Structural Health Monitoring has great potential to provide valuable information about the actual structural condition and can help optimize the management activities. However, few effective and robust monitoring methods exist which hinders a nationwide use of SHM in structural condition evaluations. The objective of this project was to research and develop methods for structural identification and damage detection based on strain monitoring using long-gauge fiber-optic sensors. In particular two universal parameters of beam-like structures were studied in detail: the neutral axis and deformed shape. Data from two structures were used for validation purposes: from on-site monitoring of the US202/NJ23 overpass and from lab testing of a scale-model of a similar structure. The conclusions are that while the neutral axis varies during dynamic events, it changes the location due to damage, and it can be located accurately using a probabilistic approach. Thus, it can be used as a damage sensitive feature. At least two sensors per cross-section are necessary for an accurate evaluation of the location of the neutral axis. The vertical displacement of beams can be calculated by double integration of the curvature. However, the double integration method affects the accuracy of the evaluation, and to achieve the most accurate result a linear combination of integration methods is recommended. At least three locations along each girder should be instrumented with two parallel sensors for accurate evaluation of the vertical displacement. The methodologies researched in this project are presented in this report and recommendations for the use of the methods provided.

关键词：传感器；桥梁（结构）；复合材料

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The major development of fingerprint technology in its shape, known as the wet-ink fingerprinting was initiated and improved for forensic applications by Scotland Yard about 100 years ago. However, the development of new fingerprinting methods has happened in recent years and continues to evolve. Fingerprint recognition technology is an integral part of criminal investigations. It is the basis for the design of numerous security systems in both private and public sector. It is also seen as an important tool for a variety of government organizations including Homeland Security, Immigration, Naturalization Services, and the Armed Forces, where fingerprinting procedures are used for recognition and verification of the identity for employees of federal departments and private contractors.

关键词：传感器；扫描仪；生物识别技术；指纹识别器

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The objective of this research is to evaluate the feasibility to employ quantitative acoustic emission (AE) techniques for monitoring of fatigue crack initiation and propagation in steel bridge members. Three A36 compact tension steel specimens were tested in the laboratory according the ASTM E647. AE sensor networks were deployed and recorded AE during the fatigue-type loading. Noise from the load application points represented a significant challenge. However, a number of events could be located and for a selected few a moment tensor inversion (MTI) was performed. Despite the challenges, the methodology has been completely established and evaluated, and can be used in future testing.

关键词：传感器；声探测；桥梁（结构）；裂纹扩展

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Why GAO Did This Study. Since 2002, MDA has spent approximately $98 billion and has requested $38 billion more through fiscal year 2018 to develop, test, and field a system to defend against enemy ballistic missiles. The BMDS is comprised of a command and control system, sensors that identify incoming threats, and intercepting missiles. GAO is mandated by law to assess the extent to which MDA has achieved its acquisition goals and objectives, as reported to Congress through its acquisition baselines, and to report on other issues as appropriate. This report examines the agency s progress and any challenges in fiscal year 2013 associated with (1) developing, flight testing, and producing individual systems, which MDA refers to as BMDS elements; and (2) reporting resource and schedule baselines that support oversight. To support this effort, GAO examined MDA s acquisition and test reports, analyzed two of MDA s acquisition baselines resource and schedule to discern progress, and interviewed a wide range of DOD and contractor officials. What GAO Recommends. GAO recommends (1) any changes to the SM-3 Block IB be flight tested before DOD approves full production; (2) retest the fielded GMD interceptor to demonstrate performance; and (3) improve the content of its schedule baselines. DOD partially concurred with the first, non-concurred with the second, and concurred with the third, stating that the production and testing decisions will be made using the proper DOD processes. GAO believes both recommendations are valid as discussed in this report.

关键词：传感器；弹道导弹防御系统；防御系统；探测器

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In preparation for a large rehabilitation project on the Anthony Wayne Bridge (AWB), the Ohio Department of Transportation has expressed interest in evaluating monitoring and protection strategies which may extend the life of the AWB. This study was proposed and performed in line with this goal. Corrosion of the main cable was identified as the driving mechanism for the aging of suspension bridges. Experiments were performed in order to determine whether or not the existing acoustic monitoring system on the AWB could be used to readily identify active corrosion. Results from laboratory testing show that use of acoustic emission to detect corrosion is possible and promising; however, field experiments indicate that additional tests are needed to determine the practicality of identifying corrosion in the field. The upcoming bridge closure will provide a great opportunity for researchers to more closely examine this possibility. In addition, this report includes literature investigation into other state-of-theart corrosion monitoring and protection strategies including an internal sensor array, the magnetic main flux method for wire inspection, and cable dehumidification.

关键词：传感器；动态结构分析；负荷试验；主电缆

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The objective of the Underwater Hull Analysis Model project was to develop a computational condition-based assessment tool to determine the condition of hull. The model would be an advancement in the state-of-the-art for corrosion and coatings damage assessment allowing for evaluation of hull condition based on sensor data in real or near real time. The computational tool was planned to be validated using both experimental and real ship data. An initial stage in the validation process is to determine the relationship between changes in defined boundary conditions and calculated field values. This information is a key component in the capability to identify changes in hull coating damage from changes in measured field values. The work presented is computational in nature. Damage on the order of what is possible to duplicate in physical scale model experiments is added to a known quality of damage. Variations in key calculated parameters are determined, and implications for the creation of the assessment tool are noted. This work provides information on the relationship between incremental damage change and measurable field differences.

关键词：传感器；腐蚀；损害评估；电场

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This report describes work in Phase I of the OUTBIDS project under the DARPA MSEE program. The goal of OUTBIDS was to develop the theoretical and technological foundations for sensor data interpretation as a form of probabilistic inference. Achieving this goal requires a representation formalism for probability models of sufficient expressive power to handle the complexity of real-world sensor data. The problem involves two primary sources of difficulty: first, the underlying world generating the data typically contains many initially unknown objects interacting over time in complex ways; second, the mapping from objects and behaviors to sensor data is itself (as in the case of visual perception, for example) very complex. The core of the project is the BLOG (Bayesian LOGic) language, which combines probabilistic semantics with the expressive power of first-order logic. Unlike other attempts to combine probability and logic, BLOG supports open-universe models, which allow for uncertainty over the existence and identity of objects. We believe this is a prerequisite for any probabilistic approach to general perception. The team made substantial progress on developing and refining the BLOG language by writing a broad range of models, including two models for computer vision tasks (adaptive video background subtraction for object tracking and a simple form of 3D object recognition and scene reconstruction). We also made good progress towards an efficient inference engine, including new algorithms and initial work on compiler and parallelization technology for BLOG inference. We showed that BLOG could be extended to open-universe decision models and developed algorithms for sensor planning on this basis. We also developed a new theoretical framework for utility-directed inference and proved several foundational theorems.

关键词：传感器；贝叶斯定理；计算机程序

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Chloride ion ingress is an important parameter that helps estimate the durability and service life of reinforced concrete (RC) and prestress concrete (PC) structures, especially in those structures exposed to marine environments and salts applied during the winter season for traffic safety. Current techniques used to detect chloride content and monitor the level of corrosion in RC and PC structures, such as acoustic emission (AE), fiber optics, and electrochemical measurements, are time consuming, and invasive. In addition, they require external power sources, complex test setups, are expensive to implement, and often, it is difficult to interpret the data recorded in the field. In an effort to overcome these restrictions, an inexpensive, wireless corrosion detector sensor based on commercial radio frequency identification (RFID) technology that does not need to be powered by a local source of energy, has been developed by an Oklahoma State Universitys research team. The purpose of the first phase of this project was to implement this innovative RFID corrosion sensor into a new bridge construction to collect data during monitoring to study both the reliability and field performance of the sensor in-situ and under laboratory conditions. The laboratory work attempted to correlate the sensors sensitivity to the level of corrosion in the structure. Phase II of this work will be focused on the long-term monitoring of the sensors installed in the field for a period of approximately 10 years.

关键词：传感器；外加剂；氯化物；混凝土路面；腐蚀抑制剂

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This report focuses on the temperature increase that occurred within the RA throughout the 4-day-long tests. In the following discussion of the test setup, a complete description of the actual test setup is given. While this description provides details on all of the sensors used during OMSHRs testing, the data measured using some of the sensors will not be discussed within this report. The intent is to write a second document in the future that will discuss heat transfer from the RA to the mine. The outputs of these sensors will be used in this future publication.

关键词：传感器；传热；矿井灾害；矿山逃生；井下救援

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The Defense Threat Reduction Agency and the Air Force Office of Scientific Research require sensors to detect biological agents better, faster, and cheaper. This research explores the use of graphene functionalized with single strand deoxyribonucleic acid (ssDNA) aptamers as a detection method for the Sterne strain of Bacillus anthracis. This research is interesting because of the unique electrical and chemical binding properties of graphene and its interaction with ssDNA and DNA. The interactions of graphene functionalized with ssDNA in response to B. anthracis spores, non-complimentary and complimentary DNA were explored in static and dynamic aqueous environments with indirect complimentary binding confirmation via Raman spectroscopy and atomic force microscopy. The results suggest aptamer functionalized graphene can be used to detect B. anthracis spores, non-complimentary and complimentary DNA sequences.

关键词：传感器；炭疽杆菌；生物剂探测器；生物战剂

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