Science.gov

Sample records for adaptive sensor fleet

  1. Tele-Supervised Adaptive Ocean Sensor Fleet

    NASA Technical Reports Server (NTRS)

    Lefes, Alberto; Podnar, Gregg W.; Dolan, John M.; Hosler, Jeffrey C.; Ames, Troy J.

    2009-01-01

    The Tele-supervised Adaptive Ocean Sensor Fleet (TAOSF) is a multi-robot science exploration architecture and system that uses a group of robotic boats (the Ocean-Atmosphere Sensor Integration System, or OASIS) to enable in-situ study of ocean surface and subsurface characteristics and the dynamics of such ocean phenomena as coastal pollutants, oil spills, hurricanes, or harmful algal blooms (HABs). The OASIS boats are extended- deployment, autonomous ocean surface vehicles. The TAOSF architecture provides an integrated approach to multi-vehicle coordination and sliding human-vehicle autonomy. One feature of TAOSF is the adaptive re-planning of the activities of the OASIS vessels based on sensor input ( smart sensing) and sensorial coordination among multiple assets. The architecture also incorporates Web-based communications that permit control of the assets over long distances and the sharing of data with remote experts. Autonomous hazard and assistance detection allows the automatic identification of hazards that require human intervention to ensure the safety and integrity of the robotic vehicles, or of science data that require human interpretation and response. Also, the architecture is designed for science analysis of acquired data in order to perform an initial onboard assessment of the presence of specific science signatures of immediate interest. TAOSF integrates and extends five subsystems developed by the participating institutions: Emergent Space Tech - nol ogies, Wallops Flight Facility, NASA s Goddard Space Flight Center (GSFC), Carnegie Mellon University, and Jet Propulsion Laboratory (JPL). The OASIS Autonomous Surface Vehicle (ASV) system, which includes the vessels as well as the land-based control and communications infrastructure developed for them, controls the hardware of each platform (sensors, actuators, etc.), and also provides a low-level waypoint navigation capability. The Multi-Platform Simulation Environment from GSFC is a surrogate

  2. The telesupervised adaptive ocean sensor fleet

    NASA Astrophysics Data System (ADS)

    Elfes, Alberto; Podnar, Gregg W.; Dolan, John M.; Stancliff, Stephen; Lin, Ellie; Hosler, Jeffrey C.; Ames, Troy J.; Moisan, John; Moisan, Tiffany A.; Higinbotham, John; Kulczycki, Eric A.

    2007-09-01

    We are developing a multi-robot science exploration architecture and system called the Telesupervised Adaptive Ocean Sensor Fleet (TAOSF). TAOSF uses a group of robotic boats (the OASIS platforms) to enable in-situ study of ocean surface and sub-surface phenomena. The OASIS boats are extended-deployment autonomous ocean surface vehicles, whose development is funded separately by the National Oceanic and Atmospheric Administration (NOAA). The TAOSF architecture provides an integrated approach to multi-vehicle coordination and sliding human-vehicle autonomy. It allows multiple mobile sensing assets to function in a cooperative fashion, and the operating mode of the vessels to range from autonomous control to teleoperated control. In this manner, TAOSF increases data-gathering effectiveness and science return while reducing demands on scientists for tasking, control, and monitoring. It combines and extends prior related work done by the authors and their institutions. The TAOSF architecture is applicable to other areas where multiple sensing assets are needed, including ecological forecasting, water management, carbon management, disaster management, coastal management, homeland security, and planetary exploration. The first field application chosen for TAOSF is the characterization of Harmful Algal Blooms (HABs). Several components of the TAOSF system have been tested, including the OASIS boats, the communications and control interfaces between the various hardware and software subsystems, and an airborne sensor validation system. Field tests in support of future HAB characterization were performed under controlled conditions, using rhodamine dye as a HAB simulant that was dispersed in a pond. In this paper, we describe the overall TAOSF architecture and its components, discuss the initial tests conducted and outline the next steps.

  3. Path Planning Algorithms for the Adaptive Sensor Fleet

    NASA Technical Reports Server (NTRS)

    Stoneking, Eric; Hosler, Jeff

    2005-01-01

    The Adaptive Sensor Fleet (ASF) is a general purpose fleet management and planning system being developed by NASA in coordination with NOAA. The current mission of ASF is to provide the capability for autonomous cooperative survey and sampling of dynamic oceanographic phenomena such as current systems and algae blooms. Each ASF vessel is a software model that represents a real world platform that carries a variety of sensors. The OASIS platform will provide the first physical vessel, outfitted with the systems and payloads necessary to execute the oceanographic observations described in this paper. The ASF architecture is being designed for extensibility to accommodate heterogenous fleet elements, and is not limited to using the OASIS platform to acquire data. This paper describes the path planning algorithms developed for the acquisition phase of a typical ASF task. Given a polygonal target region to be surveyed, the region is subdivided according to the number of vessels in the fleet. The subdivision algorithm seeks a solution in which all subregions have equal area and minimum mean radius. Once the subregions are defined, a dynamic programming method is used to find a minimum-time path for each vessel from its initial position to its assigned region. This path plan includes the effects of water currents as well as avoidance of known obstacles. A fleet-level planning algorithm then shuffles the individual vessel assignments to find the overall solution which puts all vessels in their assigned regions in the minimum time. This shuffle algorithm may be described as a process of elimination on the sorted list of permutations of a cost matrix. All these path planning algorithms are facilitated by discretizing the region of interest onto a hexagonal tiling.

  4. Cooperative aquatic sensing using the telesupervised adaptive ocean sensor fleet

    NASA Astrophysics Data System (ADS)

    Dolan, John M.; Podnar, Gregg W.; Stancliff, Stephen; Low, Kian Hsiang; Elfes, Alberto; Higinbotham, John; Hosler, Jeffrey; Moisan, Tiffany; Moisan, John

    2009-09-01

    Earth science research must bridge the gap between the atmosphere and the ocean to foster understanding of Earth's climate and ecology. Typical ocean sensing is done with satellites or in situ buoys and research ships which are slow to reposition. Cloud cover inhibits study of localized transient phenomena such as Harmful Algal Blooms (HAB). A fleet of extended-deployment surface autonomous vehicles will enable in situ study of characteristics of HAB, coastal pollutants, and related phenomena. We have developed a multiplatform telesupervision architecture that supports adaptive reconfiguration based on environmental sensor inputs. Our system allows the autonomous repositioning of smart sensors for HAB study by networking a fleet of NOAA OASIS (Ocean Atmosphere Sensor Integration System) surface autonomous vehicles. In situ measurements intelligently modify the search for areas of high concentration. Inference Grid and complementary information-theoretic techniques support sensor fusion and analysis. Telesupervision supports sliding autonomy from high-level mission tasking, through vehicle and data monitoring, to teleoperation when direct human interaction is appropriate. This paper reports on experimental results from multi-platform tests conducted in the Chesapeake Bay and in Pittsburgh, Pennsylvania waters using OASIS platforms, autonomous kayaks, and multiple simulated platforms to conduct cooperative sensing of chlorophyll-a and water quality.

  5. The Telesupervised Adaptive Ocean Sensor Fleet (TAOSF) Architecture: Coordination of Multiple Oceanic Robot Boats

    NASA Technical Reports Server (NTRS)

    Elfes, Alberto; Podnar, Gregg W.; Dolan, John M.; Stancliff, Stephen; Lin, Ellie; Hosler, Jeffrey C.; Ames, Troy J.; Higinbotham, John; Moisan, John R.; Moisan, Tiffany A.; Kulczycki, Eric A.

    2008-01-01

    Earth science research must bridge the gap between the atmosphere and the ocean to foster understanding of Earth s climate and ecology. Ocean sensing is typically done with satellites, buoys, and crewed research ships. The limitations of these systems include the fact that satellites are often blocked by cloud cover, and buoys and ships have spatial coverage limitations. This paper describes a multi-robot science exploration software architecture and system called the Telesupervised Adaptive Ocean Sensor Fleet (TAOSF). TAOSF supervises and coordinates a group of robotic boats, the OASIS platforms, to enable in-situ study of phenomena in the ocean/atmosphere interface, as well as on the ocean surface and sub-surface. The OASIS platforms are extended deployment autonomous ocean surface vehicles, whose development is funded separately by the National Oceanic and Atmospheric Administration (NOAA). TAOSF allows a human operator to effectively supervise and coordinate multiple robotic assets using a sliding autonomy control architecture, where the operating mode of the vessels ranges from autonomous control to teleoperated human control. TAOSF increases data-gathering effectiveness and science return while reducing demands on scientists for robotic asset tasking, control, and monitoring. The first field application chosen for TAOSF is the characterization of Harmful Algal Blooms (HABs). We discuss the overall TAOSF architecture, describe field tests conducted under controlled conditions using rhodamine dye as a HAB simulant, present initial results from these tests, and outline the next steps in the development of TAOSF.

  6. Adaptive sensor fusion

    NASA Astrophysics Data System (ADS)

    Kadar, Ivan

    1995-07-01

    A perceptual reasoning system adaptively extracting, associating, and fusing information from multiple sources, at various levels of abstraction, is considered as the building block for the next generation of surveillance systems. A system architecture is presented which makes use of both centralized and distributed predetection fusion combined with intelligent monitor and control coupling both on-platform and off-board track and decision level fusion results. The goal of this system is to create a `gestalt fused sensor system' whose information product is greater than the sum of the information products from the individual sensors and has performance superior to either individual or a sub-group of combined sensors. The application of this architectural concept to the law enforcement arena (e.g. drug interdiction) utilizing multiple spatially and temporally diverse surveillance platforms and/or information sources, is used to illustrate the benefits of the adaptive perceptual reasoning system concept.

  7. Adaptive sensor fusion using genetic algorithms

    SciTech Connect

    Fitzgerald, D.S.; Adams, D.G.

    1994-08-01

    Past attempts at sensor fusion have used some form of Boolean logic to combine the sensor information. As an alteniative, an adaptive ``fuzzy`` sensor fusion technique is described in this paper. This technique exploits the robust capabilities of fuzzy logic in the decision process as well as the optimization features of the genetic algorithm. This paper presents a brief background on fuzzy logic and genetic algorithms and how they are used in an online implementation of adaptive sensor fusion.

  8. Distributed estimation for adaptive sensor selection in wireless sensor networks

    NASA Astrophysics Data System (ADS)

    Mahmoud, Magdi S.; Hassan Hamid, Matasm M.

    2014-05-01

    Wireless sensor networks (WSNs) are usually deployed for monitoring systems with the distributed detection and estimation of sensors. Sensor selection in WSNs is considered for target tracking. A distributed estimation scenario is considered based on the extended information filter. A cost function using the geometrical dilution of precision measure is derived for active sensor selection. A consensus-based estimation method is proposed in this paper for heterogeneous WSNs with two types of sensors. The convergence properties of the proposed estimators are analyzed under time-varying inputs. Accordingly, a new adaptive sensor selection (ASS) algorithm is presented in which the number of active sensors is adaptively determined based on the absolute local innovations vector. Simulation results show that the tracking accuracy of the ASS is comparable to that of the other algorithms.

  9. Specialized wavefront sensors for adaptive optics

    SciTech Connect

    Neal, D.R.; Mansell, J.D.; Gruetzner, J.K.

    1995-08-01

    The performance of an adaptive optical system is strongly dependent upon correctly measuring the wavefront of the arriving light. The most common wavefront measurement techniques used to date are the shearing interferometer and the Shack-Hartmann sensor. Shack-Hartmann sensors rely on the use of lenslet arrays to sample the aperture appropriately. These have traditionally been constructed using ULM or step and repeat technology, and more recently with binary optics technology. Diffractive optics fabrication methodology can be used to remove some of the limitations of the previous technologies and can allow for low-cost production of sophisticated elements. We have investigated several different specialized wavefront sensor configurations using both Shack-Hartmann and shearing interferometer principles. We have taken advantage of the arbitrary nature of these elements to match pupil shapes of detector and telescope aperture and to introduce magnification between the lenslet array and the detector. We have fabricated elements that facilitate matching the sampling to the current atmospheric conditions. The sensors were designed using a far-field diffraction model and a photolithography layout program. They were fabricated using photolithography and RIE etching. Several different designs will be presented with some experimental results from a small-scale adaptive optics brass-board.

  10. Adaptive sensor tasking using genetic algorithms

    NASA Astrophysics Data System (ADS)

    Shea, Peter J.; Kirk, Joe; Welchons, Dave

    2007-04-01

    Today's battlefield environment contains a large number of sensors, and sensor types, onboard multiple platforms. The set of sensor types includes SAR, EO/IR, GMTI, AMTI, HSI, MSI, and video, and for each sensor type there may be multiple sensing modalities to select from. In an attempt to maximize sensor performance, today's sensors employ either static tasking approaches or require an operator to manually change sensor tasking operations. In a highly dynamic environment this leads to a situation whereby the sensors become less effective as the sensing environments deviates from the assumed conditions. Through a Phase I SBIR effort we developed a system architecture and a common tasking approach for solving the sensor tasking problem for a multiple sensor mix. As part of our sensor tasking effort we developed a genetic algorithm based task scheduling approach and demonstrated the ability to automatically task and schedule sensors in an end-to-end closed loop simulation. Our approach allows for multiple sensors as well as system and sensor constraints. This provides a solid foundation for our future efforts including incorporation of other sensor types. This paper will describe our approach for scheduling using genetic algorithms to solve the sensor tasking problem in the presence of resource constraints and required task linkage. We will conclude with a discussion of results for a sample problem and of the path forward.

  11. Adaptive sensing based on profiles for sensor systems.

    PubMed

    Ishida, Yoshiteru; Tokumitsu, Masahiro

    2009-01-01

    This paper proposes a profile-based sensing framework for adaptive sensor systems based on models that relate possibly heterogeneous sensor data and profiles generated by the models to detect events. With these concepts, three phases for building the sensor systems are extracted from two examples: a combustion control sensor system for an automobile engine, and a sensor system for home security. The three phases are: modeling, profiling, and managing trade-offs. Designing and building a sensor system involves mapping the signals to a model to achieve a given mission. PMID:22291516

  12. Dynamic data-driven sensor network adaptation for border control

    NASA Astrophysics Data System (ADS)

    Bein, Doina; Madan, Bharat B.; Phoha, Shashi; Rajtmajer, Sarah; Rish, Anna

    2013-06-01

    Given a specific scenario for the border control problem, we propose a dynamic data-driven adaptation of the associated sensor network via embedded software agents which make sensor network control, adaptation and collaboration decisions based on the contextual information value of competing data provided by different multi-modal sensors. We further propose the use of influence diagrams to guide data-driven decision making in selecting the appropriate action or course of actions which maximize a given utility function by designing a sensor embedded software agent that uses an influence diagram to make decisions about whether to engage or not engage higher level sensors for accurately detecting human presence in the region. The overarching goal of the sensor system is to increase the probability of target detection and classification and reduce the rate of false alarms. The proposed decision support software agent is validated experimentally on a laboratory testbed for multiple border control scenarios.

  13. Chromatic adaptation performance of different RGB sensors

    NASA Astrophysics Data System (ADS)

    Susstrunk, Sabine E.; Holm, Jack M.; Finlayson, Graham D.

    2000-12-01

    Chromatic adaptation transforms are used in imaging system to map image appearance to colorimetry under different illumination sources. In this paper, the performance of different chromatic adaptation transforms (CAT) is compared with the performance of transforms based on RGB primaries that have been investigated in relation to standard color spaces for digital still camera characterization and image interchange. The chromatic adaptation transforms studied are von Kries, Bradford, Sharp, and CMCCAT2000. The RGB primaries investigated are ROMM, ITU-R BT.709, and 'prime wavelength' RGB. The chromatic adaptation model used is a von Kries model that linearly scales post-adaptation cone response with illuminant dependent coefficients. The transforms were evaluated using 16 sets of corresponding color dat. The actual and predicted tristimulus values were converted to CIELAB, and three different error prediction metrics, (Delta) ELab, (Delta) ECIE94, and (Delta) ECMC(1:1) were applied to the results. One-tail Student-t tests for matched pairs were calculated to compare if the variations in errors are statistically significant. For the given corresponding color data sets, the traditional chromatic adaptation transforms, Sharp CAT and CMCCAT2000, performed best. However, some transforms based on RGB primaries also exhibit good chromatic adaptation behavior, leading to the conclusion that white-point independent RGB spaces for image encoding can be defined. This conclusion holds only if the linear von Kries model is considered adequate to predict chromatic adaptation behavior.

  14. Adaptive multi-sensor integration for mine detection

    SciTech Connect

    Baker, J.E.

    1997-05-01

    State-of-the-art in multi-sensor integration (MSI) application involves extensive research and development time to understand and characterize the application domain; to determine and define the appropriate sensor suite; to analyze, characterize, and calibrate the individual sensor systems; to recognize and accommodate the various sensor interactions; and to develop and optimize robust merging code. Much of this process can benefit from adaptive learning, i.e., an output-based system can take raw sensor data and desired merged results as input and adaptively develop/determine an effective method if interpretation and merger. This approach significantly reduces the time required to apply MSI to a given application, while increasing the quality of the final result and provides a quantitative measure for comparing competing MSI techniques and sensor suites. The ability to automatically develop and optimize MSI techniques for new sensor suites and operating environments makes this approach well suited to the detection of mines and mine-like targets. Perhaps more than any other, this application domain is characterized by diverse, innovative, and dynamic sensor suites, whose nature and interactions are not yet well established. This paper presents such an outcome-based multi-image analysis system. An empirical evaluation of its performance and its application, sensor and domain robustness is presented.

  15. Adaptive wavefront sensor based on the Talbot effect

    NASA Astrophysics Data System (ADS)

    Podanchuk, Dmytro V.; Kurashov, Vitaliy N.; Kovalenko, Andrey V.; Dan'ko, Volodymyr P.; Kotov, Myhailo M.; Goloborodko, Nataliya S.

    2015-11-01

    The possibilities of wavefront curvature measuring by Talbot sensor are theoretically and experimentally investigated. A new method of wavefront aberrations measurement is proposed and demonstrated. It is based on the observation of the Talbot effect when the diffraction grating is adapted to the wavefront curvature of the analyzed wave. Herewith, the observation plane stay fixed and corresponds to the Talbot length for a plane wave. It is shown that the measurement range can be made several times wider, with the help of the adaptive Talbot sensor, by retaining the required angular sensitivity. A possibility of self-reproduction of the rectangular grating (with different periods along the axes) by the astigmatic wavefront is experimentally demonstrated. The possibility of the experimental realization of the adaptive Talbot sensor using the dynamic spatial light modulator is demonstrated.

  16. Adaptive and mobile ground sensor array.

    SciTech Connect

    Holzrichter, Michael Warren; O'Rourke, William T.; Zenner, Jennifer; Maish, Alexander B.

    2003-12-01

    The goal of this LDRD was to demonstrate the use of robotic vehicles for deploying and autonomously reconfiguring seismic and acoustic sensor arrays with high (centimeter) accuracy to obtain enhancement of our capability to locate and characterize remote targets. The capability to accurately place sensors and then retrieve and reconfigure them allows sensors to be placed in phased arrays in an initial monitoring configuration and then to be reconfigured in an array tuned to the specific frequencies and directions of the selected target. This report reviews the findings and accomplishments achieved during this three-year project. This project successfully demonstrated autonomous deployment and retrieval of a payload package with an accuracy of a few centimeters using differential global positioning system (GPS) signals. It developed an autonomous, multisensor, temporally aligned, radio-frequency communication and signal processing capability, and an array optimization algorithm, which was implemented on a digital signal processor (DSP). Additionally, the project converted the existing single-threaded, monolithic robotic vehicle control code into a multi-threaded, modular control architecture that enhances the reuse of control code in future projects.

  17. An Adaptive Sensor Mining Framework for Pervasive Computing Applications

    NASA Astrophysics Data System (ADS)

    Rashidi, Parisa; Cook, Diane J.

    Analyzing sensor data in pervasive computing applications brings unique challenges to the KDD community. The challenge is heightened when the underlying data source is dynamic and the patterns change. We introduce a new adaptive mining framework that detects patterns in sensor data, and more importantly, adapts to the changes in the underlying model. In our framework, the frequent and periodic patterns of data are first discovered by the Frequent and Periodic Pattern Miner (FPPM) algorithm; and then any changes in the discovered patterns over the lifetime of the system are discovered by the Pattern Adaptation Miner (PAM) algorithm, in order to adapt to the changing environment. This framework also captures vital context information present in pervasive computing applications, such as the startup triggers and temporal information. In this paper, we present a description of our mining framework and validate the approach using data collected in the CASAS smart home testbed.

  18. Wireless thermal sensor network with adaptive low power design.

    PubMed

    Lee, Ho-Yin; Chen, Shih-Lun; Chen, Chiung-An; Huang, Hong-Yi; Luo, Ching-Hsing

    2007-01-01

    There is an increasing need to develop flexible, reconfigurable, and intelligent low power wireless sensor network (WSN) system for healthcare applications. Technical advancements in micro-sensors, MEMS devices, low power electronics, and radio frequency circuits have enabled the design and development of such highly integrated system. In this paper, we present our proposed wireless thermal sensor network system, which is separated into control and data paths. Both of these paths have their own transmission frequencies. The control path sends the power and function commands from computer to each sensor elements by 2.4GHz RF circuits and the data path transmits measured data by 2.4GHz in sensor layer and 60GHz in higher layers. This hierarchy architecture would make reconfigurable mapping and pipeline applications on WSN possibly, and the average power consumption can be efficiently reduced about 60% by using the adaptive technique. PMID:18003354

  19. Emergent Adaptive Noise Reduction from Communal Cooperation of Sensor Grid

    NASA Technical Reports Server (NTRS)

    Jones, Kennie H.; Jones, Michael G.; Nark, Douglas M.; Lodding, Kenneth N.

    2010-01-01

    In the last decade, the realization of small, inexpensive, and powerful devices with sensors, computers, and wireless communication has promised the development of massive sized sensor networks with dense deployments over large areas capable of high fidelity situational assessments. However, most management models have been based on centralized control and research has concentrated on methods for passing data from sensor devices to the central controller. Most implementations have been small but, as it is not scalable, this methodology is insufficient for massive deployments. Here, a specific application of a large sensor network for adaptive noise reduction demonstrates a new paradigm where communities of sensor/computer devices assess local conditions and make local decisions from which emerges a global behaviour. This approach obviates many of the problems of centralized control as it is not prone to single point of failure and is more scalable, efficient, robust, and fault tolerant

  20. Biofied building: interactive and adaptive building using sensor agent robots

    NASA Astrophysics Data System (ADS)

    Mita, Akira

    2011-04-01

    Evaluating and recording building conditions in a quantitative manner such as level of deterioration and level of safety has been recognized an important research area and is called structural health monitoring (SHM). The (SHM) system has been studied and developed in our laboratory for many years. Our SHM system consists of a smart sensor network (for data acquisition), a database server, and a diagnosis and prognosis server. The SHM, however, can be extended to more novel roles - detecting and recording the histories of environmental conditions of building structures and flexibly adjust to the environments. Living matter has very flexible and smart adaption mechanisms in nature as categorized into four, sensory adaption, adaption by learning, physiological adaption, and evolutionary adaption. We would like to implement these adaption mechanisms into buildings. We call this concept "biofied building" or "biofication of living spaces" and are working to integrate the concept. We are particularly interested in using robots as sensor agents to gather information of buildings and residents and interact with them. The information obtained by the sensor agent robots is used to record all aspects of life phases of the environment relevant to buildings. This paper presents some aspects of the "biofied building" research conducted at our laboratory.

  1. Adaptive inferential sensors based on evolving fuzzy models.

    PubMed

    Angelov, Plamen; Kordon, Arthur

    2010-04-01

    A new technique to the design and use of inferential sensors in the process industry is proposed in this paper, which is based on the recently introduced concept of evolving fuzzy models (EFMs). They address the challenge that the modern process industry faces today, namely, to develop such adaptive and self-calibrating online inferential sensors that reduce the maintenance costs while keeping the high precision and interpretability/transparency. The proposed new methodology makes possible inferential sensors to recalibrate automatically, which reduces significantly the life-cycle efforts for their maintenance. This is achieved by the adaptive and flexible open-structure EFM used. The novelty of this paper lies in the following: (1) the overall concept of inferential sensors with evolving and self-developing structure from the data streams; (2) the new methodology for online automatic selection of input variables that are most relevant for the prediction; (3) the technique to detect automatically a shift in the data pattern using the age of the clusters (and fuzzy rules); (4) the online standardization technique used by the learning procedure of the evolving model; and (5) the application of this innovative approach to several real-life industrial processes from the chemical industry (evolving inferential sensors, namely, eSensors, were used for predicting the chemical properties of different products in The Dow Chemical Company, Freeport, TX). It should be noted, however, that the methodology and conclusions of this paper are valid for the broader area of chemical and process industries in general. The results demonstrate that well-interpretable and with-simple-structure inferential sensors can automatically be designed from the data stream in real time, which predict various process variables of interest. The proposed approach can be used as a basis for the development of a new generation of adaptive and evolving inferential sensors that can address the

  2. Adaptive sensor array algorithm for structural health monitoring of helmet

    NASA Astrophysics Data System (ADS)

    Zou, Xiaotian; Tian, Ye; Wu, Nan; Sun, Kai; Wang, Xingwei

    2011-04-01

    The adaptive neural network is a standard technique used in nonlinear system estimation and learning applications for dynamic models. In this paper, we introduced an adaptive sensor fusion algorithm for a helmet structure health monitoring system. The helmet structure health monitoring system is used to study the effects of ballistic/blast events on the helmet and human skull. Installed inside the helmet system, there is an optical fiber pressure sensors array. After implementing the adaptive estimation algorithm into helmet system, a dynamic model for the sensor array has been developed. The dynamic response characteristics of the sensor network are estimated from the pressure data by applying an adaptive control algorithm using artificial neural network. With the estimated parameters and position data from the dynamic model, the pressure distribution of the whole helmet can be calculated following the Bazier Surface interpolation method. The distribution pattern inside the helmet will be very helpful for improving helmet design to provide better protection to soldiers from head injuries.

  3. Sensor Web Dynamic Measurement Techniques and Adaptive Observing Strategies

    NASA Technical Reports Server (NTRS)

    Talabac, Stephen J.

    2004-01-01

    Sensor Web observing systems may have the potential to significantly improve our ability to monitor, understand, and predict the evolution of rapidly evolving, transient, or variable environmental features and events. This improvement will come about by integrating novel data collection techniques, new or improved instruments, emerging communications technologies and protocols, sensor mark-up languages, and interoperable planning and scheduling systems. In contrast to today's observing systems, "event-driven" sensor webs will synthesize real- or near-real time measurements and information from other platforms and then react by reconfiguring the platforms and instruments to invoke new measurement modes and adaptive observation strategies. Similarly, "model-driven" sensor webs will utilize environmental prediction models to initiate targeted sensor measurements or to use a new observing strategy. The sensor web concept contrasts with today's data collection techniques and observing system operations concepts where independent measurements are made by remote sensing and in situ platforms that do not share, and therefore cannot act upon, potentially useful complementary sensor measurement data and platform state information. This presentation describes NASA's view of event-driven and model-driven Sensor Webs and highlights several research and development activities at the Goddard Space Flight Center.

  4. Shack-Hartmann wavefront sensor with adaptive holographic lenslet array

    NASA Astrophysics Data System (ADS)

    Podanchuk, Dmytro V.; Dan'ko, Volodymyr P.; Goloborodko, Andrey A.; Sutyagina, Natalia S.

    2009-10-01

    The method of the dynamic range expansion of the Shack-Hartmann wavefront sensor is discussed. It's based on the use of nonlinear dual focus holographic lenslet arrays with the aberration precompensation. The data concerning the optical setup and the technique of adaptive lenslet array producing based on nonlinear holographic recording phenomenon are represented. On the example of spherical wavefronts it is shown, that the use of three lenslet arrays with different amount of the aberration precompensation allows expanding approximately in five times the dynamic range of the sensor four times greater with preserving the specified sensitivity in comparison with the corresponding refractive lenslet array.

  5. CleanFleet. Final report: Volume 8, fleet economics

    SciTech Connect

    1995-12-01

    The costs that face a fleet operator in implementing alternative motor fuels into fleet operations are examined. Five alternatives studied in the CleanFleet project are considered for choice of fuel: compressed natural gas, propane gas, California Phase 2 reformulated gasoline, M-85, and electricity. The cost assessment is built upon a list of thirteen cost factors grouped into the three categories: infrastructure costs, vehicle owning costs, and operating costs. Applicable taxes are included. A commonly used spreadsheet was adapted as a cost assessment tool. This tool was used in a case study to estimate potential costs to a typical fleet operator in package delivery service in the 1996 time frame. In addition, because electric cargo vans are unlikely to be available for the 1996 model year from original equipment manufacturers, the case study was extended to the 1998 time frame for the electric vans. Results of the case study are presented in cents per mile of vehicle travel for the fleet. Several options available to the fleet for implementing the fuels are examined.

  6. Noise-exploitation and adaptation in neuromorphic sensors

    NASA Astrophysics Data System (ADS)

    Hindo, Thamira; Chakrabartty, Shantanu

    2012-04-01

    Even though current micro-nano fabrication technology has reached integration levels where ultra-sensitive sensors can be fabricated, the sensing performance (resolution per joule) of synthetic systems are still orders of magnitude inferior to those observed in neurobiology. For example, the filiform hairs in crickets operate at fundamental limits of noise; auditory sensors in a parasitoid fly can overcome fundamental limitations to precisely localize ultra-faint acoustic signatures. Even though many of these biological marvels have served as inspiration for different types of neuromorphic sensors, the main focus these designs have been to faithfully replicate the biological functionalities, without considering the constructive role of "noise". In man-made sensors device and sensor noise are typically considered as a nuisance, where as in neurobiology "noise" has been shown to be a computational aid that enables biology to sense and operate at fundamental limits of energy efficiency and performance. In this paper, we describe some of the important noise-exploitation and adaptation principles observed in neurobiology and how they can be systematically used for designing neuromorphic sensors. Our focus will be on two types of noise-exploitation principles, namely, (a) stochastic resonance; and (b) noise-shaping, which are unified within our previously reported framework called Σ▵ learning. As a case-study, we describe the application of Σ▵ learning for the design of a miniature acoustic source localizer whose performance matches that of its biological counterpart(Ormia Ochracea).

  7. A multifunctional joint angle sensor with measurement adaptability.

    PubMed

    Quan, Wei; Wang, Hua; Liu, Datong

    2013-01-01

    The paper presents a multifunctional joint sensor with measurement adaptability for biological engineering applications, such as gait analysis, gesture recognition, etc. The adaptability is embodied in both static and dynamic environment measurements, both of body pose and in motion capture. Its multifunctional capabilities lay in its ability of simultaneous measurement of multiple degrees of freedom (MDOF) with a single sensor to reduce system complexity. The basic working mode enables 2DOF spatial angle measurement over big ranges and stands out for its applications on different joints of different individuals without recalibration. The optional advanced working mode enables an additional DOF measurement for various applications. By employing corrugated tube as the main body, the sensor is also characterized as flexible and wearable with less restraints. MDOF variations are converted to linear displacements of the sensing elements. The simple reconstruction algorithm and small outputs volume are capable of providing real-time angles and long-term monitoring. The performance assessment of the built prototype is promising enough to indicate the feasibility of the sensor. PMID:24217353

  8. Comparison of wavefront sensor models for simulation of adaptive optics.

    PubMed

    Wu, Zhiwen; Enmark, Anita; Owner-Petersen, Mette; Andersen, Torben

    2009-10-26

    The new generation of extremely large telescopes will have adaptive optics. Due to the complexity and cost of such systems, it is important to simulate their performance before construction. Most systems planned will have Shack-Hartmann wavefront sensors. Different mathematical models are available for simulation of such wavefront sensors. The choice of wavefront sensor model strongly influences computation time and simulation accuracy. We have studied the influence of three wavefront sensor models on performance calculations for a generic, adaptive optics (AO) system designed for K-band operation of a 42 m telescope. The performance of this AO system has been investigated both for reduced wavelengths and for reduced r(0) in the K band. The telescope AO system was designed for K-band operation, that is both the subaperture size and the actuator pitch were matched to a fixed value of r(0) in the K-band. We find that under certain conditions, such as investigating limiting guide star magnitude for large Strehl-ratios, a full model based on Fraunhofer propagation to the subimages is significantly more accurate. It does however require long computation times. The shortcomings of simpler models based on either direct use of average wavefront tilt over the subapertures for actuator control, or use of the average tilt to move a precalculated point spread function in the subimages are most pronounced for studies of system limitations to operating parameter variations. In the long run, efficient parallelization techniques may be developed to overcome the problem. PMID:19997286

  9. Wavefront sensors and algorithms for adaptive optical systems

    NASA Astrophysics Data System (ADS)

    Lukin, V. P.; Botygina, N. N.; Emaleev, O. N.; Konyaev, P. A.

    2010-07-01

    The results of recent works related to techniques and algorithms for wave-front (WF) measurement using Shack-Hartmann sensors show their high efficiency in solution of very different problems of applied optics. The goal of this paper was to develop a sensitive Shack-Hartmann sensor with high precision WF measurement capability on the base of modern technology of optical elements making and new efficient methods and computational algorithms of WF reconstruction. The Shack-Hartmann sensors sensitive to small WF aberrations are used for adaptive optical systems, compensating the wave distortions caused by atmospheric turbulence. A high precision Shack-Hartmann WF sensor has been developed on the basis of a low-aperture off-axis diffraction lens array. The device is capable of measuring WF slopes at array sub-apertures of size 640×640 μm with an error not exceeding 4.80 arcsec (0.15 pixel), which corresponds to the standard deviation equal to 0.017λ at the reconstructed WF with wavelength λ . Also the modification of this sensor for adaptive system of solar telescope using extended scenes as tracking objects, such as sunspot, pores, solar granulation and limb, is presented. The software package developed for the proposed WF sensors includes three algorithms of local WF slopes estimation (modified centroids, normalized cross-correlation and fast Fourierdemodulation), as well as three methods of WF reconstruction (modal Zernike polynomials expansion, deformable mirror response functions expansion and phase unwrapping), that can be selected during operation with accordance to the application.

  10. Adaptive Data Filtering of Inertial Sensors with Variable Bandwidth

    PubMed Central

    Alam, Mushfiqul; Rohac, Jan

    2015-01-01

    MEMS (micro-electro-mechanical system)-based inertial sensors, i.e., accelerometers and angular rate sensors, are commonly used as a cost-effective solution for the purposes of navigation in a broad spectrum of terrestrial and aerospace applications. These tri-axial inertial sensors form an inertial measurement unit (IMU), which is a core unit of navigation systems. Even if MEMS sensors have an advantage in their size, cost, weight and power consumption, they suffer from bias instability, noisy output and insufficient resolution. Furthermore, the sensor's behavior can be significantly affected by strong vibration when it operates in harsh environments. All of these constitute conditions require treatment through data processing. As long as the navigation solution is primarily based on using only inertial data, this paper proposes a novel concept in adaptive data pre-processing by using a variable bandwidth filtering. This approach utilizes sinusoidal estimation to continuously adapt the filtering bandwidth of the accelerometer's data in order to reduce the effects of vibration and sensor noise before attitude estimation is processed. Low frequency vibration generally limits the conditions under which the accelerometers can be used to aid the attitude estimation process, which is primarily based on angular rate data and, thus, decreases its accuracy. In contrast, the proposed pre-processing technique enables using accelerometers as an aiding source by effective data smoothing, even when they are affected by low frequency vibration. Verification of the proposed concept is performed on simulation and real-flight data obtained on an ultra-light aircraft. The results of both types of experiments confirm the suitability of the concept for inertial data pre-processing. PMID:25648711

  11. Adaptive data filtering of inertial sensors with variable bandwidth.

    PubMed

    Alam, Mushfiqul; Rohac, Jan

    2015-01-01

    MEMS (micro-electro-mechanical system)-based inertial sensors, i.e., accelerometers and angular rate sensors, are commonly used as a cost-effective solution for the purposes of navigation in a broad spectrum of terrestrial and aerospace applications. These tri-axial inertial sensors form an inertial measurement unit (IMU), which is a core unit of navigation systems. Even if MEMS sensors have an advantage in their size, cost, weight and power consumption, they suffer from bias instability, noisy output and insufficient resolution. Furthermore, the sensor's behavior can be significantly affected by strong vibration when it operates in harsh environments. All of these constitute conditions require treatment through data processing. As long as the navigation solution is primarily based on using only inertial data, this paper proposes a novel concept in adaptive data pre-processing by using a variable bandwidth filtering. This approach utilizes sinusoidal estimation to continuously adapt the filtering bandwidth of the accelerometer's data in order to reduce the effects of vibration and sensor noise before attitude estimation is processed. Low frequency vibration generally limits the conditions under which the accelerometers can be used to aid the attitude estimation process, which is primarily based on angular rate data and, thus, decreases its accuracy. In contrast, the proposed pre-processing technique enables using accelerometers as an aiding source by effective data smoothing, even when they are affected by low frequency vibration. Verification of the proposed concept is performed on simulation and real-flight data obtained on an ultra-light aircraft. The results of both types of experiments confirm the suitability of the concept for inertial data pre-processing. PMID:25648711

  12. Wavefront sensor and wavefront corrector matching in adaptive optics

    PubMed Central

    Dubra, Alfredo

    2016-01-01

    Matching wavefront correctors and wavefront sensors by minimizing the condition number and mean wavefront variance is proposed. The particular cases of two continuous-sheet deformable mirrors and a Shack-Hartmann wavefront sensor with square packing geometry are studied in the presence of photon noise, background noise and electronics noise. Optimal number of lenslets across each actuator are obtained for both deformable mirrors, and a simple experimental procedure for optimal alignment is described. The results show that high-performance adaptive optics can be achieved even with low cost off-the-shelf Shack-Hartmann arrays with lenslet spacing that do not necessarily match those of the wavefront correcting elements. PMID:19532513

  13. Adaptive wavefront sensor based on the Talbot phenomenon.

    PubMed

    Podanchuk, Dmytro V; Goloborodko, Andrey A; Kotov, Myhailo M; Kovalenko, Andrey V; Kurashov, Vitalij N; Dan'ko, Volodymyr P

    2016-04-20

    A new adaptive method of wavefront sensing is proposed and demonstrated. The method is based on the Talbot self-imaging effect, which is observed in an illuminating light beam with strong second-order aberration. Compensation of defocus and astigmatism is achieved with an appropriate choice of size of the rectangular unit cell of the diffraction grating, which is performed iteratively. A liquid-crystal spatial light modulator is used for this purpose. Self-imaging of rectangular grating in the astigmatic light beam is demonstrated experimentally. High-order aberrations are detected with respect to the compensated second-order aberration. The comparative results of wavefront sensing with a Shack-Hartmann sensor and the proposed sensor are adduced. PMID:27140122

  14. Adaptive Multichannel Radiation Sensors for Plant Parameter Monitoring

    NASA Astrophysics Data System (ADS)

    Mollenhauer, Hannes; Remmler, Paul; Schuhmann, Gudrun; Lausch, Angela; Merbach, Ines; Assing, Martin; Mollenhauer, Olaf; Dietrich, Peter; Bumberger, Jan

    2016-04-01

    Nutrients such as nitrogen are playing a key role in the plant life cycle. They are much needed for chlorophyll production and other plant cell components. Therefore, the crop yield is strongly affected by plant nutrient status. Due to the spatial and temporal variability of soil characteristics or swaying agricultural inputs the plant development varies within a field. Thus, the determination of these fluctuations in the plant development is valuable for a detection of stress conditions and optimization of fertilisation due to its high environmental and economic impact. Plant parameters play crucial roles in plant growth estimation and prediction since they are used as indicators of plant performance. Especially indices derived out of remote sensing techniques provide quantitative information about agricultural crops instantaneously, and above all, non-destructively. Due to the specific absorption of certain plant pigments, a characteristic spectral signature can be seen in the visible and IR part of the electromagnetic spectrum, known as narrow-band peaks. In an analogous manner, the presence and concentration of different nutrients cause a characteristic spectral signature. To this end, an adequate remote sensing monitoring concept is needed, considering heterogeneity and dynamic of the plant population and economical aspects. This work will present the development and field investigations of an inexpensive multichannel radiation sensor to observe the incoming and reflected specific parts or rather distinct wavelengths of the solar light spectrum on the crop and facilitate the determination of different plant indices. Based on the selected sensor wavelengths, the sensing device allows the detection of specific parameters, e.g. plant vitality, chlorophyll content or nitrogen content. Besides the improvement of the sensor characteristic, the simple wavelength adaption, and the price-performance ratio, the achievement of appropriate energy efficiency as well as a

  15. An adaptive technique for a redundant-sensor navigation system.

    NASA Technical Reports Server (NTRS)

    Chien, T.-T.

    1972-01-01

    An on-line adaptive technique is developed to provide a self-contained redundant-sensor navigation system with a capability to utilize its full potentiality in reliability and performance. This adaptive system is structured as a multistage stochastic process of detection, identification, and compensation. It is shown that the detection system can be effectively constructed on the basis of a design value, specified by mission requirements, of the unknown parameter in the actual system, and of a degradation mode in the form of a constant bias jump. A suboptimal detection system on the basis of Wald's sequential analysis is developed using the concept of information value and information feedback. The developed system is easily implemented, and demonstrates a performance remarkably close to that of the optimal nonlinear detection system. An invariant transformation is derived to eliminate the effect of nuisance parameters such that the ambiguous identification system can be reduced to a set of disjoint simple hypotheses tests. By application of a technique of decoupled bias estimation in the compensation system the adaptive system can be operated without any complicated reorganization.

  16. Self-adaptive calibration for staring infrared sensors

    NASA Astrophysics Data System (ADS)

    Kendall, William B.; Stocker, Alan D.

    1993-10-01

    This paper presents a new, self-adaptive technique for the correlation of non-uniformities (fixed-pattern noise) in high-density infrared focal-plane detector arrays. We have developed a new approach to non-uniformity correction in which we use multiple image frames of the scene itself, and take advantage of the aim-point wander caused by jitter, residual tracking errors, or deliberately induced motion. Such wander causes each detector in the array to view multiple scene elements, and each scene element to be viewed by multiple detectors. It is therefore possible to formulate (and solve) a set of simultaneous equations from which correction parameters can be computed for the detectors. We have tested our approach with actual images collected by the ARPA-sponsored MUSIC infrared sensor. For these tests we employed a 60-frame (0.75-second) sequence of terrain images for which an out-of-date calibration was deliberately used. The sensor was aimed at a point on the ground via an operator-assisted tracking system having a maximum aim point wander on the order of ten pixels. With these data, we were able to improve the calibration accuracy by a factor of approximately 100.

  17. Adaptive control of vibrissae-like mechanical sensors

    NASA Astrophysics Data System (ADS)

    Behn, Carsten

    2011-05-01

    This paper is a contribution to the modeling and the adaptive control of bio-inspired sensors which have the animal vibrissae as a paradigm. Mice and rats employ a sophisticated tactile sensory system to explore their environment in addition to their visual and auditory sense. Vibrissae in the mystical pad (region around the mouth) are used both passively to sense environmental influences (wind, objects) and actively to detect surface and object structures. Inspired by this particular version of tactile sense we consider the following three stages of a sensory system: perception, transduction and processing of information. We model this system in combining two existing mechanical models and obtain an uncertain nonlinear control system. An applied adaptive controller implements the ability of the animals to employ their vibrissae actively as well as passively. Numerical simulations show that the developed nonlinear model compensates noise signals and reacts strongly to sudden perturbations while guaranteeing a pre-specified control objective (working in active or passive mode).

  18. Adaptive learning of Multi-Sensor Integration techniques with genetic algorithms

    SciTech Connect

    Baker, J.E.

    1994-06-01

    This research focuses on automating the time-consuming process of developing and optimizing multi-sensor integration techniques. Our approach is currently based on adaptively learning how to exploit low-level image detail. Although this system is specifically designed to be both sensor and application domain independent, an empirical validation with actual multi-modal sensor data is presented.

  19. Evolutionary Adaptive Discovery of Phased Array Sensor Signal Identification

    SciTech Connect

    Timothy R. McJunkin; Milos Manic

    2011-05-01

    Tomography, used to create images of the internal properties and features of an object, from phased array ultasonics is improved through many sophisiticated methonds of post processing of data. One approach used to improve tomographic results is to prescribe the collection of more data, from different points of few so that data fusion might have a richer data set to work from. This approach can lead to rapid increase in the data needed to be stored and processed. It also does not necessarily lead to have the needed data. This article describes a novel approach to utilizing the data aquired as a basis for adapting the sensors focusing parameters to locate more precisely the features in the material: specifically, two evolutionary methods of autofocusing on a returned signal are coupled with the derivations of the forumulas for spatially locating the feature are given. Test results of the two novel methods of evolutionary based focusing (EBF) illustrate the improved signal strength and correction of the position of feature using the optimized focal timing parameters, called Focused Delay Identification (FoDI).

  20. A Phase-Shifting Zernike Wavefront Sensor for the Palomar P3K Adaptive Optics System

    NASA Technical Reports Server (NTRS)

    Wallace, J. Kent; Crawford, Sam; Loya, Frank; Moore, James

    2012-01-01

    A phase-shifting Zernike wavefront sensor has distinct advantages over other types of wavefront sensors. Chief among them are: 1) improved sensitivity to low-order aberrations and 2) efficient use of photons (hence reduced sensitivity to photon noise). We are in the process of deploying a phase-shifting Zernike wavefront sensor to be used with the realtime adaptive optics system for Palomar. Here we present the current state of the Zernike wavefront sensor to be integrated into the high-order adaptive optics system at Mount Palomar's Hale Telescope.

  1. Closed-loop adaptive optics using a CMOS image quality metric sensor

    NASA Astrophysics Data System (ADS)

    Ting, Chueh; Rayankula, Aditya; Giles, Michael K.; Furth, Paul M.

    2006-08-01

    When compared to a Shack-Hartmann sensor, a CMOS image sharpness sensor has the advantage of reduced complexity in a closed-loop adaptive optics system. It also has the potential to be implemented as a smart sensor using VLSI technology. In this paper, we present a novel adaptive optics testbed that uses a CMOS sharpness imager built in the New Mexico State University (NMSU) Electro-Optics Research Laboratory (EORL). The adaptive optics testbed, which includes a CMOS image quality metric sensor and a 37-channel deformable mirror, has the capability to rapidly compensate higher-order phase aberrations. An experimental performance comparison of the pinhole image sharpness feedback method and the CMOS imager is presented. The experimental data shows that the CMOS sharpness imager works well in a closed-loop adaptive optics system. Its overall performance is better than that of the pinhole method, and it has a fast response time.

  2. Computerized Fleet Maintenance.

    ERIC Educational Resources Information Center

    Cataldo, John J.

    1985-01-01

    The Computerized Fleet Maintenance (CFM) program of a New York school district has major component areas of garage operation, vehicle replacement, and fuel consumption. CFM detects high expenditures and provides the rationale for bus replacement. (MLF)

  3. Fleet DNA (Presentation)

    SciTech Connect

    Walkokwicz, K.; Duran, A.

    2014-06-01

    The Fleet DNA project objectives include capturing and quantifying drive cycle and technology variation for the multitude of medium- and heavy-duty vocations; providing a common data storage warehouse for medium- and heavy-duty vehicle fleet data across DOE activities and laboratories; and integrating existing DOE tools, models, and analyses to provide data-driven decision making capabilities. Fleet DNA advantages include: for Government - providing in-use data for standard drive cycle development, R&D, tech targets, and rule making; for OEMs - real-world usage datasets provide concrete examples of customer use profiles; for fleets - vocational datasets help illustrate how to maximize return on technology investments; for Funding Agencies - ways are revealed to optimize the impact of financial incentive offers; and for researchers -a data source is provided for modeling and simulation.

  4. NREL Fleet Analysis Toolkit

    2006-12-31

    The software analyzes large time-dependent data sets from fleets of vehicles and their fueling infrastructure to characterize performance metrics including efficiency, durability, fueling rates and usage patterns.

  5. Clean Fleet Final Report

    DOE Alternative Fuels and Advanced Vehicles Data Center

    ... &23; Crankshafts &23; Timing gears &23; Push rods &23; Stem and tip portions of the valves &23; Piston ... Accordingly, the CleanFleet program plan contained provisions for acquiring and analyzing ...

  6. Adaptive Control in the Presence of Simultaneous Sensor Bias and Actuator Failures

    NASA Technical Reports Server (NTRS)

    Joshi, Suresh M.

    2012-01-01

    The problem of simultaneously accommodating unknown sensor biases and unknown actuator failures in uncertain systems is considered in a direct model reference adaptive control (MRAC) setting for state tracking using state feedback. Sensor biases and actuator faults may be present at the outset or may occur at unknown instants of time during operation. A modified MRAC law is proposed, which combines sensor bias estimation with control gain adaptation for accommodation of sensor biases and actuator failures. This control law is shown to provide signal boundedness in the resulting system. For the case when an external asymptotically stable sensor bias estimator is available, an MRAC law is developed to accomplish asymptotic state tracking and signal boundedness. For a special case wherein biases are only present in the rate measurements and bias-free position measurements are available, an MRAC law is developed using a model-independent bias estimator, and is shown to provide asymptotic state tracking with signal boundedness.

  7. Real-time sensor mapping display for airborne imaging sensor test with the adaptive infrared imaging spectroradiometer (AIRIS)

    NASA Astrophysics Data System (ADS)

    Burton, Megan M.; Cruger, William E.; Gittins, Christopher; Kindle, Harry; Ricks, Timothy P.

    2005-11-01

    Captive flight testing (CFT) of sensors and seekers requires accurate data collection and display for sensor performance evaluation. The U.S. Army Redstone Technical Test Center (RTTC), in support of the U.S. Army Edgewood Chemical Biological Center (ECBC), has developed a data collection suite to facilitate airborne test of hyperspectral chemical/biological sensors. The data collection suite combines global positioning system (GPS) tracking, inertial measurement unit (IMU) data, accurate timing streams, and other test scenario information. This data collection suite also contains an advanced real-time display of aircraft and sensor field-of-view information. The latest evolution of this system has been used in support of the Adaptive InfraRed Imaging Spectroradiometer (AIRIS), currently under development by Physical Sciences Incorporated for ECBC. For this test, images from the AIRIS sensor were overlaid on a digitized background of the test area, with latencies of 1 second or less. Detects of surrogate chemicals were displayed and geo-referenced. Video overlay was accurate and reliable. This software suite offers great versatility in the display of imaging sensor data; support of future tests with the AIRIS sensor are planned as the system evolves.

  8. An adaptive Kalman filter approach for cardiorespiratory signal extraction and fusion of non-contacting sensors

    PubMed Central

    2014-01-01

    Background Extracting cardiorespiratory signals from non-invasive and non-contacting sensor arrangements, i.e. magnetic induction sensors, is a challenging task. The respiratory and cardiac signals are mixed on top of a large and time-varying offset and are likely to be disturbed by measurement noise. Basic filtering techniques fail to extract relevant information for monitoring purposes. Methods We present a real-time filtering system based on an adaptive Kalman filter approach that separates signal offsets, respiratory and heart signals from three different sensor channels. It continuously estimates respiration and heart rates, which are fed back into the system model to enhance performance. Sensor and system noise covariance matrices are automatically adapted to the aimed application, thus improving the signal separation capabilities. We apply the filtering to two different subjects with different heart rates and sensor properties and compare the results to the non-adaptive version of the same Kalman filter. Also, the performance, depending on the initialization of the filters, is analyzed using three different configurations ranging from best to worst case. Results Extracted data are compared with reference heart rates derived from a standard pulse-photoplethysmographic sensor and respiration rates from a flowmeter. In the worst case for one of the subjects the adaptive filter obtains mean errors (standard deviations) of -0.2 min −1 (0.3 min −1) and -0.7 bpm (1.7 bpm) (compared to -0.2 min −1 (0.4 min −1) and 42.0 bpm (6.1 bpm) for the non-adaptive filter) for respiration and heart rate, respectively. In bad conditions the heart rate is only correctly measurable when the Kalman matrices are adapted to the target sensor signals. Also, the reduced mean error between the extracted offset and the raw sensor signal shows that adapting the Kalman filter continuously improves the ability to separate the desired signals from the raw sensor data. The average

  9. Fleets of enduring drones to probe atmospheric phenomena with clouds

    NASA Astrophysics Data System (ADS)

    Lacroix, Simon; Roberts, Greg; Benard, Emmanuel; Bronz, Murat; Burnet, Frédéric; Bouhoubeiny, Elkhedim; Condomines, Jean-Philippe; Doll, Carsten; Hattenberger, Gautier; Lamraoui, Fayçal; Renzaglia, Alessandro; Reymann, Christophe

    2016-04-01

    A full spatio-temporal four-dimensional characterization of the microphysics and dynamics of cloud formation including the onset of precipitation has never been reached. Such a characterization would yield a better understanding of clouds, e.g. to assess the dominant mixing mechanism and the main source of cloudy updraft dilution. It is the sampling strategy that matters: fully characterizing the evolution over time of the various parameters (P, T, 3D wind, liquid water content, aerosols...) within a cloud volume requires dense spatial sampling for durations of the order of one hour. A fleet of autonomous lightweight UAVs that coordinate themselves in real-time as an intelligent network can fulfill this purpose. The SkyScanner project targets the development of a fleet of autonomous UAVs to adaptively sample cumuli, so as to provide relevant data to address long standing questions in atmospheric science. It mixes basic researches and experimental developments, and gathers scientists in UAV conception, in optimal flight control, in intelligent cooperative behaviors, and of course atmospheric scientists. Two directions of researches are explored: optimal UAV conception and control, and optimal control of a fleet of UAVs. The design of UAVs for atmospheric science involves the satisfaction of trade-offs between payload, endurance, ease of deployment... A rational conception scheme that integrates the constraints to optimize a series of criteria, in particular energy consumption, would yield the definition of efficient UAVs. This requires a fine modeling of each involved sub-system and phenomenon, from the motor/propeller efficiency to the aerodynamics at small scale, including the flight control algorithms. The definition of mission profiles is also essential, considering the aerodynamics of clouds, to allow energy harvesting schemes that exploit thermals or gusts. The conception also integrates specific sensors, in particular wind sensor, for which classic

  10. An adaptive distributed data aggregation based on RCPC for wireless sensor networks

    NASA Astrophysics Data System (ADS)

    Hua, Guogang; Chen, Chang Wen

    2006-05-01

    One of the most important design issues in wireless sensor networks is energy efficiency. Data aggregation has significant impact on the energy efficiency of the wireless sensor networks. With massive deployment of sensor nodes and limited energy supply, data aggregation has been considered as an essential paradigm for data collection in sensor networks. Recently, distributed source coding has been demonstrated to possess several advantages in data aggregation for wireless sensor networks. Distributed source coding is able to encode sensor data with lower bit rate without direct communication among sensor nodes. To ensure reliable and high throughput transmission with the aggregated data, we proposed in this research a progressive transmission and decoding of Rate-Compatible Punctured Convolutional (RCPC) coded data aggregation with distributed source coding. Our proposed 1/2 RSC codes with Viterbi algorithm for distributed source coding are able to guarantee that, even without any correlation between the data, the decoder can always decode the data correctly without wasting energy. The proposed approach achieves two aspects in adaptive data aggregation for wireless sensor networks. First, the RCPC coding facilitates adaptive compression corresponding to the correlation of the sensor data. When the data correlation is high, higher compression ration can be achieved. Otherwise, lower compression ratio will be achieved. Second, the data aggregation is adaptively accumulated. There is no waste of energy in the transmission; even there is no correlation among the data, the energy consumed is at the same level as raw data collection. Experimental results have shown that the proposed distributed data aggregation based on RCPC is able to achieve high throughput and low energy consumption data collection for wireless sensor networks

  11. Sparse Downscaling and Adaptive Fusion of Multi-sensor Precipitation

    NASA Astrophysics Data System (ADS)

    Ebtehaj, M.; Foufoula, E.

    2011-12-01

    The past decades have witnessed a remarkable emergence of new sources of multiscale multi-sensor precipitation data including data from global spaceborne active and passive sensors, regional ground based weather surveillance radars and local rain-gauges. Resolution enhancement of remotely sensed rainfall and optimal integration of multi-sensor data promise a posteriori estimates of precipitation fluxes with increased accuracy and resolution to be used in hydro-meteorological applications. In this context, new frameworks are proposed for resolution enhancement and multiscale multi-sensor precipitation data fusion, which capitalize on two main observations: (1) sparseness of remotely sensed precipitation fields in appropriately chosen transformed domains, (e.g., in wavelet space) which promotes the use of the newly emerged theory of sparse representation and compressive sensing for resolution enhancement; (2) a conditionally Gaussian Scale Mixture (GSM) parameterization in the wavelet domain which allows exploiting the efficient linear estimation methodologies, while capturing the non-Gaussian data structure of rainfall. The proposed methodologies are demonstrated using a data set of coincidental observations of precipitation reflectivity images by the spaceborne precipitation radar (PR) aboard the Tropical Rainfall Measurement Mission (TRMM) satellite and ground-based NEXRAD weather surveillance Doppler radars. Uniqueness and stability of the solution, capturing non-Gaussian singular structure of rainfall, reduced uncertainty of estimation and efficiency of computation are the main advantages of the proposed methodologies over the commonly used standard Gaussian techniques.

  12. Carbon fiber-ZnO nanowire hybrid structures for flexible and adaptable strain sensors

    NASA Astrophysics Data System (ADS)

    Liao, Qingliang; Mohr, Markus; Zhang, Xiaohui; Zhang, Zheng; Zhang, Yue; Fecht, Hans-Jörg

    2013-11-01

    We report the flexible piezotronic strain sensors fabricated using carbon fiber-ZnO nanowire hybrid structures by a novel and reliable method. The I-V characteristic of the sensor shows high sensitivity to external strain due to the change in Schottky barrier height (SBH), which has a linear relationship with strain. This fabricated strain sensor has a quick, real-time current response under both static and dynamic mechanical loads. The change in SBH resulted from the strain-induced piezoelectric potential is investigated by band gap theory. In this work we develop a new feasible method to fabricate a flexible strain sensor within the fabric adapted to textile structures, able to measure their strain.We report the flexible piezotronic strain sensors fabricated using carbon fiber-ZnO nanowire hybrid structures by a novel and reliable method. The I-V characteristic of the sensor shows high sensitivity to external strain due to the change in Schottky barrier height (SBH), which has a linear relationship with strain. This fabricated strain sensor has a quick, real-time current response under both static and dynamic mechanical loads. The change in SBH resulted from the strain-induced piezoelectric potential is investigated by band gap theory. In this work we develop a new feasible method to fabricate a flexible strain sensor within the fabric adapted to textile structures, able to measure their strain. Electronic supplementary information (ESI) available. See DOI: 10.1039/c3nr03536k

  13. Adaptation of sensor morphology: an integrative view of perception from biologically inspired robotics perspective.

    PubMed

    Iida, Fumiya; Nurzaman, Surya G

    2016-08-01

    Sensor morphology, the morphology of a sensing mechanism which plays a role of shaping the desired response from physical stimuli from surroundings to generate signals usable as sensory information, is one of the key common aspects of sensing processes. This paper presents a structured review of researches on bioinspired sensor morphology implemented in robotic systems, and discusses the fundamental design principles. Based on literature review, we propose two key arguments: first, owing to its synthetic nature, biologically inspired robotics approach is a unique and powerful methodology to understand the role of sensor morphology and how it can evolve and adapt to its task and environment. Second, a consideration of an integrative view of perception by looking into multidisciplinary and overarching mechanisms of sensor morphology adaptation across biology and engineering enables us to extract relevant design principles that are important to extend our understanding of the unfinished concepts in sensing and perception. PMID:27499843

  14. Adaptive Yaw Rate Aware Sensor Wakeup Schemes Protocol (A-YAP) for Target Prediction and Tracking in Sensor Networks

    NASA Astrophysics Data System (ADS)

    Raza, Muhammad Taqi; Mir, Zeeshan Hameed; Akbar, Ali Hammad; Yoo, Seung-Wha; Kim, Ki-Hyung

    Target tracking is one of the key applications of Wireless Sensor Networks (WSNs) that forms basis for numerous other applications. The overall procedures of target tracking involve target detection, localization, and tracking. Because of the WSNs' resource constraints (especially energy), it is highly desired that target tracking should be done by involving as less number of sensor nodes as possible. Due to the uncertain behavior of the target and resulting mobility patterns, this goal becomes harder to achieve without predicting the future locations of the target. The presence of a prediction mechanism may allow the activation of only the relevant sensors along the future course, before actually the target reaches the future location. This prior activation contributes to increasing the overall sensor networks lifetime by letting non-relevant nodes sleep. In this paper, first, we introduce a Yaw rate aware sensor wAkeup Protocol (YAP) for the prediction of future target locations. Second, we present improvements on the YAP design through the incorporation of adaptability. The proposed schemes are distributive in nature, and select relevant sensors to determine the target track. The performance of YAP and A-YAP is also discussed on different mobility patterns, which confirms the efficacy of the algorithm.

  15. A unique approach to the development of adaptive sensor systems for future spacecraft

    NASA Technical Reports Server (NTRS)

    Schappell, R. T.; Tietz, J. C.; Sivertson, W. E.; Wilson, R. G.

    1979-01-01

    In the Shuttle era, it should be possible to develop adaptive remote sensor systems serving more directly specific researcher and user needs and at the same time alleviating the data management problem via intelligent sensor capabilities. The present paper provides a summary of such an approach, wherein specific capabilities have been developed for future global monitoring applications. A detailed description of FILE-I (Feature Identification and Location Experiment) is included along with a summary of future experiments currently under development.

  16. Adaptive routing for dynamic on-body wireless sensor networks.

    PubMed

    Maskooki, Arash; Soh, Cheong Boon; Gunawan, Erry; Low, Kay Soon

    2015-03-01

    Energy is scarce in mobile computing devices including wearable and implantable devices in a wireless body area network. In this paper, an adaptive routing protocol is developed and analyzed which minimizes the energy cost per bit of information by using the channel information to choose the best strategy to route data. In this approach, the source node will switch between direct and relayed communication based on the quality of the link and will use the relay only if the channel quality is below a certain threshold. The mathematical model is then validated through simulations which shows that the adaptive routing strategy can improve energy efficiency significantly compared with existing methods. PMID:24686306

  17. Nanoparticle-dispersed metamaterial sensors for adaptive coded aperture imaging applications

    NASA Astrophysics Data System (ADS)

    Nehmetallah, Georges; Banerjee, Partha; Aylo, Rola; Rogers, Stanley

    2011-09-01

    We propose tunable single-layer and multi-layer (periodic and with defect) structures comprising nanoparticle dispersed metamaterials in suitable hosts, including adaptive coded aperture constructs, for possible Adaptive Coded Aperture Imaging (ACAI) applications such as in microbolometry, pressure/temperature sensors, and directed energy transfer, over a wide frequency range, from visible to terahertz. These structures are easy to fabricate, are low-cost and tunable, and offer enhanced functionality, such as perfect absorption (in the case of bolometry) and low cross-talk (for sensors). Properties of the nanoparticle dispersed metamaterial are determined using effective medium theory.

  18. Secure Adaptive Topology Control for Wireless Ad-Hoc Sensor Networks

    PubMed Central

    Hsueh, Ching-Tsung; Li, Yu-Wei; Wen, Chih-Yu; Ouyang, Yen-Chieh

    2010-01-01

    This paper presents a secure decentralized clustering algorithm for wireless ad-hoc sensor networks. The algorithm operates without a centralized controller, operates asynchronously, and does not require that the location of the sensors be known a priori. Based on the cluster-based topology, secure hierarchical communication protocols and dynamic quarantine strategies are introduced to defend against spam attacks, since this type of attacks can exhaust the energy of sensor nodes and will shorten the lifetime of a sensor network drastically. By adjusting the threshold of infected percentage of the cluster coverage, our scheme can dynamically coordinate the proportion of the quarantine region and adaptively achieve the cluster control and the neighborhood control of attacks. Simulation results show that the proposed approach is feasible and cost effective for wireless sensor networks. PMID:22205866

  19. Adaptive Preheating Duration Control for Low-Power Ambient Air Quality Sensor Networks

    PubMed Central

    Baek, Yoonchul; Atiq, Mahin K.; Kim, Hyung Seok

    2014-01-01

    Ceramic gas sensors used for measuring ambient air quality have features suitable for practical applications such as healthcare and air quality management, but have a major drawback—large power consumption to preheat the sensor for accurate measurements. In this paper; the adaptive preheating duration control (APC) method is proposed to reduce the power consumption of ambient air quality sensor networks. APC reduces the duration of unnecessary preheating, thereby alleviating power consumption. Furthermore, the APC can allow systems to meet user requirements such as accuracy and periodicity factor when detecting the concentration of a target gas. A performance evaluation of the power consumption of gas sensors is conducted with various user requirements and factors that affect the preheating duration of the gas sensor. This shows that the power consumption of the APC is lower than that of continuous power supply methods and constant power supply/cutoff methods. PMID:24658619

  20. Adaptive sensor placement for target tracking in the presence of uncertainties

    NASA Astrophysics Data System (ADS)

    Punithakumar, Kumaradevan; Kirubarajan, Thiagalingam; Hernandez, Marcel L.

    2003-12-01

    Recently a general framework for sensor resource management, which has been shown to allow efficient and effective utilization of a multisensor system was introduced in5. The basis of this technique is to use the Posterior Cramer-Rao Lower Bound (PCRLB) to quantify and control the optimal achievable accuracy of target state estimation. In the current paper we extend this framework by addressing the issues of imperfect sensor placement and uncertain sensor movement (e.g., sensor drift). In contrast the previous work considered only the case where the sensor location is known exactly. The crucial consideration is then how these two forms of uncertainty affect the sensor management strategy. If unaccounted for, these uncertainties will render the output of the resource manager useless. We adjust the PCRLB to account for sensor location uncertainty, and we also allow for measurement origin uncertainty (missed target originated detections and false alarms). The work is motivated by the problem of tracking a submarine by adaptively deploying sonobuoys from a helicopter. Simulation results are presented to show the advantages of accounting for sensor location uncertainty within this focal domain of anti-submarine warfare. The same technique can be used for tracking using unattended ground sensors (UGS) or unmanned aerial vehicles (UAV).

  1. Adaptive sensor placement for target tracking in the presence of uncertainties

    NASA Astrophysics Data System (ADS)

    Punithakumar, Kumaradevan; Kirubarajan, Thiagalingam; Hernandez, Marcel L.

    2004-01-01

    Recently a general framework for sensor resource management, which has been shown to allow efficient and effective utilization of a multisensor system was introduced in5. The basis of this technique is to use the Posterior Cramer-Rao Lower Bound (PCRLB) to quantify and control the optimal achievable accuracy of target state estimation. In the current paper we extend this framework by addressing the issues of imperfect sensor placement and uncertain sensor movement (e.g., sensor drift). In contrast the previous work considered only the case where the sensor location is known exactly. The crucial consideration is then how these two forms of uncertainty affect the sensor management strategy. If unaccounted for, these uncertainties will render the output of the resource manager useless. We adjust the PCRLB to account for sensor location uncertainty, and we also allow for measurement origin uncertainty (missed target originated detections and false alarms). The work is motivated by the problem of tracking a submarine by adaptively deploying sonobuoys from a helicopter. Simulation results are presented to show the advantages of accounting for sensor location uncertainty within this focal domain of anti-submarine warfare. The same technique can be used for tracking using unattended ground sensors (UGS) or unmanned aerial vehicles (UAV).

  2. Adaptive feature annotation for large video sensor networks

    NASA Astrophysics Data System (ADS)

    Cai, Yang; Bunn, Andrew; Liang, Peter; Yang, Bing

    2013-10-01

    We present an adaptive feature extraction and annotation algorithm for articulating traffic events from surveillance cameras. We use approximate median filter for moving object detection, motion energy image and convex hull for lane detection, and adaptive proportion models for vehicle classification. It is found that our approach outperforms three-dimensional modeling and scale-independent feature transformation algorithms in terms of robustness. The multiresolution-based video codec algorithm enables a quality-of-service-aware video streaming according to the data traffic. Furthermore, our empirical data shows that it is feasible to use the metadata to facilitate the real-time communication between an infrastructure and a vehicle for safer and more efficient traffic control.

  3. Adaptive Sampling for Learning Gaussian Processes Using Mobile Sensor Networks

    PubMed Central

    Xu, Yunfei; Choi, Jongeun

    2011-01-01

    This paper presents a novel class of self-organizing sensing agents that adaptively learn an anisotropic, spatio-temporal Gaussian process using noisy measurements and move in order to improve the quality of the estimated covariance function. This approach is based on a class of anisotropic covariance functions of Gaussian processes introduced to model a broad range of spatio-temporal physical phenomena. The covariance function is assumed to be unknown a priori. Hence, it is estimated by the maximum a posteriori probability (MAP) estimator. The prediction of the field of interest is then obtained based on the MAP estimate of the covariance function. An optimal sampling strategy is proposed to minimize the information-theoretic cost function of the Fisher Information Matrix. Simulation results demonstrate the effectiveness and the adaptability of the proposed scheme. PMID:22163785

  4. Pliable Cognitive MAC for Heterogeneous Adaptive Cognitive Radio Sensor Networks.

    PubMed

    Al-Medhwahi, Mohammed; Hashim, Fazirulhisyam; Ali, Borhanuddin Mohd; Sali, Aduwati

    2016-01-01

    The rapid expansion of wireless monitoring and surveillance applications in several domains reinforces the trend of exploiting emerging technologies such as the cognitive radio. However, these technologies have to adjust their working concepts to consider the common characteristics of conventional wireless sensor networks (WSNs). The cognitive radio sensor network (CRSN), still an immature technology, has to deal with new networks that might have different types of data, traffic patterns, or quality of service (QoS) requirements. In this paper, we design and model a new cognitive radio-based medium access control (MAC) algorithm dealing with the heterogeneous nature of the developed networks in terms of either the traffic pattern or the required QoS for the node applications. The proposed algorithm decreases the consumed power on several fronts, provides satisfactory levels of latency and spectrum utilization with efficient scheduling, and manages the radio resources for various traffic conditions. An intensive performance evaluation is conducted to study the impact of key parameters such as the channel idle time length, node density, and the number of available channels. The performance evaluation of the proposed algorithm shows a better performance than the comparable protocols. Moreover, the results manifest that the proposed algorithm is suitable for real time monitoring applications. PMID:27257964

  5. Pliable Cognitive MAC for Heterogeneous Adaptive Cognitive Radio Sensor Networks

    PubMed Central

    Ali, Borhanuddin Mohd; Sali, Aduwati

    2016-01-01

    The rapid expansion of wireless monitoring and surveillance applications in several domains reinforces the trend of exploiting emerging technologies such as the cognitive radio. However, these technologies have to adjust their working concepts to consider the common characteristics of conventional wireless sensor networks (WSNs). The cognitive radio sensor network (CRSN), still an immature technology, has to deal with new networks that might have different types of data, traffic patterns, or quality of service (QoS) requirements. In this paper, we design and model a new cognitive radio-based medium access control (MAC) algorithm dealing with the heterogeneous nature of the developed networks in terms of either the traffic pattern or the required QoS for the node applications. The proposed algorithm decreases the consumed power on several fronts, provides satisfactory levels of latency and spectrum utilization with efficient scheduling, and manages the radio resources for various traffic conditions. An intensive performance evaluation is conducted to study the impact of key parameters such as the channel idle time length, node density, and the number of available channels. The performance evaluation of the proposed algorithm shows a better performance than the comparable protocols. Moreover, the results manifest that the proposed algorithm is suitable for real time monitoring applications. PMID:27257964

  6. Ferment in the Fleet.

    ERIC Educational Resources Information Center

    Ludwigson, John

    1980-01-01

    The future of the academic oceanographic fleet is discussed. The focus of the controversy surrounding the ships appears to be their size and fuel efficiency. Budget constraints and various ways in which to schedule ships for researchers are the primary concerns. (SA)

  7. Wavefront detection method of a single-sensor based adaptive optics system.

    PubMed

    Wang, Chongchong; Hu, Lifa; Xu, Huanyu; Wang, Yukun; Li, Dayu; Wang, Shaoxin; Mu, Quanquan; Yang, Chengliang; Cao, Zhaoliang; Lu, Xinghai; Xuan, Li

    2015-08-10

    In adaptive optics system (AOS) for optical telescopes, the reported wavefront sensing strategy consists of two parts: a specific sensor for tip-tilt (TT) detection and another wavefront sensor for other distortions detection. Thus, a part of incident light has to be used for TT detection, which decreases the light energy used by wavefront sensor and eventually reduces the precision of wavefront correction. In this paper, a single Shack-Hartmann wavefront sensor based wavefront measurement method is presented for both large amplitude TT and other distortions' measurement. Experiments were performed for testing the presented wavefront method and validating the wavefront detection and correction ability of the single-sensor based AOS. With adaptive correction, the root-mean-square of residual TT was less than 0.2 λ, and a clear image was obtained in the lab. Equipped on a 1.23-meter optical telescope, the binary stars with angle distance of 0.6″ were clearly resolved using the AOS. This wavefront measurement method removes the separate TT sensor, which not only simplifies the AOS but also saves light energy for subsequent wavefront sensing and imaging, and eventually improves the detection and imaging capability of the AOS. PMID:26367988

  8. Adaptive pulsed laser line extraction for terrain reconstruction using a dynamic vision sensor

    PubMed Central

    Brandli, Christian; Mantel, Thomas A.; Hutter, Marco; Höpflinger, Markus A.; Berner, Raphael; Siegwart, Roland; Delbruck, Tobi

    2014-01-01

    Mobile robots need to know the terrain in which they are moving for path planning and obstacle avoidance. This paper proposes the combination of a bio-inspired, redundancy-suppressing dynamic vision sensor (DVS) with a pulsed line laser to allow fast terrain reconstruction. A stable laser stripe extraction is achieved by exploiting the sensor's ability to capture the temporal dynamics in a scene. An adaptive temporal filter for the sensor output allows a reliable reconstruction of 3D terrain surfaces. Laser stripe extractions up to pulsing frequencies of 500 Hz were achieved using a line laser of 3 mW at a distance of 45 cm using an event-based algorithm that exploits the sparseness of the sensor output. As a proof of concept, unstructured rapid prototype terrain samples have been successfully reconstructed with an accuracy of 2 mm. PMID:24478619

  9. Fiber Bragg grating dynamic strain sensor using an adaptive reflective semiconductor optical amplifier source.

    PubMed

    Wei, Heming; Tao, Chuanyi; Zhu, Yinian; Krishnaswamy, Sridhar

    2016-04-01

    In this paper, a reflective semiconductor optical amplifier (RSOA) is configured to demodulate dynamic spectral shifts of a fiber Bragg grating (FBG) dynamic strain sensor. The FBG sensor and the RSOA source form an adaptive fiber cavity laser. As the reflective spectrum of the FBG sensor changes due to dynamic strains, the wavelength of the laser output shifts accordingly, which is subsequently converted into a corresponding phase shift and demodulated by an unbalanced Michelson interferometer. Due to the short transition time of the RSOA, the RSOA-FBG cavity can respond to dynamic strains at high frequencies extending to megahertz. A demodulator using a PID controller is used to compensate for low-frequency drifts induced by temperature and large quasi-static strains. As the sensitivity of the demodulator is a function of the optical path difference and the FBG spectral width, optimal parameters to obtain high sensitivity are presented. Multiplexing to demodulate multiple FBG sensors is also discussed. PMID:27139682

  10. Communal Sensor Network for Adaptive Noise Reduction in Aircraft Engine Nacelles

    NASA Technical Reports Server (NTRS)

    Jones, Kennie H.; Nark, Douglas M.; Jones, Michael G.

    2011-01-01

    Emergent behavior, a subject of much research in biology, sociology, and economics, is a foundational element of Complex Systems Science and is apropos in the design of sensor network systems. To demonstrate engineering for emergent behavior, a novel approach in the design of a sensor/actuator network is presented maintaining optimal noise attenuation as an adaptation to changing acoustic conditions. Rather than use the conventional approach where sensors are managed by a central controller, this new paradigm uses a biomimetic model where sensor/actuators cooperate as a community of autonomous organisms, sharing with neighbors to control impedance based on local information. From the combination of all individual actions, an optimal attenuation emerges for the global system.

  11. Adaptive pulsed laser line extraction for terrain reconstruction using a dynamic vision sensor.

    PubMed

    Brandli, Christian; Mantel, Thomas A; Hutter, Marco; Höpflinger, Markus A; Berner, Raphael; Siegwart, Roland; Delbruck, Tobi

    2013-01-01

    Mobile robots need to know the terrain in which they are moving for path planning and obstacle avoidance. This paper proposes the combination of a bio-inspired, redundancy-suppressing dynamic vision sensor (DVS) with a pulsed line laser to allow fast terrain reconstruction. A stable laser stripe extraction is achieved by exploiting the sensor's ability to capture the temporal dynamics in a scene. An adaptive temporal filter for the sensor output allows a reliable reconstruction of 3D terrain surfaces. Laser stripe extractions up to pulsing frequencies of 500 Hz were achieved using a line laser of 3 mW at a distance of 45 cm using an event-based algorithm that exploits the sparseness of the sensor output. As a proof of concept, unstructured rapid prototype terrain samples have been successfully reconstructed with an accuracy of 2 mm. PMID:24478619

  12. An Energy Aware Adaptive Sampling Algorithm for Energy Harvesting WSN with Energy Hungry Sensors

    PubMed Central

    Srbinovski, Bruno; Magno, Michele; Edwards-Murphy, Fiona; Pakrashi, Vikram; Popovici, Emanuel

    2016-01-01

    Wireless sensor nodes have a limited power budget, though they are often expected to be functional in the field once deployed for extended periods of time. Therefore, minimization of energy consumption and energy harvesting technology in Wireless Sensor Networks (WSN) are key tools for maximizing network lifetime, and achieving self-sustainability. This paper proposes an energy aware Adaptive Sampling Algorithm (ASA) for WSN with power hungry sensors and harvesting capabilities, an energy management technique that can be implemented on any WSN platform with enough processing power to execute the proposed algorithm. An existing state-of-the-art ASA developed for wireless sensor networks with power hungry sensors is optimized and enhanced to adapt the sampling frequency according to the available energy of the node. The proposed algorithm is evaluated using two in-field testbeds that are supplied by two different energy harvesting sources (solar and wind). Simulation and comparison between the state-of-the-art ASA and the proposed energy aware ASA (EASA) in terms of energy durability are carried out using in-field measured harvested energy (using both wind and solar sources) and power hungry sensors (ultrasonic wind sensor and gas sensors). The simulation results demonstrate that using ASA in combination with an energy aware function on the nodes can drastically increase the lifetime of a WSN node and enable self-sustainability. In fact, the proposed EASA in conjunction with energy harvesting capability can lead towards perpetual WSN operation and significantly outperform the state-of-the-art ASA. PMID:27043559

  13. An Energy Aware Adaptive Sampling Algorithm for Energy Harvesting WSN with Energy Hungry Sensors.

    PubMed

    Srbinovski, Bruno; Magno, Michele; Edwards-Murphy, Fiona; Pakrashi, Vikram; Popovici, Emanuel

    2016-01-01

    Wireless sensor nodes have a limited power budget, though they are often expected to be functional in the field once deployed for extended periods of time. Therefore, minimization of energy consumption and energy harvesting technology in Wireless Sensor Networks (WSN) are key tools for maximizing network lifetime, and achieving self-sustainability. This paper proposes an energy aware Adaptive Sampling Algorithm (ASA) for WSN with power hungry sensors and harvesting capabilities, an energy management technique that can be implemented on any WSN platform with enough processing power to execute the proposed algorithm. An existing state-of-the-art ASA developed for wireless sensor networks with power hungry sensors is optimized and enhanced to adapt the sampling frequency according to the available energy of the node. The proposed algorithm is evaluated using two in-field testbeds that are supplied by two different energy harvesting sources (solar and wind). Simulation and comparison between the state-of-the-art ASA and the proposed energy aware ASA (EASA) in terms of energy durability are carried out using in-field measured harvested energy (using both wind and solar sources) and power hungry sensors (ultrasonic wind sensor and gas sensors). The simulation results demonstrate that using ASA in combination with an energy aware function on the nodes can drastically increase the lifetime of a WSN node and enable self-sustainability. In fact, the proposed EASA in conjunction with energy harvesting capability can lead towards perpetual WSN operation and significantly outperform the state-of-the-art ASA. PMID:27043559

  14. Adaptive sensing and optimal power allocation for wireless video sensors with sigma-delta imager.

    PubMed

    Marijan, Malisa; Demirkol, Ilker; Maricić I, Danijel; Sharma, Gaurav; Ignjatovi, Zeljko

    2010-10-01

    We consider optimal power allocation for wireless video sensors (WVSs), including the image sensor subsystem in the system analysis. By assigning a power-rate-distortion (P-R-D) characteristic for the image sensor, we build a comprehensive P-R-D optimization framework for WVSs. For a WVS node operating under a power budget, we propose power allocation among the image sensor, compression, and transmission modules, in order to minimize the distortion of the video reconstructed at the receiver. To demonstrate the proposed optimization method, we establish a P-R-D model for an image sensor based upon a pixel level sigma-delta (Σ∆) image sensor design that allows investigation of the tradeoff between the bit depth of the captured images and spatio-temporal characteristics of the video sequence under the power constraint. The optimization results obtained in this setting confirm that including the image sensor in the system optimization procedure can improve the overall video quality under power constraint and prolong the lifetime of the WVSs. In particular, when the available power budget for a WVS node falls below a threshold, adaptive sensing becomes necessary to ensure that the node communicates useful information about the video content while meeting its power budget. PMID:20551000

  15. Adaptive Particle Filter for Nonparametric Estimation with Measurement Uncertainty in Wireless Sensor Networks.

    PubMed

    Li, Xiaofan; Zhao, Yubin; Zhang, Sha; Fan, Xiaopeng

    2016-01-01

    Particle filters (PFs) are widely used for nonlinear signal processing in wireless sensor networks (WSNs). However, the measurement uncertainty makes the WSN observations unreliable to the actual case and also degrades the estimation accuracy of the PFs. In addition to the algorithm design, few works focus on improving the likelihood calculation method, since it can be pre-assumed by a given distribution model. In this paper, we propose a novel PF method, which is based on a new likelihood fusion method for WSNs and can further improve the estimation performance. We firstly use a dynamic Gaussian model to describe the nonparametric features of the measurement uncertainty. Then, we propose a likelihood adaptation method that employs the prior information and a belief factor to reduce the measurement noise. The optimal belief factor is attained by deriving the minimum Kullback-Leibler divergence. The likelihood adaptation method can be integrated into any PFs, and we use our method to develop three versions of adaptive PFs for a target tracking system using wireless sensor network. The simulation and experimental results demonstrate that our likelihood adaptation method has greatly improved the estimation performance of PFs in a high noise environment. In addition, the adaptive PFs are highly adaptable to the environment without imposing computational complexity. PMID:27249002

  16. Adaptive Particle Filter for Nonparametric Estimation with Measurement Uncertainty in Wireless Sensor Networks

    PubMed Central

    Li, Xiaofan; Zhao, Yubin; Zhang, Sha; Fan, Xiaopeng

    2016-01-01

    Particle filters (PFs) are widely used for nonlinear signal processing in wireless sensor networks (WSNs). However, the measurement uncertainty makes the WSN observations unreliable to the actual case and also degrades the estimation accuracy of the PFs. In addition to the algorithm design, few works focus on improving the likelihood calculation method, since it can be pre-assumed by a given distribution model. In this paper, we propose a novel PF method, which is based on a new likelihood fusion method for WSNs and can further improve the estimation performance. We firstly use a dynamic Gaussian model to describe the nonparametric features of the measurement uncertainty. Then, we propose a likelihood adaptation method that employs the prior information and a belief factor to reduce the measurement noise. The optimal belief factor is attained by deriving the minimum Kullback–Leibler divergence. The likelihood adaptation method can be integrated into any PFs, and we use our method to develop three versions of adaptive PFs for a target tracking system using wireless sensor network. The simulation and experimental results demonstrate that our likelihood adaptation method has greatly improved the estimation performance of PFs in a high noise environment. In addition, the adaptive PFs are highly adaptable to the environment without imposing computational complexity. PMID:27249002

  17. Adaptive Square-Shaped Trajectory-Based Service Location Protocol in Wireless Sensor Networks

    PubMed Central

    Lim, Hwa-Jung; Lee, Joa-Hyoung; Lee, Heon-Guil

    2010-01-01

    In this paper we propose an adaptive square-shaped trajectory (ASST)-based service location method to ensure load scalability in wireless sensor networks. This first establishes a square-shaped trajectory over the nodes that surround a target point computed by the hash function and any user can access it, using the hash. Both the width and the size of the trajectory are dynamically adjustable, depending on the number of queries made to the service information on the trajectory. The number of sensor nodes on the trajectory varies in proportion to the changing trajectory shape, allowing high loads to be distributed around the hot spot area. PMID:22399889

  18. Time series analysis of Adaptive Optics wave-front sensor telemetry data

    SciTech Connect

    Poyneer, L A; Palmer, D

    2004-03-22

    Time series analysis techniques are applied to wave-front sensor telemetry data from the Lick Adaptive Optics System. For 28 fully-illuminated subapertures, telemetry data of 4096 consecutive slope estimates for each subaperture are available. The primary problem is performance comparison of alternative wave-front sensing algorithms. Using direct comparison of data in open loop and closed-loop trials, we analyze algorithm performance in terms of gain, noise and residual power. We also explore the benefits of multi-input Wiener filtering and analyze the open-loop and closed-loop spatial correlations of the sensor measurements.

  19. Adaptive Fault Detection on Liquid Propulsion Systems with Virtual Sensors: Algorithms and Architectures

    NASA Technical Reports Server (NTRS)

    Matthews, Bryan L.; Srivastava, Ashok N.

    2010-01-01

    Prior to the launch of STS-119 NASA had completed a study of an issue in the flow control valve (FCV) in the Main Propulsion System of the Space Shuttle using an adaptive learning method known as Virtual Sensors. Virtual Sensors are a class of algorithms that estimate the value of a time series given other potentially nonlinearly correlated sensor readings. In the case presented here, the Virtual Sensors algorithm is based on an ensemble learning approach and takes sensor readings and control signals as input to estimate the pressure in a subsystem of the Main Propulsion System. Our results indicate that this method can detect faults in the FCV at the time when they occur. We use the standard deviation of the predictions of the ensemble as a measure of uncertainty in the estimate. This uncertainty estimate was crucial to understanding the nature and magnitude of transient characteristics during startup of the engine. This paper overviews the Virtual Sensors algorithm and discusses results on a comprehensive set of Shuttle missions and also discusses the architecture necessary for deploying such algorithms in a real-time, closed-loop system or a human-in-the-loop monitoring system. These results were presented at a Flight Readiness Review of the Space Shuttle in early 2009.

  20. An Adaptive Technique for a Redundant-Sensor Navigation System. Ph.D. Thesis

    NASA Technical Reports Server (NTRS)

    Chien, T. T.

    1972-01-01

    An on-line adaptive technique is developed to provide a self-contained redundant-sensor navigation system with a capability to utilize its full potentiality in reliability and performance. The gyro navigation system is modeled as a Gauss-Markov process, with degradation modes defined as changes in characteristics specified by parameters associated with the model. The adaptive system is formulated as a multistage stochastic process: (1) a detection system, (2) an identification system and (3) a compensation system. It is shown that the sufficient statistics for the partially observable process in the detection and identification system is the posterior measure of the state of degradation, conditioned on the measurement history.

  1. Multipoint dynamically reconfigure adaptive distributed fiber optic acoustic emission sensor (FAESense) system for condition based maintenance

    NASA Astrophysics Data System (ADS)

    Mendoza, Edgar; Prohaska, John; Kempen, Connie; Esterkin, Yan; Sun, Sunjian; Krishnaswamy, Sridhar

    2010-09-01

    This paper describes preliminary results obtained under a Navy SBIR contract by Redondo Optics Inc. (ROI), in collaboration with Northwestern University towards the development and demonstration of a next generation, stand-alone and fully integrated, dynamically reconfigurable, adaptive fiber optic acoustic emission sensor (FAESense™) system for the in-situ unattended detection and localization of shock events, impact damage, cracks, voids, and delaminations in new and aging critical infrastructures found in ships, submarines, aircraft, and in next generation weapon systems. ROI's FAESense™ system is based on the integration of proven state-of-the-art technologies: 1) distributed array of in-line fiber Bragg gratings (FBGs) sensors sensitive to strain, vibration, and acoustic emissions, 2) adaptive spectral demodulation of FBG sensor dynamic signals using two-wave mixing interferometry on photorefractive semiconductors, and 3) integration of all the sensor system passive and active optoelectronic components within a 0.5-cm x 1-cm photonic integrated circuit microchip. The adaptive TWM demodulation methodology allows the measurement of dynamic high frequnency acoustic emission events, while compensating for passive quasi-static strain and temperature drifts. It features a compact, low power, environmentally robust 1-inch x 1-inch x 4-inch small form factor (SFF) package with no moving parts. The FAESense™ interrogation system is microprocessor-controlled using high data rate signal processing electronics for the FBG sensors calibration, temperature compensation and the detection and analysis of acoustic emission signals. Its miniaturized package, low power operation, state-of-the-art data communications, and low cost makes it a very attractive solution for a large number of applications in naval and maritime industries, aerospace, civil structures, the oil and chemical industry, and for homeland security applications.

  2. Improved Testing Capability and Adaptability Through the Use of Wireless Sensors

    NASA Technical Reports Server (NTRS)

    Solano, Wanda M.

    2003-01-01

    From the first Saturn V rocket booster (S-II-T) testing in 1966 and the routine Space Shuttle Main Engine (SSME) testing beginning in 1975, to more recent test programs such as the X-33 Aerospike Engine, the Integrated Powerhead Development (IPD) program, and the Hybrid Sounding Rocket (HYSR), Stennis Space Center (SSC) continues to be a premier location for conducting large-scale testing. Central to each test program is the capability for sensor systems to deliver reliable measurements and high quality data, while also providing a means to monitor the test stand area to the highest degree of safety and sustainability. Sensor wiring is routed along piping and through cable trenches, making its way from the engine test area, through the test stand area and to the signal conditioning building before final transfer to the test control center. When sensor requirements lie outside the reach of the routine sensor cable routing, the use of wireless sensor networks becomes particularly attractive due to their versatility and ease of installation. As part of an on-going effort to enhance the testing capabilities of Stennis Space Center, the Test Technology and Development group has found numerous applications for its sensor-adaptable wireless sensor suite. While not intended for critical engine measurements or control loops, in-house hardware and software development of the sensor suite can provide improved testing capability for a range of applications including the safety monitoring of propellant storage barrels and as an experimental test-bed for embedded health monitoring paradigms.

  3. An Autonomous Self-Aware and Adaptive Fault Tolerant Routing Technique for Wireless Sensor Networks.

    PubMed

    Abba, Sani; Lee, Jeong-A

    2015-01-01

    We propose an autonomous self-aware and adaptive fault-tolerant routing technique (ASAART) for wireless sensor networks. We address the limitations of self-healing routing (SHR) and self-selective routing (SSR) techniques for routing sensor data. We also examine the integration of autonomic self-aware and adaptive fault detection and resiliency techniques for route formation and route repair to provide resilience to errors and failures. We achieved this by using a combined continuous and slotted prioritized transmission back-off delay to obtain local and global network state information, as well as multiple random functions for attaining faster routing convergence and reliable route repair despite transient and permanent node failure rates and efficient adaptation to instantaneous network topology changes. The results of simulations based on a comparison of the ASAART with the SHR and SSR protocols for five different simulated scenarios in the presence of transient and permanent node failure rates exhibit a greater resiliency to errors and failure and better routing performance in terms of the number of successfully delivered network packets, end-to-end delay, delivered MAC layer packets, packet error rate, as well as efficient energy conservation in a highly congested, faulty, and scalable sensor network. PMID:26295236

  4. Integration and bench testing for the GRAVITY Coudé IR adaptive optics (CIAO) wavefront sensor

    NASA Astrophysics Data System (ADS)

    Deen, C.; Yang, P.; Huber, A.; Suarez-Valles, M.; Hippler, S.; Brandner, W.; Gendron, E.; Clénet, Y.; Kendrew, S.; Glauser, A.; Klein, R.; Laun, W.; Lenzen, R.; Neumann, U.; Panduro, J.; Ramos, J.; Rohloff, R.-R.; Salzinger, A.; Zimmerman, N.; Henning, T.; Perraut, K.; Perrin, G.; Straubmeier, C.; Amorim, A.; Eisenhauer, F.

    2014-08-01

    GRAVITY, a second generation instrument for the Very Large Telescope Interferometer (VLTI), will provide an astrometric precision of order 10 micro-arcseconds, an imaging resolution of 4 milli-arcseconds, and low/medium resolution spectro-interferometry. These improvements to the VLTI represent a major upgrade to its current infrared interferometric capabilities, allowing detailed study of obscured environments (e.g. the Galactic Center, young dusty planet-forming disks, dense stellar cores, AGN, etc...). Crucial to the final performance of GRAVITY, the Coudé IR Adaptive Optics (CIAO) system will correct for the effects of the atmosphere at each of the VLT Unit Telescopes. CIAO consists of four new infrared Shack-Hartmann wavefront sensors (WFS) and associated real-time computers/software which will provide infrared wavefront sensing from 1.45-2.45 microns, allowing AO corrections even in regions where optically bright reference sources are scarce. We present here the latest progress on the GRAVITY wavefront sensors. We describe the adaptation and testing of a light-weight version of the ESO Standard Platform for Adaptive optics Real Time Applications (SPARTA-Light) software architecture to the needs of GRAVITY. We also describe the latest integration and test milestones for construction of the initial wave front sensor.

  5. An Autonomous Self-Aware and Adaptive Fault Tolerant Routing Technique for Wireless Sensor Networks

    PubMed Central

    Abba, Sani; Lee, Jeong-A

    2015-01-01

    We propose an autonomous self-aware and adaptive fault-tolerant routing technique (ASAART) for wireless sensor networks. We address the limitations of self-healing routing (SHR) and self-selective routing (SSR) techniques for routing sensor data. We also examine the integration of autonomic self-aware and adaptive fault detection and resiliency techniques for route formation and route repair to provide resilience to errors and failures. We achieved this by using a combined continuous and slotted prioritized transmission back-off delay to obtain local and global network state information, as well as multiple random functions for attaining faster routing convergence and reliable route repair despite transient and permanent node failure rates and efficient adaptation to instantaneous network topology changes. The results of simulations based on a comparison of the ASAART with the SHR and SSR protocols for five different simulated scenarios in the presence of transient and permanent node failure rates exhibit a greater resiliency to errors and failure and better routing performance in terms of the number of successfully delivered network packets, end-to-end delay, delivered MAC layer packets, packet error rate, as well as efficient energy conservation in a highly congested, faulty, and scalable sensor network. PMID:26295236

  6. Sensor selection and chemo-sensory optimization: toward an adaptable chemo-sensory system.

    PubMed

    Vergara, Alexander; Llobet, Eduard

    2011-01-01

    Over the past two decades, despite the tremendous research on chemical sensors and machine olfaction to develop micro-sensory systems that will accomplish the growing existent needs in personal health (implantable sensors), environment monitoring (widely distributed sensor networks), and security/threat detection (chemo/bio warfare agents), simple, low-cost molecular sensing platforms capable of long-term autonomous operation remain beyond the current state-of-the-art of chemical sensing. A fundamental issue within this context is that most of the chemical sensors depend on interactions between the targeted species and the surfaces functionalized with receptors that bind the target species selectively, and that these binding events are coupled with transduction processes that begin to change when they are exposed to the messy world of real samples. With the advent of fundamental breakthroughs at the intersection of materials science, micro- and nano-technology, and signal processing, hybrid chemo-sensory systems have incorporated tunable, optimizable operating parameters, through which changes in the response characteristics can be modeled and compensated as the environmental conditions or application needs change. The objective of this article, in this context, is to bring together the key advances at the device, data processing, and system levels that enable chemo-sensory systems to "adapt" in response to their environments. Accordingly, in this review we will feature the research effort made by selected experts on chemical sensing and information theory, whose work has been devoted to develop strategies that provide tunability and adaptability to single sensor devices or sensory array systems. Particularly, we consider sensor-array selection, modulation of internal sensing parameters, and active sensing. The article ends with some conclusions drawn from the results presented and a visionary look toward the future in terms of how the field may evolve. PMID

  7. An Indirect Adaptive Control Scheme in the Presence of Actuator and Sensor Failures

    NASA Technical Reports Server (NTRS)

    Sun, Joy Z.; Josh, Suresh M.

    2009-01-01

    The problem of controlling a system in the presence of unknown actuator and sensor faults is addressed. The system is assumed to have groups of actuators, and groups of sensors, with each group consisting of multiple redundant similar actuators or sensors. The types of actuator faults considered consist of unknown actuators stuck in unknown positions, as well as reduced actuator effectiveness. The sensor faults considered include unknown biases and outages. The approach employed for fault detection and estimation consists of a bank of Kalman filters based on multiple models, and subsequent control reconfiguration to mitigate the effect of biases caused by failed components as well as to obtain stability and satisfactory performance using the remaining actuators and sensors. Conditions for fault identifiability are presented, and the adaptive scheme is applied to an aircraft flight control example in the presence of actuator failures. Simulation results demonstrate that the method can rapidly and accurately detect faults and estimate the fault values, thus enabling safe operation and acceptable performance in spite of failures.

  8. Urban Fleet Monitoring with GPS and GLONASS

    NASA Astrophysics Data System (ADS)

    Tsakiri, M.; Stewart, M.; Forward, T.; Sandison, D.; Walker, J.

    1998-09-01

    The increasing volume of traffic in urban areas has resulted in steady growth of the mean driving time on fixed routes. Longer driving times lead to significantly higher transportation costs, particularly for vehicle fleets, where efficiency in the distribution of their transport tasks is important in staying competitive in the market. For bus fleets, the optimal control and command of the vehicles is, as well as the economic requirements, a basic function of their general mission. The Global Positioning System (GPS) allows reliable and accurate positioning of public transport vehicles except within the physical limitations imposed by built-up city 'urban canyons'. With a view to the next generation of satellite positioning systems for public transport fleet management, this paper highlights the limitations imposed on current GPS systems operating in the urban canyon. The capabilities of a future positioning system operating in this type of environment are discussed. It is suggested that such a system could comprise receivers capable of integrating the Global Positioning System (GPS) and the Russian equivalent, the Global Navigation Satellite System (GLONASS), and relatively cheap dead-reckoning sensors.

  9. QOS-aware error recovery in wireless body sensor networks using adaptive network coding.

    PubMed

    Razzaque, Mohammad Abdur; Javadi, Saeideh S; Coulibaly, Yahaya; Hira, Muta Tah

    2015-01-01

    Wireless body sensor networks (WBSNs) for healthcare and medical applications are real-time and life-critical infrastructures, which require a strict guarantee of quality of service (QoS), in terms of latency, error rate and reliability. Considering the criticality of healthcare and medical applications, WBSNs need to fulfill users/applications and the corresponding network's QoS requirements. For instance, for a real-time application to support on-time data delivery, a WBSN needs to guarantee a constrained delay at the network level. A network coding-based error recovery mechanism is an emerging mechanism that can be used in these systems to support QoS at very low energy, memory and hardware cost. However, in dynamic network environments and user requirements, the original non-adaptive version of network coding fails to support some of the network and user QoS requirements. This work explores the QoS requirements of WBSNs in both perspectives of QoS. Based on these requirements, this paper proposes an adaptive network coding-based, QoS-aware error recovery mechanism for WBSNs. It utilizes network-level and user-/application-level information to make it adaptive in both contexts. Thus, it provides improved QoS support adaptively in terms of reliability, energy efficiency and delay. Simulation results show the potential of the proposed mechanism in terms of adaptability, reliability, real-time data delivery and network lifetime compared to its counterparts. PMID:25551485

  10. QoS-Aware Error Recovery in Wireless Body Sensor Networks Using Adaptive Network Coding

    PubMed Central

    Razzaque, Mohammad Abdur; Javadi, Saeideh S.; Coulibaly, Yahaya; Hira, Muta Tah

    2015-01-01

    Wireless body sensor networks (WBSNs) for healthcare and medical applications are real-time and life-critical infrastructures, which require a strict guarantee of quality of service (QoS), in terms of latency, error rate and reliability. Considering the criticality of healthcare and medical applications, WBSNs need to fulfill users/applications and the corresponding network's QoS requirements. For instance, for a real-time application to support on-time data delivery, a WBSN needs to guarantee a constrained delay at the network level. A network coding-based error recovery mechanism is an emerging mechanism that can be used in these systems to support QoS at very low energy, memory and hardware cost. However, in dynamic network environments and user requirements, the original non-adaptive version of network coding fails to support some of the network and user QoS requirements. This work explores the QoS requirements of WBSNs in both perspectives of QoS. Based on these requirements, this paper proposes an adaptive network coding-based, QoS-aware error recovery mechanism for WBSNs. It utilizes network-level and user-/application-level information to make it adaptive in both contexts. Thus, it provides improved QoS support adaptively in terms of reliability, energy efficiency and delay. Simulation results show the potential of the proposed mechanism in terms of adaptability, reliability, real-time data delivery and network lifetime compared to its counterparts. PMID:25551485

  11. Adaptive compression of slowly varying images transmitted over Wireless Sensor Networks.

    PubMed

    Nikolakopoulos, George; Kandris, Dionisis; Tzes, Anthony

    2010-01-01

    In this article a scheme for image transmission over Wireless Sensor Networks (WSN) with an adaptive compression factor is introduced. The proposed control architecture affects the quality of the transmitted images according to: (a) the traffic load within the network and (b) the level of details contained in an image frame. Given an approximate transmission period, the adaptive compression mechanism applies Quad Tree Decomposition (QTD) with a varying decomposition compression factor based on a gradient adaptive approach. For the initialization of the proposed control scheme, the desired a priori maximum bound for the transmission time delay is being set, while a tradeoff among the quality of the decomposed image frame and the time needed for completing the transmission of the frame should be taken under consideration. Based on the proposed control mechanism, the quality of the slowly varying transmitted image frames is adaptively deviated based on the measured time delay in the transmission. The efficacy of the adaptive compression control scheme is validated through extended experimental results. PMID:22163598

  12. Sensor Selection and Chemo-Sensory Optimization: Toward an Adaptable Chemo-Sensory System

    PubMed Central

    Vergara, Alexander; Llobet, Eduard

    2011-01-01

    Over the past two decades, despite the tremendous research on chemical sensors and machine olfaction to develop micro-sensory systems that will accomplish the growing existent needs in personal health (implantable sensors), environment monitoring (widely distributed sensor networks), and security/threat detection (chemo/bio warfare agents), simple, low-cost molecular sensing platforms capable of long-term autonomous operation remain beyond the current state-of-the-art of chemical sensing. A fundamental issue within this context is that most of the chemical sensors depend on interactions between the targeted species and the surfaces functionalized with receptors that bind the target species selectively, and that these binding events are coupled with transduction processes that begin to change when they are exposed to the messy world of real samples. With the advent of fundamental breakthroughs at the intersection of materials science, micro- and nano-technology, and signal processing, hybrid chemo-sensory systems have incorporated tunable, optimizable operating parameters, through which changes in the response characteristics can be modeled and compensated as the environmental conditions or application needs change. The objective of this article, in this context, is to bring together the key advances at the device, data processing, and system levels that enable chemo-sensory systems to “adapt” in response to their environments. Accordingly, in this review we will feature the research effort made by selected experts on chemical sensing and information theory, whose work has been devoted to develop strategies that provide tunability and adaptability to single sensor devices or sensory array systems. Particularly, we consider sensor-array selection, modulation of internal sensing parameters, and active sensing. The article ends with some conclusions drawn from the results presented and a visionary look toward the future in terms of how the field may evolve. PMID

  13. Simple broadband implementation of a phase contrast wavefront sensor for adaptive optics

    NASA Technical Reports Server (NTRS)

    Bloemhof, E. E.; Wallace, J. K.

    2004-01-01

    The most critical element of an adaptive optics system is its wavefront sensor, which must measure the closed-loop difference between the corrected wavefront and an ideal template at high speed, in real time, over a dense sampling of the pupil. Most high-order systems have used Shack-Hartmann wavefront sensors, but a novel approach based on Zernike's phase contrast principle appears promising. In this paper we discuss a simple way to achromatize such a phase contrast wavefront sensor, using the pi/2 phase difference between reflected and transmitted rays in a thin, symmetric beam splitter. We further model the response at a range of wavelengths to show that the required transverse dimension of the focal-plane phase-shifting spot, nominally lambda/D, may not be very sensitive to wavelength, and so in practice additional optics to introduce wavelength-dependent transverse magnification achromatizing this spot diameter may not be required. A very simple broadband implementation of the phase contrast wavefront sensor results.

  14. Fleet retrofit report

    NASA Technical Reports Server (NTRS)

    1973-01-01

    Flight tests are evaluated of an avionics system which aids the pilot in making two-segment approaches for noise abatement. The implications are discussed of equipping United's fleet of Boeing 727-200 aircraft with two-segment avionics for use down to Category 2 weather operating minima. The experience is reported of incorporating two-segment approach avionics systems on two different aircraft. The cost of installing dual two-segment approach systems is estimated to be $37,015 per aircraft, including parts, labor, and spares. This is based on the assumption that incremental out-of-service and training costs could be minimized by incorporating the system at airframe overhaul cycle and including training in regular recurrent training. Accelerating the modification schedule could add up to 50 percent to the modification costs. Recurring costs of maintenance of the installation are estimated to be of about the same magnitude as the potential recurrent financial benefits due to fuel savings.

  15. Cask fleet operations study

    SciTech Connect

    Not Available

    1988-01-01

    The Nuclear Waste Policy Act of 1982 assigned to the Department of Energy's (DOE) Office of Civilian Waste Management the responsibility for disposing of high-level waste and spent fuel. A significant part of that responsibility involves transporting nuclear waste materials within the federal waste management system; that is, from the waste generator to the repository. The lead responsibility for transportation operations has been assigned to Oak Ridge Operations, with Oak Ridge National Laboratory (ORNL) providing technical support through the Transportation Operations Support Task Group. One of the ORNL support activities involves assessing what facilities, equipment and services are required to assure that an acceptable, cost-effective and safe transportation operations system can be designed, operated and maintained. This study reviews, surveys and assesses the experience of Nuclear Assurance Corporation (NAC) in operating a fleet of spent-fuel shipping casks to aid in developing the spent-fuel transportation system.

  16. Adaptive UAV Attitude Estimation Employing Unscented Kalman Filter, FOAM and Low-Cost MEMS Sensors

    PubMed Central

    de Marina, Héctor García; Espinosa, Felipe; Santos, Carlos

    2012-01-01

    Navigation employing low cost MicroElectroMechanical Systems (MEMS) sensors in Unmanned Aerial Vehicles (UAVs) is an uprising challenge. One important part of this navigation is the right estimation of the attitude angles. Most of the existent algorithms handle the sensor readings in a fixed way, leading to large errors in different mission stages like take-off aerobatic maneuvers. This paper presents an adaptive method to estimate these angles using off-the-shelf components. This paper introduces an Attitude Heading Reference System (AHRS) based on the Unscented Kalman Filter (UKF) using the Fast Optimal Attitude Matrix (FOAM) algorithm as the observation model. The performance of the method is assessed through simulations. Moreover, field experiments are presented using a real fixed-wing UAV. The proposed low cost solution, implemented in a microcontroller, shows a satisfactory real time performance. PMID:23012559

  17. Adaptive UAV attitude estimation employing unscented Kalman Filter, FOAM and low-cost MEMS sensors.

    PubMed

    de Marina, Héctor García; Espinosa, Felipe; Santos, Carlos

    2012-01-01

    Navigation employing low cost MicroElectroMechanical Systems (MEMS) sensors in Unmanned Aerial Vehicles (UAVs) is an uprising challenge. One important part of this navigation is the right estimation of the attitude angles. Most of the existent algorithms handle the sensor readings in a fixed way, leading to large errors in different mission stages like take-off aerobatic maneuvers. This paper presents an adaptive method to estimate these angles using off-the-shelf components. This paper introduces an Attitude Heading Reference System (AHRS) based on the Unscented Kalman Filter (UKF) using the Fast Optimal Attitude Matrix (FOAM) algorithm as the observation model. The performance of the method is assessed through simulations. Moreover, field experiments are presented using a real fixed-wing UAV. The proposed low cost solution, implemented in a microcontroller, shows a satisfactory real time performance. PMID:23012559

  18. Code division controlled-MAC in wireless sensor network by adaptive binary signature design

    NASA Astrophysics Data System (ADS)

    Wei, Lili; Batalama, Stella N.; Pados, Dimitris A.; Suter, Bruce

    2007-04-01

    We consider the problem of signature waveform design for code division medium-access-control (MAC) of wireless sensor networks (WSN). In contract to conventional randomly chosen orthogonal codes, an adaptive signature design strategy is developed under the maximum pre-detection SINR (signal to interference plus noise ratio) criterion. The proposed algorithm utilizes slowest descent cords of the optimization surface to move toward the optimum solution and exhibits, upon eigenvector decomposition, linear computational complexity with respect to signature length. Numerical and simulation studies demonstrate the performance of the proposed method and offer comparisons with conventional signature code sets.

  19. A hybrid adaptive routing algorithm for event-driven wireless sensor networks.

    PubMed

    Figueiredo, Carlos M S; Nakamura, Eduardo F; Loureiro, Antonio A F

    2009-01-01

    Routing is a basic function in wireless sensor networks (WSNs). For these networks, routing algorithms depend on the characteristics of the applications and, consequently, there is no self-contained algorithm suitable for every case. In some scenarios, the network behavior (traffic load) may vary a lot, such as an event-driven application, favoring different algorithms at different instants. This work presents a hybrid and adaptive algorithm for routing in WSNs, called Multi-MAF, that adapts its behavior autonomously in response to the variation of network conditions. In particular, the proposed algorithm applies both reactive and proactive strategies for routing infrastructure creation, and uses an event-detection estimation model to change between the strategies and save energy. To show the advantages of the proposed approach, it is evaluated through simulations. Comparisons with independent reactive and proactive algorithms show improvements on energy consumption. PMID:22423207

  20. Performance simulation of the ERIS pyramid wavefront sensor module in the VLT adaptive optics facility

    NASA Astrophysics Data System (ADS)

    Quirós-Pacheco, Fernando; Agapito, Guido; Riccardi, Armando; Esposito, Simone; Le Louarn, Miska; Marchetti, Enrico

    2012-07-01

    This paper presents the performance analysis based on numerical simulations of the Pyramid Wavefront sensor Module (PWM) to be included in ERIS, the new Adaptive Optics (AO) instrument for the Adaptive Optics Facility (AOF). We have analyzed the performance of the PWM working either in a low-order or in a high-order wavefront sensing mode of operation. We show that the PWM in the high-order sensing mode can provide SR > 90% in K band using bright guide stars under median seeing conditions (0.85 arcsec seeing and 15 m/s of wind speed). In the low-order sensing mode, the PWM can sense and correct Tip-Tilt (and if requested also Focus mode) with the precision required to assist the LGS observations to get an SR > 60% and > 20% in K band, using up to a ~16.5 and ~19.5 R-magnitude guide star, respectively.

  1. LPTA: Location Predictive and Time Adaptive Data Gathering Scheme with Mobile Sink for Wireless Sensor Networks

    PubMed Central

    Rodrigues, Joel J. P. C.

    2014-01-01

    This paper exploits sink mobility to prolong the lifetime of sensor networks while maintaining the data transmission delay relatively low. A location predictive and time adaptive data gathering scheme is proposed. In this paper, we introduce a sink location prediction principle based on loose time synchronization and deduce the time-location formulas of the mobile sink. According to local clocks and the time-location formulas of the mobile sink, nodes in the network are able to calculate the current location of the mobile sink accurately and route data packets timely toward the mobile sink by multihop relay. Considering that data packets generating from different areas may be different greatly, an adaptive dwelling time adjustment method is also proposed to balance energy consumption among nodes in the network. Simulation results show that our data gathering scheme enables data routing with less data transmission time delay and balance energy consumption among nodes. PMID:25302327

  2. Coupled sensor/platform control design for low-level chemical detection with position-adaptive micro-UAVs

    NASA Astrophysics Data System (ADS)

    Goodwin, Thomas; Carr, Ryan; Mitra, Atindra K.; Selmic, Rastko R.

    2009-05-01

    We discuss the development of Position-Adaptive Sensors [1] for purposes for detecting embedded chemical substances in challenging environments. This concept is a generalization of patented Position-Adaptive Radar Concepts developed at AFRL for challenging conditions such as urban environments. For purposes of investigating the detection of chemical substances using multiple MAV (Micro-UAV) platforms, we have designed and implemented an experimental testbed with sample structures such as wooden carts that contain controlled leakage points. Under this general concept, some of the members of a MAV swarm can serve as external position-adaptive "transmitters" by blowing air over the cart and some of the members of a MAV swarm can serve as external position-adaptive "receivers" that are equipped with chemical or biological (chem/bio) sensors that function as "electronic noses". The objective can be defined as improving the particle count of chem/bio concentrations that impinge on a MAV-based position-adaptive sensor that surrounds a chemical repository, such as a cart, via the development of intelligent position-adaptive control algorithms. The overall effect is to improve the detection and false-alarm statistics of the overall system. Within the major sections of this paper, we discuss a number of different aspects of developing our initial MAV-Based Sensor Testbed. This testbed includes blowers to simulate position-adaptive excitations and a MAV from Draganfly Innovations Inc. with stable design modifications to accommodate our chem/bio sensor boom design. We include details with respect to several critical phases of the development effort including development of the wireless sensor network and experimental apparatus, development of the stable sensor boom for the MAV, integration of chem/bio sensors and sensor node onto the MAV and boom, development of position-adaptive control algorithms and initial tests at IDCAST (Institute for the Development and

  3. Adaptive-Compression Based Congestion Control Technique for Wireless Sensor Networks

    PubMed Central

    Lee, Joa-Hyoung; Jung, In-Bum

    2010-01-01

    Congestion in a wireless sensor network causes an increase in the amount of data loss and delays in data transmission. In this paper, we propose a new congestion control technique (ACT, Adaptive Compression-based congestion control Technique) based on an adaptive compression scheme for packet reduction in case of congestion. The compression techniques used in the ACT are Discrete Wavelet Transform (DWT), Adaptive Differential Pulse Code Modulation (ADPCM), and Run-Length Coding (RLC). The ACT first transforms the data from the time domain to the frequency domain, reduces the range of data by using ADPCM, and then reduces the number of packets with the help of RLC before transferring the data to the source node. It introduces the DWT for priority-based congestion control because the DWT classifies the data into four groups with different frequencies. The ACT assigns priorities to these data groups in an inverse proportion to the respective frequencies of the data groups and defines the quantization step size of ADPCM in an inverse proportion to the priorities. RLC generates a smaller number of packets for a data group with a low priority. In the relaying node, the ACT reduces the amount of packets by increasing the quantization step size of ADPCM in case of congestion. Moreover, in order to facilitate the back pressure, the queue is controlled adaptively according to the congestion state. We experimentally demonstrate that the ACT increases the network efficiency and guarantees fairness to sensor nodes, as compared with the existing methods. Moreover, it exhibits a very high ratio of the available data in the sink. PMID:22319280

  4. A distance-aware replica adaptive data gathering protocol for Delay Tolerant Mobile Sensor Networks.

    PubMed

    Feng, Yong; Gong, Haigang; Fan, Mingyu; Liu, Ming; Wang, Xiaomin

    2011-01-01

    In Delay Tolerant Mobile Sensor Networks (DTMSNs) that have the inherent features of intermitted connectivity and frequently changing network topology it is reasonable to utilize multi-replica schemes to improve the data gathering performance. However, most existing multi-replica approaches inject a large amount of message copies into the network to increase the probability of message delivery, which may drain each mobile node's limited battery supply faster and result in too much contention for the restricted resources of the DTMSN, so a proper data gathering scheme needs a trade off between the number of replica messages and network performance. In this paper, we propose a new data gathering protocol called DRADG (for Distance-aware Replica Adaptive Data Gathering protocol), which economizes network resource consumption through making use of a self-adapting algorithm to cut down the number of redundant replicas of messages, and achieves a good network performance by leveraging the delivery probabilities of the mobile sensors as main routing metrics. Simulation results have shown that the proposed DRADG protocol achieves comparable or higher message delivery ratios at the cost of the much lower transmission overhead than several current DTMSN data gathering schemes. PMID:22163839

  5. Shack-Hartmann wavefront sensor with large dynamic range by adaptive spot search method.

    PubMed

    Shinto, Hironobu; Saita, Yusuke; Nomura, Takanori

    2016-07-10

    A Shack-Hartmann wavefront sensor (SHWFS) that consists of a microlens array and an image sensor has been used to measure the wavefront aberrations of human eyes. However, a conventional SHWFS has finite dynamic range depending on the diameter of the each microlens. The dynamic range cannot be easily expanded without a decrease of the spatial resolution. In this study, an adaptive spot search method to expand the dynamic range of an SHWFS is proposed. In the proposed method, spots are searched with the help of their approximate displacements measured with low spatial resolution and large dynamic range. By the proposed method, a wavefront can be correctly measured even if the spot is beyond the detection area. The adaptive spot search method is realized by using the special microlens array that generates both spots and discriminable patterns. The proposed method enables expanding the dynamic range of an SHWFS with a single shot and short processing time. The performance of the proposed method is compared with that of a conventional SHWFS by optical experiments. Furthermore, the dynamic range of the proposed method is quantitatively evaluated by numerical simulations. PMID:27409319

  6. Efficient integration of spectral features for vehicle tracking utilizing an adaptive sensor

    NASA Astrophysics Data System (ADS)

    Uzkent, Burak; Hoffman, Matthew J.; Vodacek, Anthony

    2015-03-01

    Object tracking in urban environments is an important and challenging problem that is traditionally tackled using visible and near infrared wavelengths. By inserting extended data such as spectral features of the objects one can improve the reliability of the identification process. However, huge increase in data created by hyperspectral imaging is usually prohibitive. To overcome the complexity problem, we propose a persistent air-to-ground target tracking system inspired by a state-of-the-art, adaptive, multi-modal sensor. The adaptive sensor is capable of providing panchromatic images as well as the spectra of desired pixels. This addresses the data challenge of hyperspectral tracking by only recording spectral data as needed. Spectral likelihoods are integrated into a data association algorithm in a Bayesian fashion to minimize the likelihood of misidentification. A framework for controlling spectral data collection is developed by incorporating motion segmentation information and prior information from a Gaussian Sum filter (GSF) movement predictions from a multi-model forecasting set. An intersection mask of the surveillance area is extracted from OpenStreetMap source and incorporated into the tracking algorithm to perform online refinement of multiple model set. The proposed system is tested using challenging and realistic scenarios generated in an adverse environment.

  7. Fleet DNA Project (Fact Sheet)

    SciTech Connect

    Not Available

    2012-10-01

    The Fleet DNA Project - designed by the U.S. Department of Energy's National Renewable Energy Laboratory (NREL) in partnership with Oak Ridge National Laboratory - aims to accelerate the evolution of advanced vehicle development and support the strategic deployment of market-ready technologies that reduce costs, fuel consumption, and emissions. At the heart of the Fleet DNA Project is a clearinghouse of medium- and heavy-duty commercial fleet transportation data for optimizing the design of advanced vehicle technologies or for selecting a given technology to invest in. An easy-to-access online database will help vehicle manufacturers and fleets understand the broad operational range for many of today's commercial vehicle vocations.

  8. Adaptive Routing Protocol with Energy Efficiency and Event Clustering for Wireless Sensor Networks

    NASA Astrophysics Data System (ADS)

    Tran Quang, Vinh; Miyoshi, Takumi

    Wireless sensor network (WSN) is a promising approach for a variety of applications. Routing protocol for WSNs is very challenging because it should be simple, scalable, energy-efficient, and robust to deal with a very large number of nodes, and also self-configurable to node failures and changes of the network topology dynamically. Recently, many researchers have focused on developing hierarchical protocols for WSNs. However, most protocols in the literatures cannot scale well to large sensor networks and difficult to apply in the real applications. In this paper, we propose a novel adaptive routing protocol for WSNs called ARPEES. The main design features of the proposed method are: energy efficiency, dynamic event clustering, and multi-hop relay considering the trade-off relationship between the residual energy available of relay nodes and distance from the relay node to the base station. With a distributed and light overhead traffic approach, we spread energy consumption required for aggregating data and relaying them to different sensor nodes to prolong the lifetime of the whole network. In this method, we consider energy and distance as the parameters in the proposed function to select relay nodes and finally select the optimal path among cluster heads, relay nodes and the base station. The simulation results show that our routing protocol achieves better performance than other previous routing protocols.

  9. Recognition of human emotion using sensor agent robot for interactive and adaptive living spaces

    NASA Astrophysics Data System (ADS)

    Murata, Sozo; Mita, Akira

    2011-04-01

    Safer, more comfortable and energy-efficient living spaces are always demanded. However, most buildings are designed based on prescribed scenarios so that they do not act on abrupt changes of environments. We propose "Biofication of Living Spaces" that has functions of learning occupants' lifestyles and taking actions based on collected information. By doing so, we can incorporate the high adaptability to the building. Our goal is to make living spaces more "comfortable". However, human beings have emotion that implies the meaning of "comfortable" depends on each individual. Therefore our study focuses on recognition of human emotion. We suggest using robots as sensor agents. By using robots equipped with various sensors, they can interact with occupants and environment. We use a sensor agent robot called "e-bio". In this research, we construct a human tracking system and identified emotions of residents using their walking information. We focus on the influences of illuminance and sound. We classified emotions by calculating the distance of the mapped points in comfortable and uncomfortable spaces with parametric eigen space method, in which parameters are determined by a mapping of tracks in the space. As a method of pattern recognition, a weighted k-nearest neighbor is used. Experiments considering illuminance and sound environments, illustrates good correlation between emotion and environments.

  10. An Adaptive Sampling System for Sensor Nodes in Body Area Networks.

    PubMed

    Rieger, R; Taylor, J

    2014-04-23

    The importance of body sensor networks to monitor patients over a prolonged period of time has increased with an advance in home healthcare applications. Sensor nodes need to operate with very low-power consumption and under the constraint of limited memory capacity. Therefore, it is wasteful to digitize the sensor signal at a constant sample rate, given that the frequency contents of the signals vary with time. Adaptive sampling is established as a practical method to reduce the sample data volume. In this paper a low-power analog system is proposed, which adjusts the converter clock rate to perform a peak-picking algorithm on the second derivative of the input signal. The presented implementation does not require an analog-to-digital converter or a digital processor in the sample selection process. The criteria for selecting a suitable detection threshold are discussed, so that the maximum sampling error can be limited. A circuit level implementation is presented. Measured results exhibit a significant reduction in the average sample frequency and data rate of over 50% and 38% respectively. PMID:24760918

  11. Adaptive two-wave mixing wavelength demodulation of fiber Bragg grating sensor for monitoring dynamic strains

    NASA Astrophysics Data System (ADS)

    Qiao, Yi; Zhou, Yi; Krishnaswamy, Sridhar

    2005-05-01

    A two-wave mixing (TWM) wavelength demodulator using InP:Fe photorefractive crystal (PRC) in the C-band (1530-1570nm) is demonstrated. The system can be used as a wavelength demodulator for use with Fiber Bragg Grating (FBG) sensors to monitor dynamic strains. In this configuration, the FBG is illuminated with a broadband source, and any strain in the FBG is encoded as a wavelength shift of the light reflected by the FBG. The reflected light from the FBG is spilt into two unbalanced paths and both beams (pump and signal) mix in the PRC. Any wavelength shift of the reflected light results in an equivalent phase shift between the pump and signal beams as they travel unbalanced path lengths. Since TWM is an adaptive process, the two interfering beams are naturally in quadrature and remain in quadrature even in the presence of large quasi-static strains. We demonstrate that FBG demodulation using TWM has the ability to selectively monitor dynamic strains without the need for active compensation of large quasi-static strains that otherwise would cause the FBG sensor to drift. As TWM interferometers can be readily multiplexed at relatively low cost; the proposed technique can be used to demodulate signals from a network of FBG sensors for use in structural health monitoring.

  12. Optical Communication System for Remote Monitoring and Adaptive Control of Distributed Ground Sensors Exhibiting Collective Intelligence

    SciTech Connect

    Cameron, S.M.; Stantz, K.M.; Trahan, M.W.; Wagner, J.S.

    1998-11-01

    Comprehensive management of the battle-space has created new requirements in information management, communication, and interoperability as they effect surveillance and situational awareness. The objective of this proposal is to expand intelligent controls theory to produce a uniquely powerful implementation of distributed ground-based measurement incorporating both local collective behavior, and interoperative global optimization for sensor fusion and mission oversight. By using a layered hierarchal control architecture to orchestrate adaptive reconfiguration of autonomous robotic agents, we can improve overall robustness and functionality in dynamic tactical environments without information bottlenecks. In this concept, each sensor is equipped with a miniaturized optical reflectance modulator which is interactively monitored as a remote transponder using a covert laser communication protocol from a remote mothership or operative. Robot data-sharing at the ground level can be leveraged with global evaluation criteria, including terrain overlays and remote imaging data. Information sharing and distributed intelli- gence opens up a new class of remote-sensing applications in which small single-function autono- mous observers at the local level can collectively optimize and measure large scale ground-level signals. AS the need for coverage and the number of agents grows to improve spatial resolution, cooperative behavior orchestrated by a global situational awareness umbrella will be an essential ingredient to offset increasing bandwidth requirements within the net. A system of the type described in this proposal will be capable of sensitively detecting, tracking, and mapping spatial distributions of measurement signatures which are non-stationary or obscured by clutter and inter- fering obstacles by virtue of adaptive reconfiguration. This methodology could be used, for example, to field an adaptive ground-penetrating radar for detection of underground structures in

  13. Adaptive Sensor Optimization and Cognitive Image Processing Using Autonomous Optical Neuroprocessors

    SciTech Connect

    CAMERON, STEWART M.

    2001-10-01

    Measurement and signal intelligence demands has created new requirements for information management and interoperability as they affect surveillance and situational awareness. Integration of on-board autonomous learning and adaptive control structures within a remote sensing platform architecture would substantially improve the utility of intelligence collection by facilitating real-time optimization of measurement parameters for variable field conditions. A problem faced by conventional digital implementations of intelligent systems is the conflict between a distributed parallel structure on a sequential serial interface functionally degrading bandwidth and response time. In contrast, optically designed networks exhibit the massive parallelism and interconnect density needed to perform complex cognitive functions within a dynamic asynchronous environment. Recently, all-optical self-organizing neural networks exhibiting emergent collective behavior which mimic perception, recognition, association, and contemplative learning have been realized using photorefractive holography in combination with sensory systems for feature maps, threshold decomposition, image enhancement, and nonlinear matched filters. Such hybrid information processors depart from the classical computational paradigm based on analytic rules-based algorithms and instead utilize unsupervised generalization and perceptron-like exploratory or improvisational behaviors to evolve toward optimized solutions. These systems are robust to instrumental systematics or corrupting noise and can enrich knowledge structures by allowing competition between multiple hypotheses. This property enables them to rapidly adapt or self-compensate for dynamic or imprecise conditions which would be unstable using conventional linear control models. By incorporating an intelligent optical neuroprocessor in the back plane of an imaging sensor, a broad class of high-level cognitive image analysis problems including geometric

  14. Preliminary tests of a possible outdoor light adaptation solution for a fly inspired visual sensor: a biomimetic solution - biomed 2011.

    PubMed

    Dean, Brian K; Wright, Cameron H G; Barrett, Steven F

    2011-01-01

    Two previous papers, presented at RMBS in 2009 and 2010, introduced a fly inspired vision sensor that could adapt to indoor light conditions by mimicking the light adaptation process of the commonhousefly, Muscadomestica. A new system has been designed that should allow the sensor to adapt to outdoor light conditions which will enable the sensor’s use inapplications such as: unmanned aerial vehicle (UAV) obstacle avoidance, UAV landing support, target tracking, wheelchair guidance, large structure monitoring, and many other outdoor applications. A sensor of this type is especially suited for these applications due to features of hyperacuity (or an ability to achieve movement resolution beyond the theoretical limit), extreme sensitivity to motion, and (through software simulation) image edge extraction, motion detection, and orientation and location of a line.Many of these qualities are beyond the ability of traditional computervision sensors such as charge coupled device (CCD) arrays.To achieve outdoor light adaptation, a variety of design obstacles have to be overcome such as infrared interference, dynamic range expansion, and light saturation. The newly designed system overcomes the latter two design obstacles by mimicking the fly’s solution of logarithmic compression followed by removal of the average background light intensity. This paper presents the new design and the preliminary tests that were conducted to determine its effectiveness. PMID:21525612

  15. A uniquely adaptable pore is consistent with NALCN being an ion sensor

    PubMed Central

    Senatore, Adriano; Spafford, J. David

    2013-01-01

    NALCN is an intriguing, orphan ion channel among the 4x6TM family of related voltage-gated cation channels, sharing a common architecture of four homologous domains consisting of six transmembrane helices, separated by three cytoplasmic linkers and delimited by N and C-terminal ends. NALCN is one of the shortest 4x6TM family members, lacking much of the variation that provides the diverse palate of gating features, and tissue specific adaptations of sodium and calcium channels. NALCN’s most distinctive feature is that that it possesses a highly adaptable pore with a calcium-like EEEE selectivity filter in radially symmetrical animals and a more sodium-like EEKE or EKEE selectivity filter in bilaterally symmetrical animals including vertebrates. Two lineages of animals evolved alternative calcium-like EEEE and sodium-like EEKE / EKEE pores, spliced to regulate NALCN functions in differing cellular environments, such as muscle (heart and skeletal) and secretory tissue (brain and glands), respectively. A highly adaptable pore in an otherwise conserved ion channel in the 4x6TM channel family is not consistent with a role for NALCN in directly gating a significant ion conductance that can be either sodium ions or calcium ions. NALCN was proposed to be an expressible Gd3+-sensitive, NMDG+-impermeant, non-selective and ohmic leak conductance in HEK-293T cells, but we were unable to distinguish these reported currents from leaky patch currents (ILP) in control HEK-293T cells. We suggest that NALCN functions as a sensor for the much larger UNC80/UNC79 complex, in a manner consistent with the coupling mechanism known for other weakly or non-conducting 4x6TM channel sensor proteins such as Nax or Cav1.1. We propose that NALCN serves as a variable sensor that responds to calcium or sodium ion flux, depending on whether the total cellular current density is generated more from calcium-selective or sodium-selective channels. PMID:23442378

  16. Multimode delta-E effect magnetic field sensors with adapted electrodes

    NASA Astrophysics Data System (ADS)

    Zabel, Sebastian; Reermann, Jens; Fichtner, Simon; Kirchhof, Christine; Quandt, Eckhard; Wagner, Bernhard; Schmidt, Gerhard; Faupel, Franz

    2016-05-01

    We present an analytical and experimental study on low-noise piezoelectric thin film resonators that utilize the delta-E effect of a magnetostrictive layer to measure magnetic fields at low frequencies. Calculations from a physical model of the electromechanical resonator enable electrode designs to efficiently operate in the first and second transversal bending modes. As predicted by our calculations, the adapted electrode design improves the sensitivity by a factor of 6 and reduces the dynamic range of the sensor output by 16 dB, which significantly eases the requirements on readout electronics. Magnetic measurements show a bandwidth of 100 Hz at a noise level of about 100 pTHz-0.5.

  17. Experience with wavefront sensor and deformable mirror interfaces for wide-field adaptive optics systems

    NASA Astrophysics Data System (ADS)

    Basden, A. G.; Atkinson, D.; Bharmal, N. A.; Bitenc, U.; Brangier, M.; Buey, T.; Butterley, T.; Cano, D.; Chemla, F.; Clark, P.; Cohen, M.; Conan, J.-M.; de Cos, F. J.; Dickson, C.; Dipper, N. A.; Dunlop, C. N.; Feautrier, P.; Fusco, T.; Gach, J. L.; Gendron, E.; Geng, D.; Goodsell, S. J.; Gratadour, D.; Greenaway, A. H.; Guesalaga, A.; Guzman, C. D.; Henry, D.; Holck, D.; Hubert, Z.; Huet, J. M.; Kellerer, A.; Kulcsar, C.; Laporte, P.; Le Roux, B.; Looker, N.; Longmore, A. J.; Marteaud, M.; Martin, O.; Meimon, S.; Morel, C.; Morris, T. J.; Myers, R. M.; Osborn, J.; Perret, D.; Petit, C.; Raynaud, H.; Reeves, A. P.; Rousset, G.; Sanchez Lasheras, F.; Sanchez Rodriguez, M.; Santos, J. D.; Sevin, A.; Sivo, G.; Stadler, E.; Stobie, B.; Talbot, G.; Todd, S.; Vidal, F.; Younger, E. J.

    2016-06-01

    Recent advances in adaptive optics (AO) have led to the implementation of wide field-of-view AO systems. A number of wide-field AO systems are also planned for the forthcoming Extremely Large Telescopes. Such systems have multiple wavefront sensors of different types, and usually multiple deformable mirrors (DMs). Here, we report on our experience integrating cameras and DMs with the real-time control systems of two wide-field AO systems. These are CANARY, which has been operating on-sky since 2010, and DRAGON, which is a laboratory AO real-time demonstrator instrument. We detail the issues and difficulties that arose, along with the solutions we developed. We also provide recommendations for consideration when developing future wide-field AO systems.

  18. Load-Adaptive Practical Multi-Channel Communications in Wireless Sensor Networks

    PubMed Central

    Islam, Md. Shariful; Alam, Muhammad Mahbub; Hong, Choong Seon; Lee, Sungwon

    2010-01-01

    In recent years, a significant number of sensor node prototypes have been designed that provide communications in multiple channels. This multi-channel feature can be effectively exploited to increase the overall capacity and performance of wireless sensor networks (WSNs). In this paper, we present a multi-channel communications system for WSNs that is referred to as load-adaptive practical multi-channel communications (LPMC). LPMC estimates the active load of a channel at the sink since it has a more comprehensive view of the network behavior, and dynamically adds or removes channels based on the estimated load. LPMC updates the routing path to balance the loads of the channels. The nodes in a path use the same channel; therefore, they do not need to switch channels to receive or forward packets. LPMC has been evaluated through extensive simulations, and the results demonstrate that it can effectively increase the delivery ratio, network throughput, and channel utilization, and that it can decrease the end-to-end delay and energy consumption. PMID:22163685

  19. Load-adaptive practical multi-channel communications in wireless sensor networks.

    PubMed

    Islam, Md Shariful; Alam, Muhammad Mahbub; Hong, Choong Seon; Lee, Sungwon

    2010-01-01

    In recent years, a significant number of sensor node prototypes have been designed that provide communications in multiple channels. This multi-channel feature can be effectively exploited to increase the overall capacity and performance of wireless sensor networks (WSNs). In this paper, we present a multi-channel communications system for WSNs that is referred to as load-adaptive practical multi-channel communications (LPMC). LPMC estimates the active load of a channel at the sink since it has a more comprehensive view of the network behavior, and dynamically adds or removes channels based on the estimated load. LPMC updates the routing path to balance the loads of the channels. The nodes in a path use the same channel; therefore, they do not need to switch channels to receive or forward packets. LPMC has been evaluated through extensive simulations, and the results demonstrate that it can effectively increase the delivery ratio, network throughput, and channel utilization, and that it can decrease the end-to-end delay and energy consumption. PMID:22163685

  20. Adaptive multi-sensor biomimetics for unsupervised submarine hunt (AMBUSH): Early results

    NASA Astrophysics Data System (ADS)

    Blouin, Stéphane

    2014-10-01

    Underwater surveillance is inherently difficult because acoustic wave propagation and transmission are limited and unpredictable when targets and sensors move around in the communication-opaque undersea environment. Today's Navy underwater sensors enable the collection of a massive amount of data, often analyzed offtine. The Navy of tomorrow will dominate by making sense of that data in real-time. DRDC's AMBUSH project proposes a new undersea-surveillance network paradigm that will enable such a real-time operation. Nature abounds with examples of collaborative tasks taking place despite limited communication and computational capabilities. This publication describes a year's worth of research efforts finding inspiration in Nature's collaborative tasks such as wolves hunting in packs. This project proposes the utilization of a heterogeneous network combining both static and mobile network nodes. The military objective is to enable an unsupervised surveillance capability while maximizing target localization performance and endurance. The scientific objective is to develop the necessary technology to acoustically and passively localize a noise-source of interest in shallow waters. The project fulfills these objectives via distributed computing and adaptation to changing undersea conditions. Specific research interests discussed here relate to approaches for performing: (a) network self-discovery, (b) network connectivity self-assessment, (c) opportunistic network routing, (d) distributed data-aggregation, and (e) simulation of underwater acoustic propagation. We present early results then followed by a discussion about future work.

  1. RheoStim: Development of an Adaptive Multi-Sensor to Prevent Venous Stasis.

    PubMed

    Weyer, Sören; Weishaupt, Fabio; Kleeberg, Christian; Leonhardt, Steffen; Teichmann, Daniel

    2016-01-01

    Chronic venous insufficiency of the lower limbs is often underestimated and, in the absence of therapy, results in increasingly severe complications, including therapy-resistant tissue defects. Therefore, early diagnosis and adequate therapy is of particular importance. External counter pulsation (ECP) therapy is a method used to assist the venous system. The main principle of ECP is to squeeze the inner leg vessels by muscle contractions, which are evoked by functional electrical stimulation. A new adaptive trigger method is proposed, which improves and supplements the current therapeutic options by means of pulse synchronous electro-stimulation of the muscle pump. For this purpose, blood flow is determined by multi-sensor plethysmography. The hardware design and signal processing of this novel multi-sensor plethysmography device are introduced. The merged signal is used to determine the phase of the cardiac cycle, to ensure stimulation of the muscle pump during the filling phase of the heart. The pulse detection of the system is validated against a gold standard and provides a sensitivity of 98% and a false-negative rate of 2% after physical exertion. Furthermore, flow enhancement of the system has been validated by duplex ultrasonography. The results show a highly increased blood flow in the popliteal vein at the knee. PMID:27023544

  2. An Efficient and Adaptive Mutual Authentication Framework for Heterogeneous Wireless Sensor Network-Based Applications

    PubMed Central

    Kumar, Pardeep; Ylianttila, Mika; Gurtov, Andrei; Lee, Sang-Gon; Lee, Hoon-Jae

    2014-01-01

    Robust security is highly coveted in real wireless sensor network (WSN) applications since wireless sensors' sense critical data from the application environment. This article presents an efficient and adaptive mutual authentication framework that suits real heterogeneous WSN-based applications (such as smart homes, industrial environments, smart grids, and healthcare monitoring). The proposed framework offers: (i) key initialization; (ii) secure network (cluster) formation (i.e., mutual authentication and dynamic key establishment); (iii) key revocation; and (iv) new node addition into the network. The correctness of the proposed scheme is formally verified. An extensive analysis shows the proposed scheme coupled with message confidentiality, mutual authentication and dynamic session key establishment, node privacy, and message freshness. Moreover, the preliminary study also reveals the proposed framework is secure against popular types of attacks, such as impersonation attacks, man-in-the-middle attacks, replay attacks, and information-leakage attacks. As a result, we believe the proposed framework achieves efficiency at reasonable computation and communication costs and it can be a safeguard to real heterogeneous WSN applications. PMID:24521942

  3. An efficient and adaptive mutual authentication framework for heterogeneous wireless sensor network-based applications.

    PubMed

    Kumar, Pardeep; Ylianttila, Mika; Gurtov, Andrei; Lee, Sang-Gon; Lee, Hoon-Jae

    2014-01-01

    Robust security is highly coveted in real wireless sensor network (WSN) applications since wireless sensors' sense critical data from the application environment. This article presents an efficient and adaptive mutual authentication framework that suits real heterogeneous WSN-based applications (such as smart homes, industrial environments, smart grids, and healthcare monitoring). The proposed framework offers: (i) key initialization; (ii) secure network (cluster) formation (i.e., mutual authentication and dynamic key establishment); (iii) key revocation; and (iv) new node addition into the network. The correctness of the proposed scheme is formally verified. An extensive analysis shows the proposed scheme coupled with message confidentiality, mutual authentication and dynamic session key establishment, node privacy, and message freshness. Moreover, the preliminary study also reveals the proposed framework is secure against popular types of attacks, such as impersonation attacks, man-in-the-middle attacks, replay attacks, and information-leakage attacks. As a result, we believe the proposed framework achieves efficiency at reasonable computation and communication costs and it can be a safeguard to real heterogeneous WSN applications. PMID:24521942

  4. Design and analysis of self-adapted task scheduling strategies in wireless sensor networks.

    PubMed

    Guo, Wenzhong; Xiong, Naixue; Chao, Han-Chieh; Hussain, Sajid; Chen, Guolong

    2011-01-01

    In a wireless sensor network (WSN), the usage of resources is usually highly related to the execution of tasks which consume a certain amount of computing and communication bandwidth. Parallel processing among sensors is a promising solution to provide the demanded computation capacity in WSNs. Task allocation and scheduling is a typical problem in the area of high performance computing. Although task allocation and scheduling in wired processor networks has been well studied in the past, their counterparts for WSNs remain largely unexplored. Existing traditional high performance computing solutions cannot be directly implemented in WSNs due to the limitations of WSNs such as limited resource availability and the shared communication medium. In this paper, a self-adapted task scheduling strategy for WSNs is presented. First, a multi-agent-based architecture for WSNs is proposed and a mathematical model of dynamic alliance is constructed for the task allocation problem. Then an effective discrete particle swarm optimization (PSO) algorithm for the dynamic alliance (DPSO-DA) with a well-designed particle position code and fitness function is proposed. A mutation operator which can effectively improve the algorithm's ability of global search and population diversity is also introduced in this algorithm. Finally, the simulation results show that the proposed solution can achieve significant better performance than other algorithms. PMID:22163971

  5. RheoStim: Development of an Adaptive Multi-Sensor to Prevent Venous Stasis

    PubMed Central

    Weyer, Sören; Weishaupt, Fabio; Kleeberg, Christian; Leonhardt, Steffen; Teichmann, Daniel

    2016-01-01

    Chronic venous insufficiency of the lower limbs is often underestimated and, in the absence of therapy, results in increasingly severe complications, including therapy-resistant tissue defects. Therefore, early diagnosis and adequate therapy is of particular importance. External counter pulsation (ECP) therapy is a method used to assist the venous system. The main principle of ECP is to squeeze the inner leg vessels by muscle contractions, which are evoked by functional electrical stimulation. A new adaptive trigger method is proposed, which improves and supplements the current therapeutic options by means of pulse synchronous electro-stimulation of the muscle pump. For this purpose, blood flow is determined by multi-sensor plethysmography. The hardware design and signal processing of this novel multi-sensor plethysmography device are introduced. The merged signal is used to determine the phase of the cardiac cycle, to ensure stimulation of the muscle pump during the filling phase of the heart. The pulse detection of the system is validated against a gold standard and provides a sensitivity of 98% and a false-negative rate of 2% after physical exertion. Furthermore, flow enhancement of the system has been validated by duplex ultrasonography. The results show a highly increased blood flow in the popliteal vein at the knee. PMID:27023544

  6. Adaptive Data Gathering in Mobile Sensor Networks Using Speedy Mobile Elements.

    PubMed

    Lai, Yongxuan; Xie, Jinshan; Lin, Ziyu; Wang, Tian; Liao, Minghong

    2015-01-01

    Data gathering is a key operator for applications in wireless sensor networks; yet it is also a challenging problem in mobile sensor networks when considering that all nodes are mobile and the communications among them are opportunistic. This paper proposes an efficient data gathering scheme called ADG that adopts speedy mobile elements as the mobile data collector and takes advantage of the movement patterns of the network. ADG first extracts the network meta-data at initial epochs, and calculates a set of proxy nodes based on the meta-data. Data gathering is then mapped into the Proxy node Time Slot Allocation (PTSA) problem that schedules the time slots and orders, according to which the data collector could gather the maximal amount of data within a limited period. Finally, the collector follows the schedule and picks up the sensed data from the proxy nodes through one hop of message transmissions. ADG learns the period when nodes are relatively stationary, so that the collector is able to pick up the data from them during the limited data gathering period. Moreover, proxy nodes and data gathering points could also be timely updated so that the collector could adapt to the change of node movements. Extensive experimental results show that the proposed scheme outperforms other data gathering schemes on the cost of message transmissions and the data gathering rate, especially under the constraint of limited data gathering period. PMID:26389903

  7. Adaptive Data Gathering in Mobile Sensor Networks Using Speedy Mobile Elements

    PubMed Central

    Lai, Yongxuan; Xie, Jinshan; Lin, Ziyu; Wang, Tian; Liao, Minghong

    2015-01-01

    Data gathering is a key operator for applications in wireless sensor networks; yet it is also a challenging problem in mobile sensor networks when considering that all nodes are mobile and the communications among them are opportunistic. This paper proposes an efficient data gathering scheme called ADG that adopts speedy mobile elements as the mobile data collector and takes advantage of the movement patterns of the network. ADG first extracts the network meta-data at initial epochs, and calculates a set of proxy nodes based on the meta-data. Data gathering is then mapped into the Proxy node Time Slot Allocation (PTSA) problem that schedules the time slots and orders, according to which the data collector could gather the maximal amount of data within a limited period. Finally, the collector follows the schedule and picks up the sensed data from the proxy nodes through one hop of message transmissions. ADG learns the period when nodes are relatively stationary, so that the collector is able to pick up the data from them during the limited data gathering period. Moreover, proxy nodes and data gathering points could also be timely updated so that the collector could adapt to the change of node movements. Extensive experimental results show that the proposed scheme outperforms other data gathering schemes on the cost of message transmissions and the data gathering rate, especially under the constraint of limited data gathering period. PMID:26389903

  8. Vibration suppression in cutting tools using collocated piezoelectric sensors/actuators with an adaptive control algorithm

    SciTech Connect

    Radecki, Peter P; Farinholt, Kevin M; Park, Gyuhae; Bement, Matthew T

    2008-01-01

    The machining process is very important in many engineering applications. In high precision machining, surface finish is strongly correlated with vibrations and the dynamic interactions between the part and the cutting tool. Parameters affecting these vibrations and dynamic interactions, such as spindle speed, cut depth, feed rate, and the part's material properties can vary in real-time, resulting in unexpected or undesirable effects on the surface finish of the machining product. The focus of this research is the development of an improved machining process through the use of active vibration damping. The tool holder employs a high bandwidth piezoelectric actuator with an adaptive positive position feedback control algorithm for vibration and chatter suppression. In addition, instead of using external sensors, the proposed approach investigates the use of a collocated piezoelectric sensor for measuring the dynamic responses from machining processes. The performance of this method is evaluated by comparing the surface finishes obtained with active vibration control versus baseline uncontrolled cuts. Considerable improvement in surface finish (up to 50%) was observed for applications in modern day machining.

  9. Fleet Assignment Using Collective Intelligence

    NASA Technical Reports Server (NTRS)

    Antoine, Nicolas E.; Bieniawski, Stefan R.; Kroo, Ilan M.; Wolpert, David H.

    2004-01-01

    Product distribution theory is a new collective intelligence-based framework for analyzing and controlling distributed systems. Its usefulness in distributed stochastic optimization is illustrated here through an airline fleet assignment problem. This problem involves the allocation of aircraft to a set of flights legs in order to meet passenger demand, while satisfying a variety of linear and non-linear constraints. Over the course of the day, the routing of each aircraft is determined in order to minimize the number of required flights for a given fleet. The associated flow continuity and aircraft count constraints have led researchers to focus on obtaining quasi-optimal solutions, especially at larger scales. In this paper, the authors propose the application of this new stochastic optimization algorithm to a non-linear objective cold start fleet assignment problem. Results show that the optimizer can successfully solve such highly-constrained problems (130 variables, 184 constraints).

  10. Fleet Assignment Using Collective Intelligence

    NASA Technical Reports Server (NTRS)

    Antoine, Nicolas E.; Bieniawski, Stefan R.; Kroo, Ilan M.; Wolpert, David H.

    2004-01-01

    Airline fleet assignment involves the allocation of aircraft to a set of flights legs in order to meet passenger demand, while satisfying a variety of constraints. Over the course of the day, the routing of each aircraft is determined in order to minimize the number of required flights for a given fleet. The associated flow continuity and aircraft count constraints have led researchers to focus on obtaining quasi-optimal solutions, especially at larger scales. In this paper, the authors propose the application of an agent-based integer optimization algorithm to a "cold start" fleet assignment problem. Results show that the optimizer can successfully solve such highly- constrained problems (129 variables, 184 constraints).

  11. An Adaptive Jitter Mechanism for Reactive Route Discovery in Sensor Networks

    PubMed Central

    Cordero, Juan Antonio; Yi, Jiazi; Clausen, Thomas

    2014-01-01

    This paper analyses the impact of jitter when applied to route discovery in reactive (on-demand) routing protocols. In multi-hop non-synchronized wireless networks, jitter—a small, random variation in the timing of message emission—is commonly employed, as a means to avoid collisions of simultaneous transmissions by adjacent routers over the same channel. In a reactive routing protocol for sensor and ad hoc networks, jitter is recommended during the route discovery process, specifically, during the network-wide flooding of route request messages, in order to avoid collisions. Commonly, a simple uniform jitter is recommended. Alas, this is not without drawbacks: when applying uniform jitter to the route discovery process, an effect called delay inversion is observed. This paper, first, studies and quantifies this delay inversion effect. Second, this paper proposes an adaptive jitter mechanism, designed to alleviate the delay inversion effect and thereby to reduce the route discovery overhead and (ultimately) allow the routing protocol to find more optimal paths, as compared to uniform jitter. This paper presents both analytical and simulation studies, showing that the proposed adaptive jitter can effectively decrease the cost of route discovery and increase the path quality. PMID:25111238

  12. An Adaptive Channel Access Method for Dynamic Super Dense Wireless Sensor Networks.

    PubMed

    Lei, Chunyang; Bie, Hongxia; Fang, Gengfa; Zhang, Xuekun

    2015-01-01

    Super dense and distributed wireless sensor networks have become very popular with the development of small cell technology, Internet of Things (IoT), Machine-to-Machine (M2M) communications, Vehicular-to-Vehicular (V2V) communications and public safety networks. While densely deployed wireless networks provide one of the most important and sustainable solutions to improve the accuracy of sensing and spectral efficiency, a new channel access scheme needs to be designed to solve the channel congestion problem introduced by the high dynamics of competing nodes accessing the channel simultaneously. In this paper, we firstly analyzed the channel contention problem using a novel normalized channel contention analysis model which provides information on how to tune the contention window according to the state of channel contention. We then proposed an adaptive channel contention window tuning algorithm in which the contention window tuning rate is set dynamically based on the estimated channel contention level. Simulation results show that our proposed adaptive channel access algorithm based on fast contention window tuning can achieve more than 95 % of the theoretical optimal throughput and 0 . 97 of fairness index especially in dynamic and dense networks. PMID:26633421

  13. An adaptive jitter mechanism for reactive route discovery in sensor networks.

    PubMed

    Cordero, Juan Antonio; Yi, Jiazi; Clausen, Thomas

    2014-01-01

    This paper analyses the impact of jitter when applied to route discovery in reactive (on-demand) routing protocols. In multi-hop non-synchronized wireless networks, jitter--a small, random variation in the timing of message emission--is commonly employed, as a means to avoid collisions of simultaneous transmissions by adjacent routers over the same channel. In a reactive routing protocol for sensor and ad hoc networks, jitter is recommended during the route discovery process, specifically, during the network-wide flooding of route request messages, in order to avoid collisions. Commonly, a simple uniform jitter is recommended. Alas, this is not without drawbacks: when applying uniform jitter to the route discovery process, an effect called delay inversion is observed. This paper, first, studies and quantifies this delay inversion effect. Second, this paper proposes an adaptive jitter mechanism, designed to alleviate the delay inversion effect and thereby to reduce the route discovery overhead and (ultimately) allow the routing protocol to find more optimal paths, as compared to uniform jitter. This paper presents both analytical and simulation studies, showing that the proposed adaptive jitter can effectively decrease the cost of route discovery and increase the path quality. PMID:25111238

  14. An Adaptive Channel Access Method for Dynamic Super Dense Wireless Sensor Networks

    PubMed Central

    Lei, Chunyang; Bie, Hongxia; Fang, Gengfa; Zhang, Xuekun

    2015-01-01

    Super dense and distributed wireless sensor networks have become very popular with the development of small cell technology, Internet of Things (IoT), Machine-to-Machine (M2M) communications, Vehicular-to-Vehicular (V2V) communications and public safety networks. While densely deployed wireless networks provide one of the most important and sustainable solutions to improve the accuracy of sensing and spectral efficiency, a new channel access scheme needs to be designed to solve the channel congestion problem introduced by the high dynamics of competing nodes accessing the channel simultaneously. In this paper, we firstly analyzed the channel contention problem using a novel normalized channel contention analysis model which provides information on how to tune the contention window according to the state of channel contention. We then proposed an adaptive channel contention window tuning algorithm in which the contention window tuning rate is set dynamically based on the estimated channel contention level. Simulation results show that our proposed adaptive channel access algorithm based on fast contention window tuning can achieve more than 95% of the theoretical optimal throughput and 0.97 of fairness index especially in dynamic and dense networks. PMID:26633421

  15. Mimicking the End Organ Architecture of Slowly Adapting Type I Afferents May Increase the Durability of Artificial Touch Sensors

    PubMed Central

    Lesniak, Daine R.; Gerling, Gregory J.

    2015-01-01

    In effort to mimic the sensitivity and efficient information transfer of natural tactile afferents, recent work has combined force transducers and computational models of mechanosensitive afferents. Sensor durability, another feature important to sensor design, might similarly capitalize upon biological rules. In particular, gains in sensor durability might leverage insight from the compound end organ of the slowly adapting type I afferent, especially its multiple sites of spike initiation that reset each other. This work develops models of compound spiking sensors using a computational network of transduction functions and leaky integrate and fire models (together a spike encoder, the software element of a compound spiking sensor), informed by the output of an existing force transducer (hardware sensing elements of a compound spiking sensor). Individual force transducer failures are simulated with and without resetting between spike encoders to test the importance of both resetting and configuration on system durability. The results indicate that the resetting of adjacent spike encoders, upon the firing of a spike by any one, is an essential mechanism to maintain a stable overall response in the midst of transducer failure. Furthermore, results suggest that when resetting is enabled, the durability of a compound sensor is maximized when individual transducers are paired with spike encoders and multiple, paired units are employed. To explore these ideas more fully, use cases examine the design of a compound sensor to either reach a target lifetime with a set probability or determine how often to schedule maintenance to control the probability of failure. PMID:25705703

  16. National Clean Fleets Partnership (Fact Sheet)

    SciTech Connect

    Not Available

    2014-01-01

    Clean Cities' National Clean Fleets Partnership establishes strategic alliances with large fleets to help them explore and adopt alternative fuels and fuel economy measures to cut petroleum use. The initiative leverages the strength of nearly 100 Clean Cities coalitions, nearly 18,000 stakeholders, and more than 20 years of experience. It provides fleets with top-level support, technical assistance, robust tools and resources, and public acknowledgement to help meet and celebrate fleets' petroleum-use reductions.

  17. 30 CFR 56.19037 - Fleet angles.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Fleet angles. 56.19037 Section 56.19037 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND... Sheaves § 56.19037 Fleet angles. Fleet angles on hoists installed after November 15, 1979, shall not...

  18. 30 CFR 57.19037 - Fleet angles.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Fleet angles. 57.19037 Section 57.19037 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND... Sheaves § 57.19037 Fleet angles. Fleet angles on hoists installed after November 15, 1979, shall not...

  19. 30 CFR 57.19037 - Fleet angles.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Fleet angles. 57.19037 Section 57.19037 Mineral... Sheaves § 57.19037 Fleet angles. Fleet angles on hoists installed after November 15, 1979, shall not be greater than one and one-half degrees for smooth drums or two degrees for grooved drums....

  20. Nuclear fleet: Today and tomorrow

    SciTech Connect

    Levin, B.M.; Kovalenko, V.K.; Sinyaev, A.K.

    1993-12-31

    Many years of operational experience have shown advantages of nuclear liner icebreakers over those burning fossil fuels primarily in ensuring reliable and stable shipping along the North Sea Route with an extended navigation season being realized. The advantages of the nuclear fleet are described.

  1. Adaptive Multi-sensor Data Fusion Model for In-situ Exploration of Mars

    NASA Astrophysics Data System (ADS)

    Schneiderman, T.; Sobron, P.

    2014-12-01

    Laser Raman spectroscopy (LRS) and laser-induced breakdown spectroscopy (LIBS) can be used synergistically to characterize the geochemistry and mineralogy of potential microbial habitats and biosignatures. The value of LRS and LIBS has been recognized by the planetary science community: (i) NASA's Mars2020 mission features a combined LRS-LIBS instrument, SuperCam, and an LRS instrument, SHERLOC; (ii) an LRS instrument, RLS, will fly on ESA's 2018 ExoMars mission. The advantages of combining LRS and LIBS are evident: (1) LRS/LIBS can share hardware components; (2) LIBS reveals the relative concentration of major (and often trace) elements present in a sample; and (3) LRS yields information on the individual mineral species and their chemical/structural nature. Combining data from LRS and LIBS enables definitive mineral phase identification with precise chemical characterization of major, minor, and trace mineral species. New approaches to data processing are needed to analyze large amounts of LRS+LIBS data efficiently and maximize the scientific return of integrated measurements. Multi-sensor data fusion (MSDF) is a method that allows for robust sample identification through automated acquisition, processing, and combination of data. It optimizes information usage, yielding a more robust characterization of a target than could be acquired through single sensor use. We have developed a prototype fuzzy logic adaptive MSDF model aimed towards the unsupervised characterization of Martian habitats and their biosignatures using LRS and LIBS datasets. Our model also incorporates fusion of microimaging (MI) data - critical for placing analyses in geological and spatial context. Here, we discuss the performance of our novel MSDF model and demonstrate that automated quantification of the salt abundance in sulfate/clay/phyllosilicate mixtures is possible through data fusion of collocated LRS, LIBS, and MI data.

  2. Continuous and embedded learning in autonomous vehicles: adapting to sensor failures

    NASA Astrophysics Data System (ADS)

    Schultz, Alan C.; Grefenstette, John J.

    2000-07-01

    This project describes an approach to creating autonomous systems that can continue to learn throughout their lives, that is, to be adaptive to changes in the environment and in their own capabilities. Evolutionary learning methods have been found to be useful in several areas in the development of autonomous vehicles. In our research, evolutionary algorithms are used to explore the alternative robot behaviors within a simulation model as a way of reducing the overall knowledge engineering effort. The learned behaviors are then tested in the actual robot and the results compared. Initial research demonstrated the ability to learn reasonable complex robot behaviors such as herding, and navigation and collision avoidance using this offline learning approach. In this work, the vehicle is always exploring different strategies via an internal simulation model; the simulation in term, is changing over time to better match the world. This model, which we call Continuous and Embedded Learning (also referred to as Anytime Learning), is a general approach to continuous learning in a changing environment. The agent's learning module continuously tests new strategies against a simulation model of the task environment, and dynamically updates the knowledge base used by the agent on the basis of the results. The execution module controls the agent's interaction with the environment, and includes a monitor that can dynamically modify the simulation model based on its observations of the environment. When a simulation model is modified, the learning process continues on the modified model. The learning system is assume to operate indefinitely, and the execution system uses the results of learning as they become available. Early experimental studies demonstrate a robot that can learn to adapt to failures in its sonar sensors.

  3. Adaptive Multi-Node Multiple Input and Multiple Output (MIMO) Transmission for Mobile Wireless Multimedia Sensor Networks

    PubMed Central

    Cho, Sunghyun; Choi, Ji-Woong; You, Cheolwoo

    2013-01-01

    Mobile wireless multimedia sensor networks (WMSNs), which consist of mobile sink or sensor nodes and use rich sensing information, require much faster and more reliable wireless links than static wireless sensor networks (WSNs). This paper proposes an adaptive multi-node (MN) multiple input and multiple output (MIMO) transmission to improve the transmission reliability and capacity of mobile sink nodes when they experience spatial correlation. Unlike conventional single-node (SN) MIMO transmission, the proposed scheme considers the use of transmission antennas from more than two sensor nodes. To find an optimal antenna set and a MIMO transmission scheme, a MN MIMO channel model is introduced first, followed by derivation of closed-form ergodic capacity expressions with different MIMO transmission schemes, such as space-time transmit diversity coding and spatial multiplexing. The capacity varies according to the antenna correlation and the path gain from multiple sensor nodes. Based on these statistical results, we propose an adaptive MIMO mode and antenna set switching algorithm that maximizes the ergodic capacity of mobile sink nodes. The ergodic capacity of the proposed scheme is compared with conventional SN MIMO schemes, where the gain increases as the antenna correlation and path gain ratio increase. PMID:24152920

  4. Adaptive multi-node multiple input and multiple output (MIMO) transmission for mobile wireless multimedia sensor networks.

    PubMed

    Cho, Sunghyun; Choi, Ji-Woong; You, Cheolwoo

    2013-01-01

    Mobile wireless multimedia sensor networks (WMSNs), which consist of mobile sink or sensor nodes and use rich sensing information, require much faster and more reliable wireless links than static wireless sensor networks (WSNs). This paper proposes an adaptive multi-node (MN) multiple input and multiple output (MIMO) transmission to improve the transmission reliability and capacity of mobile sink nodes when they experience spatial correlation. Unlike conventional single-node (SN) MIMO transmission, the proposed scheme considers the use of transmission antennas from more than two sensor nodes. To find an optimal antenna set and a MIMO transmission scheme, a MN MIMO channel model is introduced first, followed by derivation of closed-form ergodic capacity expressions with different MIMO transmission schemes, such as space-time transmit diversity coding and spatial multiplexing. The capacity varies according to the antenna correlation and the path gain from multiple sensor nodes. Based on these statistical results, we propose an adaptive MIMO mode and antenna set switching algorithm that maximizes the ergodic capacity of mobile sink nodes. The ergodic capacity of the proposed scheme is compared with conventional SN MIMO schemes, where the gain increases as the antenna correlation and path gain ratio increase. PMID:24152920

  5. Identification of Hot Moments and Hot Spots for Real-Time Adaptive Control of Multi-scale Environmental Sensor Networks

    NASA Astrophysics Data System (ADS)

    Wietsma, T.; Minsker, B. S.

    2012-12-01

    Increased sensor throughput combined with decreasing hardware costs has led to a disruptive growth in data volume. This disruption, popularly termed "the data deluge," has placed new demands for cyberinfrastructure and information technology skills among researchers in many academic fields, including the environmental sciences. Adaptive sampling has been well established as an effective means of improving network resource efficiency (energy, bandwidth) without sacrificing sample set quality relative to traditional uniform sampling. However, using adaptive sampling for the explicit purpose of improving resolution over events -- situations displaying intermittent dynamics and unique hydrogeological signatures -- is relatively new. In this paper, we define hot spots and hot moments in terms of sensor signal activity as measured through discrete Fourier analysis. Following this frequency-based approach, we apply the Nyquist-Shannon sampling theorem, a fundamental contribution from signal processing that led to the field of information theory, for analysis of uni- and multivariate environmental signal data. In the scope of multi-scale environmental sensor networks, we present several sampling control algorithms, derived from the Nyquist-Shannon theorem, that operate at local (field sensor), regional (base station for aggregation of field sensor data), and global (Cloud-based, computationally intensive models) scales. Evaluated over soil moisture data, results indicate significantly greater sample density during precipitation events while reducing overall sample volume. Using these algorithms as indicators rather than control mechanisms, we also discuss opportunities for spatio-temporal modeling as a tool for planning/modifying sensor network deployments. Locally adaptive model based on Nyquist-Shannon sampling theorem Pareto frontiers for local, regional, and global models relative to uniform sampling. Objectives are (1) overall sampling efficiency and (2) sampling

  6. National Clean Fleets Partnership (Fact Sheet)

    SciTech Connect

    Not Available

    2012-01-01

    Provides an overview of Clean Cities National Clean Fleets Partnership (NCFP). The NCFP is open to large private-sector companies that have fleet operations in multiple states. Companies that join the partnership receive customized assistance to reduce petroleum use through increased efficiency and use of alternative fuels. This initiative provides fleets with specialized resources, expertise, and support to successfully incorporate alternative fuels and fuel-saving measures into their operations. The National Clean Fleets Partnership builds on the established success of DOE's Clean Cities program, which reduces petroleum consumption at the community level through a nationwide network of coalitions that work with local stakeholders. Developed with input from fleet managers, industry representatives, and Clean Cities coordinators, the National Clean Fleets Partnership goes one step further by working with large private-sector fleets.

  7. A Star Recognition Method Based on the Adaptive Ant Colony Algorithm for Star Sensors

    PubMed Central

    Quan, Wei; Fang, Jiancheng

    2010-01-01

    A new star recognition method based on the Adaptive Ant Colony (AAC) algorithm has been developed to increase the star recognition speed and success rate for star sensors. This method draws circles, with the center of each one being a bright star point and the radius being a special angular distance, and uses the parallel processing ability of the AAC algorithm to calculate the angular distance of any pair of star points in the circle. The angular distance of two star points in the circle is solved as the path of the AAC algorithm, and the path optimization feature of the AAC is employed to search for the optimal (shortest) path in the circle. This optimal path is used to recognize the stellar map and enhance the recognition success rate and speed. The experimental results show that when the position error is about 50″, the identification success rate of this method is 98% while the Delaunay identification method is only 94%. The identification time of this method is up to 50 ms. PMID:22294908

  8. A novel adaptive, real-time algorithm to detect gait events from wearable sensors.

    PubMed

    Chia Bejarano, Noelia; Ambrosini, Emilia; Pedrocchi, Alessandra; Ferrigno, Giancarlo; Monticone, Marco; Ferrante, Simona

    2015-05-01

    A real-time, adaptive algorithm based on two inertial and magnetic sensors placed on the shanks was developed for gait-event detection. For each leg, the algorithm detected the Initial Contact (IC), as the minimum of the flexion/extension angle, and the End Contact (EC) and the Mid-Swing (MS), as minimum and maximum of the angular velocity, respectively. The algorithm consisted of calibration, real-time detection, and step-by-step update. Data collected from 22 healthy subjects (21 to 85 years) walking at three self-selected speeds were used to validate the algorithm against the GaitRite system. Comparable levels of accuracy and significantly lower detection delays were achieved with respect to other published methods. The algorithm robustness was tested on ten healthy subjects performing sudden speed changes and on ten stroke subjects (43 to 89 years). For healthy subjects, F1-scores of 1 and mean detection delays lower than 14 ms were obtained. For stroke subjects, F1-scores of 0.998 and 0.944 were obtained for IC and EC, respectively, with mean detection delays always below 31 ms. The algorithm accurately detected gait events in real time from a heterogeneous dataset of gait patterns and paves the way for the design of closed-loop controllers for customized gait trainings and/or assistive devices. PMID:25069118

  9. An Adaptive Sensor Data Segments Selection Method for Wearable Health Care Services.

    PubMed

    Chen, Shih-Yeh; Lai, Chin-Feng; Hwang, Ren-Hung; Lai, Ying-Hsun; Wang, Ming-Shi

    2015-12-01

    As cloud computing and wearable devices technologies mature, relevant services have grown more and more popular in recent years. The healthcare field is one of the popular services for this technology that adopts wearable devices to sense signals of negative physiological events, and to notify users. The development and implementation of long-term healthcare monitoring that can prevent or quickly respond to the occurrence of disease and accidents present an interesting challenge for computing power and energy limits. This study proposed an adaptive sensor data segments selection method for wearable health care services, and considered the sensing frequency of the various signals from human body, as well as the data transmission among the devices. The healthcare service regulates the sensing frequency of devices by considering the overall cloud computing environment and the sensing variations of wearable health care services. The experimental results show that the proposed service can effectively transmit the sensing data and prolong the overall lifetime of health care services. PMID:26490152

  10. A star recognition method based on the Adaptive Ant Colony algorithm for star sensors.

    PubMed

    Quan, Wei; Fang, Jiancheng

    2010-01-01

    A new star recognition method based on the Adaptive Ant Colony (AAC) algorithm has been developed to increase the star recognition speed and success rate for star sensors. This method draws circles, with the center of each one being a bright star point and the radius being a special angular distance, and uses the parallel processing ability of the AAC algorithm to calculate the angular distance of any pair of star points in the circle. The angular distance of two star points in the circle is solved as the path of the AAC algorithm, and the path optimization feature of the AAC is employed to search for the optimal (shortest) path in the circle. This optimal path is used to recognize the stellar map and enhance the recognition success rate and speed. The experimental results show that when the position error is about 50″, the identification success rate of this method is 98% while the Delaunay identification method is only 94%. The identification time of this method is up to 50 ms. PMID:22294908

  11. Auto gain control of EMCCD in Shack-Hartmann wavefront sensor for adaptive optics

    NASA Astrophysics Data System (ADS)

    Zhu, Zhaoyi; Li, Dayu; Hu, Lifa; Mu, QuanQuan; Cao, Zhaoliang; Wang, Yukun; Wang, Shaoxin; Xuan, Li

    2016-12-01

    Electron multiplying charge-coupled-device (EMCCD) applied in Shack-Hartmann wavefront sensor (S-H WFS) makes the wavefront sensing more efficient for adaptive optics (AO). However when the brightness of the observed target changes in large ranges in a few minutes, a fixed electron multiplying (EM) gain may not be optimum. Thus an auto-gain-control (AGC) method based on the spots image of the S-H WFS is proposed. The designed control value is the average value of the maximum signals of all the light spots in a frame. It has been demonstrated in the experiments that the control value is sensitive to the change of the target brightness, and is stable in the presence of detecting noises and turbulence influence. The goal value for control is predetermined based on the linear relation of the signal with the EM gain and the number of photons collected in sub-apertures. The conditions of the self-protection of the EMCCD are also considered for the goal value. Simulations and experiments indicate that the proposed control method is efficient, and keeps the sensing in a high SNR which reaches the upper SNR limit when sensing with EMCCD. The self-protection of the EMCCD is avoided during the whole sensing process.

  12. Self-adapting root-MUSIC algorithm and its real-valued formulation for acoustic vector sensor array

    NASA Astrophysics Data System (ADS)

    Wang, Peng; Zhang, Guo-jun; Xue, Chen-yang; Zhang, Wen-dong; Xiong, Ji-jun

    2012-12-01

    In this paper, based on the root-MUSIC algorithm for acoustic pressure sensor array, a new self-adapting root-MUSIC algorithm for acoustic vector sensor array is proposed by self-adaptive selecting the lead orientation vector, and its real-valued formulation by Forward-Backward(FB) smoothing and real-valued inverse covariance matrix is also proposed, which can reduce the computational complexity and distinguish the coherent signals. The simulation experiment results show the better performance of two new algorithm with low Signal-to-Noise (SNR) in direction of arrival (DOA) estimation than traditional MUSIC algorithm, and the experiment results using MEMS vector hydrophone array in lake trails show the engineering practicability of two new algorithms.

  13. A cask fleet operations study

    SciTech Connect

    Not Available

    1988-03-01

    This document describes the cask fleet currently available to transport spent nuclear fuels. The report describes the proposed operational procedures for these casks and the vehicles intended to transport them. Included are techniques for loading the cask, lifting it onto the transport vehicle, preparing the invoices, and unloading the cask at the destination. The document concludes with a discussion on the maintenance and repair of the casks. (tem) 29 figs.

  14. A novel method using adaptive hidden semi-Markov model for multi-sensor monitoring equipment health prognosis

    NASA Astrophysics Data System (ADS)

    Liu, Qinming; Dong, Ming; Lv, Wenyuan; Geng, Xiuli; Li, Yupeng

    2015-12-01

    Health prognosis for equipment is considered as a key process of the condition-based maintenance strategy. This paper presents an integrated framework for multi-sensor equipment diagnosis and prognosis based on adaptive hidden semi-Markov model (AHSMM). Unlike hidden semi-Markov model (HSMM), the basic algorithms in an AHSMM are first modified in order for decreasing computation and space complexity. Then, the maximum likelihood linear regression transformations method is used to train the output and duration distributions to re-estimate all unknown parameters. The AHSMM is used to identify the hidden degradation state and obtain the transition probabilities among health states and durations. Finally, through the proposed hazard rate equations, one can predict the useful remaining life of equipment with multi-sensor information. Our main results are verified in real world applications: monitoring hydraulic pumps from Caterpillar Inc. The results show that the proposed methods are more effective for multi-sensor monitoring equipment health prognosis.

  15. Wavefront response matrix for closed-loop adaptive optics system based on non-modulation pyramid wavefront sensor

    NASA Astrophysics Data System (ADS)

    Wang, Jianxin; Bai, Fuzhong; Ning, Yu; Li, Fei; Jiang, Wenhan

    2012-06-01

    Pyramid wavefront sensor (PWFS) is a kind of wavefront sensor with high spatial resolution and high energy utilization. In this paper an adaptive optics system with PWFS as wavefront sensor and liquid-crystal spatial light modulator (LC-SLM) as wavefront corrector is built in the laboratory. The wavefront response matrix is a key element in the close-loop operation. It can be obtained by measuring the real response to given aberrations, which is easily contaminated by noise and influenced by the inherent aberration in the optical system. A kind of analytic solution of response matrix is proposed, with which numerical simulation and experiment are also implemented to verify the performance of closed-loop correction of static aberration based on linear reconstruction theory. Results show that this AO system with the proposed matrix can work steadily in closed-loop operation.

  16. Aircraft Anomaly Detection Using Performance Models Trained on Fleet Data

    NASA Technical Reports Server (NTRS)

    Gorinevsky, Dimitry; Matthews, Bryan L.; Martin, Rodney

    2012-01-01

    This paper describes an application of data mining technology called Distributed Fleet Monitoring (DFM) to Flight Operational Quality Assurance (FOQA) data collected from a fleet of commercial aircraft. DFM transforms the data into aircraft performance models, flight-to-flight trends, and individual flight anomalies by fitting a multi-level regression model to the data. The model represents aircraft flight performance and takes into account fixed effects: flight-to-flight and vehicle-to-vehicle variability. The regression parameters include aerodynamic coefficients and other aircraft performance parameters that are usually identified by aircraft manufacturers in flight tests. Using DFM, the multi-terabyte FOQA data set with half-million flights was processed in a few hours. The anomalies found include wrong values of competed variables, (e.g., aircraft weight), sensor failures and baises, failures, biases, and trends in flight actuators. These anomalies were missed by the existing airline monitoring of FOQA data exceedances.

  17. Evolution of Heat Sensors Drove Shifts in Thermosensation between Xenopus Species Adapted to Different Thermal Niches.

    PubMed

    Saito, Shigeru; Ohkita, Masashi; Saito, Claire T; Takahashi, Kenji; Tominaga, Makoto; Ohta, Toshio

    2016-05-20

    Temperature is one of the most critical environmental factors affecting survival, and thus species that inhabit different thermal niches have evolved thermal sensitivities suitable for their respective habitats. During the process of shifting thermal niches, various types of genes expressed in diverse tissues, including those of the peripheral to central nervous systems, are potentially involved in the evolutionary changes in thermosensation. To elucidate the molecular mechanisms behind the evolution of thermosensation, thermal responses were compared between two species of clawed frogs (Xenopus laevis and Xenopus tropicalis) adapted to different thermal environments. X. laevis was much more sensitive to heat stimulation than X. tropicalis at the behavioral and neural levels. The activity and sensitivity of the heat-sensing TRPA1 channel were higher in X. laevis compared with those of X. tropicalis The thermal responses of another heat-sensing channel, TRPV1, also differed between the two Xenopus species. The species differences in Xenopus TRPV1 heat responses were largely determined by three amino acid substitutions located in the first three ankyrin repeat domains, known to be involved in the regulation of rat TRPV1 activity. In addition, Xenopus TRPV1 exhibited drastic species differences in sensitivity to capsaicin, contained in chili peppers, between the two Xenopus species. Another single amino acid substitution within Xenopus TRPV1 is responsible for this species difference, which likely alters the neural and behavioral responses to capsaicin. These combined subtle amino acid substitutions in peripheral thermal sensors potentially serve as a driving force for the evolution of thermal and chemical sensation. PMID:27022021

  18. CNG and Fleets: Building Your Business Case

    SciTech Connect

    2015-09-01

    Two online resources help fleets evaluate the economic soundness of a compressed natural gas program. The National Renewable Energy Laboratory's (NREL's) Vehicle Infrastructure and Cash-Flow Evaluation (VICE 2.0) model and the accompanying report, Building a Business Case for Compressed Natural Gas in Fleet Applications, are uniquely designed for fleet managers considering an investment in CNG and can help ensure wise investment decisions about CNG vehicles and infrastructure.

  19. Improving the Forecast Accuracy of an Ocean Observation and Prediction System by Adaptive Control of the Sensor Network

    NASA Astrophysics Data System (ADS)

    Talukder, A.; Panangadan, A. V.; Blumberg, A. F.; Herrington, T.; Georgas, N.

    2008-12-01

    The New York Harbor Observation and Prediction System (NYHOPS) is a real-time, estuarine and coastal ocean observing and modeling system for the New York Harbor and surrounding waters. Real-time measurements from in-situ mobile and stationary sensors in the NYHOPS networks are assimilated into marine forecasts in order to reduce the discrepancy with ground truth. The forecasts are obtained from the ECOMSED hydrodynamic model, a shallow water derivative of the Princeton Ocean Model. Currently, all sensors in the NYHOPS system are operated in a fixed mode with uniform sampling rates. This technology infusion effort demonstrates the use of Model Predictive Control (MPC) to autonomously adapt the operation of both mobile and stationary sensors in response to changing events that are -automatically detected from the ECOMSED forecasts. The controller focuses sensing resources on those regions that are expected to be impacted by the detected events. The MPC approach involves formulating the problem of calculating the optimal sensor parameters as a constrained multi-objective optimization problem. We have developed an objective function that takes into account the spatiotemporal relationship of the in-situ sensor locations and the locations of events detected by the model. Experiments in simulation were carried out using data collected during a freshwater flooding event. The location of the resulting freshwater plume was calculated from the corresponding model forecasts and was used by the MPC controller to derive control parameters for the sensing assets. The operational parameters that are controlled include the sampling rates of stationary sensors, paths of unmanned underwater vehicles (UUVs), and data transfer routes between sensors and the central modeling computer. The simulation experiments show that MPC-based sensor control reduces the RMS error in the forecast by a factor of 380% as compared to uniform sampling. The paths of multiple UUVs were simultaneously

  20. Modeling and simulation of adaptive multimodal optical sensors for target tracking in the visible to near infrared

    NASA Astrophysics Data System (ADS)

    Presnar, Michael D.

    This work investigates an integrated aerial remote sensor design approach to address moving target detection and tracking problems within highly cluttered, dynamic ground-based scenes. Sophisticated simulation methodologies and scene phenomenology validations have resulted in advancements in artificial multimodal truth video synthesis. Complex modeling of novel micro-opto-electro-mechanical systems (MOEMS) devices, optical systems, and detector arrays has resulted in a proof of concept for a state-of-the-art imaging spectropolarimeter sensor model that does not suffer from typical multimodal image registration problems. Test methodology developed for this work provides the ability to quantify performance of a target tracking application with varying ground scenery, flight characteristics, or sensor specifications. The culmination of this research is an end-to-end simulated demonstration of multimodal aerial remote sensing and target tracking. Deeply hidden target recognition is shown to be enhanced through the fusing of panchromatic, hyperspectral, and polarimetric image modalities. The Digital Imaging and Remote Sensing Image Generation model was leveraged to synthesize truth spectropolarimetric sensor-reaching radiance image cubes comprised of coregistered Stokes vector bands in the visible to near-infrared. An intricate synthetic urban scene containing numerous moving vehicular targets was imaged from a virtual sensor aboard an aerial platform encircling a stare point. An adaptive sensor model was designed with a superpixel array of MOEMS devices fabricated atop a division of focal plane detector. Degree of linear polarization (DoLP) imagery is acquired by combining three adjacent micropolarizer outputs within each 2x2 superpixel whose respective transmissions vary with wavelength, relative angle of polarization, and wire-grid spacing. A novel micromirror within each superpixel adaptively relays light between a panchromatic imaging channel and a hyperspectral

  1. Alternative fuelds in urban fleets

    SciTech Connect

    Lindsay, T.

    1994-12-31

    In this presentation the author addresses four main objectives. They are to: discuss programs that are driving the introduction of alternative fuels into fleet operations in urban areas around the country; define alternative fuels; quantify the present use and future projections on alternative fuel vehicles (AVFs) in the Chicago metropolitan statistical area; and discuss benefits of increased use of alternative fuels in urban areas. Factors which touch on these points include: present domestic dependence on petroleum for autos, with usage exceeding production; the large populations in urban areas which do not meet Clean Air Standards; recent legislative initiatives which give guidance and aid in the adoption of such strategies.

  2. Adaptation.

    PubMed

    Broom, Donald M

    2006-01-01

    The term adaptation is used in biology in three different ways. It may refer to changes which occur at the cell and organ level, or at the individual level, or at the level of gene action and evolutionary processes. Adaptation by cells, especially nerve cells helps in: communication within the body, the distinguishing of stimuli, the avoidance of overload and the conservation of energy. The time course and complexity of these mechanisms varies. Adaptive characters of organisms, including adaptive behaviours, increase fitness so this adaptation is evolutionary. The major part of this paper concerns adaptation by individuals and its relationships to welfare. In complex animals, feed forward control is widely used. Individuals predict problems and adapt by acting before the environmental effect is substantial. Much of adaptation involves brain control and animals have a set of needs, located in the brain and acting largely via motivational mechanisms, to regulate life. Needs may be for resources but are also for actions and stimuli which are part of the mechanism which has evolved to obtain the resources. Hence pigs do not just need food but need to be able to carry out actions like rooting in earth or manipulating materials which are part of foraging behaviour. The welfare of an individual is its state as regards its attempts to cope with its environment. This state includes various adaptive mechanisms including feelings and those which cope with disease. The part of welfare which is concerned with coping with pathology is health. Disease, which implies some significant effect of pathology, always results in poor welfare. Welfare varies over a range from very good, when adaptation is effective and there are feelings of pleasure or contentment, to very poor. A key point concerning the concept of individual adaptation in relation to welfare is that welfare may be good or poor while adaptation is occurring. Some adaptation is very easy and energetically cheap and

  3. Clean Cities Helps Fleets Go Green (Fact Sheet)

    SciTech Connect

    Not Available

    2009-08-01

    Green fleet programs, like those in Ohio and Illinois, certify vehicle fleets based on environmental and fuel-use requirements. The programs encourage the use of alternative fuels and provide a way to recognize fleets for participating.

  4. An LPV Adaptive Observer for Updating a Map Applied to an MAF Sensor in a Diesel Engine

    PubMed Central

    Liu, Zhiyuan; Wang, Changhui

    2015-01-01

    In this paper, a new method for mass air flow (MAF) sensor error compensation and an online updating error map (or lookup table) due to installation and aging in a diesel engine is developed. Since the MAF sensor error is dependent on the engine operating point, the error model is represented as a two-dimensional (2D) map with two inputs, fuel mass injection quantity and engine speed. Meanwhile, the 2D map representing the MAF sensor error is described as a piecewise bilinear interpolation model, which can be written as a dot product between the regression vector and parameter vector using a membership function. With the combination of the 2D map regression model and the diesel engine air path system, an LPV adaptive observer with low computational load is designed to estimate states and parameters jointly. The convergence of the proposed algorithm is proven under the conditions of persistent excitation and given inequalities. The observer is validated against the simulation data from engine software enDYNA provided by Tesis. The results demonstrate that the operating point-dependent error of the MAF sensor can be approximated acceptably by the 2D map from the proposed method. PMID:26512675

  5. An LPV Adaptive Observer for Updating a Map Applied to an MAF Sensor in a Diesel Engine.

    PubMed

    Liu, Zhiyuan; Wang, Changhui

    2015-01-01

    In this paper, a new method for mass air flow (MAF) sensor error compensation and an online updating error map (or lookup table) due to installation and aging in a diesel engine is developed. Since the MAF sensor error is dependent on the engine operating point, the error model is represented as a two-dimensional (2D) map with two inputs, fuel mass injection quantity and engine speed. Meanwhile, the 2D map representing the MAF sensor error is described as a piecewise bilinear interpolation model, which can be written as a dot product between the regression vector and parameter vector using a membership function. With the combination of the 2D map regression model and the diesel engine air path system, an LPV adaptive observer with low computational load is designed to estimate states and parameters jointly. The convergence of the proposed algorithm is proven under the conditions of persistent excitation and given inequalities. The observer is validated against the simulation data from engine software enDYNA provided by Tesis. The results demonstrate that the operating point-dependent error of the MAF sensor can be approximated acceptably by the 2D map from the proposed method. PMID:26512675

  6. Adaptive and context-aware detection and classification of potential QoS degradation events in biomedical wireless sensor networks

    NASA Astrophysics Data System (ADS)

    Abreu, Carlos; Miranda, Francisco; Mendes, Paulo M.

    2016-06-01

    The use of wireless sensor networks in healthcare has the potential to enhance the services provided to citizens. In particular, they play an important role in the development of state-of-the-art patient monitoring applications. Nevertheless, due to the critical nature of the data conveyed by such patient monitoring applications, they have to fulfil high standards of quality of service in order to obtain the confidence of all players in the healthcare industry. In such context, vis-à-vis the quality of service being provided by the wireless sensor network, this work presents an adaptive and context-aware method to detect and classify performance degradation events. The proposed method has the ability to catch the most significant and damaging variations on the metrics being used to quantify the quality of service provided by the network without overreacting to small and innocuous variations on the metric's value.

  7. Design and adaptation of miniaturized electrochemical devices integrating carbon nanotube-based sensors to commercial CE equipment.

    PubMed

    Arribas, Alberto Sánchez; Moreno, Mónica; Bermejo, Esperanza; Angeles Lorenzo, M; Zapardiel, Antonio; Chicharro, Manuel

    2009-10-01

    The design of new electrochemical devices integrating carbon nanotube sensors and their adaptation to commercial CE equipments are described. One of these designs was made for using commercial screen-printed electrodes, whereas the second was projected for coupling commercial glassy carbon electrodes. The electrochemical characterization of these devices revealed that their hydrodynamic behaviour is strongly influenced by the electrode modification with multi-wall carbon nanotubes that provided faster and/or more sensitive signals. The analytical applicability of these devices was illustrated for the CZE separation of chlorinated phenols and the MEKC separation of endocrine disruptors, where the use of carbon nanotube sensors has proved to be advantageous when compared with unmodified ones, with good electrocatalytic properties combined with acceptable background currents and a remarkable resistance to passivation. PMID:19757434

  8. Enabling the dynamic coupling between sensor web and Earth system models - The Self-Adaptive Earth Predictive Systems (SEPS) framework

    NASA Astrophysics Data System (ADS)

    di, L.; Yu, G.; Chen, N.

    2007-12-01

    The self-adaptation concept is the central piece of the control theory widely and successfully used in engineering and military systems. Such a system contains a predictor and a measurer. The predictor takes initial condition and makes an initial prediction and the measurer then measures the state of a real world phenomenon. A feedback mechanism is built in that automatically feeds the measurement back to the predictor. The predictor takes the measurement against the prediction to calculate the prediction error and adjust its internal state based on the error. Thus, the predictor learns from the error and makes a more accurate prediction in the next step. By adopting the self-adaptation concept, we proposed the Self-adaptive Earth Predictive System (SEPS) concept for enabling the dynamic coupling between the sensor web and the Earth system models. The concept treats Earth System Models (ESM) and Earth Observations (EO) as integral components of the SEPS coupled by the SEPS framework. EO measures the Earth system state while ESM predicts the evolution of the state. A feedback mechanism processes EO measurements and feeds them into ESM during model runs or as initial conditions. A feed-forward mechanism analyzes the ESM predictions against science goals for scheduling optimized/targeted observations. The SEPS framework automates the Feedback and Feed-forward mechanisms (the FF-loop). Based on open consensus-based standards, a general SEPS framework can be developed for supporting the dynamic, interoperable coupling between ESMs and EO. Such a framework can support the plug-in-and-play capability of both ESMs and diverse sensors and data systems as long as they support the standard interfaces. This presentation discusses the SEPS concept, the service-oriented architecture (SOA) of SEPS framework, standards of choices for the framework, and the implementation. The presentation also presents examples of SEPS to demonstrate dynamic, interoperable, and live coupling of

  9. New six degree of freedom position sensor greatly improves flexible manufacturing -- but will manufacturers adapt?

    SciTech Connect

    Vann, C. S., LLNL

    1998-03-02

    The manufacturing industry needs better multi-dimensional position sensors to keep pace with increased speed and capabilities of automated equipment and robots. The market for laser and vision sensors is growing at a rapid speed; however, most of the robot- mounted sensors are one or two dimensional, three dimensional at most, while the robotics industry has progressed to 6-axis machines, leaving a gross mismatch in its capability to perform and sense the required task. A new laser sensor provides information. on up to six degrees of position, enabling robots to sense as well as it can physically manipulate, and opening the door to vast improvements in flexible manufacturing. To expedite these improvements, the manufacturing industry should take a lead and not let an outdated norm hinder implementation.

  10. RuCool Operational Oceanography: Using a Fleet of Autonomous Ocean Gliders

    NASA Astrophysics Data System (ADS)

    Graver, J.; Jones, C.; Glenn, S.; Kohut, J.; Schofield, O.; Roarty, H.; Aragon, D.; Kerfoot, J.; Haldeman, C.; Yan, A.

    2007-05-01

    At the Rutgers University Coastal Ocean Observation Lab (RU-COOL), we have constructed a shelf-wide ocean observatory to characterize the physical forcing of continental shelf primary productivity in the New York Bight (NYB). The system is anchored by four enabling technologies, which include the international constellation of ocean color satellites, multi-static high frequency long-range surface current radar, real-time telemetry moorings, and long duration autonomous underwater vehicles (AUVs). Operation of the observatory is through a centralized computer network dedicated to receiving, processing and visualizing the real-time data and then disseminating results to both field scientists and ocean forecasters over the World Wide Web. The system was designed to conduct cutting edge research requiring the addition of rapidly evolving technologies, and to serve society by providing sustained data delivered in real-time. Rutgers COOL continues to work closely with Webb Research Corporation (WRC) in testing and development of the Slocum underwater gliders and continues to apply Slocum gliders in field operations spanning the globe. The continued strong collaboration between WRC and Rutgers has led to advances in glider operations and applications. These include deployment/recovery techniques, improvements in durability and reliability, integrated sensors suites, salinity spike removal, and adaptive controls utilized to optimize mission goals and data return. The gliders have gathered numerous data sets including salt intrusions as seen off of New Jersey, plume tracking, biological water sample matching, and operation through Hurricane Ernesto in 2006. This talk will detail recent oceanographic experiments in which the fleet has been deployed and improvements in the operation of these novel robotic vehicles. These experiments, in locations around the world, have resulted in significant new work in operation of underwater gliders and have gathered new and unique data

  11. Experimental Studies on Model Reference Adaptive Control with Integral Action Employing a Rotary Encoder and Tachometer Sensors

    PubMed Central

    Wu, Guo-Qiang; Wu, Shu-Nan; Bai, Yu-Guang; Liu, Lei

    2013-01-01

    In this paper, an adaptive law with an integral action is designed and implemented on a DC motor by employing a rotary encoder and tachometer sensors. The stability is proved by using the Lyapunov function. The tracking errors asymptotically converge to zero according to the Barbalat lemma. The tracking performance is specified by a reference model, the convergence rate of Lyapunov function is specified by the matrix Q and the control action and the state weighting are restricted by the matrix Γ. The experimental results demonstrate the effectiveness of the proposed control. The maximum errors of the position and velocity with the integral action are reduced from 0.4 V and 1.5 V to 0.2 V and 0.4 V, respectively. The adaptive control with the integral action gives satisfactory performance, even when it suffers from input disturbance. PMID:23575034

  12. Adaptive Wireless Ad-hoc Sensor Networks for Long-term and Event-oriented Environmental Monitoring

    NASA Astrophysics Data System (ADS)

    Bumberger, Jan; Mollenhauer, Hannes; Remmler, Paul; Schaedler, Martin; Schima, Robert; Mollenhauer, Olaf; Hutschenreuther, Tino; Toepfer, Hannes; Dietrich, Peter

    2015-04-01

    Ecosystems are often characterized by their high heterogeneity, complexity and dynamic. Hence, single point measurements are often not sufficient for their complete representation. The application of wireless sensor networks in terrestrial and aquatic environmental systems offer significant benefits as a better consideration to the local test conditions, due to the simple adjustment of the sensor distribution, the sensor types and the sample rate. Another advantage of wireless ad-hoc sensor networks is their self-organizing behavior, resulting in a major reduction in installation and operation costs and time. In addition, individual point measurements with a sensor are significantly improved by measuring at several points continuously. In this work a concept and realization for Long-term ecosystem research is given in the field monitoring of micrometeorology and soil parameters for the interaction of biotic and abiotic processes. This long term analyses are part of the Global Change Experimental Facility (GCEF), a large field-based experimental platform to assess the effects of climate change on ecosystem functions and processes under different land-use scenarios. Regarding to the adaptive behavior of the network, also a mobile version was developed to overcome the lack of information of temporally and spatially fixed measurements for the detection and recording of highly dynamic or time limited processes. First results of different field campaigns are given to present the potentials and limitations of this application in environmental science, especially for the monitoring of the interaction of biotic and abiotic processes, soil-atmosphere interaction and the validation of remote sensing data.

  13. Adaptive Wireless Ad-hoc Sensor Networks for Long-term and Event-oriented Environmental Monitoring

    NASA Astrophysics Data System (ADS)

    Bumberger, Jan; Mollenhauer, Hannes; Remmler, Paul; Chirila, Andrei Marian; Mollenhauer, Olaf; Hutschenreuther, Tino; Toepfer, Hannes; Dietrich, Peter

    2016-04-01

    Ecosystems are often characterized by their high heterogeneity, complexity and dynamic. Hence, single point measurements are often not sufficient for their complete representation. The application of wireless sensor networks in terrestrial and aquatic environmental systems offer significant benefits as a better consideration to the local test conditions, due to the simple adjustment of the sensor distribution, the sensor types and the sample rate. Another advantage of wireless ad-hoc sensor networks is their self-organizing behavior, resulting in a major reduction in installation and operation costs and time. In addition, individual point measurements with a sensor are significantly improved by measuring at several points continuously. In this work a concept and realization for Long-term ecosystem research is given in the field monitoring of micrometeorology and soil parameters for the interaction of biotic and abiotic processes. This long term analyses are part of the Global Change Experimental Facility (GCEF), a large field-based experimental platform to assess the effects of climate change on ecosystem functions and processes under different land-use scenarios. Regarding to the adaptive behavior of the network, also a mobile version was developed to overcome the lack of information of temporally and spatially fixed measurements for the detection and recording of highly dynamic or time limited processes. First results of different field campaigns are given to present the potentials and limitations of this application in environmental science, especially for the monitoring of the interaction of biotic and abiotic processes, soil-atmosphere interaction and the validation of remote sensing data.

  14. SARA: a self-adaptive and resource-aware approach towards secure wireless ad hoc and sensor networks

    NASA Astrophysics Data System (ADS)

    Chigan, Chunxiao; Li, Leiyuan

    2005-05-01

    Providing security is essential for mission critical Wireless Ad Hoc and Sensor Networks (WAHSN) applications. Often a highly secure mechanism inevitably consumes a rather large amount of system resources, which in turn may unintentionally cause a Security Service Denial of Service (SSDoS) attack. This paper proposes a self-adaptive resource-aware (SARA) security provisioning approach for WAHSNs. For resource scarce WAHSNs, SARA strives to provide the optimal tradeoff between the sufficient security (which is reflected by the Security Index (SI)) and the acceptable network performance degradation (which is reflected by the Performance Index (PI)). With the support of the offline optimal secure protocol selection module and the online self-adaptive security control module, SARA is capable of employing different combinations of secure protocol sets to satisfy different security need at different condition for different applications. To determine the security index SI of a secure protocol set, a heuristic cross-layer security-service mapping mechanism is presented. Furthermore, we evaluate performance index PI of a secure protocol set via simulation followed by Analysis of Variance (ANOVA). Consequently, the proposed self-adaptive security provisioning based on both SI and PI achieves the maximum overall network security services and network performance services, without causing the SSDoS attack. Furthermore, this self-adaptive mechanism is capable of switching from one secure protocol set to another while keeping similar level of security and performance, it thus provides additional security by security service hopping.

  15. FPGA-based slope computation for ELTs adaptive optics wavefront sensors

    NASA Astrophysics Data System (ADS)

    Rodríguez Ramos, L. F.; Díaz Garcia, J. J.; Piqueras Meseguer, J. J.; Martin Hernando, Y.; Rodríguez Ramos, J. M.

    2008-07-01

    ELTs laser guide stars wavefront sensors are planned to have specifically developed sensor chips, which will probably include readout logic and D/A conversion, followed by a powerful FPGA slope computer located very close to it, but not inside for flexibility and simplicity reasons. This paper presents the architecture of an FPGA-based wavefront slope computer, capable of handling the sensor output stream in a massively parallel approach. It will feature the ability of performing dark and flat field correction, the flexibility needed for allocating complex processing schemes, the capability of undertaking all computations expected to be performed at maximum speed, even though they were not strictly related to the calculation of the slopes, and the necessary housekeeping controls to properly command it and evaluate its behaviour. Feasibility using today's technology is evaluated, clearly showing its viability, together with an analysis of the amount of external memory, power consumption and printed circuit board space needed.

  16. Integrated sensor with frame memory and programmable resolution for light adaptive imaging

    NASA Technical Reports Server (NTRS)

    Zhou, Zhimin (Inventor); Fossum, Eric R. (Inventor); Pain, Bedabrata (Inventor)

    2004-01-01

    An image sensor operable to vary the output spatial resolution according to a received light level while maintaining a desired signal-to-noise ratio. Signals from neighboring pixels in a pixel patch with an adjustable size are added to increase both the image brightness and signal-to-noise ratio. One embodiment comprises a sensor array for receiving input signals, a frame memory array for temporarily storing a full frame, and an array of self-calibration column integrators for uniform column-parallel signal summation. The column integrators are capable of substantially canceling fixed pattern noise.

  17. Adapt

    NASA Astrophysics Data System (ADS)

    Bargatze, L. F.

    2015-12-01

    Active Data Archive Product Tracking (ADAPT) is a collection of software routines that permits one to generate XML metadata files to describe and register data products in support of the NASA Heliophysics Virtual Observatory VxO effort. ADAPT is also a philosophy. The ADAPT concept is to use any and all available metadata associated with scientific data to produce XML metadata descriptions in a consistent, uniform, and organized fashion to provide blanket access to the full complement of data stored on a targeted data server. In this poster, we present an application of ADAPT to describe all of the data products that are stored by using the Common Data File (CDF) format served out by the CDAWEB and SPDF data servers hosted at the NASA Goddard Space Flight Center. These data servers are the primary repositories for NASA Heliophysics data. For this purpose, the ADAPT routines have been used to generate data resource descriptions by using an XML schema named Space Physics Archive, Search, and Extract (SPASE). SPASE is the designated standard for documenting Heliophysics data products, as adopted by the Heliophysics Data and Model Consortium. The set of SPASE XML resource descriptions produced by ADAPT includes high-level descriptions of numerical data products, display data products, or catalogs and also includes low-level "Granule" descriptions. A SPASE Granule is effectively a universal access metadata resource; a Granule associates an individual data file (e.g. a CDF file) with a "parent" high-level data resource description, assigns a resource identifier to the file, and lists the corresponding assess URL(s). The CDAWEB and SPDF file systems were queried to provide the input required by the ADAPT software to create an initial set of SPASE metadata resource descriptions. Then, the CDAWEB and SPDF data repositories were queried subsequently on a nightly basis and the CDF file lists were checked for any changes such as the occurrence of new, modified, or deleted

  18. A near-infrared tip-tilt sensor for the Keck I laser guide star adaptive optics system

    NASA Astrophysics Data System (ADS)

    Wizinowich, Peter; Smith, Roger; Biasi, Roberto; Cetre, Sylvain; Dekany, Richard; Femenia-Castella, Bruno; Fucik, Jason; Hale, David; Neyman, Chris; Pescoller, Dietrich; Ragland, Sam; Stomski, Paul; Andrighettoni, Mario; Bartos, Randy; Bui, Khanh; Cooper, Andrew; Cromer, John; van Dam, Marcos; Hess, Michael; James, Ean; Lyke, Jim; Rodriguez, Hector; Stalcup, Thomas

    2014-07-01

    The sky coverage and performance of laser guide star (LGS) adaptive optics (AO) systems is limited by the natural guide star (NGS) used for low order correction. This limitation can be dramatically reduced by measuring the tip and tilt of the NGS in the near-infrared where the NGS is partially corrected by the LGS AO system and where stars are generally several magnitudes brighter than at visible wavelengths. We present the design of a near-infrared tip-tilt sensor that has recently been integrated with the Keck I telescope's LGS AO system along with some initial on-sky results. The implementation involved modifications to the AO bench, real-time control system, and higher level controls and operations software that will also be discussed. The tip-tilt sensor is a H2RG-based near-infrared camera with 0.05 arc second pixels. Low noise at high sample rates is achieved by only reading a small region of interest, from 2×2 to 16×16 pixels, centered on an NGS anywhere in the 100 arc second diameter field. The sensor operates at either Ks or H-band using light reflected by a choice of dichroic beamsplitters located in front of the OSIRIS integral field spectrograph.

  19. Use of the LIGA process for the production of pyramid wavefront sensors for adaptive optics in astronomy

    NASA Astrophysics Data System (ADS)

    Ghigo, Mauro; Diolaiti, Emiliano; Perennes, Frederic; Ragazzoni, Roberto

    2003-12-01

    Nowadays many groups in the world are developing adaptive optics (AO) systems for the real time correction of the aberrations introduced by the turbolence of the atmosphere in the field of view of the astronomical telescopes. The Shack-Hartmann wavefront sensor has been often used for the detection of the optical aberrations but over the past few years an alternative wavefront sensor with pyramidic shape has being developed. The properties of this sensor have been extensively investigated both theoretically and experimentally (for example in the AO module of the Italian "Telescopio Nazionale Galileo"). Important features of this pyramidal sensor are that it offers the advantage of either variable gain against the wavefront deformation and tunable sampling of the telescope pupil. These features translate into a considerable gain in the limiting magnitude of the reference star when compared to the classical Shack-Hartmann sensor. The manufacturing of single pyramid prototypes has been initially accomplished using the classical figuring and polishing technique, a time consuming procedure. Since the multi-conjugated adaptive optics (MCAO) that are under study, foresee the use of a large number of identical pyramids, it has been investigated and developed an alternative method for the mass production of this optical component. Using a lithography-dedicated beamline already operating at the ELETTRA Synchrotron in Trieste, a manufacturing technique has been implemented that uses a process named LIGA [Lithography, electroplating (German: Galvanik) and molding (German: Abformung)]. With this method is it possible to create a master pyramid made of a polymeric material and having the characteristics requested. The master is then used to create a metallic mold by means of electroforming. In the end the mold is used for the molding of a number of identical pyramids made in a suitable amorphous optical polymer, using the technique of the hot embossing. This technique produce

  20. CPAC: Energy-Efficient Data Collection through Adaptive Selection of Compression Algorithms for Sensor Networks

    PubMed Central

    Lee, HyungJune; Kim, HyunSeok; Chang, Ik Joon

    2014-01-01

    We propose a technique to optimize the energy efficiency of data collection in sensor networks by exploiting a selective data compression. To achieve such an aim, we need to make optimal decisions regarding two aspects: (1) which sensor nodes should execute compression; and (2) which compression algorithm should be used by the selected sensor nodes. We formulate this problem into binary integer programs, which provide an energy-optimal solution under the given latency constraint. Our simulation results show that the optimization algorithm significantly reduces the overall network-wide energy consumption for data collection. In the environment having a stationary sink from stationary sensor nodes, the optimized data collection shows 47% energy savings compared to the state-of-the-art collection protocol (CTP). More importantly, we demonstrate that our optimized data collection provides the best performance in an intermittent network under high interference. In such networks, we found that the selective compression for frequent packet retransmissions saves up to 55% energy compared to the best known protocol. PMID:24721763

  1. 40 CFR 610.32 - Test fleet selection.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 29 2010-07-01 2010-07-01 false Test fleet selection. 610.32 Section... fleet selection. (a) The composition and size of the test fleet will be determined by the Administrator... test fleet will be determined by the Administrator in consultation with the FTC. (b) The goal of...

  2. A sun-crown-sensor model and adapted C-correction logic for topographic correction of high resolution forest imagery

    NASA Astrophysics Data System (ADS)

    Fan, Yuanchao; Koukal, Tatjana; Weisberg, Peter J.

    2014-10-01

    Canopy shadowing mediated by topography is an important source of radiometric distortion on remote sensing images of rugged terrain. Topographic correction based on the sun-canopy-sensor (SCS) model significantly improved over those based on the sun-terrain-sensor (STS) model for surfaces with high forest canopy cover, because the SCS model considers and preserves the geotropic nature of trees. The SCS model accounts for sub-pixel canopy shadowing effects and normalizes the sunlit canopy area within a pixel. However, it does not account for mutual shadowing between neighboring pixels. Pixel-to-pixel shadowing is especially apparent for fine resolution satellite images in which individual tree crowns are resolved. This paper proposes a new topographic correction model: the sun-crown-sensor (SCnS) model based on high-resolution satellite imagery (IKONOS) and high-precision LiDAR digital elevation model. An improvement on the C-correction logic with a radiance partitioning method to address the effects of diffuse irradiance is also introduced (SCnS + C). In addition, we incorporate a weighting variable, based on pixel shadow fraction, on the direct and diffuse radiance portions to enhance the retrieval of at-sensor radiance and reflectance of highly shadowed tree pixels and form another variety of SCnS model (SCnS + W). Model evaluation with IKONOS test data showed that the new SCnS model outperformed the STS and SCS models in quantifying the correlation between terrain-regulated illumination factor and at-sensor radiance. Our adapted C-correction logic based on the sun-crown-sensor geometry and radiance partitioning better represented the general additive effects of diffuse radiation than C parameters derived from the STS or SCS models. The weighting factor Wt also significantly enhanced correction results by reducing within-class standard deviation and balancing the mean pixel radiance between sunlit and shaded slopes. We analyzed these improvements with model

  3. Adaptive switching filter for noise removal in highly corrupted depth maps from Time-of-Flight image sensors

    NASA Astrophysics Data System (ADS)

    Lee, Seunghee; Bae, Kwanghyuk; Kyung, Kyu-min; Kim, Tae-Chan

    2012-03-01

    In this work, we present an adaptive switching filter for noise reduction and sharpness preservation in depth maps provided by Time-of-Flight (ToF) image sensors. Median filter and bilateral filter are commonly used in cost-sensitive applications where low computational complexity is needed. However, median filter blurs fine details and edges in depth map while bilateral filter works poorly with impulse noise present in the image. Since the variance of depth is inversely proportional to amplitude, we suggest an adaptive filter that switches between median filter and bilateral filter based on the level of amplitude. If a region of interest has low amplitude indicating low confidence level of measured depth data, then median filter is applied on the depth at the position while regions with high level of amplitude is processed with bilateral filter using Gaussian kernel with adaptive weights. Results show that the suggested algorithm performs surface smoothing and detail preservation as well as median filter and bilateral filter, respectively. By using the suggested algorithm, significant gain in visual quality is obtained in depth maps while low computational cost is maintained.

  4. A Real-Time Capable Software-Defined Receiver Using GPU for Adaptive Anti-Jam GPS Sensors

    PubMed Central

    Seo, Jiwon; Chen, Yu-Hsuan; De Lorenzo, David S.; Lo, Sherman; Enge, Per; Akos, Dennis; Lee, Jiyun

    2011-01-01

    Due to their weak received signal power, Global Positioning System (GPS) signals are vulnerable to radio frequency interference. Adaptive beam and null steering of the gain pattern of a GPS antenna array can significantly increase the resistance of GPS sensors to signal interference and jamming. Since adaptive array processing requires intensive computational power, beamsteering GPS receivers were usually implemented using hardware such as field-programmable gate arrays (FPGAs). However, a software implementation using general-purpose processors is much more desirable because of its flexibility and cost effectiveness. This paper presents a GPS software-defined radio (SDR) with adaptive beamsteering capability for anti-jam applications. The GPS SDR design is based on an optimized desktop parallel processing architecture using a quad-core Central Processing Unit (CPU) coupled with a new generation Graphics Processing Unit (GPU) having massively parallel processors. This GPS SDR demonstrates sufficient computational capability to support a four-element antenna array and future GPS L5 signal processing in real time. After providing the details of our design and optimization schemes for future GPU-based GPS SDR developments, the jamming resistance of our GPS SDR under synthetic wideband jamming is presented. Since the GPS SDR uses commercial-off-the-shelf hardware and processors, it can be easily adopted in civil GPS applications requiring anti-jam capabilities. PMID:22164116

  5. 2012 Earth-Orbiting Heliophysics Fleet

    NASA Video Gallery

    Since Sentinels of the Heliosphere in 2008, there have been a few new missions, and a few missions have been shut down. As of Fall of 2012, here's a tour of the NASA Near-Earth Heliophysics fleet, ...

  6. Adaptive Control of the Packet Transmission Period with Solar Energy Harvesting Prediction in Wireless Sensor Networks

    PubMed Central

    Kwon, Kideok; Yang, Jihoon; Yoo, Younghwan

    2015-01-01

    A number of research works has studied packet scheduling policies in energy scavenging wireless sensor networks, based on the predicted amount of harvested energy. Most of them aim to achieve energy neutrality, which means that an embedded system can operate perpetually while meeting application requirements. Unlike other renewable energy sources, solar energy has the feature of distinct periodicity in the amount of harvested energy over a day. Using this feature, this paper proposes a packet transmission control policy that can enhance the network performance while keeping sensor nodes alive. Furthermore, this paper suggests a novel solar energy prediction method that exploits the relation between cloudiness and solar radiation. The experimental results and analyses show that the proposed packet transmission policy outperforms others in terms of the deadline miss rate and data throughput. Furthermore, the proposed solar energy prediction method can predict more accurately than others by 6.92%. PMID:25919372

  7. Adaptive control of the packet transmission period with solar energy harvesting prediction in wireless sensor networks.

    PubMed

    Kwon, Kideok; Yang, Jihoon; Yoo, Younghwan

    2015-01-01

    A number of research works has studied packet scheduling policies in energy scavenging wireless sensor networks, based on the predicted amount of harvested energy. Most of them aim to achieve energy neutrality, which means that an embedded system can operate perpetually while meeting application requirements. Unlike other renewable energy sources, solar energy has the feature of distinct periodicity in the amount of harvested energy over a day. Using this feature, this paper proposes a packet transmission control policy that can enhance the network performance while keeping sensor nodes alive. Furthermore, this paper suggests a novel solar energy prediction method that exploits the relation between cloudiness and solar radiation. The experimental results and analyses show that the proposed packet transmission policy outperforms others in terms of the deadline miss rate and data throughput. Furthermore, the proposed solar energy prediction method can predict more accurately than others by 6.92%. PMID:25919372

  8. The Consolidated Fleet XN2Y-1

    NASA Technical Reports Server (NTRS)

    1935-01-01

    The Consolidated Fleet XN2Y-1 was a Fleet 1 trainer purchased by the Navy for evaluation. The purchase of several N2Y-1 aircraft followed, for use as trainers for the pilots who would fly the 'parasite' fighters attached to the airships Akron and Macon. The XN2Y-1 was turned over to the NACA for research work. Note the that vertical surfaces are instrumented for NACA spin work.

  9. Consolidated Fleet N2Y-1

    NASA Technical Reports Server (NTRS)

    1930-01-01

    Consolidated Fleet N2Y-1: The Consolidated Fleet N2Y-1 aircraft were used as trainers for the pilots who would fly the 'parasite' fighters attached to the airships Akron and Macon. This N2Y-1 was turned over to the NACA for research work. Note that the vertical surfaces are instrumented for NACA work. This N2Y was used for landing gear tests.

  10. Adapting physically complete models to vehicle-based EMI array sensor data: data inversion and discrimination studies

    NASA Astrophysics Data System (ADS)

    Shubitidze, Fridon; Miller, Jonathan S.; Schultz, Gregory M.; Marble, Jay A.

    2010-04-01

    This paper reports vehicle based electromagnetic induction (EMI) array sensor data inversion and discrimination results. Recent field studies show that EMI arrays, such as the Minelab Single Transmitter Multiple Receiver (STMR), and the Geophex GEM-5 EMI array, provide a fast and safe way to detect subsurface metallic targets such as landmines, unexploded ordnance (UXO) and buried explosives. The array sensors are flexible and easily adaptable for a variety of ground vehicles and mobile platforms, which makes them very attractive for safe and cost effective detection operations in many applications, including but not limited to explosive ordnance disposal and humanitarian UXO and demining missions. Most state-of-the-art EMI arrays measure the vertical or full vector field, or gradient tensor fields and utilize them for real-time threat detection based on threshold analysis. Real field practice shows that the threshold-level detection has high false alarms. One way to reduce these false alarms is to use EMI numerical techniques that are capable of inverting EMI array data in real time. In this work a physically complete model, known as the normalized volume/surface magnetic sources (NV/SMS) model is adapted to the vehicle-based EMI array, such as STMR and GEM-5, data. The NV/SMS model can be considered as a generalized volume or surface dipole model, which in a special limited case coincides with an infinitesimal dipole model approach. According to the NV/SMS model, an object's response to a sensor's primary field is modeled mathematically by a set of equivalent magnetic dipoles, distributed inside the object (i.e. NVMS) or over a surface surrounding the object (i.e. NSMS). The scattered magnetic field of the NSMS is identical to that produced by a set of interacting magnetic dipoles. The amplitudes of the magnetic dipoles are normalized to the primary magnetic field, relating induced magnetic dipole polarizability and the primary magnetic field. The magnitudes of

  11. The CAFADIS camera: a new tomographic wavefront sensor for Adaptive Optics

    NASA Astrophysics Data System (ADS)

    Rodríguez, J. M.; Femenía, B.; Montilla, I.; Rodríguez-Ramos, L. F.; Marichal-Hernández, J. G.; Lüke, J. P.; López, R.; Díaz, J. J.; Martín, Y.

    The CAFADIS camera is a new wavefront sensor (WFS) patented by the Universidad de La Laguna. CAFADIS is a system based on the concept of plenoptic camera originally proposed by Adelson and Wang [Single lens stereo with a plenoptic camera, IEEE Transactions on Pattern Analysis and Machine Intelligence 14 (1992)] and its most salient feature is its ability to simultaneously measuring wavefront maps and distances to objects [Wavefront and distance measurements using the CAFADIS camera, in Astronomical telescopes, Marseille (2008)]. This makes of CAFADIS an interesting alternative for LGS-based AO systems as it is capable of measuring from an LGS-beacon the atmospheric turbulence wavefront and simultaneously the distance to the LGS beacon thus removing the need of a NGS defocus sensor to probe changes in distance to the LGS beacon due to drifts of the mesospheric Na layer. In principle, the concept can also be employed to recover 3D profiles of the Na Layer allowing for optimizations of the measurement of the distance to the LGS-beacon. Currently we are investigating the possibility of extending the plenoptic WFS into a tomographic wavefront sensor. Simulations will be shown of a plenoptic WFS when operated within an LGS-based AO system for the recovery of wavefront maps at different heights. The preliminary results presented here show the tomographic ability of CAFADIS.

  12. Virtual Wireless Sensor Networks: Adaptive Brain-Inspired Configuration for Internet of Things Applications.

    PubMed

    Toyonaga, Shinya; Kominami, Daichi; Murata, Masayuki

    2016-01-01

    Many researchers are devoting attention to the so-called "Internet of Things" (IoT), and wireless sensor networks (WSNs) are regarded as a critical technology for realizing the communication infrastructure of the future, including the IoT. Against this background, virtualization is a crucial technique for the integration of multiple WSNs. Designing virtualized WSNs for actual environments will require further detailed studies. Within the IoT environment, physical networks can undergo dynamic change, and so, many problems exist that could prevent applications from running without interruption when using the existing approaches. In this paper, we show an overall architecture that is suitable for constructing and running virtual wireless sensor network (VWSN) services within a VWSN topology. Our approach provides users with a reliable VWSN network by assigning redundant resources according to each user's demand and providing a recovery method to incorporate environmental changes. We tested this approach by simulation experiment, with the results showing that the VWSN network is reliable in many cases, although physical deployment of sensor nodes and the modular structure of the VWSN will be quite important to the stability of services within the VWSN topology. PMID:27548177

  13. ADAPTIVE WATER SENSOR SIGNAL PROCESSING: EXPERIMENTAL RESULTS AND IMPLICATIONS FOR ONLINE CONTAMINANT WARNING SYSTEMS

    EPA Science Inventory

    A contaminant detection technique and its optimization algorithms have two principal functions. One is the adaptive signal treatment that suppresses background noise and enhances contaminant signals, leading to a promising detection of water quality changes at a false rate as low...

  14. Dynamic experiment design regularization approach to adaptive imaging with array radar/SAR sensor systems.

    PubMed

    Shkvarko, Yuriy; Tuxpan, José; Santos, Stewart

    2011-01-01

    We consider a problem of high-resolution array radar/SAR imaging formalized in terms of a nonlinear ill-posed inverse problem of nonparametric estimation of the power spatial spectrum pattern (SSP) of the random wavefield scattered from a remotely sensed scene observed through a kernel signal formation operator and contaminated with random Gaussian noise. First, the Sobolev-type solution space is constructed to specify the class of consistent kernel SSP estimators with the reproducing kernel structures adapted to the metrics in such the solution space. Next, the "model-free" variational analysis (VA)-based image enhancement approach and the "model-based" descriptive experiment design (DEED) regularization paradigm are unified into a new dynamic experiment design (DYED) regularization framework. Application of the proposed DYED framework to the adaptive array radar/SAR imaging problem leads to a class of two-level (DEED-VA) regularized SSP reconstruction techniques that aggregate the kernel adaptive anisotropic windowing with the projections onto convex sets to enforce the consistency and robustness of the overall iterative SSP estimators. We also show how the proposed DYED regularization method may be considered as a generalization of the MVDR, APES and other high-resolution nonparametric adaptive radar sensing techniques. A family of the DYED-related algorithms is constructed and their effectiveness is finally illustrated via numerical simulations. PMID:22163859

  15. An experimental infrared sensor using adaptive coded apertures for enhanced resolution

    NASA Astrophysics Data System (ADS)

    Gordon, Neil T.; de Villiers, Geoffrey D.; Ridley, Kevin D.; Bennett, Charlotte R.; McNie, Mark E.; Proudler, Ian K.; Russell, Lee; Slinger, Christopher W.; Gilholm, Kevin

    2010-08-01

    Adaptive coded aperture imaging (ACAI) has the potential to enhance greatly the performance of sensing systems by allowing sub detector pixel image and tracking resolution. A small experimental system has been set up to allow the practical demonstration of these benefits in the mid infrared, as well as investigating the calibration and stability of the system. The system can also be used to test modeling of similar ACAI systems in the infrared. The demonstrator can use either a set of fixed masks or a novel MOEMS adaptive transmissive spatial light modulator. This paper discusses the design and testing of the system including the development of novel decoding algorithms and some initial imaging results are presented.

  16. An energy-efficient rate adaptive media access protocol (RA-MAC) for long-lived sensor networks.

    PubMed

    Hu, Wen; Chen, Quanjun; Corke, Peter; O'Rourke, Damien

    2010-01-01

    We introduce an energy-efficient Rate Adaptive Media Access Control (RA-MAC) algorithm for long-lived Wireless Sensor Networks (WSNs). Previous research shows that the dynamic and lossy nature of wireless communications is one of the major challenges to reliable data delivery in WSNs. RA-MAC achieves high link reliability in such situations by dynamically trading off data rate for channel gain. The extra gain that can be achieved reduces the packet loss rate which contributes to reduced energy expenditure through a reduced numbers of retransmissions. We achieve this at the expense of raw bit rate which generally far exceeds the application's link requirement. To minimize communication energy consumption, RA-MAC selects the optimal data rate based on the estimated link quality at each data rate and an analytical model of the energy consumption. Our model shows how the selected data rate depends on different channel conditions in order to minimize energy consumption. We have implemented RA-MAC in TinyOS for an off-the-shelf sensor platform (the TinyNode) on top of a state-of-the-art WSN Media Access Control Protocol, SCP-MAC, and evaluated its performance by comparing our implementation with the original SCP-MAC using both simulation and experiment. PMID:22219675

  17. A New Model Based on Adaptation of the External Loop to Compensate the Hysteresis of Tactile Sensors

    PubMed Central

    Sánchez-Durán, José A.; Vidal-Verdú, Fernando; Oballe-Peinado, Óscar; Castellanos-Ramos, Julián; Hidalgo-López, José A.

    2015-01-01

    This paper presents a novel method to compensate for hysteresis nonlinearities observed in the response of a tactile sensor. The External Loop Adaptation Method (ELAM) performs a piecewise linear mapping of the experimentally measured external curves of the hysteresis loop to obtain all possible internal cycles. The optimal division of the input interval where the curve is approximated is provided by the error minimization algorithm. This process is carried out off line and provides parameters to compute the split point in real time. A different linear transformation is then performed at the left and right of this point and a more precise fitting is achieved. The models obtained with the ELAM method are compared with those obtained from three other approaches. The results show that the ELAM method achieves a more accurate fitting. Moreover, the involved mathematical operations are simpler and therefore easier to implement in devices such as Field Programmable Gate Array (FPGAs) for real time applications. Furthermore, the method needs to identify fewer parameters and requires no previous selection process of operators or functions. Finally, the method can be applied to other sensors or actuators with complex hysteresis loop shapes. PMID:26501279

  18. Visualization of Time-Series Sensor Data to Inform the Design of Just-In-Time Adaptive Stress Interventions

    PubMed Central

    Sharmin, Moushumi; Raij, Andrew; Epstien, David; Nahum-Shani, Inbal; Beck, J. Gayle; Vhaduri, Sudip; Preston, Kenzie; Kumar, Santosh

    2015-01-01

    We investigate needs, challenges, and opportunities in visualizing time-series sensor data on stress to inform the design of just-in-time adaptive interventions (JITAIs). We identify seven key challenges: massive volume and variety of data, complexity in identifying stressors, scalability of space, multifaceted relationship between stress and time, a need for representation at multiple granularities, interperson variability, and limited understanding of JITAI design requirements due to its novelty. We propose four new visualizations based on one million minutes of sensor data (n=70). We evaluate our visualizations with stress researchers (n=6) to gain first insights into its usability and usefulness in JITAI design. Our results indicate that spatio-temporal visualizations help identify and explain between- and within-person variability in stress patterns and contextual visualizations enable decisions regarding the timing, content, and modality of intervention. Interestingly, a granular representation is considered informative but noise-prone; an abstract representation is the preferred starting point for designing JITAIs. PMID:26539566

  19. An Energy-efficient Rate Adaptive Media Access Protocol (RA-MAC) for Long-lived Sensor Networks

    PubMed Central

    Hu, Wen; Chen, Quanjun; Corke, Peter; O’Rourke, Damien

    2010-01-01

    We introduce an energy-efficient Rate Adaptive Media Access Control (RA-MAC) algorithm for long-lived Wireless Sensor Networks (WSNs). Previous research shows that the dynamic and lossy nature of wireless communications is one of the major challenges to reliable data delivery in WSNs. RA-MAC achieves high link reliability in such situations by dynamically trading off data rate for channel gain. The extra gain that can be achieved reduces the packet loss rate which contributes to reduced energy expenditure through a reduced numbers of retransmissions. We achieve this at the expense of raw bit rate which generally far exceeds the application’s link requirement. To minimize communication energy consumption, RA-MAC selects the optimal data rate based on the estimated link quality at each data rate and an analytical model of the energy consumption. Our model shows how the selected data rate depends on different channel conditions in order to minimize energy consumption. We have implemented RA-MAC in TinyOS for an off-the-shelf sensor platform (the TinyNode) on top of a state-of-the-art WSN Media Access Control Protocol, SCP-MAC, and evaluated its performance by comparing our implementation with the original SCP-MAC using both simulation and experiment. PMID:22219675

  20. A new model based on adaptation of the external loop to compensate the hysteresis of tactile sensors.

    PubMed

    Sánchez-Durán, José A; Vidal-Verdú, Fernando; Oballe-Peinado, Óscar; Castellanos-Ramos, Julián; Hidalgo-López, José A

    2015-01-01

    This paper presents a novel method to compensate for hysteresis nonlinearities observed in the response of a tactile sensor. The External Loop Adaptation Method (ELAM) performs a piecewise linear mapping of the experimentally measured external curves of the hysteresis loop to obtain all possible internal cycles. The optimal division of the input interval where the curve is approximated is provided by the error minimization algorithm. This process is carried out off line and provides parameters to compute the split point in real time. A different linear transformation is then performed at the left and right of this point and a more precise fitting is achieved. The models obtained with the ELAM method are compared with those obtained from three other approaches. The results show that the ELAM method achieves a more accurate fitting. Moreover, the involved mathematical operations are simpler and therefore easier to implement in devices such as Field Programmable Gate Array (FPGAs) for real time applications. Furthermore, the method needs to identify fewer parameters and requires no previous selection process of operators or functions. Finally, the method can be applied to other sensors or actuators with complex hysteresis loop shapes. PMID:26501279

  1. An adaptive OFDMA-based MAC protocol for underwater acoustic wireless sensor networks.

    PubMed

    Khalil, Issa M; Gadallah, Yasser; Hayajneh, Mohammad; Khreishah, Abdallah

    2012-01-01

    Underwater acoustic wireless sensor networks (UAWSNs) have many applications across various civilian and military domains. However, they suffer from the limited available bandwidth of acoustic signals and harsh underwater conditions. In this work, we present an Orthogonal Frequency Division Multiple Access (OFDMA)-based Media Access Control (MAC) protocol that is configurable to suit the operating requirements of the underwater sensor network. The protocol has three modes of operation, namely random, equal opportunity and energy-conscious modes of operation. Our MAC design approach exploits the multi-path characteristics of a fading acoustic channel to convert it into parallel independent acoustic sub-channels that undergo flat fading. Communication between node pairs within the network is done using subsets of these sub-channels, depending on the configurations of the active mode of operation. Thus, the available limited bandwidth gets fully utilized while completely avoiding interference. We derive the mathematical model for optimal power loading and subcarrier selection, which is used as basis for all modes of operation of the protocol. We also conduct many simulation experiments to evaluate and compare our protocol with other Code Division Multiple Access (CDMA)-based MAC protocols. PMID:23012517

  2. An Adaptive OFDMA-Based MAC Protocol for Underwater Acoustic Wireless Sensor Networks

    PubMed Central

    Khalil, Issa M.; Gadallah, Yasser; Hayajneh, Mohammad; Khreishah, Abdallah

    2012-01-01

    Underwater acoustic wireless sensor networks (UAWSNs) have many applications across various civilian and military domains. However, they suffer from the limited available bandwidth of acoustic signals and harsh underwater conditions. In this work, we present an Orthogonal Frequency Division Multiple Access (OFDMA)-based Media Access Control (MAC) protocol that is configurable to suit the operating requirements of the underwater sensor network. The protocol has three modes of operation, namely random, equal opportunity and energy-conscious modes of operation. Our MAC design approach exploits the multi-path characteristics of a fading acoustic channel to convert it into parallel independent acoustic sub-channels that undergo flat fading. Communication between node pairs within the network is done using subsets of these sub-channels, depending on the configurations of the active mode of operation. Thus, the available limited bandwidth gets fully utilized while completely avoiding interference. We derive the mathematical model for optimal power loading and subcarrier selection, which is used as basis for all modes of operation of the protocol. We also conduct many simulation experiments to evaluate and compare our protocol with other Code Division Multiple Access (CDMA)-based MAC protocols. PMID:23012517

  3. New Trends in Robotics for Agriculture: Integration and Assessment of a Real Fleet of Robots

    PubMed Central

    Gonzalez-de-Soto, Mariano; Pajares, Gonzalo

    2014-01-01

    Computer-based sensors and actuators such as global positioning systems, machine vision, and laser-based sensors have progressively been incorporated into mobile robots with the aim of configuring autonomous systems capable of shifting operator activities in agricultural tasks. However, the incorporation of many electronic systems into a robot impairs its reliability and increases its cost. Hardware minimization, as well as software minimization and ease of integration, is essential to obtain feasible robotic systems. A step forward in the application of automatic equipment in agriculture is the use of fleets of robots, in which a number of specialized robots collaborate to accomplish one or several agricultural tasks. This paper strives to develop a system architecture for both individual robots and robots working in fleets to improve reliability, decrease complexity and costs, and permit the integration of software from different developers. Several solutions are studied, from a fully distributed to a whole integrated architecture in which a central computer runs all processes. This work also studies diverse topologies for controlling fleets of robots and advances other prospective topologies. The architecture presented in this paper is being successfully applied in the RHEA fleet, which comprises three ground mobile units based on a commercial tractor chassis. PMID:25143976

  4. New trends in robotics for agriculture: integration and assessment of a real fleet of robots.

    PubMed

    Emmi, Luis; Gonzalez-de-Soto, Mariano; Pajares, Gonzalo; Gonzalez-de-Santos, Pablo

    2014-01-01

    Computer-based sensors and actuators such as global positioning systems, machine vision, and laser-based sensors have progressively been incorporated into mobile robots with the aim of configuring autonomous systems capable of shifting operator activities in agricultural tasks. However, the incorporation of many electronic systems into a robot impairs its reliability and increases its cost. Hardware minimization, as well as software minimization and ease of integration, is essential to obtain feasible robotic systems. A step forward in the application of automatic equipment in agriculture is the use of fleets of robots, in which a number of specialized robots collaborate to accomplish one or several agricultural tasks. This paper strives to develop a system architecture for both individual robots and robots working in fleets to improve reliability, decrease complexity and costs, and permit the integration of software from different developers. Several solutions are studied, from a fully distributed to a whole integrated architecture in which a central computer runs all processes. This work also studies diverse topologies for controlling fleets of robots and advances other prospective topologies. The architecture presented in this paper is being successfully applied in the RHEA fleet, which comprises three ground mobile units based on a commercial tractor chassis. PMID:25143976

  5. An Adaptive Data Gathering Scheme for Multi-Hop Wireless Sensor Networks Based on Compressed Sensing and Network Coding.

    PubMed

    Yin, Jun; Yang, Yuwang; Wang, Lei

    2016-01-01

    Joint design of compressed sensing (CS) and network coding (NC) has been demonstrated to provide a new data gathering paradigm for multi-hop wireless sensor networks (WSNs). By exploiting the correlation of the network sensed data, a variety of data gathering schemes based on NC and CS (Compressed Data Gathering-CDG) have been proposed. However, these schemes assume that the sparsity of the network sensed data is constant and the value of the sparsity is known before starting each data gathering epoch, thus they ignore the variation of the data observed by the WSNs which are deployed in practical circumstances. In this paper, we present a complete design of the feedback CDG scheme where the sink node adaptively queries those interested nodes to acquire an appropriate number of measurements. The adaptive measurement-formation procedure and its termination rules are proposed and analyzed in detail. Moreover, in order to minimize the number of overall transmissions in the formation procedure of each measurement, we have developed a NP-complete model (Maximum Leaf Nodes Minimum Steiner Nodes-MLMS) and realized a scalable greedy algorithm to solve the problem. Experimental results show that the proposed measurement-formation method outperforms previous schemes, and experiments on both datasets from ocean temperature and practical network deployment also prove the effectiveness of our proposed feedback CDG scheme. PMID:27043574

  6. An Adaptive Data Gathering Scheme for Multi-Hop Wireless Sensor Networks Based on Compressed Sensing and Network Coding

    PubMed Central

    Yin, Jun; Yang, Yuwang; Wang, Lei

    2016-01-01

    Joint design of compressed sensing (CS) and network coding (NC) has been demonstrated to provide a new data gathering paradigm for multi-hop wireless sensor networks (WSNs). By exploiting the correlation of the network sensed data, a variety of data gathering schemes based on NC and CS (Compressed Data Gathering—CDG) have been proposed. However, these schemes assume that the sparsity of the network sensed data is constant and the value of the sparsity is known before starting each data gathering epoch, thus they ignore the variation of the data observed by the WSNs which are deployed in practical circumstances. In this paper, we present a complete design of the feedback CDG scheme where the sink node adaptively queries those interested nodes to acquire an appropriate number of measurements. The adaptive measurement-formation procedure and its termination rules are proposed and analyzed in detail. Moreover, in order to minimize the number of overall transmissions in the formation procedure of each measurement, we have developed a NP-complete model (Maximum Leaf Nodes Minimum Steiner Nodes—MLMS) and realized a scalable greedy algorithm to solve the problem. Experimental results show that the proposed measurement-formation method outperforms previous schemes, and experiments on both datasets from ocean temperature and practical network deployment also prove the effectiveness of our proposed feedback CDG scheme. PMID:27043574

  7. A fiber optic sensor system for control of rate-adaptive cardiac pacemakers and implantable defibrillators.

    PubMed

    Müller, Stefan; Hexamer, Martin; Werner, Jürgen

    2006-12-01

    Commercially available cardiac pacemakers and implantable cardioverters/defibrillators (ICDs) predominantly use an intracardiac-derived electrocardiogram (ECG) for the detection of arrhythmias. To achieve automatic control of the heart frequency in accordance with cardiovascular strain and improved detection of life-threatening arrhythmias, it is desirable to monitor the heart by an input signal correlated with the hemodynamic state. One possible approach to derive such a signal is to measure the inotropy (mechanical contraction strength of the heart muscle). For this purpose, an optoelectronic measurement system has been designed. The fundamental function of the system has been shown in earlier investigations using an isolated beating pig heart. In this paper the design of two algorithms for use in pacemakers and ICDs based on a fiber optic sensor signal is presented. PMID:17155869

  8. Filtering Based Adaptive Visual Odometry Sensor Framework Robust to Blurred Images

    PubMed Central

    Zhao, Haiying; Liu, Yong; Xie, Xiaojia; Liao, Yiyi; Liu, Xixi

    2016-01-01

    Visual odometry (VO) estimation from blurred image is a challenging problem in practical robot applications, and the blurred images will severely reduce the estimation accuracy of the VO. In this paper, we address the problem of visual odometry estimation from blurred images, and present an adaptive visual odometry estimation framework robust to blurred images. Our approach employs an objective measure of images, named small image gradient distribution (SIGD), to evaluate the blurring degree of the image, then an adaptive blurred image classification algorithm is proposed to recognize the blurred images, finally we propose an anti-blurred key-frame selection algorithm to enable the VO robust to blurred images. We also carried out varied comparable experiments to evaluate the performance of the VO algorithms with our anti-blur framework under varied blurred images, and the experimental results show that our approach can achieve superior performance comparing to the state-of-the-art methods under the condition with blurred images while not increasing too much computation cost to the original VO algorithms. PMID:27399704

  9. Filtering Based Adaptive Visual Odometry Sensor Framework Robust to Blurred Images.

    PubMed

    Zhao, Haiying; Liu, Yong; Xie, Xiaojia; Liao, Yiyi; Liu, Xixi

    2016-01-01

    Visual odometry (VO) estimation from blurred image is a challenging problem in practical robot applications, and the blurred images will severely reduce the estimation accuracy of the VO. In this paper, we address the problem of visual odometry estimation from blurred images, and present an adaptive visual odometry estimation framework robust to blurred images. Our approach employs an objective measure of images, named small image gradient distribution (SIGD), to evaluate the blurring degree of the image, then an adaptive blurred image classification algorithm is proposed to recognize the blurred images, finally we propose an anti-blurred key-frame selection algorithm to enable the VO robust to blurred images. We also carried out varied comparable experiments to evaluate the performance of the VO algorithms with our anti-blur framework under varied blurred images, and the experimental results show that our approach can achieve superior performance comparing to the state-of-the-art methods under the condition with blurred images while not increasing too much computation cost to the original VO algorithms. PMID:27399704

  10. Contributing Data to the Fleet DNA Project (Brochure)

    SciTech Connect

    Not Available

    2014-09-01

    The Fleet DNA clearinghouse of commercial fleet transportation data helps vehicle manufacturers and developers optimize vehicle designs and helps fleet managers choose advanced technologies for their fleets. This online tool - available at www.nrel.gov/fleetdna - provides data summaries and visualizations similar to real-world 'genetics' for medium- and heavy-duty commercial fleet vehicles operating within a variety of vocations. To contribute your fleet data, please contact Adam Duran of the U.S. Department of Energy's National Renewable Energy Laboratory (NREL) at adam.duran@nrel.gov or 303-275-4586.

  11. Structural adaptation of microvessel diameters in response to metabolic stimuli: where are the oxygen sensors?

    PubMed

    Reglin, Bettina; Secomb, Timothy W; Pries, Axel R

    2009-12-01

    Maintenance of functional vascular networks requires structural adaptation of vessel diameters in response to hemodynamic and metabolic conditions. The mechanisms by which diameters respond to the metabolic state are not known, but may involve the release of vasoactive substances in response to low oxygen by tissue ("tissue signaling", e.g., CO2, adenosine), by vessel walls ("wall signaling", e.g., prostaglandins, adenosine), and/or by red blood cells (RBCs) ("RBC signaling", e.g., ATP and nitric oxide). Here, the goal was to test the potential of each of these locations of oxygen-dependent signaling to control steady-state vascular diameters and tissue oxygenation. A previously developed theoretical model of structural diameter adaptation based on experimental data on microvascular network morphology and hemodynamics was used. Resulting network characteristics were analyzed with regard to tissue oxygenation (Oxdef; percentage of tissue volume with PO2<1 Torr) and the difference between estimated blood flow velocities and corresponding experimental data [velocity error (Verr); root mean square deviation of estimated vs. measured velocity]. Wall signaling led to Oxdef<1% and to the closest hemodynamic similarity (Verr: 0.60). Tissue signaling also resulted in a low oxygen deficit, but a higher Verr (0.73) and systematic diameter deviations. RBC signaling led to widespread hypoxia (Oxdef: 4.7%), unrealistic velocity distributions (Verr: 0.81), and shrinkage of small vessels. The results suggest that wall signaling plays a central role in structural control of vessel diameters in microvascular networks of given angioarchitecture. Tissue-derived and RBC-derived signaling of oxygen levels may be more relevant for the regulation of angiogenesis and/or smooth muscle tone. PMID:19783778

  12. Structural adaptation of microvessel diameters in response to metabolic stimuli: where are the oxygen sensors?

    PubMed Central

    Reglin, Bettina; Secomb, Timothy W.

    2009-01-01

    Maintenance of functional vascular networks requires structural adaptation of vessel diameters in response to hemodynamic and metabolic conditions. The mechanisms by which diameters respond to the metabolic state are not known, but may involve the release of vasoactive substances in response to low oxygen by tissue (“tissue signaling”, e.g., CO2, adenosine), by vessel walls (“wall signaling”, e.g., prostaglandins, adenosine), and/or by red blood cells (RBCs) (“RBC signaling”, e.g., ATP and nitric oxide). Here, the goal was to test the potential of each of these locations of oxygen-dependent signaling to control steady-state vascular diameters and tissue oxygenation. A previously developed theoretical model of structural diameter adaptation based on experimental data on microvascular network morphology and hemodynamics was used. Resulting network characteristics were analyzed with regard to tissue oxygenation (Oxdef; percentage of tissue volume with Po2 < 1 Torr) and the difference between estimated blood flow velocities and corresponding experimental data [velocity error (Verr); root mean square deviation of estimated vs. measured velocity]. Wall signaling led to Oxdef < 1% and to the closest hemodynamic similarity (Verr: 0.60). Tissue signaling also resulted in a low oxygen deficit, but a higher Verr (0.73) and systematic diameter deviations. RBC signaling led to widespread hypoxia (Oxdef: 4.7%), unrealistic velocity distributions (Verr: 0.81), and shrinkage of small vessels. The results suggest that wall signaling plays a central role in structural control of vessel diameters in microvascular networks of given angioarchitecture. Tissue-derived and RBC-derived signaling of oxygen levels may be more relevant for the regulation of angiogenesis and/or smooth muscle tone. PMID:19783778

  13. Fleet Tools; NREL (National Renewable Energy Laboratory)

    SciTech Connect

    2015-04-01

    From beverage distributors to shipping companies and federal agencies, industry leaders turn to the National Renewable Energy Laboratory (NREL) to help green their fleet operations. Cost, efficiency, and reliability are top priorities for fleets, and NREL partners know the lab’s portfolio of tools can pinpoint fuel efficiency and emissions-reduction strategies that also support operational the bottom line. NREL is one of the nation’s foremost leaders in medium- and heavy-duty vehicle research and development (R&D) and the go-to source for credible, validated transportation data. NREL developers have drawn on this expertise to create tools grounded in the real-world experiences of commercial and government fleets. Operators can use this comprehensive set of technology- and fuel-neutral tools to explore and analyze equipment and practices, energy-saving strategies, and other operational variables to ensure meaningful performance, financial, and environmental benefits.

  14. Barwood CNG Cab Fleet Study: Final Results

    SciTech Connect

    Whalen, P.; Kelly, K.; John, M.

    1999-05-03

    This report describes a fleet study conducted over a 12-month period to evaluate the operation of dedicated compress natural gas (CNG) Ford Crown Victoria sedans in a taxicab fleet. In the study, we assess the performance and reliability of the vehicles and the cost of operating the CNG vehicles compared to gasoline vehicles. The study results reveal that the CNG vehicles operated by this fleet offer both economic and environmental advantages. The total operating costs of the CNG vehicles were about 25% lower than those of the gasoline vehicles. The CNG vehicles performed as well as the gasoline vehicles, and were just as reliable. Barwood representatives and drivers have come to consider the CNG vehicles an asset to their business and to the air quality of the local community.

  15. Array measurements adapted to the number of available sensors: Theoretical and practical approach for ESAC method

    NASA Astrophysics Data System (ADS)

    Galiana-Merino, J. J.; Rosa-Cintas, S.; Rosa-Herranz, J.; Garrido, J.; Peláez, J. A.; Martino, S.; Delgado, J.

    2016-05-01

    Array measurements of ambient noise have become a useful technique to estimate the surface wave dispersion curves and subsequently the subsurface elastic parameters that characterize the studied soil. One of the logistical handicaps associated with this kind of measurements is the requirement of several stations recording at the same time, which limits their applicability in the case of research groups without enough infrastructure resources. In this paper, we describe the theoretical basis of the ESAC method and we deduce how the number of stations needed to implement any array layout can be reduced to only two stations. In this way, we propose a new methodology to implement an N stations array layout by using only M stations (M < N), which will be recording in different positions of the original prearranged N stations geometry at different times. We also provide some practical guidelines to implement the proposed approach and we show different examples where the obtained results confirm the theoretical foundations. Thus, the study carried out reflects that we can use a minimum of 2 stations to deploy any array layout originally designed for higher number of sensors.

  16. Self-Adaptive Strategy Based on Fuzzy Control Systems for Improving Performance in Wireless Sensors Networks

    PubMed Central

    Hernández Díaz, Vicente; Martínez, José-Fernán; Lucas Martínez, Néstor; del Toro, Raúl M.

    2015-01-01

    The solutions to cope with new challenges that societies have to face nowadays involve providing smarter daily systems. To achieve this, technology has to evolve and leverage physical systems automatic interactions, with less human intervention. Technological paradigms like Internet of Things (IoT) and Cyber-Physical Systems (CPS) are providing reference models, architectures, approaches and tools that are to support cross-domain solutions. Thus, CPS based solutions will be applied in different application domains like e-Health, Smart Grid, Smart Transportation and so on, to assure the expected response from a complex system that relies on the smooth interaction and cooperation of diverse networked physical systems. The Wireless Sensors Networks (WSN) are a well-known wireless technology that are part of large CPS. The WSN aims at monitoring a physical system, object, (e.g., the environmental condition of a cargo container), and relaying data to the targeted processing element. The WSN communication reliability, as well as a restrained energy consumption, are expected features in a WSN. This paper shows the results obtained in a real WSN deployment, based on SunSPOT nodes, which carries out a fuzzy based control strategy to improve energy consumption while keeping communication reliability and computational resources usage among boundaries. PMID:26393612

  17. Self-Adaptive Strategy Based on Fuzzy Control Systems for Improving Performance in Wireless Sensors Networks.

    PubMed

    Hernández Díaz, Vicente; Martínez, José-Fernán; Lucas Martínez, Néstor; del Toro, Raúl M

    2015-01-01

    The solutions to cope with new challenges that societies have to face nowadays involve providing smarter daily systems. To achieve this, technology has to evolve and leverage physical systems automatic interactions, with less human intervention. Technological paradigms like Internet of Things (IoT) and Cyber-Physical Systems (CPS) are providing reference models, architectures, approaches and tools that are to support cross-domain solutions. Thus, CPS based solutions will be applied in different application domains like e-Health, Smart Grid, Smart Transportation and so on, to assure the expected response from a complex system that relies on the smooth interaction and cooperation of diverse networked physical systems. The Wireless Sensors Networks (WSN) are a well-known wireless technology that are part of large CPS. The WSN aims at monitoring a physical system, object, (e.g., the environmental condition of a cargo container), and relaying data to the targeted processing element. The WSN communication reliability, as well as a restrained energy consumption, are expected features in a WSN. This paper shows the results obtained in a real WSN deployment, based on SunSPOT nodes, which carries out a fuzzy based control strategy to improve energy consumption while keeping communication reliability and computational resources usage among boundaries. PMID:26393612

  18. Launch site integration for mixed fleet operations

    NASA Technical Reports Server (NTRS)

    Scott, L. P.

    1990-01-01

    Launch site impacts and integration planning issues are presented to support launch operations for a mixed vehicle fleet (manned and cargo). Proposed ground systems and launch site configurations are described. Prelaunch processing scenarios and schedules are developed for candidate launch vehicles. Earth-to-orbit (ETO) vehicle architectures are presented to meet future launch requirements, including the Space Exploration Initiative (SEI). Flight vehicle design recommendations to enhance launch processing are discussed. The significance of operational designs for future launch vehicles is shown to be a critical factor in planning for mixed fleet launch site operations.

  19. Federal Fleet Files: Vol. 1, No. 2 - June 2009

    SciTech Connect

    2009-06-12

    June 2009 issue of the FEMP Federal Fleet Files monthly newsletter for the FEMP Federal Fleet Program that outlines vehicle, alternative fuel, infrastructure, and management strategy updates to Federal agencies.

  20. New methods for state estimation and adaptive observation of environmental flow systems leveraging coordinated swarms of sensor vehicles

    NASA Astrophysics Data System (ADS)

    Bewley, Thomas

    2015-11-01

    Accurate long-term forecasts of the path and intensity of hurricanes are imperative to protect property and save lives. Accurate estimations and forecasts of the spread of large-scale contaminant plumes, such as those from Deepwater Horizon, Fukushima, and recent volcanic eruptions in Iceland, are essential for assessing environment impact, coordinating remediation efforts, and in certain cases moving folks out of harm's way. The challenges in estimating and forecasting such systems include: (a) environmental flow modeling, (b) high-performance real-time computing, (c) assimilating measured data into numerical simulations, and (d) acquiring in-situ data, beyond what can be measured from satellites, that is maximally relevant for reducing forecast uncertainty. This talk will focus on new techniques for addressing (c) and (d), namely, data assimilation and adaptive observation, in both hurricanes and large-scale environmental plumes. In particular, we will present a new technique for the energy-efficient coordination of swarms of sensor-laden balloons for persistent, in-situ, distributed, real-time measurement of developing hurricanes, leveraging buoyancy control only (coupled with the predictable and strongly stratified flowfield within the hurricane). Animations of these results are available at http://flowcontrol.ucsd.edu/3dhurricane.mp4 and http://flowcontrol.ucsd.edu/katrina.mp4. We also will survey our unique hybridization of the venerable Ensemble Kalman and Variational approaches to large-scale data assimilation in environmental flow systems, and how essentially the dual of this hybrid approach may be used to solve the adaptive observation problem in a uniquely effective and rigorous fashion.

  1. Major Impact of Fleet Renewal Over Airports Located in the Most Important Region of Brazil

    NASA Technical Reports Server (NTRS)

    Maters, Rafael Waltz; deRoodeTorres, Roberta; Santo, Respicio A. Espirito, Jr.

    2003-01-01

    The present article discusses and analyses the major impacts of the Brazilian carriers fleet renewal regarding Brazilian airport infrastructure in the most important region of the country, the Southeast (SE). A brief historical overview of the country's airline fleet will be presented, demonstrating the need for its renewal (m fact, Brazilian carriers started a major fleet renewal program m the last five years), while analyzing the periods in which a new breed of aircraft was put into service by the major carriers operating in the SE region. The trend of operating the classic regional jets plus the forthcoming entry into service of the "large regional jets" (LRJ, 70-115 seaters) in several point-to-point routes are presented along with the country's carriers" reality of operating these former aircraft in several high-capacity and medium-range routes. The article will focus on the ability of four of the major Southeast's airports to cope with the fleet modernization, mainly due to the fact that the region studied is the most socioeconomic developed, by far, with the largest demand for air transportation, thus making the impacts much more perceptible for the communities and the airport management involved. With the emergence of these impacts, several new projects and investments are being discussed and pushed forward, despite budgetary constrains being a reality in almost every Brazilian city, even in the SE region. In view of this, the paper presents how the general planning could be carried out in order to adapt the airports' infrastructures in function of the proposed (and in some cases, necessary) fleet renewal. Ultimately, we will present the present picture and two future scenarios m order to determine the level of service in the existent passenger terminal facilities in the wake of the possible operation of several new aircraft. Keywords: Airline fleet planning, Airport planning, Regional development, Regional Jets.

  2. 46 CFR 296.21 - Participating Fleet Vessels.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 8 2010-10-01 2010-10-01 false Participating Fleet Vessels. 296.21 Section 296.21... OPERATORS MARITIME SECURITY PROGRAM (MSP) Priority for Granting Applications § 296.21 Participating Fleet... priority, tank vessels, in § 296.20, the second priority is applicable to Participating Fleet Vessels....

  3. 40 CFR 89.117 - Test fleet selection.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 20 2010-07-01 2010-07-01 false Test fleet selection. 89.117 Section... Certification Provisions § 89.117 Test fleet selection. (a) The manufacturer must select for testing, from each... of maximum torque and secondarily at rated speed. (b) Each engine in the test fleet must...

  4. 40 CFR 86.422-78 - Administrator's fleet.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 18 2010-07-01 2010-07-01 false Administrator's fleet. 86.422-78... 1978 and Later New Motorcycles, General Provisions § 86.422-78 Administrator's fleet. The Administrator... accordance with § 86.421. The number of vehicles selected shall not increase the size of the test fleet...

  5. A Chronological History of Federal Fleet Actions and Mandates

    SciTech Connect

    2011-04-22

    This chronological history of Federal fleet actions and mandates provides a year-by-year timeline of the acts, amendments, executive orders, and other regulations that affect Federal fleets. The fleet actions and mandates included in the timeline span from 1988 to 2009.

  6. Chronological History of Federal Fleet Actions and Mandates (Brochure)

    SciTech Connect

    Not Available

    2011-04-01

    This chronological history of Federal fleet actions and mandates provides a year-by-year timeline of the acts, amendments, executive orders, and other regulations that affect Federal fleets. The fleet actions and mandates included in the timeline span from 1988 to 2009.

  7. School Bus Fleet Safety: Planning and Development.

    ERIC Educational Resources Information Center

    Bieber, Robert M.

    1984-01-01

    To ensure worker safety, fleet safety managers need professional staffs, good access to top management, and sufficient authority to discharge their duties. Safety programs should include careful driver hiring; training, including orientation, testing, and practice; comprehensive accident reporting; and cooperative compliance programs with…

  8. Payload flight assignments: NASA mixed fleet

    NASA Technical Reports Server (NTRS)

    Starkey, Norman

    1993-01-01

    This mixed fleet manifest, which serves as the baseline for planning purposes, includes payload flight assignments for the Space Shuttle through FY 1995 and NASA expendable launch vehicle (EVL) missions through FY 1999. The FY 1996-1999 Shuttle manifest planning is omitted pending Space Station redesign. Also included in this document are a list of previous flights, payload requests, and payload/acronyms.

  9. Transportation capabilities of the existing cask fleet

    SciTech Connect

    Johnson, P.E.; Joy, D.S.; Wankerl, M.W.

    1991-01-01

    This paper describes a number of scenarios estimating the amount of spent nuclear fuel that could be transported to a Monitored Retrievable Storage (MRS) Facility by various combinations of existing cask fleets. To develop the scenarios, the data provided by the Transportation System Data Base (TSDB) were modified to reflect the additional time for cask turnaround resulting from various startup and transportation issues. With these more realistic speed and cask-handling assumptions, the annual transportation capability of a fleet consisting of all of the existing casks is approximately 46 metric tons of uranium (MTU). The most likely fleet of existing casks that would be made available to the Department of Energy (DOE) consists of two rail, three overweight truck, and six legal weight truck casks. Under the same transportation assumptions, this cask fleet is capable of approximately transporting 270 MTU/year. These ranges of capability is a result of the assumptions pertaining to the number of casks assumed to be available. It should be noted that this assessment assumes additional casks based on existing certifications are not fabricated. 5 refs., 4 tabs.

  10. Fleet DNA Project Data Summary Report (Presentation)

    SciTech Connect

    Walkowicz, K.; Duran, A.; Burton, E.

    2014-04-01

    This presentation includes graphical data summaries that highlight statistical trends for medium- and heavy-duty commercial fleet vehicles operating in a variety of vocations. It offers insight for the development of vehicle technologies that reduce costs, fuel consumption, and emission.

  11. Energy Efficient Medium Access Control Protocol for Clustered Wireless Sensor Networks with Adaptive Cross-Layer Scheduling.

    PubMed

    Sefuba, Maria; Walingo, Tom; Takawira, Fambirai

    2015-01-01

    This paper presents an Energy Efficient Medium Access Control (MAC) protocol for clustered wireless sensor networks that aims to improve energy efficiency and delay performance. The proposed protocol employs an adaptive cross-layer intra-cluster scheduling and an inter-cluster relay selection diversity. The scheduling is based on available data packets and remaining energy level of the source node (SN). This helps to minimize idle listening on nodes without data to transmit as well as reducing control packet overhead. The relay selection diversity is carried out between clusters, by the cluster head (CH), and the base station (BS). The diversity helps to improve network reliability and prolong the network lifetime. Relay selection is determined based on the communication distance, the remaining energy and the channel quality indicator (CQI) for the relay cluster head (RCH). An analytical framework for energy consumption and transmission delay for the proposed MAC protocol is presented in this work. The performance of the proposed MAC protocol is evaluated based on transmission delay, energy consumption, and network lifetime. The results obtained indicate that the proposed MAC protocol provides improved performance than traditional cluster based MAC protocols. PMID:26393608

  12. Energy Efficient Medium Access Control Protocol for Clustered Wireless Sensor Networks with Adaptive Cross-Layer Scheduling

    PubMed Central

    Sefuba, Maria; Walingo, Tom; Takawira, Fambirai

    2015-01-01

    This paper presents an Energy Efficient Medium Access Control (MAC) protocol for clustered wireless sensor networks that aims to improve energy efficiency and delay performance. The proposed protocol employs an adaptive cross-layer intra-cluster scheduling and an inter-cluster relay selection diversity. The scheduling is based on available data packets and remaining energy level of the source node (SN). This helps to minimize idle listening on nodes without data to transmit as well as reducing control packet overhead. The relay selection diversity is carried out between clusters, by the cluster head (CH), and the base station (BS). The diversity helps to improve network reliability and prolong the network lifetime. Relay selection is determined based on the communication distance, the remaining energy and the channel quality indicator (CQI) for the relay cluster head (RCH). An analytical framework for energy consumption and transmission delay for the proposed MAC protocol is presented in this work. The performance of the proposed MAC protocol is evaluated based on transmission delay, energy consumption, and network lifetime. The results obtained indicate that the proposed MAC protocol provides improved performance than traditional cluster based MAC protocols. PMID:26393608

  13. Cross Layer Adaptation of Check Intervals in Low Power Listening MAC Protocols for Lifetime Improvement in Wireless Sensor Networks

    PubMed Central

    Escolar, Soledad; Chessa, Stefano; Carretero, Jesús; Marinescu, Maria-Cristina

    2012-01-01

    Preamble sampling-based MAC protocols designed for Wireless Sensor Networks (WSN) are aimed at prolonging the lifetime of the nodes by scheduling their times of activity. This scheduling exploits node synchronization to find the right trade-off between energy consumption and delay. In this paper we consider the problem of node synchronization in preamble sampling protocols. We propose Cross Layer Adaptation of Check intervals (CLAC), a novel protocol intended to reduce the energy consumption of the nodes without significantly increasing the delay. Our protocol modifies the scheduling of the nodes based on estimating the delay experienced by a packet that travels along a multi-hop path. CLAC uses routing and MAC layer information to compute a delay that matches the packet arrival time. We have implemented CLAC on top of well-known routing and MAC protocols for WSN, and we have evaluated our implementation using the Avrora simulator. The simulation results confirm that CLAC improves the network lifetime at no additional packet loss and without affecting the end-to-end delay. PMID:23112613

  14. Adaptive cancellation of floor vibrations in standing ballistocardiogram measurements using a seismic sensor as a noise reference.

    PubMed

    Inan, Omer T; Etemadi, Mozziyar; Widrow, Bernard; Kovacs, Gregory T A

    2010-03-01

    An adaptive noise canceller was used to reduce the effect of floor vibrations on ballistocardiogram (BCG) measurements from a modified electronic bathroom scale. A seismic sensor was placed next to the scale on the floor and used as the noise reference input to the noise canceller. BCG recordings were acquired from a healthy subject while another person stomped around the scale, thus causing increased floor vibrations. The noise canceller substantially eliminated the artifacts in the BCG signal due to these vibrations without distorting the morphology of the measured BCG. Additionally, recordings were obtained from another subject standing inside a parked bus while the engine was running. The artifacts due to the vibrations of the engine, and the other vehicles moving on the road next to the bus, were also effectively eliminated by the noise canceller. The system with automatic floor vibration cancellation could be used to increase BCG measurement robustness in home monitoring applications. Additionally, the noise cancellation approach may enable BCG recording in ambulances-or other transport vehicles-where noninvasive hemodynamic monitoring may otherwise not be feasible. PMID:19362900

  15. 41 CFR 102-34.330 - What is the Federal Fleet Report?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Fleet Report? 102-34.330 Section 102-34.330 Public Contracts and Property Management Federal Property... MANAGEMENT Federal Fleet Report § 102-34.330 What is the Federal Fleet Report? The Federal Fleet Report (FFR) is an annual summary of Federal fleet statistics based upon fleet composition at the end of...

  16. Optimizing Multibeam Data Across the U.S. Academic Research Fleet

    NASA Astrophysics Data System (ADS)

    Ferrini, V.; Beaudoin, J.; Johnson, P. D.

    2012-12-01

    Multibeam sonars are fundamental mapping tools for a wide range of oceanographic studies throughout the global oceans. Initially installed on only a few academic research vessels, they have become standard sensors across global- and ocean-class ships in the U.S. academic research fleet. While ongoing efforts including the Rolling Deck to Repository (R2R, http://rvdata.us) and the Global Multi-Resolution Topography Synthesis (GMRT, http://www.marine-geo.org/portals/gmrt) are focused on data documentation, preservation, synthesis and dissemination, the Multibeam Advisory Committee (MAC, http://mac.unols.org) was recently established with the primary goal of optimizing multibeam data quality during acquisition. Our strategy is to engage operators, technical specialists and users to develop common protocols, guidelines and tools for use across the fleet. Technical teams are focused on specific aspects of multibeam sonar operation and maintenance, including Sea Acceptance, Acoustic Noise, and Quality Assurance. Key to our effort is working with the community of stakeholders to ensure that protocols and tools suit the needs of the community and can be easily implemented across the fleet. Although MAC efforts are initially focused on deep water systems in the US Academic Research Fleet, we recognize that our community of stakeholders is much broader and also includes operators and users of shallow water. All MAC-generated reports, guidelines and software tools, as well as links to related online resources are being made publicly available through the MAC website (http://mac.unols.org).

  17. How Fleet Bank fought employee flight.

    PubMed

    Nalbantian, Haig R; Szostak, Anne

    2004-04-01

    In the late 1990s, Fleet Bank was facing high and rising employee turnover, particularly in its retail operations. Overall turnover had reached 25% annually, and among some groups, such as tellers and customer service reps, turnover was as high as 40%. Using a new methodology developed by Mercer Human Resource Consulting, Fleet set out to determine why so many employees were leaving and what could be done to retain them. It began examining data from HR, finance, operations, and sales about employee behavior and the factors that influence it in different locations and labor markets, departments or work groups, in positions with different pay and benefits, and under different supervisors. Fleet's analysis showed that people were leaving not so much for better pay--their personal testimony notwithstanding--but for broader experience, which they thought would enhance their marketability. Additionally, the analysis revealed a link between the turnover problem and the company's busy history of mergers and acquisitions. Fleet's mergers and acquisitions. frequently meant that it had to consolidate operations. That consolidation resulted in layoffs, which provoked higher levels of voluntary turnover, perhaps because remaining employees began worrying about their job security. While the obvious solution to the turnover problem might have been to compensate the remaining employees--say, with higher pay--the more effective and less costly solution, Fleet discovered, was to focus on employees' career opportunities within the company. Those who moved up the hierarchy, or who even made lateral moves, stayed longer. By offering better internal opportunities for career development, the bank was able to stanch much of the hemorrhaging in personnel. Its solutions required only modest investments, which in the end saved the company millions of dollars. PMID:15077372

  18. NSF/ESF Workshop on Smart Structures and Advanced Sensors, Santorini Island, Greece, June 26-28, 2005: Structural Actuation and Adaptation Working Group

    NASA Technical Reports Server (NTRS)

    Figueroa, Fernando; Tomizuka, Masayoshi; Bergman, Lawrence; Carpenter, Bernie; Salzano, Carmine; Bairrao, rogerio; Deraemaker, Arnaud; Magonette, Georges; Rodellar, Jose; Kadirkamanathan, Visaken

    2005-01-01

    This document is a result of discussions that took place during the workshop. It describes current state of research and development (R&D) in the areas of structural actuation and adaptation in the context of smart structures and advanced sensors (SS&AS), and provides an outlook to guide future R&D efforts to develop technologies needed to build SS&AS. The discussions took place among the members of the Structural Actuation and Adaptation Working Group, as well as in general sessions including all four working groups. Participants included members of academia, industry, and government from the US and Europe, and representatives from China, Japan, and Korea.

  19. CleanFleet. Volume 2, Project Design and Implementation

    SciTech Connect

    1995-12-01

    The CleanFleet alternative fuels demonstration project evaluated five alternative motorfuels in commercial fleet service over a two-year period. The five fuels were compressed natural gas, propane gas, California Phase 2 reformulated gasoline (RFG), M-85 (85 percent methanol and 15 percent RFG), and electric vans. Eight-four vans were operated on the alternative fuels and 27 vans were operated on gasoline as baseline controls. Throughout the demonstration information was collected on fleet operations, vehicle emissions, and fleet economics. In this volume of the CleanFleet findings, the design and implementation of the project are summarized.

  20. Application of Strategic Planning Process with Fleet Level Analysis Methods

    NASA Technical Reports Server (NTRS)

    Mavris, Dimitri N.; Pfaender, Holger; Jimenez, Hernando; Garcia, Elena; Feron, Eric; Bernardo, Jose

    2016-01-01

    The goal of this work is to quantify and characterize the potential system-wide reduction of fuel consumption and corresponding CO2 emissions, resulting from the introduction of N+2 aircraft technologies and concepts into the fleet. Although NASA goals for this timeframe are referenced against a large twin aisle aircraft we consider their application across all vehicle classes of the commercial aircraft fleet, from regional jets to very large aircraft. In this work the authors describe and discuss the formulation and implementation of the fleet assessment by addressing the main analytical components: forecasting, operations allocation, fleet retirement, fleet replacement, and environmental performance modeling.

  1. Role of Energy Sensor TlpD of Helicobacter pylori in Gerbil Colonization and Genome Analyses after Adaptation in the Gerbil

    PubMed Central

    Behrens, Wiebke; Schweinitzer, Tobias; Bal, Joena; Dorsch, Martina; Bleich, André; Kops, Friederike; Brenneke, Birgit; Didelot, Xavier; Suerbaum, Sebastian

    2013-01-01

    Helicobacter pylori maintains colonization in its human host using a limited set of taxis sensors. TlpD is a proposed energy taxis sensor of H. pylori and dominant under environmental conditions of low bacterial energy yield. We studied the impact of H. pylori TlpD on colonization in vivo using a gerbil infection model which closely mimics the gastric physiology of humans. A gerbil-adapted H. pylori strain, HP87 P7, showed energy-dependent behavior, while its isogenic tlpD mutant lost it. A TlpD-complemented strain regained the wild-type phenotype. Infection of gerbils with the complemented strain demonstrated that TlpD is important for persistent infection in the antrum and corpus and suggested a role of TlpD in horizontal navigation and persistent corpus colonization. As a part of the full characterization of the model and to gain insight into the genetic basis of H. pylori adaptation to the gerbil, we determined the complete genome sequences of the gerbil-adapted strain HP87 P7, two HP87 P7 tlpD mutants before and after gerbil passage, and the original human isolate, HP87. The integrity of the genome, including that of a functional cag pathogenicity island, was maintained after gerbil adaptation. Genetic and phenotypic differences between the strains were observed. Major differences between the gerbil-adapted strain and the human isolate emerged, including evidence of recent recombination. Passage of the tlpD mutant through the gerbil selected for gain-of-function variation in a fucosyltransferase gene, futC (HP0093). In conclusion, a gerbil-adapted H. pylori strain with a stable genome has helped to establish that TlpD has important functions for persistent colonization in the stomach. PMID:23836820

  2. Adaptive optical zoom sensor.

    SciTech Connect

    Sweatt, William C.; Bagwell, Brett E.; Wick, David Victor

    2005-11-01

    In order to optically vary the magnification of an imaging system, continuous mechanical zoom lenses require multiple optical elements and use fine mechanical motion to precisely adjust the separations between individual or groups of lenses. By incorporating active elements into the optical design, we have designed and demonstrated imaging systems that are capable of variable optical magnification with no macroscopic moving parts. Changing the effective focal length and magnification of an imaging system can be accomplished by adeptly positioning two or more active optics in the optical design and appropriately adjusting the optical power of those elements. In this application, the active optics (e.g. liquid crystal spatial light modulators or deformable mirrors) serve as variable focal-length lenses. Unfortunately, the range over which currently available devices can operate (i.e. their dynamic range) is relatively small. Therefore, the key to this concept is to create large changes in the effective focal length of the system with very small changes in the focal lengths of individual elements by leveraging the optical power of conventional optical elements surrounding the active optics. By appropriately designing the optical system, these variable focal-length lenses can provide the flexibility necessary to change the overall system focal length, and therefore magnification, that is normally accomplished with mechanical motion in conventional zoom lenses.

  3. ADAPTIVE MONITORING TO ENHANCE WATER SENSOR CAPABILITIES FOR CHEMICAL AND BIOLOGICAL CONTAMINANT DETECTION IN DRINKING WATER SYSTEMS

    EPA Science Inventory

    Optoelectronic and other conventional water quality sensors offer a potential for real-time online detection of chemical and biological contaminants in a drinking water supply and distribution system. The nature of the application requires sensors of detection capabilities at lo...

  4. Size and transportation capabilities of the existing US cask fleet

    SciTech Connect

    Danese, F.L. ); Johnson, P.E.; Joy, D.S. )

    1990-01-01

    This study investigates the current spent nuclear fuel cask fleet capability in the United States. In addition, it assesses the degree to which the current fleet would be available, as a contingency, until proposed Office of Civilian Radioactive Waste Management casks become operational. A limited fleet of ten spent fuel transportation casks is found to be readily available for use in Federal waste management efforts over the next decade.

  5. Mashup - Based End User Interface for Fleet Monitoring

    NASA Astrophysics Data System (ADS)

    Popa, M.; Popa, A. S.; Slavici, T.; Darvasi, D.

    Fleet monitoring of commercial vehicles has received a major attention in the last period. A good monitoring solution increases the fleet efficiency by reducing the transportation durations, by optimizing the planned routes and by providing determinism at the intermediate and final destinations. This paper presents a fleet monitoring system for commercial vehicles using the Internet as data infrastructure. The mashup concept was implemented for creating a user interface.

  6. Radioactive Legacy of the Russian Pacific Fleet Operations. Final Report

    SciTech Connect

    Compton, K. L.; Novikov, V.M.; Parker, F.L.; Sivintsev, Y.U.

    2003-03-25

    There have been extensive studies of the current and potential environmental impact of Russian Northern fleet activities. However, despite the fact that the total number of ships in both fleets are comparable, there have been very few studies published in the open literature of the impact of the Pacific fleet. This study of the Pacific fleet's impact on neighboring countries was undertaken to partially remedy this lack of analysis. This study is focused on an evaluation of the inventory of major sources of radioactive material associated with the decommissioning of nuclear submarines, and an evaluation of releases to the atmosphere and their long-range (>100km) transboundary transport.

  7. A new energy-harvesting device system for wireless sensors, adaptable to on-site monitoring of MR damper motion

    NASA Astrophysics Data System (ADS)

    Yu, Miao; Peng, Youxiang; Wang, Siqi; Fu, Jie; Choi, S. B.

    2014-07-01

    Under extreme service conditions in vehicle suspension systems, some defects exist in the hardening, bodying, and poor temperature stability of magnetorheological (MR) fluid. These defects can cause weak and even invalid performance in the MR fluid damper (MR damper for short). To ensure the effective validity of the practical applicability of the MR damper, one must implement an online state-monitoring sensor to monitor several performance factors, such as acceleration. In this empirical work, we propose a new energy-harvesting device system for the wireless sensor system of an MR damper. The monitoring sensor system consists of several components, such as an energy-harvesting device, energy-management circuit, and wireless sensor node. The electrical energy harvested from the kinetic energy of the MR fluid that flows within the MR damper can be automatically charged and discharged with the help of an energy-management circuit for the wireless sensor node. After verifying good performance from each component, an experimental apparatus is built to evaluate the feasibility of the proposed self-powered wireless sensor system. The measured results of pressure, temperature, and acceleration data within the MR damper clearly demonstrate the practical applicability of monitoring the operating work states of the MR damper when it is subjected to sinusoidal excitation.

  8. 78 FR 23935 - Federal Acquisition Regulation; Information Collection; Contractor Use of Interagency Fleet...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-04-23

    ... Regulation; Information Collection; Contractor Use of Interagency Fleet Management System Vehicles AGENCY... previously approved information collection requirement concerning contractor use of interagency fleet... Collection 9000- 0032, Contractor Use of Interagency Fleet Management System Vehicles, by any of...

  9. 40 CFR 88.310-94 - Applicability to covered Federal fleets.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...) AIR PROGRAMS (CONTINUED) CLEAN-FUEL VEHICLES Clean-Fuel Fleet Program § 88.310-94 Applicability to covered Federal fleets. (a) Compliance by Federal vehicles. As per section 258(a) of the Act, fleets...

  10. 40 CFR 88.310-94 - Applicability to covered Federal fleets.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...) AIR PROGRAMS (CONTINUED) CLEAN-FUEL VEHICLES Clean-Fuel Fleet Program § 88.310-94 Applicability to covered Federal fleets. (a) Compliance by Federal vehicles. As per section 258(a) of the Act, fleets...

  11. 40 CFR 88.310-94 - Applicability to covered Federal fleets.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...) AIR PROGRAMS (CONTINUED) CLEAN-FUEL VEHICLES Clean-Fuel Fleet Program § 88.310-94 Applicability to covered Federal fleets. (a) Compliance by Federal vehicles. As per section 258(a) of the Act, fleets...

  12. Condition Monitoring of the SSE Generation Fleet

    NASA Astrophysics Data System (ADS)

    Twiddle, J.; Muthuraman, S.; Connolly, N.

    2012-05-01

    SSE (previously known as Scottish and Southern Energy) operates a diverse portfolio of generation plant, including coal, gas and renewable plant with a total generation capacity of 11,375MW (Sept 2011). In recent years a group of specialists dedicated to providing condition monitoring services has been established at the Equipment Performance Centre (EPC) based at Knottingley, West Yorkshire. We aim to illustrate the role of the EPC and the methods used for monitoring the generation fleet with the objective of maintaining asset integrity, reducing risk of plant failure and unplanned outages and describe the challenges which have been overcome in establishing the EPC. This paper describes methods including vibration and process data analysis, model-based techniques and on-site testing used for monitoring of generation plant, including gas turbines, steam turbines, generators and steam raising plant. These condition monitoring processes utilise available data, adding value to the business, by bringing services in-house and capturing knowledge of plant operation for the benefit of the whole fleet.

  13. Plug-In Electric Vehicle Handbook for Fleet Managers (Brochure)

    SciTech Connect

    Not Available

    2012-04-01

    Plug-in electric vehicles (PEVs) are entering the automobile market and are viable alternatives to conventional vehicles. This guide for fleet managers describes the basics of PEV technology, PEV benefits for fleets, how to select the right PEV, charging a PEV, and PEV maintenance.

  14. 40 CFR 86.421-78 - Test fleet.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 18 2010-07-01 2010-07-01 false Test fleet. 86.421-78 Section 86.421... Later New Motorcycles, General Provisions § 86.421-78 Test fleet. (a) A test vehicle will be selected by... prior to the start of testing and not later than 30 days following notification of the test...

  15. 40 CFR 86.418-78 - Test fleet selection.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 18 2010-07-01 2010-07-01 false Test fleet selection. 86.418-78 Section 86.418-78 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS... 1978 and Later New Motorcycles, General Provisions § 86.418-78 Test fleet selection. (a) Test...

  16. 40 CFR 86.422-78 - Administrator's fleet.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 19 2013-07-01 2013-07-01 false Administrator's fleet. 86.422-78 Section 86.422-78 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS... 1978 and Later New Motorcycles, General Provisions § 86.422-78 Administrator's fleet. The...

  17. 40 CFR 86.422-78 - Administrator's fleet.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 19 2014-07-01 2014-07-01 false Administrator's fleet. 86.422-78 Section 86.422-78 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS... 1978 and Later New Motorcycles, General Provisions § 86.422-78 Administrator's fleet. The...

  18. 40 CFR 86.422-78 - Administrator's fleet.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 18 2011-07-01 2011-07-01 false Administrator's fleet. 86.422-78 Section 86.422-78 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS... 1978 and Later New Motorcycles, General Provisions § 86.422-78 Administrator's fleet. The...

  19. 40 CFR 86.422-78 - Administrator's fleet.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 19 2012-07-01 2012-07-01 false Administrator's fleet. 86.422-78 Section 86.422-78 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS... 1978 and Later New Motorcycles, General Provisions § 86.422-78 Administrator's fleet. The...

  20. Developing a Fleet Standardization Index for Airline Planning

    NASA Technical Reports Server (NTRS)

    deBorgesPan, Alexis George; EspiritoSanto, Respicio A., Jr.

    2003-01-01

    Quantifying subjective aspects is a difficult task that requires a great dedication of time from researchers and analysts. Nevertheless, one of the main objectives of it is to pave the way for a better understanding of the focused aspects. Fleet standardization is one of these subjective aspects that is extremely difficult to mm into numbers. Although, it is of great importance to know the benefits that may come with a higher level of standardization for airlines, which may be economical advantages, maintenance facilitation and others. A more standardized fleet may represent lower costs of operations and maintenance facilitation and others. A more standardized fleet may represent lower costs of operations and maintenance plus a much better planning of routes and flights. This study presents the first step on developing an index, hereto called "Fleet Standardization Index" or FSI (or IPF in Portuguese, for "Indice de Padronizacao de Frotas"), that will allow senior airline planners to compare different fleets and also simulate some results from maintaining or renewing their fleets. Although being a preliminary study, the results obtained may already be tested to compare different fleets (different airlines) and also analyze some possible impacts of a fleet renewal before it takes place. Therefore, the main objective of this paper is to introduce the proposed IPF index and to demonstrate that it is inversely proportional to the number of different airplane models, engines and other equipment, such as avionics.

  1. 40 CFR 86.421-78 - Test fleet.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 19 2014-07-01 2014-07-01 false Test fleet. 86.421-78 Section 86.421... Later New Motorcycles, General Provisions § 86.421-78 Test fleet. (a) A test vehicle will be selected by... to operate and test additional vehicles which are identical to those selected by the...

  2. 40 CFR 86.421-78 - Test fleet.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 19 2012-07-01 2012-07-01 false Test fleet. 86.421-78 Section 86.421... Later New Motorcycles, General Provisions § 86.421-78 Test fleet. (a) A test vehicle will be selected by... to operate and test additional vehicles which are identical to those selected by the...

  3. Sensor response rate accelerator

    DOEpatents

    Vogt, Michael C.

    2002-01-01

    An apparatus and method for sensor signal prediction and for improving sensor signal response time, is disclosed. An adaptive filter or an artificial neural network is utilized to provide predictive sensor signal output and is further used to reduce sensor response time delay.

  4. The Neural Mechanisms of Social Learning from Fleeting Experience with Pain

    PubMed Central

    Fan, Yang-Teng; Chen, Chenyi; Cheng, Yawei

    2016-01-01

    Social learning is critical for humans to adapt and cope with rapidly changing surroundings. Although, neuroscience has focused on associative learning and pain empathy, the neural mechanisms of social learning through fleeting pain remains to be determined. This functional MRI study included three participant groups, to investigate how the neuro-hemodynamic response and subjective evaluation in response to the observation of hand actions were modulated by first-hand experience (FH), as well as indirect experience through social-observational (SO), and verbal-informed (VI) learning from fleeting pain. The results indicated, that these three learning groups share the common neuro-hemodynamic activations in the brain regions implicated in emotional awareness, memory, mentalizing, perspective taking, and emotional regulation. The anterior insular cortex (AIC) was commonly activated during these learning procedures. The amygdala was only activated by the FH. Dynamic causal modeling further indicated, that the SO and VI learning exhibited weaker connectivity strength from the AIC to superior frontal gyrus than did the FH. These findings demonstrate, that social learning elicits distinct neural responses from associative learning. The ontogeny of human empathy could be better understood with social learning from fleeting experience with pain. PMID:26903828

  5. The Neural Mechanisms of Social Learning from Fleeting Experience with Pain.

    PubMed

    Fan, Yang-Teng; Chen, Chenyi; Cheng, Yawei

    2016-01-01

    Social learning is critical for humans to adapt and cope with rapidly changing surroundings. Although, neuroscience has focused on associative learning and pain empathy, the neural mechanisms of social learning through fleeting pain remains to be determined. This functional MRI study included three participant groups, to investigate how the neuro-hemodynamic response and subjective evaluation in response to the observation of hand actions were modulated by first-hand experience (FH), as well as indirect experience through social-observational (SO), and verbal-informed (VI) learning from fleeting pain. The results indicated, that these three learning groups share the common neuro-hemodynamic activations in the brain regions implicated in emotional awareness, memory, mentalizing, perspective taking, and emotional regulation. The anterior insular cortex (AIC) was commonly activated during these learning procedures. The amygdala was only activated by the FH. Dynamic causal modeling further indicated, that the SO and VI learning exhibited weaker connectivity strength from the AIC to superior frontal gyrus than did the FH. These findings demonstrate, that social learning elicits distinct neural responses from associative learning. The ontogeny of human empathy could be better understood with social learning from fleeting experience with pain. PMID:26903828

  6. Pervasive Adaptation in Car Crowds

    NASA Astrophysics Data System (ADS)

    Ferscha, Alois; Riener, Andreas

    Advances in the miniaturization and embedding of electronics for microcomputing, communication and sensor/actuator systems, have fertilized the pervasion of technology into literally everything. Pervasive computing technology is particularly flourishing in the automotive domain, exceling the “smart car”, embodying intelligent control mechanics, intelligent driver assistance, safety and comfort systems, navigation, tolling, fleet management and car-to-car interaction systems, as one of the outstanding success stories of pervasive computing. This paper raises the issue of the socio-technical phenomena emerging from the reciprocal interrelationship between drivers and smart cars, particularly in car crowds. A driver-vehicle co-model (DVC-model) is proposed, expressing the complex interactions between the human driver and the in-car and on-car technologies. Both explicit (steering, shifting, overtaking), as well as implicit (body posture, respiration) interactions are considered, and related to the drivers vital state (attentive, fatigue, distracted, aggressive). DVC-models are considered as building blocks in large scale simulation experiments, aiming to analyze and understand adaptation phenomena rooted in the feed-back loops among individual driver behavior and car crowds.

  7. Analysis of the NAFA fleet data base: passenger cars only

    SciTech Connect

    Shonka, D.

    1980-09-01

    To assess the potential market penetration of new vehicular concepts, it is first necessary to determine the current level of demand in terms of physical capabilities and economic constraints. The survey described in this report attempts to measure these characteristics for the fleet market sector in the U.S. The data analyzed come from a survey taken in March 1979 of members of the National Association of Fleet Administrators (NAFA). Each respondent was asked to specify a set of characteristics for electric cars that would meet his specific fleet demands and assign the maximum price he would be willing to pay for each option. From the 139 responses, it is possible to relate the physical specifications of fleet vehicles to economic utility. Two other reports (BNL-51286; BNL-51312) deal with the simulator (CPEN) which was designed by BNL to estimate market penetration rates of new technologies in the fleet market, using the data base described within this report: Joseph R. Wagner, A Method for Estimating TeA methodhnological Penetration Rates in Commercial Automobile Fleets, BNL 51312, May 1980, and Richard Weil, Fleet Car Market Penetration Simulator (CPEN): A User's Guide, BNL 51286, August 1980.

  8. Multi-source feature extraction and target recognition in wireless sensor networks based on adaptive distributed wavelet compression algorithms

    NASA Astrophysics Data System (ADS)

    Hortos, William S.

    2008-04-01

    Proposed distributed wavelet-based algorithms are a means to compress sensor data received at the nodes forming a wireless sensor network (WSN) by exchanging information between neighboring sensor nodes. Local collaboration among nodes compacts the measurements, yielding a reduced fused set with equivalent information at far fewer nodes. Nodes may be equipped with multiple sensor types, each capable of sensing distinct phenomena: thermal, humidity, chemical, voltage, or image signals with low or no frequency content as well as audio, seismic or video signals within defined frequency ranges. Compression of the multi-source data through wavelet-based methods, distributed at active nodes, reduces downstream processing and storage requirements along the paths to sink nodes; it also enables noise suppression and more energy-efficient query routing within the WSN. Targets are first detected by the multiple sensors; then wavelet compression and data fusion are applied to the target returns, followed by feature extraction from the reduced data; feature data are input to target recognition/classification routines; targets are tracked during their sojourns through the area monitored by the WSN. Algorithms to perform these tasks are implemented in a distributed manner, based on a partition of the WSN into clusters of nodes. In this work, a scheme of collaborative processing is applied for hierarchical data aggregation and decorrelation, based on the sensor data itself and any redundant information, enabled by a distributed, in-cluster wavelet transform with lifting that allows multiple levels of resolution. The wavelet-based compression algorithm significantly decreases RF bandwidth and other resource use in target processing tasks. Following wavelet compression, features are extracted. The objective of feature extraction is to maximize the probabilities of correct target classification based on multi-source sensor measurements, while minimizing the resource expenditures at

  9. Sensor-fault tolerant control of a powered lower limb prosthesis by mixing mode-specific adaptive Kalman filters.

    PubMed

    Dutta, Anirban; Koerding, Konrad; Perreault, Eric; Hargrove, Levi

    2011-01-01

    Machine learning methods for interfacing humans with machines is an emerging area. Here we propose a novel algorithm for interfacing humans with powered lower limb prostheses for restoring control of naturalistic gait following amputation. Unlike most previous neural machine interfaces, our approach fuses control information from the user with sensor information from the prosthesis to approximate the closed loop behavior of the unimpaired sensorimotor system. We present a Bayesian framework to control an artificial knee by probabilistically mixing of process state estimates from different Kalman filters, each addressing separate regimes of locomotion such as level ground walking, walking up a ramp, and walking down a ramp. We show its utility as a mode classifier that is tolerant to temporary sensor faults which are frequently experienced in practical applications. PMID:22255142

  10. Adaptive switching frequency buck DC—DC converter with high-accuracy on-chip current sensor

    NASA Astrophysics Data System (ADS)

    Jinguang, Jiang; Fei, Huang; Zhihui, Xiong

    2015-05-01

    A current-mode PWM buck DC—DC converter is proposed. With the high-accuracy on-chip current sensor, the switching frequency can be selected automatically according to load requirements. This method improves efficiency and obtains an excellent transient response. The high accuracy of the current sensor is achieved by a simple switch technique without an amplifier. This has the direct benefit of reducing power dissipation and die size. Additionally, a novel soft-start circuit is presented to avoid the inrush current at the starting up state. Finally, this DC—DC converter is fabricated with the 0.5 μm standard CMOS process. The chip occupies 3.38 mm2. The accuracy of the proposed current sensor can achieve 99.5% @ 200 mA. Experimental results show that the peak efficiency is 91.8%. The input voltage ranges from 5 to 18 V, while a 2 A load current can be obtained. Project supported by the National Natural Science Foundation of China (No. 41274047), the Natural Science Foundation of Jiangsu Province (No. BK2012639), the Science and Technology Enterprises in Jiangsu Province Technology Innovation Fund (No. BC2012121), and the Changzhou Science and Technology Support (Industrial) Project (No. CE20120074).

  11. Electric vehicles look promising for use in utility fleets

    SciTech Connect

    Minner, D.

    1984-06-01

    The Electric Vehicle Development Corp. (EVDV) expects EV fleets to find a market for urban driving, especially among service fleets, once mass production begins. Electric utilities joined to form EVDC in order to keep abreast of research developments and the results of demonstrations taking place in several cities, where driver acceptance in utility demonstration programs is high. Major auto makers still need persuasion to develop a commercial prototype. Marketing will focus on controlled fleets having the management skills and the motivation to make the program work.

  12. Preliminary assessment of fleets covered by the Energy Policy Act

    SciTech Connect

    Hu, P.S.; Davis, S.C.; Wang, M.Q.

    1994-12-31

    To facilitate the goal of decreasing oil imports by 10 percent by the year 2000 and 30 percent by 2010, two sections of the Energy Policy Act encourage and mandate alternative fuel vehicles in the acquisition of fleet vehicles. The first step in estimating the contribution of these mandates toward meeting the aforementioned goal entails identifying affected fleets. This paper presents a preliminary assessment of potential vehicle fleet coverage. Only a limited number of companies in the methanol, ethanol, and hydrogen industries are likely to quality for this mandate. Whereas, many of the oil producers, petroleum refiners, and electricity companies are likely to be regulated.

  13. Perspectives on AFVs: State and city government fleet manager survey

    SciTech Connect

    Whalen, P.

    1999-02-01

    In an effort to reduce national dependence on imported oil and to improve urban air quality, the US Department of Energy (DOE) is promoting the development and deployment of alternative fuels and alternative fuel vehicles (AFVs). To support this activity, DOE has directed the National Renewable Energy Laboratory (NREL) to develop and conduct projects to evaluate the performance and acceptability of light-duty AFVs compared to similar gasoline vehicles. As part of this effort, NREL has undertaken a number of evaluation projects, including conducting telephone surveys with fleet managers and drivers of AFVs in the federal fleet. This report summarizes the results of the survey of state and city government fleet managers.

  14. Maintaining the safety of an aging fleet of aircraft

    NASA Technical Reports Server (NTRS)

    Hoggard, Amos W.

    1992-01-01

    The current status of the Douglas Aging Fleet is examined in light of increasing concern for the possibility of the onset of widespread cracking and recent industry activity to minimize the concern. A fleet monitoring program together with an augmented maintenance program is proposed as a possible means to reduce the concern. Six candidate options for maintenance program augmentation are examined which have been shown to be effective in detection of widespread fatigue damage. A brief example of how this system might be applied to the DC-9 Fleet is presented.

  15. 40 CFR 88.310-94 - Applicability to covered Federal fleets.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... fleets. 88.310-94 Section 88.310-94 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) CLEAN-FUEL VEHICLES Clean-Fuel Fleet Program § 88.310-94 Applicability to covered Federal fleets. (a) Compliance by Federal vehicles. As per section 258(a) of the Act, fleets...

  16. 41 CFR 102-34.340 - Do we need a fleet management information system?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 41 Public Contracts and Property Management 3 2010-07-01 2010-07-01 false Do we need a fleet... VEHICLE MANAGEMENT Federal Fleet Report § 102-34.340 Do we need a fleet management information system? Yes, you must have a fleet management information system at the department or agency level that —...

  17. 50 CFR 660.338 - Limited entry permits-small fleet.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 50 Wildlife and Fisheries 9 2010-10-01 2010-10-01 false Limited entry permits-small fleet. 660.338... Groundfish Fisheries § 660.338 Limited entry permits-small fleet. (a) Small limited entry fisheries fleets... another vessel that will continue to operate in the same certified small fleet, provided that the...

  18. 41 CFR 101-39.104-1 - Consolidations into a fleet management system.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... fleet management system. 101-39.104-1 Section 101-39.104-1 Public Contracts and Property Management..., TRANSPORTATION, AND MOTOR VEHICLES 39-INTERAGENCY FLEET MANAGEMENT SYSTEMS 39.1-Establishment, Modification, and Discontinuance of Interagency Fleet Management Systems § 101-39.104-1 Consolidations into a fleet...

  19. 40 CFR 80.59 - General test fleet requirements for vehicle testing.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 16 2010-07-01 2010-07-01 false General test fleet requirements for... test fleet requirements for vehicle testing. (a) The test fleet must consist of only 1989-91 MY... test fleet shall have no fewer than 4,000 miles of accumulated mileage prior to being included in...

  20. 41 CFR 101-39.104 - Notice of establishment of a fleet management system.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... of a fleet management system. 101-39.104 Section 101-39.104 Public Contracts and Property Management..., TRANSPORTATION, AND MOTOR VEHICLES 39-INTERAGENCY FLEET MANAGEMENT SYSTEMS 39.1-Establishment, Modification, and Discontinuance of Interagency Fleet Management Systems § 101-39.104 Notice of establishment of a fleet...

  1. 41 CFR 101-39.104 - Notice of establishment of a fleet management system.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ..., TRANSPORTATION, AND MOTOR VEHICLES 39-INTERAGENCY FLEET MANAGEMENT SYSTEMS 39.1-Establishment, Modification, and Discontinuance of Interagency Fleet Management Systems § 101-39.104 Notice of establishment of a fleet management... of a fleet management system. 101-39.104 Section 101-39.104 Public Contracts and Property......

  2. 41 CFR 101-39.104 - Notice of establishment of a fleet management system.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ..., TRANSPORTATION, AND MOTOR VEHICLES 39-INTERAGENCY FLEET MANAGEMENT SYSTEMS 39.1-Establishment, Modification, and Discontinuance of Interagency Fleet Management Systems § 101-39.104 Notice of establishment of a fleet management... of a fleet management system. 101-39.104 Section 101-39.104 Public Contracts and Property......

  3. 41 CFR 101-39.104-1 - Consolidations into a fleet management system.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... fleet management system. 101-39.104-1 Section 101-39.104-1 Public Contracts and Property Management..., TRANSPORTATION, AND MOTOR VEHICLES 39-INTERAGENCY FLEET MANAGEMENT SYSTEMS 39.1-Establishment, Modification, and Discontinuance of Interagency Fleet Management Systems § 101-39.104-1 Consolidations into a fleet...

  4. Performance Improvement of Induction Motor Speed Sensor-Less Vector Control System Using an Adaptive Observer with an Estimated Flux Feedback in Low Speed Range

    NASA Astrophysics Data System (ADS)

    Fukumoto, Tetsuya; Kato, Yousuke; Kurita, Kazuya; Hayashi, Yoichi

    Because of various errors caused by dead time, temperature variation of resistance and so on, the speed estimation error is inevitable in the speed sensor-less vector control methods of the induction motor. Especially, the speed control loop becomes unstable at near zero frequency. In order to solve these problems, this paper proposes a novel design of an adaptive observer for the speed estimation. Adding a feedback loop of the error between the estimated and reference fluxes, the sensitivity of the current error signals for the speed estimation and the primary resistance identification are improved. The proposed system is analyzed and the appropriate feedback gains are derived. The experimental results showed good performance in low speed range.

  5. Fleet-Car Market PENetration Simulator: CPEN user's guide

    SciTech Connect

    Weil, R.

    1980-08-01

    The purpose of this manual is to assist prospective users in the understanding and execution of Fleet-Car Market PENetration Simulator (CPEN). CPEN is an interactive FORTRAN program whose purpose is to produce estimates of fleet-market-penetration rates of alternative passenger cars that can be described in terms of specific physical and economic attributes. The data were derived from questionnaires distributed to fleet operators affiliated with National Association of Fleet Administrators (NAFA). Besides the NAFA data, CPEN uses 48 variables that are interactively inserted. Complete data-input descriptions are included in the manual along with algorithm and application flowcharts. Examples of complete successful simulator runs are included for alternative program paths. A listing of the computer program and a glossary for CPEN are included.

  6. 33 CFR 138.90 - Individual and Fleet Certificates.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... (CONTINUED) MARINE POLLUTION FINANCIAL RESPONSIBILITY AND COMPENSATION FINANCIAL RESPONSIBILITY FOR WATER POLLUTION (VESSELS) AND OPA 90 LIMITS OF LIABILITY (VESSELS AND DEEPWATER PORTS) Financial Responsibility for Water Pollution (Vessels) § 138.90 Individual and Fleet Certificates. (a) The Director,...

  7. 33 CFR 138.90 - Individual and Fleet Certificates.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... (CONTINUED) MARINE POLLUTION FINANCIAL RESPONSIBILITY AND COMPENSATION FINANCIAL RESPONSIBILITY FOR WATER POLLUTION (VESSELS) AND OPA 90 LIMITS OF LIABILITY (VESSELS AND DEEPWATER PORTS) Financial Responsibility for Water Pollution (Vessels) § 138.90 Individual and Fleet Certificates. (a) The Director,...

  8. 33 CFR 138.90 - Individual and Fleet Certificates.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... (CONTINUED) MARINE POLLUTION FINANCIAL RESPONSIBILITY AND COMPENSATION FINANCIAL RESPONSIBILITY FOR WATER POLLUTION (VESSELS) AND OPA 90 LIMITS OF LIABILITY (VESSELS AND DEEPWATER PORTS) Financial Responsibility for Water Pollution (Vessels) § 138.90 Individual and Fleet Certificates. (a) The Director,...

  9. 33 CFR 138.90 - Individual and Fleet Certificates.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... (CONTINUED) MARINE POLLUTION FINANCIAL RESPONSIBILITY AND COMPENSATION FINANCIAL RESPONSIBILITY FOR WATER POLLUTION (VESSELS) AND OPA 90 LIMITS OF LIABILITY (VESSELS AND DEEPWATER PORTS) Financial Responsibility for Water Pollution (Vessels) § 138.90 Individual and Fleet Certificates. (a) The Director,...

  10. 33 CFR 138.90 - Individual and Fleet Certificates.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... (CONTINUED) MARINE POLLUTION FINANCIAL RESPONSIBILITY AND COMPENSATION FINANCIAL RESPONSIBILITY FOR WATER POLLUTION (VESSELS) AND OPA 90 LIMITS OF LIABILITY (VESSELS AND DEEPWATER PORTS) Financial Responsibility for Water Pollution (Vessels) § 138.90 Individual and Fleet Certificates. (a) The Director,...

  11. Phase-Based Adaptive Estimation of Magnitude-Squared Coherence Between Turbofan Internal Sensors and Far-Field Microphone Signals

    NASA Technical Reports Server (NTRS)

    Miles, Jeffrey Hilton

    2015-01-01

    A cross-power spectrum phase based adaptive technique is discussed which iteratively determines the time delay between two digitized signals that are coherent. The adaptive delay algorithm belongs to a class of algorithms that identifies a minimum of a pattern matching function. The algorithm uses a gradient technique to find the value of the adaptive delay that minimizes a cost function based in part on the slope of a linear function that fits the measured cross power spectrum phase and in part on the standard error of the curve fit. This procedure is applied to data from a Honeywell TECH977 static-engine test. Data was obtained using a combustor probe, two turbine exit probes, and far-field microphones. Signals from this instrumentation are used estimate the post-combustion residence time in the combustor. Comparison with previous studies of the post-combustion residence time validates this approach. In addition, the procedure removes the bias due to misalignment of signals in the calculation of coherence which is a first step in applying array processing methods to the magnitude squared coherence data. The procedure also provides an estimate of the cross-spectrum phase-offset.

  12. Development and Flight Testing of an Adaptable Vehicle Health-Monitoring Architecture

    NASA Technical Reports Server (NTRS)

    Woodard, Stanley E.; Coffey, Neil C.; Gonzalez, Guillermo A.; Woodman, Keith L.; Weathered, Brenton W.; Rollins, Courtney H.; Taylor, B. Douglas; Brett, Rube R.

    2003-01-01

    Development and testing of an adaptable wireless health-monitoring architecture for a vehicle fleet is presented. It has three operational levels: one or more remote data acquisition units located throughout the vehicle; a command and control unit located within the vehicle; and a terminal collection unit to collect analysis results from all vehicles. Each level is capable of performing autonomous analysis with a trained adaptable expert system. The remote data acquisition unit has an eight channel programmable digital interface that allows the user discretion for choosing type of sensors; number of sensors, sensor sampling rate, and sampling duration for each sensor. The architecture provides framework for a tributary analysis. All measurements at the lowest operational level are reduced to provide analysis results necessary to gauge changes from established baselines. These are then collected at the next level to identify any global trends or common features from the prior level. This process is repeated until the results are reduced at the highest operational level. In the framework, only analysis results are forwarded to the next level to reduce telemetry congestion. The system's remote data acquisition hardware and non-analysis software have been flight tested on the NASA Langley B757's main landing gear.

  13. A road safety performance indicator for vehicle fleet compatibility.

    PubMed

    Christoph, Michiel; Vis, Martijn Alexander; Rackliff, Lucy; Stipdonk, Henk

    2013-11-01

    This paper discusses the development and the application of a safety performance indicator which measures the intrinsic safety of a country's vehicle fleet related to fleet composition. The indicator takes into account both the 'relative severity' of individual collisions between different vehicle types, and the share of those vehicle types within a country's fleet. The relative severity is a measure for the personal damage that can be expected from a collision between two vehicles of any type, relative to that of a collision between passenger cars. It is shown how this number can be calculated using vehicle mass only. A sensitivity analysis is performed to study the dependence of the indicator on parameter values and basic assumptions made. The indicator is easy to apply and satisfies the requirements for appropriate safety performance indicators. It was developed in such a way that it specifically scores the intrinsic safety of a fleet due to its composition, without being influenced by other factors, like helmet wearing. For the sake of simplicity, and since the required data is available throughout Europe, the indicator was applied to the relative share of three of the main vehicle types: passenger cars, heavy goods vehicles and motorcycles. Using the vehicle fleet data from 13EU Member States and Norway, the indicator was used to rank the countries' safety performance. The UK was found to perform best in terms of its fleet composition (value is 1.07), while Greece has the worst performance with the highest indicator value (1.41). PMID:23953768

  14. National Federal Fleet Loaner Program, Interim Status Report

    SciTech Connect

    Francfort, James Edward

    2000-10-01

    The goal of the U.S. Department of Energy's (DOE) Loaner Program is to increase the awareness, deployment, and use of electric vehicles (EVs) in Federal fleets. The Loaner Program accomplishes this by providing free EVs to Federal fleets on a loaner basis, generally for 1 or 2 months. The Program partners DOE with six electric utilities, with DOE providing financial support and some leads on Federal fleets interested in obtaining EVs. The utilities obtain the vehicles, identify candidate loaner fleets, loan the vehicles, provide temporary charging infrastructure, provide overall support to participating Federal fleets, and support fleets with their leasing decisions. While the utilities have not had the success initially envisioned by themselves, DOE, the Edison Electric Institute, and the Electric Vehicle Association of the Americas, the utilities can not be faulted for their efforts, as they are not the entity that makes the ultimate lease or no-lease decision. Some external groups have suggested to DOE that they direct other federal agencies to change their processes to make loaning vehicles easier; this is simply not within the power of DOE. By law, a certain percentage of all new vehicle acquisitions are supposed to be alternative fuel vehicles (AFV); however, with no enforcement, the federal agencies are not compelled to lease AFVs such as electric vehicles.

  15. An on-line adaptive estimation method for water holdup measurement in oil–water two-phase flow with a conductance/capacitance sensor

    NASA Astrophysics Data System (ADS)

    Wu, Hao; Tan, Chao; Dong, Feng

    2016-07-01

    Oil–water two-phase flow widely exists in industrial processes such as petroleum engineering and chemical engineering. Accurate and real-time measurement of water holdup is an important problem requiring urgent solutions. In this work, a conductance and capacitance combination sensor (CCCS) system with four conductance rings and two concave capacitance plates was validated for its measurement performance of in situ water holdup through dynamic experiments. An online adaptive weight Kalman estimation (OAWKE) fusion algorithm for the CCCS system is proposed to fuse the conductance measurement and capacitance measurement. The algorithm has fast and dynamic response for the water holdup measurement of oil–water two-phase flow and has improved measurement precision by the adaptive data fusion method. The OAWKE fusion algorithm also has the ability to deal with the abrupt change of water holdup during the measurement process. Therefore, in the low water conductivity condition (tap water), the CCCS system with the OAWKE fusion algorithm can dynamically estimate the real-time full range water holdup of oil–water two-phase flow, which has prospects in the petroleum industry.

  16. Adaptive Multi-Path Routing with Guaranteed Target-Delivery Ratio of Critical Events in Wireless Sensor Networks

    NASA Astrophysics Data System (ADS)

    Baek, Jang Woon; Nam, Young Jin; Seo, Dae-Wha

    Wireless sensor networks are subject to node and link failures for a variety of reasons. This paper proposes a k-disjoint-path routing algorithm that varies the number of disjoint paths (k) in order to meet a target-delivery ratio of critical events and to reduce energy consumption. The proposed algorithm sends packets to the base station through a single path without the occurrence of critical events, however, it sends packets to the base station through k disjoint paths (k > 1) under the occurrence of critical events, where k is computed from a well-defined fault model. The proposed algorithm detects the occurrence of critical events by monitoring collected data patterns. The simulation results reveal that the proposed algorithm is more resilient to random node failure and patterned failure than other routing algorithms, and it also decreases energy consumption much more than the multi-path and path-repair algorithms.

  17. Mapping sub-surface geostrophic currents from altimetry and a fleet of gliders

    NASA Astrophysics Data System (ADS)

    Alvarez, A.; Chiggiato, J.; Schroeder, K.

    2013-04-01

    Integrating the observations gathered by different platforms into a unique physical picture of the environment is a fundamental aspect of networked ocean observing systems. These are constituted by a spatially distributed set of sensors and platforms that simultaneously monitor a given ocean region. Remote sensing from satellites is an integral part of present ocean observing systems. Due to their autonomy, mobility and controllability, underwater gliders are envisioned to play a significant role in the development of networked ocean observatories. Exploiting synergism between remote sensing and underwater gliders is expected to result on a better characterization of the marine environment than using these observational sources individually. This study investigates a methodology to estimate the three dimensional distribution of geostrophic currents resulting from merging satellite altimetry and in situ samples gathered by a fleet of Slocum gliders. Specifically, the approach computes the volumetric or three dimensional distribution of absolute dynamic height (ADH) that minimizes the total energy of the system while being close to in situ observations and matching the absolute dynamic topography (ADT) observed from satellite at the sea surface. A three dimensional finite element technique is employed to solve the minimization problem. The methodology is validated making use of the dataset collected during the field experiment called Rapid Environmental Picture-2010 (REP-10) carried out by the NATO Undersea Research Center-NURC during August 2010. A marine region off-shore La Spezia (northwest coast of Italy) was sampled by a fleet of three coastal Slocum gliders. Results indicate that the geostrophic current field estimated from gliders and altimetry significantly improves the estimates obtained using only the data gathered by the glider fleet.

  18. Precision of FLEET Velocimetry Using High-speed CMOS Camera Systems

    NASA Technical Reports Server (NTRS)

    Peters, Christopher J.; Danehy, Paul M.; Bathel, Brett F.; Jiang, Naibo; Calvert, Nathan D.; Miles, Richard B.

    2015-01-01

    Femtosecond laser electronic excitation tagging (FLEET) is an optical measurement technique that permits quantitative velocimetry of unseeded air or nitrogen using a single laser and a single camera. In this paper, we seek to determine the fundamental precision of the FLEET technique using high-speed complementary metal-oxide semiconductor (CMOS) cameras. Also, we compare the performance of several different high-speed CMOS camera systems for acquiring FLEET velocimetry data in air and nitrogen free-jet flows. The precision was defined as the standard deviation of a set of several hundred single-shot velocity measurements. Methods of enhancing the precision of the measurement were explored such as digital binning (similar in concept to on-sensor binning, but done in post-processing), row-wise digital binning of the signal in adjacent pixels and increasing the time delay between successive exposures. These techniques generally improved precision; however, binning provided the greatest improvement to the un-intensified camera systems which had low signal-to-noise ratio. When binning row-wise by 8 pixels (about the thickness of the tagged region) and using an inter-frame delay of 65 micro sec, precisions of 0.5 m/s in air and 0.2 m/s in nitrogen were achieved. The camera comparison included a pco.dimax HD, a LaVision Imager scientific CMOS (sCMOS) and a Photron FASTCAM SA-X2, along with a two-stage LaVision High Speed IRO intensifier. Excluding the LaVision Imager sCMOS, the cameras were tested with and without intensification and with both short and long inter-frame delays. Use of intensification and longer inter-frame delay generally improved precision. Overall, the Photron FASTCAM SA-X2 exhibited the best performance in terms of greatest precision and highest signal-to-noise ratio primarily because it had the largest pixels.

  19. Precision of FLEET Velocimetry Using High-Speed CMOS Camera Systems

    NASA Technical Reports Server (NTRS)

    Peters, Christopher J.; Danehy, Paul M.; Bathel, Brett F.; Jiang, Naibo; Calvert, Nathan D.; Miles, Richard B.

    2015-01-01

    Femtosecond laser electronic excitation tagging (FLEET) is an optical measurement technique that permits quantitative velocimetry of unseeded air or nitrogen using a single laser and a single camera. In this paper, we seek to determine the fundamental precision of the FLEET technique using high-speed complementary metal-oxide semiconductor (CMOS) cameras. Also, we compare the performance of several different high-speed CMOS camera systems for acquiring FLEET velocimetry data in air and nitrogen free-jet flows. The precision was defined as the standard deviation of a set of several hundred single-shot velocity measurements. Methods of enhancing the precision of the measurement were explored such as digital binning (similar in concept to on-sensor binning, but done in post-processing), row-wise digital binning of the signal in adjacent pixels and increasing the time delay between successive exposures. These techniques generally improved precision; however, binning provided the greatest improvement to the un-intensified camera systems which had low signal-to-noise ratio. When binning row-wise by 8 pixels (about the thickness of the tagged region) and using an inter-frame delay of 65 microseconds, precisions of 0.5 meters per second in air and 0.2 meters per second in nitrogen were achieved. The camera comparison included a pco.dimax HD, a LaVision Imager scientific CMOS (sCMOS) and a Photron FASTCAM SA-X2, along with a two-stage LaVision HighSpeed IRO intensifier. Excluding the LaVision Imager sCMOS, the cameras were tested with and without intensification and with both short and long inter-frame delays. Use of intensification and longer inter-frame delay generally improved precision. Overall, the Photron FASTCAM SA-X2 exhibited the best performance in terms of greatest precision and highest signal-to-noise ratio primarily because it had the largest pixels.

  20. The Future of the USCG Icebreaker Fleet

    NASA Astrophysics Data System (ADS)

    Edwards, M. H.; Prince, M.

    2004-12-01

    The United States Coast Guard (USCG) operates three icebreakers to support science in polar regions: the USCGC HEALY (WAGB-20), the USCGC POLAR STAR (WABG-10) and the USCGC POLAR SEA (WAGB-11). USCGC HEALY, the youngest of the icebreakers, has successfully completed four field seasons in the Arctic Ocean and one deployment to Antarctica since the ship was delivered in late 1999. Operations on board HEALY have improved with each deployment thanks to the feedback provided by science users and the responsiveness of USCG personnel to suggestions for enhancing shipboard support of data and sample acquisition. The POLAR-class icebreakers have been used primarily to support Deep Freeze by carrying supplies to McMurdo Station in Antarctica. Unfortunately, both POLAR STAR and SEA are approaching the end of their useful service life. The main propulsion system of the POLAR SEA has recently been declared unfit to support another trip to Antarctica until at least the 2007 field season, which places an additional burden on the already ailing POLAR STAR and potentially impacts the arctic science schedule of HEALY. The Arctic Icebreaker Coordinating Committee (AICC), which was initially formed to oversee the design and building of the USCGC Healy, now works to liaise and facilitate communications between scientists, funding agencies and facility providers and assist with the planning of polar science projects. Incumbent in this is the requirement that AICC provide continuing oversight for scientific aspects of the potential refitting or replacement of POLAR STAR and POLAR SEA as well as HEALY's scientific spaces and outfitting. The purpose of this presentation is to provide the polar science community with the most recent information about the status of the USCG icebreaker fleet and to solicit, synthesize and present the needs of the community to the Coast Guard to facilitate efficient and effective utilization of U.S. icebreakers.

  1. Chemical sensors

    SciTech Connect

    Janata, J.; Josowicz, M.; DeVaney, D.M. )

    1994-06-15

    This review of chemical sensors contains the following topics of interest: books and reviews; reviews of sensors by their type; fabrication and selectivity; data processing; thermal sensors; mass sensors (fabrication, gas sensors, and liquid sensors); electrochemical sensors (potentiometric sensors, amperometric sensors, and conductometric sensors); and optical sensors (fabrication, liquid sensors, biosensors, and gas sensors). 795 refs., 1 tab.

  2. Adaptation of frequency-domain readout for Transition Edge Sensor bolometers for the POLARBEAR-2 Cosmic Microwave Background experiment

    NASA Astrophysics Data System (ADS)

    Hattori, Kaori; Arnold, Kam; Barron, Darcy; Dobbs, Matt; de Haan, Tijmen; Harrington, Nicholas; Hasegawa, Masaya; Hazumi, Masashi; Holzapfel, William L.; Keating, Brian; Lee, Adrian T.; Morii, Hideki; Myers, Michael J.; Smecher, Graeme; Suzuki, Aritoki; Tomaru, Takayuki

    2013-12-01

    The POLARBEAR-2 Cosmic Microwave Background (CMB) experiment aims to observe B-mode polarization with high sensitivity to explore gravitational lensing of CMB and inflationary gravitational waves. POLARBEAR-2 is an upgraded experiment based on POLARBEAR-1, which had first light in January 2012. For POLARBEAR-2, we will build a receiver that has 7588 Transition Edge Sensor (TES) bolometers coupled to two-band (95 and 150 GHz) polarization-sensitive antennas. For the large array's readout, we employ digital frequency-domain multiplexing and multiplex 32 bolometers through a single superconducting quantum interference device (SQUID). An 8-bolometer frequency-domain multiplexing readout has been deployed with the POLARBEAR-1 experiment. Extending that architecture to 32 bolometers requires an increase in the bandwidth of the SQUID electronics to 3 MHz. To achieve this increase in bandwidth, we use Digital Active Nulling (DAN) on the digital frequency multiplexing platform. In this paper, we present requirements and improvements on parasitic inductance and resistance of cryogenic wiring and capacitors used for modulating bolometers. These components are problematic above 1 MHz. We also show that our system is able to bias a bolometer in its superconducting transition at 3 MHz.

  3. Lyot-based low order wavefront sensor: implementation on the Subaru Coronagraphic Extreme Adaptive Optics System and its laboratory performance

    NASA Astrophysics Data System (ADS)

    Singh, Garima; Guyon, Olivier; Baudoz, Pierre; Jovanovich, Nemanja; Martinache, Frantz; Kudo, Tomoyuki; Serabyn, Eugene; Kuhn, Jonas G.

    2014-08-01

    High throughput, low inner working angle (IWA) phase masks coronagraphs are essential to directly image and characterize (via spectroscopy) earth-like planets. However, the performance of low-IWA coronagraphs is limited by residual pointing errors and other low-order modes. The extent to which wavefront aberrations upstream of the coronagraph are corrected and calibrated drives coronagraphic performance. Addressing this issue is essential for preventing coronagraphic leaks, thus we have developed a Lyot-based low order wave front sensor (LLOWFS) to control the wavefront aberrations in a coronagraph. The LLOWFS monitors the starlight rejected by the coronagraphic mask using a reflective Lyot stop in the downstream pupil plane. The early implementation of LLOWFS at LESIA, Observatoire de Paris demonstrated an open loop measurement accuracy of 0.01 λ/D for tip-tilt at 638 nm when used in conjunction with a four quadrant phase mask (FQPM) in the laboratory. To further demonstrate our concept, we have installed the reflective Lyot stops on the Subaru Coronagraphic Extreme AO (SCExAO) system at the Subaru Telescope and modified the system to support small IWA phase mask coronagraphs (< 1λ/D) on-sky such as FQPM, eight octant phase mask, vector vortex coronagraph and the phase induced amplitude apodization complex phase mask coronagraph with a goal of obtaining milli arc-second pointing accuracy. Laboratory results have shown the measurement of tip, tilt, focus, oblique and right astigmatism at 1.55 μm for the vector vortex coronagraph. Our initial on-sky result demonstrate the closed loop accuracy of < 7 x 10-3 λ/D at 1.6 μm for tip, tilt and focus aberrations with the vector vortex coronagraph.

  4. Moving forward in plant food safety and security through NanoBioSensors: Adopt or adapt biomedical technologies?

    PubMed

    Sharma, Tarun K; Ramanathan, Rajesh; Rakwal, Randeep; Agrawal, Ganesh K; Bansal, Vipul

    2015-05-01

    Plant-based foods are integral part of our day-to-day diet. Increasing world population has put forth an ever increasing demand for plant-based foods, and food security remains a major concern. Similarly, biological, chemical, and physical threats to our food and increasing regulatory demands to control the presence of foreign species in food products have made food safety a growing issue. Nanotechnology has already established its roots in diverse disciplines. However, the food industry is yet to harness the full potential of the unique capabilities offered by this next-generation technology. While there might be safety concerns in regards to integration of nanoproducts with our food products, an aspect of nanotechnology that can make remarkable contribution to different elements of the food chain is the use of nanobiosensors and diagnostic platforms for monitoring food traceability, quality, safety, and nutritional value. This brings us to an important question that whether existing diagnostic platforms that have already been well developed for biomedical and clinical application are suitable for food industry or whether the demands of the food industry are altogether different that may not allow adoption/adaptation of the existing technology. This review is an effort to raise this important "uncomfortable" yet "timely" question. PMID:25727733

  5. Integrated operations/payloads/fleet analysis. Volume 1: Summary, study overview

    NASA Technical Reports Server (NTRS)

    1971-01-01

    The preparation of payload input data for analysis, and the capture and cost analyses are described for the current fleet, a low cost expendable fleet, and the space shuttle/space tug fleet. The data preparation consisted of formatting, extending, and correcting the input data which were broken down in terms of satellite gross weight. The results of the analyses indicate a significant reduction in the required total number of new payload units for the space shuttle/space tug fleet. Another result is that 26% of the payloads for the new low cost expendable fleet and 26% for the space shuttle/space tug fleet are of low cost payload designs.

  6. Evaluation of Gear Condition Indicator Performance on Rotorcraft Fleet

    NASA Technical Reports Server (NTRS)

    Antolick, Lance J.; Branning, Jeremy S.; Wade, Daniel R.; Dempsey, Paula J.

    2010-01-01

    The U.S. Army is currently expanding its fleet of Health Usage Monitoring Systems (HUMS) equipped aircraft at significant rates, to now include over 1,000 rotorcraft. Two different on-board HUMS, the Honeywell Modern Signal Processing Unit (MSPU) and the Goodrich Integrated Vehicle Health Management System (IVHMS), are collecting vibration health data on aircraft that include the Apache, Blackhawk, Chinook, and Kiowa Warrior. The objective of this paper is to recommend the most effective gear condition indicators for fleet use based on both a theoretical foundation and field data. Gear diagnostics with better performance will be recommended based on both a theoretical foundation and results of in-fleet use. In order to evaluate the gear condition indicator performance on rotorcraft fleets, results of more than five years of health monitoring for gear faults in the entire HUMS equipped Army helicopter fleet will be presented. More than ten examples of gear faults indicated by the gear CI have been compiled and each reviewed for accuracy. False alarms indications will also be discussed. Performance data from test rigs and seeded fault tests will also be presented. The results of the fleet analysis will be discussed, and a performance metric assigned to each of the competing algorithms. Gear fault diagnostic algorithms that are compliant with ADS-79A will be recommended for future use and development. The performance of gear algorithms used in the commercial units and the effectiveness of the gear CI as a fault identifier will be assessed using the criteria outlined in the standards in ADS-79A-HDBK, an Army handbook that outlines the conversion from Reliability Centered Maintenance to the On-Condition status of Condition Based Maintenance.

  7. [Rate of injuries in military men of the North Fleet].

    PubMed

    Khankevich, Iu R; Myznikov, I L; Askerko, I V; Sil'chenko, E S; Matochkina, A A

    2012-07-01

    Statistics of the rate of injuries in military men of the North Fleet during 2002-2010 is analyzed. Over the specified period rate of injuries, poisonings and consequences of influence of other external actions was 30,06% among the conscripts, 30,23% among the contract military men. The authors analyzed reasons and circumstances of injuries, prevention measures, and orgnisation of military physician expertise and indemnity insurance for the military men injured during the service. Ways of improvement of the system of injury prevention on the North Fleet are suggested. PMID:23038958

  8. NASA space transportation plans and roles of a mixed fleet

    NASA Technical Reports Server (NTRS)

    Branscome, Darrell R.

    1987-01-01

    An account is given of the results of a September, 1987 NASA 'mixed fleet' launching resources/scheduling study that predicated capability projections on a fleet of available ELVs. The launch capability projections extended as far as 1995, and in their later phases encompassed the resumption of Space Shuttle operations and the availability of Orbital Maneuvering Vehicle, which could accomplish such things as the reboosting of the Hubble Space Telescope in 1991, and even the Shuttle-Derived Vehicle, of which two distinct concepts are presently being considered; both would heavily rely on Space Shuttle hardware, but would be unmanned.

  9. Fleet management based on satellite positioning and communication

    NASA Astrophysics Data System (ADS)

    Hossfeld, Bernd

    1992-07-01

    Computerized systems for vehicle location, communication and fleet management provide permanent and direct on route access to the fleet. Thus time schedules, routes and cargo assignments can be optimized. Transport hazards can be identifed and minimized or avoided. The functionality of such a system is based on the following matched components: sufficiently accurate positioning of each vehicle based on GPS (Global Positioning System); communication system, functioning no matter what the position of the vehicle is via Inmarsat; centralized, computer based management system, which will keep the dispatcher free from routine tasks, provide hints for decision finding in tactical situations, enables access and control based on a digital map information system.

  10. The use of GPS for automatic vehicle location and fleet management - A reliable and economic system for the 90's

    NASA Astrophysics Data System (ADS)

    Denaro, Robert P.

    1991-01-01

    This paper offers an approach to an integrated automatic vehicle location (AVL) system that integrates GPS with communications links, auxiliary dead reckoning sensors, and modern workstation implementation of a control and location monitoring center. The actual implementation of this AVL system in a municipal bus operation is described, along with other fleet management applications. Then, further details are provided on Trimble's development of the AVL system that uses a deep integration where the dead reckoning subsystem is continually calibrated by the GPS measurements when GPS is available; then the dead reckoning continues alone with newly calibrated drift parameters when the GPS signal is interrupted.

  11. [Gil Eannes--the hospital ship of the Portuguese fishing fleet].

    PubMed

    Ramos, Samuel; Doria, José Luís; Pina, Madalena Esperança

    2008-06-01

    The history of Portuguese hospital-ships dates back to the fleets in the era of the Great Discoveries. In 1916, during the First World War, the Allies appealed to Portugal to act as a neutral country. All the German ships on the river Tagus were impounded and adapted for tasks related to the war. The Hanseatic line vessel Lahneck had its name changed to Gil Eannes and was modified for troop transport and to give assistance to fishing boats. Many years later, when the old Gil Eanes came to the end of its life and needed to be replaced, a new ship was built in the Viana do Castelo shipyard, using up-to-date designs for a hospital-ship. The new ship was launched in 1955, mainly to assist the Portuguese cod fish fleet, working in the seas around Newfoundland. More recently, it has returned to Viana do Castelo docks and, after restoration, has been transformed into a nautical museum and a student residence, to keep alive the memories of this traditional Portuguese fishermen's activity. PMID:19579337

  12. Rolling Deck to Repository (R2R): Building a Reference Cruise Catalog for the Research Fleet

    NASA Astrophysics Data System (ADS)

    Arko, R. A.; Clark, P. D.; Chandler, C. L.; Smith, S. R.

    2012-12-01

    The Rolling Deck to Repository (R2R) program is developing infrastructure to ensure the underway sensor data from NSF-supported oceanographic research vessels are routinely and consistently documented, preserved in long-term archives, and disseminated to the science community. A core element of this infrastructure is a master catalog of research vessels, cruises, sensor systems, underway datasets, navigation products, field reports, event logs, file formats, people, organizations, and funding awards that is maintained uniformly across the research fleet. All NSF-supported vessel operators now submit their underway cruise data and documentation directly to R2R, per the revised Division of Ocean Sciences (OCE) Sample and Data Policy published in 2011. R2R ingests this content into the fleet catalog, assigning globally unique and persistent identifiers at the cruise, dataset, and file (granule) levels. The catalog is aligned with community-standard vocabularies, working collaboratively with the NOAA Data Centers, UNOLS Office, and pan-European SeaDataNet project; and includes links to related data at other inter/national repositories. In response to community demand, we are extending the catalog to include instrument-specific metadata such as installation details, patch tests, and calibration results. The entire R2R catalog is published on the Web as "Linked Data", making it easily accessible to encourage integration with other repositories. Selected content is also published in formal metadata records according to ISO and W3C standards, suitable for submission to long-term archives. We are deploying both faceted (classification/filter) and Web map-based browse and search interfaces.

  13. Federal Fleet Files, FEMP, Vol. 1, No. 2 - June 2009 (Fact Sheet)

    SciTech Connect

    Not Available

    2009-06-01

    June 2009 issue of the FEMP Federal Fleet Files monthly newsletter for the FEMP Federal Fleet Program that outlines vehicle, alternative fuel, infrastructure, and management strategy updates to Federal agencies.

  14. 76 FR 1521 - Security Zone: Fleet Industrial Supply Center Pier, San Diego, CA

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-01-11

    ... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA87 Security Zone: Fleet Industrial Supply Center Pier, San... Fleet Industrial Supply Center Pier. The pier is no longer owned by the U.S. Navy and the existing... of the San Diego Bay, San Diego, CA. The existing security zone is around the former Fleet...

  15. 75 FR 20778 - Security Zone; Portland Rose Festival Fleet Week, Willamette River, Portland, OR

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-21

    ... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA87 Security Zone; Portland Rose Festival Fleet Week... Hawthorne and Steel Bridges in Portland, Oregon during the Portland Rose Festival Fleet Week from June 2... Rose Festival Fleet Week, and there is insufficient time to publish a notice of proposed...

  16. 41 CFR 102-34.55 - Are there fleet average fuel economy standards we must meet?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 41 Public Contracts and Property Management 3 2010-07-01 2010-07-01 false Are there fleet average... PROPERTY 34-MOTOR VEHICLE MANAGEMENT Obtaining Fuel Efficient Motor Vehicles § 102-34.55 Are there fleet... that each executive agency meet the fleet average fuel economy standards in place as of January 1...

  17. 49 CFR 526.3 - Transfer of vehicle from non-domestic to domestic fleet.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... fleet. 526.3 Section 526.3 Transportation Other Regulations Relating to Transportation (Continued... domestic fleet. Each plan submitted under section 503(b)(4) of the Motor Vehicle Information and Cost... fleet under the plan (i.e., those with at least 50 percent but less than 75 percent U.S. or...

  18. 75 FR 45055 - Security Zone; 2010 Seattle Seafair Fleet Week Moving Vessels, Puget Sound, WA

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-02

    ... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA87 Security Zone; 2010 Seattle Seafair Fleet Week Moving... acts during Seafair Fleet Week and will do so by prohibiting any person or vessel from entering or... of visiting foreign vessels in the 2010 Seattle Seafair Fleet Week event. Basis and Purpose...

  19. 41 CFR 101-39.105-1 - Transfers from discontinued or curtailed fleet management systems.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... discontinued or curtailed fleet management systems. 101-39.105-1 Section 101-39.105-1 Public Contracts and... AVIATION, TRANSPORTATION, AND MOTOR VEHICLES 39-INTERAGENCY FLEET MANAGEMENT SYSTEMS 39.1-Establishment, Modification, and Discontinuance of Interagency Fleet Management Systems § 101-39.105-1 Transfers...

  20. 77 FR 44475 - Security Zones; Seattle's Seafair Fleet Week Moving Vessels, Puget Sound, WA

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-07-30

    ... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA87 Security Zones; Seattle's Seafair Fleet Week Moving...: The Coast Guard will enforce Seattle's Seafair Fleet Week Moving Vessels Security Zones from 12:00 p.m... ensure the security of the vessels from sabotage or other subversive acts during Seafair Fleet...

  1. 40 CFR 88.308-94 - Programmatic requirements for clean-fuel fleet vehicles.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...-fuel fleet vehicles. 88.308-94 Section 88.308-94 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) CLEAN-FUEL VEHICLES Clean-Fuel Fleet Program § 88.308-94 Programmatic requirements for clean-fuel fleet vehicles. (a) Multi-State nonattainment areas. The...

  2. 77 FR 57494 - Safety Zone; Fleet Week Fireworks, San Francisco Bay, San Francisco, CA

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-09-18

    ... SECURITY Coast Guard 33 CFR Part 165 Safety Zone; Fleet Week Fireworks, San Francisco Bay, San Francisco... will enforce the safety zone for the Fleet Week Fireworks in the Captain of the Port, San Francisco...'' W (NAD83) for the Fleet Week Fireworks in 33 CFR 165.1191, Table 1, item number 25. This safety...

  3. 33 CFR 162.270 - Restricted areas in vicinity of Maritime Administration Reserve Fleets.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Maritime Administration Reserve Fleets. 162.270 Section 162.270 Navigation and Navigable Waters COAST GUARD... REGULATIONS § 162.270 Restricted areas in vicinity of Maritime Administration Reserve Fleets. (a) The... National Defense Reserve Fleets of the Maritime Administration, Department of Transportation: (1)...

  4. 78 FR 72070 - Notice of Availability of Record of Decision for Atlantic Fleet Training and Testing

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-12-02

    ... Department of the Navy Notice of Availability of Record of Decision for Atlantic Fleet Training and Testing... Atlantic Fleet study area as described in Alternative 2 for the proposed action. Under Alternative 2, the... for Atlantic Fleet Training and Testing, dated August 2013 and supporting documents. Single copies...

  5. 41 CFR 102-34.300 - How do we dispose of a domestic fleet motor vehicle?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... domestic fleet motor vehicle? 102-34.300 Section 102-34.300 Public Contracts and Property Management... fleet motor vehicle? After meeting the replacement standards under subpart E of this part, you may dispose of a Government-owned domestic fleet motor vehicle. Detailed instructions for the transfer of...

  6. 77 FR 35862 - Safety Zone; Fleet Week Maritime Festival, Pier 66 Elliott Bay, Seattle, WA

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-15

    ... SECURITY Coast Guard 33 CFR Part 165 Safety Zone; Fleet Week Maritime Festival, Pier 66 Elliott Bay... Guard will enforce the Fleet Week Maritime Festival's Pier 66 Safety Zone in Elliott Bay, WA from 8 a.m... Guard will enforce the Safety Zone for the Fleet Week Maritime Festival in 33 CFR 165.1330 on August...

  7. 76 FR 40617 - Security Zone; 2011 Seattle Seafair Fleet Week Moving Vessels, Puget Sound, Washington

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-11

    ... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA87 Security Zone; 2011 Seattle Seafair Fleet Week Moving... while each vessel is participating in the Seafair Fleet Week Parade of Ships and while moored following... security of the vessels from sabotage or other subversive acts during Seafair Fleet Week Parade of...

  8. 47 CFR 80.55 - Application for a fleet station license.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false Application for a fleet station license. 80.55... SERVICES STATIONS IN THE MARITIME SERVICES Applications and Licenses § 80.55 Application for a fleet... different vessels on the same application. Under these circumstances a fleet station license may be...

  9. 77 FR 75257 - Proposed Collection of Information: Medium- and Heavy-Duty Truck Fleet Survey

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-12-19

    ... Truck Fleet Survey AGENCY: National Highway Traffic Safety Administration (NHTSA), Department of... medium- and heavy-duty truck fleet managers. DATES: Comments must be received within 60 days of...- and Heavy-Duty Truck Fleet Survey. Background: The Energy Independence and Security Act...

  10. 40 CFR 80.60 - Test fleet requirements for exhaust emission testing.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 16 2010-07-01 2010-07-01 false Test fleet requirements for exhaust... fleet requirements for exhaust emission testing. (a) Candidate vehicles which conform to the emission... the in-use fleet and tested in their as-received condition. (b) Candidate vehicles for the test...

  11. 40 CFR 88.304-94 - Clean-fuel Fleet Vehicle Credit Program.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... contained in 40 CFR part 88, subpart A. (b) Program administration. (1)(i) Each state in which there is all... covered area, a dual-fuel/flexible-fuel vehicle which a fleet owner purchases to comply with covered fleet... the fleet owner receives credit for a dual-fuel/flexible-fuel vehicle purchase, the vehicle must...

  12. 41 CFR 101-39.105-1 - Transfers from discontinued or curtailed fleet management systems.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... AVIATION, TRANSPORTATION, AND MOTOR VEHICLES 39-INTERAGENCY FLEET MANAGEMENT SYSTEMS 39.1-Establishment, Modification, and Discontinuance of Interagency Fleet Management Systems § 101-39.105-1 Transfers from... discontinued or curtailed fleet management systems. 101-39.105-1 Section 101-39.105-1 Public Contracts...

  13. 41 CFR 101-39.105-1 - Transfers from discontinued or curtailed fleet management systems.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... AVIATION, TRANSPORTATION, AND MOTOR VEHICLES 39-INTERAGENCY FLEET MANAGEMENT SYSTEMS 39.1-Establishment, Modification, and Discontinuance of Interagency Fleet Management Systems § 101-39.105-1 Transfers from... discontinued or curtailed fleet management systems. 101-39.105-1 Section 101-39.105-1 Public Contracts...

  14. 41 CFR 101-39.104-1 - Consolidations into a fleet management system.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ..., TRANSPORTATION, AND MOTOR VEHICLES 39-INTERAGENCY FLEET MANAGEMENT SYSTEMS 39.1-Establishment, Modification, and... the fleet management system. Those vehicles specifically exempt by: (1) Section 101-39.106 and § 101... of Government-owned motor vehicles to the control and responsibility of the fleet management...

  15. 41 CFR 101-39.105-1 - Transfers from discontinued or curtailed fleet management systems.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... AVIATION, TRANSPORTATION, AND MOTOR VEHICLES 39-INTERAGENCY FLEET MANAGEMENT SYSTEMS 39.1-Establishment, Modification, and Discontinuance of Interagency Fleet Management Systems § 101-39.105-1 Transfers from... discontinued or curtailed fleet management systems. 101-39.105-1 Section 101-39.105-1 Public Contracts...

  16. 41 CFR 101-39.104-1 - Consolidations into a fleet management system.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ..., TRANSPORTATION, AND MOTOR VEHICLES 39-INTERAGENCY FLEET MANAGEMENT SYSTEMS 39.1-Establishment, Modification, and... the fleet management system. Those vehicles specifically exempt by: (1) Section 101-39.106 and § 101... of Government-owned motor vehicles to the control and responsibility of the fleet management...

  17. 40 CFR 88.310-94 - Applicability to covered Federal fleets.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    .... 88.310-94 Section 88.310-94 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) CLEAN-FUEL VEHICLES Clean-Fuel Fleet Program § 88.310-94 Applicability to covered Federal fleets. (a) Compliance by Federal vehicles. As per section 258(a) of the Act, fleets owned...

  18. 41 CFR 101-39.104-1 - Consolidations into a fleet management system.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ..., TRANSPORTATION, AND MOTOR VEHICLES 39-INTERAGENCY FLEET MANAGEMENT SYSTEMS 39.1-Establishment, Modification, and... the fleet management system. Those vehicles specifically exempt by: (1) Section 101-39.106 and § 101... of Government-owned motor vehicles to the control and responsibility of the fleet management...

  19. 41 CFR 102-34.340 - Do we need a fleet management information system?

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... management information system? 102-34.340 Section 102-34.340 Public Contracts and Property Management Federal... VEHICLE MANAGEMENT Federal Fleet Report § 102-34.340 Do we need a fleet management information system? Yes, you must have a fleet management information system at the department or agency level that —...

  20. Using fleets of electric-drive vehicles for grid support

    NASA Astrophysics Data System (ADS)

    Tomić, Jasna; Kempton, Willett

    Electric-drive vehicles can provide power to the electric grid when they are parked (vehicle-to-grid power). We evaluated the economic potential of two utility-owned fleets of battery-electric vehicles to provide power for a specific electricity market, regulation, in four US regional regulation services markets. The two battery-electric fleet cases are: (a) 100 Th!nk City vehicle and (b) 252 Toyota RAV4. Important variables are: (a) the market value of regulation services, (b) the power capacity (kW) of the electrical connections and wiring, and (c) the energy capacity (kWh) of the vehicle's battery. With a few exceptions when the annual market value of regulation was low, we find that vehicle-to-grid power for regulation services is profitable across all four markets analyzed. Assuming now more than current Level 2 charging infrastructure (6.6 kW) the annual net profit for the Th!nk City fleet is from US 7000 to 70,000 providing regulation down only. For the RAV4 fleet the annual net profit ranges from US 24,000 to 260,000 providing regulation down and up. Vehicle-to-grid power could provide a significant revenue stream that would improve the economics of grid-connected electric-drive vehicles and further encourage their adoption. It would also improve the stability of the electrical grid.

  1. JSC Case Study: Fleet Experience with E-85 Fuel

    NASA Technical Reports Server (NTRS)

    Hummel, Kirck

    2009-01-01

    JSC has used E-85 as part of an overall strategy to comply with Presidential Executive Order 13423 and the Energy Policy Act. As a Federal fleet, we are required to reduce our petroleum consumption by 2 percent per year, and increase the use of alternative fuels in our vehicles. With the opening of our onsite dispenser in October 2004, JSC became the second federal fleet in Texas and the fifth NASA center to add E-85 fueling capability. JSC has a relatively small number of GSA Flex Fuel fleet vehicles at the present time (we don't include personal vehicles, or other contractor's non-GSA fleet), and there were no reasonably available retail E-85 fuel stations within a 15-minute drive or within five miles (one way). So we decided to install a small 1000 gallon onsite tank and dispenser. It was difficult to obtain a supplier due to our low monthly fuel consumption, and our fuel supplier contract has changed three times in less than five years. We experiences a couple of fuel contamination and quality control issues. JSC obtained good information on E-85 from the National Ethanol Vehicle Coalition (NEVC). We also spoke with Defense Energy Support Center, (DESC), Lawrence Berkeley Laboratory, and US Army Fort Leonard Wood. E-85 is a liquid fuel that is dispensed into our Flexible Fuel Vehicles identically to regular gasoline, so it was easy for our vehicle drivers to make the transition.

  2. SuperShuttle CNG Fleet Evaluation--Final Report

    SciTech Connect

    Eudy, L.

    2000-12-07

    The mission of the US Department of Energy's Office of Transportation Technologies is to promote the development and deployment of transportation technologies that reduce US dependence on foreign oil, while helping to improve the nation's air quality and promoting US competitiveness. In support of this mission, DOE has directed the National Renewable Energy Laboratory to conduct projects to evaluate the performance and acceptability of alternative fuel vehicles. NREL has undertaken several fleet study projects, which seek to provide objective real-world fleet experiences with AFVs. For this type of study we collect, analyze, and report on operational, cost, emissions, and performance data from AFVs being driven in a fleet application. The primary purpose of such studies is to make real-world information on AFVs available to fleet managers and other potential AFV purchasers. For this project, data was collected from 13 passenger vans operating in the Boulder/Denver, Colorado area. The study vehicles were all 1999 Ford E-350 passenger vans based at SuperShuttle's Boulder location. Five of the vans were dedicated CNG, five were bi-fuel CNG/gasoline, and three were standard gasoline vans that were used for comparison.

  3. 46 CFR 296.21 - Participating Fleet Vessels.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 8 2013-10-01 2013-10-01 false Participating Fleet Vessels. 296.21 Section 296.21 Shipping MARITIME ADMINISTRATION, DEPARTMENT OF TRANSPORTATION REGULATIONS AFFECTING SUBSIDIZED VESSELS AND... Vessels. (a) Priority. To the extent that appropriated funds are available after applying the...

  4. 46 CFR 296.21 - Participating Fleet Vessels.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 8 2011-10-01 2011-10-01 false Participating Fleet Vessels. 296.21 Section 296.21 Shipping MARITIME ADMINISTRATION, DEPARTMENT OF TRANSPORTATION REGULATIONS AFFECTING SUBSIDIZED VESSELS AND... Vessels. (a) Priority. To the extent that appropriated funds are available after applying the...

  5. 48 CFR 970.2307-1 - Motor vehicle fleet operations.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... of products with recycled content to be procured pursuant to the clause at 48 CFR 970.5223-2. Section... SUPPLEMENTARY REGULATIONS DOE MANAGEMENT AND OPERATING CONTRACTS Environment, Energy and Water Efficiency... that the Federal motor vehicle fleet will serve as an example and provide a leadership role in...

  6. The NavTrax fleet management system

    NASA Astrophysics Data System (ADS)

    McLellan, James F.; Krakiwsky, Edward J.; Schleppe, John B.; Knapp, Paul L.

    The NavTrax System, a dispatch-type automatic vehicle location and navigation system, is discussed. Attention is given to its positioning, communication, digital mapping, and dispatch center components. The positioning module is a robust GPS (Global Positioning System)-based system integrated with dead reckoning devices by a decentralized-federated filter, making the module fault tolerant. The error behavior and characteristics of GPS, rate gyro, compass, and odometer sensors are discussed. The communications module, as presently configured, utilizes UHF radio technology, and plans are being made to employ a digital cellular telephone system. Polling and automatic smart vehicle reporting are also discussed. The digital mapping component is an intelligent digital single line road network database stored in vector form with full connectivity and address ranges. A limited form of map matching is performed for the purposes of positioning, but its main purpose is to define location once position is determined.

  7. Adaptive Space Structures

    NASA Technical Reports Server (NTRS)

    Wada, B.

    1993-01-01

    The term adaptive structures refers to a structural control approach in which sensors, actuators, electronics, materials, structures, structural concepts, and system-performance-validation strategies are integrated to achieve specific objectives.

  8. On-Board Mining in the Sensor Web

    NASA Astrophysics Data System (ADS)

    Tanner, S.; Conover, H.; Graves, S.; Ramachandran, R.; Rushing, J.

    2004-12-01

    On-board data mining can contribute to many research and engineering applications, including natural hazard detection and prediction, intelligent sensor control, and the generation of customized data products for direct distribution to users. The ability to mine sensor data in real time can also be a critical component of autonomous operations, supporting deep space missions, unmanned aerial and ground-based vehicles (UAVs, UGVs), and a wide range of sensor meshes, webs and grids. On-board processing is expected to play a significant role in the next generation of NASA, Homeland Security, Department of Defense and civilian programs, providing for greater flexibility and versatility in measurements of physical systems. In addition, the use of UAV and UGV systems is increasing in military, emergency response and industrial applications. As research into the autonomy of these vehicles progresses, especially in fleet or web configurations, the applicability of on-board data mining is expected to increase significantly. Data mining in real time on board sensor platforms presents unique challenges. Most notably, the data to be mined is a continuous stream, rather than a fixed store such as a database. This means that the data mining algorithms must be modified to make only a single pass through the data. In addition, the on-board environment requires real time processing with limited computing resources, thus the algorithms must use fixed and relatively small amounts of processing time and memory. The University of Alabama in Huntsville is developing an innovative processing framework for the on-board data and information environment. The Environment for On-Board Processing (EVE) and the Adaptive On-board Data Processing (AODP) projects serve as proofs-of-concept of advanced information systems for remote sensing platforms. The EVE real-time processing infrastructure will upload, schedule and control the execution of processing plans on board remote sensors. These plans

  9. Resume of the status and benefits of the two-segment approach and its applicability to the jet transport fleet

    NASA Technical Reports Server (NTRS)

    Denery, D. G.; White, K. C.; Drinkwater, F. J., III

    1974-01-01

    NASA, in cooperation with the FAA, is evaluating the two-segment approach as a routine procedure for reducing aircraft noise. The program calls for separate flight evaluations using a 727 and a DC-8, and an extrapolation of these results to determine the adaptability of the technique to the rest of the fleet. The total program is reviewed. The profile and procedures developed and the noise reduction achievable are presented. The vortex characteristics behind an aircraft on a two-segment path is covered. Finally, cost estimates for retrofitting aircraft with two-segment avionics are presented.

  10. Fleet vehicles in the Unites States: composition, operating characteristics, and fueling practices

    SciTech Connect

    Miaou, S.P.; Hu, P.S.; Young, J.R.

    1992-05-01

    As fleets become a larger proportion of the new vehicle population on the road, they have more influence on the characteristics of the total US motor vehicle population. One of the characteristics which fleets are expected to have the most influence on is the overall vehicle fuel economy. In addition, because of the relatively large market share and the high turnover rate of fleet vehicles, fleets have been considered as a useful initial market for alternative fuel vehicles. In order to analyze fleet market potential and likely market penetration of alternative fuel vehicles and to infrastructure requirements for successful operations of these vehicles in the future, information on fleet sizes and composition, fleet vehicle operating characteristics (such as daily/annual miles of travel), fuel efficiency, and refueling practices, is essential. The purpose of this report is to gather and summarize information from the latest data sources available pertaining to fleet vehicles in the US This report presents fleet vehicle data on composition, operating characteristics, and fueling practices. The questions these data are intended to address include: (1) How are fleet vehicles operated? (2) Where are they located? and (3) What are their usual fueling practices? Since a limited number of alternative fuel fleet vehicles are already in use, data on these vehicles are also included in this report. 17 refs.

  11. Fleet vehicles in the Unites States: composition, operating characteristics, and fueling practices

    SciTech Connect

    Miaou, S.P.; Hu, P.S. ); Young, J.R. )

    1992-05-01

    As fleets become a larger proportion of the new vehicle population on the road, they have more influence on the characteristics of the total US motor vehicle population. One of the characteristics which fleets are expected to have the most influence on is the overall vehicle fuel economy. In addition, because of the relatively large market share and the high turnover rate of fleet vehicles, fleets have been considered as a useful initial market for alternative fuel vehicles. In order to analyze fleet market potential and likely market penetration of alternative fuel vehicles and to infrastructure requirements for successful operations of these vehicles in the future, information on fleet sizes and composition, fleet vehicle operating characteristics (such as daily/annual miles of travel), fuel efficiency, and refueling practices, is essential. The purpose of this report is to gather and summarize information from the latest data sources available pertaining to fleet vehicles in the US This report presents fleet vehicle data on composition, operating characteristics, and fueling practices. The questions these data are intended to address include: (1) How are fleet vehicles operated (2) Where are they located and (3) What are their usual fueling practices Since a limited number of alternative fuel fleet vehicles are already in use, data on these vehicles are also included in this report. 17 refs.

  12. Quality assessment of marine geoscience data collected with the U.S. academic oceanographic research fleet

    NASA Astrophysics Data System (ADS)

    Carbotte, S. M.; O'hara, S. H.; Ferrini, V.; Arko, R. A.; Morton, J. J.; Sweeney, A. D.; Clark, D.; Miller, S. P.; Stocks, K.; Chandler, C. L.; Maffei, A. R.; Smith, S. R.; Bourassa, M. A.

    2011-12-01

    Marine science data collected using the U.S. academic research fleet support a diverse array of investigations across the ocean sciences, targeting important questions ranging from the impacts of global change on ocean chemistry and ecosystems, to the structure and dynamics of ocean circulation, to the nature of volcanic and earthquake processes at the global plate boundaries. Each vessel within the academic fleet is equipped with a suite of sensors (geophysical, water column, and meteorological) available for continuous operation during each expedition, that provide characterization of basic environmental conditions from sea surface to subseafloor. Given the vast expanse of the oceans, many expeditions collect data in previously unexplored regions and these data are of high value for later re-use to build global syntheses, climatologies, and historical time series of ocean properties. Understanding the quality of these "underway" data streams is essential for any of these science applications. However, documentation of data quality is rare and historically, routine quality assessment (QA) of these data streams has been lacking. In most cases, QA has been the domain of the science party for each expedition but limited to the data types of interest for the scientific goals of the specific program, with the quality of other underway data types remaining unassessed. Under the Rolling Deck to Repository (R2R) program, QA of sensor data collected across the academic fleet will be routinely conducted as part of the R2R data pipeline that begins with the submission of cruise data distributions by ship operators. R2R will assemble datasets and documentation, and perform QA for submission to the NOAA National Data Centers (NDCs) for long-term archiving. The goals of the QA are two fold: 1. To provide feedback to shipboard operators to ensure that high quality data are consistently acquired, and 2. To inform future science users of the status of a field data set with

  13. Adaptive Wavelet Transforms

    SciTech Connect

    Szu, H.; Hsu, C.

    1996-12-31

    Human sensors systems (HSS) may be approximately described as an adaptive or self-learning version of the Wavelet Transforms (WT) that are capable to learn from several input-output associative pairs of suitable transform mother wavelets. Such an Adaptive WT (AWT) is a redundant combination of mother wavelets to either represent or classify inputs.

  14. CleanFleet. Final report: Volume 5, employee attitude assessment

    SciTech Connect

    1995-12-01

    The experiences of couriers, operations managers, vehicle handlers (refuelers), and mechanics who drove and/or worked with alternative fuel vehicles, and the attitudes and perceptions of people with these experiences, are examined. Five alternative fuels studied in the CleanFleet project are considers& compressed natural gas, propane gas, California Phase 2 reformulated gasoline, M-85, and electricity. The three major areas of interest include comparative analysis of issues such as health, safety and vehicle performance, business issues encompassing several facets of station operations, and personal commentary and opinions about the CleanFleet project and the alterative fuels. Results of the employee attitude assessment are presented as both statistical and qualitative analysis.

  15. Monitoring fleets of electric vehicles: optimizing operational use and maintenance

    NASA Astrophysics Data System (ADS)

    Lenain, P.; Kechmire, M.; Smaha, J. P.

    Electric vehicles can make a substantial contribution to an improved urban environment. Reduced atmospheric pollution and noise emissions make the increased use of electric vehicles highly desirable and their suitability for dedicated fleets of vehicles is well recognized. As a result, a suitable system of supervision and management is necessary for fleet operators, to allow them to see the key parameters for the optimum use of the electric vehicle at all times. A computer-based data acquisition and analysis system will allow access to critical control parameters and display the operation of chargers and batteries in real time. Battery condition and charging can be followed. Information is stored in a database and can be readily analyzed and retrieved to manage extensive charging installations. In this paper, the operation of a battery/charger management system is described. The effective use of the system in electric utility vans is demonstrated.

  16. Controlled Hydrogen Fleet and Infrastructure Demonstration and Validation Project

    SciTech Connect

    Stottler, Gary

    2012-02-08

    General Motors, LLC and energy partner Shell Hydrogen, LLC, deployed a system of hydrogen fuel cell electric vehicles integrated with a hydrogen fueling station infrastructure to operate under real world conditions as part of the U.S. Department of Energy's Controlled Hydrogen Fleet and Infrastructure Validation and Demonstration Project. This technical report documents the performance and describes the learnings from progressive generations of vehicle fuel cell system technology and multiple approaches to hydrogen generation and delivery for vehicle fueling.

  17. The ethanol heavy-duty truck fleet demonstration project

    SciTech Connect

    1997-06-01

    This project was designed to test and demonstrate the use of a high- percentage ethanol-blended fuel in a fleet of heavy-duty, over-the- road trucks, paying particular attention to emissions, performance, and repair and maintenance costs. This project also represents the first public demonstration of the use of ethanol fuels as a viable alternative to conventional diesel fuel in heavy-duty engines.

  18. Executive Order 13514: Federal Leadership in Environmental, Energy, and Economic Performance; Comprehensive Federal Fleet Management Handbook (Book)

    SciTech Connect

    Daley, R.; Ahdieh, N.; Bentley, J.

    2014-01-01

    A comprehensive Federal Fleet Management Handbook that builds upon the "Guidance for Federal Agencies on E.O. 13514 Section 12-Federal Fleet Management" and provides information to help fleet managers select optimal greenhouse gas and petroleum reduction strategies for each location, meeting or exceeding related fleet requirements, acquiring vehicles to support these strategies while minimizing fleet size and vehicle miles traveled, and refining strategies based on agency performance.

  19. Field Operations Program Neighborhood Electric Vehicles - Fleet Survey

    SciTech Connect

    Francfort, James Edward; Carroll, M.

    2001-07-01

    This report summarizes a study of 15 automotive fleets that operate neighborhood electric vehicles(NEVs) in the United States. The information was obtained to help Field Operations Program personnel understand how NEVs are being used, how many miles they are being driven, and if they are being used to replace other types of fleet vehicles or as additions to fleets. (The Field Operations Program is a U.S. Department of Energy Program within the DOE Office of Energy Efficiency and Renewable Energy, Transportation Technologies). The NEVs contribution to petroleum avoidance and cleaner air can be estimated based on the miles driven and by assuming gasoline use and air emissions values for the vehicles being replaced. Gasoline and emissions data for a Honda Civic are used as the Civic has the best fuel use for a gasoline-powered vehicle and very clean emissions. Based on these conservation assumptions, the 348 NEVs are being driven a total of about 1.2 million miles per year. This equates to an average of 3,409 miles per NEV annually or 9 miles per day. It is estimated that 29,195 gallons of petroleum use is avoided annually by the 348 NEVs. This equates to 87 gallons of petroleum use avoided per NEV, per year. Using the 348 NEVs avoids the generation of at least 775 pounds of smog- forming emissions annually.

  20. Field Operations Program - Neighborhood Electric Vehicle Fleet Use

    SciTech Connect

    Francfort, J. E.; Carroll, M. R.

    2001-07-02

    This report summarizes a study of 15 automotive fleets that operate neighborhood electric vehicles (NEVs) in the United States. The information was obtained to help Field Operations Program personnel understand how NEVs are being used, how many miles they are being driven, and if they are being used to replace other types of fleet vehicles or as additions to fleets. (The Field Operations Program is a U.S. Department of Energy Program within the DOE Office of Energy Efficiency and Renewable Energy, Transportation Technologies). The NEVs contribution to petroleum avoidance and cleaner air can be estimated based on the miles driven and by assuming gasoline use and air emissions values for the vehicles being replaced. Gasoline and emissions data for a Honda Civic are used as the Civic has the best fuel use for a gasoline-powered vehicle and very clean emissions. Based on these conservation assumptions, the 348 NEVs are being driven a total of about 1.2 million miles per year. This equates to an average of 3,409 miles per NEV annually or 9 miles per day. It is estimated that 29,195 gallons of petroleum use is avoided annually by the 348 NEVs. This equates to 87 gallons of petroleum use avoided per NEV, per year. Using the 348 NEVs avoids the generation of at least 775 pounds of smog-forming emissions annually.

  1. First interim report of the Federal Fleet Conversion Task Force

    SciTech Connect

    Not Available

    1993-08-01

    The Federal Fleet Conversion Task Force was created by Executive Order 12844, signed by President Clinton on April 21, 1993. In the Order, the President directed that purchases of alternative fueled vehicles by the Federal Government be substantially increased beyond the levels required by current law. The President charged the Task Force with developing recommendations for carrying out the Executive Order, with special emphasis on setting a course that will lead to the widespread use of alternative fueled vehicles by Federal, State, and local government fleets, by private fleets and, ultimately, by individuals. The chief recommendation of the Task Force is the establishment of a Presidential Clean Cities Initiative. To support creation of the Presidential Initiative, the Task Force identified 38 cities and regions, prioritized into three tiers, for concentrating the Initiative`s efforts in Fiscal Years 1994 through 1996. This concentration of effort is key to the effectiveness of the Initiative. The 38 cities and regions would receive priority funding for Federal vehicle purchases and for infrastructure development. In addition, the Task Force has made specific recommendations for overcoming numerous regulatory, economic, and technical barriers that have slowed the introduction of alternative fueled vehicles into general use.

  2. The Fleet Application for Scheduling and Tracking (FAST) Management Website

    NASA Technical Reports Server (NTRS)

    Marrero-Perez, Radames J.

    2014-01-01

    The FAST application was designed to replace the paper and pen method of checking out and checking in GSA Vehicles at KSC. By innovating from a paper and pen based checkout system to a fully digital one, not only the resources wasted by printing the checkout forms have been reduced, but it also reduces significantly the time that users and fleet managers need to interact with the system as well as improving the record accuracy for each vehicle. The vehicle information is pulled from a centralized database server in the SPSDL. In an attempt to add a new feature to the FAST application, the author of this report (alongside the FAST developers) has been designing and developing the FAST Management Website. The GSA fleet managers had to rely on the FAST developers in order to add new vehicles, edit vehicles and previous transactions, or for generating vehicles reports. By providing an easy-to-use FAST Management Website portal, the GSA fleet managers are now able to easily move vehicles, edit records, and print reports.

  3. Through-tunnel estimates of vehicle fleet emission factors

    NASA Astrophysics Data System (ADS)

    Brimblecombe, Peter; Townsend, Thomas; Lau, Chui Fong; Rakowska, Agata; Chan, Tat Leung; Močnik, Griša; Ning, Zhi

    2015-12-01

    On-road measurements of traffic-related gas and particle pollutant concentrations in three tunnels in Hong Kong and high resolution pollutant concentration profiles obtained while driving through the tunnels were used to derive the individual pollutant gradients using parametric and non-parametric (Sen-Thiel) slopes and compared with the commonly used entrance-exit two points calculation. The fuel based emission factors of measured pollutants for individual tunnels at different times of day were derived from gradients using a new method based on fuel carbon balance principle. Combined with the tunnel traffic volume and composition, the average tunnel emission factors were analyzed by linear regression to derive the diesel fleet emission factors. Average nitrogen oxides (NOx) and black carbon (BC) emission factor for diesel fleets are 29.3 ± 11.0 gNO2 kg-1 and 1.28 ± 0.76 g kg-1 of fuel, respectively. The results from the study were compared with the emission data from vehicle chasing approaches and the literature, showing reasonable agreement. Practical limitations and future direction for improvement of our method were also discussed. The method presented in this study provides a convenient drive-through approach for fast determination of tunnel and individual vehicle fleet emission factors. It can be used as an effective and fast approach to validate the emission inventory and to evaluate the effectiveness of policy intervention on the traffic emissions.

  4. Documentation for propane fleet conversion cost-effectiveness model

    NASA Astrophysics Data System (ADS)

    Taylor, D.; Euritt, M.; Mahmassani, H.

    1992-10-01

    Increased emphasis on energy efficiency and air quality has resulted in a number of state and federal initiatives examining the use of alternative fuels for motor vehicles. Texas instituted an alternative fuels program for public fleet operations beginning in the 1991-92 fiscal year. Life-cycle cost/benefit models for evaluating the economic implications of the action have been developed at the University of Texas at Austin Center for Transportation Research for both compressed natural gas (CNG) and propane. The report documents the various input data, calculations, and assumptions of the Propane Net Present Value (NPV) model. A similar report (number 983-1) documents the same for the CNG model. Input data with constant values across different fleets and locations are discussed first and include basic parameters for on-board storage capacity, vehicle conversion costs, equipment salvage values, etc. Variable input data, reflecting a given fleet size, composition, and location, include the number and types of vehicles, fuel consumption, etc. The next section presents the formulas for the internal model calculations. The final section discusses the basic assumptions underlying the model.

  5. Through-tunnel estimates of vehicle fleet emission factors

    NASA Astrophysics Data System (ADS)

    Brimblecombe, Peter; Townsend, Thomas; Lau, Chui Fong; Rakowska, Agata; Chan, Tat Leung; Močnik, Griša; Ning, Zhi

    2015-12-01

    On-road measurements of traffic-related gas and particle pollutant concentrations in three tunnels in Hong Kong and high resolution pollutant concentration profiles obtained while driving through the tunnels were used to derive the individual pollutant gradients using parametric and non-parametric (Sen-Thiel) slopes and compared with the commonly used entrance-exit two points calculation. The fuel based emission factors of measured pollutants for individual tunnels at different times of day were derived from gradients using a new method based on fuel carbon balance principle. Combined with the tunnel traffic volume and composition, the average tunnel emission factors were analyzed by linear regression to derive the diesel fleet emission factors. Average nitrogen oxides (NOx) and black carbon (BC) emission factor for diesel fleets are 29.3 ± 11.0 gNO2 kg-1 and 1.28 ± 0.76 g kg-1 of fuel, respectively. The results from the study were compared with the emission data from vehicle chasing approaches and the literature, showing reasonable agreement. Practical limitations and future direction for improvement of our method were also discussed. The method presented in this study provides a convenient drive-through approach for fast determination of tunnel and individual vehicle fleet emission factors. It can be used as an effective and fast approach to validate the emission inventory and to evaluate the effectiveness of policy intervention on the traffic emissions.

  6. SensorNet Node Suite

    2004-09-01

    The software in the SensorNet Node adopts and builds on IEEE 1451 interface principles to read data from and control sensors, stores the data in internal database structures, and transmits it in adapted Web Feature Services protocol packets to the SensorNet database. Failover software ensures that at least one available mode of communication remains alive.

  7. Level Sensor for Cryogenic Fluids

    NASA Technical Reports Server (NTRS)

    Simmons, N. E.; Schroff, R. A.

    1983-01-01

    Hot wire sensor combined with voltage-comparator circuit monitors liquid level in cryogenic-fluid storage tanks. Sensor circuit adaptable to different liquids and sensors. Constant-current source drives current through sensing probe and fixed resistor. Voltage comparator circuits interpret voltage drops to tell whether probe is immersed in liquid and is current in probe.

  8. NEEDS - Information Adaptive System

    NASA Technical Reports Server (NTRS)

    Kelly, W. L.; Benz, H. F.; Meredith, B. D.

    1980-01-01

    The Information Adaptive System (IAS) is an element of the NASA End-to-End Data System (NEEDS) Phase II and is focused toward onboard image processing. The IAS is a data preprocessing system which is closely coupled to the sensor system. Some of the functions planned for the IAS include sensor response nonuniformity correction, geometric correction, data set selection, data formatting, packetization, and adaptive system control. The inclusion of these sensor data preprocessing functions onboard the spacecraft will significantly improve the extraction of information from the sensor data in a timely and cost effective manner, and provide the opportunity to design sensor systems which can be reconfigured in near real-time for optimum performance. The purpose of this paper is to present the preliminary design of the IAS and the plans for its development.

  9. Real-time turbulence profiling with a pair of laser guide star Shack-Hartmann wavefront sensors for wide-field adaptive optics systems on large to extremely large telescopes.

    PubMed

    Gilles, L; Ellerbroek, B L

    2010-11-01

    Real-time turbulence profiling is necessary to tune tomographic wavefront reconstruction algorithms for wide-field adaptive optics (AO) systems on large to extremely large telescopes, and to perform a variety of image post-processing tasks involving point-spread function reconstruction. This paper describes a computationally efficient and accurate numerical technique inspired by the slope detection and ranging (SLODAR) method to perform this task in real time from properly selected Shack-Hartmann wavefront sensor measurements accumulated over a few hundred frames from a pair of laser guide stars, thus eliminating the need for an additional instrument. The algorithm is introduced, followed by a theoretical influence function analysis illustrating its impulse response to high-resolution turbulence profiles. Finally, its performance is assessed in the context of the Thirty Meter Telescope multi-conjugate adaptive optics system via end-to-end wave optics Monte Carlo simulations. PMID:21045893

  10. Development and Flight Testing of an Adaptive Vehicle Health-Monitoring Architecture

    NASA Technical Reports Server (NTRS)

    Woodard, Stanley E.; Coffey, Neil C.; Gonzalez, Guillermo A.; Taylor, B. Douglas; Brett, Rube R.; Woodman, Keith L.; Weathered, Brenton W.; Rollins, Courtney H.

    2002-01-01

    On going development and testing of an adaptable vehicle health-monitoring architecture is presented. The architecture is being developed for a fleet of vehicles. It has three operational levels: one or more remote data acquisition units located throughout the vehicle; a command and control unit located within the vehicle, and, a terminal collection unit to collect analysis results from all vehicles. Each level is capable of performing autonomous analysis with a trained expert system. The expert system is parameterized, which makes it adaptable to be trained to both a user's subject reasoning and existing quantitative analytic tools. Communication between all levels is done with wireless radio frequency interfaces. The remote data acquisition unit has an eight channel programmable digital interface that allows the user discretion for choosing type of sensors; number of sensors, sensor sampling rate and sampling duration for each sensor. The architecture provides framework for a tributary analysis. All measurements at the lowest operational level are reduced to provide analysis results necessary to gauge changes from established baselines. These are then collected at the next level to identify any global trends or common features from the prior level. This process is repeated until the results are reduced at the highest operational level. In the framework, only analysis results are forwarded to the next level to reduce telemetry congestion. The system's remote data acquisition hardware and non-analysis software have been flight tested on the NASA Langley B757's main landing gear. The flight tests were performed to validate the following: the wireless radio frequency communication capabilities of the system, the hardware design, command and control; software operation and, data acquisition, storage and retrieval.

  11. Initial development of a practical safety audit tool to assess fleet safety management practices.

    PubMed

    Mitchell, Rebecca; Friswell, Rena; Mooren, Lori

    2012-07-01

    Work-related vehicle crashes are a common cause of occupational injury. Yet, there are few studies that investigate management practices used for light vehicle fleets (i.e. vehicles less than 4.5 tonnes). One of the impediments to obtaining and sharing information on effective fleet safety management is the lack of an evidence-based, standardised measurement tool. This article describes the initial development of an audit tool to assess fleet safety management practices in light vehicle fleets. The audit tool was developed by triangulating information from a review of the literature on fleet safety management practices and from semi-structured interviews with 15 fleet managers and 21 fleet drivers. A preliminary useability assessment was conducted with 5 organisations. The audit tool assesses the management of fleet safety against five core categories: (1) management, systems and processes; (2) monitoring and assessment; (3) employee recruitment, training and education; (4) vehicle technology, selection and maintenance; and (5) vehicle journeys. Each of these core categories has between 1 and 3 sub-categories. Organisations are rated at one of 4 levels on each sub-category. The fleet safety management audit tool is designed to identify the extent to which fleet safety is managed in an organisation against best practice. It is intended that the audit tool be used to conduct audits within an organisation to provide an indicator of progress in managing fleet safety and to consistently benchmark performance against other organisations. Application of the tool by fleet safety researchers is now needed to inform its further development and refinement and to permit psychometric evaluation. PMID:22342958

  12. Influenza sensor

    DOEpatents

    Swanson, Basil I.; Song, Xuedong; Unkefer, Clifford; Silks, III, Louis A.; Schmidt, Jurgen G.

    2003-09-30

    A sensor for the detection of tetrameric multivalent neuraminidase within a sample is disclosed, where a positive detection indicates the presence of a target virus within the sample. Also disclosed is a trifunctional composition of matter including a trifunctional linker moiety with groups bonded thereto including (a) an alkyl chain adapted for attachment to a substrate, (b) a fluorescent moiety capable of generating a fluorescent signal, and (c) a recognition moiety having a spacer group of a defined length thereon, the recognition moiety capable of binding with tetrameric multivalent neuraminidase.

  13. Influenza Sensor

    DOEpatents

    Swanson, Basil I.; Song, Xuedong; Unkefer, Clifford; Silks, III, Louis A.; Schmidt, Jurgen G.

    2006-03-28

    A sensor for the detection of tetrameric multivalent neuraminidase within a sample is disclosed, where a positive detection indicates the presence of a target virus within the sample. Also disclosed is a trifunctional composition of matter including a trifunctional linker moiety with groups bonded thereto including (a) an alkyl chain adapted for attachment to a substrate, (b) a fluorescent moiety capable of generating a fluorescent signal, and (c) a recognition moiety having a spacer group of a defined length thereon, the recognition moiety capable of binding with tetrameric multivalent neuraminidase.

  14. Influenza Sensor

    DOEpatents

    Swanson, Basil I.; Song, Xuedong; Unkefer, Clifford; Silks, III, Louis A.; Schmidt, Jurgen G.

    2005-05-17

    A sensor for the detection of tetrameric multivalent neuraminidase within a sample is disclosed, where a positive detection indicates the presence of a target virus within the sample. Also disclosed is a trifunctional composition of matter including a trifunctional linker moiety with groups bonded thereto including (a) an alkyl chain adapted for attachment to a substrate, (b) a fluorescent moiety capable of generating a fluorescent signal, and (c) a recognition moiety having a spacer group of a defined length thereon, the recognition moiety capable of binding with tetrameric multivalent neuraminidase.

  15. Hydrogen sensor

    DOEpatents

    Duan, Yixiang; Jia, Quanxi; Cao, Wenqing

    2010-11-23

    A hydrogen sensor for detecting/quantitating hydrogen and hydrogen isotopes includes a sampling line and a microplasma generator that excites hydrogen from a gas sample and produces light emission from excited hydrogen. A power supply provides power to the microplasma generator, and a spectrometer generates an emission spectrum from the light emission. A programmable computer is adapted for determining whether or not the gas sample includes hydrogen, and for quantitating the amount of hydrogen and/or hydrogen isotopes are present in the gas sample.

  16. Fleet Compliance Results for MY 2010/FY 2011, EPAct Alternative Fuel Transportation Program: State and Alternative Fuel Provider Fleet Compliance Annual Report (Brochure)

    SciTech Connect

    Not Available

    2012-03-01

    This annual report summarizes the compliance results of state and alternative fuel provider fleets covered by the Energy Policy Act of 1992 (EPAct) for model year 2010/fiscal year 2011. The U.S. Department of Energy (DOE) regulates covered state and alternative fuel provider (SFP) fleets under the Energy Policy Act of 1992 (EPAct), as amended. For model year (MY) 2010, the compliance rate for the 2911 covered SFP fleets was 100%. Fleets used either Standard Compliance or Alternative Compliance. The 279 fleets that used Standard Compliance exceeded their aggregate MY 2010 acquisition requirements by 61%. The 12 covered fleets that complied using Alternative Compliance exceeded their aggregate MY 2010 petroleum-use-reduction requirements by 89%. Overall, DOE saw modest decreases from MY 2009 in biodiesel fuel use credits earned and in the number of light-duty vehicles (LDVs) acquired. Compared to years before MY 2009, these rates were far lower. Because covered fleets acquired fewer new vehicles overall in MY 2010, the requirement for alternative fuel vehicles (AFVs), which is proportional to new acquisitions, also dropped.

  17. Autonomous sensor manager agents (ASMA)

    NASA Astrophysics Data System (ADS)

    Osadciw, Lisa A.

    2004-04-01

    Autonomous sensor manager agents are presented as an algorithm to perform sensor management within a multisensor fusion network. The design of the hybrid ant system/particle swarm agents is described in detail with some insight into their performance. Although the algorithm is designed for the general sensor management problem, a simulation example involving 2 radar systems is presented. Algorithmic parameters are determined by the size of the region covered by the sensor network, the number of sensors, and the number of parameters to be selected. With straight forward modifications, this algorithm can be adapted for most sensor management problems.

  18. Aging Aircraft Transparencies: AN Italian Air Force Fleet Case History

    NASA Astrophysics Data System (ADS)

    Caucci, D.; Aiello, L.; Bagnoli, F.; Bernabei, M.

    2008-08-01

    Aircraft acrylic transparencies are structural components that must withstand flight and ground loads. Crazing occurrence, known as Environmental Stress Cracking (ESC), causes their substitution during aircraft maintenance operations. This form of aging is mainly a physical phenomenon due to the interaction of transparencies base material with an active liquid and leads craze formation at lower stress that would be required in air. In this paper, an extensive phenomenon of network ESC occurred on transparencies of many aircrafts operating in the same fleet was investigated. Cover application while parking was found to be the critical aspect in crazing appearance, thus acting as physical shield for condensed water and heat transferring.

  19. Automated Image Intelligence Adaptive Sensor Management System for High Altitude Long Endurance UAVs in a Dynamic and Anti-Access Area Denial Environment

    NASA Astrophysics Data System (ADS)

    Kim, Gi Young

    The problem we investigate deals with an Image Intelligence (IMINT) sensor allocation schedule for High Altitude Long Endurance UAVs in a dynamic and Anti-Access Area Denial (A2AD) environment. The objective is to maximize the Situational Awareness (SA) of decision makers. The value of SA can be improved in two different ways. First, if a sensor allocated to an Areas of Interest (AOI) detects target activity, then the SA value will be increased. Second, the SA value increases if an AOI is monitored for a certain period of time, regardless of target detections. These values are functions of the sensor allocation time, sensor type and mode. Relatively few studies in the archival literature have been devoted to an analytic, detailed explanation of the target detection process, and AOI monitoring value dynamics. These two values are the fundamental criteria used to choose the most judicious sensor allocation schedule. This research presents mathematical expressions for target detection processes, and shows the monitoring value dynamics. Furthermore, the dynamics of target detection is the result of combined processes between belligerent behavior (target activity) and friendly behavior (sensor allocation). We investigate these combined processes and derive mathematical expressions for simplified cases. These closed form mathematical models can be used for Measures of Effectiveness (MOEs), i.e., target activity detection to evaluate sensor allocation schedules. We also verify these models with discrete event simulations which can also be used to describe more complex systems. We introduce several methodologies to achieve a judicious sensor allocation schedule focusing on the AOI monitoring value. The first methodology is a discrete time integer programming model which provides an optimal solution but is impractical for real world scenarios due to its computation time. Thus, it is necessary to trade off the quality of solution with computation time. The Myopic Greedy

  20. Magnetic current sensor

    NASA Technical Reports Server (NTRS)

    Black, Jr., William C. (Inventor); Hermann, Theodore M. (Inventor)

    1998-01-01

    A current determiner having an output at which representations of input currents are provided having an input conductor for the input current and a current sensor supported on a substrate electrically isolated from one another but with the sensor positioned in the magnetic fields arising about the input conductor due to any input currents. The sensor extends along the substrate in a direction primarily perpendicular to the extent of the input conductor and is formed of at least a pair of thin-film ferromagnetic layers separated by a non-magnetic conductive layer. The sensor can be electrically connected to a electronic circuitry formed in the substrate including a nonlinearity adaptation circuit to provide representations of the input currents of increased accuracy despite nonlinearities in the current sensor, and can include further current sensors in bridge circuits.

  1. Compliant tactile sensor for generating a signal related to an applied force

    NASA Technical Reports Server (NTRS)

    Torres-Jara, Eduardo (Inventor)

    2012-01-01

    Tactile sensor. The sensor includes a compliant convex surface disposed above a sensor array, the sensor array adapted to respond to deformation of the convex surface to generate a signal related to an applied force vector.

  2. Nuclear power fleets and uranium resources recovered from phosphates

    SciTech Connect

    Gabriel, S.; Baschwitz, A.; Mathonniere, G.

    2013-07-01

    Current light water reactors (LWR) burn fissile uranium, whereas some future reactors, as Sodium fast reactors (SFR) will be capable of recycling their own plutonium and already-extracted depleted uranium. This makes them a feasible solution for the sustainable development of nuclear energy. Nonetheless, a sufficient quantity of plutonium is needed to start up an SFR, with the plutonium already being produced in light water reactors. The availability of natural uranium therefore has a direct impact on the capacity of the reactors (both LWR and SFR) that we can build. It is therefore important to have an accurate estimate of the available uranium resources in order to plan for the world's future nuclear reactor fleet. This paper discusses the correspondence between the resources (uranium and plutonium) and the nuclear power demand. Sodium fast reactors will be built in line with the availability of plutonium, including fast breeders when necessary. Different assumptions on the global uranium resources are taken into consideration. The largely quoted estimate of 22 Mt of uranium recovered for phosphate rocks can be seriously downscaled. Based on our current knowledge of phosphate resources, 4 Mt of recoverable uranium already seems to be an upper bound value. The impact of the downscaled estimate on the deployment of a nuclear fleet is assessed accordingly. (authors)

  3. Three Component Velocity and Acceleration Measurement Using FLEET

    NASA Technical Reports Server (NTRS)

    Danehy, Paul M.; Bathel, Brett F.; Calvert, Nathan; Dogariu, Arthur; Miles, Richard P.

    2014-01-01

    The femtosecond laser electronic excitation and tagging (FLEET) method has been used to measure three components of velocity and acceleration for the first time. A jet of pure N2 issuing into atmospheric pressure air was probed by the FLEET system. The femtosecond laser was focused down to a point to create a small measurement volume in the flow. The long-lived lifetime of this fluorescence was used to measure the location of the tagged particles at different times. Simultaneous images of the flow were taken from two orthogonal views using a mirror assembly and a single intensified CCD camera, allowing two components of velocity to be measured in each view. These different velocity components were combined to determine three orthogonal velocity components. The differences between subsequent velocity components could be used to measure the acceleration. Velocity accuracy and precision were roughly estimated to be +/-4 m/s and +/-10 m/s respectively. These errors were small compared to the approx. 100 m/s velocity of the subsonic jet studied.

  4. Integrated operations/payloads/fleet analysis (executive summary)

    NASA Technical Reports Server (NTRS)

    1972-01-01

    The Integrated Operations/Payloads/Fleet Analysis predicts total national space program costs and launch vehicle traffic assuming either an expendable, a partially reusable or a fully reusable launch vehicle fleet. The payload system costs are estimated and reported for each payload program at the subsystem level, payload program level, user level and national level, providing complete system cost traceability. The analysis determines the primary changes to be expected for space payload programs and space operations in the space shuttle era. When the space shuttle becomes fully operational, not only will launch costs be reduced but refurbished satellite units will be flown instead of new units and maintenance will be performed on failing satellites. It is possible to implement the concepts of satellite refurbishment and maintenance because of the space shuttle's capability to retrieve and return payloads to the earth's surface. The two-way satellite transportation capability is extended to high energy orbits by use of the space shuttle/space tug combination.

  5. Protein S-sulfenylation is a fleeting molecular switch that regulates non-enzymatic oxidative folding

    PubMed Central

    Beedle, Amy E. M.; Lynham, Steven; Garcia-Manyes, Sergi

    2016-01-01

    The post-translational modification S-sulfenylation functions as a key sensor of oxidative stress. Yet the dynamics of sulfenic acid in proteins remains largely elusive due to its fleeting nature. Here we use single-molecule force-clamp spectroscopy and mass spectrometry to directly capture the reactivity of an individual sulfenic acid embedded within the core of a single Ig domain of the titin protein. Our results demonstrate that sulfenic acid is a crucial short-lived intermediate that dictates the protein's fate in a conformation-dependent manner. When exposed to the solution, sulfenic acid rapidly undergoes further chemical modification, leading to irreversible protein misfolding; when cryptic in the protein's microenvironment, it readily condenses with a neighbouring thiol to create a protective disulfide bond, which assists the functional folding of the protein. This mechanism for non-enzymatic oxidative folding provides a plausible explanation for redox-modulated stiffness of proteins that are physiologically exposed to mechanical forces, such as cardiac titin. PMID:27546612

  6. EPAct Alternative Fuel Transportation Program: State and Alternative Fuel Provider Fleet Compliance Annual Report; Fleet Compliance Results for MY 2013/FY 2014

    SciTech Connect

    2015-09-01

    Compliance rates for covered state government and alternative fuel provider fleets under the Alternative Fuel Transportation Program (pursuant to the Energy Policy Act or EPAct) are reported for MY 2013/FY 2014 in this publication.

  7. 33 CFR 165.1121 - Security Zone: Fleet Supply Center Industrial Pier, San Diego, CA.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Center Industrial Pier, San Diego, CA. 165.1121 Section 165.1121 Navigation and Navigable Waters COAST... Guard District § 165.1121 Security Zone: Fleet Supply Center Industrial Pier, San Diego, CA. (a... feet from the north, west, and south sides of the Fleet Industrial Supply Center enclosed by...

  8. 77 FR 18718 - Petroleum Reduction and Alternative Fuel Consumption Requirements for Federal Fleets

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-28

    ... petroleum consumption and increase in alternative fuel consumption for Federal fleets (77 FR 14,482 (Mar. 12...; ] DEPARTMENT OF ENERGY 10 CFR Part 438 RIN 1904-AB98 Petroleum Reduction and Alternative Fuel Consumption... increase in alternative fuel consumption for Federal fleets. With this Request for Information (RFI),...

  9. Clean Cities Plug-In Electric Vehicle Handbook for Fleet Managers

    SciTech Connect

    2012-04-01

    Plug-in electric vehicles (PEVs) are entering the automobile market and are viable alternatives to conventional vehicles. This guide for fleet managers describes the basics of PEV technology, PEV benefits for fleets, how to select the right PEV, charging a PEV, and PEV maintenance.

  10. 75 FR 8563 - Safety Zone; Fleet Week Maritime Festival, Pier 66, Elliott Bay, Seattle, WA

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-25

    ... public dockets in the January 17, 2008, issue of the Federal Register (73 FR 3316). Public Meeting We do... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; Fleet Week Maritime Festival, Pier 66... aerial spectator events associated with the annual Fleet Week Maritime Festival. Entry into,...

  11. 40 CFR 52.351 - United States Postal Service substitute Clean Fuel Fleet Program.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 3 2010-07-01 2010-07-01 false United States Postal Service substitute Clean Fuel Fleet Program. 52.351 Section 52.351 Protection of Environment ENVIRONMENTAL PROTECTION... § 52.351 United States Postal Service substitute Clean Fuel Fleet Program. Revisions to the...

  12. 78 FR 28625 - American Airlines, a Subsidiary of AMR Corporation, Tulsa International Airport, Fleet Services...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-05-15

    ... the Federal Register on March 26, 2013 (78 FR 18370). Pursuant to 29 CFR 90.18(c) reconsideration may... International Airport, Fleet Services Clerks, Tulsa, Oklahoma; Notice of Negative Determination Regarding... workers of American Airlines, a subsidiary of AMR Corporation, Tulsa International Airport, Fleet...

  13. 77 FR 5747 - Security Zones, Seattle's Seafair Fleet Week Moving Vessels, Puget Sound, WA

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-06

    ..., 2008, issue of the Federal Register (73 FR 3316). Public Meeting We do not now plan to hold a public... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA87 Security Zones, Seattle's Seafair Fleet Week Moving... not protected by the Naval Vessel Protection Zone in Seattle's Seafair Fleet Week, while those...

  14. 33 CFR 105.296 - Additional requirements-barge fleeting facilities.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... to handle those barges carrying, in bulk, cargoes regulated by 46 CFR chapter I, subchapters D or O... fleeting facilities. 105.296 Section 105.296 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF... Additional requirements-barge fleeting facilities. (a) At MARSEC Level 1, in addition to the requirements...

  15. 76 FR 3646 - Safety Requirements and Manning Exemption Eligibility on Distant Water Tuna Fleet Vessels

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-01-20

    ... notice regarding our public dockets in the January 17, 2008, issue of the Federal Register (73 FR 3316... SECURITY Coast Guard Safety Requirements and Manning Exemption Eligibility on Distant Water Tuna Fleet... availability of a draft policy regarding distant water tuna fleet vessels manning exemption eligibility...

  16. 76 FR 31351 - Safety Requirements and Manning Exemption Eligibility on Distant Water Tuna Fleet Vessels

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-31

    ...The Coast Guard announces the availability of Office of Vessel Activities Policy Letter 11-05 regarding Distant Water Tuna Fleet vessels manning exemption eligibility and safety requirements. This final policy clarifies the requirements to allow a distant water tuna fleet vessel to engage foreign citizens under a temporary manning...

  17. 41 CFR 102-34.330 - What is the Federal Fleet Report?

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 41 Public Contracts and Property Management 3 2012-01-01 2012-01-01 false What is the Federal Fleet Report? 102-34.330 Section 102-34.330 Public Contracts and Property Management Federal Property Management Regulations System (Continued) FEDERAL MANAGEMENT REGULATION PERSONAL PROPERTY 34-MOTOR VEHICLE MANAGEMENT Federal Fleet Report §...

  18. 40 CFR 88.304-94 - Clean-fuel Fleet Vehicle Credit Program.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... contained in 40 CFR part 88, subpart A. (b) Program administration. (1)(i) Each state in which there is all... 40 Protection of Environment 20 2011-07-01 2011-07-01 false Clean-fuel Fleet Vehicle Credit...) AIR PROGRAMS (CONTINUED) CLEAN-FUEL VEHICLES Clean-Fuel Fleet Program § 88.304-94 Clean-fuel...

  19. 47 CFR 80.55 - Application for a fleet station license.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 47 Telecommunication 5 2011-10-01 2011-10-01 false Application for a fleet station license. 80.55... SERVICES STATIONS IN THE MARITIME SERVICES Applications and Licenses § 80.55 Application for a fleet station license. (a) An applicant may apply for licenses for two or more radiotelephone stations...

  20. 47 CFR 80.55 - Application for a fleet station license.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 47 Telecommunication 5 2012-10-01 2012-10-01 false Application for a fleet station license. 80.55... station license. (a) An applicant may apply for licenses for two or more radiotelephone stations aboard different vessels on the same application. Under these circumstances a fleet station license may be...

  1. 47 CFR 80.55 - Application for a fleet station license.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 47 Telecommunication 5 2014-10-01 2014-10-01 false Application for a fleet station license. 80.55... station license. (a) An applicant may apply for licenses for two or more radiotelephone stations aboard different vessels on the same application. Under these circumstances a fleet station license may be...

  2. 47 CFR 80.55 - Application for a fleet station license.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 47 Telecommunication 5 2013-10-01 2013-10-01 false Application for a fleet station license. 80.55... station license. (a) An applicant may apply for licenses for two or more radiotelephone stations aboard different vessels on the same application. Under these circumstances a fleet station license may be...

  3. Modelling the Spatial Behaviour of a Tropical Tuna Purse Seine Fleet

    PubMed Central

    Davies, Tim K.; Mees, Chris C.; Milner-Gulland, E. J.

    2014-01-01

    Industrial tuna fisheries operate in the Indian, Atlantic and Pacific Oceans, but concerns over sustainability and environmental impacts of these fisheries have resulted in increased scrutiny of how they are managed. An important but often overlooked factor in the success or failure of tuna fisheries management is the behaviour of fishers and fishing fleets. Uncertainty in how a fishing fleet will respond to management or other influences can be reduced by anticipating fleet behaviour, although to date there has been little research directed at understanding and anticipating the human dimension of tuna fisheries. The aim of this study was to address gaps in knowledge of the behaviour of tuna fleets, using the Indian Ocean tropical tuna purse seine fishery as a case study. We use statistical modelling to examine the factors that influence the spatial behaviour of the purse seine fleet at broad spatiotemporal scales. This analysis reveals very high consistency between years in the use of seasonal fishing grounds by the fleet, as well as a forcing influence of biophysical ocean conditions on the distribution of fishing effort. These findings suggest strong inertia in the spatial behaviour of the fleet, which has important implications for predicting the response of the fleet to natural events or management measures (e.g., spatial closures). PMID:25462165

  4. 41 CFR 101-39.105-1 - Transfers from discontinued or curtailed fleet management systems.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... discontinued or curtailed fleet management systems. 101-39.105-1 Section 101-39.105-1 Public Contracts and Property Management Federal Property Management Regulations System FEDERAL PROPERTY MANAGEMENT REGULATIONS AVIATION, TRANSPORTATION, AND MOTOR VEHICLES 39-INTERAGENCY FLEET MANAGEMENT SYSTEMS...

  5. 41 CFR 101-39.104 - Notice of establishment of a fleet management system.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... of a fleet management system. 101-39.104 Section 101-39.104 Public Contracts and Property Management Federal Property Management Regulations System FEDERAL PROPERTY MANAGEMENT REGULATIONS AVIATION, TRANSPORTATION, AND MOTOR VEHICLES 39-INTERAGENCY FLEET MANAGEMENT SYSTEMS 39.1-Establishment, Modification,...

  6. 48 CFR 52.251-2 - Interagency Fleet Management System Vehicles and Related Services.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... Management System Vehicles and Related Services. 52.251-2 Section 52.251-2 Federal Acquisition Regulations... CLAUSES Text of Provisions and Clauses 52.251-2 Interagency Fleet Management System Vehicles and Related... to obtain interagency fleet management system vehicles and related services for use in...

  7. 41 CFR 101-39.104 - Notice of establishment of a fleet management system.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... of a fleet management system. 101-39.104 Section 101-39.104 Public Contracts and Property Management Federal Property Management Regulations System FEDERAL PROPERTY MANAGEMENT REGULATIONS AVIATION, TRANSPORTATION, AND MOTOR VEHICLES 39-INTERAGENCY FLEET MANAGEMENT SYSTEMS 39.1-Establishment, Modification,...

  8. 48 CFR 52.251-2 - Interagency Fleet Management System Vehicles and Related Services.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... Management System Vehicles and Related Services. 52.251-2 Section 52.251-2 Federal Acquisition Regulations... CLAUSES Text of Provisions and Clauses 52.251-2 Interagency Fleet Management System Vehicles and Related... to obtain interagency fleet management system vehicles and related services for use in...

  9. 48 CFR 52.251-2 - Interagency Fleet Management System Vehicles and Related Services.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... Management System Vehicles and Related Services. 52.251-2 Section 52.251-2 Federal Acquisition Regulations... CLAUSES Text of Provisions and Clauses 52.251-2 Interagency Fleet Management System Vehicles and Related... to obtain interagency fleet management system vehicles and related services for use in...

  10. 48 CFR 52.251-2 - Interagency Fleet Management System Vehicles and Related Services.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... Management System Vehicles and Related Services. 52.251-2 Section 52.251-2 Federal Acquisition Regulations... CLAUSES Text of Provisions and Clauses 52.251-2 Interagency Fleet Management System Vehicles and Related... to obtain interagency fleet management system vehicles and related services for use in...

  11. Providing Networking to the DEOS Fleet of Moored Ocean Observatories: High-Seas ROADNet.

    NASA Astrophysics Data System (ADS)

    Orcutt, J.; Berger, J.; Vernon, F.; Hansen, T.

    2003-12-01

    Recent advances in the technologies associated with computation, data telemetry and multidisciplinary sensors, have motivated the scientific community to develop a plan for long-term `ocean observatories' where sensors are deployed at the air-sea interface, within the water column, and on and beneath the seafloor. The establishment of a fleet of moored ocean buoy observatories will be an important element of the DEOS initiative, conceived as part of NSF's larger, more inclusive Ocean Observatories Initiative (OOI). These buoys will provide the infrastructure to connect the Internet to a network of ocean-bottom and ocean-column instruments. The most important requirements driving moored observatory design are the amount of power delivered to the seafloor and moored instruments and the telemetry rate that the buoy system must support between the instruments and the shore. Two designs have been developed, a wave-following discus and a spar buoy capable of delivering 500 W to the seafloor and telemetering at least 500 Mbytes of data per day to shore. The only cost-effective alternative for continuous moderate-bandwidth communication (>64 kbps) currently available is a C-Band or Ku-Band satellite system. A prototype C-Band system has been installed on the R/V Roger Revelle, the R/V Melville, and the R/V Thomas Thompson with a teleport hub at the San Diego supercomputer Center. This system provides full-period shipboard Internet connection as the ships operated over wide areas of the Pacific Ocean. The system has proved very effective in providing data, video, and voice communications for the ships' scientists and crew. The data connections to/from the ships are managed by the ROADNet (Real-time Observatories, Applications, and Data management Network) virtual object ring buffer (VORB) technology discussed in other papers in this session.

  12. 33 CFR 165.804 - Snake Island, Texas City, Texas; mooring and fleeting of vessels-safety zone.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...; mooring and fleeting of vessels-safety zone. 165.804 Section 165.804 Navigation and Navigable Waters COAST... Guard District § 165.804 Snake Island, Texas City, Texas; mooring and fleeting of vessels—safety zone... in case of an emergency. (c) Barges are prohibited from fleeting or grounding in the zone. (d) In...

  13. 75 FR 34927 - Safety Zone; Parade of Ships, Seattle SeaFair Fleet Week, Pier 66, Elliott Bay, WA

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-21

    ... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; Parade of Ships, Seattle SeaFair Fleet Week... with the Parade of Ships for the annual Seattle SeaFair Fleet Week. This action is intended to restrict... action is necessary to ensure the safety of spectators and participants attending Fleet Week...

  14. 49 CFR 37.185 - Fleet accessibility requirement for OTRB fixed-route systems of large operators.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 1 2010-10-01 2010-10-01 false Fleet accessibility requirement for OTRB fixed....185 Fleet accessibility requirement for OTRB fixed-route systems of large operators. Each large... percent of the buses in its fleet with which it provides fixed-route service are readily accessible to...

  15. 40 CFR 86.094-22 - Approval of application for certification; test fleet selections; determinations of parameters...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... certification; test fleet selections; determinations of parameters subject to adjustment for certification and...; test fleet selections; determinations of parameters subject to adjustment for certification and... may approve the application and select a test fleet in accordance with § 86.094-24. (b) Disapproval...

  16. 48 CFR 252.251-7001 - Use of Interagency Fleet Management System (IFMS) vehicles and related services.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 3 2010-10-01 2010-10-01 false Use of Interagency Fleet... Fleet Management System (IFMS) vehicles and related services. As prescribed in 251.205, use the following clause: Use of Interagency Fleet Management System (IFMS) Vehicles and Related Services (DEC...

  17. 77 FR 59749 - Special Local Regulations for Marine Events; San Francisco Bay Navy Fleet Week Parade of Ships...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-01

    ... Fleet Week Parade of Ships and Blue Angels Demonstration, San Francisco Bay, CA AGENCY: Coast Guard, DHS... sponsored Fleet Week Parade of Navy Ships, Blue Angels Flight Demonstrations, Ship Tours, and America's Cup... special local regulation for the annual San Francisco Bay Navy Fleet Week Parade of Ships and Blue...

  18. CleanFleet. Final report: Volume 7, vehicle emissions

    SciTech Connect

    1995-12-01

    Measurements of exhaust and evaporative emissions from Clean Fleet vans running on M-85, compressed natural gas (CNG), California Phase 2 reformulated gasoline (RFG), propane gas, and a control gasoline (RF-A) are presented. Three vans from each combination of vehicle manufacturer and fuel were tested at the California Air Resources Board (ARB) as they accumulated mileage in the demonstration. Data are presented on regulated emissions, ozone precursors, air toxics, and greenhouse gases. The emissions tests provide information on in-use emissions. That is, the vans were taken directly from daily commercial service and tested at the ARB. The differences in alternative fuel technology provide the basis for a range of technology options. The emissions data reflect these differences, with classes of vehicle/fuels producing either more or less emissions for various compounds relative to the control gasoline.

  19. Ideas for a three-aircraft planetary observing fleet

    NASA Astrophysics Data System (ADS)

    Carlson, David J.; Schumann, Ulrich

    2003-04-01

    A new generation of research aircraft, based on modern mid-sized business jets, will provide access to upper regions of the atmosphere and remote regions of the planet not reachable by the current research aircraft. Equipped with extensive research modifications, modern instruments, and advanced air-to-ground communication systems, these new aircraft will allow investigators to attack key questions in global atmospheric dynamics, global cycles of water and carbon, global energy budgets, and regional and global air quality and chemical transport. A three-aircraft fleet of these aircraft could provide unprecedented coordinated intercalibrated coverage of the planetary atmosphere and surfaces in a manner that greatly enhances the total ground, ocean, and satellite observing system.

  20. Integrated operations/payloads/fleet analysis. Volume 2: Payloads

    NASA Technical Reports Server (NTRS)

    1971-01-01

    The payloads for NASA and non-NASA missions of the integrated fleet are analyzed to generate payload data for the capture and cost analyses for the period 1979 to 1990. Most of the effort is on earth satellites, probes, and planetary missions because of the space shuttle's ability to retrieve payloads for repair, overhaul, and maintenance. Four types of payloads are considered: current expendable payload; current reusable payload; low cost expendable payload, (satellite to be used with expendable launch vehicles); and low cost reusable payload (satellite to be used with the space shuttle/space tug system). Payload weight analysis, structural sizing analysis, and the influence of mean mission duration on program cost are also discussed. The payload data were computerized, and printouts of the data for payloads for each program or mission are included.

  1. The spacecraft 'fleet' to comet Halley - An introduction

    NASA Technical Reports Server (NTRS)

    Tsurutani, B. T.

    1985-01-01

    Questions related to the formation and the characteristics of comets are discussed, and it is suggested that an evolutionary link exists between comets, prebiotic organic synthesis, and the origin of life as it is known. Fundamental questions about the solar wind interaction with comets, are considered, giving attention to the ionization mechanisms in the different cometary regions, the presence of field-aligned currents, and the cometary plasma tail. It is pointed out that some of the questions will soon be answered when the NASA-ESA International Cometary Explorer (ICE) goes through the tail of Giacobini-Zinner in September 1985, and when a five spacecraft 'fleet' arrives at comet Halley in March 1986.

  2. Expanding the Telepresence Paradigm to the UNOLS Fleet

    NASA Astrophysics Data System (ADS)

    Coleman, D.; Scowcroft, G.

    2014-12-01

    The Inner Space Center (ISC) at the University of Rhode Island Graduate School of Oceanography (URI-GSO) has been at the forefront of developing the tools, techniques, and protocols for telepresence-enabled ocean science exploration and education programs. Working primarily with the Ocean Exploration Trust's E/V Nautilus and the NOAA Ship Okeanos Explorer, the ISC facility and staff have supported dozens of research cruises with significant shore-based support, while delivering related educational programming across the globe. Through a partnership with the University National Oceanographic Laboratory System (UNOLS), the ISC is broadening its reach and capabilities to serve vessels in the U.S. academic research fleet, managed by UNOLS. The ISC has developed and used a portable shipboard "mobile telepresence unit" (MTU) on several UNOLS ships to support projects led by ocean scientists that employed the telepresence paradigm as part of their research and outreach programs. Utilizing the ISC facilities provides opportunities for effective, successful broader impact activities and shore-based remote science connectivity. With new UNOLS ships coming online, including the R/V Sikuliaq, the R/V Neil Armstrong, and the R/V Sally Ride, in addition to future Regional Class Research Vessels (RCRVs), telepresence capability has become a technical requirement for a variety of reasons. Older vessels are being retrofit with this forward-looking technology, and URI's research vessel, the R/V Endeavor, has been recently configured with technology to support telepresence operations. This presentation will provide an overview of the future of telepresence technology, its use in ocean science research and education, and advantages for using this capability to support broader impact activities. In addition, ISC successes, challenges, and lessons learned in employing telepresence technologies and methodologies onboard the academic research fleet will be discussed.

  3. Homogenization of Vehicle Fleet Frontal Crash Pulses from 2000–2010

    PubMed Central

    Locey, Caitlin M.; Garcia-Espana, J. Felipe; Toh, Akira; Belwadi, Aditya; Arbogast, Kristy B.; Maltese, Matthew R.

    2012-01-01

    Full-scale vehicle crash tests are performed globally to assess vehicle structure and restraint system performance. The crash pulse, captured by accelerometers mounted within the occupant compartment, measures the motion of the vehicle during the impact event. From an occupant’s perspective, the crash pulse is the inertial event to which the vehicle’s restraint systems must respond in order to mitigate the forces and accelerations that act on a passenger, and thus reduce injury risk. The objective of this study was to quantify the characteristics of crash pulses for different vehicle types in the contemporary North American fleet, and delineate current trends in crash pulse evolution. NHTSA and Transport Canada crash test databases were queried for full-frontal rigid barrier crash tests of passenger vehicles model year 2000–2010 with impact angle equaling zero degrees. Acceleration-time histories were analyzed for all accelerometers attached to the vehicle structure within the occupant compartment. Custom software calculated the following crash pulse characteristics (CPCs): peak deceleration, time of peak deceleration, onset rate, pulse duration, and change in velocity. Vehicle body types were classified by adapting the Highway Loss Data Institute (HLDI) methodology, and vehicles were assigned a generation start year in place of model year in order to more accurately represent structural change over time. 1094 vehicle crash tests with 2795 individual occupant compartment-mounted accelerometers were analyzed. We found greater peak decelerations and and shorter pulse durations across multiple vehicle types in newer model years as compared to older. For midsize passenger cars, large passenger cars, and large SUVs in 56 km/h rigid barrier tests, maximum deceleration increased by 0.40, 0.96, and 1.57 g/year respectively, and pulse duration decreased by 0.74, 1.87, and 2.51 ms/year. We also found that the crash pulse characteristics are becoming more homogeneous in

  4. An Optimization Method for Condition Based Maintenance of Aircraft Fleet Considering Prognostics Uncertainty

    PubMed Central

    Chen, Yiran; Sun, Bo; Li, Songjie

    2014-01-01

    An optimization method for condition based maintenance (CBM) of aircraft fleet considering prognostics uncertainty is proposed. The CBM and dispatch process of aircraft fleet is analyzed first, and the alternative strategy sets for single aircraft are given. Then, the optimization problem of fleet CBM with lower maintenance cost and dispatch risk is translated to the combinatorial optimization problem of single aircraft strategy. Remain useful life (RUL) distribution of the key line replaceable Module (LRM) has been transformed into the failure probability of the aircraft and the fleet health status matrix is established. And the calculation method of the costs and risks for mission based on health status matrix and maintenance matrix is given. Further, an optimization method for fleet dispatch and CBM under acceptable risk is proposed based on an improved genetic algorithm. Finally, a fleet of 10 aircrafts is studied to verify the proposed method. The results shows that it could realize optimization and control of the aircraft fleet oriented to mission success. PMID:24892046

  5. A sub-10 nA DC-balanced adaptive stimulator IC with multi-modal sensor for compact electro-acupuncture stimulation.

    PubMed

    Song, Kiseok; Lee, Hyungwoo; Hong, Sunjoo; Cho, Hyunwoo; Ha, Unsoo; Yoo, Hoi-Jun

    2012-12-01

    A compact electro-acupuncture (EA) system is proposed for a multi-modal feedback EA treatment. It is composed of a needle, a compact EA patch, and an interconnecting conductive thread. The 3 cm diameter compact EA patch is implemented with an adaptive stimulator IC and a small coin battery on the planar-fashionable circuit board (P-FCB) technology. The adaptive stimulator IC can form a closed current loop for even a single needle, and measure the electromyography (EMG) and the skin temperature to analyze the stimulation status as well as supply programmable stimulation current (40 μA-1 mA) with 5 different modes. The large time constant (LTC) sample and hold (S/H) current matching technique achieves the high-precision charge balancing ( <;10 nA) for the patient's safety. The measured data can be wirelessly transmitted to the external EA analyzer through the body channel communication (BCC) transceiver for the low power consumption. The external EA analyzer can show the patient's status, such as the muscle fatigue and the change of the skin temperature. Based on these analyses, the practitioner can adaptively change the stimulation parameters for the optimal treatment value. A 12.5 mm(2) 0.13 μm RF CMOS stimulator chip consumes 6.8 mW at 1.2 V supporting 32 different current levels. The proposed compact EA system is fully implemented and tested on the human body. PMID:23853254

  6. Adaptive MGS Phase Retrieval

    NASA Technical Reports Server (NTRS)

    Basinger, Scott A.; Bikkannavar, Siddarayappa; Cohen, David; Green, Joseph J.; Lou, John; Ohara, Catherine; Redding, David; Shi, Fang

    2008-01-01

    Adaptive MGS Phase Retrieval software uses the Modified Gerchberg-Saxton (MGS) algorithm, an image-based sensing method that can turn any focal plane science instrument into a wavefront sensor, avoiding the need to use external metrology equipment. Knowledge of the wavefront enables intelligent control of active optical systems.

  7. The Wave Glider°: A New Autonomous Surface Vehicle to Augment MBARI's Growing Fleet of Ocean Observing Systems

    NASA Astrophysics Data System (ADS)

    Tougher, B. B.

    2011-12-01

    Monterey Bay Aquarium Research Institute's (MBARI) evolving fleet of ocean observing systems has made it possible to collect information and data about a wide variety of ocean parameters, enabling researchers to better understand marine ecosystems. In collaboration with Liquid Robotics Inc, the designer of the Wave Glider autonomous surface vehicle (ASV), MBARI is adding a new capability to its suite of ocean observing tools. This new technology will augment MBARI research programs that use satellites, ships, moorings, drifters, autonomous underwater vehicles (AUVs) and remotely operated vehicles (ROVs) to improve data collection of temporally and spatially variable oceanographic features. The Wave Glider ASV derives its propulsion from wave energy, while sensors and communications are powered through the use of two solar panels and batteries, enabling it to remain at sea indefinitely. Wave Gliders are remotely controlled via real-time Iridium burst communications, which also permit real-time data telemetry. MBARI has developed Ocean Acidification (OA) moorings to continuously monitor the chemical and physical changes occurring in the ocean as a result of increased levels of atmospheric carbon dioxide (CO2). The moorings are spatially restricted by being anchored to the seafloor, so during the summer of 2011 the ocean acidification sensor suite designed for moorings was integrated into a Wave Glider ASV to increase both temporal and spatial ocean observation capabilities. The OA sensor package enables the measurement of parameters essential to better understanding the changing acidity of the ocean, specifically pCO2, pH, oxygen, salinity and temperature. The Wave Glider will also be equipped with a meteorological sensor suite that will measure air temperature, air pressure, and wind speed and direction. The OA sensor integration into a Wave Glider was part of MBARI's 2011 summer internship program. This project involved designing a new layout for the OA sensors

  8. Semiconductor sensors

    NASA Technical Reports Server (NTRS)

    Gatos, Harry C. (Inventor); Lagowski, Jacek (Inventor)

    1977-01-01

    A semiconductor sensor adapted to detect with a high degree of sensitivity small magnitudes of a mechanical force, presence of traces of a gas or light. The sensor includes a high energy gap (i.e., .about. 1.0 electron volts) semiconductor wafer. Mechanical force is measured by employing a non-centrosymmetric material for the semiconductor. Distortion of the semiconductor by the force creates a contact potential difference (cpd) at the semiconductor surface, and this cpd is determined to give a measure of the force. When such a semiconductor is subjected to illumination with an energy less than the energy gap of the semiconductors, such illumination also creates a cpd at the surface. Detection of this cpd is employed to sense the illumination itself or, in a variation of the system, to detect a gas. When either a gas or light is to be detected and a crystal of a non-centrosymmetric material is employed, the presence of gas or light, in appropriate circumstances, results in a strain within the crystal which distorts the same and the distortion provides a mechanism for qualitative and quantitative evaluation of the gas or the light, as the case may be.

  9. 41 CFR 102-34.290 - What forms do I use to report a crash involving a domestic fleet motor vehicle?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... report a crash involving a domestic fleet motor vehicle? 102-34.290 Section 102-34.290 Public Contracts... forms do I use to report a crash involving a domestic fleet motor vehicle? Use the following forms to report a domestic fleet crash. The forms should be carried in any domestic fleet motor vehicle....

  10. Mission Engineering of a Rapid Cycle Spacecraft Logistics Fleet

    NASA Technical Reports Server (NTRS)

    Holladay, Jon; McClendon, Randy (Technical Monitor)

    2002-01-01

    The requirement for logistics re-supply of the International Space Station has provided a unique opportunity for engineering the implementation of NASA's first dedicated pressurized logistics carrier fleet. The NASA fleet is comprised of three Multi-Purpose Logistics Modules (MPLM) provided to NASA by the Italian Space Agency in return for operations time aboard the International Space Station. Marshall Space Flight Center was responsible for oversight of the hardware development from preliminary design through acceptance of the third flight unit, and currently manages the flight hardware sustaining engineering and mission engineering activities. The actual MPLM Mission began prior to NASA acceptance of the first flight unit in 1999 and will continue until the de-commission of the International Space Station that is planned for 20xx. Mission engineering of the MPLM program requires a broad focus on three distinct yet inter-related operations processes: pre-flight, flight operations, and post-flight turn-around. Within each primary area exist several complex subsets of distinct and inter-related activities. Pre-flight processing includes the evaluation of carrier hardware readiness for space flight. This includes integration of payload into the carrier, integration of the carrier into the launch vehicle, and integration of the carrier onto the orbital platform. Flight operations include the actual carrier operations during flight and any required real-time ground support. Post-flight processing includes de-integration of the carrier hardware from the launch vehicle, de-integration of the payload, and preparation for returning the carrier to pre-flight staging. Typical space operations are engineered around the requirements and objectives of a dedicated mission on a dedicated operational platform (i.e. Launch or Orbiting Vehicle). The MPLM, however, has expanded this envelope by requiring operations with both vehicles during flight as well as pre-launch and post

  11. AVTA Federal Fleet PEV Readiness Data Logging and Characterization Study: Final Report

    SciTech Connect

    Schey, Stephen; Francfort, Jim

    2015-06-01

    Collect and evaluate data on federal fleet operations as part of the Advanced Vehicle Testing Activity’s Federal Fleet Vehicle Data Logging and Characterization Study. The Advanced Vehicle Testing Activity study seeks to collect and evaluate data to validate the utilization of advanced plug-in electric vehicle (PEV) transportation. This report summarizes the fleets studied to identify daily operational characteristics of select vehicles and report findings on vehicle and mission characterizations to support the successful introduction of PEVs into the agencies’ fleets. Individual observations of these selected vehicles provide the basis for recommendations related to electric vehicle adoption and whether a battery electric vehicle or plug-in hybrid electric vehicle (collectively referred to as PEVs) can fulfill the mission requirements.

  12. U.S. Naval Base, Pearl Harbor, Retail Warehouse, Fleet Landing Halawa, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    U.S. Naval Base, Pearl Harbor, Retail Warehouse, Fleet Landing Halawa, near Kamehameha Highway between Richardson Recreation Center & USS Arizona Memorial Visitor Center, Pearl City, Honolulu County, HI

  13. Monitoring measurement tools: new methods for driving continuous improvements in fleet measurement uncertainty

    NASA Astrophysics Data System (ADS)

    Solecky, Eric; Archie, Chas; Sendelbach, Matthew; Fiege, Ron; Zaitz, Mary; Shneyder, Dmitriy; Strocchia-rivera, Carlos; Munoz, Andres; Rangarajan, Srinivasan; Muth, William; Brendler, Andrew; Banke, Bill; Schulz, Bernd; Hartig, Carsten; Hoeft, Jon-Tobias; Vaid, Alok; Kelling, Mark; Bunday, Benjamin; Allgair, John

    2009-03-01

    Ever shrinking measurement uncertainty requirements are difficult to achieve for a typical metrology toolset, especially over the entire expected life of the fleet. Many times, acceptable performance can be demonstrated during brief evaluation periods on a tool or two in the fleet. Over time and across the rest of the fleet, the most demanding processes often have measurement uncertainty concerns that prevent optimal process control, thereby limiting premium part yield, especially on the most aggressive technology nodes. Current metrology statistical process control (SPC) monitoring techniques focus on maintaining the performance of the fleet where toolset control chart limits are derived from a stable time period. These tools are prevented from measuring product when a statistical deviation is detected. Lastly, these charts are primarily concerned with daily fluctuations and do not consider the overall measurement uncertainty. It is possible that the control charts implemented for a given toolset suggest a healthy fleet while many of these demanding processes continue to suffer measurement uncertainty issues. This is especially true when extendibility is expected in a given generation of toolset. With this said, there is a need to continually improve the measurement uncertainty of the fleet until it can no longer meet the needed requirements at which point new technology needs to be entertained. This paper explores new methods in analyzing existing SPC monitor data to assess the measurement performance of the fleet and look for opportunities to drive improvements. Long term monitor data from a fleet of overlay and scatterometry tools will be analyzed. The paper also discusses using other methods besides SPC monitors to ensure the fleet stays matched; a set of SPC monitors provides a good baseline of fleet stability but it cannot represent all measurement scenarios happening in product recipes. The analyses presented deal with measurement uncertainty on non

  14. The Department of Energy's Federal Methanol Fleet Project: A progress report

    SciTech Connect

    McGill, R.N.

    1987-11-12

    DOE's federal methanol fleet demonstration project is introducing methanol-fueled vehicles into government fleet operations with considerable success. The viability of methanol vehicles is being demonstrated, and vehicle technology is almost mature enough for production vehicles. Drivers seem to accept methanol vehicles as perfectly adequate compared to gasoline vehicles. Where the project goes from here with methanol vehicles is a function of need, economics and/or government initiative. These viewgraphs summarize the project results.

  15. Adaptive compensation of atmospheric turbulence utilizing an interferometric wave-front sensor and a high-resolution MEMS-based spatial light modulator

    SciTech Connect

    Baker, K; Stappaerts, E; Gavel, D; Tucker, J; Silva, D; Wilks, S; Olivier, S; Olsen, J

    2004-08-12

    Horizontal path correction of optical beam propagation presents a severe challenge to adaptive optics systems due to the short transverse coherence length and the high degree of scintillation incurred by propagation along these paths. The system presented operates with nearly monochromatic light. It does not require a global reconstruction of the phase, thereby eliminating issues with branch points and making its performance relatively unaffected by scintillation. The systems pixel count, 1024, and relatively high correction speed, in excess of 800 Hz, enable its use for correction of horizontal path beam propagation. We present results from laboratory and field tests of the system in which we have achieved Strehl ratios greater than 0.5.

  16. Multifunction sensor for target recognition

    NASA Astrophysics Data System (ADS)

    James, William M.; Lindberg, Perry C.

    1993-09-01

    The U.S. Army has a critical need for the capability provided by a multifunction sensor. This is (in effect) a smart sensor system that can adapt to environmental conditions and adjust its mode of operation to effectively counter any threat it meets. It will have an intelligent signal processor which has all of the system's sensor signals to choose from. The processor chooses the appropriate signal information to rapidly detect, acquire, track, and automatically identify all targets in the vicinity of the sensor under a wide variety of battlefield scenarios and environmental conditions. The multiphenomenology signal information provides the flexibility to overcome the adverse effects of clutter, countermeasures (both active and passive), illumination, obscurants, target orientation, and weather. It should be noted, however, that the types of sensory information required is dependent on the mission and the operating environment. For instance, a strategic defense sensor operating in space can use (and will need) different types of sensor data than the multifunction sensor employed on an attack helicopter. In fact, the sensor configuration on a helicopter operating in Saudi Arabia may be quite different from one that is deployed to Vietnam. For the purpose of this paper we generalize about the technologies desired for an adaptable, `smart' sensor system. We do not specify a particular mission nor define a specific threat. However, in any case, we can assume the need to fuse sensor signal information in an intelligent processor to provide robust performance in the battlefield environment. 12

  17. Modeling the Spatial Dynamics of International Tuna Fleets

    PubMed Central

    2016-01-01

    We developed an iterative sequential random utility model to investigate the social and environmental determinants of the spatiotemporal decision process of tuna purse-seine fishery fishing effort in the eastern Pacific Ocean. Operations of the fishing gear mark checkpoints in a continuous complex decision-making process. Individual fisher behavior is modeled by identifying diversified choices over decision-space for an entire fishing trip, which allows inclusion of prior and current vessel locations and conditions among the explanatory variables. Among these factors are vessel capacity; departure and arrival port; duration of the fishing trip; daily and cumulative distance travelled, which provides a proxy for operation costs; expected revenue; oceanographic conditions; and tons of fish on board. The model uses a two-step decision process to capture the probability of a vessel choosing a specific fishing region for the first set and the probability of switching to (or staying in) a specific region to fish before returning to its landing port. The model provides a means to anticipate the success of marine resource management, and it can be used to evaluate fleet diversity in fisher behavior, the impact of climate variability, and the stability and resilience of complex coupled human and natural systems. PMID:27537545

  18. Modeling the Spatial Dynamics of International Tuna Fleets.

    PubMed

    Sun, Jenny; Hinton, Michael G; Webster, D G

    2016-01-01

    We developed an iterative sequential random utility model to investigate the social and environmental determinants of the spatiotemporal decision process of tuna purse-seine fishery fishing effort in the eastern Pacific Ocean. Operations of the fishing gear mark checkpoints in a continuous complex decision-making process. Individual fisher behavior is modeled by identifying diversified choices over decision-space for an entire fishing trip, which allows inclusion of prior and current vessel locations and conditions among the explanatory variables. Among these factors are vessel capacity; departure and arrival port; duration of the fishing trip; daily and cumulative distance travelled, which provides a proxy for operation costs; expected revenue; oceanographic conditions; and tons of fish on board. The model uses a two-step decision process to capture the probability of a vessel choosing a specific fishing region for the first set and the probability of switching to (or staying in) a specific region to fish before returning to its landing port. The model provides a means to anticipate the success of marine resource management, and it can be used to evaluate fleet diversity in fisher behavior, the impact of climate variability, and the stability and resilience of complex coupled human and natural systems. PMID:27537545

  19. A mixed fleet transportation system to low Earth orbit

    NASA Technical Reports Server (NTRS)

    1987-01-01

    Based on a provided mission model, this project considered three different classes of launch vehicles for possible use: (1) modifications to the current Space Transportation System, or replacement by a second-generation vehicle using current technology; (2) a heavy-lift cargo vehicle, designed to minimize the cost of bulk cargo to low earth orbit; and (3) an advanced man-rated system incorporating technology anticipated for the year 1995. The mission model provided included commercial, scientific, and military payloads for the years 1990 through 2010. Use of the current Space Transportation System was also permitted in the final fleet sizing analysis. The near-term shuttle group performed trade studies on a number of modifications and variations before selecting a new vehicle design, incorporating a fly-back reusable first stage and reduced-size orbiter. Orbiter payload was limited to 5000 kg (priority items), with up to 25,000 kg of payload carried in a forward payload bay within the nose shroud of the orbiter external tank. This allowed reduction of orbiter size, without significant loss of reusability.

  20. Mixed fleet assessment for on-orbit consumables resupply

    NASA Technical Reports Server (NTRS)

    Eberhardt, Ralph N.; Dominick, Sam M.

    1988-01-01

    Significant increases in the cost effectiveness and operational flexibility of in-space systems can be realized when the capability to replenish consumable fluids and propellants is incorporated into the designs of spacecraft, satellites, and orbiting platforms and laboratories. Reusable tankers are currently being designed for transporting fluids to space. A number of options exist for transporting the fluids and propellants to the space-based user systems. The fluids can be transported to space either in the Shuttle cargo bay or using Expendable Launch Vehicles (ELVs). Resupply can thus be accomplished either from the Shuttle bay, or the tanker can be removed from an ELV and attached to a carrier such as the Orbital Maneuvering Vehicle (OMV) or Orbital Transfer Vehicle (OTV) for transport to the user to be serviced. A third option involves locating the tanker at the Space Station or an unmanned platform as a quasi-permanent servicing facility which returns to the ground for recycling once its tanks have been depleted. This paper documents the impacts of a mixed fleet approach to consumables logistics to orbit. Both storable fluids and propellants, and superfluid helium, are considered. Current modular tanker designs for monopropellants, bipropellants and water for Space Station propulsion are discussed. Trade-offs in superfluid helium tanker sizes, shapes to fit the range of ELVs currently available, and boil-off losses associated with longer-term (greater than 6 months) space-basing, are addressed.

  1. Fleet study evaluation of an advance brake warning system.

    PubMed

    Shinar, D

    2000-01-01

    The advance brake warning system (ABWS) is a mechanism that activates the brake lights in response to a rapid disengagement of the gas pedal, before the driver's foot reaches the brake pedal. Two previous studies showed that (a) such rapid releases of the gas pedal are typically followed by brake activation, and (b) the ABWS can prevent a high percentage of rear-end collisions in which an attentive following driver maintains a headway of 1.0 s or less from the vehicle ahead. In the present study the crash involvement of 764 government cars and light trucks was tracked over an average period of 35 months. The vehicles were matched in pairs--one of each pair with the ABWS and one without it. Data analyses focused on collisions in which the government vehicles were rear-ended. Overall, ABWS-equipped vehicles were not significantly less involved in rear-end collisions. However, an examination of the struck vehicles only showed that the ABWS-equipped vehicles were involved in fewer rear-end collisions per kilometer driven than were the vehicles without the ABWS. In conclusion, despite the theoretical appeal and the results of earlier studies, the fleet study failed to demonstrate that such a system is a cost-effective safety device for the prevention of rear-end crashes. Actual or potential applications include the evaluation of new in-vehicle technologies by a hierarchy of multiple validation studies prior to consideration. PMID:11132809

  2. Managing fleet capacity effectively under second-hand market redistribution.

    PubMed

    Quillérou, Emmanuelle; Roudaut, Nolwenn; Guyader, Olivier

    2013-09-01

    Fishing capacity management policies have been traditionally implemented at national level with national targets for capacity reduction. More recently, capacity management policies have increasingly targeted specific fisheries. French fisheries spatially vary along the French coastline and are associated to specific regions. Capacity management policies, however, ignore the capital mobility associated with second-hand vessel trade between regions. This is not an issue for national policies but could limit the effectiveness of regional capacity management policies. A gravity model and a random-effect Poisson regression model are used to analyze the determinants and spatial extent of the second-hand market in France. This study is based on panel data from the French Atlantic Ocean between 1992 and 2009. The trade flows between trading partners is found to increase with their sizes and to be spatially concentrated. Despite the low trade flows between regions, a net impact analysis shows that fishing capacity is redistributed by the second-hand market to regions on the Channel and Aquitaine from central regions. National capacity management policies (constructions/destructions) have induced a net decrease in regional fleet capacity with varying magnitude across regions. Unless there is a change of policy instruments or their scale of implementation, the operation of the second-hand market decreases the effectiveness of regional capacity management policies in regions on the Channel and Aquitaine. PMID:23288614

  3. High-Mileage Light-Duty Fleet Vehicle Emissions: Their Potentially Overlooked Importance.

    PubMed

    Bishop, Gary A; Stedman, Donald H; Burgard, Daniel A; Atkinson, Oscar

    2016-05-17

    State and local agencies in the United States use activity-based computer models to estimate mobile source emissions for inventories. These models generally assume that vehicle activity levels are uniform across all of the vehicle emission level classifications using the same age-adjusted travel fractions. Recent fuel-specific emission measurements from the SeaTac Airport, Los Angeles, and multi-year measurements in the Chicago area suggest that some high-mileage fleets are responsible for a disproportionate share of the fleet's emissions. Hybrid taxis at the airport show large increases in carbon monoxide, hydrocarbon, and oxide of nitrogen emissions in their fourth year when compared to similar vehicles from the general population. Ammonia emissions from the airport shuttle vans indicate that catalyst reduction capability begins to wane after 5-6 years, 3 times faster than is observed in the general population, indicating accelerated aging. In Chicago, the observed, on-road taxi fleet also had significantly higher emissions and an emissions share that was more than double their fleet representation. When compounded by their expected higher than average mileage accumulation, we estimate that these small fleets (<1% of total) may be overlooked as a significant emission source (>2-5% of fleet emissions). PMID:27137705

  4. Modular sensor network node

    DOEpatents

    Davis, Jesse Harper Zehring; Stark, Jr., Douglas Paul; Kershaw, Christopher Patrick; Kyker, Ronald Dean

    2008-06-10

    A distributed wireless sensor network node is disclosed. The wireless sensor network node includes a plurality of sensor modules coupled to a system bus and configured to sense a parameter. The parameter may be an object, an event or any other parameter. The node collects data representative of the parameter. The node also includes a communication module coupled to the system bus and configured to allow the node to communicate with other nodes. The node also includes a processing module coupled to the system bus and adapted to receive the data from the sensor module and operable to analyze the data. The node also includes a power module connected to the system bus and operable to generate a regulated voltage.

  5. Rolling Deck to Repository (R2R): Big Data and Standard Services for the Fleet Community

    NASA Astrophysics Data System (ADS)

    Arko, R. A.; Carbotte, S. M.; Chandler, C. L.; Smith, S. R.; Stocks, K. I.

    2014-12-01

    The Rolling Deck to Repository (R2R; http://rvdata.us/) program curates underway environmental sensor data from the U.S. academic oceanographic research fleet, ensuring data sets are routinely and consistently documented, preserved in long-term archives, and disseminated to the science community. Currently 25 in-service vessels contribute 7 terabytes of data to R2R each year, acquired from a full suite of geophysical, oceanographic, meteorological, and navigational sensors on over 400 cruises worldwide. To accommodate this large volume and variety of data, R2R has developed highly efficient stewardship procedures. These include scripted "break out" of cruise data packages from each vessel based on standard filename and directory patterns; automated harvest of cruise metadata from the UNOLS Office via Web Services and from OpenXML-based forms submitted by vessel operators; scripted quality assessment routines that calculate statistical summaries and standard ratings for selected data types; adoption of community-standard controlled vocabularies for vessel codes, instrument types, etc, provided by the NERC Vocabulary Server, in lieu of maintaining custom local term lists; and a standard package structure based on the IETF BagIt format for delivering data to long-term archives. Documentation and standard post-field products, including quality-controlled shiptrack navigation data for every cruise, are published in multiple services and formats to satisfy a diverse range of clients. These include Catalog Service for Web (CSW), GeoRSS, and OAI-PMH discovery services via a GeoNetwork portal; OGC Web Map and Feature Services for GIS clients; a citable Digital Object Identifier (DOI) for each dataset; ISO 19115-2 standard geospatial metadata records suitable for submission to long-term archives as well as the POGO global catalog; and Linked Open Data resources with a SPARQL query endpoint for Semantic Web clients. R2R participates in initiatives such as the Ocean Data

  6. Current sensor

    DOEpatents

    Yakymyshyn, Christopher Paul; Brubaker, Michael Allen; Yakymyshyn, Pamela Jane

    2007-01-16

    A current sensor is described that uses a plurality of magnetic field sensors positioned around a current carrying conductor. The sensor can be hinged to allow clamping to a conductor. The current sensor provides high measurement accuracy for both DC and AC currents, and is substantially immune to the effects of temperature, conductor position, nearby current carrying conductors and aging.

  7. Potential for compressed natural gas vehicles in centrally-fueled automobile-, truck-, and bus-fleet applications

    SciTech Connect

    Samsa, M.E.

    1991-06-01

    Two prospective alternative fuel implementation scenarios were created to quantify the potential range of compressed natural gas use in fleet vehicles including fleet automobiles; light-, medium-, and heavy-duty fleet trucks; public transit buses; and school buses. The scenarios are based principally on the clean-fuel fleet vehicle provisions contained in the Clean Air Act Amendments of 1990, the California Low Emission Vehicle Regulations, and the assumed future capability of compressed natural gas to meet various levels of tailpipe emission standards. The potential for using compressed natural gas in fleet vehicle applications varies significantly between the scenarios primarily due to assumption about differences in affected vehicle classes, timing of the regulations, and emission levels. By 2010, the potential for compressed natural gas vehicle use ranges from less than 840 thousand to more than 1.3 million fleet vehicles of all types with corresponding gas demand ranging from 140 to 200 billion cubic feet per year.

  8. Multiple objective optimization for active sensor management

    NASA Astrophysics Data System (ADS)

    Page, Scott F.; Dolia, Alexander N.; Harris, Chris J.; White, Neil M.

    2005-03-01

    The performance of a multi-sensor data fusion system is inherently constrained by the configuration of the given sensor suite. Intelligent or adaptive control of sensor resources has been shown to offer improved fusion performance in many applications. Common approaches to sensor management select sensor observation tasks that are optimal in terms of a measure of information. However, optimising for information alone is inherently sub-optimal as it does not take account of any other system requirements such as stealth or sensor power conservation. We discuss the issues relating to developing a suite of performance metrics for optimising multi-sensor systems and propose some candidate metrics. In addition it may not always be necessary to maximize information gain, in some cases small increases in information gain may take place at the cost of large sensor resource requirements. Additionally, the problems of sensor tasking and placement are usually treated separately, leading to a lack of coherency between sensor management frameworks. We propose a novel approach based on a high level decentralized information-theoretic sensor management architecture that unifies the processes of sensor tasking and sensor placement into a single framework. Sensors are controlled using a minimax multiple objective optimisation approach in order to address probability of target detection, sensor power consumption, and sensor survivability whilst maintaining a target estimation covariance threshold. We demonstrate the potential of the approach through simulation of a multi-sensor, target tracking scenario and compare the results with a single objective information based approach.

  9. Space Weather studies with a fleet of ESA SREM monitors

    NASA Astrophysics Data System (ADS)

    Hajdas, Wojtek; Evans, Hugh; Mohammadzadeh, Ali; Nieminen, Petteri; Desorgher, Laurent; Buehler, Paul; Daly, Eamonn

    2012-07-01

    Reliable observations and studies of Space Weather are based on precisely correlated network of specialized and well calibrated instruments. Such devices are able to provide simultaneously a set of 3D data encompassing large volume of the Earth magnetosphere. The fleet of ESA Standard Radiation Environment Monitors (SREM) is an example of such a network. SREM is a particle detector capable of detection of electrons (E > 500 keV) and protons (E > 8 MeV) with fair spectral and angular resolution. Six of them have been already launched onboard of Proba-1, Rosetta, INTEGRAL, Giove-B, Herschel and Planck missions. As single devices they are able to follow local Space Weather conditions providing accurate measurements of proton and electron spectra. As a network they allow for correlated observations of the radiation environments 3D variability. It includes not only the dynamics of the radiation belts but also propagation of Solar Energetic Particles as well as mapping of Forbusch decreases from coupling of Cosmic Rays and Coronal Mass Ejections. We present the SREM Data Bank open to the public and discuss its main features. Typical examples of the raw data corresponding to the physical phenomena listed above will also be shown. We will also discuss several data conversions algorithms leading to the particle spectra. A comparison between various methods such as simple algorithms, neural network or minimization will be discussed. Several other aspects of the SREM data analysis such as particle identification and separation or flux anisotropy level will also be addressed. Finally we provide short introduction for using of the SREM DB and its main analysis tools.

  10. State and Alternative Fuel Provider Fleets Alternative Compliance; U.S. Department of Energy (DOE), Energy Efficiency & Renewable Energy (EERE)

    SciTech Connect

    2015-08-01

    The final rule of the Energy Policy Act of 2005 and its associated regulations enable covered state and alternative fuel provider fleets to obtain waivers from the alternative fuel vehicle (AFV)-acquisition requirements of Standard Compliance. Under Alternative Compliance, covered fleets instead meet a petroleum-use reduction requirement. This guidance document is designed to help fleets better understand the Alternative Compliance option and successfully complete the waiver application process.

  11. A comparative multi-fleet analysis of socio-economic indicators for fishery management in SE Brazil

    NASA Astrophysics Data System (ADS)

    Gasalla, Maria A.; Rodrigues, Amanda R.; Duarte, Luis F. A.; Rashid Sumaila, U.

    2010-10-01

    One of the problems in an ecosystem approach to fisheries management is the lack of economic analyses which clearly define the performance of different fishing fleets within the system. We describe a comparative multi-fleet analysis of socio-economic indicators applicable for inclusion into ecosystem modeling and management. Based on a survey of different industrial fishing fleets in São Paulo, Southeastern Brazil, an inter-fleet comparison of economic attributes such as investment, fixed costs, effort, labour, sailing-related costs and profits, as well as a set of performance indicators, was conducted. Costs varied between fleets with fuel being the largest component on average, representing almost 37% of total costs. Similarities between fleets were driven by fuel costs, gross incomes and profits. In general, the best economic performance was associated with indicators of profitability and economic efficiency. Bottom-longliners and both surface and bottom-gillnet fleets showed the best economic performance per fishing trip due to their low percentage of variable costs. Purse-seiners and pink-shrimp trawlers had the lowest average rate of return and economic efficiency because of their high variable costs and relatively low catch values, and were considered economically net losers. However, in terms of jobs generated, purse-seiners had the greatest value creating about 49% of total jobs by all fleets. The sea-bob-shrimp fleet had the lowest crew size per vessel but generated the second highest total number of direct jobs (23%), with high economic viability as a whole. The inter-fleet cost and socio-economic performance analysis revealed that additional attention should be given to the poor profitability and overcapacity of fleets, fishing impacts, and open-access related issues, while social indicators may also be considered. This study provides information useful for evaluating different fisheries management scenarios and fleet size optimization in the South

  12. Mitsubishi iMiEV: An Electric Mini-Car in NREL's Advanced Technology Vehicle Fleet (Fact Sheet)

    SciTech Connect

    Not Available

    2011-10-01

    This fact sheet highlights the Mitsubishi iMiEV, an electric mini-car in the advanced technology vehicle fleet at the National Renewable Energy Laboratory (NREL). In support of the U.S. Department of Energy's fast-charging research efforts, NREL engineers are conducting charge and discharge performance testing on the vehicle. NREL's advanced technology vehicle fleet features promising technologies to increase efficiency and reduce emissions without sacrificing safety or comfort. The fleet serves as a technology showcase, helping visitors learn about innovative vehicles that are available today or are in development. Vehicles in the fleet are representative of current, advanced, prototype, and emerging technologies.

  13. Advanced sensors and instrumentation

    NASA Technical Reports Server (NTRS)

    Calloway, Raymond S.; Zimmerman, Joe E.; Douglas, Kevin R.; Morrison, Rusty

    1990-01-01

    NASA is currently investigating the readiness of Advanced Sensors and Instrumentation to meet the requirements of new initiatives in space. The following technical objectives and technologies are briefly discussed: smart and nonintrusive sensors; onboard signal and data processing; high capacity and rate adaptive data acquisition systems; onboard computing; high capacity and rate onboard storage; efficient onboard data distribution; high capacity telemetry; ground and flight test support instrumentation; power distribution; and workstations, video/lighting. The requirements for high fidelity data (accuracy, frequency, quantity, spatial resolution) in hostile environments will continue to push the technology developers and users to extend the performance of their products and to develop new generations.

  14. Tug fleet and ground operations schedules and controls. Volume 1: Executive summary

    NASA Technical Reports Server (NTRS)

    1975-01-01

    This study presents Tug Fleet and Ground Operations Schedules and Controls plan. This plan was developed and optimized out of a combination of individual Tug program phased subplans, special emphasis studies, contingency analyses and sensitivity analyses. The subplans cover the Tug program phases: (1) Tug operational, (2) Interim Upper Stage (IUS)/Tug fleet utilization, (3) and IUS/Tug payload integration, (4) Tug site activation, (5) IUS/Tug transition, (6) Tug acquisition. Resource requirements (facility, GSE, TSE, software, manpower, logistics) are provided in each subplan, as are appropriate Tug processing flows, active and total IUS and Tug fleet requirements, fleet management and Tug payload integration concepts, facility selection recommendations, site activation and IUS to Tug transition requirements. The impact of operational concepts on Tug acquisition is assessed and the impact of operating Tugs out of KSC and WTR is analyzed and presented showing WTR as a delta. Finally, cost estimates for fleet management and ground operations of the DDT&E and operational phases of the Tug program are given.

  15. Intelligent adaptive structures

    NASA Technical Reports Server (NTRS)

    Wada, Ben K.

    1990-01-01

    'Intelligent Adaptive Structures' (IAS) refers to structural systems whose geometric and intrinsic structural characteristics can be automatically changed to meet mission requirements with changing operational scenarios. An IAS is composed of actuators, sensors, and a control logic; these are integrated in a distributed fashion within the elements of the structure. The IAS concepts thus far developed for space antennas and other precision structures should be applicable to civil, marine, automotive, and aeronautical structural systems.

  16. A multiscale forecasting method for power plant fleet management

    NASA Astrophysics Data System (ADS)

    Chen, Hongmei

    In recent years the electric power industry has been challenged by a high level of uncertainty and volatility brought on by deregulation and globalization. A power producer must minimize the life cycle cost while meeting stringent safety and regulatory requirements and fulfilling customer demand for high reliability. Therefore, to achieve true system excellence, a more sophisticated system-level decision-making process with a more accurate forecasting support system to manage diverse and often widely dispersed generation units as a single, easily scaled and deployed fleet system in order to fully utilize the critical assets of a power producer has been created as a response. The process takes into account the time horizon for each of the major decision actions taken in a power plant and develops methods for information sharing between them. These decisions are highly interrelated and no optimal operation can be achieved without sharing information in the overall process. The process includes a forecasting system to provide information for planning for uncertainty. A new forecasting method is proposed, which utilizes a synergy of several modeling techniques properly combined at different time-scales of the forecasting objects. It can not only take advantages of the abundant historical data but also take into account the impact of pertinent driving forces from the external business environment to achieve more accurate forecasting results. Then block bootstrap is utilized to measure the bias in the estimate of the expected life cycle cost which will actually be needed to drive the business for a power plant in the long run. Finally, scenario analysis is used to provide a composite picture of future developments for decision making or strategic planning. The decision-making process is applied to a typical power producer chosen to represent challenging customer demand during high-demand periods. The process enhances system excellence by providing more accurate market

  17. Selection and implementation of a flagship fleet in a locally undervalued region of high endemicity.

    PubMed

    Root-Bernstein, Meredith; Armesto, Juan

    2013-10-01

    Flagships are one conservation education tool. We present a proposed flagship species fleet for environmental education in central Chile. Our methods followed recent flagship guidelines. We present our selection process and a detailed justification for the fleet of flagship species that we selected. Our results are a list of eight flagship species forming a flagship fleet, including two small- and medium-sized mammals, the degu (Octodon degus) and the culpeo fox (Lycalopex culpeaus), two birds, the turca (Pteroptochos megapoidius) and the burrowing owl (Athene cunicularia), the Chilean iguana (Calopistes palluma), the tarantula (Grammostola mollicoma), and two trees, the litre (Lithrea caustica) and the espino (Acacia caven). We then describe how these flagships can be deployed most effectively, describing their audience, effective narrative frames, and modes of presentation. We conclude that general selection rules paired with social science background data allow for an efficient selection process. PMID:23479265

  18. Energy use and taxation policy in the New Zealand car fleet

    SciTech Connect

    Not Available

    1984-02-01

    The report describes the composition of the New Zealand car fleet and the relationship between design factors, fleet composition, vehicle useage and fuel consumption. The indirect energy content of the vehicle and roadway are discussed. Existing and potential Government policy instruments for promoting fuel economy in the car fleet are discussed and evaluated. The report conclusions favor flat rate sales tax on vehicles regardless of engine size together with an appropriate level of petrol tax in preference to taxation that varies with vehicle size or engine capacity. A review of hire purchase regulations is proposed. Prior to publication of this report the Industries Development Commission Plan for the motor vehicle industry was released which proposes changes to the tariff, taxation and credit purchase regime applying to motor vehicles. These changes are summarized.

  19. Assessment of Fleet Inventory for Naval Air Station Whidbey Island. Task 1

    SciTech Connect

    Schey, Stephen; Francfort, Jim

    2015-06-01

    Task 1includes a survey of the inventory of non-tactical fleet vehicles at Naval Air Station Whidbey Island (NASWI) to characterize the fleet. This information and characterization are used to select vehicles for monitoring that takes place during Task 2. This monitoring involves data logging of vehicle operation in order to identify the vehicle’s mission and travel requirements. Individual observations of these selected vehicles provide the basis for recommendations related to PEV adoption. It also identifies whether a battery electric vehicle or plug-in hybrid electric vehicle (collectively referred to as PEVs) can fulfill the mission requirements and provide observations related to placement of PEV charging infrastructure. This report provides the results of the assessments and observations of the current non-tactical fleet, fulfilling the Task 1 requirements.

  20. Integrated operations/payloads/fleet analysis. Volume 5: Mission, capture and operations analysis

    NASA Technical Reports Server (NTRS)

    1971-01-01

    The current baseline mission model consists of the DOD Option B prepared for space transportation system mission analysis and a NASA model prepared for the integrated operations /payloads/ fleet analysis. Changes from the previous mission model are discussed, and additional benefits of the reusable space shuttle system are identified. The methodology and assumptions used in the capture analysis are described, and satellite and launch vehicle traffic models for the current and low cost expendable launch vehicle systems and the reusable space shuttle system are presented. The areas of fleet sizing, limitations and abort modes, system ground support requirements, and ground support systems assessment are covered. Current and extended launch azimuth limitations used for both ETR and WTR are presented for the current and low cost expendable vehicles and also the reusable space shuttle system. The results of a survey of launch support capability for the launch vehicle fleets are reported.

  1. Tug fleet and ground operations schedules and controls. Volume 2: part 1

    NASA Technical Reports Server (NTRS)

    1975-01-01

    This Tug Fleet and Ground Operations Schedules and Controls Study addresses both ground operational data and technical requirements that span the Tug planning phase and operations phase. A similar study covering mission operations (by others) provides the complimentary flight operations details. The two studies provide the planning data requirements, resource allocation, and control milestones for supporting the requirements of the STS program. This Tug Fleet and Ground Operations Schedules and Controls Study incorporates the basic ground operations requirements and concepts provided by previous studies with the interrelationships of the planning, IUS transition, and Tug fleet operations phases. The interrelationships of these phases were studied as a system to optimize overall program benefits and minimize operational risk factors.

  2. Fleet Evaluation and Factory Installation of Aerodynamic Heavy Duty Truck Trailers

    SciTech Connect

    Beck, Jason; Salari, Kambiz; Ortega, Jason; Brown, Andrea

    2013-09-30

    The purpose of DE-EE0001552 was to develop and deploy a combination of trailer aerodynamic devices and low rolling resistance tires that reduce fuel consumption of a class 8 heavy duty tractor-trailer combination vehicle by 15%. There were 3 phases of the project: Phase 1 – Perform SAE Typed 2 track tests with multiple device combinations. Phase 2 – Conduct a fleet evaluation with selected device combination. Phase 3 – Develop the devices required to manufacture the aerodynamic trailer. All 3 phases have been completed. There is an abundance of available trailer devices on the market, and fleets and owner operators have awareness of them and are purchasing them. The products developed in conjunction with this project are at least in their second round of refinement. The fleet test undertaken showed an improvement of 5.5 – 7.8% fuel economy with the devices (This does not include tire contribution).

  3. Pollution prevention opportunity assessment for Sandia National Laboratories/New Mexico's fleet services department.

    SciTech Connect

    Richardson, Anastasia Dawn

    2003-06-01

    This Pollution Prevention Opportunity Assessment (PPOA) was conducted for the Sandia National Laboratories/New Mexico's (SNL/NM) Fleet Services Department between December 2001 and August 2002. This is the third PPOA conducted at Fleet in the last decade. The primary purpose of this PPOA was to review progress of past initiatives and to provide recommendations for future waste reduction measures of hazardous and solid waste streams and increasing the purchase of environmentally friendly products. This report contains a summary of the information collected and analyses performed with recommended options for implementation. The Sandia National Laboratories/New Mexico Pollution Prevention Group will work with SNL/NM's Fleet Services to implement these options.

  4. Fleet Numerical Meteorology and Oceanography Center support for GODAE

    NASA Astrophysics Data System (ADS)

    Dimitriou, D.; Sharfstein, P.; Ignaszewski, M.; Clancy, M.

    2003-04-01

    The U.S. Navy's Fleet Numerical Meteorology and Oceanography Center (FNMOC; see http://www.fnmoc.navy.mil/), located in Monterey, CA, is the lead activity within the U.S. Department of Defense (DoD) for numerical weather prediction and coupled air-sea modeling. FNMOC fulfills this role through means of a suite of sophisticated global and regional meteorological and oceanographic (METOC) models, extending from the top of the atmosphere to the bottom of the ocean, which is supported by one of the world's most complete real-time METOC databases. Fleet Numerical operates around-the-clock, 365 days per year and distributes METOC products to military and civilian users around the world, both ashore and afloat, through a variety of means, including a rapidly growing and innovative use of Web technology. FNMOC's customers include all branches of the Department of Defense (DoD), other government organizations such as the National Weather Service, private companies such as the Weather Channel, a number of colleges and universities, and the general public. FNMOC acquires and processes over 6 million METOC observations per day—creating one of the world's most comprehensive real-time databases of meteorological and oceanographic observations for assimilation into its models. FNMOC employs three primary models, the Navy Operational Global Atmospheric Prediction System (NOGAPS), the Coupled Ocean/Atmosphere Mesoscale Prediction System (COAMPS), and the WaveWatch III model (WW3), along with a number of specialized models and related applications. NOGAPS is a global weather model, driving nearly all other FNMOC models and applications in some fashion. COAMPS is a high-resolution regional model that has proved to be particularly valuable for forecasting weather and ocean conditions in highly complex coastal areas. WW3 is a state-of-the-art ocean wave model that is employed both globally and regionally in support of a wide variety of naval operations. Specialized models support and

  5. Fleet Numerical Meteorology and Oceanography Center support for GODAE

    NASA Astrophysics Data System (ADS)

    Dimitriou, D.; Sharfstein, P.; Ignaszewski, M.; Clancy, M.

    2003-04-01

    The U.S. Navy's Fleet Numerical Meteorology and Oceanography Center (FNMOC; see http://www.fnmoc.navy.mil/), located in Monterey, CA, is the lead activity within the U.S. Department of Defense (DoD) for numerical weather prediction and coupled air-sea modeling. FNMOC fulfills this role through means of a suite of sophisticated global and regional meteorological and oceanographic (METOC) models, extending from the top of the atmosphere to the bottom of the ocean, which is supported by one of the world's most complete real-time METOC databases. Fleet Numerical operates around-the-clock, 365 days per year and distributes METOC products to military and civilian users around the world, both ashore and afloat, through a variety of means, including a rapidly growing and innovative use of Web technology. FNMOC's customers include all branches of the Department of Defense (DoD), other government organizations such as the National Weather Service, private companies such as the Weather Channel, a number of colleges and universities, and the general public. FNMOC acquires and processes over 6 million METOC observations per day—creating one of the world's most comprehensive real-time databases of meteorological and oceanographic observations for assimilation into its models. FNMOC employs three primary models, the Navy Operational Global Atmospheric Prediction System (NOGAPS), the Coupled Ocean/Atmosphere Mesoscale Prediction System (COAMPS), and the WaveWatch III model (WW3), along with a number of specialized models and related applications. NOGAPS is a global weather model, driving nearly all other FNMOC models and applications in some fashion. COAMPS is a high-resolution regional model that has proved to be particularly valuable for forecasting weather and ocean conditions in highly complex coastal areas. WW3 is a state-of-the-art ocean wave model that is employed both globally and regionally in support of a wide variety of naval operations. Specialized models support and

  6. Feature-level sensor fusion

    NASA Astrophysics Data System (ADS)

    Peli, Tamar; Young, Mon; Knox, Robert; Ellis, Kenneth K.; Bennett, Frederick

    1999-03-01

    This paper describes two practical fusion techniques for automatic target cueing that combine features derived from each sensor data ta the object-level. In the hybrid fusion method each of the input sensor data is prescreened before the fusion stage. The cued fusion method assumes that one of the sensors is designated as a primary sensor, and thus ATC is only applied to its input data. If one of the sensors exhibits a higher Pd and/or a lower false alarm rate, it can be selected as the primary sensor. However, if the ground coverage can be segmented to regions in which one of the sensors is known to exhibit better performance, then the cued fusion can be applied locally/adaptively by switching the choice of a primary sensor. Otherwise, the cued fusion is applied both ways and the outputs of each cued mode are combined. Both fusion approaches use a back-end discrimination stage that is applied to a combined feature vector to reduce false alarms. The two fusion processes were applied to spectral and radar sensor data nd were shown to provide substantial false alarm reduction. The approaches are easily extendable to more than two sensors.

  7. Greenhouse gas implications of fleet electrification based on big data-informed individual travel patterns.

    PubMed

    Cai, Hua; Xu, Ming

    2013-08-20

    Environmental implications of fleet electrification highly depend on the adoption and utilization of electric vehicles at the individual level. Past research has been constrained by using aggregated data to assume all vehicles with the same travel pattern as the aggregated average. This neglects the inherent heterogeneity of individual travel behaviors and may lead to unrealistic estimation of environmental impacts of fleet electrification. Using "big data" mining techniques, this research examines real-time vehicle trajectory data for 10,375 taxis in Beijing in one week to characterize the travel patterns of individual taxis. We then evaluate the impact of adopting plug-in hybrid electric vehicles (PHEV) in the taxi fleet on life cycle greenhouse gas emissions based on the characterized individual travel patterns. The results indicate that 1) the largest gasoline displacement (1.1 million gallons per year) can be achieved by adopting PHEVs with modest electric range (approximately 80 miles) with current battery cost, limited public charging infrastructure, and no government subsidy; 2) reducing battery cost has the largest impact on increasing the electrification rate of vehicle mileage traveled (VMT), thus increasing gasoline displacement, followed by diversified charging opportunities; 3) government subsidies can be more effective to increase the VMT electrification rate and gasoline displacement if targeted to PHEVs with modest electric ranges (80 to 120 miles); and 4) while taxi fleet electrification can increase greenhouse gas emissions by up to 115 kiloton CO2-eq per year with the current grid in Beijing, emission reduction of up to 36.5 kiloton CO2-eq per year can be achieved if the fuel cycle emission factor of electricity can be reduced to 168.7 g/km. Although the results are based on a specific public fleet, this study demonstrates the benefit of using large-scale individual-based trajectory data (big data) to better understand environmental implications

  8. Photoelastic sensors

    SciTech Connect

    Kulakov, G.I.

    1985-07-01

    This paper presents the result of a study of photoelastic sensors which makes it possible to explain many mechanical and physical features of the operation of annular photoelastic borehole sensors and to plan ways of utilizing these features for interpreting the sensor readings.

  9. Distributed multi-level supervision to effectively monitor the operations of a fleet of autonomous vehicles in agricultural tasks.

    PubMed

    Conesa-Muñoz, Jesús; Gonzalez-de-Soto, Mariano; Gonzalez-de-Santos, Pablo; Ribeiro, Angela

    2015-01-01

    This paper describes a supervisor system for monitoring the operation of automated agricultural vehicles. The system analyses all of the information provided by the sensors and subsystems on the vehicles in real time and notifies the user when a failure or potentially dangerous situation is detected. In some situations, it is even able to execute a neutralising protocol to remedy the failure. The system is based on a distributed and multi-level architecture that divides the supervision into different subsystems, allowing for better management of the detection and repair of failures. The proposed supervision system was developed to perform well in several scenarios, such as spraying canopy treatments against insects and diseases and selective weed treatments, by either spraying herbicide or burning pests with a mechanical-thermal actuator. Results are presented for selective weed treatment by the spraying of herbicide. The system successfully supervised the task; it detected failures such as service disruptions, incorrect working speeds, incorrect implement states, and potential collisions. Moreover, the system was able to prevent collisions between vehicles by taking action to avoid intersecting trajectories. The results show that the proposed system is a highly useful tool for managing fleets of autonomous vehicles. In particular, it can be used to manage agricultural vehicles during treatment operations. PMID:25751079

  10. Distributed Multi-Level Supervision to Effectively Monitor the Operations of a Fleet of Autonomous Vehicles in Agricultural Tasks

    PubMed Central

    Conesa-Muñoz, Jesús; Gonzalez-de-Soto, Mariano; Gonzalez-de-Santos, Pablo; Ribeiro, Angela

    2015-01-01

    This paper describes a supervisor system for monitoring the operation of automated agricultural vehicles. The system analyses all of the information provided by the sensors and subsystems on the vehicles in real time and notifies the user when a failure or potentially dangerous situation is detected. In some situations, it is even able to execute a neutralising protocol to remedy the failure. The system is based on a distributed and multi-level architecture that divides the supervision into different subsystems, allowing for better management of the detection and repair of failures. The proposed supervision system was developed to perform well in several scenarios, such as spraying canopy treatments against insects and diseases and selective weed treatments, by either spraying herbicide or burning pests with a mechanical-thermal actuator. Results are presented for selective weed treatment by the spraying of herbicide. The system successfully supervised the task; it detected failures such as service disruptions, incorrect working speeds, incorrect implement states, and potential collisions. Moreover, the system was able to prevent collisions between vehicles by taking action to avoid intersecting trajectories. The results show that the proposed system is a highly useful tool for managing fleets of autonomous vehicles. In particular, it can be used to manage agricultural vehicles during treatment operations. PMID:25751079

  11. AVTA Federal Fleet PEV Readiness Data Logging and Characterization Study for NASA Glenn Research Center

    SciTech Connect

    Schey, Stephen; Francfort, Jim

    2014-10-01

    The Advanced Vehicle Testing Activity’s study seeks to collect and evaluate data to validate the utilization of advanced plug-in electric vehicle (PEV) transportation. This report focuses on the NASA Glenn Research Center (GRC) fleet to identify daily operational characteristics of select vehicles and report findings on vehicle and mission characterizations to support the successful introduction of PEVs into the agencies’ fleets. Individual observations of these selected vehicles provide the basis for recommendations related to electric vehicle adoption and whether a battery electric vehicle or plug-in hybrid electric vehicle (collectively referred to as PEVs) can fulfill the mission requirements.

  12. AVTA Federal Fleet PEV Readiness Data Logging and Characterization Study for NASA White Sands Test Facility

    SciTech Connect

    Stephen Schey; Jim Francfort

    2014-10-01

    This report focuses on the NASA White Sands Test Facility (WSTF) fleet to identify daily operational characteristics of select vehicles and report findings on vehicle and mission characterizations to support the successful introduction of plug-in electric vehicles (PEVs) into the agencies’ fleets. Individual observations of these selected vehicles provide the basis for recommendations related to electric vehicle adoption and whether a battery electric vehicle (BEV) or plug-in hybrid electric vehicle (PHEV) (collectively plug-in electric vehicles, or PEVs) can fulfill the mission requirements.

  13. AVTA Federal Fleet PEV Readiness Data Logging and Characterization Study for National Institute of Health

    SciTech Connect

    Schey, Stephen; Francfort, Jim

    2014-11-01

    This report focuses on the National Institute of Health (NIH) fleet to identify daily operational characteristics of select vehicles and report findings on vehicle and mission characterizations to support the successful introduction of plug-in electric vehicles (PEVs) into the agencies’ fleets. Individual observations of these selected vehicles provide the basis for recommendations related to electric vehicle adoption and whether a battery electric vehicle (BEV) or plug-in hybrid electric vehicle (PHEV) (collectively plug-in electric vehicles, or PEVs) can fulfill the mission requirements.

  14. Lessons from cross-fleet/cross-airline observations - Evaluating the impact of CRM/LOFT training

    NASA Technical Reports Server (NTRS)

    Butler, Roy E.

    1991-01-01

    A review is presented of the crew resource management/line oriented flight training (CRM/LOFT) program to help determine the level of standardization across fleets and airlines in the critical area of evaluating crew behavior and performance. One of the goals of the project is to verify that check airmen and LOFT instructors within organizations are evaluating CRM issues consistently and that differences observed between fleets are not a function of idiosyncracies on the part of observers. Attention is given to the research tools for crew evaluation.

  15. MPC and A enhancements for the Murmansk shipping company icebreaker fleet

    SciTech Connect

    Bartoch, O; Bondarev, N; Caskey, D; Forehand, M; Lambert, D; Maltsev, V; O'Brien, M: Gardner, B; Tittemore, G

    1999-07-06

    The United States and the Russian Federation entered into a cooperative agreement in 1994 that resulted in a nuclear weapons non-proliferation program within the United States (US) Department of Energy (DOE) currently known as the Russia/Newly Independent States (NIS) Nuclear Material Security Task Force. In 1996, a project was initiated with the Murmansk Shipping Company to enhance material protection, control, and accounting of highly enriched nuclear fuel assemblies used for the Icebreaker Fleet. The commissioning ceremony for this project is scheduled for August 1999. This paper describes the physical protection, material control, and accounting measures implemented for the Icebreaker Fleet.

  16. Correlating Dynamometer Testing to In-Use Fleet Results of Plug-In Hybrid Electric Vehicles

    SciTech Connect

    John G. Smart; Sera White; Michael Duoba

    2009-05-01

    Standard dynamometer test procedures are currently being developed to determine fuel and electrical energy consumption of plug-in hybrid vehicles (PHEV). To define a repeatable test procedure, assumptions were made about how PHEVs will be driven and charged. This study evaluates these assumptions by comparing results of PHEV dynamometer testing following proposed procedures to actual performance of PHEVs operating in the US Department of Energy’s (DOE) North American PHEV Demonstration fleet. Results show PHEVs in the fleet exhibit a wide range of energy consumption, which is not demonstrated in dynamometer testing. Sources of variation in performance are identified and examined.

  17. 41 CFR 102-34.70 - What do we do with completed calculations of our fleet vehicle acquisitions?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 41 Public Contracts and Property Management 3 2010-07-01 2010-07-01 false What do we do with completed calculations of our fleet vehicle acquisitions? 102-34.70 Section 102-34.70 Public Contracts and... What do we do with completed calculations of our fleet vehicle acquisitions? You must maintain...

  18. A Performance-Oriented Electronics Technician Training Program. V. Final Fleet Follow-Up Evaluation of Graduates.

    ERIC Educational Resources Information Center

    Van Matre, Nicholas H.; Harrigan, Robert J.

    An investigation was made of the job proficiency of the graduates of an experimental job-oriented training program for Electronics Technician (X-ET). This program was designed to train lower-aptitude personnel in a relatively shorter time to assume ET duties in the fleet. The fleet performance capabilities of 51 X-ET's and a matched sample of 43…

  19. 40 CFR 80.62 - Vehicle test procedures to place vehicles in emitter group sub-fleets.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... CFR part 86, with gasoline conforming to requirements detailed in 40 CFR 86.113-90. The results shall... vehicles in emitter group sub-fleets. 80.62 Section 80.62 Protection of Environment ENVIRONMENTAL... Gasoline § 80.62 Vehicle test procedures to place vehicles in emitter group sub-fleets. One of the...

  20. 48 CFR 252.251-7001 - Use of Interagency Fleet Management System (IFMS) vehicles and related services.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... Management System (IFMS) vehicles and related services. 252.251-7001 Section 252.251-7001 Federal Acquisition... Fleet Management System (IFMS) vehicles and related services. As prescribed in 251.205, use the following clause: Use of Interagency Fleet Management System (IFMS) Vehicles and Related Services (DEC...

  1. 48 CFR 252.251-7001 - Use of Interagency Fleet Management System (IFMS) vehicles and related services.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... Management System (IFMS) vehicles and related services. 252.251-7001 Section 252.251-7001 Federal Acquisition... Fleet Management System (IFMS) vehicles and related services. As prescribed in 251.205, use the following clause: Use of Interagency Fleet Management System (IFMS) Vehicles and Related Services (DEC...

  2. 48 CFR 252.251-7001 - Use of Interagency Fleet Management System (IFMS) vehicles and related services.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... Management System (IFMS) vehicles and related services. 252.251-7001 Section 252.251-7001 Federal Acquisition... Fleet Management System (IFMS) vehicles and related services. As prescribed in 251.205, use the following clause: Use of Interagency Fleet Management System (IFMS) Vehicles and Related Services (DEC...

  3. 48 CFR 252.251-7001 - Use of Interagency Fleet Management System (IFMS) vehicles and related services.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... Management System (IFMS) vehicles and related services. 252.251-7001 Section 252.251-7001 Federal Acquisition... Fleet Management System (IFMS) vehicles and related services. As prescribed in 251.205, use the following clause: Use of Interagency Fleet Management System (IFMS) Vehicles and Related Services (DEC...

  4. New system enables fleets to tailor maintenance programs

    SciTech Connect

    Fiscor, S.

    2007-08-15

    The Lubrizol Corporation has developed FluiPak and FluiPak Lite systems to pull engine oils and sample them continuously, helping to maintain mining equipment between oil change intervals. The FluiPak system has a control box, a sensor box and a reserve system. FluiPak Lite is simply a cut-down version of FluiPak. The article explains how the system works to detect in real time oil quality and contaminants and hence optimize drain intervals and also prolong engine component life and reduce waste oil disposal costs. 100 units are currently installed in coal operations. 5 figs., 5 photos.

  5. Phase Adaptation and Correction by Adaptive Optics

    NASA Astrophysics Data System (ADS)

    Tiziani, Hans J.

    2010-04-01

    Adaptive optical elements and systems for imaging or laser beam propagation are used for some time in particular in astronomy, where the image quality is degraded by atmospheric turbulence. In astronomical telescopes a deformable mirror is frequently used to compensate wavefront-errors due to deformations of the large mirror, vibrations as well as turbulence and hence to increase the image quality. In the last few years interesting elements like Spatial Light Modulators, SLM's, such as photorefractive crystals, liquid crystals and micro mirrors and membrane mirrors were introduced. The development of liquid crystals and micro mirrors was driven by data projectors as consumer products. They contain typically a matrix of individually addressable pixels of liquid crystals and flip mirrors respectively or more recently piston mirrors for special applications. Pixel sizes are in the order of a few microns and therefore also appropriate as active diffractive elements in digital holography or miniature masks. Although liquid crystals are mainly optimized for intensity modulation; they can be used for phase modulation. Adaptive optics is a technology for beam shaping and wavefront adaptation. The application of spatial light modulators for wavefront adaptation and correction and defect analysis as well as sensing will be discussed. Dynamic digital holograms are generated with liquid crystal devices (LCD) and used for wavefront correction as well as for beam shaping and phase manipulation, for instance. Furthermore, adaptive optics is very useful to extend the measuring range of wavefront sensors and for the wavefront adaptation in order to measure and compare the shape of high precision aspherical surfaces.

  6. Semantic Sensor Observation Networks in a Billion-Sensor World

    NASA Astrophysics Data System (ADS)

    Bermudez, L. E.; Bogden, P.; Creager, G.; Graybeal, J.

    2008-12-01

    In 2010, there will be 10,000 telemetric devices for every human in the planet (prediction by Ernest and Young). Some of these devices will be collecting data from coastal phenomena. Some will be connected to adaptive sampling systems, which allow observing a phenomenon, forecasting its advance, and triggering of other numerical models, new missions or changes to the sampling frequency of other sensors. These highly sophisticated autonomous and adaptive sensors will help improve the understating of coastal phenomena; however, collaborative arrangements among communities need to happen to be able to interoperate in a world of billions of sensors. Arrangements will allow discovery and sharing of sensor descriptions and understanding and usage of observed data. OOSTethys is an open source collaborative project that helps implement ocean observing system components. Some of these components include sensor interfaces, catalogs of services, and semantic mediators. The OOSTethys team seeks to speed up collaborative arrangements by studying the best standards available, creating easy-to-adopt toolkits, and publishing guides that facilitate the implementation of these components. The interaction of some observing system components, and lessons learned about developing Semantic Sensor Networks using OGC Sensor Observation Services and ontologies, will be discussed.

  7. Intelligent Sensors for Integrated Systems Health Management (ISHM)

    NASA Technical Reports Server (NTRS)

    Schmalzel, John L.

    2008-01-01

    IEEE 1451 Smart Sensors contribute to a number of ISHM goals including cost reduction achieved through: a) Improved configuration management (TEDS); and b) Plug-and-play re-configuration. Intelligent Sensors are adaptation of Smart Sensors to include ISHM algorithms; this offers further benefits: a) Sensor validation. b) Confidence assessment of measurement, and c) Distributed ISHM processing. Space-qualified intelligent sensors are possible a) Size, mass, power constraints. b) Bus structure/protocol.

  8. Adaptive Management

    EPA Science Inventory

    Adaptive management is an approach to natural resource management that emphasizes learning through management where knowledge is incomplete, and when, despite inherent uncertainty, managers and policymakers must act. Unlike a traditional trial and error approach, adaptive managem...

  9. Rolling Deck to Repository (R2R): A "Linked Data" Approach for the U.S. Academic Research Fleet

    NASA Astrophysics Data System (ADS)

    Arko, R. A.; Chandler, C. L.; Clark, P. D.; Milan, A.; Mize, J.

    2011-12-01

    The U.S. academic research fleet is an essential mobile observing platform for ocean science. The NSF-funded Rolling Deck to Repository (R2R) program is working with the fleet community to routinely document, assess, and preserve data from the underway sensor systems on each vessel.
    The R2R facility maintains a master catalog of vessels, instrument systems, operating institutions, cruises, personnel, and data sets. In less than two years, the catalog has grown to over 2,000 cruises including unique identifiers for vessel deployments, project titles, chief scientists, dates, ports, survey targets, and navigation tracks. This master catalog is of great value to peer data systems, ranging from large national data centers to small disciplinary data offices, as an aid in organizing, extending, and quality controlling their own collections and finding related data from authoritative sources.
    R2R breaks with the tradition of stovepipe portals built around complex search interfaces tightly bound to backend databases. Instead, we have adopted a Linked Data approach to publish our catalog content, based on the W3C Resource Description Framework (RDF) and Uniform Resource Identifiers (URIs). Our data model is published as a collection of W3C Simple Knowledge Organization System (SKOS) concepts, mapped to partner vocabularies such as those developed by the Global Change Master Directory (GCMD) and the pan-European SeaDataNet partnership, and our catalog content is published as collections of RDF resources with globally unique and persistent identifiers. The combination of exposing our data model, mapping local terms to community-wide vocabularies, and using reliable identifiers improves interoperability and reduces ambiguity. R2R's metric of success is the degree to which peer data systems routinely harvest and reuse our content.
    R2R is working collaboratively with the NOAA National Data Centers and the NSF-funded Biological and Chemical Oceanography Data

  10. Vehicle fleet emissions of black carbon, polycyclic aromatic hydrocarbons, and other pollutants measured by a mobile laboratory in Mexico City

    NASA Astrophysics Data System (ADS)

    Jiang, M.; Marr, L. C.; Dunlea, E. J.; Herndon, S. C.; Jayne, J. T.; Kolb, C. E.; Knighton, W. B.; Rogers, T. M.; Zavala, M.; Molina, L. T.; Molina, M. J.

    2005-12-01

    Black carbon (BC) and polycyclic aromatic hydrocarbons (PAHs) are of concern due to their effects on climate and health. The main goal of this research is to provide the first estimate of emissions of BC and particle-phase PAHs (PPAHs) from motor vehicles in Mexico City. The emissions of other pollutants including carbon monoxide (CO), oxides of nitrogen (NOx), volatile organic compounds (VOCs), and particulate matter of diameter 2.5 μm and less (PM2.5) are also estimated. As a part of the Mexico City Metropolitan Area field campaign in April 2003 (MCMA-2003), a mobile laboratory was driven throughout the city. The laboratory was equipped with a comprehensive suite of gas and particle analyzers, including an aethalometer that measured BC and a photoionization aerosol sensor that measured PPAHs. While driving through traffic, the mobile lab continuously sampled exhaust plumes from the vehicles around it. We have developed a method of automatically identifying exhaust plumes, which are then used as the basis for calculation of fleet-average emissions. In the approximately 75 h of on-road sampling during the field campaign, we have identified ~30 000 exhaust measurement points that represent a variety of vehicle types and driving conditions. The large sample provides a basis for estimating fleet-average emission factors and thus the emission inventory. Motor vehicles in the Mexico City area are estimated to emit 1700±200 metric tons BC, 57±6 tons PPAHs, 1 190 000±40 000 tons CO, 120 000±3000 tons NOx, 240 000±50 000 tons VOCs, and 4400±400 tons PM2.5 per year, not including cold start emissions. The estimates for CO, NOx, and PPAHs may be low by up to 10% due to the slower response time of analyzers used to measure these species. Compared to the government's official motor vehicle emission inventory for the year 2002, the estimates for CO, NOx, VOCs, and PM2.5 are 38% lower, 23% lower, 27% higher, and 25% higher, respectively. The distributions of emission

  11. Bioinspired vision sensors with hyperacuity

    NASA Astrophysics Data System (ADS)

    Barrett, Steven F.; Wright, Cameron H. G.

    2011-04-01

    Musca domestica, the common house fly, possesses a powerful vision system that exhibits features such as fast, analog, parallel operation and motion hyperacuity -- the ability to detect the movement of objects at far better resolution than predicted by their photoreceptor spacing. Researchers at the Wyoming Information, Signal Processing, and Robotics (WISPR) Laboratory have investigated these features for over a decade to develop an analog sensor inspired by the fly. Research efforts have been divided into electrophysiology; mathematical, optical and MATLAB based sensor modeling; physical sensor development; and applications. This paper will provide an in depth review of recent key results in some of these areas including development of a multiple, light adapting cartridge based sensor constructed on both a planar and co-planar surface using off-the-shelf components. Both a photodiode-based approach and a fiber based sensor will be discussed. Applications in UAV obstacle avoidance, long term building monitoring and autonomous robot navigation are also discussed.

  12. Flexible Temperature Sensors on Fibers

    PubMed Central

    Sibinski, Maciej; Jakubowska, Malgorzata; Sloma, Marcin

    2010-01-01

    The aim of this paper is to present research dedicated to the elaboration of novel, miniaturized flexible temperature sensors for textronic applications. Examined sensors were manufactured on a single yarn, which ensures their high flexibility and good compatibility with textiles. Stable and linear characteristics were obtained by special technological process and applied temperature profiles. As a thermo-sensitive materials the innovative polymer compositions filled with multiwalled carbon nanotubes were used. Elaborated material was adapted to printing and dip-coating techniques to produce NTC composites. Nanotube sensors were free from tensometric effect typical for other carbon-polymer sensor, and demonstrated TCR of 0.13%/K. Obtained temperature sensors, compatible with textile structure, can be applied in rapidly developing smart textiles and be used for health and protections purposes. PMID:22163634

  13. 41 CFR 102-34.335 - How do I submit information to the General Services Administration (GSA) for the Federal Fleet...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... information to the General Services Administration (GSA) for the Federal Fleet Report (FFR)? 102-34.335... (Continued) FEDERAL MANAGEMENT REGULATION PERSONAL PROPERTY 34-MOTOR VEHICLE MANAGEMENT Federal Fleet Report... Fleet Report (FFR)? (a) Annually, agencies must submit to GSA the information needed to produce the...

  14. 40 CFR 86.1710-99 - Fleet average non-methane organic gas exhaust emission standards for light-duty vehicles and...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 19 2010-07-01 2010-07-01 false Fleet average non-methane organic gas....1710-99 Fleet average non-methane organic gas exhaust emission standards for light-duty vehicles and light light-duty trucks. (a) Fleet average NMOG standards and compliance. (1) Each manufacturer...

  15. 40 CFR 86.1710-99 - Fleet average non-methane organic gas exhaust emission standards for light-duty vehicles and...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 20 2012-07-01 2012-07-01 false Fleet average non-methane organic gas....1710-99 Fleet average non-methane organic gas exhaust emission standards for light-duty vehicles and... follows: Table R99-15—Fleet Average Non-Methane Organic Gas Standards (g/mi) for Light-Duty Vehicles...

  16. 40 CFR 86.1710-99 - Fleet average non-methane organic gas exhaust emission standards for light-duty vehicles and...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 20 2013-07-01 2013-07-01 false Fleet average non-methane organic gas....1710-99 Fleet average non-methane organic gas exhaust emission standards for light-duty vehicles and... follows: Table R99-15—Fleet Average Non-Methane Organic Gas Standards (g/mi) for Light-Duty Vehicles...

  17. 40 CFR 86.1710-99 - Fleet average non-methane organic gas exhaust emission standards for light-duty vehicles and...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 19 2011-07-01 2011-07-01 false Fleet average non-methane organic gas....1710-99 Fleet average non-methane organic gas exhaust emission standards for light-duty vehicles and... follows: Table R99-15—Fleet Average Non-Methane Organic Gas Standards (g/mi) for Light-Duty Vehicles...

  18. Adaptive Full Aperture Wavefront Sensor Study

    NASA Technical Reports Server (NTRS)

    Robinson, William G.

    1997-01-01

    This grant and the work described was in support of a Seven Segment Demonstrator (SSD) and review of wavefront sensing techniques proposed by the Government and Contractors for the Next Generation Space Telescope (NGST) Program. A team developed the SSD concept. For completeness, some of the information included in this report has also been included in the final report of a follow-on contract (H-27657D) entitled "Construction of Prototype Lightweight Mirrors". The original purpose of this GTRI study was to investigate how various wavefront sensing techniques might be most effectively employed with large (greater than 10 meter) aperture space based telescopes used for commercial and scientific purposes. However, due to changes in the scope of the work performed on this grant and in light of the initial studies completed for the NGST program, only a portion of this report addresses wavefront sensing techniques. The wavefront sensing techniques proposed by the Government and Contractors for the NGST were summarized in proposals and briefing materials developed by three study teams including NASA Goddard Space Flight Center, TRW, and Lockheed-Martin. In this report, GTRI reviews these approaches and makes recommendations concerning the approaches. The objectives of the SSD were to demonstrate functionality and performance of a seven segment prototype array of hexagonal mirrors and supporting electromechanical components which address design issues critical to space optics deployed in large space based telescopes for astronomy and for optics used in spaced based optical communications systems. The SSD was intended to demonstrate technologies which can support the following capabilities: Transportation in dense packaging to existing launcher payload envelopes, then deployable on orbit to form a space telescope with large aperture. Provide very large (greater than 10 meters) primary reflectors of low mass and cost. Demonstrate the capability to form a segmented primary or quaternary mirror into a quasi-continuous surface with individual subapertures phased so that near diffraction limited imaging in the visible wavelength region is achieved. Continuous compensation of optical wavefront due to perturbations caused by imperfections, natural disturbances, and equipment induced vibrations/deflections to provide near diffraction limited imaging performance in the visible wavelength region. Demonstrate the feasibility of fabricating such systems with reduced mass and cost compared to past approaches.

  19. Modeling, simulation & optimization of the landing craft air cushion fleet readiness.

    SciTech Connect

    Engi, Dennis

    2006-10-01

    The Landing Craft Air Cushion is a high-speed, over-the-beach, fully amphibious landing craft capable of carrying a 60-75 ton payload. The LCAC fleet can serve to transport weapons systems, equipment, cargo and personnel from ship to shore and across the beach. This transport system is an integral part of our military arsenal and, as such, its readiness is an important consideration for our national security. Further, the best way to expend financial resources that have been allocated to maintain this fleet is a critical Issue. There is a clear coupling between the measure of Fleet Readiness as defined by the customer for this project and the information that is provided by Sandia's ProOpta methodology. Further, there is a richness in the data that provides even more value to the analyst. This report provides an analytic framework for understanding the connection between Fleet Readiness and the output provided by Sandia's ProOpta software. Further, this report highlights valuable information that can also be made available using the ProOpta output and concepts from basic probability theory. Finally, enabling assumptions along with areas that warrant consideration for further study are identified.

  20. Alternative fuels for vehicles fleet demonstration program. Final report, volume 2: Appendices

    SciTech Connect

    1997-06-01

    The Alternative Fuels for Vehicles Fleet Demonstration Program (AFV-FDP) was a multiyear effort to collect technical data for use in determining the costs and benefits of alternative-fuel vehicles (AFVs) in typical applications in New York State. This report, Volume 2, includes 13 appendices to Volume 1 that expand upon issues raised therein. Volume 1 provides: (1) Information about the purpose and scope of the AFV-FDP; (2) A summary of AFV-FDP findings organized on the basis of vehicle type and fuel type; (3) A short review of the status of AFV technology development, including examples of companies in the State that are active in developing AFVs and AFV components; and (4) A brief overview of the status of AFV deployment in the State. Volume 3 provides expanded reporting of AFV-FDP technical details, including the complete texts of the brochure Garage Guidelines for Alternative Fuels and the technical report Fleet Experience Survey Report, plus an extensive glossary of AFV terminology. The appendices cover a wide range of issues including: emissions regulations in New York State; production and health effects of ozone; vehicle emissions and control systems; emissions from heavy-duty engines; reformulated gasoline; greenhouse gases; production and characteristics of alternative fuels; the Energy Policy Act of 1992; the Clean Fuel Fleet Program; garage design guidelines for alternative fuels; surveys of fleet managers using alternative fuels; taxes on conventional and alternative fuels; and zero-emission vehicle technology.