data, and inversion of the data acquired during these initial tests has yielded satisfactory polarizabilities of a spherical target. In addition, precise positioning of the Rx assembly has been achieved via position inversion algorithms based solely on the data acquired from the receivers during the on-time of the primary field. Pedemis has been designed to be a flexible yet user friendly EMI instrument that can survey, detect and classify targets in a one pass solution. In this paper, the Pedemis instrument is introduced along with its operation protocols, initial data results, and current status.

关键词：光机电；传感器；电磁感应；集成定位

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In Section 2.2.5.4 it was indicated that, in general, for nonlinear parametriza-tion of the system responses, optimum experimental conditions strongly depend on the unknown parameter values which only have to be estimated. This causes one of the main complications related to the determination of optimal experimental conditions. A common approach is then to design the experiment for some reasonable nominal parameter values whose knowledge is a prerequisite for applying the locally optimal sensor location methods described in the previous chapters. Since the uncertainty of those nominal values is not taken into account, practical application of such procedures is limited to situations when system responses change slowly in the set of admissible parameters.

关键词：光机电；传感器；位置参数；不确定性

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This document is a final report for the polyvinyl toluene (PVT) neutron-gamma (PVT-NG) project, which was sponsored by the Domestic Nuclear Detection Office (DNDO). The PVT-NG sensor uses PVT detectors for both gamma and neutron detection. The sensor exhibits excellent spectral resolution and gain stabilization, which are features that are beneficial for detection of both gamma-ray and neutron sources. In fact, the ability to perform isotope identification based on spectra that were measured by the PVT-NG sensor was demonstrated. As described in a previous report, the neutron sensitivity of the first version of the prototype was about 25less than the DNDO requirement of 2.5 cps/ng for bare Cf-252. This document describes design modifications that were expected to improve the neutron sensitivity by about 50relative to the PVT-NG prototype. However, the project was terminated before execution of the design modifications after portal vendors demonstrated other technologies that enable neutron detection without the use of He-3. Nevertheless, the PVT-NG sensor development demonstrated several performance goals that may be useful in future portal designs.

关键词：光机电；传感器；PVT-NG

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The complete list of nanostructured metal oxides and their response to different gaseous species and vapors is shown in Table A.24: The metal oxides include: aluminum, cadmium, cerium, cobalt, copper, gallium, indium, iridium, iron, molybdenum, niobium, nickel, tellurium, tin, titanium, tungsten, vanadium, zinc, zirconium, and mixed oxides. The gaseous species are: acetic acid, acetone, acetylene, ammonia, benzene, butane, carbon dioxide, carbon disulfide, carbon monoxide, chlorine, dimethyl methylphos-phonate, ethyl alcohol, ethylene, formaldehyde, helium, hexane, hydrogen, hydrogen sulfide, LPG, methane, methanol, methyl cyanide, nitrogen oxides, oxygen, ozone, petrol (gasoline), petroleum ether, propane, pro-pene, propanol, propylene, sulfur dioxide, sulfur hexafluoride, toluene, and xylene. Details of the nanostructures of various metal oxides are listed in Table A.2. As it is seen, the tin oxide nanostructures along with mixed oxides are dominating at present. Tungsten nanostructures very closely follow these two oxides. The intention of this table is to give a clear view of these nanostructures. Comparing Table A.2 with Table A.24, it is easy to draw and select the nanostructures for the desired application.

关键词：光机电；传感器；纳米结构；阵列

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In 2009/2010 NASA developed Technology Roadmaps.Technology Area 8 was Science Instruments, Observatories & Sensors Systems (SIOSS).SIOSS included:Technology Area Breakdown Structure (TABS);Key Technical Challenges;Roadmaps for Each Level 1 TABS.

关键词：光机电；传感器；天文台；NRC技术路线图

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In the first part of this chapter, some fundamental results of modern optimum experimental design theory were adopted to the framework of sensor networks with mobile nodes following the so-called 'direct approach' presented in the seminal paper [232]. The problem reduces to solving at each time instant a separate optimization task to which classical design algorithms can be applied. The drawbacks of this technique are the high demand for computational power due to the complexity of the resulting mathematical programming task, and the fact that only the measurability of the sensor trajectories can be guaranteed. It was shown that these difficulties can be reduced to some extent by suitable parametrization of the sensor paths. However, imposing additional control constraints (e.g., for collision avoidance or the sensor dynamics) complicates further the computational task and restricts the spectrum of potential applications.

关键词：光机电；传感器；路由；资源

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