WorldWideScience

Sample records for randomly deployed sensor

  1. On the hop count statistics for randomly deployed wireless sensor networks

    NARCIS (Netherlands)

    Dulman, S.O.; Rossi, M.; Havinga, Paul J.M.; Zorzi, M.

    2006-01-01

    In this paper we focus on exploiting the information provided by a generally accepted and largely ignored hypothesis (the random deployment of the nodes of an ad hoc or wireless sensor network) to design improved networking protocols. Specifically, we derive the relationship between the number of

  2. Remotely deployable aerial inspection using tactile sensors

    Science.gov (United States)

    MacLeod, C. N.; Cao, J.; Pierce, S. G.; Sullivan, J. C.; Pipe, A. G.; Dobie, G.; Summan, R.

    2014-02-01

    For structural monitoring applications, the use of remotely deployable Non-Destructive Evaluation (NDE) inspection platforms offer many advantages, including improved accessibility, greater safety and reduced cost, when compared to traditional manual inspection techniques. The use of such platforms, previously reported by researchers at the University Strathclyde facilitates the potential for rapid scanning of large areas and volumes in hazardous locations. A common problem for both manual and remote deployment approaches lies in the intrinsic stand-off and surface coupling issues of typical NDE probes. The associated complications of these requirements are obviously significantly exacerbated when considering aerial based remote inspection and deployment, resulting in simple visual techniques being the preferred sensor payload. Researchers at Bristol Robotics Laboratory have developed biomimetic tactile sensors modelled on the facial whiskers (vibrissae) of animals such as rats and mice, with the latest sensors actively sweeping their tips across the surface in a back and forth motion. The current work reports on the design and performance of an aerial inspection platform and the suitability of tactile whisking sensors to aerial based surface monitoring applications.

  3. Self-deployable mobile sensor networks for on-demand surveillance

    Science.gov (United States)

    Miao, Lidan; Qi, Hairong; Wang, Feiyi

    2005-05-01

    This paper studies two interconnected problems in mobile sensor network deployment, the optimal placement of heterogeneous mobile sensor platforms for cost-efficient and reliable coverage purposes, and the self-organizable deployment. We first develop an optimal placement algorithm based on a "mosaicked technology" such that different types of mobile sensors form a mosaicked pattern uniquely determined by the popularity of different types of sensor nodes. The initial state is assumed to be random. In order to converge to the optimal state, we investigate the swarm intelligence (SI)-based sensor movement strategy, through which the randomly deployed sensors can self-organize themselves to reach the optimal placement state. The proposed algorithm is compared with the random movement and the centralized method using performance metrics such as network coverage, convergence time, and energy consumption. Simulation results are presented to demonstrate the effectiveness of the mosaic placement and the SI-based movement.

  4. A Novel Deployment Scheme Based on Three-Dimensional Coverage Model for Wireless Sensor Networks

    Science.gov (United States)

    Xiao, Fu; Yang, Yang; Wang, Ruchuan; Sun, Lijuan

    2014-01-01

    Coverage pattern and deployment strategy are directly related to the optimum allocation of limited resources for wireless sensor networks, such as energy of nodes, communication bandwidth, and computing power, and quality improvement is largely determined by these for wireless sensor networks. A three-dimensional coverage pattern and deployment scheme are proposed in this paper. Firstly, by analyzing the regular polyhedron models in three-dimensional scene, a coverage pattern based on cuboids is proposed, and then relationship between coverage and sensor nodes' radius is deduced; also the minimum number of sensor nodes to maintain network area's full coverage is calculated. At last, sensor nodes are deployed according to the coverage pattern after the monitor area is subdivided into finite 3D grid. Experimental results show that, compared with traditional random method, sensor nodes number is reduced effectively while coverage rate of monitor area is ensured using our coverage pattern and deterministic deployment scheme. PMID:25045747

  5. EDITORIAL Wireless sensor networks: design for real-life deployment and deployment experiences Wireless sensor networks: design for real-life deployment and deployment experiences

    Science.gov (United States)

    Gaura, Elena; Roedig, Utz; Brusey, James

    2010-12-01

    Wireless sensor networks (WSNs) are among the most promising technologies of the new millennium. The opportunities afforded by being able to program networks of small, lightweight, low-power, computation- and bandwidth-limited nodes have attracted a large community of researchers and developers. However, the unique set of capabilities offered by the technology produces an exciting but complex design space, which is often difficult to negotiate in an application context. Deploying sensing physical environments produces its own set of challenges, and can push systems into failure modes, thus revealing problems that can be difficult to discover or reproduce in simulation or the laboratory. Sustained efforts in the area of wireless networked sensing over the last 15 years have resulted in a large number of theoretical developments, substantial practical achievements, and a wealth of lessons for the future. It is clear that in order to bridge the gap between (on the one hand) visions of very large scale, autonomous, randomly deployed networks and (on the other) the actual performance of fielded systems, we need to view deployment as an essential component in the process of developing sensor networks: a process that includes hardware and software solutions that serve specific applications and end-user needs. Incorporating deployment into the design process reveals a new and different set of requirements and considerations, whose solutions require innovative thinking, multidisciplinary teams and strong involvement from end-user communities. This special feature uncovers and documents some of the hurdles encountered and solutions offered by experimental scientists when deploying and evaluating wireless sensor networks in situ, in a variety of well specified application scenarios. The papers specifically address issues of generic importance for WSN system designers: (i) data quality, (ii) communications availability and quality, (iii) alternative, low-energy sensing

  6. An efficient genetic algorithm for maximum coverage deployment in wireless sensor networks.

    Science.gov (United States)

    Yoon, Yourim; Kim, Yong-Hyuk

    2013-10-01

    Sensor networks have a lot of applications such as battlefield surveillance, environmental monitoring, and industrial diagnostics. Coverage is one of the most important performance metrics for sensor networks since it reflects how well a sensor field is monitored. In this paper, we introduce the maximum coverage deployment problem in wireless sensor networks and analyze the properties of the problem and its solution space. Random deployment is the simplest way to deploy sensor nodes but may cause unbalanced deployment and therefore, we need a more intelligent way for sensor deployment. We found that the phenotype space of the problem is a quotient space of the genotype space in a mathematical view. Based on this property, we propose an efficient genetic algorithm using a novel normalization method. A Monte Carlo method is adopted to design an efficient evaluation function, and its computation time is decreased without loss of solution quality using a method that starts from a small number of random samples and gradually increases the number for subsequent generations. The proposed genetic algorithms could be further improved by combining with a well-designed local search. The performance of the proposed genetic algorithm is shown by a comparative experimental study. When compared with random deployment and existing methods, our genetic algorithm was not only about twice faster, but also showed significant performance improvement in quality.

  7. Autonomous Deployment and Restoration of Sensor Network using Mobile Robots

    Directory of Open Access Journals (Sweden)

    Tsuyoshi Suzuki

    2010-09-01

    Full Text Available This paper describes an autonomous deployment and restoration of a Wireless Sensor Network (WSN using mobile robots. The authors have been developing an information-gathering system using mobile robots and WSNs in underground spaces in post-disaster environments. In our system, mobile robots carry wireless sensor nodes (SN and deploy them into the environment while measuring Received Signal Strength Indication (RSSI values to ensure communication, thereby enabling the WSN to be deployed and restored autonomously. If the WSN is disrupted, mobile robots restore the communication route by deploying additional or alternate SNs to suitable positions. Utilizing the proposed method, a mobile robot can deploy a WSN and gather environmental information via the WSN. Experimental results using a verification system equipped with a SN deployment and retrieval mechanism are presented.

  8. Autonomous Deployment and Restoration of Sensor Network using Mobile Robots

    Directory of Open Access Journals (Sweden)

    Tsuyoshi Suzuki

    2010-06-01

    Full Text Available This paper describes an autonomous deployment and restoration of a Wireless Sensor Network (WSN using mobile robots. The authors have been developing an information-gathering system using mobile robots and WSNs in underground spaces in post-disaster environments. In our system, mobile robots carry wireless sensor nodes (SN and deploy them into the environment while measuring Received Signal Strength Indication (RSSI values to ensure communication, thereby enabling the WSN to be deployed and restored autonomously. If the WSN is disrupted, mobile robots restore the communication route by deploying additional or alternate SNs to suitable positions. Utilizing the proposed method, a mobile robot can deploy a WSN and gather environmental information via the WSN. Experimental results using a verification system equipped with a SN deployment and retrieval mechanism are presented.

  9. Sensor Deployment for Air Pollution Monitoring Using Public Transportation System

    OpenAIRE

    Yu, James J. Q.; Li, Victor O. K.; Lam, Albert Y. S.

    2015-01-01

    Air pollution monitoring is a very popular research topic and many monitoring systems have been developed. In this paper, we formulate the Bus Sensor Deployment Problem (BSDP) to select the bus routes on which sensors are deployed, and we use Chemical Reaction Optimization (CRO) to solve BSDP. CRO is a recently proposed metaheuristic designed to solve a wide range of optimization problems. Using the real world data, namely Hong Kong Island bus route data, we perform a series of simulations an...

  10. A Deployment Scheme Based Upon Virtual Force for Directional Sensor Networks

    Directory of Open Access Journals (Sweden)

    Chiu-Kuo Liang

    2015-11-01

    Full Text Available A directional sensor network is composed of many directional sensor nodes. Unlike conventional omni-directional sensors that always have an omni-angle of sensing range; directional sensors may have a limited angle of sensing range due to technical constraints or cost considerations. Area coverage is still an essential issue in a directional sensor network. In this paper, we study the area coverage problem in directional sensor networks with mobile sensors, which can move to the correct places to get high coverage. We present distributed self-deployment schemes of mobile sensors. After sensors are randomly deployed, each sensor calculates its next new location to move in order to obtain a better coverage than previous one. The locations of sensors are adjusted round by round so that the coverage is gradually improved. Based on the virtual force of the directional sensors, we design a scheme, namely Virtual force scheme. Simulation results show the effectiveness of our scheme in term of the coverage improvement.

  11. Weight-Aware Sensor Deployment in Wireless Sensor Networks for Smart Cities

    Directory of Open Access Journals (Sweden)

    Mingshan Xie

    2018-01-01

    Full Text Available During the construction of wireless sensor networks (WSNs for smart cities, a preliminary survey of the relative criticalness within the monitored area can be performed. It is a challenge for deterministic sensor deployment to balance the tradeoff of sensing reliability and cost. In this paper, based on the sensing accuracy of the sensor, we establish a reliability model of the sensing area which is divided into sensing grids, and different weights are allocated to those grids. We employ a practical evaluation criterion using seesaw mapping for determining the weights of sensing grids. We further formulate and solve an optimization problem for maximizing the trust degree of the WSNs. With our proposed method, the efficient deployment of sensors can be realized. Simulation results show that our proposed deployment strategy can achieve higher trust degree with reduced sensor deployment cost and lower number of sensors at a certain miss probability threshold.

  12. Context-Aware Local Optimization of Sensor Network Deployment

    Directory of Open Access Journals (Sweden)

    Meysam Argany

    2015-07-01

    Full Text Available Wireless sensor networks are increasingly used for tracking and monitoring dynamic phenomena in urban and natural areas. Spatial coverage is an important issue in sensor networks in order to fulfill the needs of sensing applications. Optimization methods are widely used to efficiently distribute sensor nodes in the network to achieve a desired level of coverage. Most of the existing algorithms do not consider the characteristics of the real environment in the optimization process. In this paper, we propose the integration of contextual information in optimization algorithms to improve sensor network coverage. First, we investigate the implication of contextual information in sensor networks. Then, a conceptual framework for local context-aware sensor network deployment optimization method is introduced and related algorithms are presented in detail. Finally, several experiments are carried out to evaluate the validity of the proposed method. The results obtained from these experiments show the effectiveness of our approach in different contextual situations.

  13. Deployment of Wireless Sensor Networks in Crop Storages

    DEFF Research Database (Denmark)

    Juul, Jakob Pilegaard; Green, Ole; Jacobsen, Rune Hylsberg

    2015-01-01

    of a wireless sensor network based system that provides continuous, automatic, and up-to-date information on a crop storage, while presenting the data in an easily accessible manner, is also described. The design decisions, challenges, and practical experiences from real-world large scale deployment...

  14. Low Cost and Flexible UAV Deployment of Sensors

    DEFF Research Database (Denmark)

    Sørensen, Lars Yndal; Jacobsen, Lars Toft; Hansen, John Paulin

    2017-01-01

    -collection needs. The main contribution is the extensible architecture for modularized airborne sensor deployment and real-time data visualisation. Our open-source Android application provides data collection, flight path definition and map tools. Total cost of the system is below 800 dollars. The flexibility...

  15. Deployment-based lifetime optimization model for homogeneous Wireless Sensor Network under retransmission.

    Science.gov (United States)

    Li, Ruiying; Liu, Xiaoxi; Xie, Wei; Huang, Ning

    2014-12-10

    Sensor-deployment-based lifetime optimization is one of the most effective methods used to prolong the lifetime of Wireless Sensor Network (WSN) by reducing the distance-sensitive energy consumption. In this paper, data retransmission, a major consumption factor that is usually neglected in the previous work, is considered. For a homogeneous WSN, monitoring a circular target area with a centered base station, a sensor deployment model based on regular hexagonal grids is analyzed. To maximize the WSN lifetime, optimization models for both uniform and non-uniform deployment schemes are proposed by constraining on coverage, connectivity and success transmission rate. Based on the data transmission analysis in a data gathering cycle, the WSN lifetime in the model can be obtained through quantifying the energy consumption at each sensor location. The results of case studies show that it is meaningful to consider data retransmission in the lifetime optimization. In particular, our investigations indicate that, with the same lifetime requirement, the number of sensors needed in a non-uniform topology is much less than that in a uniform one. Finally, compared with a random scheme, simulation results further verify the advantage of our deployment model.

  16. Wireless Sensor Network Deployment for Monitoring Wildlife Passages

    Science.gov (United States)

    Garcia-Sanchez, Antonio-Javier; Garcia-Sanchez, Felipe; Losilla, Fernando; Kulakowski, Pawel; Garcia-Haro, Joan; Rodríguez, Alejandro; López-Bao, José-Vicente; Palomares, Francisco

    2010-01-01

    Wireless Sensor Networks (WSNs) are being deployed in very diverse application scenarios, including rural and forest environments. In these particular contexts, specimen protection and conservation is a challenge, especially in natural reserves, dangerous locations or hot spots of these reserves (i.e., roads, railways, and other civil infrastructures). This paper proposes and studies a WSN based system for generic target (animal) tracking in the surrounding area of wildlife passages built to establish safe ways for animals to cross transportation infrastructures. In addition, it allows target identification through the use of video sensors connected to strategically deployed nodes. This deployment is designed on the basis of the IEEE 802.15.4 standard, but it increases the lifetime of the nodes through an appropriate scheduling. The system has been evaluated for the particular scenario of wildlife monitoring in passages across roads. For this purpose, different schemes have been simulated in order to find the most appropriate network operational parameters. Moreover, a novel prototype, provided with motion detector sensors, has also been developed and its design feasibility demonstrated. Original software modules providing new functionalities have been implemented and included in this prototype. Finally, main performance evaluation results of the whole system are presented and discussed in depth. PMID:22163601

  17. Wireless Sensor Network Deployment for Monitoring Wildlife Passages

    Directory of Open Access Journals (Sweden)

    José-Vicente López-Bao

    2010-08-01

    Full Text Available Wireless Sensor Networks (WSNs are being deployed in very diverse application scenarios, including rural and forest environments. In these particular contexts, specimen protection and conservation is a challenge, especially in natural reserves, dangerous locations or hot spots of these reserves (i.e., roads, railways, and other civil infrastructures. This paper proposes and studies a WSN based system for generic target (animal tracking in the surrounding area of wildlife passages built to establish safe ways for animals to cross transportation infrastructures. In addition, it allows target identification through the use of video sensors connected to strategically deployed nodes. This deployment is designed on the basis of the IEEE 802.15.4 standard, but it increases the lifetime of the nodes through an appropriate scheduling. The system has been evaluated for the particular scenario of wildlife monitoring in passages across roads. For this purpose, different schemes have been simulated in order to find the most appropriate network operational parameters. Moreover, a novel prototype, provided with motion detector sensors, has also been developed and its design feasibility demonstrated. Original software modules providing new functionalities have been implemented and included in this prototype. Finally, main performance evaluation results of the whole system are presented and discussed in depth.

  18. Software as a service approach to sensor simulation software deployment

    Science.gov (United States)

    Webster, Steven; Miller, Gordon; Mayott, Gregory

    2012-05-01

    Traditionally, military simulation has been problem domain specific. Executing an exercise currently requires multiple simulation software providers to specialize, deploy, and configure their respective implementations, integrate the collection of software to achieve a specific system behavior, and then execute for the purpose at hand. This approach leads to rigid system integrations which require simulation expertise for each deployment due to changes in location, hardware, and software. Our alternative is Software as a Service (SaaS) predicated on the virtualization of Night Vision Electronic Sensors (NVESD) sensor simulations as an exemplary case. Management middleware elements layer self provisioning, configuration, and integration services onto the virtualized sensors to present a system of services at run time. Given an Infrastructure as a Service (IaaS) environment, enabled and managed system of simulations yields a durable SaaS delivery without requiring user simulation expertise. Persistent SaaS simulations would provide on demand availability to connected users, decrease integration costs and timelines, and benefit the domain community from immediate deployment of lessons learned.

  19. ZERO: Probabilistic Routing for Deploy and Forget Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Jose Carlos Pacho

    2010-09-01

    Full Text Available As Wireless Sensor Networks are being adopted by industry and agriculture for large-scale and unattended deployments, the need for reliable and energy-conservative protocols become critical. Physical and Link layer efforts for energy conservation are not mostly considered by routing protocols that put their efforts on maintaining reliability and throughput. Gradient-based routing protocols route data through most reliable links aiming to ensure 99% packet delivery. However, they suffer from the so-called ”hot spot” problem. Most reliable routes waste their energy fast, thus partitioning the network and reducing the area monitored. To cope with this ”hot spot” problem we propose ZERO a combined approach at Network and Link layers to increase network lifespan while conserving reliability levels by means of probabilistic load balancing techniques.

  20. A Nodes Deployment Algorithm in Wireless Sensor Network Based on Distribution

    Directory of Open Access Journals (Sweden)

    Song Yuli

    2014-07-01

    Full Text Available Wireless sensor network coverage is a basic problem of wireless sensor network. In this paper, we propose a wireless sensor network node deployment algorithm base on distribution in order to form an efficient wireless sensor network. The iteratively greedy algorithm is used in this paper to choose priority nodes into active until the entire network is covered by wireless sensor nodes, the whole network to multiply connected. The simulation results show that the distributed wireless sensor network node deployment algorithm can form a multiply connected wireless sensor network.

  1. A Multiobjective Fuzzy Inference System based Deployment Strategy for a Distributed Mobile Sensor Network

    Directory of Open Access Journals (Sweden)

    Amol P. Bhondekar

    2010-03-01

    Full Text Available Sensor deployment scheme highly governs the effectiveness of distributed wireless sensor network. Issues such as energy conservation and clustering make the deployment problem much more complex. A multiobjective Fuzzy Inference System based strategy for mobile sensor deployment is presented in this paper. This strategy gives a synergistic combination of energy capacity, clustering and peer-to-peer deployment. Performance of our strategy is evaluated in terms of coverage, uniformity, speed and clustering. Our algorithm is compared against a modified distributed self-spreading algorithm to exhibit better performance.

  2. On Efficient Deployment of Wireless Sensors for Coverage and Connectivity in Constrained 3D Space.

    Science.gov (United States)

    Wu, Chase Q; Wang, Li

    2017-10-10

    Sensor networks have been used in a rapidly increasing number of applications in many fields. This work generalizes a sensor deployment problem to place a minimum set of wireless sensors at candidate locations in constrained 3D space to k -cover a given set of target objects. By exhausting the combinations of discreteness/continuousness constraints on either sensor locations or target objects, we formulate four classes of sensor deployment problems in 3D space: deploy sensors at Discrete/Continuous Locations (D/CL) to cover Discrete/Continuous Targets (D/CT). We begin with the design of an approximate algorithm for DLDT and then reduce DLCT, CLDT, and CLCT to DLDT by discretizing continuous sensor locations or target objects into a set of divisions without sacrificing sensing precision. Furthermore, we consider a connected version of each problem where the deployed sensors must form a connected network, and design an approximation algorithm to minimize the number of deployed sensors with connectivity guarantee. For performance comparison, we design and implement an optimal solution and a genetic algorithm (GA)-based approach. Extensive simulation results show that the proposed deployment algorithms consistently outperform the GA-based heuristic and achieve a close-to-optimal performance in small-scale problem instances and a significantly superior overall performance than the theoretical upper bound.

  3. A Power Balance Aware Wireless Charger Deployment Method for Complete Coverage in Wireless Rechargeable Sensor Networks

    Directory of Open Access Journals (Sweden)

    Tu-Liang Lin

    2016-08-01

    Full Text Available Traditional sensor nodes are usually battery powered, and the limited battery power constrains the overall lifespan of the sensors. Recently, wireless power transmission technology has been applied in wireless sensor networks (WSNs to transmit wireless power from the chargers to the sensor nodes and solve the limited battery power problem. The combination of wireless sensors and wireless chargers forms a new type of network called wireless rechargeable sensor networks (WRSNs. In this research, we focus on how to effectively deploy chargers to maximize the lifespan of a network. In WSNs, the sensor nodes near the sink consume more power than nodes far away from the sink because of frequent data forwarding. This important power unbalanced factor has not been considered, however, in previous charger deployment research. In this research, a power balance aware deployment (PBAD method is proposed to address the power unbalance in WRSNs and to design the charger deployment with maximum charging efficiency. The proposed deployment method is effectively aware of the existence of the sink node that would cause unbalanced power consumption in WRSNs. The simulation results show that the proposed PBAD algorithm performs better than other deployment methods, and fewer chargers are deployed as a result.

  4. A Polygon Model for Wireless Sensor Network Deployment with Directional Sensing Areas

    Science.gov (United States)

    Wu, Chun-Hsien; Chung, Yeh-Ching

    2009-01-01

    The modeling of the sensing area of a sensor node is essential for the deployment algorithm of wireless sensor networks (WSNs). In this paper, a polygon model is proposed for the sensor node with directional sensing area. In addition, a WSN deployment algorithm is presented with topology control and scoring mechanisms to maintain network connectivity and improve sensing coverage rate. To evaluate the proposed polygon model and WSN deployment algorithm, a simulation is conducted. The simulation results show that the proposed polygon model outperforms the existed disk model and circular sector model in terms of the maximum sensing coverage rate. PMID:22303159

  5. Deployment of 802.15.4 Sensor Networks for C4ISR Operations

    National Research Council Canada - National Science Library

    Ngo, Damian N

    2006-01-01

    .... The objective of this thesis is to focus on the deployment issues of WSNs. In addition, this thesis assesses the optimal configurations and environment that enables the sensor networks to thrive in a C4ISR environment...

  6. Lessons learned on solar powered wireless sensor network deployments in urban, desert environments

    KAUST Repository

    Dehwah, Ahmad H.; Mousa, Mustafa; Claudel, Christian G.

    2015-01-01

    The successful deployment of a large scale solar powered wireless sensor network in an urban, desert environment is a very complex task. Specific cities of such environments cause a variety of operational problems, ranging from hardware faults

  7. A figure control sensor for the Large Deployable Reflector (LDR)

    Science.gov (United States)

    Bartman, R.; Dubovitsky, S.

    1988-01-01

    A sensing and control system is required to maintain high optical figure quality in a segmented reflector. Upon detecting a deviation of the segmented surface from its ideal form, the system drives segment mounted actuators to realign the individual segments and thereby return the surface to its intended figure. When the reflector is in use, a set of figure sensors will determine positions of a number of points on the back surface of each of the reflector's segments, each sensor being assigned to a single point. By measuring the positional deviations of these points from previously established nominal values, the figure sensors provide the control system with the information required to maintain the reflector's optical figure. The optical lever, multiple wavelength interferometer, and electronic capacitive sensor, the most promising technologies for the development of the figure sensor, are illustrated. It is concluded that to select a particular implementation of the figure sensors, performance requirement will be refined and relevant technologies investigated further.

  8. Extending the lifetime of wireless sensor network with partial SDN deployment

    Directory of Open Access Journals (Sweden)

    S. Tomovic

    2016-06-01

    Full Text Available Energy efficiency is one of the key requirements in Wireless Sensor Networks (WSNs. In order to optimize energy usage at sensor nodes, this paper proposes a new network architecture that relies on concepts of Software Defined Networking (SDN. Since SDN is a relatively new technology, originally envisioned for wired networks, it cannot be expected to get immediately and completely adopted in WSN domain, regardless of potential benefits. For this reason, we consider incremental SDN deployment where SDN nodes coexist with traditional sensor nodes, and propose a new routing algorithm for SDN controller that prolongs the WSN lifetime even when a small percentage of SDN nodes is deployed.

  9. Optimum wireless sensor deployment scheme for structural health monitoring: a simulation study

    International Nuclear Information System (INIS)

    Liu, Chengyin; Fang, Kun; Teng, Jun

    2015-01-01

    With the rapid advancements in smart sensing technology and wireless communication technology, the wireless sensor network (WSN) offers an alternative solution to structural health monitoring (SHM). In WSNs, dense deployment of wireless nodes aids the identification of structural dynamic characteristics, while data transmission is a significant issue since wireless channels typically have a lower bandwidth and a limited power supply. This paper provides a wireless sensor deployment optimization scheme for SHM, in terms of both energy consumption and modal identification accuracy. A spherical energy model is established to formulate the energy consumption within a WSN. The optimal number of sensors and their locations are obtained through solving a multi-objective function with weighting factors on energy consumption and modal identification accuracy using a genetic algorithm (GA). Simulation and comparison results with traditional sensor deployment methods demonstrate the efficiency of the proposed optimization scheme. (paper)

  10. Pure random search for ambient sensor distribution optimisation in a smart home environment.

    Science.gov (United States)

    Poland, Michael P; Nugent, Chris D; Wang, Hui; Chen, Liming

    2011-01-01

    Smart homes are living spaces facilitated with technology to allow individuals to remain in their own homes for longer, rather than be institutionalised. Sensors are the fundamental physical layer with any smart home, as the data they generate is used to inform decision support systems, facilitating appropriate actuator actions. Positioning of sensors is therefore a fundamental characteristic of a smart home. Contemporary smart home sensor distribution is aligned to either a) a total coverage approach; b) a human assessment approach. These methods for sensor arrangement are not data driven strategies, are unempirical and frequently irrational. This Study hypothesised that sensor deployment directed by an optimisation method that utilises inhabitants' spatial frequency data as the search space, would produce more optimal sensor distributions vs. the current method of sensor deployment by engineers. Seven human engineers were tasked to create sensor distributions based on perceived utility for 9 deployment scenarios. A Pure Random Search (PRS) algorithm was then tasked to create matched sensor distributions. The PRS method produced superior distributions in 98.4% of test cases (n=64) against human engineer instructed deployments when the engineers had no access to the spatial frequency data, and in 92.0% of test cases (n=64) when engineers had full access to these data. These results thus confirmed the hypothesis.

  11. Gone to Dust: Building and Deploying a Particle Sensor

    Science.gov (United States)

    Fibiger, D. L.; Wiley, C.

    2015-12-01

    Using an Arduino microcontroller board and a commercially available optical particle sensor, we built particulate sensors and walked them around the school to evaluate where the highest levels of particulate matter (PM) were. As part of the Earth Explorers outreach program in Boulder, Colorado, we worked with a group of middle school students to build and use these sensors. The students were in 6th and 7th grade, and we met three times. Once to introduce the scientist and science they will be working on, the second time to actually do the hand-on project and, finally, to review what they learned in the experiment. Arduino is an open-source electronics platform that is simple to program, using the Arduino programming language. There are example codes available for the particle sensors and they are easy to adapt to different uses. The sensor setup is straightforward and was built into a small footprint on a plastic toy brick with a handle for easy use. We pre-loaded the Arduino board with the necessary software, but had the students wire the sensor, Arduino, indicator lights and battery together and attached them to the brick. This gave the students an opportunity to learn about electricity and wiring, in addition to air pollution. The sensor is not calibrated or quantitative, so only qualitative data was obtained. The qualitative data, however, was sufficient to allow the students to make predictions and test their hypotheses. While most of the students predicted outside, near the parking lot would have the highest PM levels, they learned that indoor pollution can be much higher, particularly in carpeted areas.

  12. Lessons learned on solar powered wireless sensor network deployments in urban, desert environments

    KAUST Repository

    Dehwah, Ahmad H.

    2015-05-01

    The successful deployment of a large scale solar powered wireless sensor network in an urban, desert environment is a very complex task. Specific cities of such environments cause a variety of operational problems, ranging from hardware faults to operational challenges, for instance due to the high variability of solar energy availability. Even a seemingly functional sensor network created in the lab does not guarantee reliable long term operation, which is absolutely necessary given the cost and difficulty of accessing sensor nodes in urban environments. As part of a larger traffic flow wireless sensor network project, we conducted several deployments in the last two years to evaluate the long-term performance of solar-powered urban wireless sensor networks in a desert area. In this article, we share our experiences in all domains of sensor network operations, from the conception of hardware to post-deployment analysis, including operational constraints that directly impact the software that can be run. We illustrate these experiences using numerous experimental results, and present multiple unexpected operational problems as well as some possible solutions to address them. We also show that current technology is far from meeting all operational constraints for these demanding applications, in which sensor networks are to operate for years to become economically appealing.

  13. Parking Sensing and Information System: Sensors, Deployment, and Evaluation

    OpenAIRE

    Chen, Xiao; Zhen; Qian; Rajagopal, Ram; Stiers, Todd; Flores, Christopher; Kavaler, Robert; Williams III, Floyd

    2017-01-01

    This paper describes a smart parking sensing and information system that disseminates the parking availability information for public users in a cost-effective and efficient manner. The hardware framework of the system is built on advanced wireless sensor networks and cloud service over the Internet, and the system is highly scalable. The parking information provided to the users is set in the form of occupancy rates and expected cruising time. Both are obtained from our analytical algorithm ...

  14. Rule-Based vs. Behavior-Based Self-Deployment for Mobile Wireless Sensor Networks.

    Science.gov (United States)

    Urdiales, Cristina; Aguilera, Francisco; González-Parada, Eva; Cano-García, Jose; Sandoval, Francisco

    2016-07-07

    In mobile wireless sensor networks (MWSN), nodes are allowed to move autonomously for deployment. This process is meant: (i) to achieve good coverage; and (ii) to distribute the communication load as homogeneously as possible. Rather than optimizing deployment, reactive algorithms are based on a set of rules or behaviors, so nodes can determine when to move. This paper presents an experimental evaluation of both reactive deployment approaches: rule-based and behavior-based ones. Specifically, we compare a backbone dispersion algorithm with a social potential fields algorithm. Most tests are done under simulation for a large number of nodes in environments with and without obstacles. Results are validated using a small robot network in the real world. Our results show that behavior-based deployment tends to provide better coverage and communication balance, especially for a large number of nodes in areas with obstacles.

  15. Cross Deployment Networking and Systematic Performance Analysis of Underwater Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Zhengxian Wei

    2017-07-01

    Full Text Available Underwater wireless sensor networks (UWSNs have become a new hot research area. However, due to the work dynamics and harsh ocean environment, how to obtain an UWSN with the best systematic performance while deploying as few sensor nodes as possible and setting up self-adaptive networking is an urgent problem that needs to be solved. Consequently, sensor deployment, networking, and performance calculation of UWSNs are challenging issues, hence the study in this paper centers on this topic and three relevant methods and models are put forward. Firstly, the normal body-centered cubic lattice to cross body-centered cubic lattice (CBCL has been improved, and a deployment process and topology generation method are built. Then most importantly, a cross deployment networking method (CDNM for UWSNs suitable for the underwater environment is proposed. Furthermore, a systematic quar-performance calculation model (SQPCM is proposed from an integrated perspective, in which the systematic performance of a UWSN includes coverage, connectivity, durability and rapid-reactivity. Besides, measurement models are established based on the relationship between systematic performance and influencing parameters. Finally, the influencing parameters are divided into three types, namely, constraint parameters, device performance and networking parameters. Based on these, a networking parameters adjustment method (NPAM for optimized systematic performance of UWSNs has been presented. The simulation results demonstrate that the approach proposed in this paper is feasible and efficient in networking and performance calculation of UWSNs.

  16. Assessing the Performance of a Network of Low Cost Particulate Matter Sensors Deployed in Sacramento, California

    Science.gov (United States)

    Mukherjee, A. D.; Brown, S. G.; McCarthy, M. C.

    2017-12-01

    A new generation of low cost air quality sensors have the potential to provide valuable information on the spatial-temporal variability of air pollution - if the measurements have sufficient quality. This study examined the performance of a particulate matter sensor model, the AirBeam (HabitatMap Inc., Brooklyn, NY), over a three month period in the urban environment of Sacramento, California. Nineteen AirBeam sensors were deployed at a regulatory air monitoring site collocated with meteorology measurements and as a local network over an 80 km2 domain in Sacramento, CA. This study presents the methodology to evaluate the precision, accuracy, and reliability of the sensors over a range of meteorological and aerosol conditions. The sensors demonstrated a robust degree of precision during collocated measurement periods (R2 = 0.98 - 0.99) and a moderate degree of correlation against a Beta Attenuation Monitor PM2.5 monitor (R2 0.6). A normalization correction is applied during the study period so that each AirBeam sensor in the network reports a comparable value. The role of the meteorological environment on the accuracy of the sensor measurements is investigated, along with the possibility of improving the measurements through a meteorology weighted correction. The data quality of the network of sensors is examined, and the spatial variability of particulate matter through the study domain derived from the sensor network is presented.

  17. Miniaturized robotically deployed sensor systems for in-situ characterization of hazardous waste

    International Nuclear Information System (INIS)

    Fischer, G.J.

    1996-01-01

    A series of ''MiniLab'' end effectors are currently being designed for robotic deployment in hazardous areas such as waste storage tanks at Idaho National Engineering Laboratories (INEL) and Oak Ridge National Laboratory (ORNL). These MiniLabs will be the first ever multichannel hazardous waste characterization end effectors deployed in underground high level waste storage tanks. They consist of a suite of chemical, radiological, and physical properties sensors integrated into a compact package mounted on the end of a robotic arm and/or vehicle. Most of the sensors are commercially available thus reducing the overall cost of design and maintenance. Sensor configurations can be customized depending on site/customer needs. This paper will address issues regarding the cost of field sampling verses MiniLab in-situ measurements and a brief background of the Light Duty utility Arm (LDUA) program. Topics receiving in depth attention will include package size parameters/constraints, design specifications, and investigations of currently available sensor technology. Sensors include radiological, gas, chemical, electrolytic, visual, temperature, and ranging. The effects of radiation on the life of the systems/sensors will also be discussed. Signal processing, control, display, and data acquisition methods will be described. The paper will conclude with an examination of possible applications for MiniLabs

  18. MULTI-SENSOR NETWORK FOR LANDSLIDES SIMULATION AND HAZARD MONITORING - DESIGN AND DEPLOYMENT

    Directory of Open Access Journals (Sweden)

    H. Wu

    2012-08-01

    Full Text Available This paper describes a newly developed multi-sensor network system for landslide and hazard monitoring. Landslide hazard is one of the most destructive natural disasters, which has severely affected human safety, properties and infrastructures. We report the results of designing and deploying the multi-sensor network, based on the simulated landslide model, to monitor typical landslide areas and with a goal to predict landslide hazard and mitigate damages. The integration and deployment of the prototype sensor network were carried out in an experiment area at Tongji University in Shanghai. In order to simulate a real landslide, a contractible landslide body is constructed in the experiment area by 7m*1.5m. Then, some different kind of sensors, such as camera, GPS, crackmeter, accelerometer, laser scanning system, inclinometer, etc., are installed near or in the landslide body. After the sensors are powered, continuous sampling data will be generated. With the help of communication method, such as GPRS, and certain transport devices, such as iMesh and 3G router, all the sensor data will be transported to the server and stored in Oracle. These are the current results of an ongoing project of the center. Further research results will be updated and presented in the near future.

  19. ­The Carnegie Quick Deploy Box (QDB) for use with broadband and intermediate period sensors

    Science.gov (United States)

    Wagner, L. S.; Roman, D.; Bartholomew, T.; Golden, S.; Schleigh, B.

    2017-12-01

    Recent data processing advances have increased the call for dense recordings of teleseismic data. However, traditional broadband field installations typically comprise 1) a sensor vault 2) a field box to hold the recording and power systems, and 3) a solar panel mount. The construction of these installations is time consuming and requires bulky construction materials, limiting the number of stations that can be installed from a single vehicle without repeated trips to a storage facility. Depending on the deployment location, watertight containers for both vault and field box can be difficult to find, resulting in a loss of data due to flooding. Recent technological improvements have made possible the direct burial of sensors (no vault required) and a reduction in the size of the solar panels needed to run a station. With support from the Brinson Foundation, we take advantage of these advances to create a field box/shipping container that will greatly simplify these types of seismic deployments. The goal of the Carnegie Quick Deploy Box (QDB) is to have everything needed for an intermediate period station install (except battery and shovel) contained in a single box for shipment, and to be able to leave everything (except the shovel) in that box when the station is deployed. The box is small enough ( 13"x13"x21") and lightweight enough (< 35 lbs) to be checked as airline luggage. The solar panel mount can be attached securely to the top of the box, but it can also be pole mounted with U-bolts or hose clamps. The sensor can be direct-buried. The sensor cable and solar panel cable plug into watertight bulkhead-fitted plugs on the outside of the box that are in turn plugged into the digitizer and power regulator inside the box. Our prototype boxes (Pelican Cases) have proved watertight when submerged for days. This equipment has been tested in Alaska in winter and Nicaragua in summer without failure due to flooding or power. The cost for parts for a single box (not

  20. Evaluation of Deployment Challenges of Wireless Sensor Networks at Signalized Intersections

    Directory of Open Access Journals (Sweden)

    Leyre Azpilicueta

    2016-07-01

    Full Text Available With the growing demand of Intelligent Transportation Systems (ITS for safer and more efficient transportation, research on and development of such vehicular communication systems have increased considerably in the last years. The use of wireless networks in vehicular environments has grown exponentially. However, it is highly important to analyze radio propagation prior to the deployment of a wireless sensor network in such complex scenarios. In this work, the radio wave characterization for ISM 2.4 GHz and 5 GHz Wireless Sensor Networks (WSNs deployed taking advantage of the existence of traffic light infrastructure has been assessed. By means of an in-house developed 3D ray launching algorithm, the impact of topology as well as urban morphology of the environment has been analyzed, emulating the realistic operation in the framework of the scenario. The complexity of the scenario, which is an intersection city area with traffic lights, vehicles, people, buildings, vegetation and urban environment, makes necessary the channel characterization with accurate models before the deployment of wireless networks. A measurement campaign has been conducted emulating the interaction of the system, in the vicinity of pedestrians as well as nearby vehicles. A real time interactive application has been developed and tested in order to visualize and monitor traffic as well as pedestrian user location and behavior. Results show that the use of deterministic tools in WSN deployment can aid in providing optimal layouts in terms of coverage, capacity and energy efficiency of the network.

  1. Process of 3D wireless decentralized sensor deployment using parsing crossover scheme

    Directory of Open Access Journals (Sweden)

    Albert H.R. Ko

    2015-07-01

    Full Text Available A Wireless Sensor Networks (WSN usually consists of numerous wireless devices deployed in a region of interest, each able to collect and process environmental information and communicate with neighboring devices. It can thus be regarded as a Multi-Agent System for territorial security, where individual agents cooperate with each other to avoid duplication of effort and to exploit other agent’s capacities. The problem of sensor deployment becomes non-trivial when we consider environmental factors, such as terrain elevations. Due to the fact that all sensors are homogeneous, the chromosomes that encode sensor positions are actually interchangeable, and conventional crossover schemes such as uniform crossover would cause some redundancy as well as over-concentration in certain specific geographical area. We propose a Parsing Crossover Scheme that intends to reduce redundancy and ease geographical concentration pattern in an effort to facilitate the search. The proposed parsing crossover method demonstrates better performances than those of uniform crossover under different terrain irregularities.

  2. A Movement-Assisted Deployment of Collaborating Autonomous Sensors for Indoor and Outdoor Environment Monitoring

    Directory of Open Access Journals (Sweden)

    Ewa Niewiadomska-Szynkiewicz

    2016-09-01

    Full Text Available Using mobile robots or unmanned vehicles to assist optimal wireless sensors deployment in a working space can significantly enhance the capability to investigate unknown environments. This paper addresses the issues of the application of numerical optimization and computer simulation techniques to on-line calculation of a wireless sensor network topology for monitoring and tracking purposes. We focus on the design of a self-organizing and collaborative mobile network that enables a continuous data transmission to the data sink (base station and automatically adapts its behavior to changes in the environment to achieve a common goal. The pre-defined and self-configuring approaches to the mobile-based deployment of sensors are compared and discussed. A family of novel algorithms for the optimal placement of mobile wireless devices for permanent monitoring of indoor and outdoor dynamic environments is described. They employ a network connectivity-maintaining mobility model utilizing the concept of the virtual potential function for calculating the motion trajectories of platforms carrying sensors. Their quality and utility have been justified through simulation experiments and are discussed in the final part of the paper.

  3. A Movement-Assisted Deployment of Collaborating Autonomous Sensors for Indoor and Outdoor Environment Monitoring.

    Science.gov (United States)

    Niewiadomska-Szynkiewicz, Ewa; Sikora, Andrzej; Marks, Michał

    2016-09-14

    Using mobile robots or unmanned vehicles to assist optimal wireless sensors deployment in a working space can significantly enhance the capability to investigate unknown environments. This paper addresses the issues of the application of numerical optimization and computer simulation techniques to on-line calculation of a wireless sensor network topology for monitoring and tracking purposes. We focus on the design of a self-organizing and collaborative mobile network that enables a continuous data transmission to the data sink (base station) and automatically adapts its behavior to changes in the environment to achieve a common goal. The pre-defined and self-configuring approaches to the mobile-based deployment of sensors are compared and discussed. A family of novel algorithms for the optimal placement of mobile wireless devices for permanent monitoring of indoor and outdoor dynamic environments is described. They employ a network connectivity-maintaining mobility model utilizing the concept of the virtual potential function for calculating the motion trajectories of platforms carrying sensors. Their quality and utility have been justified through simulation experiments and are discussed in the final part of the paper.

  4. On Prolonging Network Lifetime through Load-Similar Node Deployment in Wireless Sensor Networks

    Science.gov (United States)

    Li, Qiao-Qin; Gong, Haigang; Liu, Ming; Yang, Mei; Zheng, Jun

    2011-01-01

    This paper is focused on the study of the energy hole problem in the Progressive Multi-hop Rotational Clustered (PMRC)-structure, a highly scalable wireless sensor network (WSN) architecture. Based on an analysis on the traffic load distribution in PMRC-based WSNs, we propose a novel load-similar node distribution strategy combined with the Minimum Overlapping Layers (MOL) scheme to address the energy hole problem in PMRC-based WSNs. In this strategy, sensor nodes are deployed in the network area according to the load distribution. That is, more nodes shall be deployed in the range where the average load is higher, and then the loads among different areas in the sensor network tend to be balanced. Simulation results demonstrate that the load-similar node distribution strategy prolongs network lifetime and reduces the average packet latency in comparison with existing nonuniform node distribution and uniform node distribution strategies. Note that, besides the PMRC structure, the analysis model and the proposed load-similar node distribution strategy are also applicable to other multi-hop WSN structures. PMID:22163809

  5. Building-in-Briefcase: A Rapidly-Deployable Environmental Sensor Suite for the Smart Building.

    Science.gov (United States)

    Weekly, Kevin; Jin, Ming; Zou, Han; Hsu, Christopher; Soyza, Chris; Bayen, Alexandre; Spanos, Costas

    2018-04-29

    A building’s environment has profound influence on occupant comfort and health. Continuous monitoring of building occupancy and environment is essential to fault detection, intelligent control, and building commissioning. Though many solutions for environmental measuring based on wireless sensor networks exist, they are not easily accessible to households and building owners who may lack time or technical expertise needed to set up a system and get quick and detailed overview of environmental conditions. Building-in-Briefcase (BiB) is a portable sensor network platform that is trivially easy to deploy in any building environment. Once the sensors are distributed, the environmental data is collected and communicated to the BiB router via the Transmission Control Protocol/Internet Protocol (TCP/IP) and WiFi technology, which then forwards the data to the central database securely over the internet through a 3G radio. The user, with minimal effort, can access the aggregated data and visualize the trends in real time on the BiB web portal. Paramount to the adoption and continued operation of an indoor sensing platform is battery lifetime. This design has achieved a multi-year lifespan by careful selection of components, an efficient binary communications protocol and data compression. Our BiB sensor is capable of collecting a rich set of environmental parameters, and is expandable to measure others, such as CO 2 . This paper describes the power characteristics of BiB sensors and their occupancy estimation and activity recognition functionality. We have demonstrated large-scale deployment of BiB throughout Singapore. Our vision is that, by monitoring thousands of buildings through BiB, it would provide ample research opportunities and opportunities to identify ways to improve the building environment and energy efficiency.

  6. Deployment Algorithms of Wireless Sensor Networks for Near-surface Underground Oil and Gas Pipeline Monitoring

    Directory of Open Access Journals (Sweden)

    Hua-Ping YU

    2014-07-01

    Full Text Available Oil and gas pipelines are the infrastructure of national economic development. Deployment problem of wireless underground sensor networks (WUSN for oil and gas pipeline systems is a fundamental problem. This paper firstly analyzed the wireless channel characteristics and energy consumption model in near-surface underground soil, and then studied the spatial structure of oil and gas pipelines and introduced the three-layer system structure of WUSN for oil and gas pipelines monitoring. Secondly, the optimal deployment strategy in XY plane and XZ plane which were projected from three-dimensional oil and gas pipeline structure was analyzed. Thirdly, the technical framework of using kinetic energy of the fluid in pipelines to recharge sensor nodes and partition strategy for energy consumption balance based on the wireless communication technology of magnetic induction waveguide were proposed, which can effectively improve the energy performance and connectivity of the network, and provide theoretical guidance and practical basis for the monitoring of long oil and gas pipeline network, the city tap water pipe network and sewage pipe network.

  7. Field evaluation of a direct push deployed sensor probe for vertical soil water content profiling

    Science.gov (United States)

    Vienken, Thomas; Reboulet, Ed; Leven, Carsten; Kreck, Manuel; Zschornack, Ludwig; Dietrich, Peter

    2015-04-01

    Reliable high-resolution information about vertical variations in soil water content, i.e. total porosity in the saturated zone, is essential for flow and transport predictions within the subsurface. However, porosity measurements are often associated with high efforts and high uncertainties, e.g. caused by soil disturbance during sampling or sensor installation procedures. In hydrogeological practice, commonly applied tools for the investigation of vertical soil water content distribution include gravimetric laboratory analyses of soil samples and neutron probe measurements. A yet less well established technique is the use of direct push-deployed sensor probes. Each of these methods is associated with inherent advantages and limitations due to their underlying measurement principles and operation modes. The presented study describes results of a joint field evaluation of the individual methods under different depositional and hydrogeological conditions with special focus on the performance on the direct push-deployed water content profiler. Therefore, direct push-profiling results from three different test sites are compared with results obtained from gravimetric analysis of soil cores and neutron probe measurements. In direct comparison, the applied direct push-based sensor probe proved to be a suitable alternative for vertical soil water content profiling to neutron probe technology, and, in addition, proved to be advantageous over gravimetric analysis in terms vertical resolution and time efficiency. Results of this study identify application-specific limitations of the methods and thereby highlight the need for careful data evaluation, even though neutron probe measurements and gravimetric analyses of soil samples are well established techniques (see Vienken et al. 2013). Reference: Vienken, T., Reboulet, E., Leven, C., Kreck, M., Zschornack, L., Dietrich, P., 2013. Field comparison of selected methods for vertical soil water content profiling. Journal of

  8. Realtime Delivery of Alarms and Key Observables in a Deployed Hydrological Sensor Network

    Science.gov (United States)

    Marshall, I. W.; Price, M. C.; Li, H.; Boyd, N.; Boult, S.

    2007-12-01

    It has widely [1-3] been proposed that sensor networks are a good solution for environmental monitoring. However, this application presents a number of major challenges for current technology. In particular environmental science involves the study of coupled non-equilibrium dynamic processes that generate time series with non-stationary means and strongly dependent variables and which operate in the presence of large amounts of noise/interference (thermal, chemical and biological) and multiple quasi-periodic forcing factors (diurnal cycles, tides, etc). This typically means that any analysis must be based on large data samples obtained at multiple scales of space and time. In addition the areas of interest are large, relatively inaccessible and typically extremely hostile to electronic instrumentation. Our analysis of these factors has encouraged us to focus on this list of generic requirements; a) Node lifetime (between visits) should be 1 yr or greater b) Communication range should be ~250m c) Nodes should be portable, unobtrusive, low cost, etc. d) Networks are expected to be sparse since areas of interest are large and budgets are small However, the characteristics of each environment, the dominant processes operating in it and the measurements that are of interest are sufficiently different that the design of an appropriate sensor network solution is normally most determined by site specific constraints. Most importantly the opportunities for exploiting contextual correlation to disambiguate observations and improve the maintenance and robustness of a deployed sensor network are always site specific. We will describe the design and initial deployment of a hydrological sensor network we are developing to assess the hydro-dynamics of surface water drainage into Great Crowden Brook in the Peak District (UK). The complete network will observe soil moisture, temperature and rainfall on a number of transects across the valley, and will also investigate water quality

  9. Deployment of wireless sensor network in pyrochemical processing of metallic fuels

    International Nuclear Information System (INIS)

    Baghyalakshmi, D.; Shrikrishnan, T.S.; Ebenezer, Jemimah; Madhusoodanan, K.; Satya Murty, S.A.V.; Vannia Perumal, S.; Venkatesh, P.; Prabhakara Reddy, B.

    2016-01-01

    With the advent of wireless sensor networking technology, industries started adapting the wireless monitoring systems in phases to measure and control various process parameters. To test the feasibility for implementing Wireless Sensor Network to measure the potentials of an electrochemical cell and the temperatures of actinide drawdown process at Pyrochemical process studies laboratory, at Chemistry Group, IGCAR, Kalpakkam, experiments have been carried out. An experimental setup with two Wireless Sensor Networking nodes has been deployed inside argon atmosphere glove boxes. The Electrorefining studies on U and U based alloys and the studies on actinide recovery from the electrolyte salt in actinide drawdown process are carried out in the glove box. The WSN measuring system was tested and validated by measuring the potentials of an electrochemical cell and the temperatures of actinide drawdown process. The WSN system is proposed to be installed in the hot cells of the Chemistry Group where irradiated U-Zr fuel is reprocessed. This paper briefs the need for remote measuring in pyrochemical reprocessing and validation of the remote signals by measuring the potentials of an electrochemical cell and the temperatures of the actinide draw down process. (author)

  10. Recent advances of mid-infrared compact, field deployable sensors: principles and applications

    Science.gov (United States)

    Tittel, Frank; Gluszek, Aleksander; Hudzikowski, Arkadiusz; Dong, Lei; Li, Chunguang; Patimisco, Pietro; Sampaolo, Angelo; Spagnolo, Vincenzo; Wojtas, Jacek

    2016-04-01

    The recent development of compact interband cascade lasers(ICLs) and quantum cascade lasers (QCLs) based trace gas sensors will permit the targeting of strong fundamental rotational-vibrational transitions in the mid-infrared which are one to two orders of magnitude more intense than transitions in the overtone and combination bands in the near-infrared. This has led to the design and fabrication of mid-infrared compact, field deployable sensors for use in the petrochemical industry, environmental monitoring and atmospheric chemistry. Specifically, the spectroscopic detection and monitoring of four molecular species, methane (CH4) [1], ethane (C2H6), formaldehyde (H2CO) [2] and hydrogen sulphide (H2S) [3] will be described. CH4, C2H6 and H2CO can be detected using two detection techniques: mid-infrared tunable laser absorption spectroscopy (TDLAS) using a compact multi-pass gas cell and quartz enhanced photoacoustic spectroscopy (QEPAS). Both techniques utilize state-of-the-art mid-IR, continuous wave (CW), distributed feedback (DFB) ICLs and QCLs. TDLAS was performed with an ultra-compact 54.6m effective optical path length innovative spherical multipass gas cell capable of 435 passes between two concave mirrors separated by 12.5 cm. QEPAS used a small robust absorption detection module (ADM) which consists of a quartz tuning fork (QTF), two optical windows, gas inlet/outlet ports and a low noise frequency pre-amplifier. Wavelength modulation and second harmonic detection were employed for spectral data processing. TDLAS and QEPAS can achieve minimum detectable absorption losses in the range from 10-8 to 10-11cm-1/Hz1/2. Several recent examples of real world applications of field deployable gas sensors will be described. For example, an ICL based TDLAS sensor system is capable of detecting CH4 and C2H6 concentration levels of 1 ppb in a 1 sec. sampling time, using an ultra-compact, robust sensor architecture. H2S detection was realized with a THz QEPAS sensor

  11. Path to Impact for Autonomous Field Deployable Chemical Sensors: A Case Study of in Situ Nitrite Sensors.

    Science.gov (United States)

    Schierenbeck, Tim M; Smith, Matthew C

    2017-05-02

    Natural freshwater systems have been severely affected by excess loading of macronutrients (e.g., nitrogen and phosphorus) from fertilizers, fossil fuels, and human and livestock waste. In the USA, impacts to drinking water quality, biogeochemical cycles, and aquatic ecosystems are estimated to cost US$210 billion annually. Field-deployable nutrient sensors (FDS) offer potential to support research and resource management efforts by acquiring higher resolution data than are currently supported by expensive conventional sampling methods. Following nearly 40 years of research and development, FDS instruments are now starting to penetrate commercial markets. However, instrument uncertainty factors (high cost, reliability, accuracy, and precision) are key drivers impeding the uptake of FDS by the majority of users. Using nitrite sensors as a case study, we review the trends, opportunities, and challenges in producing and implementing FDS from a perspective of innovation and impact. We characterize the user community and consumer needs, identify trends in research approaches, tabulate state-of-the-art examples and specifications, and discuss data life cycle considerations. With further development of FDS through prototyping and testing in real-world applications, these tools can deliver information for protecting and restoring natural waters, enhancing process control for industrial operations and water treatment, and providing novel research insights.

  12. Markovian agents models for wireless sensor networks deployed in environmental protection

    International Nuclear Information System (INIS)

    Cerotti, Davide; Gribaudo, Marco; Bobbio, Andrea

    2014-01-01

    Wireless sensor networks (WSNs) are gaining popularity as distributed monitoring systems in safety critical applications, when the location to be controlled may be dangerous for a human operator or difficult to access. Fire is one of the major thread in urban as well as in open environments, and WSNs are receiving increasing attention as a mean to build effective and timely fire protection systems. The present paper presents a novel analytical technique for the study of the propagation of a fire in a wide open area and the interaction with a WSN deployed to monitor the outbreak of the fire and to send a warning signal to a base station. For the complex scenario under study, an analytical modeling and analysis technique based on Markovian agents (MAs) is discussed. It is shown that, even if the overall state space of the models is huge, nevertheless an analytical solution is feasible, by exploiting the locality of the interactions among MAs, based on a message passing mechanism combined with a perception function. - Highlights: • We present a revised theory of Markovian agent models, detailing the analysis techniques and its complexity • We a target a complex application of a wireless sensor network (WSN) that monitors forest fire. • The model captures the propagation of fire, heat, and the detection by the WSN. • We compute key performance indices such us the fire propagation front, and message travel time. • We perform an extensive set of experiments to study the effectiveness of the WSN in detecting forest fire

  13. Enhanced Deployment Strategy for Role-Based Hierarchical Application Agents in Wireless Sensor Networks with Established Clusterheads

    Science.gov (United States)

    Gendreau, Audrey

    2014-01-01

    Efficient self-organizing virtual clusterheads that supervise data collection based on their wireless connectivity, risk, and overhead costs, are an important element of Wireless Sensor Networks (WSNs). This function is especially critical during deployment when system resources are allocated to a subsequent application. In the presented research,…

  14. MOFs for the Sensitive Detection of Ammonia: Deployment of fcu-MOF Thin-Films as Effective Chemical Capacitive Sensors.

    KAUST Repository

    Assen, Ayalew Hussen Assen; Yassine, Omar; Shekhah, Osama; Eddaoudi, Mohamed; Salama, Khaled N.

    2017-01-01

    This work reports on the fabrication and deployment of a select metal-organic framework (MOF) thin film as an advanced chemical capacitive sensor for the sensing/detection of ammonia (NH3) at room temperature. Namely, the MOF thin film sensing layer

  15. Distributed clone detection in static wireless sensor networks: random walk with network division.

    Science.gov (United States)

    Khan, Wazir Zada; Aalsalem, Mohammed Y; Saad, N M

    2015-01-01

    Wireless Sensor Networks (WSNs) are vulnerable to clone attacks or node replication attacks as they are deployed in hostile and unattended environments where they are deprived of physical protection, lacking physical tamper-resistance of sensor nodes. As a result, an adversary can easily capture and compromise sensor nodes and after replicating them, he inserts arbitrary number of clones/replicas into the network. If these clones are not efficiently detected, an adversary can be further capable to mount a wide variety of internal attacks which can emasculate the various protocols and sensor applications. Several solutions have been proposed in the literature to address the crucial problem of clone detection, which are not satisfactory as they suffer from some serious drawbacks. In this paper we propose a novel distributed solution called Random Walk with Network Division (RWND) for the detection of node replication attack in static WSNs which is based on claimer-reporter-witness framework and combines a simple random walk with network division. RWND detects clone(s) by following a claimer-reporter-witness framework and a random walk is employed within each area for the selection of witness nodes. Splitting the network into levels and areas makes clone detection more efficient and the high security of witness nodes is ensured with moderate communication and memory overheads. Our simulation results show that RWND outperforms the existing witness node based strategies with moderate communication and memory overheads.

  16. Distributed clone detection in static wireless sensor networks: random walk with network division.

    Directory of Open Access Journals (Sweden)

    Wazir Zada Khan

    Full Text Available Wireless Sensor Networks (WSNs are vulnerable to clone attacks or node replication attacks as they are deployed in hostile and unattended environments where they are deprived of physical protection, lacking physical tamper-resistance of sensor nodes. As a result, an adversary can easily capture and compromise sensor nodes and after replicating them, he inserts arbitrary number of clones/replicas into the network. If these clones are not efficiently detected, an adversary can be further capable to mount a wide variety of internal attacks which can emasculate the various protocols and sensor applications. Several solutions have been proposed in the literature to address the crucial problem of clone detection, which are not satisfactory as they suffer from some serious drawbacks. In this paper we propose a novel distributed solution called Random Walk with Network Division (RWND for the detection of node replication attack in static WSNs which is based on claimer-reporter-witness framework and combines a simple random walk with network division. RWND detects clone(s by following a claimer-reporter-witness framework and a random walk is employed within each area for the selection of witness nodes. Splitting the network into levels and areas makes clone detection more efficient and the high security of witness nodes is ensured with moderate communication and memory overheads. Our simulation results show that RWND outperforms the existing witness node based strategies with moderate communication and memory overheads.

  17. Industrial Wireless Sensors: A User's Perspective on the Impact of Standards on Wide-spread Deployment

    Energy Technology Data Exchange (ETDEWEB)

    Taft, Cyrus W. [Taft Engineering, Inc.; Manges, Wayne W [ORNL; Sorge, John N [Southern Company Services, Inc.

    2012-01-01

    The role of wireless sensing technologies in industrial instrumentation will undoubtedly become more important in the years ahead. . Deployment of such instrumentation in an industrial setting with its heightened security and robustness criteria hinges on user acceptance of verified performance as well as meeting cost requirements. Today, industrial users face many choices when specifying a wireless sensor network, including radio performance, battery life, interoperability, security, and standards compliance. The potential market for industrial wireless sensors is literally millions of wireless instruments and it is imperative that accurate information for applying the technology to real-world applications be available to the end-user so that they can make informed deployment decisions. The majority of industrial wireless automation designs now being deployed or being considered for deployment are based on three different standards . The HART Communications Foundation s WirelessHART (IEC 62591), the International Society of Automation s ISA100.11a, and the offering from the Industrial Wireless Alliance of China known as WIA-PA (IEC 62601). Aside from these industrial automation standards, users must also be cognizant of the underlying wireless network standards IEEE 802.11, IEEE 802.15.4, and IEEE 802.15.3a and their interactions with the three principal industrial automation protocols mentioned previously. The crucial questions being asked by end users revolve around sensor network performance, interoperability, reliability, and security. This paper will discuss potential wireless sensor applications in power plants, barriers to the acceptance of wireless technology, concerns related to standards, and provide an end user prospective on the issues affecting wide-spread deployment of wireless sensors. Finally, the authors conclude with a discussion of a recommended path forward including how standards organizations can better facilitate end user decision making and

  18. A randomized multicenter trial of minimally invasive rapid deployment versus conventional full sternotomy aortic valve replacement.

    Science.gov (United States)

    Borger, Michael A; Moustafine, Vadim; Conradi, Lenard; Knosalla, Christoph; Richter, Markus; Merk, Denis R; Doenst, Torsten; Hammerschmidt, Robert; Treede, Hendrik; Dohmen, Pascal; Strauch, Justus T

    2015-01-01

    Minimally invasive surgical procedures (MIS) may offer several advantages over conventional full sternotomy (FS) aortic valve replacement (AVR). A novel class of aortic valve prostheses has been developed for rapid-deployment AVR (RDAVR). We report a randomized, multicenter trial comparing the outcomes for MIS-RDAVR with those of conventional FS-AVR. A total of 100 patients with aortic stenosis were enrolled in a prospective, multicenter, randomized comparison trial (CADENCE-MIS). Exclusion criteria included ejection fraction below 25%, AVR requiring concomitant procedures, and recent myocardial infarction or stroke. Patients were randomized to undergo MIS-RDAVR through an upper hemisternotomy (n = 51) or AVR by FS with a conventional stented bioprosthesis (n = 49). Three patients were excluded before the procedure, and 3 more patients who were randomized to undergo RDAVR were excluded because of their anatomy. Procedural, early clinical outcomes, and functional outcomes were assessed for the remaining 94 patients. Hemodynamic performance was assessed by an echocardiography core laboratory. Implanted valve sizes were similar between groups (22.9 ± 2.1 vs 23.0 ± 2.1 mm, p = 0.9). MIS-RDAVR was associated with significantly reduced aortic cross-clamp times compared with FS-AVR (41.3 ± 20.3 vs 54.0 ± 20.3 minutes, p quality of life measures. The RDAVR patients had a significantly lower mean transvalvular gradient (8.5 vs 10.3 mm Hg, p = 0.044) and a lower prevalence of patient-prosthesis mismatch (0% vs 15.0%, p = 0.013) 3 months postoperatively compared with the FS-AVR patients. RDAVR by the MIS approach is associated with significantly reduced myocardial ischemic time and better valvular hemodynamic function than FS-AVR with a conventional stented bioprosthesis. Rapid deployment valves may facilitate the performance of MIS-AVR. Copyright © 2015 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

  19. Correlation Processing Of Local Seismic Data: Applications for Autonomous Sensor Deployments

    Energy Technology Data Exchange (ETDEWEB)

    Dodge, D A

    2010-11-16

    Excavation and operation of an underground facility is likely to produce an extensive suite of seismic signals observable at the surface for perhaps several km. Probably a large fraction of such signals will be correlated, so the design of a monitoring framework should include consideration of a correlation processing capability. Correlation detectors have been shown to be significantly more sensitive than beam-forming power detectors. Although correlation detectors have a limited detection footprint, they can be generalized into multi-rank subspace detectors which are sensitive over a much larger range of source mechanisms and positions. Production of subspace detectors can be automated, so their use in an autonomous framework may be contemplated. Waveform correlation also can be used to produce very high precision phase picks which may be jointly inverted to simultaneously relocate groups of events. The relative precision of the resulting hypocenters is sufficient to visualize structural detail at a scale of less than a few tens of meters. Three possible correlation processor systems are presented. All use a subspace signal detection framework. The simplest system uses a single-component sensor and is capable of detection and classification of signals. The most complicated system uses many sensors deployed around the facility, and is capable of detection, classification, and high-precision source location. Data from a deep underground mine are presented to demonstrate the applicability of correlation processing to monitoring an underground facility. Although the source region covers an area of about 600m by 580m, all but two of the events form clusters at a threshold of 0.7. All the events could have been detected and classified by the subspace detection framework, and high-precision picks can be computed for all cluster members.

  20. The deployment of carbon monoxide wireless sensor network (CO-WSN) for ambient air monitoring.

    Science.gov (United States)

    Chaiwatpongsakorn, Chaichana; Lu, Mingming; Keener, Tim C; Khang, Soon-Jai

    2014-06-16

    Wireless sensor networks are becoming increasingly important as an alternative solution for environment monitoring because they can reduce cost and complexity. Also, they can improve reliability and data availability in places where traditional monitoring methods are difficult to site. In this study, a carbon monoxide wireless sensor network (CO-WSN) was developed to measure carbon monoxide concentrations at a major traffic intersection near the University of Cincinnati main campus. The system has been deployed over two weeks during Fall 2010, and Summer 2011-2012, traffic data was also recorded by using a manual traffic counter and a video camcorder to characterize vehicles at the intersection 24 h, particularly, during the morning and evening peak hour periods. According to the field test results, the 1 hr-average CO concentrations were found to range from 0.1-1.0 ppm which is lower than the National Ambient Air Quality Standards (NAAQS) 35 ppm on a one-hour averaging period. During rush hour periods, the traffic volume at the intersection varied from 2,067 to 3,076 vehicles per hour with 97% being passenger vehicles. Furthermore, the traffic volume based on a 1-h average showed good correlation (R2 = 0.87) with the 1-h average CO-WSN concentrations for morning and evening peak time periods whereas CO-WSN results provided a moderate correlation (R2 = 0.42) with 24 hours traffic volume due to fluctuated changes of meteorological conditions. It is concluded that the performance and the reliability of wireless ambient air monitoring networks can be used as an alternative method for real time air monitoring.

  1. Pervasive surveillance-agent system based on wireless sensor networks: design and deployment

    International Nuclear Information System (INIS)

    Martínez, José F; Bravo, Sury; García, Ana B; Corredor, Iván; Familiar, Miguel S; López, Lourdes; Hernández, Vicente; Da Silva, Antonio

    2010-01-01

    Nowadays, proliferation of embedded systems is enhancing the possibilities of gathering information by using wireless sensor networks (WSNs). Flexibility and ease of installation make these kinds of pervasive networks suitable for security and surveillance environments. Moreover, the risk for humans to be exposed to these functions is minimized when using these networks. In this paper, a virtual perimeter surveillance agent, which has been designed to detect any person crossing an invisible barrier around a marked perimeter and send an alarm notification to the security staff, is presented. This agent works in a state of 'low power consumption' until there is a crossing on the perimeter. In our approach, the 'intelligence' of the agent has been distributed by using mobile nodes in order to discern the cause of the event of presence. This feature contributes to saving both processing resources and power consumption since the required code that detects presence is the only system installed. The research work described in this paper illustrates our experience in the development of a surveillance system using WNSs for a practical application as well as its evaluation in real-world deployments. This mechanism plays an important role in providing confidence in ensuring safety to our environment

  2. Analysis of wireless sensor network topology and estimation of optimal network deployment by deterministic radio channel characterization.

    Science.gov (United States)

    Aguirre, Erik; Lopez-Iturri, Peio; Azpilicueta, Leire; Astrain, José Javier; Villadangos, Jesús; Falcone, Francisco

    2015-02-05

    One of the main challenges in the implementation and design of context-aware scenarios is the adequate deployment strategy for Wireless Sensor Networks (WSNs), mainly due to the strong dependence of the radiofrequency physical layer with the surrounding media, which can lead to non-optimal network designs. In this work, radioplanning analysis for WSN deployment is proposed by employing a deterministic 3D ray launching technique in order to provide insight into complex wireless channel behavior in context-aware indoor scenarios. The proposed radioplanning procedure is validated with a testbed implemented with a Mobile Ad Hoc Network WSN following a chain configuration, enabling the analysis and assessment of a rich variety of parameters, such as received signal level, signal quality and estimation of power consumption. The adoption of deterministic radio channel techniques allows the design and further deployment of WSNs in heterogeneous wireless scenarios with optimized behavior in terms of coverage, capacity, quality of service and energy consumption.

  3. How well could existing sensors detect the deployment of a solar radiation management (SRM) geoengineering effort?

    Energy Technology Data Exchange (ETDEWEB)

    Hurd, Alan J. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2016-04-29

    While the stated reason for asking this question is “to understand better our ability to warn policy makers in the unlikely event of an unanticipated SRM geoengineering deployment or large-scale field experiment”, my colleagues and I felt that motives would be important context because the scale of any meaningful SRM deployment would be so large that covert deployment seems impossible. However, several motives emerged that suggest a less-than-global effort might be important.

  4. Method for Optimal Sensor Deployment on 3D Terrains Utilizing a Steady State Genetic Algorithm with a Guided Walk Mutation Operator Based on the Wavelet Transform

    Science.gov (United States)

    Unaldi, Numan; Temel, Samil; Asari, Vijayan K.

    2012-01-01

    One of the most critical issues of Wireless Sensor Networks (WSNs) is the deployment of a limited number of sensors in order to achieve maximum coverage on a terrain. The optimal sensor deployment which enables one to minimize the consumed energy, communication time and manpower for the maintenance of the network has attracted interest with the increased number of studies conducted on the subject in the last decade. Most of the studies in the literature today are proposed for two dimensional (2D) surfaces; however, real world sensor deployments often arise on three dimensional (3D) environments. In this paper, a guided wavelet transform (WT) based deployment strategy (WTDS) for 3D terrains, in which the sensor movements are carried out within the mutation phase of the genetic algorithms (GAs) is proposed. The proposed algorithm aims to maximize the Quality of Coverage (QoC) of a WSN via deploying a limited number of sensors on a 3D surface by utilizing a probabilistic sensing model and the Bresenham's line of sight (LOS) algorithm. In addition, the method followed in this paper is novel to the literature and the performance of the proposed algorithm is compared with the Delaunay Triangulation (DT) method as well as a standard genetic algorithm based method and the results reveal that the proposed method is a more powerful and more successful method for sensor deployment on 3D terrains. PMID:22666078

  5. A Novel Solid State Non-Dispersive Infrared CO2 Gas Sensor Compatible with Wireless and Portable Deployment

    Directory of Open Access Journals (Sweden)

    Desmond Gibson

    2013-05-01

    Full Text Available This paper describes development of a novel mid-infrared light emitting diode (LED and photodiode (PD light source/detector combination and use within a non-dispersive infrared (NDIR carbon dioxide gas sensor. The LED/PD based NDIR sensor provides fast stabilisation time (time required to turn on the sensor from cold, warm up, take and report a measurement, and power down again ≈1 second, longevity (>15 years, low power consumption and low cost. Described performance is compatible with “fit and forget” wireless deployed sensors in applications such as indoor air quality monitoring/control & energy conservation in buildings, transport systems, horticultural greenhouses and portable deployment for safety, industrial and medical applications. Fast stabilisation time, low intrinsic power consumption and cycled operation offer typical energy consumption per measurement of mJ’s, providing extended operation using battery and/or energy harvesting strategies (measurement interval of ≈ 2 minutes provides >10 years operation from one AA battery. Specific performance data is provided in relation to measurement accuracy and noise, temperature performance, cross sensitivity, measurement range (two pathlength variants are described covering ambient through to 100% gas concentration, comparison with NDIR utilizing thermal source/pyroelectric light source/detector combination and compatibility with energy harvesting. Semiconductor based LED/PD processing together with injection moulded reflective optics and simple assembly provide a route to low cost high volume manufacturing.

  6. A novel solid state non-dispersive infrared CO2 gas sensor compatible with wireless and portable deployment.

    Science.gov (United States)

    Gibson, Desmond; MacGregor, Calum

    2013-05-29

    This paper describes development of a novel mid-infrared light emitting diode (LED) and photodiode (PD) light source/detector combination and use within a non-dispersive infrared (NDIR) carbon dioxide gas sensor. The LED/PD based NDIR sensor provides fast stabilisation time (time required to turn on the sensor from cold, warm up, take and report a measurement, and power down again ≈1 second), longevity (>15 years), low power consumption and low cost. Described performance is compatible with "fit and forget" wireless deployed sensors in applications such as indoor air quality monitoring/control & energy conservation in buildings, transport systems, horticultural greenhouses and portable deployment for safety, industrial and medical applications. Fast stabilisation time, low intrinsic power consumption and cycled operation offer typical energy consumption per measurement of mJ's, providing extended operation using battery and/or energy harvesting strategies (measurement interval of ≈ 2 minutes provides >10 years operation from one AA battery). Specific performance data is provided in relation to measurement accuracy and noise, temperature performance, cross sensitivity, measurement range (two pathlength variants are described covering ambient through to 100% gas concentration), comparison with NDIR utilizing thermal source/pyroelectric light source/detector combination and compatibility with energy harvesting. Semiconductor based LED/PD processing together with injection moulded reflective optics and simple assembly provide a route to low cost high volume manufacturing.

  7. The Global Seismographic Network (GSN): Deployment of Next Generation VBB Borehole Sensors and Improving Overall Network Noise Performance

    Science.gov (United States)

    Hafner, K.; Davis, P.; Wilson, D.; Sumy, D.

    2017-12-01

    The Global Seismographic Network (GSN) recently received delivery of the next generation Very Broadband (VBB) borehole sensors purchased through funding from the DOE. Deployment of these sensors will be underway during the end of summer and fall of 2017 and they will eventually replace the aging KS54000 sensors at approximately one-third of the GSN network stations. We will present the latest methods of deploying these sensors in the existing deep boreholes. To achieve lower noise performance at some sites, emplacement in shallow boreholes might result in lower noise performance for the existing site conditions. In some cases shallow borehole installations may be adapted to vault stations (which make up two thirds of the network), as a means of reducing tilt-induced signals on the horizontal components. The GSN is creating a prioritized list of equipment upgrades at selected stations with the ultimate goal of optimizing overall network data availability and noise performance. For an overview of the performance of the current GSN relative to selected set of metrics, we are utilizing data quality metrics and Probability Density Functions (PDFs)) generated by the IRIS Data Management Centers' (DMC) MUSTANG (Modular Utility for Statistical Knowledge Gathering) and LASSO (Latest Assessment of Seismic Station Observations) tools. We will present our metric analysis of GSN performance in 2016, and show the improvements at GSN sites resulting from recent instrumentation and infrastructure upgrades.

  8. Design and Analysis of Cost-Efficient Sensor Deployment for Tracking Small UAS with Agent-Based Modeling.

    Science.gov (United States)

    Shin, Sangmi; Park, Seongha; Kim, Yongho; Matson, Eric T

    2016-04-22

    Recently, commercial unmanned aerial systems (UAS) have gained popularity. However, these UAS are potential threats to people in terms of safety in public places, such as public parks or stadiums. To reduce such threats, we consider a design, modeling, and evaluation of a cost-efficient sensor system that detects and tracks small UAS. In this research, we focus on discovering the best sensor deployments by simulating different types and numbers of sensors in a designated area, which provide reasonable detection rates at low costs. Also, the system should cover the crowded areas more thoroughly than vacant areas to reduce direct threats to people underneath. This research study utilized the Agent-Based Modeling (ABM) technique to model a system consisting of independent and heterogeneous agents that interact with each other. Our previous work presented the ability to apply ABM to analyze the sensor configurations with two types of radars in terms of cost-efficiency. The results from the ABM simulation provide a list of candidate configurations and deployments that can be referred to for applications in the real world environment.

  9. Design and Analysis of Cost-Efficient Sensor Deployment for Tracking Small UAS with Agent-Based Modeling

    Directory of Open Access Journals (Sweden)

    Sangmi Shin

    2016-04-01

    Full Text Available Recently, commercial unmanned aerial systems (UAS have gained popularity. However, these UAS are potential threats to people in terms of safety in public places, such as public parks or stadiums. To reduce such threats, we consider a design, modeling, and evaluation of a cost-efficient sensor system that detects and tracks small UAS. In this research, we focus on discovering the best sensor deployments by simulating different types and numbers of sensors in a designated area, which provide reasonable detection rates at low costs. Also, the system should cover the crowded areas more thoroughly than vacant areas to reduce direct threats to people underneath. This research study utilized the Agent-Based Modeling (ABM technique to model a system consisting of independent and heterogeneous agents that interact with each other. Our previous work presented the ability to apply ABM to analyze the sensor configurations with two types of radars in terms of cost-efficiency. The results from the ABM simulation provide a list of candidate configurations and deployments that can be referred to for applications in the real world environment.

  10. Enhanced Deployment Strategy for Role-based Hierarchical Application Agents in Wireless Sensor Networks with Established Clusterheads

    Science.gov (United States)

    Gendreau, Audrey

    Efficient self-organizing virtual clusterheads that supervise data collection based on their wireless connectivity, risk, and overhead costs, are an important element of Wireless Sensor Networks (WSNs). This function is especially critical during deployment when system resources are allocated to a subsequent application. In the presented research, a model used to deploy intrusion detection capability on a Local Area Network (LAN), in the literature, was extended to develop a role-based hierarchical agent deployment algorithm for a WSN. The resulting model took into consideration the monitoring capability, risk, deployment distribution cost, and monitoring cost associated with each node. Changing the original LAN methodology approach to model a cluster-based sensor network depended on the ability to duplicate a specific parameter that represented the monitoring capability. Furthermore, other parameters derived from a LAN can elevate costs and risk of deployment, as well as jeopardize the success of an application on a WSN. A key component of the approach presented in this research was to reduce the costs when established clusterheads in the network were found to be capable of hosting additional detection agents. In addition, another cost savings component of the study addressed the reduction of vulnerabilities associated with deployment of agents to high volume nodes. The effectiveness of the presented method was validated by comparing it against a type of a power-based scheme that used each node's remaining energy as the deployment value. While available energy is directly related to the model used in the presented method, the study deliberately sought out nodes that were identified with having superior monitoring capability, cost less to create and sustain, and are at low-risk of an attack. This work investigated improving the efficiency of an intrusion detection system (IDS) by using the proposed model to deploy monitoring agents after a temperature sensing

  11. Evaluation of the Impact of Furniture on Communications Performance for Ubiquitous Deployment of Wireless Sensor Networks in Smart Homes

    Science.gov (United States)

    Bleda, Andrés L.; Jara, Antonio J.; Maestre, Rafael; Santa, Guadalupe; Gómez Skarmeta, Antonio F.

    2012-01-01

    The extensions of the environment with the integration of sensing systems in any space, in conjunction with ubiquitous computing are enabling the so-called Smart Space Sensor Networks. This new generation of networks are offering full connectivity with any object, through the Internet of Things (IoT) and/or the Web, i.e., the Web of Things. These connectivity capabilities are making it feasible to sense the behaviours of people at home and act accordingly. These sensing systems must be integrated within typical elements found at home such as furniture. For that reason, this work considers furniture as an interesting element for the transparent location of sensors. Furniture is a ubiquitous object, i.e., it can be found everywhere at home or the office, and it can integrate and hide the sensors of a network. This work addresses the lack of an exhaustive study of the effect of furniture on signal losses. In addition an easy-to-use tool for estimating the robustness of the communication channel among the sensor nodes and gateways is proposed. Specifically, the losses in a sensor network signal due to the materials found within the communication link are evaluated. Then, this work proposes a software tool that gathers the obtained results and is capable of evaluating the impact of a given set of materials on the communications. This tool also provides a mechanism to optimize the sensor network deployments during the definition of smart spaces. Specifically, it provides information such as: maximum distances between sensor nodes, most suitable type of furniture to integrate sensors, or battery life of sensor nodes. This tool has been validated empirically in the lab, and it is currently being used by several enterprise partners of the Technological Centre of Furniture and Wood in the southeast of Spain. PMID:22778653

  12. Evaluation of the impact of furniture on communications performance for ubiquitous deployment of Wireless Sensor Networks in smart homes.

    Science.gov (United States)

    Bleda, Andrés L; Jara, Antonio J; Maestre, Rafael; Santa, Guadalupe; Gómez Skarmeta, Antonio F

    2012-01-01

    The extensions of the environment with the integration of sensing systems in any space, in conjunction with ubiquitous computing are enabling the so-called Smart Space Sensor Networks. This new generation of networks are offering full connectivity with any object, through the Internet of Things (IoT) and/or the Web, i.e., the Web of Things. These connectivity capabilities are making it feasible to sense the behaviours of people at home and act accordingly. These sensing systems must be integrated within typical elements found at home such as furniture. For that reason, this work considers furniture as an interesting element for the transparent location of sensors. Furniture is a ubiquitous object, i.e., it can be found everywhere at home or the office, and it can integrate and hide the sensors of a network. This work addresses the lack of an exhaustive study of the effect of furniture on signal losses. In addition an easy-to-use tool for estimating the robustness of the communication channel among the sensor nodes and gateways is proposed. Specifically, the losses in a sensor network signal due to the materials found within the communication link are evaluated. Then, this work proposes a software tool that gathers the obtained results and is capable of evaluating the impact of a given set of materials on the communications. This tool also provides a mechanism to optimize the sensor network deployments during the definition of smart spaces. Specifically, it provides information such as: maximum distances between sensor nodes, most suitable type of furniture to integrate sensors, or battery life of sensor nodes. This tool has been validated empirically in the lab, and it is currently being used by several enterprise partners of the Technological Centre of Furniture and Wood in the southeast of Spain.

  13. Evaluation of the Impact of Furniture on Communications Performance for Ubiquitous Deployment of Wireless Sensor Networks in Smart Homes

    Directory of Open Access Journals (Sweden)

    Antonio F. Gómez Skarmeta

    2012-05-01

    Full Text Available The extensions of the environment with the integration of sensing systems in any space, in conjunction with ubiquitous computing are enabling the so-called Smart Space Sensor Networks. This new generation of networks are offering full connectivity with any object, through the Internet of Things (IoT and/or the Web, i.e., the Web of Things. These connectivity capabilities are making it feasible to sense the behaviours of people at home and act accordingly. These sensing systems must be integrated within typical elements found at home such as furniture. For that reason, this work considers furniture as an interesting element for the transparent location of sensors. Furniture is a ubiquitous object, i.e., it can be found everywhere at home or the office, and it can integrate and hide the sensors of a network. This work addresses the lack of an exhaustive study of the effect of furniture on signal losses. In addition an easy-to-use tool for estimating the robustness of the communication channel among the sensor nodes and gateways is proposed. Specifically, the losses in a sensor network signal due to the materials found within the communication link are evaluated. Then, this work proposes a software tool that gathers the obtained results and is capable of evaluating the impact of a given set of materials on the communications. This tool also provides a mechanism to optimize the sensor network deployments during the definition of smart spaces. Specifically, it provides information such as: maximum distances between sensor nodes, most suitable type of furniture to integrate sensors, or battery life of sensor nodes. This tool has been validated empirically in the lab, and it is currently being used by several enterprise partners of the Technological Centre of Furniture and Wood in the southeast of Spain.

  14. An Energy-Efficient Secure Routing and Key Management Scheme for Mobile Sinks in Wireless Sensor Networks Using Deployment Knowledge

    Directory of Open Access Journals (Sweden)

    Le Xuan Hung

    2008-12-01

    Full Text Available For many sensor network applications such as military or homeland security, it is essential for users (sinks to access the sensor network while they are moving. Sink mobility brings new challenges to secure routing in large-scale sensor networks. Previous studies on sink mobility have mainly focused on efficiency and effectiveness of data dissemination without security consideration. Also, studies and experiences have shown that considering security during design time is the best way to provide security for sensor network routing. This paper presents an energy-efficient secure routing and key management for mobile sinks in sensor networks, called SCODEplus. It is a significant extension of our previous study in five aspects: (1 Key management scheme and routing protocol are considered during design time to increase security and efficiency; (2 The network topology is organized in a hexagonal plane which supports more efficiency than previous square-grid topology; (3 The key management scheme can eliminate the impacts of node compromise attacks on links between non-compromised nodes; (4 Sensor node deployment is based on Gaussian distribution which is more realistic than uniform distribution; (5 No GPS or like is required to provide sensor node location information. Our security analysis demonstrates that the proposed scheme can defend against common attacks in sensor networks including node compromise attacks, replay attacks, selective forwarding attacks, sinkhole and wormhole, Sybil attacks, HELLO flood attacks. Both mathematical and simulation-based performance evaluation show that the SCODEplus significantly reduces the communication overhead, energy consumption, packet delivery latency while it always delivers more than 97 percent of packets successfully.

  15. A Social Potential Fields Approach for Self-Deployment and Self-Healing in Hierarchical Mobile Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Eva González-Parada

    2017-01-01

    Full Text Available Autonomous mobile nodes in mobile wireless sensor networks (MWSN allow self-deployment and self-healing. In both cases, the goals are: (i to achieve adequate coverage; and (ii to extend network life. In dynamic environments, nodes may use reactive algorithms so that each node locally decides when and where to move. This paper presents a behavior-based deployment and self-healing algorithm based on the social potential fields algorithm. In the proposed algorithm, nodes are attached to low cost robots to autonomously navigate in the coverage area. The proposed algorithm has been tested in environments with and without obstacles. Our study also analyzes the differences between non-hierarchical and hierarchical routing configurations in terms of network life and coverage.

  16. A Social Potential Fields Approach for Self-Deployment and Self-Healing in Hierarchical Mobile Wireless Sensor Networks.

    Science.gov (United States)

    González-Parada, Eva; Cano-García, Jose; Aguilera, Francisco; Sandoval, Francisco; Urdiales, Cristina

    2017-01-09

    Autonomous mobile nodes in mobile wireless sensor networks (MWSN) allow self-deployment and self-healing. In both cases, the goals are: (i) to achieve adequate coverage; and (ii) to extend network life. In dynamic environments, nodes may use reactive algorithms so that each node locally decides when and where to move. This paper presents a behavior-based deployment and self-healing algorithm based on the social potential fields algorithm. In the proposed algorithm, nodes are attached to low cost robots to autonomously navigate in the coverage area. The proposed algorithm has been tested in environments with and without obstacles. Our study also analyzes the differences between non-hierarchical and hierarchical routing configurations in terms of network life and coverage.

  17. Deployment Design of Wireless Sensor Network for Simple Multi-Point Surveillance of a Moving Target

    Science.gov (United States)

    Tsukamoto, Kazuya; Ueda, Hirofumi; Tamura, Hitomi; Kawahara, Kenji; Oie, Yuji

    2009-01-01

    In this paper, we focus on the problem of tracking a moving target in a wireless sensor network (WSN), in which the capability of each sensor is relatively limited, to construct large-scale WSNs at a reasonable cost. We first propose two simple multi-point surveillance schemes for a moving target in a WSN and demonstrate that one of the schemes can achieve high tracking probability with low power consumption. In addition, we examine the relationship between tracking probability and sensor density through simulations, and then derive an approximate expression representing the relationship. As the results, we present guidelines for sensor density, tracking probability, and the number of monitoring sensors that satisfy a variety of application demands. PMID:22412326

  18. Three dimensional multi perspective imaging with randomly distributed sensors

    International Nuclear Information System (INIS)

    DaneshPanah, Mehdi; Javidi, Bahrain

    2008-01-01

    In this paper, we review a three dimensional (3D) passive imaging system that exploits the visual information captured from the scene from multiple perspectives to reconstruct the scene voxel by voxel in 3D space. The primary contribution of this work is to provide a computational reconstruction scheme based on randomly distributed sensor locations in space. In virtually all of multi perspective techniques (e.g. integral imaging, synthetic aperture integral imaging, etc), there is an implicit assumption that the sensors lie on a simple, regular pickup grid. Here, we relax this assumption and suggest a computational reconstruction framework that unifies the available methods as its special cases. The importance of this work is that it enables three dimensional imaging technology to be implemented in a multitude of novel application domains such as 3D aerial imaging, collaborative imaging, long range 3D imaging and etc, where sustaining a regular pickup grid is not possible and/or the parallax requirements call for a irregular or sparse synthetic aperture mode. Although the sensors can be distributed in any random arrangement, we assume that the pickup position is measured at the time of capture of each elemental image. We demonstrate the feasibility of the methods proposed here by experimental results.

  19. MOFs for the Sensitive Detection of Ammonia: Deployment of fcu-MOF Thin Films as Effective Chemical Capacitive Sensors.

    Science.gov (United States)

    Assen, Ayalew H; Yassine, Omar; Shekhah, Osama; Eddaoudi, Mohamed; Salama, Khaled N

    2017-09-22

    This work reports on the fabrication and deployment of a select metal-organic framework (MOF) thin film as an advanced chemical capacitive sensor for the sensing/detection of ammonia (NH 3 ) at room temperature. Namely, the MOF thin film sensing layer consists of a rare-earth (RE) MOF (RE-fcu-MOF) deposited on a capacitive interdigitated electrode (IDE). Purposely, the chemically stable naphthalene-based RE-fcu-MOF (NDC-Y-fcu-MOF) was elected and prepared/arranged as a thin film on a prefunctionalized capacitive IDE via the solvothermal growth method. Unlike earlier realizations, the fabricated MOF-based sensor showed a notable detection sensitivity for NH 3 at concentrations down to 1 ppm, with a detection limit appraised to be around 100 ppb (at room temperature) even in the presence of humidity and/or CO 2 . Distinctly, the NDC-Y-fcu-MOF based sensor exhibited the required stability to NH 3 , in contrast to other reported MOFs, and a remarkable detection selectivity toward NH 3 vs CH 4 , NO 2 , H 2 , and C 7 H 8 . The NDC-Y-fcu-MOF based sensor exhibited excellent performance for sensing ammonia for simulated breathing system in the presence of the mixture of carbon dioxide and/or humidity (water vapor), with no major alteration in the detection signal.

  20. MOFs for the Sensitive Detection of Ammonia: Deployment of fcu-MOF Thin-Films as Effective Chemical Capacitive Sensors.

    KAUST Repository

    Assen, Ayalew Hussen Assen

    2017-08-15

    This work reports on the fabrication and deployment of a select metal-organic framework (MOF) thin film as an advanced chemical capacitive sensor for the sensing/detection of ammonia (NH3) at room temperature. Namely, the MOF thin film sensing layer consists of a rare-earth (RE) MOF (RE-fcu-MOF) deposited on a capacitive interdigitated electrode (IDE). Purposely, the chemically stable naphthalene-based RE-fcu-MOF (NDC-Y-fcu-MOF) was elected and prepared/arranged as a thin film on a pre-functionalized capacitive IDE via the solvothermal growth method. Unlike earlier realizations, the fabricated MOF-based sensor showed a notable detection sensitivity for NH3 at concentrations down to 1 ppm, with a detection limit appraised to be around 100 ppb (at room temperature) even in the presence of humidity and/or CO2. Distinctly, the NDC-Y-fcu-MOF based sensor exhibited the required stability to NH3, in contract to other reported MOFs, and a remarkable detection selectivity towards NH3 vs. CH4, NO2, H2 and C7H8. The NDC-Y-fcu-MOF based sensor exhibited excellent performance for sensing ammonia for simulated breathing system in the presence of the mixture of carbon dioxide and/or humidity (water vapor), with no major alteration in the detection signal.

  1. Localization-Free Detection of Replica Node Attacks in Wireless Sensor Networks Using Similarity Estimation with Group Deployment Knowledge

    Directory of Open Access Journals (Sweden)

    Chao Ding

    2017-01-01

    Full Text Available Due to the unattended nature and poor security guarantee of the wireless sensor networks (WSNs, adversaries can easily make replicas of compromised nodes, and place them throughout the network to launch various types of attacks. Such an attack is dangerous because it enables the adversaries to control large numbers of nodes and extend the damage of attacks to most of the network with quite limited cost. To stop the node replica attack, we propose a location similarity-based detection scheme using deployment knowledge. Compared with prior solutions, our scheme provides extra functionalities that prevent replicas from generating false location claims without deploying resource-consuming localization techniques on the resource-constraint sensor nodes. We evaluate the security performance of our proposal under different attack strategies through heuristic analysis, and show that our scheme achieves secure and robust replica detection by increasing the cost of node replication. Additionally, we evaluate the impact of network environment on the proposed scheme through theoretic analysis and simulation experiments, and indicate that our scheme achieves effectiveness and efficiency with substantially lower communication, computational, and storage overhead than prior works under different situations and attack strategies.

  2. Analysis of Wireless Sensor Network Topology and Estimation of Optimal Network Deployment by Deterministic Radio Channel Characterization

    Directory of Open Access Journals (Sweden)

    Erik Aguirre

    2015-02-01

    Full Text Available One of the main challenges in the implementation and design of context-aware scenarios is the adequate deployment strategy for Wireless Sensor Networks (WSNs, mainly due to the strong dependence of the radiofrequency physical layer with the surrounding media, which can lead to non-optimal network designs. In this work, radioplanning analysis for WSN deployment is proposed by employing a deterministic 3D ray launching technique in order to provide insight into complex wireless channel behavior in context-aware indoor scenarios. The proposed radioplanning procedure is validated with a testbed implemented with a Mobile Ad Hoc Network WSN following a chain configuration, enabling the analysis and assessment of a rich variety of parameters, such as received signal level, signal quality and estimation of power consumption. The adoption of deterministic radio channel techniques allows the design and further deployment of WSNs in heterogeneous wireless scenarios with optimized behavior in terms of coverage, capacity, quality of service and energy consumption.

  3. Deploying 5G-technologies in smart city and smart home wireless sensor networks with interferences

    DEFF Research Database (Denmark)

    Lynggaard, Per; Skouby, Knud Erik

    2015-01-01

    communication in an Internet of Things (5G) contexts. In this paper we discuss some of the key challenges that exist in the smart city and smart home networks in the light of possible 5G-solutions. Focus is on deploying cognitive radio technologies (5G) which enables the smart city networks to support......Deploying 5G technologies in a combination of smart homes and smart city opens for a new ecosystem with big potentials. The potentials lie in the creation of an advanced ICT infrastructure with support for connected and entangled services possibilities including technologies for efficient...... interconnected infrastructure elements, to handle big-data from the smart homes, and to be compatible with existing infrastructures. The considered cognitive radio technology is based on pre-coded OFDM which offers the needed flexibility to deal with the key challenges found in the smart home networks. Thus...

  4. Deployment of quasi-digital sensor for high temperature molten salt level measurement in pyroprocessing plants

    Science.gov (United States)

    Sanga, Ramesh; Agarwal, Sourabh; Sivaramakrishna, M.; Rao, G. Prabhakara

    2018-04-01

    Development of a liquid molten salt level sensor device that can detect the level of liquid molten salt in the process vessels of pyrochemical reprocessing of spent metallic fuels is detailed. It is proposed to apply a resistive-type pulsating sensor-based level measurement approach. There are no commercially available sensors due to limitations of high temperature, radiation, and physical dimensions. A compact, simple, rugged, low power, and high precise pulsating sensor-based level probe and simple instrumentation for the molten salt liquid level sensor to work in the extreme conditions has been indigenously developed, with high precision and accuracy. The working principle, design concept, and results have been discussed. This level probe is mainly composed of the variable resistor made up of ceramic rods. This resistor constitutes the part of resistance-capacitance-type Logic Gate Oscillator (LGO). A change in the molten salt level inside the tank causes a small change in the resistance which in turn changes the pulse frequency of the LGO. Thus the frequency, the output of the instrument that is displayed on the LCD of an embedded system, is a function of molten salt level. In the present design, the range of level measurement is about 10 mm. The sensitivity in position measurement up to 10 mm is ˜2.5 kHz/mm.

  5. Kinect Technology Game Play to Mimic Quake Catcher Network (QCN) Sensor Deployment During a Rapid Aftershock Mobilization Program (RAMP)

    Science.gov (United States)

    Kilb, D. L.; Yang, A.; Rohrlick, D.; Cochran, E. S.; Lawrence, J.; Chung, A. I.; Neighbors, C.; Choo, Y.

    2011-12-01

    The Kinect technology allows for hands-free game play, greatly increasing the accessibility of gaming for those uncomfortable using controllers. How it works is the Kinect camera transmits invisible near-infrared light and measures its "time of flight" to reflect off an object, allowing it to distinguish objects within 1 centimeter in depth and 3 mm in height and width. The middleware can also respond to body gestures and voice commands. Here, we use the Kinect Windows SDK software to create a game that mimics how scientists deploy seismic instruments following a large earthquake. The educational goal of the game is to allow the players to explore 3D space as they learn about the Quake Catcher Network's (QCN) Rapid Aftershock Mobilization Program (RAMP). Many of the scenarios within the game are taken from factual RAMP experiences. To date, only the PC platform (or a Mac running PC emulator software) is available for use, but we hope to move to other platforms (e.g., Xbox 360, iPad, iPhone) as they become available. The game is written in programming language C# using Microsoft XNA and Visual Studio 2010, graphic shading is added using High Level Shader Language (HLSL), and rendering is produced using XNA's graphics libraries. Key elements of the game include selecting sensor locations, adequately installing the sensor, and monitoring the incoming data. During game play aftershocks can occur unexpectedly, as can other problems that require attention (e.g., power outages, equipment failure, and theft). The player accrues points for quickly deploying the first sensor (recording as many initial aftershocks as possible), correctly installing the sensors (orientation with respect to north, properly securing, and testing), distributing the sensors adequately in the region, and troubleshooting problems. One can also net points for efficient use of game play time. Setting up for game play in your local environment requires: (1) the Kinect hardware ( $145); (2) a computer

  6. A field-deployable, aircraft-mounted sensor for the environmental survey of radionuclides

    International Nuclear Information System (INIS)

    Lepel, E.A.; Geelhood, B.D.; Hensley, W.K.; Quam, W.M.

    1998-01-01

    The Environmental Radionuclide Sensor System (ERSS) 3 is an extremely sensitive sensor, which has been cooperatively developed by Pacific Northwest National Laboratory (PNNL) and Special Technologies Laboratory (STL) for environmental surveys of radionuclides. The ERSS sensors fit in an airborne pod and include twenty High-Purity Germanium (HPGe) detectors for the high-resolution measurement of gamma-ray emitting radionuclides, twenty-four 3 He detectors for possible neutron measurements, and two video cameras for visual correlation. These aerial HPGe sensors provide much better gamma-ray energy resolution than can be obtained with NaI(Tl) detectors. The associated electronics fit into three racks. The system can be powered by the 28 V DC electrical supply of typical aircraft or 120 V AC. The data acquisition hardware is controlled by customized software and a real-time display is provided. Each gamma-ray event is time stamped and stored for later analysis. This paper will present the physical design, discuss the software used to control the system, and provide some examples of its use. (author)

  7. Feasibility of large-scale deployment of multiple wearable sensors in Parkinson's disease

    NARCIS (Netherlands)

    Silva de Lima, A.L.; Hahn, T.; Evers, L.J.W.; Vries, N.M. de; Cohen, E.; Afek, M.; Bataille, L.; Daeschler, M.; Claes, K.; Boroojerdi, B.; Terricabras, D.; Little, M.A.; Baldus, H.; Bloem, B.R.; Faber, M.J.

    2017-01-01

    Wearable devices can capture objective day-to-day data about Parkinson's Disease (PD). This study aims to assess the feasibility of implementing wearable technology to collect data from multiple sensors during the daily lives of PD patients. The Parkinson@home study is an observational, two-cohort

  8. Deployment of Low-Cost, Carbon Dioxide Sensors throughout the Washington Metropolitan Area - The Capital Climate Initiative

    Science.gov (United States)

    Caine, Kristen M.; Bailey, D. Michelle; Houston Miller, J.

    2016-04-01

    According to the IPCC from 1995 to 2005, atmospheric carbon dioxide (CO2) concentrations increased by 19 ppm, the highest average growth rate recorded for any decade since measurements began in the 1950s. Due to its ability to influence global climate change, it is imperative to continually monitor carbon dioxide emission levels, particularly in urban areas where some estimate in excess of 75% of total greenhouse gas emissions occur. Although high-precision sensors are commercially available, these are not cost effective for mapping a large spatial area. A goal of this research is to build out a network of sensors that are accurate and precise enough to provide a valuable data tool for accessing carbon emissions from a large, urban area. This publically available greenhouse gas dataset can be used in numerous environmental assessments and as validation for remote sensing products. It will also be a valuable teaching tool for classes at our university and will promote further engagement of K-12 students and their teachers through education and outreach activities. Each of our sensors (referred to as "PiOxides") utilizes a non-dispersive infrared (NDIR) sensor for the detection of carbon dioxide along with a combination pressure/temperature/humidity sensor. The collection of pressure and temperature increases the accuracy and precision of the CO2 measurement. The sensors communicate using a serial interfaces with a Raspberry Pi microcontroller. Each PiOxide is connected to a website that leverages recent developments in open source GIS tools. In this way, data from individual sensors can be followed individually or aggregated to provide real-time, spatially-resolved data of CO2 trends across a broad area. Our goal for the network is to expand across the entire DC/Maryland/Virginia Region through partnerships with private and public schools. We are also designing GHG Bluetooth beacons that may be accessed by mobile phone users in their vicinity. In two additional

  9. A Wireless Sensor Network Deployment for Rural and Forest Fire Detection and Verification

    Science.gov (United States)

    Lloret, Jaime; Garcia, Miguel; Bri, Diana; Sendra, Sandra

    2009-01-01

    Forest and rural fires are one of the main causes of environmental degradation in Mediterranean countries. Existing fire detection systems only focus on detection, but not on the verification of the fire. However, almost all of them are just simulations, and very few implementations can be found. Besides, the systems in the literature lack scalability. In this paper we show all the steps followed to perform the design, research and development of a wireless multisensor network which mixes sensors with IP cameras in a wireless network in order to detect and verify fire in rural and forest areas of Spain. We have studied how many cameras, sensors and access points are needed to cover a rural or forest area, and the scalability of the system. We have developed a multisensor and when it detects a fire, it sends a sensor alarm through the wireless network to a central server. The central server selects the closest wireless cameras to the multisensor, based on a software application, which are rotated to the sensor that raised the alarm, and sends them a message in order to receive real-time images from the zone. The camera lets the fire fighters corroborate the existence of a fire and avoid false alarms. In this paper, we show the test performance given by a test bench formed by four wireless IP cameras in several situations and the energy consumed when they are transmitting. Moreover, we study the energy consumed by each device when the system is set up. The wireless sensor network could be connected to Internet through a gateway and the images of the cameras could be seen from any part of the world. PMID:22291533

  10. A Wireless Sensor Network Deployment for Rural and Forest Fire Detection and Verification

    Directory of Open Access Journals (Sweden)

    Sandra Sendra

    2009-10-01

    Full Text Available Forest and rural fires are one of the main causes of environmental degradation in Mediterranean countries. Existing fire detection systems only focus on detection, but not on the verification of the fire. However, almost all of them are just simulations, and very few implementations can be found. Besides, the systems in the literature lack scalability. In this paper we show all the steps followed to perform the design, research and development of a wireless multisensor network which mixes sensors with IP cameras in a wireless network in order to detect and verify fire in rural and forest areas of Spain. We have studied how many cameras, sensors and access points are needed to cover a rural or forest area, and the scalability of the system. We have developed a multisensor and when it detects a fire, it sends a sensor alarm through the wireless network to a central server. The central server selects the closest wireless cameras to the multisensor, based on a software application, which are rotated to the sensor that raised the alarm, and sends them a message in order to receive real-time images from the zone. The camera lets the fire fighters corroborate the existence of a fire and avoid false alarms. In this paper, we show the test performance given by a test bench formed by four wireless IP cameras in several situations and the energy consumed when they are transmitting. Moreover, we study the energy consumed by each device when the system is set up. The wireless sensor network could be connected to Internet through a gateway and the images of the cameras could be seen from any part of the world.

  11. Lifetime Maximizing Adaptive Power Control in Wireless Sensor Networks

    National Research Council Canada - National Science Library

    Sun, Fangting; Shayman, Mark

    2006-01-01

    ...: adaptive power control. They focus on the sensor networks that consist of a sink and a set of homogeneous wireless sensor nodes, which are randomly deployed according to a uniform distribution...

  12. Wireless Sensors Grouping Proofs for Medical Care and Ambient Assisted-Living Deployment.

    Science.gov (United States)

    Trček, Denis

    2016-01-02

    Internet of Things (IoT) devices are rapidly penetrating e-health and assisted living domains, and an increasing proportion among them goes on the account of computationally-weak devices, where security and privacy provisioning alone are demanding tasks, not to mention grouping proofs. This paper, therefore, gives an extensive analysis of such proofs and states lessons learnt to avoid possible pitfalls in future designs. It sticks with prudent engineering techniques in this field and deploys in a novel way the so called non-deterministic principle to provide not only grouping proofs, but (among other) also privacy. The developed solution is analyzed by means of a tangible metric and it is shown to be lightweight, and formally for security.

  13. Wireless Sensors Grouping Proofs for Medical Care and Ambient Assisted-Living Deployment

    Directory of Open Access Journals (Sweden)

    Denis Trček

    2016-01-01

    Full Text Available Internet of Things (IoT devices are rapidly penetrating e-health and assisted living domains, and an increasing proportion among them goes on the account of computationally-weak devices, where security and privacy provisioning alone are demanding tasks, not to mention grouping proofs. This paper, therefore, gives an extensive analysis of such proofs and states lessons learnt to avoid possible pitfalls in future designs. It sticks with prudent engineering techniques in this field and deploys in a novel way the so called non-deterministic principle to provide not only grouping proofs, but (among other also privacy. The developed solution is analyzed by means of a tangible metric and it is shown to be lightweight, and formally for security.

  14. Random Access Performance of Distributed Sensors Attacked by Unknown Jammers

    Directory of Open Access Journals (Sweden)

    Dae-Kyo Jeong

    2017-11-01

    Full Text Available In this paper, we model and investigate the random access (RA performance of sensor nodes (SN in a wireless sensor network (WSN. In the WSN, a central head sensor (HS collects the information from distributed SNs, and jammers disturb the information transmission primarily by generating interference. In this paper, two jamming attacks are considered: power and code jamming. Power jammers (if they are friendly jammers generate noises and, as a result, degrade the quality of the signal from SNs. Power jamming is equally harmful to all the SNs that are accessing HS and simply induces denial of service (DoS without any need to hack HS or SNs. On the other hand, code jammers mimic legitimate SNs by sending fake signals and thus need to know certain system parameters that are used by the legitimate SNs. As a result of code jamming, HS falsely allocates radio resources to SNs. The code jamming hence increases the failure probability in sending the information messages, as well as misleads the usage of radio resources. In this paper, we present the probabilities of successful preamble transmission with power ramping according to the jammer types and provide the resulting throughput and delay of information transmission by SNs, respectively. The effect of two jamming attacks on the RA performances is compared with numerical investigation. The results show that, compared to RA without jammers, power and code jamming degrade the throughput by up to 30.3% and 40.5%, respectively, while the delay performance by up to 40.1% and 65.6%, respectively.

  15. Application of Wireless Sensor and Actuator Networks to Achieve Intelligent Microgrids: A Promising Approach towards a Global Smart Grid Deployment

    Directory of Open Access Journals (Sweden)

    Alvaro Llaria

    2016-02-01

    Full Text Available Smart Grids (SGs constitute the evolution of the traditional electrical grid towards a new paradigm, which should increase the reliability, the security and, at the same time, reduce the costs of energy generation, distribution and consumption. Electrical microgrids (MGs can be considered the first stage of this evolution of the grid, because of the intelligent management techniques that must be applied to assure their correct operation. To accomplish this task, sensors and actuators will be necessary, along with wireless communication technologies to transmit the measured data and the command messages. Wireless Sensor and Actuator Networks (WSANs are therefore a promising solution to achieve an intelligent management of MGs and, by extension, the SG. In this frame, this paper surveys several aspects concerning the application of WSANs to manage MGs and the electrical grid, as well as the communication protocols that could be applied. The main concerns regarding the SG deployment are also presented, including future scenarios where the interoperability of different generation technologies must be assured.

  16. A comprehensive remote automated mobile robot framework for deployment of compact radiation sensors and campaign management

    International Nuclear Information System (INIS)

    Mukherjee, J.K.

    2005-01-01

    Remote controlled on-line sensing with compact radiation sensors for interactive, fast contamination mapping and source localization needs integrated command control and machine intelligence supported operation. The combination of remote operation capability and automation of sensing needs a comprehensive framework encompassing precision real-time remote controlled agent, reliable remote communication techniques for unified command and sensory data exchange with optimized bandwidth allocation between the real time low volume as well as moderate speed bulk data transfer and data abstraction for seamless multi-domain abstraction in single environment. The paper describes an indigenously developed comprehensive framework that achieves vertical integration of layered services complex functions, explains its implementation and details its operation with examples of on-line application sessions. Several important features like precise remote control of sensor trajectory generation in real time by digital signal processing, prediction and visualization of remote agent locus and attitude, spatial modeling of fixed features of the monitored region and localization of activity source over mapped region have been dealt with. (author)

  17. Characterisation and deployment of an immobilised pH sensor spot towards surface ocean pH measurements.

    Science.gov (United States)

    Clarke, Jennifer S; Achterberg, Eric P; Rérolle, Victoire M C; Abi Kaed Bey, Samer; Floquet, Cedric F A; Mowlem, Matthew C

    2015-10-15

    The oceans are a major sink for anthropogenic atmospheric carbon dioxide, and the uptake causes changes to the marine carbonate system and has wide ranging effects on flora and fauna. It is crucial to develop analytical systems that allow us to follow the increase in oceanic pCO2 and corresponding reduction in pH. Miniaturised sensor systems using immobilised fluorescence indicator spots are attractive for this purpose because of their simple design and low power requirements. The technology is increasingly used for oceanic dissolved oxygen measurements. We present a detailed method on the use of immobilised fluorescence indicator spots to determine pH in ocean waters across the pH range 7.6-8.2. We characterised temperature (-0.046 pH/°C from 5 to 25 °C) and salinity dependences (-0.01 pH/psu over 5-35), and performed a preliminary investigation into the influence of chlorophyll on the pH measurement. The apparent pKa of the sensor spots was 6.93 at 20 °C. A drift of 0.00014 R (ca. 0.0004 pH, at 25 °C, salinity 35) was observed over a 3 day period in a laboratory based drift experiment. We achieved a precision of 0.0074 pH units, and observed a drift of 0.06 pH units during a test deployment of 5 week duration in the Southern Ocean as an underway surface ocean sensor, which was corrected for using certified reference materials. The temperature and salinity dependences were accounted for with the algorithm, R=0.00034-0.17·pH+0.15·S(2)+0.0067·T-0.0084·S·1.075. This study provides a first step towards a pH optode system suitable for autonomous deployment. The use of a short duration low power illumination (LED current 0.2 mA, 5 μs illumination time) improved the lifetime and precision of the spot. Further improvements to the pH indicator spot operations include regular application of certified reference materials for drift correction and cross-calibration against a spectrophotometric pH system. Desirable future developments should involve novel

  18. Distributed Detection with Collisions in a Random, Single-Hop Wireless Sensor Network

    Science.gov (United States)

    2013-05-26

    public release; distribution is unlimited. Distributed detection with collisions in a random, single-hop wireless sensor network The views, opinions...1274 2 ABSTRACT Distributed detection with collisions in a random, single-hop wireless sensor network Report Title We consider the problem of... WIRELESS SENSOR NETWORK Gene T. Whipps?† Emre Ertin† Randolph L. Moses† ?U.S. Army Research Laboratory, Adelphi, MD 20783 †The Ohio State University

  19. FEASIBILITY STUDY OF INEXPENSIVE THERMAL SENSORS AND SMALL UAS DEPLOYMENT FOR LIVING HUMAN DETECTION IN RESCUE MISSIONS APPLICATION SCENARIOS

    Directory of Open Access Journals (Sweden)

    E. Levin

    2016-06-01

    use SUAVs and small thermal sensors for the human detection scenarios described above. Differences in temperatures were collected by deployed imaging acquisition platform are interpretable on FLIR images visually. Moreover, we applied ENVI image processing functions for calibration and numerical estimations of such a temperature differences. There are more potential system functionalities such as voice messages from rescue teams and even distant medication delivery for the victims of described emergencies. This paper describes experiments, processing results, and future research in more details.

  20. Deployment Considerations for Low-cost Air Quality Sensor Networks; Examining Spatial Variability of Gas-Phase Pollutants Around a Building in Los Angeles

    Science.gov (United States)

    Collier-Oxandale, A. M.; Hannigan, M.; Casey, J. G.; Johnston, J.; Coffey, E.; Thorson, J.

    2017-12-01

    The field of low-cost air quality sensing technologies is growing rapidly through the continual development of new sensors, increased research into sensor performance, and more and more community groups utilizing sensors to investigate local issues. However, as this technology is still in an exploratory phase, there are few `best-practices' available to serve as guidelines for these projects and the standardization of some procedures could benefit the research community as a whole. For example, deployment considerations such as where and how to place a monitor at a given location are often determined by accessibility and safety, power-requirements, and what is an ideal for sampling the target pollutant. Using data from multiple gas-phase sensors, we will examine the importance of siting considerations for low-cost monitoring systems. During a sampling campaign in Los Angeles, a subset of monitors was deployed at one field site to explore the variability in air quality sensor data around a single building. The site is a three story, multi-family housing unit in a primarily residential neighborhood that is near two major roadways and other potential sources of pollution. Five low-cost monitors were co-located prior to and following the field deployment. During the approximately 2.5-month deployment, these monitors were placed at various heights above street level, on different sides of the building, and on the roof. In our analysis, we will examine how monitor placement affects a sensor's ability to detect local verses more regional trends and how this building-scale spatial variability changes over time. Additionally, examining data from VOC sensors (quantified for methane and total non-methane hydrocarbon signals) and O3 sensors will allow us to compare the variability of primary and secondary pollutants. An outcome of this analysis may include guidelines or `best practices' for siting sensors that could aid in ensuring the collection of high quality field data

  1. Comparing Building and Neighborhood-Scale Variability of CO₂ and O₃ to Inform Deployment Considerations for Low-Cost Sensor System Use.

    Science.gov (United States)

    Collier-Oxandale, Ashley; Coffey, Evan; Thorson, Jacob; Johnston, Jill; Hannigan, Michael

    2018-04-26

    The increased use of low-cost air quality sensor systems, particularly by communities, calls for the further development of best-practices to ensure these systems collect usable data. One area identified as requiring more attention is that of deployment logistics, that is, how to select deployment sites and how to strategically place sensors at these sites. Given that sensors are often placed at homes and businesses, ideal placement is not always possible. Considerations such as convenience, access, aesthetics, and safety are also important. To explore this issue, we placed multiple sensor systems at an existing field site allowing us to examine both neighborhood-level and building-level variability during a concurrent period for CO₂ (a primary pollutant) and O₃ (a secondary pollutant). In line with previous studies, we found that local and transported emissions as well as thermal differences in sensor systems drive variability, particularly for high-time resolution data. While this level of variability is unlikely to affect data on larger averaging scales, this variability could impact analysis if the user is interested in high-time resolution or examining local sources. However, with thoughtful placement and thorough documentation, high-time resolution data at the neighborhood level has the potential to provide us with entirely new information on local air quality trends and emissions.

  2. A Depth-Adjustment Deployment Algorithm Based on Two-Dimensional Convex Hull and Spanning Tree for Underwater Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Peng Jiang

    2016-07-01

    Full Text Available Most of the existing node depth-adjustment deployment algorithms for underwater wireless sensor networks (UWSNs just consider how to optimize network coverage and connectivity rate. However, these literatures don’t discuss full network connectivity, while optimization of network energy efficiency and network reliability are vital topics for UWSN deployment. Therefore, in this study, a depth-adjustment deployment algorithm based on two-dimensional (2D convex hull and spanning tree (NDACS for UWSNs is proposed. First, the proposed algorithm uses the geometric characteristics of a 2D convex hull and empty circle to find the optimal location of a sleep node and activate it, minimizes the network coverage overlaps of the 2D plane, and then increases the coverage rate until the first layer coverage threshold is reached. Second, the sink node acts as a root node of all active nodes on the 2D convex hull and then forms a small spanning tree gradually. Finally, the depth-adjustment strategy based on time marker is used to achieve the three-dimensional overall network deployment. Compared with existing depth-adjustment deployment algorithms, the simulation results show that the NDACS algorithm can maintain full network connectivity with high network coverage rate, as well as improved network average node degree, thus increasing network reliability.

  3. Impact of High Power Interference Sources in Planning and Deployment of Wireless Sensor Networks and Devices in the 2.4 GHz Frequency Band in Heterogeneous Environments

    Directory of Open Access Journals (Sweden)

    Francisco Falcone

    2012-11-01

    Full Text Available In this work, the impact of radiofrequency radiation leakage from microwave ovens and its effect on 802.15.4 ZigBee-compliant wireless sensor networks operating in the 2.4 GHz Industrial Scientific Medical (ISM band is analyzed. By means of a novel radioplanning approach, based on electromagnetic field simulation of a microwave oven and determination of equivalent radiation sources applied to an in-house developed 3D ray launching algorithm, estimation of the microwave oven’s power leakage is obtained for the complete volume of an indoor scenario. The magnitude and the variable nature of the interference is analyzed and the impact in the radio link quality in operating wireless sensors is estimated and compared with radio channel measurements as well as packet measurements. The measurement results reveal the importance of selecting an adequate 802.15.4 channel, as well as the Wireless Sensor Network deployment strategy within this type of environment, in order to optimize energy consumption and increase the overall network performance. The proposed method enables one to estimate potential interference effects in devices operating within the 2.4 GHz band in the complete scenario, prior to wireless sensor network deployment, which can aid in achieving the most optimal network topology.

  4. Moored ADCP current data from deployment 2 of the Multi-disciplinary Ocean Sensors for Environmental Analyses and Networks (MOSEAN) project north of Hawaii 2004-2005 (NODC Accession 0116094)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — ADCP data were collected by sensors from seven deployments within 2004-2007 on the HALE-ALOHA mooring, a location about 100 km north of Oahu, Hawaii, USA. The...

  5. Construction and Deployment of Tilt Sensors along the Lateral Margins of Jarvis Glacier, Alaska to improve understanding of the Deformation Regime of Wet-Based Polythermal Glaciers

    Science.gov (United States)

    Lee, I. R.; Hawley, R. L.; Clemens-Sewall, D.; Campbell, S. W.; Waszkiewicz, M.; Bernsen, S.; Gerbi, C. C.; Kreutz, K. J.; Koons, P. O.

    2017-12-01

    Most studies of natural ice have been on bodies of ice with frozen beds which experience minimal lateral shear strain, to the exclusion of polythermal ice sheets & glaciers which due to their mixed basal thermal regime have wet-based beds. The deficiency in knowledge and understanding of the operative deformation mechanisms of wet-based bodies of ice results in uncertainty in the constitutive flow law of ice. Given that the flow law was derived experimentally under assumptions more conducive to bodies of ice with frozen-based beds, it is necessary to calibrate the flow law when applied to different bodies of ice such as wet-based polythermal glaciers. To this end, Dartmouth and the University of Maine have collaborated to carry out research on Jarvis Glacier in Alaska, a geometrically simple, wet-based glacier. Here, we constructed and deployed an array of 25 tilt sensors into 3 boreholes drilled along the glacier's shear margin. Our goal is to obtain 3D strain measurements to calculate the full velocity field & create deformation regime maps in the vicinity of the boreholes, as well as to support numerical modeling. The tilt sensors were developed in-lab: Each tilt sensor comes equipped with an LSM303C chip (embedded with a 3-axis accelerometer and magnetometer) and Arduino Pro-Mini mounted on a custom-made printed circuit board encased within a watertight aluminum tube. The design concept was to produce a sensor string, consisting of tilt sensors spaced apart at pre-calculated intervals, to be lowered into a borehole and frozen-in over months to collect strain data through a Campbell Scientific CR1000 datalogger. Three surface-to-bed boreholes were successfully installed with tilt sensor strings. Given the lack of prior in-situ borehole geophysics studies on polythermal glaciers, deliberate consideration on factors such as strain relief and waterproofing electrical components was necessary in the development of the sensor system. On-site challenges also arose due

  6. Mutual trust method for forwarding information in wireless sensor networks using random secret pre-distribution

    Directory of Open Access Journals (Sweden)

    Chih-Hsueh Lin

    2016-04-01

    Full Text Available In wireless sensor networks, sensing information must be transmitted from sensor nodes to the base station by multiple hopping. Every sensor node is a sender and a relay node that forwards the sensing information that is sent by other nodes. Under an attack, the sensing information may be intercepted, modified, interrupted, or fabricated during transmission. Accordingly, the development of mutual trust to enable a secure path to be established for forwarding information is an important issue. Random key pre-distribution has been proposed to establish mutual trust among sensor nodes. This article modifies the random key pre-distribution to a random secret pre-distribution and incorporates identity-based cryptography to establish an effective method of establishing mutual trust for a wireless sensor network. In the proposed method, base station assigns an identity and embeds n secrets into the private secret keys for every sensor node. Based on the identity and private secret keys, the mutual trust method is utilized to explore the types of trust among neighboring sensor nodes. The novel method can resist malicious attacks and satisfy the requirements of wireless sensor network, which are resistance to compromising attacks, masquerading attacks, forger attacks, replying attacks, authentication of forwarding messages, and security of sensing information.

  7. Epidermis Microstructure Inspired Graphene Pressure Sensor with Random Distributed Spinosum for High Sensitivity and Large Linearity.

    Science.gov (United States)

    Pang, Yu; Zhang, Kunning; Yang, Zhen; Jiang, Song; Ju, Zhenyi; Li, Yuxing; Wang, Xuefeng; Wang, Danyang; Jian, Muqiang; Zhang, Yingying; Liang, Renrong; Tian, He; Yang, Yi; Ren, Tian-Ling

    2018-03-27

    Recently, wearable pressure sensors have attracted tremendous attention because of their potential applications in monitoring physiological signals for human healthcare. Sensitivity and linearity are the two most essential parameters for pressure sensors. Although various designed micro/nanostructure morphologies have been introduced, the trade-off between sensitivity and linearity has not been well balanced. Human skin, which contains force receptors in a reticular layer, has a high sensitivity even for large external stimuli. Herein, inspired by the skin epidermis with high-performance force sensing, we have proposed a special surface morphology with spinosum microstructure of random distribution via the combination of an abrasive paper template and reduced graphene oxide. The sensitivity of the graphene pressure sensor with random distribution spinosum (RDS) microstructure is as high as 25.1 kPa -1 in a wide linearity range of 0-2.6 kPa. Our pressure sensor exhibits superior comprehensive properties compared with previous surface-modified pressure sensors. According to simulation and mechanism analyses, the spinosum microstructure and random distribution contribute to the high sensitivity and large linearity range, respectively. In addition, the pressure sensor shows promising potential in detecting human physiological signals, such as heartbeat, respiration, phonation, and human motions of a pushup, arm bending, and walking. The wearable pressure sensor array was further used to detect gait states of supination, neutral, and pronation. The RDS microstructure provides an alternative strategy to improve the performance of pressure sensors and extend their potential applications in monitoring human activities.

  8. A machine learning calibration model using random forests to improve sensor performance for lower-cost air quality monitoring

    Science.gov (United States)

    Zimmerman, Naomi; Presto, Albert A.; Kumar, Sriniwasa P. N.; Gu, Jason; Hauryliuk, Aliaksei; Robinson, Ellis S.; Robinson, Allen L.; Subramanian, R.

    2018-01-01

    Low-cost sensing strategies hold the promise of denser air quality monitoring networks, which could significantly improve our understanding of personal air pollution exposure. Additionally, low-cost air quality sensors could be deployed to areas where limited monitoring exists. However, low-cost sensors are frequently sensitive to environmental conditions and pollutant cross-sensitivities, which have historically been poorly addressed by laboratory calibrations, limiting their utility for monitoring. In this study, we investigated different calibration models for the Real-time Affordable Multi-Pollutant (RAMP) sensor package, which measures CO, NO2, O3, and CO2. We explored three methods: (1) laboratory univariate linear regression, (2) empirical multiple linear regression, and (3) machine-learning-based calibration models using random forests (RF). Calibration models were developed for 16-19 RAMP monitors (varied by pollutant) using training and testing windows spanning August 2016 through February 2017 in Pittsburgh, PA, US. The random forest models matched (CO) or significantly outperformed (NO2, CO2, O3) the other calibration models, and their accuracy and precision were robust over time for testing windows of up to 16 weeks. Following calibration, average mean absolute error on the testing data set from the random forest models was 38 ppb for CO (14 % relative error), 10 ppm for CO2 (2 % relative error), 3.5 ppb for NO2 (29 % relative error), and 3.4 ppb for O3 (15 % relative error), and Pearson r versus the reference monitors exceeded 0.8 for most units. Model performance is explored in detail, including a quantification of model variable importance, accuracy across different concentration ranges, and performance in a range of monitoring contexts including the National Ambient Air Quality Standards (NAAQS) and the US EPA Air Sensors Guidebook recommendations of minimum data quality for personal exposure measurement. A key strength of the RF approach is that

  9. Rich: Region-based Intelligent Cluster-Head Selection and Node Deployment Strategy in Concentric-based WSNs

    Directory of Open Access Journals (Sweden)

    FAN, C.-S.

    2013-11-01

    Full Text Available In a random deployment, sensor nodes are scattered randomly in the sensing field. Hence, the coverage can not be guaranteed. In contrast, the coverage of uniformly deployment is in general larger than the random deployment. However, uniformly deployment strategy may cause unbalanced traffic pattern in wireless sensor networks (WSNs. In this situation, larger load may be imposed to CHs (cluster heads around the sink. Therefore, CHs close to the sink use up their energy earlier than those farther away from the sink. To overcome this problem, we propose a novel node deployment strategy in the concentric model, namely, Region-based Intelligent Cluster-Head selection and node deployment strategy (called Rich. The coverage, energy consumption and data routing issues are well investigated and taken into consideration in the proposed Rich scheme. The simulation results show that the proposed Rich alleviates the unbalanced traffic pattern significantly, prolongs network lifetime and achieves satisfactory coverage ratio.

  10. Multi-parameter sensor based on random fiber lasers

    Directory of Open Access Journals (Sweden)

    Yanping Xu

    2016-09-01

    Full Text Available We demonstrate a concept of utilizing random fiber lasers to achieve multi-parameter sensing. The proposed random fiber ring laser consists of an erbium-doped fiber as the gain medium and a random fiber grating as the feedback. The random feedback is effectively realized by a large number of reflections from around 50000 femtosecond laser induced refractive index modulation regions over a 10cm standard single mode fiber. Numerous polarization-dependent spectral filters are formed and superimposed to provide multiple lasing lines with high signal-to-noise ratio up to 40dB, which gives an access for a high-fidelity multi-parameter sensing scheme. The number of sensing parameters can be controlled by the number of the lasing lines via input polarizations and wavelength shifts of each peak can be explored for the simultaneous multi-parameter sensing with one sensing probe. In addition, the random grating induced coupling between core and cladding modes can be potentially used for liquid medical sample sensing in medical diagnostics, biology and remote sensing in hostile environments.

  11. Deployment and evaluation of a dual-sensor autofocusing method for on-machine measurement of patterns of small holes on freeform surfaces.

    Science.gov (United States)

    Chen, Xiaomei; Longstaff, Andrew; Fletcher, Simon; Myers, Alan

    2014-04-01

    This paper presents and evaluates an active dual-sensor autofocusing system that combines an optical vision sensor and a tactile probe for autofocusing on arrays of small holes on freeform surfaces. The system has been tested on a two-axis test rig and then integrated onto a three-axis computer numerical control (CNC) milling machine, where the aim is to rapidly and controllably measure the hole position errors while the part is still on the machine. The principle of operation is for the tactile probe to locate the nominal positions of holes, and the optical vision sensor follows to focus and capture the images of the holes. The images are then processed to provide hole position measurement. In this paper, the autofocusing deviations are analyzed. First, the deviations caused by the geometric errors of the axes on which the dual-sensor unit is deployed are estimated to be 11 μm when deployed on a test rig and 7 μm on the CNC machine tool. Subsequently, the autofocusing deviations caused by the interaction of the tactile probe, surface, and small hole are mathematically analyzed and evaluated. The deviations are a result of the tactile probe radius, the curvatures at the positions where small holes are drilled on the freeform surface, and the effect of the position error of the hole on focusing. An example case study is provided for the measurement of a pattern of small holes on an elliptical cylinder on the two machines. The absolute sum of the autofocusing deviations is 118 μm on the test rig and 144 μm on the machine tool. This is much less than the 500 μm depth of field of the optical microscope. Therefore, the method is capable of capturing a group of clear images of the small holes on this workpiece for either implementation.

  12. Randomized Trial of Intelligent Sensor System for Early Illness Alerts in Senior Housing.

    Science.gov (United States)

    Rantz, Marilyn; Phillips, Lorraine J; Galambos, Colleen; Lane, Kari; Alexander, Gregory L; Despins, Laurel; Koopman, Richelle J; Skubic, Marjorie; Hicks, Lanis; Miller, Steven; Craver, Andy; Harris, Bradford H; Deroche, Chelsea B

    2017-10-01

    Measure the clinical effectiveness and cost effectiveness of using sensor data from an environmentally embedded sensor system for early illness recognition. This sensor system has demonstrated in pilot studies to detect changes in function and in chronic diseases or acute illnesses on average 10 days to 2 weeks before usual assessment methods or self-reports of illness. Prospective intervention study in 13 assisted living (AL) communities of 171 residents randomly assigned to intervention (n=86) or comparison group (n=85) receiving usual care. Intervention participants lived with the sensor system an average of one year. Continuous data collected 24 hours/7 days a week from motion sensors to measure overall activity, an under mattress bed sensor to capture respiration, pulse, and restlessness as people sleep, and a gait sensor that continuously measures gait speed, stride length and time, and automatically assess for increasing fall risk as the person walks around the apartment. Continuously running computer algorithms are applied to the sensor data and send health alerts to staff when there are changes in sensor data patterns. The randomized comparison group functionally declined more rapidly than the intervention group. Walking speed and several measures from GaitRite, velocity, step length left and right, stride length left and right, and the fall risk measure of functional ambulation profile (FAP) all had clinically significant changes. The walking speed increase (worse) and velocity decline (worse) of 0.073 m/s for comparison group exceeded 0.05 m/s, a value considered to be a minimum clinically important difference. No differences were measured in health care costs. These findings demonstrate that sensor data with health alerts and fall alerts sent to AL nursing staff can be an effective strategy to detect and intervene in early signs of illness or functional decline. Copyright © 2017 AMDA – The Society for Post-Acute and Long-Term Care Medicine. Published

  13. Cell Selection Game for Densely-Deployed Sensor and Mobile Devices In 5G Networks Integrating Heterogeneous Cells and the Internet of Things

    Science.gov (United States)

    Wang, Lusheng; Wang, Yamei; Ding, Zhizhong; Wang, Xiumin

    2015-01-01

    With the rapid development of wireless networking technologies, the Internet of Things and heterogeneous cellular networks (HCNs) tend to be integrated to form a promising wireless network paradigm for 5G. Hyper-dense sensor and mobile devices will be deployed under the coverage of heterogeneous cells, so that each of them could freely select any available cell covering it and compete for resource with others selecting the same cell, forming a cell selection (CS) game between these devices. Since different types of cells usually share the same portion of the spectrum, devices selecting overlapped cells can experience severe inter-cell interference (ICI). In this article, we study the CS game among a large amount of densely-deployed sensor and mobile devices for their uplink transmissions in a two-tier HCN. ICI is embedded with the traditional congestion game (TCG), forming a congestion game with ICI (CGI) and a congestion game with capacity (CGC). For the three games above, we theoretically find the circular boundaries between the devices selecting the macrocell and those selecting the picocells, indicated by the pure strategy Nash equilibria (PSNE). Meanwhile, through a number of simulations with different picocell radii and different path loss exponents, the collapse of the PSNE impacted by severe ICI (i.e., a large number of picocell devices change their CS preferences to the macrocell) is profoundly revealed, and the collapse points are identified. PMID:26393617

  14. Cell Selection Game for Densely-Deployed Sensor and Mobile Devices In 5G Networks Integrating Heterogeneous Cells and the Internet of Things

    Directory of Open Access Journals (Sweden)

    Lusheng Wang

    2015-09-01

    Full Text Available With the rapid development of wireless networking technologies, the Internet of Things and heterogeneous cellular networks (HCNs tend to be integrated to form a promising wireless network paradigm for 5G. Hyper-dense sensor and mobile devices will be deployed under the coverage of heterogeneous cells, so that each of them could freely select any available cell covering it and compete for resource with others selecting the same cell, forming a cell selection (CS game between these devices. Since different types of cells usually share the same portion of the spectrum, devices selecting overlapped cells can experience severe inter-cell interference (ICI. In this article, we study the CS game among a large amount of densely-deployed sensor and mobile devices for their uplink transmissions in a two-tier HCN. ICI is embedded with the traditional congestion game (TCG, forming a congestion game with ICI (CGI and a congestion game with capacity (CGC. For the three games above, we theoretically find the circular boundaries between the devices selecting the macrocell and those selecting the picocells, indicated by the pure strategy Nash equilibria (PSNE. Meanwhile, through a number of simulations with different picocell radii and different path loss exponents, the collapse of the PSNE impacted by severe ICI (i.e., a large number of picocell devices change their CS preferences to the macrocell is profoundly revealed, and the collapse points are identified.

  15. Cell Selection Game for Densely-Deployed Sensor and Mobile Devices In 5G Networks Integrating Heterogeneous Cells and the Internet of Things.

    Science.gov (United States)

    Wang, Lusheng; Wang, Yamei; Ding, Zhizhong; Wang, Xiumin

    2015-09-18

    With the rapid development of wireless networking technologies, the Internet of Things and heterogeneous cellular networks (HCNs) tend to be integrated to form a promising wireless network paradigm for 5G. Hyper-dense sensor and mobile devices will be deployed under the coverage of heterogeneous cells, so that each of them could freely select any available cell covering it and compete for resource with others selecting the same cell, forming a cell selection (CS) game between these devices. Since different types of cells usually share the same portion of the spectrum, devices selecting overlapped cells can experience severe inter-cell interference (ICI). In this article, we study the CS game among a large amount of densely-deployed sensor and mobile devices for their uplink transmissions in a two-tier HCN. ICI is embedded with the traditional congestion game (TCG), forming a congestion game with ICI (CGI) and a congestion game with capacity (CGC). For the three games above, we theoretically find the circular boundaries between the devices selecting the macrocell and those selecting the picocells, indicated by the pure strategy Nash equilibria (PSNE). Meanwhile, through a number of simulations with different picocell radii and different path loss exponents, the collapse of the PSNE impacted by severe ICI (i.e., a large number of picocell devices change their CS preferences to the macrocell) is profoundly revealed, and the collapse points are identified.

  16. Development and deployment of a low-cost, mobile-ready, air quality sensor system: progress toward distributed networks and autonomous aerial sampling

    Science.gov (United States)

    Hersey, S. P.; DiVerdi, R.; Gadtaula, P.; Sheneman, T.; Flores, K.; Chen, Y. H.; Jayne, J. T.; Cross, E. S.

    2017-12-01

    Throughout the 2016-2017 academic year, a new partnership between Olin College of Engineering and Aerodyne Research, Inc. developed an affordable, self-contained air quality monitoring instrument called Modulair. The Modulair instrument is based on the same operating principles as Aerodyne's newly-developed ARISense integrated sensor system, employing electrochemical sensors for gas-phase measurements of CO, NO, NO2, and O3 and an off-the-shelf optical particle counter for particle concentration, number, and size distribution information (0.4 backend with a mobile, cloud-based data management system for real-time data posting and analysis. Open source tools and software were utilized in the development of the instrument. All initial work was completed by a team of undergraduate students as part of the Senior Capstone Program in Engineering (SCOPE) at Olin College. Deployment strategies for Modulair include distributed, mobile measurements and drone-based aerial sampling. Design goals for the drone integration include maximizing airborne sampling time and laying the foundation for software integration with the drone's autopilot system to allow for autonomous plume sampling across concentration gradients. Modulair and its flexible deployments enable real-time mapping of air quality data at exposure-relevant spatial scales, as well as regular, autonomous characterization of sources and dispersion of atmospheric pollutants. We will present an overview of the Modulair instrument and results from benchtop and field validation, including mobile and drone-based plume sampling in the Boston area.

  17. Pulse oximeter sensor application during neonatal resuscitation: a randomized controlled trial.

    Science.gov (United States)

    Louis, Deepak; Sundaram, Venkataseshan; Kumar, Praveen

    2014-03-01

    This study was done to compare 2 techniques of pulse oximeter sensor application during neonatal resuscitation for faster signal detection. Sensor to infant first (STIF) and then to oximeter was compared with sensor to oximeter first (STOF) and then to infant in ≥28 weeks gestations. The primary outcome was time from completion of sensor application to reliable signal, defined as stable display of heart rate and saturation. Time from birth to sensor application, time taken for sensor application, time from birth to reliable signal, and need to reapply sensor were secondary outcomes. An intention-to-treat analysis was done, and subgroup analysis was done for gestation and need for resuscitation. One hundred fifty neonates were randomized with 75 to each technique. The median (IQR) time from sensor application to detection of reliable signal was longer in STIF group compared with STOF group (16 [15-17] vs. 10 [6-18] seconds; P signal did not differ between the 2 methods (STIF: 61 [52-76] seconds; STOF: 58 [47-73] seconds [P = .09]). Time taken for signal acquisition was longer with STIF than with STOF in both subgroups. In the delivery room setting, the STOF method recognized saturation and heart rate faster than the STIF method. The time from birth to reliable signal was similar with the 2 methods.

  18. Adaptive and Reactive Security for Wireless Sensor Networks

    National Research Council Canada - National Science Library

    Stankovic, John A

    2007-01-01

    .... WSNs are also susceptible to malicious, non-random security attacks. For example, a wireless sensor network deployed in remote regions to detect and classify targets could be rendered inoperative by various security attacks...

  19. Fully-distributed randomized cooperation in wireless sensor networks

    KAUST Repository

    Bader, Ahmed

    2015-01-07

    When marrying randomized distributed space-time coding (RDSTC) to geographical routing, new performance horizons can be created. In order to reach those horizons however, routing protocols must evolve to operate in a fully distributed fashion. In this letter, we expose a technique to construct a fully distributed geographical routing scheme in conjunction with RDSTC. We then demonstrate the performance gains of this novel scheme by comparing it to one of the prominent classical schemes.

  20. Fully-distributed randomized cooperation in wireless sensor networks

    KAUST Repository

    Bader, Ahmed; Abed-Meraim, Karim; Alouini, Mohamed-Slim

    2015-01-01

    When marrying randomized distributed space-time coding (RDSTC) to geographical routing, new performance horizons can be created. In order to reach those horizons however, routing protocols must evolve to operate in a fully distributed fashion. In this letter, we expose a technique to construct a fully distributed geographical routing scheme in conjunction with RDSTC. We then demonstrate the performance gains of this novel scheme by comparing it to one of the prominent classical schemes.

  1. Clustering algorithm in initialization of multi-hop wireless sensor networks

    NARCIS (Netherlands)

    Guo, Peng; Tao, Jiang; Zhang, Kui; Chen, Hsiao-Hwa

    2009-01-01

    In most application scenarios of wireless sensor networks (WSN), sensor nodes are usually deployed randomly and do not have any knowledge about the network environment or even their ID's at the initial stage of their operations. In this paper, we address the clustering problems with a newly deployed

  2. Autoregressive Modeling of Drift and Random Error to Characterize a Continuous Intravascular Glucose Monitoring Sensor.

    Science.gov (United States)

    Zhou, Tony; Dickson, Jennifer L; Geoffrey Chase, J

    2018-01-01

    Continuous glucose monitoring (CGM) devices have been effective in managing diabetes and offer potential benefits for use in the intensive care unit (ICU). Use of CGM devices in the ICU has been limited, primarily due to the higher point accuracy errors over currently used traditional intermittent blood glucose (BG) measures. General models of CGM errors, including drift and random errors, are lacking, but would enable better design of protocols to utilize these devices. This article presents an autoregressive (AR) based modeling method that separately characterizes the drift and random noise of the GlySure CGM sensor (GlySure Limited, Oxfordshire, UK). Clinical sensor data (n = 33) and reference measurements were used to generate 2 AR models to describe sensor drift and noise. These models were used to generate 100 Monte Carlo simulations based on reference blood glucose measurements. These were then compared to the original CGM clinical data using mean absolute relative difference (MARD) and a Trend Compass. The point accuracy MARD was very similar between simulated and clinical data (9.6% vs 9.9%). A Trend Compass was used to assess trend accuracy, and found simulated and clinical sensor profiles were similar (simulated trend index 11.4° vs clinical trend index 10.9°). The model and method accurately represents cohort sensor behavior over patients, providing a general modeling approach to any such sensor by separately characterizing each type of error that can arise in the data. Overall, it enables better protocol design based on accurate expected CGM sensor behavior, as well as enabling the analysis of what level of each type of sensor error would be necessary to obtain desired glycemic control safety and performance with a given protocol.

  3. Kalman Filtering for Discrete Stochastic Systems with Multiplicative Noises and Random Two-Step Sensor Delays

    Directory of Open Access Journals (Sweden)

    Dongyan Chen

    2015-01-01

    Full Text Available This paper is concerned with the optimal Kalman filtering problem for a class of discrete stochastic systems with multiplicative noises and random two-step sensor delays. Three Bernoulli distributed random variables with known conditional probabilities are introduced to characterize the phenomena of the random two-step sensor delays which may happen during the data transmission. By using the state augmentation approach and innovation analysis technique, an optimal Kalman filter is constructed for the augmented system in the sense of the minimum mean square error (MMSE. Subsequently, the optimal Kalman filtering is derived for corresponding augmented system in initial instants. Finally, a simulation example is provided to demonstrate the feasibility and effectiveness of the proposed filtering method.

  4. A Model for Field Deployment of Wireless Sensor Networks (WSNs) within the Domain of Microclimate Habitat Monitoring

    Science.gov (United States)

    Sanborn, Mark

    2011-01-01

    Wireless sensor networks (WSNs) represent a class of miniaturized information systems designed to monitor physical environments. These smart monitoring systems form collaborative networks utilizing autonomous sensing, data-collection, and processing to provide real-time analytics of observed environments. As a fundamental research area in…

  5. Distributed parallel cooperative coevolutionary multi-objective large-scale immune algorithm for deployment of wireless sensor networks

    DEFF Research Database (Denmark)

    Cao, Bin; Zhao, Jianwei; Yang, Po

    2018-01-01

    -objective evolutionary algorithms the Cooperative Coevolutionary Generalized Differential Evolution 3, the Cooperative Multi-objective Differential Evolution and the Nondominated Sorting Genetic Algorithm III, the proposed algorithm addresses the deployment optimization problem efficiently and effectively.......Using immune algorithms is generally a time-intensive process especially for problems with a large number of variables. In this paper, we propose a distributed parallel cooperative coevolutionary multi-objective large-scale immune algorithm that is implemented using the message passing interface...... (MPI). The proposed algorithm is composed of three layers: objective, group and individual layers. First, for each objective in the multi-objective problem to be addressed, a subpopulation is used for optimization, and an archive population is used to optimize all the objectives. Second, the large...

  6. Dynamic Load Balanced Clustering using Elitism based Random Immigrant Genetic Approach for Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    K. Mohaideen Pitchai

    2017-07-01

    Full Text Available Wireless Sensor Network (WSN consists of a large number of small sensors with restricted energy. Prolonged network lifespan, scalability, node mobility and load balancing are important needs for several WSN applications. Clustering the sensor nodes is an efficient technique to reach these goals. WSN have the characteristics of topology dynamics because of factors like energy conservation and node movement that leads to Dynamic Load Balanced Clustering Problem (DLBCP. In this paper, Elitism based Random Immigrant Genetic Approach (ERIGA is proposed to solve DLBCP which adapts to topology dynamics. ERIGA uses the dynamic Genetic Algorithm (GA components for solving the DLBCP. The performance of load balanced clustering process is enhanced with the help of this dynamic GA. As a result, the ERIGA achieves to elect suitable cluster heads which balances the network load and increases the lifespan of the network.

  7. Spouse READI (Resilience Education and Deployment Information): Randomized Clinical Trial Formerly Reintegration: The Role of Spouse Telephone BATTLEMIND Randomized Clinical Trial

    Science.gov (United States)

    2014-10-01

    OIF and Operation New Dawn - OND) and Afghanistan (Operation Enduring Freedom – OEF). The goal was to build spouses’ resilience to cope with...mental or physical health, self- reported/perceived health, medical conditions (diabetes, depressive symptoms, hypertension , heart disease, cancer...at least one month post deployment from serving in Iraq (Operation Iraqi Freedom – OIF, Operation New Dawn – OND) or Afghanistan (Operation Enduring

  8. Effect of Deploying Trained Community Based Reproductive Health Nurses (CORN) on Long-Acting Reversible Contraception (LARC) Use in Rural Ethiopia: A Cluster Randomized Community Trial.

    Science.gov (United States)

    Zerfu, Taddese Alemu; Ayele, Henok Taddese; Bogale, Tariku Nigatu

    2018-06-01

    To investigate the effect of innovative means to distribute LARC on contraceptive use, we implemented a three arm, parallel groups, cluster randomized community trial design. The intervention consisted of placing trained community-based reproductive health nurses (CORN) within health centers or health posts. The nurses provided counseling to encourage women to use LARC and distributed all contraceptive methods. A total of 282 villages were randomly selected and assigned to a control arm (n = 94) or 1 of 2 treatment arms (n = 94 each). The treatment groups differed by where the new service providers were deployed, health post or health center. We calculated difference-in-difference (DID) estimates to assess program impacts on LARC use. After nine months of intervention, the use of LARC methods increased significantly by 72.3 percent, while the use of short acting methods declined by 19.6 percent. The proportion of women using LARC methods increased by 45.9 percent and 45.7 percent in the health post and health center based intervention arms, respectively. Compared to the control group, the DID estimates indicate that the use of LARC methods increased by 11.3 and 12.3 percentage points in the health post and health center based intervention arms. Given the low use of LARC methods in similar settings, deployment of contextually trained nurses at the grassroots level could substantially increase utilization of these methods. © 2018 The Population Council, Inc.

  9. Sleep Deprivation Attack Detection in Wireless Sensor Network

    OpenAIRE

    Bhattasali, Tapalina; Chaki, Rituparna; Sanyal, Sugata

    2012-01-01

    Deployment of sensor network in hostile environment makes it mainly vulnerable to battery drainage attacks because it is impossible to recharge or replace the battery power of sensor nodes. Among different types of security threats, low power sensor nodes are immensely affected by the attacks which cause random drainage of the energy level of sensors, leading to death of the nodes. The most dangerous type of attack in this category is sleep deprivation, where target of the intruder is to maxi...

  10. Deployment Repeatability

    Science.gov (United States)

    2016-04-01

    evaluating the deployment repeatability builds upon the testing or analysis of deployment kinematics (Chapter 6) and adds repetition. Introduction...material yield or failure during a test. For the purposes of this chapter, zero shift will refer to permanent changes in the structure, while reversible ...the content of other chapters in this book: Gravity Compensation (Chapter 4) and Deployment Kinematics and Dynamics (Chapter 6). Repeating the

  11. A random walk evolution model of wireless sensor networks and virus spreading

    International Nuclear Information System (INIS)

    Wang Ya-Qi; Yang Xiao-Yuan

    2013-01-01

    In this paper, considering both cluster heads and sensor nodes, we propose a novel evolving a network model based on a random walk to study the fault tolerance decrease of wireless sensor networks (WSNs) due to node failure, and discuss the spreading dynamic behavior of viruses in the evolution model. A theoretical analysis shows that the WSN generated by such an evolution model not only has a strong fault tolerance, but also can dynamically balance the energy loss of the entire network. It is also found that although the increase of the density of cluster heads in the network reduces the network efficiency, it can effectively inhibit the spread of viruses. In addition, the heterogeneity of the network improves the network efficiency and enhances the virus prevalence. We confirm all the theoretical results with sufficient numerical simulations. (general)

  12. Harvesting Entropy for Random Number Generation for Internet of Things Constrained Devices Using On-Board Sensors

    Directory of Open Access Journals (Sweden)

    Marcin Piotr Pawlowski

    2015-10-01

    Full Text Available Entropy in computer security is associated with the unpredictability of a source of randomness. The random source with high entropy tends to achieve a uniform distribution of random values. Random number generators are one of the most important building blocks of cryptosystems. In constrained devices of the Internet of Things ecosystem, high entropy random number generators are hard to achieve due to hardware limitations. For the purpose of the random number generation in constrained devices, this work proposes a solution based on the least-significant bits concatenation entropy harvesting method. As a potential source of entropy, on-board integrated sensors (i.e., temperature, humidity and two different light sensors have been analyzed. Additionally, the costs (i.e., time and memory consumption of the presented approach have been measured. The results obtained from the proposed method with statistical fine tuning achieved a Shannon entropy of around 7.9 bits per byte of data for temperature and humidity sensors. The results showed that sensor-based random number generators are a valuable source of entropy with very small RAM and Flash memory requirements for constrained devices of the Internet of Things.

  13. Harvesting Entropy for Random Number Generation for Internet of Things Constrained Devices Using On-Board Sensors

    Science.gov (United States)

    Pawlowski, Marcin Piotr; Jara, Antonio; Ogorzalek, Maciej

    2015-01-01

    Entropy in computer security is associated with the unpredictability of a source of randomness. The random source with high entropy tends to achieve a uniform distribution of random values. Random number generators are one of the most important building blocks of cryptosystems. In constrained devices of the Internet of Things ecosystem, high entropy random number generators are hard to achieve due to hardware limitations. For the purpose of the random number generation in constrained devices, this work proposes a solution based on the least-significant bits concatenation entropy harvesting method. As a potential source of entropy, on-board integrated sensors (i.e., temperature, humidity and two different light sensors) have been analyzed. Additionally, the costs (i.e., time and memory consumption) of the presented approach have been measured. The results obtained from the proposed method with statistical fine tuning achieved a Shannon entropy of around 7.9 bits per byte of data for temperature and humidity sensors. The results showed that sensor-based random number generators are a valuable source of entropy with very small RAM and Flash memory requirements for constrained devices of the Internet of Things. PMID:26506357

  14. Harvesting entropy for random number generation for internet of things constrained devices using on-board sensors.

    Science.gov (United States)

    Pawlowski, Marcin Piotr; Jara, Antonio; Ogorzalek, Maciej

    2015-10-22

    Entropy in computer security is associated with the unpredictability of a source of randomness. The random source with high entropy tends to achieve a uniform distribution of random values. Random number generators are one of the most important building blocks of cryptosystems. In constrained devices of the Internet of Things ecosystem, high entropy random number generators are hard to achieve due to hardware limitations. For the purpose of the random number generation in constrained devices, this work proposes a solution based on the least-significant bits concatenation entropy harvesting method. As a potential source of entropy, on-board integrated sensors (i.e., temperature, humidity and two different light sensors) have been analyzed. Additionally, the costs (i.e., time and memory consumption) of the presented approach have been measured. The results obtained from the proposed method with statistical fine tuning achieved a Shannon entropy of around 7.9 bits per byte of data for temperature and humidity sensors. The results showed that sensor-based random number generators are a valuable source of entropy with very small RAM and Flash memory requirements for constrained devices of the Internet of Things.

  15. New distributed fusion filtering algorithm based on covariances over sensor networks with random packet dropouts

    Science.gov (United States)

    Caballero-Águila, R.; Hermoso-Carazo, A.; Linares-Pérez, J.

    2017-07-01

    This paper studies the distributed fusion estimation problem from multisensor measured outputs perturbed by correlated noises and uncertainties modelled by random parameter matrices. Each sensor transmits its outputs to a local processor over a packet-erasure channel and, consequently, random losses may occur during transmission. Different white sequences of Bernoulli variables are introduced to model the transmission losses. For the estimation, each lost output is replaced by its estimator based on the information received previously, and only the covariances of the processes involved are used, without requiring the signal evolution model. First, a recursive algorithm for the local least-squares filters is derived by using an innovation approach. Then, the cross-correlation matrices between any two local filters is obtained. Finally, the distributed fusion filter weighted by matrices is obtained from the local filters by applying the least-squares criterion. The performance of the estimators and the influence of both sensor uncertainties and transmission losses on the estimation accuracy are analysed in a numerical example.

  16. Fault-tolerant topology in the wireless sensor networks for energy depletion and random failure

    International Nuclear Information System (INIS)

    Liu Bin; Dong Ming-Ru; Yin Rong-Rong; Yin Wen-Xiao

    2014-01-01

    Nodes in the wireless sensor networks (WSNs) are prone to failure due to energy depletion and poor environment, which could have a negative impact on the normal operation of the network. In order to solve this problem, in this paper, we build a fault-tolerant topology which can effectively tolerate energy depletion and random failure. Firstly, a comprehensive failure model about energy depletion and random failure is established. Then an improved evolution model is presented to generate a fault-tolerant topology, and the degree distribution of the topology can be adjusted. Finally, the relation between the degree distribution and the topological fault tolerance is analyzed, and the optimal value of evolution model parameter is obtained. Then the target fault-tolerant topology which can effectively tolerate energy depletion and random failure is obtained. The performances of the new fault tolerant topology are verified by simulation experiments. The results show that the new fault tolerant topology effectively prolongs the network lifetime and has strong fault tolerance. (general)

  17. Modeling random telegraph signal noise in CMOS image sensor under low light based on binomial distribution

    International Nuclear Information System (INIS)

    Zhang Yu; Wang Guangyi; Lu Xinmiao; Hu Yongcai; Xu Jiangtao

    2016-01-01

    The random telegraph signal noise in the pixel source follower MOSFET is the principle component of the noise in the CMOS image sensor under low light. In this paper, the physical and statistical model of the random telegraph signal noise in the pixel source follower based on the binomial distribution is set up. The number of electrons captured or released by the oxide traps in the unit time is described as the random variables which obey the binomial distribution. As a result, the output states and the corresponding probabilities of the first and the second samples of the correlated double sampling circuit are acquired. The standard deviation of the output states after the correlated double sampling circuit can be obtained accordingly. In the simulation section, one hundred thousand samples of the source follower MOSFET have been simulated, and the simulation results show that the proposed model has the similar statistical characteristics with the existing models under the effect of the channel length and the density of the oxide trap. Moreover, the noise histogram of the proposed model has been evaluated at different environmental temperatures. (paper)

  18. PUFKEY: a high-security and high-throughput hardware true random number generator for sensor networks.

    Science.gov (United States)

    Li, Dongfang; Lu, Zhaojun; Zou, Xuecheng; Liu, Zhenglin

    2015-10-16

    Random number generators (RNG) play an important role in many sensor network systems and applications, such as those requiring secure and robust communications. In this paper, we develop a high-security and high-throughput hardware true random number generator, called PUFKEY, which consists of two kinds of physical unclonable function (PUF) elements. Combined with a conditioning algorithm, true random seeds are extracted from the noise on the start-up pattern of SRAM memories. These true random seeds contain full entropy. Then, the true random seeds are used as the input for a non-deterministic hardware RNG to generate a stream of true random bits with a throughput as high as 803 Mbps. The experimental results show that the bitstream generated by the proposed PUFKEY can pass all standard national institute of standards and technology (NIST) randomness tests and is resilient to a wide range of security attacks.

  19. PUFKEY: A High-Security and High-Throughput Hardware True Random Number Generator for Sensor Networks

    Directory of Open Access Journals (Sweden)

    Dongfang Li

    2015-10-01

    Full Text Available Random number generators (RNG play an important role in many sensor network systems and applications, such as those requiring secure and robust communications. In this paper, we develop a high-security and high-throughput hardware true random number generator, called PUFKEY, which consists of two kinds of physical unclonable function (PUF elements. Combined with a conditioning algorithm, true random seeds are extracted from the noise on the start-up pattern of SRAM memories. These true random seeds contain full entropy. Then, the true random seeds are used as the input for a non-deterministic hardware RNG to generate a stream of true random bits with a throughput as high as 803 Mbps. The experimental results show that the bitstream generated by the proposed PUFKEY can pass all standard national institute of standards and technology (NIST randomness tests and is resilient to a wide range of security attacks.

  20. Selecting Optimal Parameters of Random Linear Network Coding for Wireless Sensor Networks

    DEFF Research Database (Denmark)

    Heide, J; Zhang, Qi; Fitzek, F H P

    2013-01-01

    This work studies how to select optimal code parameters of Random Linear Network Coding (RLNC) in Wireless Sensor Networks (WSNs). With Rateless Deluge [1] the authors proposed to apply Network Coding (NC) for Over-the-Air Programming (OAP) in WSNs, and demonstrated that with NC a significant...... reduction in the number of transmitted packets can be achieved. However, NC introduces additional computations and potentially a non-negligible transmission overhead, both of which depend on the chosen coding parameters. Therefore it is necessary to consider the trade-off that these coding parameters...... present in order to obtain the lowest energy consumption per transmitted bit. This problem is analyzed and suitable coding parameters are determined for the popular Tmote Sky platform. Compared to the use of traditional RLNC, these parameters enable a reduction in the energy spent per bit which grows...

  1. Sign Language Recognition with the Kinect Sensor Based on Conditional Random Fields

    Directory of Open Access Journals (Sweden)

    Hee-Deok Yang

    2014-12-01

    Full Text Available Sign language is a visual language used by deaf people. One difficulty of sign language recognition is that sign instances of vary in both motion and shape in three-dimensional (3D space. In this research, we use 3D depth information from hand motions, generated from Microsoft’s Kinect sensor and apply a hierarchical conditional random field (CRF that recognizes hand signs from the hand motions. The proposed method uses a hierarchical CRF to detect candidate segments of signs using hand motions, and then a BoostMap embedding method to verify the hand shapes of the segmented signs. Experiments demonstrated that the proposed method could recognize signs from signed sentence data at a rate of 90.4%.

  2. Sensors

    CERN Document Server

    Pigorsch, Enrico

    1997-01-01

    This is the 5th edition of the Metra Martech Directory "EUROPEAN CENTRES OF EXPERTISE - SENSORS." The entries represent a survey of European sensors development. The new edition contains 425 detailed profiles of companies and research institutions in 22 countries. This is reflected in the diversity of sensors development programmes described, from sensors for physical parameters to biosensors and intelligent sensor systems. We do not claim that all European organisations developing sensors are included, but this is a good cross section from an invited list of participants. If you see gaps or omissions, or would like your organisation to be included, please send details. The data base invites the formation of effective joint ventures by identifying and providing access to specific areas in which organisations offer collaboration. This issue is recognised to be of great importance and most entrants include details of collaboration offered and sought. We hope the directory on Sensors will help you to find the ri...

  3. Sensors

    Energy Technology Data Exchange (ETDEWEB)

    Jensen, H. [PBI-Dansensor A/S (Denmark); Toft Soerensen, O. [Risoe National Lab., Materials Research Dept. (Denmark)

    1999-10-01

    A new type of ceramic oxygen sensors based on semiconducting oxides was developed in this project. The advantage of these sensors compared to standard ZrO{sub 2} sensors is that they do not require a reference gas and that they can be produced in small sizes. The sensor design and the techniques developed for production of these sensors are judged suitable by the participating industry for a niche production of a new generation of oxygen sensors. Materials research on new oxygen ion conducting conductors both for applications in oxygen sensors and in fuel was also performed in this project and finally a new process was developed for fabrication of ceramic tubes by dip-coating. (EHS)

  4. Assessment of Antarctic moss health from multi-sensor UAS imagery with Random Forest Modelling

    Science.gov (United States)

    Turner, Darren; Lucieer, Arko; Malenovský, Zbyněk; King, Diana; Robinson, Sharon A.

    2018-06-01

    Moss beds are one of very few terrestrial vegetation types that can be found on the Antarctic continent and as such mapping their extent and monitoring their health is important to environmental managers. Across Antarctica, moss beds are experiencing changes in health as their environment changes. As Antarctic moss beds are spatially fragmented with relatively small extent they require very high resolution remotely sensed imagery to monitor their distribution and dynamics. This study demonstrates that multi-sensor imagery collected by an Unmanned Aircraft System (UAS) provides a novel data source for assessment of moss health. In this study, we train a Random Forest Regression Model (RFM) with long-term field quadrats at a study site in the Windmill Islands, East Antarctica and apply it to UAS RGB and 6-band multispectral imagery, derived vegetation indices, 3D topographic data, and thermal imagery to predict moss health. Our results suggest that moss health, expressed as a percentage between 0 and 100% healthy, can be estimated with a root mean squared error (RMSE) between 7 and 12%. The RFM also quantifies the importance of input variables for moss health estimation showing the multispectral sensor data was important for accurate health prediction, such information being essential for planning future field investigations. The RFM was applied to the entire moss bed, providing an extrapolation of the health assessment across a larger spatial area. With further validation the resulting maps could be used for change detection of moss health across multiple sites and seasons.

  5. Deployment Repeatability

    Science.gov (United States)

    2016-08-31

    large cohort of trials to spot unusual cases. However, deployment repeatability is inherently a nonlinear phenomenon, which makes modeling difficult...and GEMS tip position were both tracked during ground testing by a laser target tracking system. Earlier SAILMAST testing in 2005 [8] used...recalls the strategy used by SRTM, where a constellation of lights was installed at the tip of the boom and a modified star tracker was used to track tip

  6. A Tabu Search WSN Deployment Method for Monitoring Geographically Irregular Distributed Events

    Directory of Open Access Journals (Sweden)

    2009-03-01

    Full Text Available In this paper, we address the Wireless Sensor Network (WSN deployment issue. We assume that the observed area is characterized by the geographical irregularity of the sensed events. Formally, we consider that each point in the deployment area is associated a differentiated detection probability threshold, which must be satisfied by our deployment method. Our resulting WSN deployment problem is formulated as a Multi-Objectives Optimization problem, which seeks to reduce the gap between the generated events detection probabilities and the required thresholds while minimizing the number of deployed sensors. To overcome the computational complexity of an exact resolution, we propose an original pseudo-random approach based on the Tabu Search heuristic. Simulations show that our proposal achieves better performances than several other approaches proposed in the literature. In the last part of this paper, we generalize the deployment problem by including the wireless communication network connectivity constraint. Thus, we extend our proposal to ensure that the resulting WSN topology is connected even if a sensor communication range takes small values.

  7. A Tabu Search WSN Deployment Method for Monitoring Geographically Irregular Distributed Events.

    Science.gov (United States)

    Aitsaadi, Nadjib; Achir, Nadjib; Boussetta, Khaled; Pujolle, Guy

    2009-01-01

    In this paper, we address the Wireless Sensor Network (WSN) deployment issue. We assume that the observed area is characterized by the geographical irregularity of the sensed events. Formally, we consider that each point in the deployment area is associated a differentiated detection probability threshold, which must be satisfied by our deployment method. Our resulting WSN deployment problem is formulated as a Multi-Objectives Optimization problem, which seeks to reduce the gap between the generated events detection probabilities and the required thresholds while minimizing the number of deployed sensors. To overcome the computational complexity of an exact resolution, we propose an original pseudo-random approach based on the Tabu Search heuristic. Simulations show that our proposal achieves better performances than several other approaches proposed in the literature. In the last part of this paper, we generalize the deployment problem by including the wireless communication network connectivity constraint. Thus, we extend our proposal to ensure that the resulting WSN topology is connected even if a sensor communication range takes small values.

  8. Received signal strength in large-scale wireless relay sensor network: a stochastic ray approach

    NARCIS (Netherlands)

    Hu, L.; Chen, Y.; Scanlon, W.G.

    2011-01-01

    The authors consider a point percolation lattice representation of a large-scale wireless relay sensor network (WRSN) deployed in a cluttered environment. Each relay sensor corresponds to a grid point in the random lattice and the signal sent by the source is modelled as an ensemble of photons that

  9. AWARE: Platform for Autonomous self-deploying and operation of Wireless sensor-actuator networks cooperating with unmanned AeRial vehiclEs

    NARCIS (Netherlands)

    Ollero, Anibal; Bernard, Markus; La Civita, Marco; van Hoesel, L.F.W.; Marron, Pedro J.; Lepley, Jason; de Andres, Eduardo

    This paper presents the AWARE platform that seeks to enable the cooperation of autonomous aerial vehicles with ground wireless sensor-actuator networks comprising both static and mobile nodes carried by vehicles or people. Particularly, the paper presents the middleware, the wireless sensor network,

  10. Dynamic Sensor Networks

    National Research Council Canada - National Science Library

    Schott, Brian

    2004-01-01

    ...: Declarative Languages and Execution Environment includes topographical soldier interface and a sensor network simulation environment for algorithm development, deployment planning, and operational support. Finally, Task 3...

  11. Sensor

    OpenAIRE

    Gleeson, Helen; Dierking, Ingo; Grieve, Bruce; Woodyatt, Christopher; Brimicombe, Paul

    2015-01-01

    An electrical temperature sensor (10) comprises a liquid crystalline material (12). First and second electrically conductive contacts (14), (16), having a spaced relationship there between, contact the liquid crystalline material (12). An electric property measuring device is electrically connected to the first and second contacts (14), (16) and is arranged to measure an electric property of the liquid crystalline material (12). The liquid crystalline material (12) has a transition temperatur...

  12. SENSE IT: Teaching STEM Principles to Middle and High School Students through the Design, Construction and Deployment of Water Quality Sensors

    Science.gov (United States)

    Hotaling, Liesl; Lowes, Susan; Stolkin, Rustam; Lin, Peiyi; Bonner, James; Kirkey, William; Ojo, Temitope

    2012-01-01

    This paper describes the structure and impact of an NSF-funded ITEST project designed to enrich science, technology, engineering, and mathematics (STEM) education using educational modules that teach students to construct, program, and test a series of sensors used to monitor water quality. During the two years of the SENSE IT project, over 30…

  13. Hole Detection for Quantifying Connectivity in Wireless Sensor Networks: A Survey

    OpenAIRE

    Pearl Antil; Amita Malik

    2014-01-01

    Owing to random deployment, environmental factors, dynamic topology, and external attacks, emergence of holes in wireless sensor networks is inescapable. Hole is an area in sensor network around which sensors cease to sense or communicate due to drainage of battery or any fault, either temporary or permanent. Holes impair sensing and communication functions of network; thus their identification is a major concern. This paper discusses different types of holes and significance of hole detectio...

  14. Performance Analysis of Receive Diversity in Wireless Sensor Networks over GBSBE Models

    OpenAIRE

    Goel, Shivali; Abawajy, Jemal H.; Kim, Tai-hoon

    2010-01-01

    Wireless sensor networks have attracted a lot of attention recently. In this paper, we develop a channel model based on the elliptical model for multipath components involving randomly placed scatterers in the scattering region with sensors deployed on a field. We verify that in a sensor network, the use of receive diversity techniques improves the performance of the system. Extensive performance analysis of the system is carried out for both single and multiple antennas with the applied rece...

  15. Target Coverage in Wireless Sensor Networks with Probabilistic Sensors

    Science.gov (United States)

    Shan, Anxing; Xu, Xianghua; Cheng, Zongmao

    2016-01-01

    Sensing coverage is a fundamental problem in wireless sensor networks (WSNs), which has attracted considerable attention. Conventional research on this topic focuses on the 0/1 coverage model, which is only a coarse approximation to the practical sensing model. In this paper, we study the target coverage problem, where the objective is to find the least number of sensor nodes in randomly-deployed WSNs based on the probabilistic sensing model. We analyze the joint detection probability of target with multiple sensors. Based on the theoretical analysis of the detection probability, we formulate the minimum ϵ-detection coverage problem. We prove that the minimum ϵ-detection coverage problem is NP-hard and present an approximation algorithm called the Probabilistic Sensor Coverage Algorithm (PSCA) with provable approximation ratios. To evaluate our design, we analyze the performance of PSCA theoretically and also perform extensive simulations to demonstrate the effectiveness of our proposed algorithm. PMID:27618902

  16. Effect of drain current on appearance probability and amplitude of random telegraph noise in low-noise CMOS image sensors

    Science.gov (United States)

    Ichino, Shinya; Mawaki, Takezo; Teramoto, Akinobu; Kuroda, Rihito; Park, Hyeonwoo; Wakashima, Shunichi; Goto, Tetsuya; Suwa, Tomoyuki; Sugawa, Shigetoshi

    2018-04-01

    Random telegraph noise (RTN), which occurs in in-pixel source follower (SF) transistors, has become one of the most critical problems in high-sensitivity CMOS image sensors (CIS) because it is a limiting factor of dark random noise. In this paper, the behaviors of RTN toward changes in SF drain current conditions were analyzed using a low-noise array test circuit measurement system with a floor noise of 35 µV rms. In addition to statistical analysis by measuring a large number of transistors (18048 transistors), we also analyzed the behaviors of RTN parameters such as amplitude and time constants in the individual transistors. It is demonstrated that the appearance probability of RTN becomes small under a small drain current condition, although large-amplitude RTN tends to appear in a very small number of cells.

  17. Quality function deployment

    International Nuclear Information System (INIS)

    1981-10-01

    This book indicates quality function deployment with quality and deployment of quality function, process and prospect of quality function deployment and development, product process and conception of quality table, deployment of quality demand, design of quality table and application of concurrent multi design, progress design and quality development, main safe part and management of important function part, quality development and deployment of method of construction, quality deployment and economics, total system of quality function deployment and task of quality function deployment in the present and future.

  18. HIGH: A Hexagon-based Intelligent Grouping Approach in Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    FAN, C.-S.

    2016-02-01

    Full Text Available In a random deployment or uniform deployment strategy, sensor nodes are scattered randomly or uniformly in the sensing field, respectively. Hence, the coverage ratio cannot be guaranteed. The coverage ratio of uniform deployment, in general, is larger than that of the random deployment strategy. However, a random deployment or uniform deployment strategy may cause unbalanced traffic pattern in wireless sensor networks (WSNs. Therefore, cluster heads (CHs around the sink have larger loads than those farther away from the sink. That is, CHs close to the sink exhaust their energy earlier. In order to overcome the above problem, we propose a Hexagon-based Intelligent Grouping approacH in WSNs (called HIGH. The coverage, energy consumption and data routing issues are well investigated and taken into consideration in the proposed HIGH scheme. The simulation results validate our theoretical analysis and show that the proposed HIGH scheme achieves a satisfactory coverage ratio, balances the energy consumption among sensor nodes, and extends network lifetime significantly.

  19. Random Forest-Based Recognition of Isolated Sign Language Subwords Using Data from Accelerometers and Surface Electromyographic Sensors.

    Science.gov (United States)

    Su, Ruiliang; Chen, Xiang; Cao, Shuai; Zhang, Xu

    2016-01-14

    Sign language recognition (SLR) has been widely used for communication amongst the hearing-impaired and non-verbal community. This paper proposes an accurate and robust SLR framework using an improved decision tree as the base classifier of random forests. This framework was used to recognize Chinese sign language subwords using recordings from a pair of portable devices worn on both arms consisting of accelerometers (ACC) and surface electromyography (sEMG) sensors. The experimental results demonstrated the validity of the proposed random forest-based method for recognition of Chinese sign language (CSL) subwords. With the proposed method, 98.25% average accuracy was obtained for the classification of a list of 121 frequently used CSL subwords. Moreover, the random forests method demonstrated a superior performance in resisting the impact of bad training samples. When the proportion of bad samples in the training set reached 50%, the recognition error rate of the random forest-based method was only 10.67%, while that of a single decision tree adopted in our previous work was almost 27.5%. Our study offers a practical way of realizing a robust and wearable EMG-ACC-based SLR systems.

  20. Analysis of using interpulse intervals to generate 128-bit biometric random binary sequences for securing wireless body sensor networks.

    Science.gov (United States)

    Zhang, Guang-He; Poon, Carmen C Y; Zhang, Yuan-Ting

    2012-01-01

    Wireless body sensor network (WBSN), a key building block for m-Health, demands extremely stringent resource constraints and thus lightweight security methods are preferred. To minimize resource consumption, utilizing information already available to a WBSN, particularly common to different sensor nodes of a WBSN, for security purposes becomes an attractive solution. In this paper, we tested the randomness and distinctiveness of the 128-bit biometric binary sequences (BSs) generated from interpulse intervals (IPIs) of 20 healthy subjects as well as 30 patients suffered from myocardial infarction and 34 subjects with other cardiovascular diseases. The encoding time of a biometric BS on a WBSN node is on average 23 ms and memory occupation is 204 bytes for any given IPI sequence. The results from five U.S. National Institute of Standards and Technology statistical tests suggest that random biometric BSs can be generated from both healthy subjects and cardiovascular patients and can potentially be used as authentication identifiers for securing WBSNs. Ultimately, it is preferred that these biometric BSs can be used as encryption keys such that key distribution over the WBSN can be avoided.

  1. Random Forest Classification of Wetland Landcovers from Multi-Sensor Data in the Arid Region of Xinjiang, China

    Directory of Open Access Journals (Sweden)

    Shaohong Tian

    2016-11-01

    Full Text Available The wetland classification from remotely sensed data is usually difficult due to the extensive seasonal vegetation dynamics and hydrological fluctuation. This study presents a random forest classification approach for the retrieval of the wetland landcover in the arid regions by fusing the Pléiade-1B data with multi-date Landsat-8 data. The segmentation of the Pléiade-1B multispectral image data was performed based on an object-oriented approach, and the geometric and spectral features were extracted for the segmented image objects. The normalized difference vegetation index (NDVI series data were also calculated from the multi-date Landsat-8 data, reflecting vegetation phenological changes in its growth cycle. The feature set extracted from the two sensors data was optimized and employed to create the random forest model for the classification of the wetland landcovers in the Ertix River in northern Xinjiang, China. Comparison with other classification methods such as support vector machine and artificial neural network classifiers indicates that the random forest classifier can achieve accurate classification with an overall accuracy of 93% and the Kappa coefficient of 0.92. The classification accuracy of the farming lands and water bodies that have distinct boundaries with the surrounding land covers was improved 5%–10% by making use of the property of geometric shapes. To remove the difficulty in the classification that was caused by the similar spectral features of the vegetation covers, the phenological difference and the textural information of co-occurrence gray matrix were incorporated into the classification, and the main wetland vegetation covers in the study area were derived from the two sensors data. The inclusion of phenological information in the classification enables the classification errors being reduced down, and the overall accuracy was improved approximately 10%. The results show that the proposed random forest

  2. Conditional Random Fields versus Hidden Markov Models for activity recognition in temporal sensor data

    NARCIS (Netherlands)

    van Kasteren, T.L.M.; Noulas, A.K.; Kröse, B.J.A.; Smit, G.J.M.; Epema, D.H.J.; Lew, M.S.

    2008-01-01

    Conditional Random Fields are a discriminative probabilistic model which recently gained popularity in applications that require modeling nonindependent observation sequences. In this work, we present the basic advantages of this model over generative models and argue about its suitability in the

  3. A Method of Reducing Random Drift in the Combined Signal of an Array of Inertial Sensors

    Science.gov (United States)

    2015-09-30

    stability of the collective output, Bayard et al, US Patent 6,882,964. The prior art methods rely upon the use of Kalman filtering and averaging...including scale-factor errors, quantization effects, temperature effects, random drift, and additive noise. A comprehensive account of all of these

  4. Non-traditional Infrasound Deployment

    Science.gov (United States)

    McKenna, M. H.; McComas, S.; Simpson, C. P.; Diaz-Alvarez, H.; Costley, R. D.; Hayward, C.; Golden, P.; Endress, A.

    2017-12-01

    Historically, infrasound arrays have been deployed in rural environments where anthropological noise sources are limited. As interest in monitoring low energy sources at local distances grows in the infrasound community, it will be vital to understand how to monitor infrasound sources in an urban environment. Arrays deployed in urban centers have to overcome the decreased signal-to-noise ratio and reduced amount of real estate available to deploy an array. To advance the understanding of monitoring infrasound sources in urban environments, local and regional infrasound arrays were deployed on building rooftops on the campus at Southern Methodist University (SMU), and data were collected for one seasonal cycle. The data were evaluated for structural source signals (continuous-wave packets), and when a signal was identified, the back azimuth to the source was determined through frequency-wavenumber analysis. This information was used to identify hypothesized structural sources; these sources were verified through direct measurement and dynamic structural analysis modeling. In addition to the rooftop arrays, a camouflaged infrasound sensor was installed on the SMU campus and evaluated to determine its effectiveness for wind noise reduction. Permission to publish was granted by Director, Geotechnical and Structures Laboratory.

  5. Event-Triggered Fault Estimation for Stochastic Systems over Multi-Hop Relay Networks with Randomly Occurring Sensor Nonlinearities and Packet Dropouts.

    Science.gov (United States)

    Li, Yunji; Peng, Li

    2018-02-28

    Wireless sensors have many new applications where remote estimation is essential. Considering that a remote estimator is located far away from the process and the wireless transmission distance of sensor nodes is limited, sensor nodes always forward data packets to the remote estimator through a series of relays over a multi-hop link. In this paper, we consider a network with sensor nodes and relay nodes where the relay nodes can forward the estimated values to the remote estimator. An event-triggered remote estimator of state and fault with the corresponding data-forwarding scheme is investigated for stochastic systems subject to both randomly occurring nonlinearity and randomly occurring packet dropouts governed by Bernoulli-distributed sequences to achieve a trade-off between estimation accuracy and energy consumption. Recursive Riccati-like matrix equations are established to calculate the estimator gain to minimize an upper bound of the estimator error covariance. Subsequently, a sufficient condition and data-forwarding scheme are presented under which the error covariance is mean-square bounded in the multi-hop links with random packet dropouts. Furthermore, implementation issues of the theoretical results are discussed where a new data-forwarding communication protocol is designed. Finally, the effectiveness of the proposed algorithms and communication protocol are extensively evaluated using an experimental platform that was established for performance evaluation with a sensor and two relay nodes.

  6. Sensor-augmented pump therapy lowers HbA(1c) in suboptimally controlled Type 1 diabetes; a randomized controlled trial

    NARCIS (Netherlands)

    Hermanides, J.; Nørgaard, K.; Bruttomesso, D.; Mathieu, C.; Frid, A.; Dayan, C. M.; Diem, P.; Fermon, C.; Wentholt, I. M. E.; Hoekstra, J. B. L.; DeVries, J. H.

    2011-01-01

    To investigate the efficacy of sensor-augmented pump therapy vs. multiple daily injection therapy in patients with suboptimally controlled Type 1 diabetes. In this investigator-initiated multi-centre trial (the Eurythmics Trial) in eight outpatient centres in Europe, we randomized 83 patients with

  7. Solar sail deployment experiment

    OpenAIRE

    Shimose, Shigeru; 下瀬 滋

    2006-01-01

    Solar Sail move by receiving momentum of photons in sunlight. This paper presents results of some Spin-Stabilized Solar Sail deployment experiment. ISAS has successfully deployed, for the first time in the world, the polyimide Solar Sail taking advantage of centrifugal force in space. Based on this result, the new deployment mechanism is being developed which retracts the 50 m diameter sail.

  8. A Remotely Deployable Wind Sonic Anemometer

    Directory of Open Access Journals (Sweden)

    Muhammad Awais

    2017-12-01

    Full Text Available Communication and computing shape up base for explosion of Internet of Things (IoT era. Humans can efficiently control the devices around their environment as per requirements because of IoT, the communication between different devices brings more flexibility in surrounding. Useful data is also gathered from some of these devices to create Big Data; where, further analysis assist in making life easier by developing good business models corresponding to user needs, enhance scientific research, formulating weather prediction or monitoring systems and contributing in other relative fields as well. Thus, in this research a remotely deployable IoT enabled Wind Sonic Anemometer has been designed and deployed to calculate average wind speed, direction, and gust. The proposed design is remotely deployable, user-friendly, power efficient and cost-effective because of opted modules i.e., ultrasonic sensors, GSM module, and solar panel. The testbed was also deployed at the roof of Computer & Information Systems Engineering (CIS department, NED UET. Further, its calibration has been carried out by using long short-term memory (LSTM, a deep learning technique; where ground truth data has been gathered from mechanical wind speed sensor (NRG-40 H deployed at top of Industrial & Manufacturing (IM department of NED UET. The obtained results are satisfactory and the performance of designed sensor is also good under various weather conditions.

  9. Mastering Windows 7 Deployment

    CERN Document Server

    Finn, Aidan; van Surksum, Kenneth

    2011-01-01

    Get professional-level instruction on Windows 7 deployment tools Enterprise-level operating system deployment is challenging and requires knowledge of specific tools. It is expected that Windows 7 will be extensively deployed in businesses worldwide. This comprehensive Sybex guide provides thorough coverage of the Microsoft deployment tools that were specifically created for Windows 7, preparing system administrators, MIS professionals, and corporate programmers to tackle the task effectively.Companies worldwide are expected to deploy Windows 7 as their enterprise operating system; system admi

  10. Random three-dimensional jammed packings of elastic shells acting as force sensors

    Science.gov (United States)

    Jose, Jissy; van Blaaderen, Alfons; Imhof, Arnout

    2016-06-01

    In a jammed solid of granular particles, the applied stress is in-homogeneously distributed within the packing. A full experimental characterization requires measurement of all the interparticle forces, but so far such measurements are limited to a few systems in two and even fewer in three dimensions. Particles with the topology of (elastic) shells are good local force sensors as relatively large deformations of the shells result from relatively small forces. We recently introduced such fluorescent shells as a model granular system in which force distributions can be determined in three dimensions using confocal microscopy and quantitative image analysis. An interesting aspect about these shells that differentiates them from other soft deformable particles is their buckling behavior at higher compression. This leads to deformations that do not conserve the inner volume of the particle. Here we use this system to accurately measure the contact forces in a three-dimensional packing of shells subjected to a static anisotropic compression and to shear. At small deformations forces are linear, however, for a buckled contact, the restoring force is related to the amount of deformation by a square root law, as follows from the theory of elasticity of shells. Near the unjamming-jamming transition (point J ), we found the probability distribution of the interparticle forces P (f ) to decay nearly exponentially at large forces, with little evidence of long-range force chains in the packings. As the packing density is increased, the tail of the distribution was found to crossover to a Gaussian, in line with other experimental and simulation studies. Under a small shear strain, up to 0.216, applied at an extremely low shear rate, we observed a shear-induced anisotropy in both the pair correlation function and contact force network; however, no appreciable change was seen in the number of contacts per particle.

  11. Interactive Sensor-Based Balance Training in Older Cancer Patients with Chemotherapy-Induced Peripheral Neuropathy: A Randomized Controlled Trial.

    Science.gov (United States)

    Schwenk, Michael; Grewal, Gurtej S; Holloway, Dustin; Muchna, Amy; Garland, Linda; Najafi, Bijan

    2016-01-01

    Cancer patients with chemotherapy-induced peripheral neuropathy (CIPN) have deficits in sensory and motor skills leading to inappropriate proprioceptive feedback, impaired postural control, and fall risk. Balance training programs specifically developed for CIPN patients are lacking. This pilot study investigated the effect of an interactive motor adaptation balance training program based on wearable sensors for improving balance in older cancer patients with CIPN. Twenty-two patients (age: 70.3 ± 8.7 years) with objectively confirmed CIPN [vibration perception threshold (VPT) >25 V] were randomized to either an intervention (IG) or a control (CG) group. The IG received interactive game-based balance training including repetitive weight shifting and virtual obstacle crossing tasks. Wearable sensors provided real-time visual/auditory feedback from the lower limb trajectory and allowed the perception of motor errors during each motor action. The CG received no exercise intervention and continued their normal activity. Outcome measures were changes in sway of ankle, hip, and center of mass (CoM) in both mediolateral and anteroposterior (AP) directions during 30-second balance tests with increasing task difficulty [i.e. standing in feet-closed position with eyes open (EO) and eyes closed (EC), and in semi-tandem position with EO] at baseline and after the intervention. Additionally, gait performance (speed, variability) and fear of falling [Falls Efficacy Scale-International (FES-I)] were measured. Training was safe despite the participants' impaired health status, great severity of CIPN (VPT 49.6 ± 26.7 V), and great fear of falling (FES-I score 31.37 ± 11.20). After the intervention, sway of hip, ankle, and CoM was significantly reduced in the IG compared to the CG while standing in feet-closed position with EO (p = 0.010-0.022, except AP CoM sway) and in semi-tandem position (p = 0.008-0.035, except ankle sway). No significant effects were found for balance with

  12. A preliminary randomized controlled trial of contingency management for alcohol use reduction using a transdermal alcohol sensor.

    Science.gov (United States)

    Barnett, Nancy P; Celio, Mark A; Tidey, Jennifer W; Murphy, James G; Colby, Suzanne M; Swift, Robert M

    2017-06-01

    We tested the efficacy of daily contingent reinforcement for reducing alcohol use compared with (yoked) non-contingent reinforcement (NR) using a transdermal alcohol sensor to detect alcohol use. Pilot randomized controlled design with 1 baseline week, 3 intervention weeks and 1-month follow-up. New England, USA. Heavy drinking adults (46.7% female) not seeking treatment were randomized to (1) an escalating schedule of cash reinforcement (CR; n = 15) for days on which alcohol was neither reported nor detected or (2) yoked NR (n = 15). Reinforcement for CR participants started at $5 and increased $2 every subsequent day on which alcohol was not detected or reported, to a maximum of $17. Participants received no reinforcement for days on which alcohol use was detected or reported, and the reinforcer value was re-set to $5 the day after a drinking day. NR participants were yoked to the daily reinforcer value of an individual in the CR condition, in order of enrollment. Paired participants in CR and NR therefore received the same amount of money, but the amount for the NR participant was not behavior-related. The primary outcome was percentage of days without sensor-detected drinking. Secondary outcomes were number of consecutive days with no detected drinking, peak transdermal alcohol concentration (TAC), self-reported drinks per week and drinking below NIH low-risk guidelines. Controlling for baseline, CR had a higher percentage of days with no drinking detected (54.3%) than NR (31.2%) during intervention weeks [P = 0.05, Cohen's d = 0.74; 95% confidence interval (CI) = 0.007-1.47]. The longest period of consecutive days with no drinking detected was 8.0 for CR versus 2.9 for NR (P = 0.03, d = 0.85; 95% CI = 0.08-1.61). Peak TAC during intervention showed a non-significant group difference (P = 0.20; d = 0.48; 95% CI = 0.00-1.18); a similar result was found for drinks per week (P = 0.12; d = 0.59; 95% CI = 0.00-1.30). Four times more

  13. Localization with a mobile beacon in underwater acoustic sensor networks.

    Science.gov (United States)

    Lee, Sangho; Kim, Kiseon

    2012-01-01

    Localization is one of the most important issues associated with underwater acoustic sensor networks, especially when sensor nodes are randomly deployed. Given that it is difficult to deploy beacon nodes at predetermined locations, localization schemes with a mobile beacon on the sea surface or along the planned path are inherently convenient, accurate, and energy-efficient. In this paper, we propose a new range-free Localization with a Mobile Beacon (LoMoB). The mobile beacon periodically broadcasts a beacon message containing its location. Sensor nodes are individually localized by passively receiving the beacon messages without inter-node communications. For location estimation, a set of potential locations are obtained as candidates for a node's location and then the node's location is determined through the weighted mean of all the potential locations with the weights computed based on residuals.

  14. Localization with a Mobile Beacon in Underwater Acoustic Sensor Networks

    Directory of Open Access Journals (Sweden)

    Sangho Lee

    2012-04-01

    Full Text Available Localization is one of the most important issues associated with underwater acoustic sensor networks, especially when sensor nodes are randomly deployed. Given that it is difficult to deploy beacon nodes at predetermined locations, localization schemes with a mobile beacon on the sea surface or along the planned path are inherently convenient, accurate, and energy-efficient. In this paper, we propose a new range-free Localization with a Mobile Beacon (LoMoB. The mobile beacon periodically broadcasts a beacon message containing its location. Sensor nodes are individually localized by passively receiving the beacon messages without inter-node communications. For location estimation, a set of potential locations are obtained as candidates for a node’s location and then the node’s location is determined through the weighted mean of all the potential locations with the weights computed based on residuals.

  15. Tether Deployer And Brake

    Science.gov (United States)

    Carroll, Joseph A.; Alexander, Charles M.

    1993-01-01

    Design concept promises speed, control, and reliability. Scheme for deploying tether provides for fast, free, and snagless payout and fast, dependable braking. Developed for small, expendable tethers in outer space, scheme also useful in laying transoceanic cables, deploying guidance wires to torpedoes and missiles, paying out rescue lines from ship to ship via rockets, deploying antenna wires, releasing communication and power cables to sonobuoys and expendable bathythermographs, and in reeling out lines from fishing rods.

  16. RSOI: Force Deployment Bottleneck

    National Research Council Canada - National Science Library

    D'Amato, Mark

    1998-01-01

    This study uses The Theory Of Constraints (TOC) management methodology and recent military missions to show that RSOI operations are generally the limiting constraint to force deployment operations...

  17. Center for Deployment Psychology

    Data.gov (United States)

    Federal Laboratory Consortium — The Center for Deployment Psychology was developed to promote the education of psychologists and other behavioral health specialists about issues pertaining to the...

  18. Deployment Health Surveillance

    National Research Council Canada - National Science Library

    DeNicola, Anthony D

    2004-01-01

    .... Gulf War health questions have resulted in controversy over potentially hazardous exposures during the deployment, the possibility of adverse affects from preventive health measures, and the role...

  19. Deployment Strategies and Clustering Protocols Efficiency

    Directory of Open Access Journals (Sweden)

    Chérif Diallo

    2017-06-01

    Full Text Available Wireless sensor networks face significant design challenges due to limited computing and storage capacities and, most importantly, dependence on limited battery power. Energy is a critical resource and is often an important issue to the deployment of sensor applications that claim to be omnipresent in the world of future. Thus optimizing the deployment of sensors becomes a major constraint in the design and implementation of a WSN in order to ensure better network operations. In wireless networking, clustering techniques add scalability, reduce the computation complexity of routing protocols, allow data aggregation and then enhance the network performance. The well-known MaxMin clustering algorithm was previously generalized, corrected and validated. Then, in a previous work we have improved MaxMin by proposing a Single- node Cluster Reduction (SNCR mechanism which eliminates single-node clusters and then improve energy efficiency. In this paper, we show that MaxMin, because of its original pathological case, does not support the grid deployment topology, which is frequently used in WSN architectures. The unreliability feature of the wireless links could have negative impacts on Link Quality Indicator (LQI based clustering protocols. So, in the second part of this paper we show how our distributed Link Quality based d- Clustering Protocol (LQI-DCP has good performance in both stable and high unreliable link environments. Finally, performance evaluation results also show that LQI-DCP fully supports the grid deployment topology and is more energy efficient than MaxMin.

  20. Modeling EERE Deployment Programs

    Energy Technology Data Exchange (ETDEWEB)

    Cort, K. A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Hostick, D. J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Belzer, D. B. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Livingston, O. V. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2007-11-01

    This report compiles information and conclusions gathered as part of the “Modeling EERE Deployment Programs” project. The purpose of the project was to identify and characterize the modeling of deployment programs within the EERE Technology Development (TD) programs, address possible improvements to the modeling process, and note gaps in knowledge in which future research is needed.

  1. Part 8. Deployment considerations

    International Nuclear Information System (INIS)

    Dance, K.D.; Chang, Y.I.; Daly, T.A.

    1980-01-01

    This report addresses considerations of fast breeder reactor development and deployment from a national perspective. Nations vary greatly in their expertise and interest relative to nuclear power, and hence a single set of steps to be taken by a nation in decision-making on breeder development and deployment cannot be presented. The approach taken in this report is to present discussions on key factors influencing the breeder development and deployment decisions, especially in non-breeder nations, by drawing upon historical perspectives of the Light Water Reactor for comparison

  2. Energy-aware scheduling of surveillance in wireless multimedia sensor networks.

    Science.gov (United States)

    Wang, Xue; Wang, Sheng; Ma, Junjie; Sun, Xinyao

    2010-01-01

    Wireless sensor networks involve a large number of sensor nodes with limited energy supply, which impacts the behavior of their application. In wireless multimedia sensor networks, sensor nodes are equipped with audio and visual information collection modules. Multimedia contents are ubiquitously retrieved in surveillance applications. To solve the energy problems during target surveillance with wireless multimedia sensor networks, an energy-aware sensor scheduling method is proposed in this paper. Sensor nodes which acquire acoustic signals are deployed randomly in the sensing fields. Target localization is based on the signal energy feature provided by multiple sensor nodes, employing particle swarm optimization (PSO). During the target surveillance procedure, sensor nodes are adaptively grouped in a totally distributed manner. Specially, the target motion information is extracted by a forecasting algorithm, which is based on the hidden Markov model (HMM). The forecasting results are utilized to awaken sensor node in the vicinity of future target position. According to the two properties, signal energy feature and residual energy, the sensor nodes decide whether to participate in target detection separately with a fuzzy control approach. Meanwhile, the local routing scheme of data transmission towards the observer is discussed. Experimental results demonstrate the efficiency of energy-aware scheduling of surveillance in wireless multimedia sensor network, where significant energy saving is achieved by the sensor awakening approach and data transmission paths are calculated with low computational complexity.

  3. Minimizing the Energy Consumption in ‎Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Mohammed Saad Talib

    2017-12-01

    Full Text Available Energy in Wireless Sensor networks (WSNs represents an essential factor in designing, controlling and operating the sensor networks. Minimizing the consumed energy in WSNs application is a crucial issue for the network effectiveness and efficiency in terms of lifetime, cost and operation. Number of algorithms and protocols were proposed and implemented to decrease the energy consumption. WSNs operate with battery powered sensors. Sensors batteries have not easily rechargeable even though having restricted power. Frequently the network failure occurs due to the sensors energy insufficiency. MAC protocols in WSNs achieved low duty-cycle by employing periodic sleep and wakeup. Predictive Wakeup MAC (PW-MAC protocol was made use of the asynchronous duty cycling. It reduces the consumption of the node energy by allowing the senders to predict the receiver′s wakeup times. The WSN must be applied in an efficient manner to utilize the sensor nodes and their energy to ensure efficient network throughput. Prediction of the WSN lifetime previously to its installation represents a significant concern. To ensure energy efficiency the sensors duty cycles must be adjusted appropriately to meet the network traffic demands. The energy consumed in each node due to its switching between the active and the idle states were also estimated. The sensors are assumed to be randomly deployed. This paper aims to improve the randomly deployed network lifetime by scheduling the effects of transmission, reception and sleep states on the sensor node energy consumption. Results for these states with many performance metrics were also studied and discussed

  4. Deployment Health Surveillance

    National Research Council Canada - National Science Library

    DeNicola, Anthony D

    2004-01-01

    ... of stress in causing chronic illness. The lack of comprehensive deployment health surveillance has made it difficult to determine possible causes of adverse health effects reported by Gulf War veterans...

  5. Modeling EERE deployment programs

    Energy Technology Data Exchange (ETDEWEB)

    Cort, K. A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Hostick, D. J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Belzer, D. B. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Livingston, O. V. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2007-11-01

    The purpose of the project was to identify and characterize the modeling of deployment programs within the EERE Technology Development (TD) programs, address possible improvements to the modeling process, and note gaps in knowledge for future research.

  6. RSOI: Force Deployment Bottleneck

    National Research Council Canada - National Science Library

    D'Amato, Mark

    1998-01-01

    .... This runs counter to the popular belief that strategic lift is the limiting constraint. The study begins by highlighting the genesis of the military's current force projection strategy and the resulting importance of rapid force deployments...

  7. Deployable Brake for Spacecraft

    Science.gov (United States)

    Rausch, J. R.; Maloney, J. W.

    1987-01-01

    Aerodynamic shield that could be opened and closed proposed. Report presents concepts for deployable aerodynamic brake. Brake used by spacecraft returning from high orbit to low orbit around Earth. Spacecraft makes grazing passes through atmosphere to slow down by drag of brake. Brake flexible shield made of woven metal or ceramic withstanding high temperatures created by air friction. Stored until needed, then deployed by set of struts.

  8. Coupled wave sensor technology

    International Nuclear Information System (INIS)

    Maki, M.C.

    1988-01-01

    Buried line guided radar sensors have been used successfully for a number of years to provide perimeter security for high value resources. This paper introduces a new complementary sensor advancement at Computing Devices termed 'coupled wave device technology' (CWD). It provides many of the inherent advantages of leakey cable sensors, such as terrain-following and the ability to discriminate between humans and small animals. It also is able to provide a high or wide detection zone, and allows the sensor to be mounted aerially and adjacent to a wall or fence. Several alternative sensors have been developed which include a single-line sensor, a dual-line hybrid sensor that combines the elements of ported coax and CWD technology, and a rapid-deployment portable sensor for temporary or mobile applications. A description of the technology, the sensors, and their characteristics is provided

  9. Impact of sensor detection limits on protecting water distribution systems from contamination events

    International Nuclear Information System (INIS)

    McKenna, Sean Andrew; Hart, David Blaine; Yarrington, Lane

    2006-01-01

    Real-time water quality sensors are becoming commonplace in water distribution systems. However, field deployable, contaminant-specific sensors are still in the development stage. As development proceeds, the necessary operating parameters of these sensors must be determined to protect consumers from accidental and malevolent contamination events. This objective can be quantified in several different ways including minimization of: the time necessary to detect a contamination event, the population exposed to contaminated water, the extent of the contamination within the network, and others. We examine the ability of a sensor set to meet these objectives as a function of both the detection limit of the sensors and the number of sensors in the network. A moderately sized distribution network is used as an example and different sized sets of randomly placed sensors are considered. For each combination of a certain number of sensors and a detection limit, the mean values of the different objectives across multiple random sensor placements are calculated. The tradeoff between the necessary detection limit in a sensor and the number of sensors is evaluated. Results show that for the example problem examined here, a sensor detection limit of 0.01 of the average source concentration is adequate for maximum protection. Detection of events is dependent on the detection limit of the sensors, but for those events that are detected, the values of the performance measures are not a function of the sensor detection limit. The results of replacing a single sensor in a network with a sensor having a much lower detection limit show that while this replacement can improve results, the majority of the additional events detected had performance measures of relatively low consequence.

  10. An analytic Study of the Key Factors In uencing the Design and Routing Techniques of a Wireless Sensor Network

    Directory of Open Access Journals (Sweden)

    Yogita Bahuguna

    2017-03-01

    Full Text Available A wireless sensor network contains various nodes having certain sensing, processing and communication capabilities. Actually they are multifunctional battery operated nodes called motes. These motes are small in size and battery constrained. They are operated by a power source. A wireless sensor network consists of a huge number of tiny sensor nodes which are deployed either randomly or according to some predefined distribution. The sensors nodes in a sensor network are cooperative among themselves having self-organizing ability. This ensures that a wireless network serves a wide variety of applications. Few of them are weather monitoring, health, security and military etc. As their applications are wide, this requires that sensors in a sensor network must play their role very efficiently. But, as discussed above, the sensor nodes have energy limitation. This limitation leads failure of nodes after certain round of communication. So, a sensor network suffers with sensors having energy limitations. Beside this, sensor nodes in a sensor network must fulfill connectivity and coverage requirements. In this paper, we have discussed various issues affecting the design of a wireless sensor network. This provides the readers various research issues in designing a wireless sensor network.

  11. A Two-Phase Coverage-Enhancing Algorithm for Hybrid Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Qingguo Zhang

    2017-01-01

    Full Text Available Providing field coverage is a key task in many sensor network applications. In certain scenarios, the sensor field may have coverage holes due to random initial deployment of sensors; thus, the desired level of coverage cannot be achieved. A hybrid wireless sensor network is a cost-effective solution to this problem, which is achieved by repositioning a portion of the mobile sensors in the network to meet the network coverage requirement. This paper investigates how to redeploy mobile sensor nodes to improve network coverage in hybrid wireless sensor networks. We propose a two-phase coverage-enhancing algorithm for hybrid wireless sensor networks. In phase one, we use a differential evolution algorithm to compute the candidate’s target positions in the mobile sensor nodes that could potentially improve coverage. In the second phase, we use an optimization scheme on the candidate’s target positions calculated from phase one to reduce the accumulated potential moving distance of mobile sensors, such that the exact mobile sensor nodes that need to be moved as well as their final target positions can be determined. Experimental results show that the proposed algorithm provided significant improvement in terms of area coverage rate, average moving distance, area coverage–distance rate and the number of moved mobile sensors, when compare with other approaches.

  12. Proton and gamma -Rays Irradiation-Induced Dark Current Random Telegraph Signal in a 0.18-mu{{m}} CMOS Image Sensor

    Science.gov (United States)

    Martin, E.; Nuns, T.; Virmontois, C.; David, J.-P.; Gilard, O.

    2013-08-01

    The dark current random telegraph signal (RTS) behavior has been studied in a five-transistor-per-pixel (5T) pinned photodiode 0.18-μm COTS active pixel sensor (APS). Several devices, irradiated using protons and gamma rays, have been studied in order to assess the ionizing and displacement damage effects. The influence of the proton energy, fluence, ionizing dose and applied bias during irradiation on the number of RTS pixels, the number of discrete levels, maximum transition amplitude, and mean switching time constants is investigated.

  13. Advanced OS deployment system

    OpenAIRE

    Galiano Molina, Sebastián

    2007-01-01

    The main project’s objective is to design and build an OS deployment system taking advantage of the Linux OS and the Open Source community developments. This means to use existing technologies that modularize the system. With this philosophy in mind, the number of developed code lines within the project is keeping as small as possible. As REMBO, the OS deployment system to develop has to be transparent to the user. This means a system with a friendly user interface and no te...

  14. Modeling EERE Deployment Programs

    Energy Technology Data Exchange (ETDEWEB)

    Cort, Katherine A.; Hostick, Donna J.; Belzer, David B.; Livingston, Olga V.

    2007-11-08

    The purpose of this report is to compile information and conclusions gathered as part of three separate tasks undertaken as part of the overall project, “Modeling EERE Deployment Programs,” sponsored by the Planning, Analysis, and Evaluation office within the Department of Energy’s Office of Energy Efficiency and Renewable Energy (EERE). The purpose of the project was to identify and characterize the modeling of deployment programs within the EERE Technology Development (TD) programs, address improvements to modeling in the near term, and note gaps in knowledge where future research is needed.

  15. Remote Systems Design & Deployment

    Energy Technology Data Exchange (ETDEWEB)

    Bailey, Sharon A.; Baker, Carl P.; Valdez, Patrick LJ

    2009-08-28

    The Pacific Northwest National Laboratory (PNNL) was tasked by Washington River Protection Solutions, LLC (WRPS) to provide information and lessons learned relating to the design, development and deployment of remote systems, particularly remote arm/manipulator systems. This report reflects PNNL’s experience with remote systems and lays out the most important activities that need to be completed to successfully design, build, deploy and operate remote systems in radioactive and chemically contaminated environments. It also contains lessons learned from PNNL’s work experiences, and the work of others in the national laboratory complex.

  16. A Sensor Management Tool for Use with NASA World Wind, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — The number of sensors that are deployed continues to increase for scientific, commercial and intelligence related applications. Quantities of sensor data are...

  17. Optimal and Approximate Approaches for Deployment of Heterogeneous Sensing Devices

    Directory of Open Access Journals (Sweden)

    Rabie Ramadan

    2007-04-01

    Full Text Available A modeling framework for the problem of deploying a set of heterogeneous sensors in a field with time-varying differential surveillance requirements is presented. The problem is formulated as mixed integer mathematical program with the objective to maximize coverage of a given field. Two metaheuristics are used to solve this problem. The first heuristic adopts a genetic algorithm (GA approach while the second heuristic implements a simulated annealing (SA algorithm. A set of experiments is used to illustrate the capabilities of the developed models and to compare their performance. The experiments investigate the effect of parameters related to the size of the sensor deployment problem including number of deployed sensors, size of the monitored field, and length of the monitoring horizon. They also examine several endogenous parameters related to the developed GA and SA algorithms.

  18. Deploying Node.js

    CERN Document Server

    Pasquali, Sandro

    2015-01-01

    If you are an intermediate or advanced developer deploying your Node.js applications, then this book is for you. If you have already built a Node application or module and want to take your knowledge to the next level, this book will help you find your way.

  19. Cooperative Technolgy Deployed

    NARCIS (Netherlands)

    Koenders, E.; Velt, R. in 't

    2011-01-01

    After the successful demonstrations of cooperative technology by the CVIS and Safespot projects the question remains how this technology can be successfully deployed. This question is explored by the Field Operational Test project FREILOT, which aims to provide fuel economy applications that must be

  20. Fusion Power Deployment

    International Nuclear Information System (INIS)

    Schmidt, J.A.; Ogden, J.M.

    2002-01-01

    Fusion power plants could be part of a future portfolio of non-carbon dioxide producing energy supplies such as wind, solar, biomass, advanced fission power, and fossil energy with carbon dioxide sequestration. In this paper, we discuss key issues that could impact fusion energy deployment during the last half of this century. These include geographic issues such as resource availability, scale issues, energy storage requirements, and waste issues. The resource needs and waste production associated with fusion deployment in the U.S. should not pose serious problems. One important feature of fusion power is the fact that a fusion power plant should be locatable within most local or regional electrical distribution systems. For this reason, fusion power plants should not increase the burden of long distance power transmission to our distribution system. In contrast to fusion power, regional factors could play an important role in the deployment of renewable resources such as wind, solar and biomass or fossil energy with CO2 sequestration. We examine the role of these regional factors and their implications for fusion power deployment

  1. Conversion of the magnetic field measured in three components on the magnetic sensor body's random coordinate system into three components on geographical coordinate system through quaternion rotation.

    Science.gov (United States)

    LIM, M.; PARK, Y.; Jung, H.; SHIN, Y.; Rim, H.; PARK, C.

    2017-12-01

    To measure all components of a physical property, for example the magnetic field, is more useful than to measure its magnitude only in interpretation and application thereafter. To convert the physical property measured in 3 components on a random coordinate system, for example on moving magnetic sensor body's coordinate system, into 3 components on a fixed coordinate system, for example on geographical coordinate system, by the rotations of coordinate system around Euler angles for example, we should have the attitude values of the sensor body in time series, which could be acquired by an INS-GNSS system of which the axes are installed coincident with those of the sensor body. But if we want to install some magnetic sensors in array at sea floor but without attitude acquisition facility of the magnetic sensors and to monitor the variation of magnetic fields in time, we should have also some way to estimate the relation between the geographical coordinate system and each sensor body's coordinate system by comparison of the vectors only measured on both coordinate systems on the assumption that the directions of the measured magnetic field on both coordinate systems are the same. For that estimation, we have at least 3 ways. The first one is to calculate 3 Euler angles phi, theta, psi from the equation Vgeograph = Rx(phi) Ry(theta) Rz(psi) Vrandom, where Vgeograph is the vector on geographical coordinate system etc. and Rx(phi) is the rotation matrix around the x axis by the angle phi etc. The second one is to calculate the difference of inclination and declination between the 2 vectors on spherical coordinate system. The third one, used by us for this study, is to calculate the angle of rotation along a great circle around the rotation axis, and the direction of the rotation axis. We installed no. 1 and no. 2 FVM-400 fluxgate magnetometers in array near Cheongyang Geomagnetic Observatory (IAGA code CYG) and acquired time series of magnetic fields for CYG and for

  2. Three-Dimensional Sensor Common Operating Picture (3-D Sensor COP)

    Science.gov (United States)

    2017-01-01

    DEMs that have been computed from the point clouds . Additionally, Fusion3D can also display 3-D data created using photogrammetry software...Picture (3-D Sensor COP). To test the 3-D Sensor COP, we took advantage of a sensor network that had been deployed for the Enterprise Challenge 2016 at...took advantage of a sensor network that had been deployed for the Enterprise Challenge 2016 (EC16) at Fort Huachuca in Sierra Vista, Arizona. The

  3. Large Deployable Reflector (LDR)

    Science.gov (United States)

    Alff, W. H.

    1980-01-01

    The feasibility and costs were determined for a 1 m to 30 m diameter ambient temperature, infrared to submillimeter orbiting astronomical telescope which is to be shuttle-deployed, free-flying, and have a 10 year orbital life. Baseline concepts, constraints on delivery and deployment, and the sunshield required are examined. Reflector concepts, the optical configuration, alignment and pointing, and materials are also discussed. Technology studies show that a 10 m to 30 m diameter system which is background and diffraction limited at 30 micron m is feasible within the stated time frame. A 10 m system is feasible with current mirror technology, while a 30 m system requires technology still in development.

  4. Deployable reflector configurations

    Science.gov (United States)

    Meinel, A. B.; Meinel, M. P.; Woolf, N. J.

    Both the theoretical reasons for considering a non-circular format for the Large Deployable Reflector, and a potentially realizable concept for such a device, are discussed. The optimum systems for diffraction limited telescopes with incoherent detection have either a single filled aperture, or two such apertures as an interferometer to synthesize a larger aperture. For a single aperture of limited area, a reflector in the form of a slot can be used to give increased angular resolution. It is shown how a 20 x 8 meter telescope can be configured to fit the Space Shuttle bay, and deployed with relatively simple operations. The relationship between the sunshield design and the inclination of the orbit is discussed. The possible use of the LDR as a basic module to permit the construction of supergiant space telescopes and interferometers both for IR/submm studies and for the entire ultraviolet through mm wave spectral region is discussed.

  5. Treatment Deployment Evaluation Tool

    International Nuclear Information System (INIS)

    M. A. Rynearson; M. M. Plum

    1999-01-01

    The U.S. Department of Energy (DOE) is responsible for the final disposition of legacy spent nuclear fuel (SNF). As a response, DOE's National Spent Nuclear Fuel Program (NSNFP) has been given the responsibility for the disposition of DOE-owned SNF. Many treatment technologies have been identified to treat some forms of SNF so that the resulting treated product is acceptable by the disposition site. One of these promising treatment processes is the electrometallurgical treatment (EMT) currently in development; a second is an Acid Wash Decladding process. The NSNFP has been tasked with identifying possible strategies for the deployment of these treatment processes in the event that a treatment path is deemed necessary. To support the siting studies of these strategies, economic evaluations are being performed to identify the least-cost deployment path. This model (tool) was developed to consider the full scope of costs, technical feasibility, process material disposition, and schedule attributes over the life of each deployment alternative. Using standard personal computer (PC) software, the model was developed as a comprehensive technology economic assessment tool using a Life-Cycle Cost (LCC) analysis methodology. Model development was planned as a systematic, iterative process of identifying and bounding the required activities to dispose of SNF. To support the evaluation process, activities are decomposed into lower level, easier to estimate activities. Sensitivity studies can then be performed on these activities, defining cost issues and testing results against the originally stated problem

  6. Sensor-Based Interactive Balance Training with Visual Joint Movement Feedback for Improving Postural Stability in Diabetics with Peripheral Neuropathy: A Randomized Controlled Trial.

    Science.gov (United States)

    Grewal, Gurtej Singh; Schwenk, Michael; Lee-Eng, Jacqueline; Parvaneh, Saman; Bharara, Manish; Menzies, Robert A; Talal, Talal K; Armstrong, David G; Najafi, Bijan

    2015-01-01

    Individuals with diabetic peripheral neuropathy (DPN) have deficits in sensory and motor skills leading to inadequate proprioceptive feedback, impaired postural balance and higher fall risk. This study investigated the effect of sensor-based interactive balance training on postural stability and daily physical activity in older adults with diabetes. Thirty-nine older adults with DPN were enrolled (age 63.7 ± 8.2 years, BMI 30.6 ± 6, 54% females) and randomized to either an intervention (IG) or a control (CG) group. The IG received sensor-based interactive exercise training tailored for people with diabetes (twice a week for 4 weeks). The exercises focused on shifting weight and crossing virtual obstacles. Body-worn sensors were implemented to acquire kinematic data and provide real-time joint visual feedback during the training. Outcome measurements included changes in center of mass (CoM) sway, ankle and hip joint sway measured during a balance test while the eyes were open and closed at baseline and after the intervention. Daily physical activities were also measured during a 48-hour period at baseline and at follow-up. Analysis of covariance was performed for the post-training outcome comparison. Compared with the CG, the patients in the IG showed a significantly reduced CoM sway (58.31%; p = 0.009), ankle sway (62.7%; p = 0.008) and hip joint sway (72.4%; p = 0.017) during the balance test with open eyes. The ankle sway was also significantly reduced in the IG group (58.8%; p = 0.037) during measurements while the eyes were closed. The number of steps walked showed a substantial but nonsignificant increase (+27.68%; p = 0.064) in the IG following training. The results of this randomized controlled trial demonstrate that people with DPN can significantly improve their postural balance with diabetes-specific, tailored, sensor-based exercise training. The results promote the use of wearable technology in exercise training; however, future studies comparing this

  7. Random mutagenesis screening indicates the absence of a separate H(+)-sensor in the pH-sensitive Kir channels.

    Science.gov (United States)

    Paynter, Jennifer J; Shang, Lijun; Bollepalli, Murali K; Baukrowitz, Thomas; Tucker, Stephen J

    2010-01-01

    Several inwardly-rectifying (Kir) potassium channels (Kir1.1, Kir4.1 and Kir4.2) are characterised by their sensitivity to inhibition by intracellular H(+) within the physiological range. The mechanism by which these channels are regulated by intracellular pH has been the subject of intense scrutiny for over a decade, yet the molecular identity of the titratable pH-sensor remains elusive. In this study we have taken advantage of the acidic intracellular environment of S. cerevisiae and used a K(+) -auxotrophic strain to screen for mutants of Kir1.1 with impaired pH-sensitivity. In addition to the previously identified K80M mutation, this unbiased screening approach identified a novel mutation (S172T) in the second transmembrane domain (TM2) that also produces a marked reduction in pH-sensitivity through destabilization of the closed-state. However, despite this extensive mutagenic approach, no mutations could be identified which removed channel pH-sensitivity or which were likely to act as a separate H(+) -sensor unique to the pH-sensitive Kir channels. In order to explain these results we propose a model in which the pH-sensing mechanism is part of an intrinsic gating mechanism common to all Kir channels, not just the pH-sensitive Kir channels. In this model, mutations which disrupt this pH-sensor would result in an increase, not reduction, in pH-sensitivity. This has major implications for any future studies of Kir channel pH-sensitivity and explains why formal identification of these pH-sensing residues still represents a major challenge.

  8. Node Scheduling Strategies for Achieving Full-View Area Coverage in Camera Sensor Networks

    Science.gov (United States)

    Wu, Peng-Fei; Xiao, Fu; Sha, Chao; Huang, Hai-Ping; Wang, Ru-Chuan; Xiong, Nai-Xue

    2017-01-01

    Unlike conventional scalar sensors, camera sensors at different positions can capture a variety of views of an object. Based on this intrinsic property, a novel model called full-view coverage was proposed. We study the problem that how to select the minimum number of sensors to guarantee the full-view coverage for the given region of interest (ROI). To tackle this issue, we derive the constraint condition of the sensor positions for full-view neighborhood coverage with the minimum number of nodes around the point. Next, we prove that the full-view area coverage can be approximately guaranteed, as long as the regular hexagons decided by the virtual grid are seamlessly stitched. Then we present two solutions for camera sensor networks in two different deployment strategies. By computing the theoretically optimal length of the virtual grids, we put forward the deployment pattern algorithm (DPA) in the deterministic implementation. To reduce the redundancy in random deployment, we come up with a local neighboring-optimal selection algorithm (LNSA) for achieving the full-view coverage. Finally, extensive simulation results show the feasibility of our proposed solutions. PMID:28587304

  9. Node Scheduling Strategies for Achieving Full-View Area Coverage in Camera Sensor Networks

    Directory of Open Access Journals (Sweden)

    Peng-Fei Wu

    2017-06-01

    Full Text Available Unlike conventional scalar sensors, camera sensors at different positions can capture a variety of views of an object. Based on this intrinsic property, a novel model called full-view coverage was proposed. We study the problem that how to select the minimum number of sensors to guarantee the full-view coverage for the given region of interest (ROI. To tackle this issue, we derive the constraint condition of the sensor positions for full-view neighborhood coverage with the minimum number of nodes around the point. Next, we prove that the full-view area coverage can be approximately guaranteed, as long as the regular hexagons decided by the virtual grid are seamlessly stitched. Then we present two solutions for camera sensor networks in two different deployment strategies. By computing the theoretically optimal length of the virtual grids, we put forward the deployment pattern algorithm (DPA in the deterministic implementation. To reduce the redundancy in random deployment, we come up with a local neighboring-optimal selection algorithm (LNSA for achieving the full-view coverage. Finally, extensive simulation results show the feasibility of our proposed solutions.

  10. Optimal Control of a Surge-Mode WEC in Random Waves

    Energy Technology Data Exchange (ETDEWEB)

    Chertok, Allan [Resolute Marine Energy, Inc., Boston, MA (United States); Ceberio, Olivier [Resolute Marine Energy, Inc., Boston, MA (United States); Staby, Bill [Resolute Marine Energy, Inc., Boston, MA (United States); Previsic, Mirko [Re Vision Consulting, Sacramento, CA (United States); Scruggs, Jeffrey [Univ. of Michigan, Ann Arbor, MI (United States); Van de Ven, James [Univ. of Minnesota, Minneapolis, MN (United States)

    2016-08-30

    The objective of this project was to develop one or more real-time feedback and feed-forward (MPC) control algorithms for an Oscillating Surge Wave Converter (OSWC) developed by RME called SurgeWEC™ that leverages recent innovations in wave energy converter (WEC) control theory to maximize power production in random wave environments. The control algorithms synthesized innovations in dynamic programming and nonlinear wave dynamics using anticipatory wave sensors and localized sensor measurements; e.g. position and velocity of the WEC Power Take Off (PTO), with predictive wave forecasting data. The result was an advanced control system that uses feedback or feed-forward data from an array of sensor channels comprised of both localized and deployed sensors fused into a single decision process that optimally compensates for uncertainties in the system dynamics, wave forecasts, and sensor measurement errors.

  11. Dynamic Sensor Network Reprogramming using SensorScheme

    NARCIS (Netherlands)

    Evers, L.; Havinga, Paul J.M.; Kuper, Jan

    2007-01-01

    Building wireless sensor network applications is a challenging task, and it has become apparent that it is crucial for many sensor networks to be able to load or update the application after deployment. Since communication is a scarce resource and costly in terms of energy, it is important to

  12. Calibration procedure for Slocum glider deployed optical instruments.

    Science.gov (United States)

    Cetinić, Ivona; Toro-Farmer, Gerardo; Ragan, Matthew; Oberg, Carl; Jones, Burton H

    2009-08-31

    Recent developments in the field of the autonomous underwater vehicles allow the wide usage of these platforms as part of scientific experiments, monitoring campaigns and more. The vehicles are often equipped with sensors measuring temperature, conductivity, chlorophyll a fluorescence (Chl a), colored dissolved organic matter (CDOM) fluorescence, phycoerithrin (PE) fluorescence and spectral volume scattering function at 117 degrees, providing users with high resolution, real time data. However, calibration of these instruments can be problematic. Most in situ calibrations are performed by deploying complementary instrument packages or water samplers in the proximity of the glider. Laboratory calibrations of the mounted sensors are difficult due to the placement of the instruments within the body of the vehicle. For the laboratory calibrations of the Slocum glider instruments we developed a small calibration chamber where we can perform precise calibrations of the optical instruments aboard our glider, as well as sensors from other deployment platforms. These procedures enable us to obtain pre- and post-deployment calibrations for optical fluorescence instruments, which may differ due to the biofouling and other physical damage that can occur during long-term glider deployments. We found that biofouling caused significant changes in the calibration scaling factors of fluorescent sensors, suggesting the need for consistent and repetitive calibrations for gliders as proposed in this paper.

  13. Economics of ALMR deployment

    International Nuclear Information System (INIS)

    Delene, J.G.; Fuller, L.C.; Hudson, C.R.

    1994-01-01

    The Advanced Liquid Metal Reactor (ALMR) has the potential to extend the economic life of the nuclear option and of reducing the number of high level waste repositories which will eventually be needed in an expanding nuclear economy. This paper reports on an analysis which models and evaluates the economics of the use of ALMRs as a component of this country's future electricity generation mix. The ALMR concept has the ability to utilize as fuel the fissile material contained in previously irradiated nuclear fuel (i.e., spent fuel) or from surplus weapons grade material. While not a requirement for the successful deployment of ALMR power plant technology, the reprocessing of spent fuel from light water reactors (LWR) is necessary for any rapid introduction of ALMR power plants. In addition, the reprocessing of LWR spent fuel may reduce the number of high level waste repositories needed in the future by burning the long-lived actinides produced in the fission process. With this study, the relative economics of a number of potential scenarios related to these issues are evaluated. While not encompassing the full range of all possibilities, the cases reported here provide an indication of the potential costs, timings, and relative economic attractiveness of ALMR deployment

  14. ALMR deployment economic analysis

    International Nuclear Information System (INIS)

    Delene, J.G.; Fuller, L.C.; Hudson, C.R.

    1993-06-01

    This analysis seeks to model and evaluate the economics of the use of Advanced Liquid Metal Reactors (ALMR) as a component of this country's future electricity generation mix. The ALMR concept has the ability to utilize as fuel the fissile material contained in previously irradiated nuclear fuel (i.e., spent fuel). While not a requirement for the successful deployment of ALMR power plant technology, the reprocessing of spent fuel from light water reactors (LWR) is necessary for any rapid introduction of ALMR power plants. In addition, the reprocessing of LWR spent fuel may reduce the number of high level waste repositories needed in the future by burning the long-lived actinides produced in the fission process. With this study, the relative economics of a number of potential scenarios related to these issues are evaluated. While not encompassing the full range of all possibilities, the cases reported here provide an indication of the potential costs, timings, and relative economic attractiveness of ALMR deployment

  15. Fiber-Optic Shape Sensing for Intelligent Solar Sail Deployment, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Luna Innovations proposes to develop a distributed fiber-optic shape sensor to provide a control system for the deployment of ultra-lightweight inflatable support...

  16. Integration and analysis of neighbor discovery and link quality estimation in wireless sensor networks.

    Science.gov (United States)

    Radi, Marjan; Dezfouli, Behnam; Abu Bakar, Kamalrulnizam; Abd Razak, Shukor

    2014-01-01

    Network connectivity and link quality information are the fundamental requirements of wireless sensor network protocols to perform their desired functionality. Most of the existing discovery protocols have only focused on the neighbor discovery problem, while a few number of them provide an integrated neighbor search and link estimation. As these protocols require a careful parameter adjustment before network deployment, they cannot provide scalable and accurate network initialization in large-scale dense wireless sensor networks with random topology. Furthermore, performance of these protocols has not entirely been evaluated yet. In this paper, we perform a comprehensive simulation study on the efficiency of employing adaptive protocols compared to the existing nonadaptive protocols for initializing sensor networks with random topology. In this regard, we propose adaptive network initialization protocols which integrate the initial neighbor discovery with link quality estimation process to initialize large-scale dense wireless sensor networks without requiring any parameter adjustment before network deployment. To the best of our knowledge, this work is the first attempt to provide a detailed simulation study on the performance of integrated neighbor discovery and link quality estimation protocols for initializing sensor networks. This study can help system designers to determine the most appropriate approach for different applications.

  17. Integration and Analysis of Neighbor Discovery and Link Quality Estimation in Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Marjan Radi

    2014-01-01

    Full Text Available Network connectivity and link quality information are the fundamental requirements of wireless sensor network protocols to perform their desired functionality. Most of the existing discovery protocols have only focused on the neighbor discovery problem, while a few number of them provide an integrated neighbor search and link estimation. As these protocols require a careful parameter adjustment before network deployment, they cannot provide scalable and accurate network initialization in large-scale dense wireless sensor networks with random topology. Furthermore, performance of these protocols has not entirely been evaluated yet. In this paper, we perform a comprehensive simulation study on the efficiency of employing adaptive protocols compared to the existing nonadaptive protocols for initializing sensor networks with random topology. In this regard, we propose adaptive network initialization protocols which integrate the initial neighbor discovery with link quality estimation process to initialize large-scale dense wireless sensor networks without requiring any parameter adjustment before network deployment. To the best of our knowledge, this work is the first attempt to provide a detailed simulation study on the performance of integrated neighbor discovery and link quality estimation protocols for initializing sensor networks. This study can help system designers to determine the most appropriate approach for different applications.

  18. Complex Deployed Responsive Service

    Science.gov (United States)

    Parry, Glenn; McLening, Marc; Caldwell, Nigel; Thompson, Rob

    A pizza restaurant must provide product, in the form of the food and drink, and service in the way this is delivered to the customer. Providing this has distinct operational challenges, but what if the restaurant also provides a home delivery service? The service becomes deployed as the customer is no-longer co-located with the production area. The business challenge is complicated as service needs to be delivered within a geographic region, to time or the pizza will be cold, and within a cost that is not ­prohibitive. It must also be responsive to short term demand; needing to balance the number of staff it has available to undertake deliveries against a forecast of demand.

  19. CCT deployment considerations

    International Nuclear Information System (INIS)

    Yamagata, B.

    1993-01-01

    The deployment of Clean Coal Technologies (CCT) is discussed by asserting that in the case of commercializing CCT, the government's involvement should not stop at the demonstration gate. Two areas in this regard are described. First, the need for the domestic DOE CCT Program to focus on the domestic deployment of demonstrated technologies, and second, the need to recognize that to participate in the phenomenal growth of international power markets through use of clean coal or advanced coal technologies an aggressive partnering between the government and industry to demonstrate technologies abroad will be required. The Clean Coal Technology Coalition's (CCT) primary mission has been to promote the development and use of CCTs. The CCT is a strong advocate for the DOE CCT Program and applauds the Department's and industry's success at developing many coal-based technologies. By current design, the DOE program is said to go no further than the initial demonstration of a technology. Since the inception of CCT in 1986, the Coalition has advocated the need to pursue a partnership with government in which more than one demonstration of the same or similar technology is supported by the clean coal program. Only in this way can one be assured of widespread acceptance of any given technology. There exists a gap (call it a open-quotes risk gapclose quotes) between CCTs that have been successfully demonstrated (and presumably available for commercial use) and their widespread commercial use. A technology matrix has been developed in which the developmental status of a variety of clean coal technologies is demonstrated. While still too early to pass judgment, it appears that while success is being achieved in demonstrating advanced coal technologies, the market place - for several reasons - is not, indeed may have no plans, to adopt these technologies

  20. Wireless Sensor Network Safety Study

    OpenAIRE

    M.Shankar; Dr.M.Sridar; Dr.M.Rajani

    2012-01-01

    Few security mechanisms in wireless sensor networks (WSNs) have been implemented, and even fewer have been applied in real deployments. The limited resources of each sensor node makes security in WSNs hard, as the tradeoff between security and practicality must be carefully considered. These complex systems include in their design different types of information and communication technology systems, such as wireless (mesh) sensor networks, to carry out control processes in real time. This fact...

  1. CMS software deployment on OSG

    International Nuclear Information System (INIS)

    Kim, B; Avery, P; Thomas, M; Wuerthwein, F

    2008-01-01

    A set of software deployment tools has been developed for the installation, verification, and removal of a CMS software release. The tools that are mainly targeted for the deployment on the OSG have the features of instant release deployment, corrective resubmission of the initial installation job, and an independent web-based deployment portal with Grid security infrastructure login mechanism. We have been deploying over 500 installations and found the tools are reliable and adaptable to cope with problems with changes in the Grid computing environment and the software releases. We present the design of the tools, statistics that we gathered during the operation of the tools, and our experience with the CMS software deployment on the OSG Grid computing environment

  2. CMS software deployment on OSG

    Energy Technology Data Exchange (ETDEWEB)

    Kim, B; Avery, P [University of Florida, Gainesville, FL 32611 (United States); Thomas, M [California Institute of Technology, Pasadena, CA 91125 (United States); Wuerthwein, F [University of California at San Diego, La Jolla, CA 92093 (United States)], E-mail: bockjoo@phys.ufl.edu, E-mail: thomas@hep.caltech.edu, E-mail: avery@phys.ufl.edu, E-mail: fkw@fnal.gov

    2008-07-15

    A set of software deployment tools has been developed for the installation, verification, and removal of a CMS software release. The tools that are mainly targeted for the deployment on the OSG have the features of instant release deployment, corrective resubmission of the initial installation job, and an independent web-based deployment portal with Grid security infrastructure login mechanism. We have been deploying over 500 installations and found the tools are reliable and adaptable to cope with problems with changes in the Grid computing environment and the software releases. We present the design of the tools, statistics that we gathered during the operation of the tools, and our experience with the CMS software deployment on the OSG Grid computing environment.

  3. Efficiency Evaluation of Strategies for Dynamic Management of Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Andrea Verônica González

    2017-01-01

    Full Text Available This paper presents and evaluates dynamic management strategies to improve efficiency in event-triggered wireless sensor networks. We are considering mobility, where nodes move themselves to maximize the coverage, and load balancing state-of-the-art techniques, by which the number of nodes sensing the same area is reduced. To explore mobility, we present a simple method by which nodes can dynamically reorganize themselves based on the force fields approach of mobile robotics. Firstly, the strategies are evaluated separately through experiments with different network configurations and, afterwards, a joint evaluation has been conducted to observe the impact of mobility on the efficiency of load balancing techniques. We show that mobile nodes significantly contribute to keeping the coverage as nodes die in mesh and powerfully improving it in random deployments. Load balancing techniques achieve important results, increasing lifetime and the number of sensed events. However, in random deployments, these techniques lose efficiency and become unsuitable strategies. Combining these strategies with mobility, we observe that PS-based technique keeps its contribution in mesh and random deployments, as well as improving its performance for not so dense networks. Ant-based technique when combined with mobile nodes loses performance significantly in mesh and keeps its good performance in random deployed and less dense networks.

  4. Virtual Sensor Test Instrumentation

    Science.gov (United States)

    Wang, Roy

    2011-01-01

    Virtual Sensor Test Instrumentation is based on the concept of smart sensor technology for testing with intelligence needed to perform sell-diagnosis of health, and to participate in a hierarchy of health determination at sensor, process, and system levels. A virtual sensor test instrumentation consists of five elements: (1) a common sensor interface, (2) microprocessor, (3) wireless interface, (4) signal conditioning and ADC/DAC (analog-to-digital conversion/ digital-to-analog conversion), and (5) onboard EEPROM (electrically erasable programmable read-only memory) for metadata storage and executable software to create powerful, scalable, reconfigurable, and reliable embedded and distributed test instruments. In order to maximize the efficient data conversion through the smart sensor node, plug-and-play functionality is required to interface with traditional sensors to enhance their identity and capabilities for data processing and communications. Virtual sensor test instrumentation can be accessible wirelessly via a Network Capable Application Processor (NCAP) or a Smart Transducer Interlace Module (STIM) that may be managed under real-time rule engines for mission-critical applications. The transducer senses the physical quantity being measured and converts it into an electrical signal. The signal is fed to an A/D converter, and is ready for use by the processor to execute functional transformation based on the sensor characteristics stored in a Transducer Electronic Data Sheet (TEDS). Virtual sensor test instrumentation is built upon an open-system architecture with standardized protocol modules/stacks to interface with industry standards and commonly used software. One major benefit for deploying the virtual sensor test instrumentation is the ability, through a plug-and-play common interface, to convert raw sensor data in either analog or digital form, to an IEEE 1451 standard-based smart sensor, which has instructions to program sensors for a wide variety of

  5. Hole Detection for Quantifying Connectivity in Wireless Sensor Networks: A Survey

    Directory of Open Access Journals (Sweden)

    Pearl Antil

    2014-01-01

    Full Text Available Owing to random deployment, environmental factors, dynamic topology, and external attacks, emergence of holes in wireless sensor networks is inescapable. Hole is an area in sensor network around which sensors cease to sense or communicate due to drainage of battery or any fault, either temporary or permanent. Holes impair sensing and communication functions of network; thus their identification is a major concern. This paper discusses different types of holes and significance of hole detection in wireless sensor networks. Coverage hole detection schemes have been classified into three categories based on the type of information used by algorithms, computation model, and network dynamics for better understanding. Then, relative strengths and shortcomings of some of the existing coverage hole detection algorithms are discussed. The paper is concluded by highlighting various future research directions.

  6. Performance Analysis of Receive Diversity in Wireless Sensor Networks over GBSBE Models

    Directory of Open Access Journals (Sweden)

    Tai-hoon Kim

    2010-12-01

    Full Text Available Wireless sensor networks have attracted a lot of attention recently. In this paper, we develop a channel model based on the elliptical model for multipath components involving randomly placed scatterers in the scattering region with sensors deployed on a field. We verify that in a sensor network, the use of receive diversity techniques improves the performance of the system. Extensive performance analysis of the system is carried out for both single and multiple antennas with the applied receive diversity techniques. Performance analyses based on variations in receiver height, maximum multipath delay and transmit power have been performed considering different numbers of antenna elements present in the receiver array, Our results show that increasing the number of antenna elements for a wireless sensor network does indeed improve the BER rates that can be obtained.

  7. Performance Analysis of Receive Diversity in Wireless Sensor Networks over GBSBE Models

    Science.gov (United States)

    Goel, Shivali; Abawajy, Jemal H.; Kim, Tai-hoon

    2010-01-01

    Wireless sensor networks have attracted a lot of attention recently. In this paper, we develop a channel model based on the elliptical model for multipath components involving randomly placed scatterers in the scattering region with sensors deployed on a field. We verify that in a sensor network, the use of receive diversity techniques improves the performance of the system. Extensive performance analysis of the system is carried out for both single and multiple antennas with the applied receive diversity techniques. Performance analyses based on variations in receiver height, maximum multipath delay and transmit power have been performed considering different numbers of antenna elements present in the receiver array, Our results show that increasing the number of antenna elements for a wireless sensor network does indeed improve the BER rates that can be obtained. PMID:22163510

  8. Mastering Hyper-V Deployment

    CERN Document Server

    Finn, Aidan

    2010-01-01

    The only book to take an in-depth look at deploying Hyper-V. Now in its second generation, the popular Hyper-V boasts technical advances that create even more dynamic systems than ever before. This unique resource serves an authoritative guide to deploying Windows Server 2008 R2 Hyper-V comprehensively. Step-by-step instructions demonstrate how to design a Hyper-V deployment, build a Hyper-V host environment, and design a management system with System Center Virtual Machine Manager 2008 R2.: Features real-world examples that show you how to design a Hyper-V deployment, build a Hyper-V host env

  9. Infrastructure Engineering and Deployment Division

    Data.gov (United States)

    Federal Laboratory Consortium — Volpe's Infrastructure Engineering and Deployment Division advances transportation innovation by being leaders in infrastructure technology, including vehicles and...

  10. Can validated wrist devices with position sensors replace arm devices for self-home blood pressure monitoring? A randomized crossover trial using ambulatory monitoring as reference.

    Science.gov (United States)

    Stergiou, George S; Christodoulakis, George R; Nasothimiou, Efthimia G; Giovas, Periklis P; Kalogeropoulos, Petros G

    2008-07-01

    Electronic devices that measure blood pressure (BP) at the arm level are regarded as more accurate than wrist devices and are preferred for home BP (HBP) monitoring. Recently, wrist devices with position sensors have been successfully validated using established protocols. This study assessed whether HBP values measured with validated wrist devices are sufficiently reliable to be used for making patient-related decisions in clinical practice. This randomized crossover study compared HBP measurements taken using validated wrist devices (wrist-HBP, Omron R7 with position sensor) with those taken using arm devices (arm-HBP, Omron 705IT), and also with measurements of awake ambulatory BP (ABP, SpaceLabs), in 79 subjects (36 men and 43 women) with hypertension. The mean age of the study population was 56.7 +/- 11.8 years, and 33 of the subjects were not under treatment for hypertension. The average arm-HBP was higher than the average wrist-HBP (mean difference, systolic 5.2 +/- 9.1 mm Hg, P or =10 mm Hg difference between systolic wrist-HBP and arm-HBP and twelve subjects (15%) showed similar levels of disparity in diastolic HBP readings. Strong correlations were found between arm-HBP and wrist-HBP (r 0.74/0.74, systolic/diastolic, P arm-HBP (r 0.73/0.76) than with wrist-HBP (0.55/0.69). The wrist-arm HBP difference was associated with systolic ABP (r 0.34) and pulse pressure (r 0.29), but not with diastolic ABP, sex, age, arm circumference, and wrist circumference. There might be important differences in HBP measured using validated wrist devices with position sensor vs. arm devices, and these could impact decisions relating to the patient in clinical practice. Measurements taken using arm devices are more closely related to ABP values than those recorded by wrist devices. More research is needed before recommending the widespread use of wrist monitors in clinical practice. American Journal of Hypertension doi:10.1038/ajh.2008.176American Journal of Hypertension (2008

  11. Sleep Deprivation Attack Detection in Wireless Sensor Network

    Science.gov (United States)

    Bhattasali, Tapalina; Chaki, Rituparna; Sanyal, Sugata

    2012-02-01

    Deployment of sensor network in hostile environment makes it mainly vulnerable to battery drainage attacks because it is impossible to recharge or replace the battery power of sensor nodes. Among different types of security threats, low power sensor nodes are immensely affected by the attacks which cause random drainage of the energy level of sensors, leading to death of the nodes. The most dangerous type of attack in this category is sleep deprivation, where target of the intruder is to maximize the power consumption of sensor nodes, so that their lifetime is minimized. Most of the existing works on sleep deprivation attack detection involve a lot of overhead, leading to poor throughput. The need of the day is to design a model for detecting intrusions accurately in an energy efficient manner. This paper proposes a hierarchical framework based on distributed collaborative mechanism for detecting sleep deprivation torture in wireless sensor network efficiently. Proposed model uses anomaly detection technique in two steps to reduce the probability of false intrusion.

  12. Embedded sensor systems

    CERN Document Server

    Agrawal, Dharma Prakash

    2017-01-01

    This inspiring textbook provides an introduction to wireless technologies for sensors, explores potential use of sensors for numerous applications, and utilizes probability theory and mathematical methods as a means of embedding sensors in system design. It discusses the need for synchronization and underlying limitations, inter-relation between given coverage and connectivity to number of sensors needed, and the use of geometrical distance to determine location of the base station for data collection and explore use of anchor nodes for relative position determination of sensors. The book explores energy conservation, communication using TCP, the need for clustering and data aggregation, and residual energy determination and energy harvesting. It covers key topics of sensor communication like mobile base stations and relay nodes, delay-tolerant sensor networks, and remote sensing and possible applications. The book defines routing methods and do performance evaluation for random and regular sensor topology an...

  13. Miniature sensor suitable for electronic nose applications

    DEFF Research Database (Denmark)

    Pinnaduwage, L. A.; Gehl, A. C.; Allman, S. L.

    2007-01-01

    A major research effort has been devoted over the years for the development of chemical sensors for the detection of chemical and explosive vapors. However, the deployment of such chemical sensors will require the use of multiple sensors probably tens of sensors in a sensor package to achieve sel...... microcantilevers. The sensor can detect parts-per-trillion concentrations of DMMP within 10 s exposure times. The small size of the sensor makes it ideally suited for electronic nose applications. © 2007 American Institute of Physics....

  14. 2-Sensor Problem

    Directory of Open Access Journals (Sweden)

    Michael Segal

    2004-11-01

    Full Text Available Abstract: Ad-hoc networks of sensor nodes are in general semi-permanently deployed. However, the topology of such networks continuously changes over time, due to the power of some sensors wearing out to new sensors being inserted into the network, or even due to designers moving sensors around during a network re-design phase (for example, in response to a change in the requirements of the network. In this paper, we address the problem of covering a given path by a limited number of sensors — in our case to two, and show its relation to the well-studied matrix multiplication problem.

  15. Wireless sensor network for monitoring soil moisture and weather conditions

    Science.gov (United States)

    A wireless sensor network (WSN) was developed and deployed in three fields to monitor soil water status and collect weather data for irrigation scheduling. The WSN consists of soil-water sensors, weather sensors, wireless data loggers, and a wireless modem. Soil-water sensors were installed at three...

  16. Mechanisms for Prolonging Network Lifetime in Wireless Sensor Networks

    Science.gov (United States)

    Yang, Yinying

    2010-01-01

    Sensors are used to monitor and control the physical environment. A Wireless Sensor Network (WSN) is composed of a large number of sensor nodes that are densely deployed either inside the phenomenon or very close to it [18][5]. Sensor nodes measure various parameters of the environment and transmit data collected to one or more sinks, using…

  17. Semantically-Enabled Sensor Plug & Play for the Sensor Web

    Science.gov (United States)

    Bröring, Arne; Maúe, Patrick; Janowicz, Krzysztof; Nüst, Daniel; Malewski, Christian

    2011-01-01

    Environmental sensors have continuously improved by becoming smaller, cheaper, and more intelligent over the past years. As consequence of these technological advancements, sensors are increasingly deployed to monitor our environment. The large variety of available sensor types with often incompatible protocols complicates the integration of sensors into observing systems. The standardized Web service interfaces and data encodings defined within OGC’s Sensor Web Enablement (SWE) framework make sensors available over the Web and hide the heterogeneous sensor protocols from applications. So far, the SWE framework does not describe how to integrate sensors on-the-fly with minimal human intervention. The driver software which enables access to sensors has to be implemented and the measured sensor data has to be manually mapped to the SWE models. In this article we introduce a Sensor Plug & Play infrastructure for the Sensor Web by combining (1) semantic matchmaking functionality, (2) a publish/subscribe mechanism underlying the SensorWeb, as well as (3) a model for the declarative description of sensor interfaces which serves as a generic driver mechanism. We implement and evaluate our approach by applying it to an oil spill scenario. The matchmaking is realized using existing ontologies and reasoning engines and provides a strong case for the semantic integration capabilities provided by Semantic Web research. PMID:22164033

  18. Security Techniques for Sensor Systems and the Internet of Things

    Science.gov (United States)

    Midi, Daniele

    2016-01-01

    Sensor systems are becoming pervasive in many domains, and are recently being generalized by the Internet of Things (IoT). This wide deployment, however, presents significant security issues. We develop security techniques for sensor systems and IoT, addressing all security management phases. Prior to deployment, the nodes need to be hardened. We…

  19. Wireless Sensor Networks TestBed: ASNTbed

    CSIR Research Space (South Africa)

    Dludla, AG

    2013-05-01

    Full Text Available Wireless sensor networks (WSNs) have been used in different types of applications and deployed within various environments. Simulation tools are essential for studying WSNs, especially for exploring large-scale networks. However, WSN testbeds...

  20. A 7 ke-SD-FWC 1.2 e-RMS Temporal Random Noise 128×256 Time-Resolved CMOS Image Sensor With Two In-Pixel SDs for Biomedical Applications.

    Science.gov (United States)

    Seo, Min-Woong; Kawahito, Shoji

    2017-12-01

    A large full well capacity (FWC) for wide signal detection range and low temporal random noise for high sensitivity lock-in pixel CMOS image sensor (CIS) embedded with two in-pixel storage diodes (SDs) has been developed and presented in this paper. For fast charge transfer from photodiode to SDs, a lateral electric field charge modulator (LEFM) is used for the developed lock-in pixel. As a result, the time-resolved CIS achieves a very large SD-FWC of approximately 7ke-, low temporal random noise of 1.2e-rms at 20 fps with true correlated double sampling operation and fast intrinsic response less than 500 ps at 635 nm. The proposed imager has an effective pixel array of and a pixel size of . The sensor chip is fabricated by Dongbu HiTek 1P4M 0.11 CIS process.

  1. Rapid deployment intrusion detection system

    International Nuclear Information System (INIS)

    Graham, R.H.

    1997-01-01

    A rapidly deployable security system is one that provides intrusion detection, assessment, communications, and annunciation capabilities; is easy to install and configure; can be rapidly deployed, and is reusable. A rapidly deployable intrusion detection system (RADIDS) has many potential applications within the DOE Complex: back-up protection for failed zones in a perimeter intrusion detection and assessment system, intrusion detection and assessment capabilities in temporary locations, protection of assets during Complex reconfiguration, and protection in hazardous locations, protection of assets during Complex reconfiguration, and protection in hazardous locations. Many DOE user-need documents have indicated an interest in a rapidly deployable intrusion detection system. The purpose of the RADIDS project is to design, develop, and implement such a system. 2 figs

  2. Family Reintegration Following Guard Deployment

    Science.gov (United States)

    2010-09-20

    Somalia Peacekeepers. Journal of Consulting and Clinical Psychology, 72(5), 909-913. Haas DM . Pazdernik LA. Olsen CH. A cross-sectional survey of the...relationship between partner deployment and stress in pregnancy during wartime. Haas DM . Pazdernik LA. Partner deployment and stress in pregnant...Identify 3-5 key words relating to the proposal. (Required) I used MESH Headings instead of the CRISP Thesaurus for key

  3. Wireless Power Transfer for Distributed Estimation in Sensor Networks

    Science.gov (United States)

    Mai, Vien V.; Shin, Won-Yong; Ishibashi, Koji

    2017-04-01

    This paper studies power allocation for distributed estimation of an unknown scalar random source in sensor networks with a multiple-antenna fusion center (FC), where wireless sensors are equipped with radio-frequency based energy harvesting technology. The sensors' observation is locally processed by using an uncoded amplify-and-forward scheme. The processed signals are then sent to the FC, and are coherently combined at the FC, at which the best linear unbiased estimator (BLUE) is adopted for reliable estimation. We aim to solve the following two power allocation problems: 1) minimizing distortion under various power constraints; and 2) minimizing total transmit power under distortion constraints, where the distortion is measured in terms of mean-squared error of the BLUE. Two iterative algorithms are developed to solve the non-convex problems, which converge at least to a local optimum. In particular, the above algorithms are designed to jointly optimize the amplification coefficients, energy beamforming, and receive filtering. For each problem, a suboptimal design, a single-antenna FC scenario, and a common harvester deployment for colocated sensors, are also studied. Using the powerful semidefinite relaxation framework, our result is shown to be valid for any number of sensors, each with different noise power, and for an arbitrarily number of antennas at the FC.

  4. Introduction to wireless sensor networks

    CERN Document Server

    Forster, Anna

    2016-01-01

    Explores real-world wireless sensor network development, deployment, and applications. The book begins with an introduction to wireless sensor networks and their fundamental concepts. Hardware components, operating systems, protocols, and algorithms that make up the anatomy of a sensor node are described in chapter two. Properties of wireless communications, medium access protocols, wireless links, and link estimation protocols are described in chapter three and chapter four. Routing basics and metrics, clustering techniques, time synchronization and localization protocols, as well as sensing techniques are introduced in chapter five to nine. The concluding chapter summarizes the learnt methods and shows how to use them to deploy real-world sensor networks in a structured way.

  5. IPv6 deployment and management

    CERN Document Server

    Dooley, Michael

    2013-01-01

    A guide for understanding, deploying, and managing Internet Protocol version 6 The growth of the Internet has created a need for more addresses than are available with Internet Protocol version 4 (IPv4)-the protocol currently used to direct almost all Internet traffic. Internet Protocol version 6 (IPv6)-the new IP version intended to ultimately succeed IPv4-will expand the addressing capacity of the Internet to support the explosive growth of users and devices on the Internet as well as add flexibility to allocating addresses and efficiency for routing traffic. IPv6 Deploy

  6. Data Dissemination in Mobile Phone Sensor Networks

    NARCIS (Netherlands)

    Le Viet Duc, Duc Viet

    Deploying sensors over large areas is costly in terms of configuration, hardware, and maintenance. Using onboard sensors of today mobile phones can significantly reduce the expenses in monitoring areas and disseminating events or data. Via the available short-range Bluetooth and/or WiFi interfaces,

  7. Wearable Sensor/Device (Fitbit One) and SMS Text-Messaging Prompts to Increase Physical Activity in Overweight and Obese Adults: A Randomized Controlled Trial

    Science.gov (United States)

    Cadmus-Bertram, Lisa A.; Natarajan, Loki; White, Martha M.; Madanat, Hala; Nichols, Jeanne F.; Ayala, Guadalupe X.; Pierce, John P.

    2015-01-01

    Abstract Background: Studies have shown self-monitoring can modify health behaviors, including physical activity (PA). This study tested the utility of a wearable sensor/device (Fitbit® One™; Fitbit Inc., San Francisco, CA) and short message service (SMS) text-messaging prompts to increase PA in overweight and obese adults. Materials and Methods: Sixty-seven adults wore a Fitbit One tracker for 6 weeks; half were randomized to also receive three daily SMS-based PA prompts. The Fitbit One consisted of a wearable tracker for instant feedback on performance and a Web site/mobile application (app) for detailed summaries. Outcome measures were objectively measured steps and minutes of PA by intensity using two accelerometers: Actigraph™ (Pensacola, FL) GT3X+ (primary measure) at baseline and Week 6 and Fitbit One (secondary measure) at baseline and Weeks 1, 2, 3, 4, 5, and 6. Results: Mixed-model repeated-measures analysis of primary measures indicated a significant within-group increase of +4.3 (standard error [SE]=2.0) min/week of moderate- to vigorous-intensity PA (MVPA) at 6-week follow-up (p=0.04) in the comparison group (Fitbit only), but no study group differences across PA levels. Secondary measures indicated the SMS text-messaging effect lasted for only 1 week: the intervention group increased by +1,266 steps (SE=491; p=0.01), +17.8 min/week MVPA (SE=8.5; p=0.04), and +38.3 min/week total PA (SE=15.9; p=0.02) compared with no changes in the comparison group, and these between-group differences were significant for steps (p=0.01), fairly/very active minutes (p<0.01), and total active minutes (p=0.02). Conclusions: These data suggest that the Fitbit One achieved a small increase in MVPA at follow-up and that the SMS-based PA prompts were insufficient in increasing PA beyond 1 week. Future studies can test this intervention in those requiring less help and/or test strategies to increase participants' engagement levels. PMID:26431257

  8. An energy-efficient and secure hybrid algorithm for wireless sensor networks using a mobile data collector

    Science.gov (United States)

    Dayananda, Karanam Ravichandran; Straub, Jeremy

    2017-05-01

    This paper proposes a new hybrid algorithm for security, which incorporates both distributed and hierarchal approaches. It uses a mobile data collector (MDC) to collect information in order to save energy of sensor nodes in a wireless sensor network (WSN) as, in most networks, these sensor nodes have limited energy. Wireless sensor networks are prone to security problems because, among other things, it is possible to use a rogue sensor node to eavesdrop on or alter the information being transmitted. To prevent this, this paper introduces a security algorithm for MDC-based WSNs. A key use of this algorithm is to protect the confidentiality of the information sent by the sensor nodes. The sensor nodes are deployed in a random fashion and form group structures called clusters. Each cluster has a cluster head. The cluster head collects data from the other nodes using the time-division multiple access protocol. The sensor nodes send their data to the cluster head for transmission to the base station node for further processing. The MDC acts as an intermediate node between the cluster head and base station. The MDC, using its dynamic acyclic graph path, collects the data from the cluster head and sends it to base station. This approach is useful for applications including warfighting, intelligent building and medicine. To assess the proposed system, the paper presents a comparison of its performance with other approaches and algorithms that can be used for similar purposes.

  9. Conditional Random Fields for Morphological Analysis of Wireless ECG Signals

    Science.gov (United States)

    Natarajan, Annamalai; Gaiser, Edward; Angarita, Gustavo; Malison, Robert; Ganesan, Deepak; Marlin, Benjamin

    2015-01-01

    Thanks to advances in mobile sensing technologies, it has recently become practical to deploy wireless electrocardiograph sensors for continuous recording of ECG signals. This capability has diverse applications in the study of human health and behavior, but to realize its full potential, new computational tools are required to effectively deal with the uncertainty that results from the noisy and highly non-stationary signals collected using these devices. In this work, we present a novel approach to the problem of extracting the morphological structure of ECG signals based on the use of dynamically structured conditional random field (CRF) models. We apply this framework to the problem of extracting morphological structure from wireless ECG sensor data collected in a lab-based study of habituated cocaine users. Our results show that the proposed CRF-based approach significantly out-performs independent prediction models using the same features, as well as a widely cited open source toolkit. PMID:26726321

  10. Analysis and Algorithms for Imperfect Sensor Deployment and Operations

    Science.gov (United States)

    2016-05-23

    is quite difficult, it can be modeled as a compact integer linear programming problem. However, unlike contemporary research questions, we are posing...Florida, with the goals of (a) illustrating contemporary optimization techniques and challenges to undergraduate students, and (b) encouraging Ph.D...for graduate students. In particular, the PI offered a Multilevel Mathematical Optimization course in the Fall 2015 semester at Clemson. An elective

  11. Availability Issues in Wireless Visual Sensor Networks

    Science.gov (United States)

    Costa, Daniel G.; Silva, Ivanovitch; Guedes, Luiz Affonso; Vasques, Francisco; Portugal, Paulo

    2014-01-01

    Wireless visual sensor networks have been considered for a large set of monitoring applications related with surveillance, tracking and multipurpose visual monitoring. When sensors are deployed over a monitored field, permanent faults may happen during the network lifetime, reducing the monitoring quality or rendering parts or the entire network unavailable. In a different way from scalar sensor networks, camera-enabled sensors collect information following a directional sensing model, which changes the notions of vicinity and redundancy. Moreover, visual source nodes may have different relevancies for the applications, according to the monitoring requirements and cameras' poses. In this paper we discuss the most relevant availability issues related to wireless visual sensor networks, addressing availability evaluation and enhancement. Such discussions are valuable when designing, deploying and managing wireless visual sensor networks, bringing significant contributions to these networks. PMID:24526301

  12. The Long Tail Issue in Large Scale Deployment of Personal Informatics

    DEFF Research Database (Denmark)

    Cuttone, Andrea; Larsen, Jakob Eg

    2014-01-01

    We describe the challenges and the open questions arising during the design and deployment of SensibleJournal, a mobile personal informatics system with interactive visualizations of mobility and social interactions based on data acquired from embedded smartphone sensors. The SensibleJournal system...... was evaluated in a large scale (N=136) mobile sensing field study. We report issues in deployment, limitations in user engagement and uptake, and the challenges in measuring the effect of the system....

  13. When Loved Ones Get Deployed

    Science.gov (United States)

    ... different from hearing about conflicts and violence that break out in the world during our own time. If someone you care about is in the military and is deployed for duty, it's natural to worry about their safety. That's especially true if the person is going ...

  14. SATWG networked quality function deployment

    Science.gov (United States)

    Brown, Don

    1992-01-01

    The initiative of this work is to develop a cooperative process for continual evolution of an integrated, time phased avionics technology plan that involves customers, technologists, developers, and managers. This will be accomplished by demonstrating a computer network technology to augment the Quality Function Deployment (QFD). All results are presented in viewgraph format.

  15. Less is more : data reduction in wireless sensor networks

    NARCIS (Netherlands)

    Masoum, Alireza

    2018-01-01

    Wireless sensor networks are monitoring systems consisting of many small, low-cost and low-power devices called sensor nodes. A large number of sensor nodes are deployed in an environment to monitor a physical phenomenon, execute light processes on collected data, and send either raw data or

  16. Distributed Service Discovery for Heterogeneous Wireless Sensor Networks

    NARCIS (Netherlands)

    Marin Perianu, Raluca; Scholten, Johan; Havinga, Paul J.M.

    Service discovery in heterogeneous Wireless Sensor Networks is a challenging research objective, due to the inherent limitations of sensor nodes and their extensive and dense deployment. The protocols proposed for ad hoc networks are too heavy for sensor environments. This paper presents a

  17. Taste sensor; Mikaku sensor

    Energy Technology Data Exchange (ETDEWEB)

    Toko, K. [Kyushu University, Fukuoka (Japan)

    1998-03-05

    This paper introduces a taste sensor having a lipid/polymer membrane to work as a receptor of taste substances. The paper describes the following matters: this sensor uses a hollow polyvinyl chloride rod filled with KCl aqueous solution, and placed with silver and silver chloride wires, whose cross section is affixed with a lipid/polymer membrane as a lipid membrane electrode to identify taste from seven or eight kinds of response patterns of electric potential output from the lipid/polymer membrane; measurements of different substances presenting acidic taste, salty taste, bitter taste, sweet taste and flavor by using this sensor identified clearly each taste (similar response is shown to a similar taste even if the substances are different); different responses are indicated on different brands of beers; from the result of measuring a great variety of mineral waters, a possibility was suggested that this taste sensor could be used for water quality monitoring sensors; and application of this taste sensor may be expected as a maturation control sensor for Japanese sake (wine) and miso (bean paste) manufacturing. 2 figs., 1 tab.

  18. Post-deployment family violence among UK military personnel.

    Science.gov (United States)

    Kwan, Jamie; Jones, Margaret; Somaini, Greta; Hull, Lisa; Wessely, Simon; Fear, Nicola T; MacManus, Deirdre

    2017-12-19

    Research into violence among military personnel has not differentiated between stranger- and family-directed violence. While military factors (combat exposure and post-deployment mental health problems) are risk factors for general violence, there has been limited research on their impact on violence within the family environment. This study aims to compare the prevalence of family-directed and stranger-directed violence among a deployed sample of UK military personnel and to explore risk factors associated with both family- and stranger-directed violence. This study utilised data from a large cohort study which collected information by questionnaire from a representative sample of randomly selected deployed UK military personnel (n = 6711). The prevalence of family violence immediately following return from deployment was 3.6% and 7.8% for stranger violence. Family violence was significantly associated with having left service, while stranger violence was associated with younger age, male gender, being single, having a history of antisocial behaviour as well as having left service. Deployment in a combat role was significantly associated with both family and stranger violence after adjustment for confounders [adjusted odds ratio (aOR) = 1.92 (1.25-2.94), p = 0.003 and aOR = 1.77 (1.31-2.40), p violence both inside and outside the family environment and should be considered in violence reduction programmes for military personnel. Further research using a validated measurement tool for family violence would improve comparability with other research.

  19. Advanced Deployable Structural Systems for Small Satellites

    Science.gov (United States)

    Belvin, W. Keith; Straubel, Marco; Wilkie, W. Keats; Zander, Martin E.; Fernandez, Juan M.; Hillebrandt, Martin F.

    2016-01-01

    One of the key challenges for small satellites is packaging and reliable deployment of structural booms and arrays used for power, communication, and scientific instruments. The lack of reliable and efficient boom and membrane deployment concepts for small satellites is addressed in this work through a collaborative project between NASA and DLR. The paper provides a state of the art overview on existing spacecraft deployable appendages, the special requirements for small satellites, and initial concepts for deployable booms and arrays needed for various small satellite applications. The goal is to enhance deployable boom predictability and ground testability, develop designs that are tolerant of manufacturing imperfections, and incorporate simple and reliable deployment systems.

  20. Compact, self-contained enhanced-vision system (EVS) sensor simulator

    Science.gov (United States)

    Tiana, Carlo

    2007-04-01

    We describe the model SIM-100 PC-based simulator, for imaging sensors used, or planned for use, in Enhanced Vision System (EVS) applications. Typically housed in a small-form-factor PC, it can be easily integrated into existing out-the-window visual simulators for fixed-wing or rotorcraft, to add realistic sensor imagery to the simulator cockpit. Multiple bands of infrared (short-wave, midwave, extended-midwave and longwave) as well as active millimeter-wave RADAR systems can all be simulated in real time. Various aspects of physical and electronic image formation and processing in the sensor are accurately (and optionally) simulated, including sensor random and fixed pattern noise, dead pixels, blooming, B-C scope transformation (MMWR). The effects of various obscurants (fog, rain, etc.) on the sensor imagery are faithfully represented and can be selected by an operator remotely and in real-time. The images generated by the system are ideally suited for many applications, ranging from sensor development engineering tradeoffs (Field Of View, resolution, etc.), to pilot familiarization and operational training, and certification support. The realistic appearance of the simulated images goes well beyond that of currently deployed systems, and beyond that required by certification authorities; this level of realism will become necessary as operational experience with EVS systems grows.

  1. The Efficacy of Epidemic Algorithms on Detecting Node Replicas in Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Narasimha Shashidhar

    2015-12-01

    Full Text Available A node replication attack against a wireless sensor network involves surreptitious efforts by an adversary to insert duplicate sensor nodes into the network while avoiding detection. Due to the lack of tamper-resistant hardware and the low cost of sensor nodes, launching replication attacks takes little effort to carry out. Naturally, detecting these replica nodes is a very important task and has been studied extensively. In this paper, we propose a novel distributed, randomized sensor duplicate detection algorithm called Discard to detect node replicas in group-deployed wireless sensor networks. Our protocol is an epidemic, self-organizing duplicate detection scheme, which exhibits emergent properties. Epidemic schemes have found diverse applications in distributed computing: load balancing, topology management, audio and video streaming, computing aggregate functions, failure detection, network and resource monitoring, to name a few. To the best of our knowledge, our algorithm is the first attempt at exploring the potential of this paradigm to detect replicas in a wireless sensor network. Through analysis and simulation, we show that our scheme achieves robust replica detection with substantially lower communication, computational and storage requirements than prior schemes in the literature.

  2. Classification of Reactor Facility Operational State Using SPRT Methods with Radiation Sensor Networks

    Energy Technology Data Exchange (ETDEWEB)

    Ramirez Aviles, Camila A. [ORNL; Rao, Nageswara S. [ORNL

    2018-01-01

    We consider the problem of inferring the operational state of a reactor facility by using measurements from a radiation sensor network, which is deployed around the facility’s ventilation stack. The radiation emissions from the stack decay with distance, and the corresponding measurements are inherently random with parameters determined by radiation intensity levels at the sensor locations. We fuse measurements from network sensors to estimate the intensity at the stack, and use this estimate in a one-sided Sequential Probability Ratio Test (SPRT) to infer the on/off state of the reactor facility. We demonstrate the superior performance of this method over conventional majority vote fusers and individual sensors using (i) test measurements from a network of NaI sensors, and (ii) emulated measurements using radioactive effluents collected at a reactor facility stack. We analytically quantify the performance improvements of individual sensors and their networks with adaptive thresholds over those with fixed ones, by using the packing number of the radiation intensity space.

  3. Use of remotely reporting electronic sensors for assessing use of water filters and cookstoves in Rwanda.

    Science.gov (United States)

    Thomas, Evan A; Barstow, Christina K; Rosa, Ghislaine; Majorin, Fiona; Clasen, Thomas

    2013-01-01

    Remotely reporting electronic sensors offer the potential to reduce bias in monitoring use of environmental health interventions. In the context of a five-month randomized controlled trial of household water filters and improved cookstoves in rural Rwanda, we collected data from intervention households on product compliance using (i) monthly surveys and direct observations by community health workers and environmental health officers, and (ii) sensor-equipped filters and cookstoves deployed for about two weeks in each household. The adoption rate interpreted by the sensors varied from the household reporting: 90.5% of households reported primarily using the intervention stove, while the sensors interpreted 73.2% use, and 96.5% of households reported using the intervention filter regularly, while the sensors interpreted no more than 90.2%. The sensor-collected data estimated use to be lower than conventionally collected data both for water filters (approximately 36% less water volume per day) and cookstoves (approximately 40% fewer uses per week). An evaluation of intrahousehold consistency in use suggests that households are not using their filters or stoves on an exclusive basis, and may be both drinking untreated water at times and using other stoves ("stove-stacking"). These results provide additional evidence that surveys and direct observation may exaggerate compliance with household-based environmental interventions.

  4. Supply strategy for SMR deployment

    International Nuclear Information System (INIS)

    Coccagna, A.F.

    2013-01-01

    This document provides a description of Babcock and Wilcox's deployment strategy for the mPower™ Small Modular Reactor from the perspective of Supply Chain and Manufacturing. A desirable future state of readiness is described as one which leverages and revitalizes an existing supply chain and manufacturing infrastructure, as well as leveraging an existing workforce of engineering, construction, and project management employees. B and W's mPower™ SMR value proposition offers many desired design and operating advantages to the SMR market. (author)

  5. Space Surveillance Catalog growth during SBIRS low deployment.

    Science.gov (United States)

    Hoult, C. P.; Wright, R. P.

    The Space Surveillance Catalog is a database of all Resident Space Objects (RSOs) on Earth orbit. It is expected to grow in the future as more RSOs accumulate on orbit. Potentially still more dramatic growth could follow the deployment of the Space Based Infrared System Low Earth Orbit Component (SBTRS Low). SBIRS Low, currently about to enter development, offers the potential to detect and acquire much smaller debris RSOs than can be seen by the current ground-based Space Surveillance Network (SSN). SBIRS Low will host multicolor infrared/visible sensors on each satellite in a proliferated constellation on low Earth orbit, and if appropriately tasked, these sensors could provide significant space surveillance capability. Catalog growth during SBIRS Low deployment was analyzed using a highly aggregated code that numerically integrates the Markov equations governing the state transitions of RSOs from uncataloged to cataloged, and back again. It was assumed that all newly observed debris RSOs will be detected as by-products of routine Catalog maintenance, not including any post breakup searches, and if sufficient sensor resources are available, be acquired into the Catalog. Debris over the entire low to high altitude regime were considered.

  6. NEON's Mobile Deployment Platform: A Resource for Community Research

    Science.gov (United States)

    Sanclements, M.

    2015-12-01

    Here we provide an update on construction and validation of the NEON Mobile Deployment Platforms (MDPs) as well as a description of the infrastructure and sensors available to researchers in the future. The MDPs will provide the means to observe stochastic or spatially important events, gradients, or quantities that cannot be reliably observed using fixed location sampling (e.g. fires and floods). Due to the transient temporal and spatial nature of such events, the MDPs will be designed to accommodate rapid deployment for time periods up to ~ 1 year. Broadly, the MDPs will be comprised of infrastructure and instrumentation capable of functioning individually or in conjunction with one another to support observations of ecological change, as well as education, training and outreach.

  7. Networked Sensor Arrays

    International Nuclear Information System (INIS)

    Tighe, R. J.

    2002-01-01

    A set of independent radiation sensors, coupled with real-time data telemetry, offers the opportunity to run correlation algorithms for the sensor array as well as to incorporate non-radiological data into the system. This may enhance the overall sensitivity of the sensors and provide an opportunity to project the location of a source within the array. In collaboration with Lawrence Livermore National Laboratory (LLNL) and Sandia National Laboratories (SNL), we have conducted field experiments to test a prototype system. Combining the outputs of a set of distributed sensors permits the correlation that the independent sensor outputs. Combined with additional information such as traffic patterns and velocities, this can reduce random/false detections and enhance detection capability. The principle components of such a system include: (1) A set of radiation sensors. These may be of varying type and complexity, including gamma and/or neutron detectors, gross count and spectral-capable sensors, and low to high energy-resolution sensors. (2) A set of non-radiation sensors. These may include sensors such as vehicle presence and imaging sensors. (3) A communications architecture for near real-time telemetry. Depending upon existing infrastructure and bandwidth requirements, this may be a radio or hard-wire based system. (4) A central command console to pole the sensors, correlate their output, and display the data in a meaningful form to the system operator. Both sensitivity and selectivity are important considerations when evaluating the performance of a detection system. Depending on the application, the optimization of sensitivity as well as the rejection of ''nuisance'' radioactive sources may or may not be critical

  8. EarthScope's Transportable Array: Status of the Alaska Deployment and Guide to Resources for Lower48 Deployment

    Science.gov (United States)

    Busby, R. W.; Woodward, R.; Aderhold, K.; Frassetto, A.

    2017-12-01

    The Alaska Transportable Array deployment is completely installed, totaling 280 stations, with 194 new stations and 86 existing stations, 28 of those upgraded with new sensor emplacement. We briefly summarize the deployment of this seismic network, describe the added meteorological instruments and soil temperature gauges, and review our expectations for operation and demobilization. Curation of data from the contiguous Lower-48 States deployment of Transportable Array (>1800 stations, 2004-2015) has continued with the few gaps in real-time data replaced by locally archived files as well as minor adjustments in metadata. We highlight station digests that provide more detail on the components and settings of individual stations, documentation of standard procedures used throughout the deployment and other resources available online. In cooperation with IRIS DMC, a copy of the complete TA archive for the Lower-48 period has been transferred to a local disk to experiment with data access and software workflows that utilize most or all of the seismic timeseries, in contrast to event segments. Assembling such large datasets reliably - from field stations to a well managed data archive to a user's workspace - is complex. Sharing a curated and defined data volume with researchers is a potentially straightforward way to make data intensive analyses less difficult. We note that data collection within the Lower-48 continues with 160 stations of the N4 network operating at increased sample rates (100 sps) as part of the CEUSN, as operational support transitions from NSF to USGS.

  9. An Advanced Temporal Credential-Based Security Scheme with Mutual Authentication and Key Agreement for Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Chun-Ta Li

    2013-07-01

    Full Text Available Wireless sensor networks (WSNs can be quickly and randomly deployed in any harsh and unattended environment and only authorized users are allowed to access reliable sensor nodes in WSNs with the aid of gateways (GWNs. Secure authentication models among the users, the sensor nodes and GWN are important research issues for ensuring communication security and data privacy in WSNs. In 2013, Xue et al. proposed a temporal-credential-based mutual authentication and key agreement scheme for WSNs. However, in this paper, we point out that Xue et al.’s scheme cannot resist stolen-verifier, insider, off-line password guessing, smart card lost problem and many logged-in users’ attacks and these security weaknesses make the scheme inapplicable to practical WSN applications. To tackle these problems, we suggest a simple countermeasure to prevent proposed attacks while the other merits of Xue et al.’s authentication scheme are left unchanged.

  10. An advanced temporal credential-based security scheme with mutual authentication and key agreement for wireless sensor networks.

    Science.gov (United States)

    Li, Chun-Ta; Weng, Chi-Yao; Lee, Cheng-Chi

    2013-07-24

    Wireless sensor networks (WSNs) can be quickly and randomly deployed in any harsh and unattended environment and only authorized users are allowed to access reliable sensor nodes in WSNs with the aid of gateways (GWNs). Secure authentication models among the users, the sensor nodes and GWN are important research issues for ensuring communication security and data privacy in WSNs. In 2013, Xue et al. proposed a temporal-credential-based mutual authentication and key agreement scheme for WSNs. However, in this paper, we point out that Xue et al.'s scheme cannot resist stolen-verifier, insider, off-line password guessing, smart card lost problem and many logged-in users' attacks and these security weaknesses make the scheme inapplicable to practical WSN applications. To tackle these problems, we suggest a simple countermeasure to prevent proposed attacks while the other merits of Xue et al.'s authentication scheme are left unchanged.

  11. A Risk Based Approach to Limit the Effects of Covert Channels for Internet Sensor Data Aggregators for Sensor Privacy

    Science.gov (United States)

    Viecco, Camilo H.; Camp, L. Jean

    Effective defense against Internet threats requires data on global real time network status. Internet sensor networks provide such real time network data. However, an organization that participates in a sensor network risks providing a covert channel to attackers if that organization’s sensor can be identified. While there is benefit for every party when any individual participates in such sensor deployments, there are perverse incentives against individual participation. As a result, Internet sensor networks currently provide limited data. Ensuring anonymity of individual sensors can decrease the risk of participating in a sensor network without limiting data provision.

  12. Time-domain fiber loop ringdown sensor and sensor network

    Science.gov (United States)

    Kaya, Malik

    Optical fibers have been mostly used in fiber optic communications, imaging optics, sensing technology, etc. Fiber optic sensors have gained increasing attention for scientific and structural health monitoring (SHM) applications. In this study, fiber loop ringdown (FLRD) sensors were fabricated for scientific, SHM, and sensor networking applications. FLRD biosensors were fabricated for both bulk refractive index (RI)- and surface RI-based DNA sensing and one type of bacteria sensing. Furthermore, the effect of glucose oxidase (GOD) immobilization at the sensor head on sensor performance was evaluated for both glucose and synthetic urine solutions with glucose concentration between 0.1% and 10%. Detection sensitivities of the glucose sensors were achieved as low as 0.05%. For chemical sensing, heavy water, ranging from 97% to 10%, and several elemental solutions were monitored by using the FLRD chemical sensors. Bulk index-based FLRD sensing showed that trace elements can be detected in deionized water. For physical sensing, water and cracking sensors were fabricated and embedded into concrete. A partially-etched single-mode fiber (SMF) was embedded into a concrete bar for water monitoring while a bare SMF without any treatment was directly embedded into another concrete bar for monitoring cracks. Furthermore, detection sensitivities of water and crack sensors were investigated as 10 ml water and 0.5 mm surface crack width, respectively. Additionally fiber loop ringdown-fiber Bragg grating temperature sensors were developed in the laboratory; two sensor units for water, crack, and temperature sensing were deployed into a concrete cube in a US Department of Energy test bed (Miami, FL). Multi-sensor applications in a real concrete structure were accomplished by testing the six FLRD sensors. As a final stage, a sensor network was assembled by multiplexing two or three FLRD sensors in series and parallel. Additionally, two FLRD sensors were combined in series and

  13. Analytical and Algorithmic Approaches to Determine the Number of Sensor Nodes for Minimum Power Consumption in LWSNs

    Directory of Open Access Journals (Sweden)

    Ali Soner Kilinc

    2017-08-01

    Full Text Available A Linear Wireless Sensor Network (LWSN is a kind of wireless sensor network where the nodes are deployed in a line. Since the sensor nodes are energy restricted, energy efficiency becomes one of the most significant design issues for LWSNs as well as wireless sensor networks. With the proper deployment, the power consumption could be minimized by adjusting the distance between the sensor nodes which is known as hop length. In this paper, analytical and algorithmic approaches are presented to determine the number of hops and sensor nodes for minimum power consumption in a linear wireless sensor network including equidistantly placed sensor nodes.

  14. RSG Deployment Case Testing Results

    Energy Technology Data Exchange (ETDEWEB)

    Owsley, Stanley L.; Dodson, Michael G.; Hatchell, Brian K.; Seim, Thomas A.; Alexander, David L.; Hawthorne, Woodrow T.

    2005-09-01

    The RSG deployment case design is centered on taking the RSG system and producing a transport case that houses the RSG in a safe and controlled manner for transport. The transport case was driven by two conflicting constraints, first that the case be as light as possible, and second that it meet a stringent list of Military Specified requirements. The design team worked to extract every bit of weight from the design while striving to meet the rigorous Mil-Spec constraints. In the end compromises were made primarily on the specification side to control the overall weight of the transport case. This report outlines the case testing results.

  15. Multi-Source Energy Harvesting for Wireless Sensor Nodes.

    OpenAIRE

    Kang, Kai

    2012-01-01

    The past few years have seen an increasing interest in the development of wireless sensor networks. But the unsatisfactory or limited available energy source is one of the major bottlenecks which are limiting the wireless sensor technology from mass deployment. Ambient energy harvesting is the most promising solution towards autonomous sensor nodes by providing low cost, permanent, and maintenance-free energy source to wireless sensor nodes. In this paper, we first invested available energy s...

  16. Wireless Sensor Network for Forest Fire Detection 2

    OpenAIRE

    João Gilberto Fernandes Gonçalves Teixeira

    2017-01-01

    The main purpose for this project is the development of a semi-autonomous wireless sensor network for fire detection in remote territory. Making use of the IEEE 802.15.4 standard, a wireless standard for low-power, low-rate wireless sensor networks, a real sensor network and web application will be developed and deployed with the ability to monitor sensor data, detect a fire occurrence and generate early fire alerts.

  17. Supporting Knowledge Transfer in IS Deployment Projects

    Science.gov (United States)

    Schönström, Mikael

    To deploy new information systems is an expensive and complex task, and does seldom result in successful usage where the system adds strategic value to the firm (e.g. Sharma et al. 2003). It has been argued that innovation diffusion is a knowledge integration problem (Newell et al. 2000). Knowledge about business processes, deployment processes, information systems and technology are needed in a large-scale deployment of a corporate IS. These deployments can therefore to a large extent be argued to be a knowledge management (KM) problem. An effective deployment requires that knowledge about the system is effectively transferred to the target organization (Ko et al. 2005).

  18. An Energy Oriented Model and Simulator for Wireless Sensor etworks

    African Journals Online (AJOL)

    Nafiisah

    Wireless Sensor Network, Energy Modeling, Simulation, Energy. Efficiency ..... xMBCR: This scheme is based on the MBCR strategy, but improves the battery ... Moreover WSNs require large scale deployment (smart dusts) in remote and.

  19. Ambient Sensors

    NARCIS (Netherlands)

    Börner, Dirk; Specht, Marcus

    2014-01-01

    This software sketches comprise two custom-built ambient sensors, i.e. a noise and a movement sensor. Both sensors measure an ambient value and process the values to a color gradient (green > yellow > red). The sensors were built using the Processing 1.5.1 development environment. Available under

  20. Visualization and Analysis of Wireless Sensor Network Data for Smart Civil Structure Applications Based On Spatial Correlation Technique

    Science.gov (United States)

    Chowdhry, Bhawani Shankar; White, Neil M.; Jeswani, Jai Kumar; Dayo, Khalil; Rathi, Manorma

    2009-07-01

    Disasters affecting infrastructure, such as the 2001 earthquakes in India, 2005 in Pakistan, 2008 in China and the 2004 tsunami in Asia, provide a common need for intelligent buildings and smart civil structures. Now, imagine massive reductions in time to get the infrastructure working again, realtime information on damage to buildings, massive reductions in cost and time to certify that structures are undamaged and can still be operated, reductions in the number of structures to be rebuilt (if they are known not to be damaged). Achieving these ideas would lead to huge, quantifiable, long-term savings to government and industry. Wireless sensor networks (WSNs) can be deployed in buildings to make any civil structure both smart and intelligent. WSNs have recently gained much attention in both public and research communities because they are expected to bring a new paradigm to the interaction between humans, environment, and machines. This paper presents the deployment of WSN nodes in the Top Quality Centralized Instrumentation Centre (TQCIC). We created an ad hoc networking application to collect real-time data sensed from the nodes that were randomly distributed throughout the building. If the sensors are relocated, then the application automatically reconfigures itself in the light of the new routing topology. WSNs are event-based systems that rely on the collective effort of several micro-sensor nodes, which are continuously observing a physical phenomenon. WSN applications require spatially dense sensor deployment in order to achieve satisfactory coverage. The degree of spatial correlation increases with the decreasing inter-node separation. Energy consumption is reduced dramatically by having only those sensor nodes with unique readings transmit their data. We report on an algorithm based on a spatial correlation technique that assures high QoS (in terms of SNR) of the network as well as proper utilization of energy, by suppressing redundant data transmission

  1. Mathematical theories of distributed sensor networks

    CERN Document Server

    Iyengar, Sitharama S; Balakrishnan, N

    2014-01-01

    Mathematical Theory of Distributed Sensor Networks demonstrates how mathematical theories can be used to provide distributed sensor modeling and to solve important problems such as coverage hole detection and repair. The book introduces the mathematical and computational structure by discussing what they are, their applications and how they differ from traditional systems. The text also explains how mathematics are utilized to provide efficient techniques implementing effective coverage, deployment, transmission, data processing, signal processing, and data protection within distributed sensor networks. Finally, the authors discuss some important challenges facing mathematics to get more incite to the multidisciplinary area of distributed sensor networks.

  2. Image-based environmental monitoring sensor application using an embedded wireless sensor network.

    Science.gov (United States)

    Paek, Jeongyeup; Hicks, John; Coe, Sharon; Govindan, Ramesh

    2014-08-28

    This article discusses the experiences from the development and deployment of two image-based environmental monitoring sensor applications using an embedded wireless sensor network. Our system uses low-power image sensors and the Tenet general purpose sensing system for tiered embedded wireless sensor networks. It leverages Tenet's built-in support for reliable delivery of high rate sensing data, scalability and its flexible scripting language, which enables mote-side image compression and the ease of deployment. Our first deployment of a pitfall trap monitoring application at the James San Cannot Mountain Reserve provided us with insights and lessons learned into the deployment of and compression schemes for these embedded wireless imaging systems. Our three month-long deployment of a bird nest monitoring application resulted in over 100,000 images collected from a 19-camera node network deployed over an area of 0.05 square miles, despite highly variable environmental conditions. Our biologists found the on-line, near-real-time access to images to be useful for obtaining data on answering their biological questions.

  3. Image-Based Environmental Monitoring Sensor Application Using an Embedded Wireless Sensor Network

    Directory of Open Access Journals (Sweden)

    Jeongyeup Paek

    2014-08-01

    Full Text Available This article discusses the experiences from the development and deployment of two image-based environmental monitoring sensor applications using an embedded wireless sensor network. Our system uses low-power image sensors and the Tenet general purpose sensing system for tiered embedded wireless sensor networks. It leverages Tenet’s built-in support for reliable delivery of high rate sensing data, scalability and its flexible scripting language, which enables mote-side image compression and the ease of deployment. Our first deployment of a pitfall trap monitoring application at the James San Jacinto Mountain Reserve provided us with insights and lessons learned into the deployment of and compression schemes for these embedded wireless imaging systems. Our three month-long deployment of a bird nest monitoring application resulted in over 100,000 images collected from a 19-camera node network deployed over an area of 0.05 square miles, despite highly variable environmental conditions. Our biologists found the on-line, near-real-time access to images to be useful for obtaining data on answering their biological questions.

  4. A Review on State of Art Variants of LEACH Protocol for Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Yuvaraj P.

    2015-03-01

    Full Text Available Recent advances in wireless communication lead to many improvements in application specific wireless sensor network (WSN deployment. Sensing different data from different environments is essential to monitor and control the situations. For instance, it is very important to sense the forest fire as early as possible to control the upshot. So efficient and timely gathering of the data from a network of small sensor nodes is necessary. In WSN, the small sized sensor nodes are working with very small batteries with limited energy. Since those are randomly deployed over a wide area, replacement of battery or recharging is not feasible. So, for getting prolonged life time of WSN, energy efficient operation is the key factor. Among many protocols proposed for enhancing the life time of WSN, the clustering based hierarchical protocols are popular and gaining the attention of researchers because of their high energy efficiency. Low Energy Adaptive Clustering Hierarchy (LEACH is energy efficient hierarchical, clustering based protocol. It is considered as the base of many hierarchical clustering protocols. In this paper, some of the recent tailored protocols proposed to strengthen LEACH are examined.

  5. Detection of Intelligent Intruders in Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Yun Wang

    2016-01-01

    Full Text Available Most of the existing research works on the intrusion detection problem in a wireless sensor network (WSN assume linear or random mobility patterns in abstracting intruders’ models in traversing the WSN field. However, in real-life WSN applications, an intruder is usually an intelligent mobile robot with environment learning and detection avoidance capability (i.e., the capability to avoid surrounding sensors. Due to this, the literature results based on the linear or random mobility models may not be applied to the real-life WSN design and deployment for efficient and effective intrusion detection in practice. This motivates us to investigate the impact of intruder’s intelligence on the intrusion detection problem in a WSN for various applications. To be specific, we propose two intrusion algorithms, the pinball and flood-fill algorithms, to mimic the intelligent motion and behaviors of a mobile intruder in detecting and circumventing nearby sensors for detection avoidance while heading for its destination. The two proposed algorithms are integrated into a WSN framework for intrusion detection analysis in various circumstances. Monte Carlo simulations are conducted, and the results indicate that: (1 the performance of a WSN drastically changes as a result of the intruder’s intelligence in avoiding sensor detections and intrusion algorithms; (2 network parameters, including node density, sensing range and communication range, play a crucial part in the effectiveness of the intruder’s intrusion algorithms; and (3 it is imperative to integrate intruder’s intelligence in the WSN research for intruder detection problems under various application circumstances.

  6. A Hybrid Optimized Weighted Minimum Spanning Tree for the Shortest Intrapath Selection in Wireless Sensor Network

    Directory of Open Access Journals (Sweden)

    Matheswaran Saravanan

    2014-01-01

    Full Text Available Wireless sensor network (WSN consists of sensor nodes that need energy efficient routing techniques as they have limited battery power, computing, and storage resources. WSN routing protocols should enable reliable multihop communication with energy constraints. Clustering is an effective way to reduce overheads and when this is aided by effective resource allocation, it results in reduced energy consumption. In this work, a novel hybrid evolutionary algorithm called Bee Algorithm-Simulated Annealing Weighted Minimal Spanning Tree (BASA-WMST routing is proposed in which randomly deployed sensor nodes are split into the best possible number of independent clusters with cluster head and optimal route. The former gathers data from sensors belonging to the cluster, forwarding them to the sink. The shortest intrapath selection for the cluster is selected using Weighted Minimum Spanning Tree (WMST. The proposed algorithm computes the distance-based Minimum Spanning Tree (MST of the weighted graph for the multihop network. The weights are dynamically changed based on the energy level of each sensor during route selection and optimized using the proposed bee algorithm simulated annealing algorithm.

  7. Jamming Attack in Wireless Sensor Network: From Time to Space

    Science.gov (United States)

    Sun, Yanqiang; Wang, Xiaodong; Zhou, Xingming

    Classical jamming attack models in the time domain have been proposed, such as constant jammer, random jammer, and reactive jammer. In this letter, we consider a new problem: given k jammers, how does the attacker minimize the pair-wise connectivity among the nodes in a Wireless Sensor Network (WSN)? We call this problem k-Jammer Deployment Problem (k-JDP). To the best of our knowledge, this is the first attempt at considering the position-critical jamming attack against wireless sensor network. We mainly make three contributions. First, we prove that the decision version of k-JDP is NP-complete even in the ideal situation where the attacker has full knowledge of the topology information of sensor network. Second, we propose a mathematical formulation based on Integer Programming (IP) model which yields an optimal solution. Third, we present a heuristic algorithm HAJDP, and compare it with the IP model. Numerical results show that our heuristic algorithm is computationally efficient.

  8. Means for maintaining a fixed relative orientation of two sensors

    International Nuclear Information System (INIS)

    Jubinski, P.

    1987-01-01

    A sensor module adapted for use in a seismic cable is described comprising: an enclosed housing; a volume of fluid within the housing; a first sensor unit having a specific gravity less than the specific gravity of the fluid and deployed within the housing so that the first sensor unit floats at the top of the fluid as the orientation of the housing changes; a second sensor unit having a specific gravity greater than the specific gravity of the fluid and deployed within the housing so that the second sensor unit remains at the bottom of the fluid as the orientation of the housing changes; a first and second flexible tether securing the first and second sensor units, respectively, to opposite ends of the housing, the tethers including signal conductors for coupling signal from the sensor units to the exterior of the housing

  9. Multi-Sensor Approach for the Monitoring of Halitosis Treatment via Lactobacillus brevis (CD2—Containing Lozenges—A Randomized, Double-Blind Placebo-Controlled Clinical Trial

    Directory of Open Access Journals (Sweden)

    Enrico Marchetti

    2015-08-01

    Full Text Available The aim of this randomized clinical trial was to evaluate whether a recently described multi-sensor approach called BIONOTE® is accurate enough to verify the efficacy of treatment of patients with halitosis. A treatment with Lactobacillus brevis (CD2–containing lozenges, compared with placebo was tested. The BIONOTE® was compared with traditional techniques used to detect halitosis: OralChroma™ and two calibrated odor judges enrolled for the organoleptic assessments. Twenty patients (10 treated and 10 placebo, suffering from active phase halitosis were included in the study. Treatment consisted of Lactobacillus brevis (CD2—containing lozenges or placebo, 4 tablets/day for 14 days. t0 was before the beginning of the study; t1 was day 7 and t2 was day 14. The effectiveness of treatment was assessed through: (1 Rosenberg score; (2 Winkel tongue coating index (WTCI anterior and posterior; (2 OralChroma™; (3 the new developed multi-sensor approach, called BIONOTE® (test technique. Only the WTCI anterior revealed statistically significant changes between t0 and t2 data (p = 0.014 in the treated group. Except for the WTCI anterior, all diagnostic methods revealed the lack of effectiveness for halitosis of a 14-days treatment with Lactobacillus brevis (CD2–containing lozenges. The BIONOTE® multisensor system seems accurate in addition to OralChroma™ to assess the initial condition of halitosis and its mitigation during treatment.

  10. Cognitive networks applications and deployments

    CERN Document Server

    Lloret Mauri, Jaime; Rawat, Danda B; Perez, Javier Manuel Aguiar

    2014-01-01

    INTRODUCTIONEfficient Spectrum Management: Challenges and Solutions; Tarek M. Salem, Sherine M. Abdel-Kader, Salah M. Abdel-MaGeid, and Mohamed ZakiA Survey on Joint Routing and Dynamic spectrum Access in Cognitive Radio Networks; Xianzhong Xie, Helin Yang, and Athanasios V. VasilakosNeighbor Discovery for Cognitive Radio Networks; Athar Ali Khan, Mubashir Husain Rehmani, and Yasir SaleemSPECTRUM SENSINGTime-Domain Cognitive Sensor Networking; Stefano Busanelli, Gianluigi Ferrari, Alessandro Colazzo, and Jean-Michel DricotSpectrum Sensing in Cognitive Wireless Networks; Danda B. Rawat and Chan

  11. Reintegration Difficulty of Military Couples Following Deployment

    Science.gov (United States)

    2016-07-01

    Response rate for Wave 8 = 88% Our final sample contained 554 men and 556 women (n = 554 cross- sex couples, 1 same- sex couple). Individuals were...story in the Killeen Daily Herald (10 April 2016) http://kdhnews.com/news/local/ kids -deployments-when-a-parent-deploys-children-face- tough...years old), and (c) “Me getting sick and having to go to sick call.” (deployed Army husband, 25 years old). Sex and fidelity. Comments fell into

  12. Security Support in Continuous Deployment Pipeline

    DEFF Research Database (Denmark)

    Ullah, Faheem; Raft, Adam Johannes; Shahin, Mojtaba

    2017-01-01

    Continuous Deployment (CD) has emerged as a new practice in the software industry to continuously and automatically deploy software changes into production. Continuous Deployment Pipeline (CDP) supports CD practice by transferring the changes from the repository to production. Since most of the CDP...... penetration tools. Our findings indicate that the applied tactics improve the security of the major components (i.e., repository, continuous integration server, main server) of a CDP by controlling access to the components and establishing secure connections....

  13. Low Mass Aeroshell Deployment Mechanism, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Cornerstone Research Group Inc. (CRG) will develop new shape memory polymer (SMP) deployment mechanisms for actuating thermal protective systems (TPS) panels to...

  14. Low Mass Aeroshell Deployment Mechanism, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — Cornerstone Research Group Inc. (CRG) will develop new shape memory polymer (SMP) deployment mechanisms for actuating thermal protection system (TPS) panels to...

  15. The MAGCLOUD wireless sensor network

    OpenAIRE

    Cuartero Moya, Narciso; Quintana Alcaraz, Sergio

    2011-01-01

    Initially, the aim of this project consisted in manufacturing some nodes for a wireless sensor network by hand. If this document concludes that they can be properly produced in the EETAC lab, the cost of a future large deployment using raw components would be much lower than in the case of acquiring the genuine factory assembled hardware. Also, the future students involved in the process could learn many useful advanced techniques along the way. The project ended sowing a future WSN con...

  16. Plant stress analysis technology deployment

    Energy Technology Data Exchange (ETDEWEB)

    Ebadian, M.A.

    1998-01-01

    Monitoring vegetation is an active area of laser-induced fluorescence imaging (LIFI) research. The Hemispheric Center for Environmental Technology (HCET) at Florida International University (FIU) is assisting in the transfer of the LIFI technology to the agricultural private sector through a market survey. The market survey will help identify the key eco-agricultural issues of the nations that could benefit from the use of sensor technologies developed by the Office of Science and Technology (OST). The principal region of interest is the Western Hemisphere, particularly, the rapidly growing countries of Latin America and the Caribbean. The analysis of needs will assure that the focus of present and future research will center on economically important issues facing both hemispheres. The application of the technology will be useful to the agriculture industry for airborne crop analysis as well as in the detection and characterization of contaminated sites by monitoring vegetation. LIFI airborne and close-proximity systems will be evaluated as stand-alone technologies and additions to existing sensor technologies that have been used to monitor crops in the field and in storage.

  17. Towards Interoperable IoT Deployments inSmart Cities - How project VITAL enables smart, secure and cost- effective cities

    OpenAIRE

    Schiele , Gregor; Soldatos , John; Mitton , Nathalie

    2014-01-01

    International audience; IoT-based deployments in smart cities raise several challenges, especially in terms of interoperability. In this paper, we illustrate semantic interoperability solutions for IoT systems. Based on these solutions, we describe how the FP7 VITAL project aims to bridge numerous silo IoT deployments in smart cities through repurposing and reusing sensors and data streams across multiple applications without carelessly compromising citizens’ security and privacy. This approa...

  18. Autonomous Sensors for Large Scale Data Collection

    Science.gov (United States)

    Noto, J.; Kerr, R.; Riccobono, J.; Kapali, S.; Migliozzi, M. A.; Goenka, C.

    2017-12-01

    Presented here is a novel implementation of a "Doppler imager" which remotely measures winds and temperatures of the neutral background atmosphere at ionospheric altitudes of 87-300Km and possibly above. Incorporating both recent optical manufacturing developments, modern network awareness and the application of machine learning techniques for intelligent self-monitoring and data classification. This system achieves cost savings in manufacturing, deployment and lifetime operating costs. Deployed in both ground and space-based modalities, this cost-disruptive technology will allow computer models of, ionospheric variability and other space weather models to operate with higher precision. Other sensors can be folded into the data collection and analysis architecture easily creating autonomous virtual observatories. A prototype version of this sensor has recently been deployed in Trivandrum India for the Indian Government. This Doppler imager is capable of operation, even within the restricted CubeSat environment. The CubeSat bus offers a very challenging environment, even for small instruments. The lack of SWaP and the challenging thermal environment demand development of a new generation of instruments; the Doppler imager presented is well suited to this environment. Concurrent with this CubeSat development is the development and construction of ground based arrays of inexpensive sensors using the proposed technology. This instrument could be flown inexpensively on one or more CubeSats to provide valuable data to space weather forecasters and ionospheric scientists. Arrays of magnetometers have been deployed for the last 20 years [Alabi, 2005]. Other examples of ground based arrays include an array of white-light all sky imagers (THEMIS) deployed across Canada [Donovan et al., 2006], oceans sensors on buoys [McPhaden et al., 2010], and arrays of seismic sensors [Schweitzer et al., 2002]. A comparable array of Doppler imagers can be constructed and deployed on the

  19. Attention Sensor

    NARCIS (Netherlands)

    Börner, Dirk; Kalz, Marco; Specht, Marcus

    2014-01-01

    This software sketch was used in the context of an experiment for the PhD project “Ambient Learning Displays”. The sketch comprises a custom-built attention sensor. The sensor measured (during the experiment) whether a participant looked at and thus attended a public display. The sensor was built

  20. Evaluation of Methods for In-Situ Calibration of Field-Deployable Microphone Phased Arrays

    Science.gov (United States)

    Humphreys, William M.; Lockard, David P.; Khorrami, Mehdi R.; Culliton, William G.; McSwain, Robert G.

    2017-01-01

    Current field-deployable microphone phased arrays for aeroacoustic flight testing require the placement of hundreds of individual sensors over a large area. Depending on the duration of the test campaign, the microphones may be required to stay deployed at the testing site for weeks or even months. This presents a challenge in regards to tracking the response (i.e., sensitivity) of the individual sensors as a function of time in order to evaluate the health of the array. To address this challenge, two different methods for in-situ tracking of microphone responses are described. The first relies on the use of an aerial sound source attached as a payload on a hovering small Unmanned Aerial System (sUAS) vehicle. The second relies on the use of individually excited ground-based sound sources strategically placed throughout the array pattern. Testing of the two methods was performed in microphone array deployments conducted at Fort A.P. Hill in 2015 and at Edwards Air Force Base in 2016. The results indicate that the drift in individual sensor responses can be tracked reasonably well using both methods. Thus, in-situ response tracking methods are useful as a diagnostic tool for monitoring the health of a phased array during long duration deployments.

  1. Concurrent engineering: effective deployment strategies

    Directory of Open Access Journals (Sweden)

    Unny Menon

    1996-12-01

    Full Text Available This paper provides a comprehensive insight into current trends and developments in Concurrent Engineering for integrated development of products and processes with the goal of completing the entire cycle in a shorter time, at lower overall cost and with fewer engineering design changes after product release. The evolution and definition of Concurrent Engineering are addressed first, followed by a concise review of the following elements of the concurrent engineering approach to product development: Concept Development: The Front-End Process, identifying Customer Needs and Quality Function Deployment, Establishing Product Specifications, Concept Selection, Product Architecture, Design for Manufacturing, Effective Rapid Prototyping, and The Economics of Product Development. An outline of a computer-based tutorial developed by the authors and other graduate students funded by NASA ( accessible via the world-wide-web . is provided in this paper. A brief discussion of teamwork for successful concurrent engineering is included, t'ase histories of concurrent engineering implementation at North American and European companies are outlined with references to textbooks authored by Professor Menon and other writers. A comprehensive bibliography on concurrent engineering is included in the paper.

  2. Statistical Analysis of the Random Telegraph Noise in a 1.1 μm Pixel, 8.3 MP CMOS Image Sensor Using On-Chip Time Constant Extraction Method.

    Science.gov (United States)

    Chao, Calvin Yi-Ping; Tu, Honyih; Wu, Thomas Meng-Hsiu; Chou, Kuo-Yu; Yeh, Shang-Fu; Yin, Chin; Lee, Chih-Lin

    2017-11-23

    A study of the random telegraph noise (RTN) of a 1.1 μm pitch, 8.3 Mpixel CMOS image sensor (CIS) fabricated in a 45 nm backside-illumination (BSI) technology is presented in this paper. A noise decomposition scheme is used to pinpoint the noise source. The long tail of the random noise (RN) distribution is directly linked to the RTN from the pixel source follower (SF). The full 8.3 Mpixels are classified into four categories according to the observed RTN histogram peaks. A theoretical formula describing the RTN as a function of the time difference between the two phases of the correlated double sampling (CDS) is derived and validated by measured data. An on-chip time constant extraction method is developed and applied to the RTN analysis. The effects of readout circuit bandwidth on the settling ratios of the RTN histograms are investigated and successfully accounted for in a simulation using a RTN behavior model.

  3. IBE-Lite: a lightweight identity-based cryptography for body sensor networks.

    Science.gov (United States)

    Tan, Chiu C; Wang, Haodong; Zhong, Sheng; Li, Qun

    2009-11-01

    A body sensor network (BSN) is a network of sensors deployed on a person's body for health care monitoring. Since the sensors collect personal medical data, security and privacy are important components in a BSN. In this paper, we developed IBE-Lite, a lightweight identity-based encryption suitable for sensors in a BSN. We present protocols based on IBE-Lite that balance security and privacy with accessibility and perform evaluation using experiments conducted on commercially available sensors.

  4. CoCMA: Energy-Efficient Coverage Control in Cluster-Based Wireless Sensor Networks Using a Memetic Algorithm

    Directory of Open Access Journals (Sweden)

    Yung-Chung Wang

    2009-06-01

    Full Text Available Deployment of wireless sensor networks (WSNs has drawn much attention in recent years. Given the limited energy for sensor nodes, it is critical to implement WSNs with energy efficiency designs. Sensing coverage in networks, on the other hand, may degrade gradually over time after WSNs are activated. For mission-critical applications, therefore, energy-efficient coverage control should be taken into consideration to support the quality of service (QoS of WSNs. Usually, coverage-controlling strategies present some challenging problems: (1 resolving the conflicts while determining which nodes should be turned off to conserve energy; (2 designing an optimal wake-up scheme that avoids awakening more nodes than necessary. In this paper, we implement an energy-efficient coverage control in cluster-based WSNs using a Memetic Algorithm (MA-based approach, entitled CoCMA, to resolve the challenging problems. The CoCMA contains two optimization strategies: a MA-based schedule for sensor nodes and a wake-up scheme, which are responsible to prolong the network lifetime while maintaining coverage preservation. The MA-based schedule is applied to a given WSN to avoid unnecessary energy consumption caused by the redundant nodes. During the network operation, the wake-up scheme awakens sleeping sensor nodes to recover coverage hole caused by dead nodes. The performance evaluation of the proposed CoCMA was conducted on a cluster-based WSN (CWSN under either a random or a uniform deployment of sensor nodes. Simulation results show that the performance yielded by the combination of MA and wake-up scheme is better than that in some existing approaches. Furthermore, CoCMA is able to activate fewer sensor nodes to monitor the required sensing area.

  5. Neural network-based sensor signal accelerator.

    Energy Technology Data Exchange (ETDEWEB)

    Vogt, M. C.

    2000-10-16

    A strategy has been developed to computationally accelerate the response time of a generic electronic sensor. The strategy can be deployed as an algorithm in a control system or as a physical interface (on an embedded microcontroller) between a slower responding external sensor and a higher-speed control system. Optional code implementations are available to adjust algorithm performance when computational capability is limited. In one option, the actual sensor signal can be sampled at the slower rate with adaptive linear neural networks predicting the sensor's future output and interpolating intermediate synthetic output values. In another option, a synchronized collection of predictors sequentially controls the corresponding synthetic output voltage. Error is adaptively corrected in both options. The core strategy has been demonstrated with automotive oxygen sensor data. A prototype interface device is under construction. The response speed increase afforded by this strategy could greatly offset the cost of developing a replacement sensor with a faster physical response time.

  6. Optical seismic sensor systems and methods

    Science.gov (United States)

    Beal, A. Craig; Cummings, Malcolm E.; Zavriyev, Anton; Christensen, Caleb A.; Lee, Keun

    2015-12-08

    Disclosed is an optical seismic sensor system for measuring seismic events in a geological formation, including a surface unit for generating and processing an optical signal, and a sensor device optically connected to the surface unit for receiving the optical signal over an optical conduit. The sensor device includes at least one sensor head for sensing a seismic disturbance from at least one direction during a deployment of the sensor device within a borehole of the geological formation. The sensor head includes a frame and a reference mass attached to the frame via at least one flexure, such that movement of the reference mass relative to the frame is constrained to a single predetermined path.

  7. Reconfiguration of sustainable thermoelectric generation using wireless sensor network

    DEFF Research Database (Denmark)

    Chen, Min

    2014-01-01

    wireless sensor networks (WSNs), where remotely deployed temperature and voltage sensors as well as latching relays can be organized as a whole to intelligently identify and execute the optimal interconnection of TEM strings. A reconfigurable TEM array with a WSN controller and a maximum power point...

  8. Wireless sensor network for irrigation application in cotton

    Science.gov (United States)

    A wireless sensor network was deployed in a cotton field to monitor soil water status for irrigation. The network included two systems, a Decagon system and a microcontroller-based system. The Decagon system consists of soil volumetric water-content sensors, wireless data loggers, and a central data...

  9. Performance analysis of data retrieval in wireless sensor networks

    NARCIS (Netherlands)

    Mitici, M.A.

    2015-01-01

    Wireless sensor networks are currently revolutionizing the way we live, work, and interact with the surrounding environment. Due to their ease of deployment, cost effectiveness and versatile functionality, sensors are employed in a wide range of areas such as environmental monitoring, surveillance

  10. Optimal task scheduling policy in energy harvesting wireless sensor networks

    NARCIS (Netherlands)

    Rao, Vijay S.; Prasad, R. Venkatesha; Niemegeers, Ignas G M M

    2015-01-01

    Ambient energy harvesting for Wireless Sensor Networks (WSNs) is being pitched as a promising solution for long-lasting deployments in various WSN applications. However, the sensor nodes most often do not have enough energy to handle application, network and house-keeping tasks because amount of

  11. Mobile platform sampling for designing environmental sensor networks.

    Science.gov (United States)

    Budi, Setia; de Souza, Paulo; Timms, Greg; Susanto, Ferry; Malhotra, Vishv; Turner, Paul

    2018-02-09

    This paper proposes a method to design the deployment of sensor nodes in a new region where historical data is not available. A number of mobile platforms are simulated to build initial knowledge of the region. Further, an evolutionary algorithm is employed to find the optimum placement of a given number of sensor nodes that best represents the region of interest.

  12. Reintegration Difficulty of Military Couples Following Deployment

    Science.gov (United States)

    2017-07-01

    reintegration. Communication and Generalized Anxiety The emotional cycle of deployment model provides a descrip- tive framework for understanding the...counseling. Thus, communication can have a reciprocal influence on the very appraisals and emotions that motivate interaction in the first place. Communication...of service members back into family life after deployment can be extremely challenging for military couples. Understanding the factors that

  13. 5-Beam ADCP Deployment Strategy Considerations

    Science.gov (United States)

    Moore, T.; Savidge, D. K.; Gargett, A.

    2016-02-01

    With the increasing availability of 5 beam ADCPs and expanding opportunities for their deployment within both observatory and dedicated process study settings, refinements in deployment strategies are needed.Measuring vertical velocities directly with a vertically oriented acoustic beam requires that the instrument be stably mounted and leveled within fractions of a degree. Leveled shallow water deployments to date have utilized divers to jet pipes into the sand for stability, manually mount the instruments on the pipes, and level them. Leveling has been guided by the deployed instrument's pitch and roll output, available in real-time because of the observatory settings in which the deployments occurred. To expand the range of feasible deployments to deeper, perhaps non-real-time capable settings, alternatives to diver deployment and leveling must be considered. To determine stability requirements, mooring motion (heading, pitch and roll) has been sampled at 1Hz by gimballed ADCPs at a range of instrument deployment depths, and in shrouded and unshrouded cages. Conditions under which ADCP cages resting on the bottom experience significant shifts in tilt, roll or heading are assessed using co-located wind and wave measurements. The accuracy of estimating vertical velocities using all five beams relative to a well leveled vertical single beam is assessed from archived high frequency five beam data, to explore whether easing the leveling requirement is feasible.

  14. Renewable Energy: Policy Considerations for Deploying Renewables

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2011-07-01

    This information paper accompanies the IEA publication Deploying Renewables 2011: Best and Future Policy Practice (IEA, 2011a). It provides more detailed data and analysis on policies for Deploying Renewables, and is intended to complement the main publication. It provides an account of the strategic drivers underpinning renewable energy (RE) technology deployment (energy security, economic development and environment protection) and assesses RE technologies with respect to these drivers, including an estimate of GHG emissions reductions due to RE technologies. The paper also explores the different barriers to deploying renewables at a given stage of market maturity and discusses what tools policy makers can avail of to succeed in removing deployment barriers. An additional topical highlight explores the challenges associated with accelerating the diffusion of RE technologies in developing countries.

  15. Conceptual design of EAST multi-purpose maintenance deployer system

    Energy Technology Data Exchange (ETDEWEB)

    Pan, Hongtao [Institute of Plasma Physics, Chinese Academy of Sciences, 350 Shushanhu Rd, Hefei, Anhui (China); University of Science and Technology of China, Hefei, Anhui 230022 (China); He, Kaihui, E-mail: hekh@iterchina.cn [China International Nuclear Fusion Energy Program Execution Center, Beijing 100862 (China); Cheng, Yong [Institute of Plasma Physics, Chinese Academy of Sciences, 350 Shushanhu Rd, Hefei, Anhui (China); Song, Yuntao [Institute of Plasma Physics, Chinese Academy of Sciences, 350 Shushanhu Rd, Hefei, Anhui (China); University of Science and Technology of China, Hefei, Anhui 230022 (China); Yang, Yang [Institute of Plasma Physics, Chinese Academy of Sciences, 350 Shushanhu Rd, Hefei, Anhui (China); Villedieu, Eric [CEA-IRFM, F-13108 Saint-Paul-Lez-Durance (France); Shi, Shanshuang; Yang, Songzhu [Institute of Plasma Physics, Chinese Academy of Sciences, 350 Shushanhu Rd, Hefei, Anhui (China)

    2017-05-15

    Highlights: • A redundant 11-DOF articulated robot for EAST in-vessel maintenance is presented. • A new modular joint developed to optimize the yaw joint actuator for the robot is described. • A 3-DOF gripper integrated with cameras and torque sensor is developed. - Abstract: EAST multi-purpose maintenance deployer (EMMD) system, being collaboratively developed by ASIPP and CEA-IRFM, is built as upgrades for EAMA. Updated kinematics parameters such as DOF distribution and joint angle for EMMD robot are performed and verified in a simulation platform. A new modular joint has been developed to optimize the yaw joint actuator for easy assembly and flexibility reduction. A 3-DOF gripper with cameras and torque sensor has been designed to provide inspection and dexterous handling of small fragments inside the EAST chamber. A conceptual upgrade for EAMA-CASK has been developed for the purpose of protecting the end-effector's sensors which do not have temperature-resistant qualification. The high temperature and vacuum compatible solutions and validation experiments have been presented in this paper.

  16. Conceptual design of EAST multi-purpose maintenance deployer system

    International Nuclear Information System (INIS)

    Pan, Hongtao; He, Kaihui; Cheng, Yong; Song, Yuntao; Yang, Yang; Villedieu, Eric; Shi, Shanshuang; Yang, Songzhu

    2017-01-01

    Highlights: • A redundant 11-DOF articulated robot for EAST in-vessel maintenance is presented. • A new modular joint developed to optimize the yaw joint actuator for the robot is described. • A 3-DOF gripper integrated with cameras and torque sensor is developed. - Abstract: EAST multi-purpose maintenance deployer (EMMD) system, being collaboratively developed by ASIPP and CEA-IRFM, is built as upgrades for EAMA. Updated kinematics parameters such as DOF distribution and joint angle for EMMD robot are performed and verified in a simulation platform. A new modular joint has been developed to optimize the yaw joint actuator for easy assembly and flexibility reduction. A 3-DOF gripper with cameras and torque sensor has been designed to provide inspection and dexterous handling of small fragments inside the EAST chamber. A conceptual upgrade for EAMA-CASK has been developed for the purpose of protecting the end-effector's sensors which do not have temperature-resistant qualification. The high temperature and vacuum compatible solutions and validation experiments have been presented in this paper.

  17. BLIG: A New Approach for Sensor Identification, Grouping,and Authorisation in Body Sensor Networks

    DEFF Research Database (Denmark)

    Andersen, Jacob; Bardram, Jakob Eyvind

    2007-01-01

    Using body sensor networks (BSN) in critical clinical settings like emergency units in hospitals or in accidents requires that such a network can be deployed, configured, and started in a fast and easy way, while maintaining trust in the network. In this paper we present a novel approach called...... BLIG (Blinking Led Indicated Grouping) for easy deployment of BSNs on patients in critical situations, including mechanisms for uniquely identifying and grouping sensor nodes belonging to a patient in a secure and trusted way. This approach has been designed in close cooperation with users, and easy...

  18. Hybrid architecture for building secure sensor networks

    Science.gov (United States)

    Owens, Ken R., Jr.; Watkins, Steve E.

    2012-04-01

    Sensor networks have various communication and security architectural concerns. Three approaches are defined to address these concerns for sensor networks. The first area is the utilization of new computing architectures that leverage embedded virtualization software on the sensor. Deploying a small, embedded virtualization operating system on the sensor nodes that is designed to communicate to low-cost cloud computing infrastructure in the network is the foundation to delivering low-cost, secure sensor networks. The second area focuses on securing the sensor. Sensor security components include developing an identification scheme, and leveraging authentication algorithms and protocols that address security assurance within the physical, communication network, and application layers. This function will primarily be accomplished through encrypting the communication channel and integrating sensor network firewall and intrusion detection/prevention components to the sensor network architecture. Hence, sensor networks will be able to maintain high levels of security. The third area addresses the real-time and high priority nature of the data that sensor networks collect. This function requires that a quality-of-service (QoS) definition and algorithm be developed for delivering the right data at the right time. A hybrid architecture is proposed that combines software and hardware features to handle network traffic with diverse QoS requirements.

  19. Web-Based Interface for Command and Control of Network Sensors

    Science.gov (United States)

    Wallick, Michael N.; Doubleday, Joshua R.; Shams, Khawaja S.

    2010-01-01

    This software allows for the visualization and control of a network of sensors through a Web browser interface. It is currently being deployed for a network of sensors monitoring Mt. Saint Helen s volcano; however, this innovation is generic enough that it can be deployed for any type of sensor Web. From this interface, the user is able to fully control and monitor the sensor Web. This includes, but is not limited to, sending "test" commands to individual sensors in the network, monitoring for real-world events, and reacting to those events

  20. Concept of Operations for Nuclear Warhead Embedded Sensors

    Energy Technology Data Exchange (ETDEWEB)

    Rockett, P D; Koncher, T R

    2012-05-16

    Embedded arms-control-sensors provide a powerful new paradigm for managing compliance with future nuclear weapons treaties, where deployed warhead numbers will be reduced to 1000 or less. The CONOPS (Concept of Operations) for use with these sensors is a practical tool with which one may help define design parameters, including size, power, resolution, communications, and physical structure. How frequently must data be acquired and must a human be present? Will such data be acquired for only stored weapons or will it be required of deployed weapons as well? Will tactical weapons be subject to such monitoring or will only strategic weapons apply? Which data will be most crucial? Will OSI's be a component of embedded sensor data management or will these sensors stand alone in their data extraction processes? The problem space is massive, but can be constrained by extrapolating to a reasonable future treaty regime and examining the bounded options this scenario poses. Arms control verification sensors, embedded within the warhead case or aeroshell, must provide sufficient but not excessively detailed data, confirming that the item is a nuclear warhead and that it is a particular warhead without revealing sensitive information. Geolocation will be provided by an intermediate transceiver used to acquire the data and to forward the data to a central processing location. Past Chain-of-Custody projects have included such devices and will be primarily responsible for adding such indicators in the future. For the purposes of a treaty regime a TLI will be verified as a nuclear warhead by knowledge of (a) the presence and mass of SNM, (b) the presence of HE, and (c) the reporting of a unique tag ID. All of these parameters can be obtained via neutron correlation measurements, Raman spectroscopy, and fiber optic grating fabrication, respectively. Data from these sensors will be pushed out monthly and acquired nearly daily, providing one of several verification layers in

  1. A Fault Tolerance Mechanism for On-Road Sensor Networks

    Directory of Open Access Journals (Sweden)

    Lei Feng

    2016-12-01

    Full Text Available On-Road Sensor Networks (ORSNs play an important role in capturing traffic flow data for predicting short-term traffic patterns, driving assistance and self-driving vehicles. However, this kind of network is prone to large-scale communication failure if a few sensors physically fail. In this paper, to ensure that the network works normally, an effective fault-tolerance mechanism for ORSNs which mainly consists of backup on-road sensor deployment, redundant cluster head deployment and an adaptive failure detection and recovery method is proposed. Firstly, based on the N − x principle and the sensors’ failure rate, this paper formulates the backup sensor deployment problem in the form of a two-objective optimization, which explains the trade-off between the cost and fault resumption. In consideration of improving the network resilience further, this paper introduces a redundant cluster head deployment model according to the coverage constraint. Then a common solving method combining integer-continuing and sequential quadratic programming is explored to determine the optimal location of these two deployment problems. Moreover, an Adaptive Detection and Resume (ADR protocol is deigned to recover the system communication through route and cluster adjustment if there is a backup on-road sensor mismatch. The final experiments show that our proposed mechanism can achieve an average 90% recovery rate and reduce the average number of failed sensors at most by 35.7%.

  2. Active self-testing noise measurement sensors for large-scale environmental sensor networks.

    Science.gov (United States)

    Domínguez, Federico; Cuong, Nguyen The; Reinoso, Felipe; Touhafi, Abdellah; Steenhaut, Kris

    2013-12-13

    Large-scale noise pollution sensor networks consist of hundreds of spatially distributed microphones that measure environmental noise. These networks provide historical and real-time environmental data to citizens and decision makers and are therefore a key technology to steer environmental policy. However, the high cost of certified environmental microphone sensors render large-scale environmental networks prohibitively expensive. Several environmental network projects have started using off-the-shelf low-cost microphone sensors to reduce their costs, but these sensors have higher failure rates and produce lower quality data. To offset this disadvantage, we developed a low-cost noise sensor that actively checks its condition and indirectly the integrity of the data it produces. The main design concept is to embed a 13 mm speaker in the noise sensor casing and, by regularly scheduling a frequency sweep, estimate the evolution of the microphone's frequency response over time. This paper presents our noise sensor's hardware and software design together with the results of a test deployment in a large-scale environmental network in Belgium. Our middle-range-value sensor (around €50) effectively detected all experienced malfunctions, in laboratory tests and outdoor deployments, with a few false positives. Future improvements could further lower the cost of our sensor below €10.

  3. Sensors, Volume 4, Thermal Sensors

    Science.gov (United States)

    Scholz, Jorg; Ricolfi, Teresio

    1996-12-01

    'Sensors' is the first self-contained series to deal with the whole area of sensors. It describes general aspects, technical and physical fundamentals, construction, function, applications and developments of the various types of sensors. This volume describes the construction and applicational aspects of thermal sensors while presenting a rigorous treatment of the underlying physical principles. It provides a unique overview of the various categories of sensors as well as of specific groups, e.g. temperature sensors (resistance thermometers, thermocouples, and radiation thermometers), noise and acoustic thermometers, heat-flow and mass-flow sensors. Specific facettes of applications are presented by specialists from different fields including process control, automotive technology and cryogenics. This volume is an indispensable reference work and text book for both specialists and newcomers, researchers and developers.

  4. Service and device discovery of nodes in a wireless sensor network

    NARCIS (Netherlands)

    Östmark, Å.; Lindgren, P.; van Halteren, Aart; Meppelink, L.

    2006-01-01

    Emerging wireless communication standards and more capable sensors and actuators have pushed further development of wireless sensor networks. Deploying a large number of sensor nodes requires a high-level framework enabling the devices to present themselves and the resources they hold. The device

  5. Industrial wireless sensor networks applications, protocols, and standards

    CERN Document Server

    Güngör, V Çagri

    2013-01-01

    The collaborative nature of industrial wireless sensor networks (IWSNs) brings several advantages over traditional wired industrial monitoring and control systems, including self-organization, rapid deployment, flexibility, and inherent intelligent processing. In this regard, IWSNs play a vital role in creating more reliable, efficient, and productive industrial systems, thus improving companies' competitiveness in the marketplace. Industrial Wireless Sensor Networks: Applications, Protocols, and Standards examines the current state of the art in industrial wireless sensor networks and outline

  6. A Review of Various Security Protocols in Wireless Sensor Network

    OpenAIRE

    Anupma Sangwan; Deepti Sindhu; Kulbir Singh

    2011-01-01

    Sensor networks are highly distributed networks of small, lightweight wireless sensor nodes, deployed in large numbers to monitor the environment or system by the measurement of physical parameters such as temperature, pressure, or relative humidity, sound, vibration, motion or pollutants, at different locations. A WSN [1] is composed of a large number of low-cost sensor nodes (SNs) and one or several base stations (BS) or destination nodes. SNs are typically small wireless devices with limit...

  7. MASY: Management of secret keys in federated wireless sensor networks

    OpenAIRE

    Maerien, Jef; Michiels, Sam; Huygens, Christophe; Joosen, Wouter

    2010-01-01

    Wireless Sensor Networks are becoming federated and mobile environments. These new capabilities pose a lot of new possibilities and challenges. One of these challenges is to create a secure environment to allow multiple trusted companies to share and merge their sensor network infrastructure. The most basic need for a secure environment is the deployment of key material. However, most current day research assumes pre-shared secrets between the sensor nodes of most, if not all, companies in a ...

  8. Energy autonomous sensors in the automobile; Energieautarke Sensorik im Automobil

    Energy Technology Data Exchange (ETDEWEB)

    Kuehne, Ingo [Hochschule Heilbronn (Germany). Studiengang Energieoekologie; Schreiter, Matthias [Siemens AG, Muenchen (Germany); Li, Xiaoming [Daimler AG, Sindelfingen (Germany); Hehn, Thorsten [Hahn-Schickard-Gesellschaft fuer angewandte Forschung e.V., Freiburg (Germany). HSG-IMIT, Inst. fuer Mikro- und Informationstechnik; Thewes, Marcell; Scholl, Gerd [Helmut-Schmidt-Univ., Univ. der Bundeswehr, Hamburg (Germany); Wagner, Dieter [Continental Automotive GmbH, Regensburg (Germany); Manoli, Yiannos [Univ. Freiburg (Germany). IMTEK; Frey, Alexander [Hochschule Augsburg (Germany). Fakultaet Elektrotechnik

    2013-04-01

    A brief outline of energy autonomous sensors in the automobile is given. For this purpose the variety of sensors in today's automotive vehicles is reported. The rationale for the deployment of energy autonomous sensors is given. In addition the potential of using environmental energy and the possibilities of their energy conversion are presented. As part of the funded project ASYMOF, two pioneer applications - a tire pressure monitoring and an anti-theft alarm system - are studied and discussed.

  9. Rover deployment system for lunar landing mission

    Science.gov (United States)

    Sutoh, Masataku; Hoshino, Takeshi; Wakabayashi, Sachiko

    2017-09-01

    For lunar surface exploration, a deployment system is necessary to allow a rover to leave the lander. The system should be as lightweight as possible and stored retracted when launched. In this paper, two types of retractable deployment systems for lunar landing missions, telescopic- and fold-type ramps, are discussed. In the telescopic-type system, a ramp is stored with the sections overlapping and slides out during deployment. In the fold-type system, it is stored folded and unfolds for the deployment. For the development of these ramps, a design concept study and structural analysis were conducted first. Subsequently, ramp deployment and rover release tests were performed using the developed ramp prototypes. Through these tests, the validity of their design concepts and functions have been confirmed. In the rover release test, it was observed that the developed lightweight ramp was sufficiently strong for a 50-kg rover to descend. This result suggests that this ramp system is suitable for the deployment of a 300-kg-class rover on the Moon, where the gravity is about one-sixth that on Earth. The lightweight and sturdy ramp developed in this study will contribute to both safe rover deployment and increase of lander/rover payload.

  10. Wireless sensor networks distributed consensus estimation

    CERN Document Server

    Chen, Cailian; Guan, Xinping

    2014-01-01

    This SpringerBrief evaluates the cooperative effort of sensor nodes to accomplish high-level tasks with sensing, data processing and communication. The metrics of network-wide convergence, unbiasedness, consistency and optimality are discussed through network topology, distributed estimation algorithms and consensus strategy. Systematic analysis reveals that proper deployment of sensor nodes and a small number of low-cost relays (without sensing function) can speed up the information fusion and thus improve the estimation capability of wireless sensor networks (WSNs). This brief also investiga

  11. Capacitive tool standoff sensor for dismantlement tasks

    International Nuclear Information System (INIS)

    Schmitt, D.J.; Weber, T.M.; Liu, J.C.

    1996-01-01

    A capacitive sensing technology has been applied to develop a Standoff Sensor System for control of robotically deployed tools utilized in Decontamination and Dismantlement (D and D) activities. The system combines four individual sensor elements to provide non-contact, multiple degree-of-freedom control of tools at distances up to five inches from a surface. The Standoff Sensor has been successfully integrated to a metal cutting router and a pyrometer, and utilized for real-time control of each of these tools. Experiments demonstrate that the system can locate stationary surfaces with a repeatability of 0.034 millimeters

  12. Miniature field deployable terahertz source

    Science.gov (United States)

    Mayes, Mark G.

    2006-05-01

    Developments in terahertz sources include compacted electron beam systems, optical mixing techniques, and multiplication of microwave frequencies. Although significant advances in THz science have been achieved, efforts continue to obtain source technologies that are more mobile and suitable for field deployment. Strategies in source development have approached generation from either end of the THz spectrum, from up-conversion of high-frequency microwave to down-conversion of optical frequencies. In this paper, we present the design of a THz source which employs an up-conversion method in an assembly that integrates power supply, electronics, and radiative component into a man-portable unit for situations in which a lab system is not feasible. This unit will ultimately evolve into a ruggedized package suitable for use in extreme conditions, e.g. temporary security check points or emergency response teams, in conditions where THz diagnostics are needed with minimal planning or logistical support. In order to meet design goals of reduced size and complexity, the inner workings of the unit ideally would be condensed into a monolithic active element, with ancillary systems, e.g. user interface and power, coupled to the element. To attain these goals, the fundamental component of our design is a THz source and lens array that may be fabricated with either printed circuit board or wafer substrate. To reduce the volume occupied by the source array, the design employs a metamaterial composed of a periodic lattice of resonant elements. Each resonant element is an LC oscillator, or tank circuit, with inductance, capacitance, and center frequency determined by dimensioning and material parameters. The source array and supporting electronics are designed so that the radiative elements are driven in-phase to yield THz radiation with a high degree of partial coherence. Simulation indicates that the spectral width of operation may be controlled by detuning of critical dimensions

  13. Distributed sensor coordination for advanced energy systems

    Energy Technology Data Exchange (ETDEWEB)

    Tumer, Kagan [Oregon State Univ., Corvallis, OR (United States). School of Mechanical, Industrial and Manufacturing Engineering

    2015-03-12

    Motivation: The ability to collect key system level information is critical to the safe, efficient and reliable operation of advanced power systems. Recent advances in sensor technology have enabled some level of decision making directly at the sensor level. However, coordinating large numbers of sensors, particularly heterogeneous sensors, to achieve system level objectives such as predicting plant efficiency, reducing downtime or predicting outages requires sophisticated coordination algorithms. Indeed, a critical issue in such systems is how to ensure the interaction of a large number of heterogenous system components do not interfere with one another and lead to undesirable behavior. Objectives and Contributions: The long-term objective of this work is to provide sensor deployment, coordination and networking algorithms for large numbers of sensors to ensure the safe, reliable, and robust operation of advanced energy systems. Our two specific objectives are to: 1. Derive sensor performance metrics for heterogeneous sensor networks. 2. Demonstrate effectiveness, scalability and reconfigurability of heterogeneous sensor network in advanced power systems. The key technical contribution of this work is to push the coordination step to the design of the objective functions of the sensors, allowing networks of heterogeneous sensors to be controlled. By ensuring that the control and coordination is not specific to particular sensor hardware, this approach enables the design and operation of large heterogeneous sensor networks. In addition to the coordination coordination mechanism, this approach allows the system to be reconfigured in response to changing needs (e.g., sudden external events requiring new responses) or changing sensor network characteristics (e.g., sudden changes to plant condition). Impact: The impact of this work extends to a large class of problems relevant to the National Energy Technology Laboratory including sensor placement, heterogeneous sensor

  14. A Secure Localization Approach Using Mutual Authentication and Insider Node Validation in Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Gulshan Kumar

    2017-01-01

    Full Text Available Localization is a concerning issue in the applications of wireless sensor networks. Along with the accuracy of the location estimation of the sensor nodes, the security of the estimation is another priority. Wireless sensor networks often face various attacks where the attackers try to manipulate the estimated location or try to provide false beacons. In this paper, we have proposed a methodology that will address this problem of security aspects in localization of the sensor nodes. Moreover, we have considered the network environment with random node deployment and mobility as these two conditions are less addressed in previous research works. Further, our proposed algorithm provides low overhead due to the usage of less control messages in a limited transmission range. In addition, we have also proposed an algorithm to detect the malicious anchor nodes inside the network. The simulated results show that our proposed algorithm is efficient in terms of time consumption, localization accuracy, and localization ratio in the presence of malicious nodes.

  15. Energy-Efficient Implementation of ECDH Key Exchange for Wireless Sensor Networks

    Science.gov (United States)

    Lederer, Christian; Mader, Roland; Koschuch, Manuel; Großschädl, Johann; Szekely, Alexander; Tillich, Stefan

    Wireless Sensor Networks (WSNs) are playing a vital role in an ever-growing number of applications ranging from environmental surveillance over medical monitoring to home automation. Since WSNs are often deployed in unattended or even hostile environments, they can be subject to various malicious attacks, including the manipulation and capture of nodes. The establishment of a shared secret key between two or more individual nodes is one of the most important security services needed to guarantee the proper functioning of a sensor network. Despite some recent advances in this field, the efficient implementation of cryptographic key establishment for WSNs remains a challenge due to the resource constraints of small sensor nodes such as the MICAz mote. In this paper we present a lightweight implementation of the elliptic curve Diffie-Hellman (ECDH) key exchange for ZigBee-compliant sensor nodes equipped with an ATmega128 processor running the TinyOS operating system. Our implementation uses a 192-bit prime field specified by the NIST as underlying algebraic structure and requires only 5.20 ·106 clock cycles to compute a scalar multiplication if the base point is fixed and known a priori. A scalar multiplication using a random base point takes about 12.33 ·106 cycles. Our results show that a full ECDH key exchange between two MICAz motes consumes an energy of 57.33 mJ (including radio communication), which is significantly better than most previously reported ECDH implementations on comparable platforms.

  16. Deploying temporary networks for upscaling of sparse network stations

    Science.gov (United States)

    Coopersmith, Evan J.; Cosh, Michael H.; Bell, Jesse E.; Kelly, Victoria; Hall, Mark; Palecki, Michael A.; Temimi, Marouane

    2016-10-01

    Soil observations networks at the national scale play an integral role in hydrologic modeling, drought assessment, agricultural decision support, and our ability to understand climate change. Understanding soil moisture variability is necessary to apply these measurements to model calibration, business and consumer applications, or even human health issues. The installation of soil moisture sensors as sparse, national networks is necessitated by limited financial resources. However, this results in the incomplete sampling of the local heterogeneity of soil type, vegetation cover, topography, and the fine spatial distribution of precipitation events. To this end, temporary networks can be installed in the areas surrounding a permanent installation within a sparse network. The temporary networks deployed in this study provide a more representative average at the 3 km and 9 km scales, localized about the permanent gauge. The value of such temporary networks is demonstrated at test sites in Millbrook, New York and Crossville, Tennessee. The capacity of a single U.S. Climate Reference Network (USCRN) sensor set to approximate the average of a temporary network at the 3 km and 9 km scales using a simple linear scaling function is tested. The capacity of a temporary network to provide reliable estimates with diminishing numbers of sensors, the temporal stability of those networks, and ultimately, the relationship of the variability of those networks to soil moisture conditions at the permanent sensor are investigated. In this manner, this work demonstrates the single-season installation of a temporary network as a mechanism to characterize the soil moisture variability at a permanent gauge within a sparse network.

  17. Downhole Applications of Magnetic Sensors.

    Science.gov (United States)

    Gooneratne, Chinthaka P; Li, Bodong; Moellendick, Timothy E

    2017-10-19

    In this paper we present a review of the application of two types of magnetic sensors-fluxgate magnetometers and nuclear magnetic resonance (NMR) sensors-in the oil/gas industry. These magnetic sensors play a critical role in drilling wells safely, accurately and efficiently into a target reservoir zone by providing directional data of the well and acquiring information about the surrounding geological formations. Research into magnetic sensors for oil/gas drilling has not been explored by researchers to the same extent as other applications, such as biomedical, magnetic storage and automotive/aerospace applications. Therefore, this paper aims to serve as an opportunity for researchers to truly understand how magnetic sensors can be used in a downhole environment and to provide fertile ground for research and development in this area. A look ahead, discussing other magnetic sensor technologies that can potentially be used in the oil/gas industry is presented, and what is still needed in order deploy them in the field is also addressed.

  18. Sensor Placement Optimization using Chama

    Energy Technology Data Exchange (ETDEWEB)

    Klise, Katherine A. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Geotechnology and Engineering Dept.; Nicholson, Bethany L. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Discrete Math and Optimization Dept.; Laird, Carl Damon [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States). Discrete Math and Optimization Dept.

    2017-10-01

    Continuous or regularly scheduled monitoring has the potential to quickly identify changes in the environment. However, even with low - cost sensors, only a limited number of sensors can be deployed. The physical placement of these sensors, along with the sensor technology and operating conditions, can have a large impact on the performance of a monitoring strategy. Chama is an open source Python package which includes mixed - integer, stochastic programming formulations to determine sensor locations and technology that maximize monitoring effectiveness. The methods in Chama are general and can be applied to a wide range of applications. Chama is currently being used to design sensor networks to monitor airborne pollutants and to monitor water quality in water distribution systems. The following documentation includes installation instructions and examples, description of software features, and software license. The software is intended to be used by regulatory agencies, industry, and the research community. It is assumed that the reader is familiar with the Python Programming Language. References are included for addit ional background on software components. Online documentation, hosted at http://chama.readthedocs.io/, will be updated as new features are added. The online version includes API documentation .

  19. On the Design of Smart Parking Networks in the Smart Cities: An Optimal Sensor Placement Model

    Science.gov (United States)

    Bagula, Antoine; Castelli, Lorenzo; Zennaro, Marco

    2015-01-01

    Smart parking is a typical IoT application that can benefit from advances in sensor, actuator and RFID technologies to provide many services to its users and parking owners of a smart city. This paper considers a smart parking infrastructure where sensors are laid down on the parking spots to detect car presence and RFID readers are embedded into parking gates to identify cars and help in the billing of the smart parking. Both types of devices are endowed with wired and wireless communication capabilities for reporting to a gateway where the situation recognition is performed. The sensor devices are tasked to play one of the three roles: (1) slave sensor nodes located on the parking spot to detect car presence/absence; (2) master nodes located at one of the edges of a parking lot to detect presence and collect the sensor readings from the slave nodes; and (3) repeater sensor nodes, also called “anchor” nodes, located strategically at specific locations in the parking lot to increase the coverage and connectivity of the wireless sensor network. While slave and master nodes are placed based on geographic constraints, the optimal placement of the relay/anchor sensor nodes in smart parking is an important parameter upon which the cost and efficiency of the parking system depends. We formulate the optimal placement of sensors in smart parking as an integer linear programming multi-objective problem optimizing the sensor network engineering efficiency in terms of coverage and lifetime maximization, as well as its economic gain in terms of the number of sensors deployed for a specific coverage and lifetime. We propose an exact solution to the node placement problem using single-step and two-step solutions implemented in the Mosel language based on the Xpress-MPsuite of libraries. Experimental results reveal the relative efficiency of the single-step compared to the two-step model on different performance parameters. These results are consolidated by simulation results

  20. On the Design of Smart Parking Networks in the Smart Cities: An Optimal Sensor Placement Model

    Directory of Open Access Journals (Sweden)

    Antoine Bagula

    2015-06-01

    Full Text Available Smart parking is a typical IoT application that can benefit from advances in sensor, actuator and RFID technologies to provide many services to its users and parking owners of a smart city. This paper considers a smart parking infrastructure where sensors are laid down on the parking spots to detect car presence and RFID readers are embedded into parking gates to identify cars and help in the billing of the smart parking. Both types of devices are endowed with wired and wireless communication capabilities for reporting to a gateway where the situation recognition is performed. The sensor devices are tasked to play one of the three roles: (1 slave sensor nodes located on the parking spot to detect car presence/absence; (2 master nodes located at one of the edges of a parking lot to detect presence and collect the sensor readings from the slave nodes; and (3 repeater sensor nodes, also called “anchor” nodes, located strategically at specific locations in the parking lot to increase the coverage and connectivity of the wireless sensor network. While slave and master nodes are placed based on geographic constraints, the optimal placement of the relay/anchor sensor nodes in smart parking is an important parameter upon which the cost and efficiency of the parking system depends. We formulate the optimal placement of sensors in smart parking as an integer linear programming multi-objective problem optimizing the sensor network engineering efficiency in terms of coverage and lifetime maximization, as well as its economic gain in terms of the number of sensors deployed for a specific coverage and lifetime. We propose an exact solution to the node placement problem using single-step and two-step solutions implemented in the Mosel language based on the Xpress-MPsuite of libraries. Experimental results reveal the relative efficiency of the single-step compared to the two-step model on different performance parameters. These results are consolidated by

  1. On the Design of Smart Parking Networks in the Smart Cities: An Optimal Sensor Placement Model.

    Science.gov (United States)

    Bagula, Antoine; Castelli, Lorenzo; Zennaro, Marco

    2015-06-30

    Smart parking is a typical IoT application that can benefit from advances in sensor, actuator and RFID technologies to provide many services to its users and parking owners of a smart city. This paper considers a smart parking infrastructure where sensors are laid down on the parking spots to detect car presence and RFID readers are embedded into parking gates to identify cars and help in the billing of the smart parking. Both types of devices are endowed with wired and wireless communication capabilities for reporting to a gateway where the situation recognition is performed. The sensor devices are tasked to play one of the three roles: (1) slave sensor nodes located on the parking spot to detect car presence/absence; (2) master nodes located at one of the edges of a parking lot to detect presence and collect the sensor readings from the slave nodes; and (3) repeater sensor nodes, also called "anchor" nodes, located strategically at specific locations in the parking lot to increase the coverage and connectivity of the wireless sensor network. While slave and master nodes are placed based on geographic constraints, the optimal placement of the relay/anchor sensor nodes in smart parking is an important parameter upon which the cost and efficiency of the parking system depends. We formulate the optimal placement of sensors in smart parking as an integer linear programming multi-objective problem optimizing the sensor network engineering efficiency in terms of coverage and lifetime maximization, as well as its economic gain in terms of the number of sensors deployed for a specific coverage and lifetime. We propose an exact solution to the node placement problem using single-step and two-step solutions implemented in the Mosel language based on the Xpress-MPsuite of libraries. Experimental results reveal the relative efficiency of the single-step compared to the two-step model on different performance parameters. These results are consolidated by simulation results

  2. Gas Sensor

    KAUST Repository

    Luebke, Ryan

    2015-01-22

    A gas sensor using a metal organic framework material can be fully integrated with related circuitry on a single substrate. In an on-chip application, the gas sensor can result in an area-efficient fully integrated gas sensor solution. In one aspect, a gas sensor can include a first gas sensing region including a first pair of electrodes, and a first gas sensitive material proximate to the first pair of electrodes, wherein the first gas sensitive material includes a first metal organic framework material.

  3. Gas Sensor

    KAUST Repository

    Luebke, Ryan; Eddaoudi, Mohamed; Omran, Hesham; Belmabkhout, Youssef; Shekhah, Osama; Salama, Khaled N.

    2015-01-01

    A gas sensor using a metal organic framework material can be fully integrated with related circuitry on a single substrate. In an on-chip application, the gas sensor can result in an area-efficient fully integrated gas sensor solution. In one aspect, a gas sensor can include a first gas sensing region including a first pair of electrodes, and a first gas sensitive material proximate to the first pair of electrodes, wherein the first gas sensitive material includes a first metal organic framework material.

  4. Sensor web

    Science.gov (United States)

    Delin, Kevin A. (Inventor); Jackson, Shannon P. (Inventor)

    2011-01-01

    A Sensor Web formed of a number of different sensor pods. Each of the sensor pods include a clock which is synchronized with a master clock so that all of the sensor pods in the Web have a synchronized clock. The synchronization is carried out by first using a coarse synchronization which takes less power, and subsequently carrying out a fine synchronization to make a fine sync of all the pods on the Web. After the synchronization, the pods ping their neighbors to determine which pods are listening and responded, and then only listen during time slots corresponding to those pods which respond.

  5. Walking Training with Foot Drop Stimulator Controlled by a Tilt Sensor to Improve Walking Outcomes: A Randomized Controlled Pilot Study in Patients with Stroke in Subacute Phase

    Directory of Open Access Journals (Sweden)

    G. Morone

    2012-01-01

    Full Text Available Foot drop is a quite common problem in nervous system disorders. Neuromuscular electrical stimulation (NMES has showed to be an alternative approach to correct foot drop improving walking ability in patients with stroke. In this study, twenty patients with stroke in subacute phase were enrolled and randomly divided in two groups: one group performing the NMES (i.e. Walkaide Group, WG and the Control Group (CG performing conventional neuromotor rehabilitation. Both groups underwent the same amount of treatment time. Significant improvements of walking speed were recorded for WG (% than for CG (%, as well as in terms of locomotion (Functional Ambulation Classification score: . In terms of mobility and force, ameliorations were recorded, even if not significant (Rivermead Mobility Index: ; Manual Muscle Test: . Similar changes between groups were observed for independence in activities of daily living, neurological assessments, and spasticity reduction. These results highlight the potential efficacy for patients affected by a droop foot of a walking training performed with a neurostimulator in subacute phase.

  6. CLOUD COMPUTING AND INTERNET OF THINGS FOR SMART CITY DEPLOYMENTS

    Directory of Open Access Journals (Sweden)

    GEORGE SUCIU

    2013-05-01

    Full Text Available Cloud Computing represents the new method of delivering hardware and software resources to the users, Internet of Things (IoT is currently one of the most popular ICT paradigms. Both concepts can have a major impact on how we build smart or/and smarter cities. Cloud computing represents the delivery of hardware and software resources on-demand over the Internet as a Service. At the same time, the IoT concept envisions a new generation of devices (sensors, both virtual and physical that are connected to the Internet and provide different services for value-added applications. In this paper we present our view on how to deploy Cloud computing and IoT for smart or/and smarter cities. We demonstrate that data gathered from heterogeneous and distributed IoT devices can be automatically managed, handled and reused with decentralized cloud services.

  7. Wireless sensor network for sodium leak detection

    International Nuclear Information System (INIS)

    Satya Murty, S.A.V.; Raj, Baldev; Sivalingam, Krishna M.; Ebenezer, Jemimah; Chandran, T.; Shanmugavel, M.; Rajan, K.K.

    2012-01-01

    Highlights: ► Early detection of sodium leak is mandatory in any reactor handling liquid sodium. ► Wireless sensor networking technology has been introduced for detecting sodium leak. ► We designed and developed a wireless sensor node in-house. ► We deployed a pilot wireless sensor network for handling nine sodium leak signals. - Abstract: To study the mechanical properties of Prototype Fast Breeder Reactor component materials under the influence of sodium, the IN Sodium Test (INSOT) facility has been erected and commissioned at Indira Gandhi Centre for Atomic Research. Sodium reacts violently with air/moisture leading to fire. Hence early detection of sodium leak if any is mandatory for such plants and almost 140 sodium leak detectors are placed throughout the loop. All these detectors are wired to the control room for data collection and monitoring. To reduce the cost, space and maintenance that are involved in cabling, the wireless sensor networking technology has been introduced in the sodium leak detection system of INSOT. This paper describes about the deployment details of the pilot wireless sensor network and the measures taken for the successful deployment.

  8. Sensor fusion for intelligent alarm analysis

    International Nuclear Information System (INIS)

    Nelson, C.L.; Fitzgerald, D.S.

    1996-01-01

    The purpose of an intelligent alarm analysis system is to provide complete and manageable information to a central alarm station operator by applying alarm processing and fusion techniques to sensor information. This paper discusses the sensor fusion approach taken to perform intelligent alarm analysis for the Advanced Exterior Sensor (AES). The AES is an intrusion detection and assessment system designed for wide-area coverage, quick deployment, low false/nuisance alarm operation, and immediate visual assessment. It combines three sensor technologies (visible, infrared, and millimeter wave radar) collocated on a compact and portable remote sensor module. The remote sensor module rotates at a rate of 1 revolution per second to detect and track motion and provide assessment in a continuous 360 degree field-of-regard. Sensor fusion techniques are used to correlate and integrate the track data from these three sensors into a single track for operator observation. Additional inputs to the fusion process include environmental data, knowledge of sensor performance under certain weather conditions, sensor priority, and recent operator feedback. A confidence value is assigned to the track as a result of the fusion process. This helps to reduce nuisance alarms and to increase operator confidence in the system while reducing the workload of the operator

  9. Project implementation plan: ASTD remote deployment

    International Nuclear Information System (INIS)

    CRASS, D.W.

    1999-01-01

    This document is the project implementation plan for the ASTD Remote Deployment Project. The Plan identifies the roles and responsibilities for the project and defines the integration between the ASTD Project and the B-Cell Cleanout Project

  10. Office of Civilian Response Deployment Tracking System

    Data.gov (United States)

    US Agency for International Development — The purpose of OCR DTS is to establish, manage and track relevant Civilian Response Corps teams for deployment by sector experience, training, education etc.

  11. RadNet Air Quality (Deployable) Data

    Data.gov (United States)

    U.S. Environmental Protection Agency — RadNet Deployable Monitoring is designed to collect radiological and meteorological information and data asset needed to establish the impact of radiation levels on...

  12. Self-Deploying, Composite Habitats, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Cornerstone Research Group, Inc. (CRG), proposes to develop self-deploying, composite structures for lunar habitats, based on CRG's VeritexTM materials. These...

  13. Small cell networks deployment, management, and optimization

    CERN Document Server

    Claussen, Holger; Ho, Lester; Razavi, Rouzbeh; Kucera, Stepan

    2018-01-01

    Small Cell Networks: Deployment, Management, and Optimization addresses key problems of the cellular network evolution towards HetNets. It focuses on the latest developments in heterogeneous and small cell networks, as well as their deployment, operation, and maintenance. It also covers the full spectrum of the topic, from academic, research, and business to the practice of HetNets in a coherent manner. Additionally, it provides complete and practical guidelines to vendors and operators interested in deploying small cells. The first comprehensive book written by well-known researchers and engineers from Nokia Bell Labs, Small Cell Networks begins with an introduction to the subject--offering chapters on capacity scaling and key requirements of future networks. It then moves on to sections on coverage and capacity optimization, and interference management. From there, the book covers mobility management, energy efficiency, and small cell deployment, ending with a section devoted to future trends and applicat...

  14. Community integration after deployment to Afghanistan

    DEFF Research Database (Denmark)

    Karstoft, Karen-Inge; Armour, Cherie; Andersen, Søren B.

    2015-01-01

    OBJECTIVE: In the years following military deployment, soldiers may experience problems integrating into the community. However, little is known about the nature and prevalence of these problems and if they relate to posttraumatic symptomatology. METHODS: In a prospective, longitudinal study...

  15. Deployment strategies of managed lanes on arterials.

    Science.gov (United States)

    2015-02-01

    This report investigates issues related to planning, financing, deployment, and operation of managed : lanes on arterials. In this report, a strategy for managed lanes refers to a combination of the managed : lane type, the design and implementation,...

  16. Deploying Missile Defense: Major Operational Challenges

    National Research Council Canada - National Science Library

    Bunn, M

    2004-01-01

    By October 2004, the United States will have begun initial deployment of a missile defense capability albeit a modest, limited, and not completely proven one to defend the homeland against a limited...

  17. Deployable structures for a human lunar base

    Science.gov (United States)

    Gruber, Petra; Häuplik, Sandra; Imhof, Barbara; Özdemir, Kürsad; Waclavicek, Rene; Perino, Maria Antoinetta

    2007-06-01

    The study Lunar exploration architecture—deployable structures for a lunar base was performed within the Alcatel Alenia Space “Lunar Exploration Architecture” study for the European Space Agency. The purpose of the study was to investigate bionic concepts applicable to deployable structures and to interpret the findings for possible implementation concepts. The study aimed at finding innovative solutions for deployment possibilities. Translating folding/unfolding principles from nature, candidate geometries were developed and researched using models, drawings and visualisations. The use of materials, joints between structural elements and construction details were investigated for these conceptual approaches. Reference scenarios were used to identify the technical and environmental conditions, which served as design drivers. Mechanical issues and the investigation of deployment processes narrowed the selection down to six chosen concepts. Their applicability was evaluated at a conceptual stage in relation to the timescale of the mission.

  18. Military Families: Child Care Support During Deployments

    Science.gov (United States)

    ... temporary caregiver far in advance will make your children feel more secure. Try to have the caregiver connect prior to deployment through visits, phone calls, or social media. If you will be relocating to a family ...

  19. Concept of Deployable Network Operations Center (DNOC)

    National Research Council Canada - National Science Library

    Bordetsky, Alex; Thiry, Jeff; Johnson, Shawn

    2005-01-01

    .... The increasing use of expeditionary and special operations forces in ad hoc, dynamic, and tactical environments poses a need for an adaptable, flexible, and responsive deployable network operations center (DNOC...

  20. In-Flight Suppressant Deployment Temperatures

    National Research Council Canada - National Science Library

    Bein, Donald

    2006-01-01

    .... An assessment is made of the model output versus some aircraft measurement data, fire suppressant boiling point criterion, as well as the history of altitude/temperature at which fire suppressants have been deployed...

  1. Demonstration and Deployment Strategy Workshop: Summary

    Energy Technology Data Exchange (ETDEWEB)

    none,

    2014-05-01

    This report is based on the proceedings of the U.S. Department of Energy Bioenergy Technologies Office Demonstration and Deployment Strategy Workshop, held on March 12–13, 2014, at Argonne National Laboratory.

  2. NEON's Mobile Deployment Platform: A Resource for Community Research

    Science.gov (United States)

    Sanclements, M.

    2017-12-01

    Here we provide an update on construction of the five NEON Mobile Deployment Platforms (MDPs) as well as a description of the infrastructure and sensors available to researchers in the near future. Additionally, we include information (i.e. timelines and procedures) on requesting MDPs for PI led projects. The MDPs will provide the means to observe stochastic or spatially important events, gradients, or quantities that cannot be reliably observed using fixed location sampling (e.g. fires and floods). Due to the transient temporal and spatial nature of such events, the MDPs are designed to accommodate rapid deployment for time periods up to 1 year. Broadly, the MDPs are comprised of infrastructure and instrumentation capable of functioning individually or in conjunction with one another to support observations of ecological change, as well as education, training and outreach. More specifically, the MDPs include the capability to make tower based measures of ecosystem exchange, radiation, and precipitation in conjunction with baseline soils data such as CO2 flux, and soil temperature and moisture. An aquatics module is also available with the MDP to facilitate research integrating terrestrial and aquatic processes. Ultimately, the NEON MDPs provide a tool for linking PI led research to the continental scale data sets collected by NEON.

  3. Sensor array signal processing

    CERN Document Server

    Naidu, Prabhakar S

    2009-01-01

    Chapter One: An Overview of Wavefields 1.1 Types of Wavefields and the Governing Equations 1.2 Wavefield in open space 1.3 Wavefield in bounded space 1.4 Stochastic wavefield 1.5 Multipath propagation 1.6 Propagation through random medium 1.7 ExercisesChapter Two: Sensor Array Systems 2.1 Uniform linear array (ULA) 2.2 Planar array 2.3 Distributed sensor array 2.4 Broadband sensor array 2.5 Source and sensor arrays 2.6 Multi-component sensor array2.7 ExercisesChapter Three: Frequency Wavenumber Processing 3.1 Digital filters in the w-k domain 3.2 Mapping of 1D into 2D filters 3.3 Multichannel Wiener filters 3.4 Wiener filters for ULA and UCA 3.5 Predictive noise cancellation 3.6 Exercises Chapter Four: Source Localization: Frequency Wavenumber Spectrum4.1 Frequency wavenumber spectrum 4.2 Beamformation 4.3 Capon's w-k spectrum 4.4 Maximum entropy w-k spectrum 4.5 Doppler-Azimuth Processing4.6 ExercisesChapter Five: Source Localization: Subspace Methods 5.1 Subspace methods (Narrowband) 5.2 Subspace methods (B...

  4. A Novel Methodology for Charging Station Deployment

    Science.gov (United States)

    Sun, Zhonghao; Zhao, Yunwei; He, Yueying; Li, Mingzhe

    2018-02-01

    Lack of charging stations has been a main obstacle to the promotion of electric vehicles. This paper studies deploying charging stations in traffic networks considering grid constraints to balance the charging demand and grid stability. First, we propose a statistical model for charging demand. Then we combine the charging demand model with power grid constraints and give the formulation of the charging station deployment problem. Finally, we propose a theoretical solution for the problem by transforming it to a Markov Decision Process.

  5. State perspectives on clean coal technology deployment

    Energy Technology Data Exchange (ETDEWEB)

    Moreland, T. [State of Illinois Washington Office, Washington, DC (United States)

    1997-12-31

    State governments have been funding partners in the Clean Coal Technology program since its beginnings. Today, regulatory and market uncertainties and tight budgets have reduced state investment in energy R and D, but states have developed program initiatives in support of deployment. State officials think that the federal government must continue to support these technologies in the deployment phase. Discussions of national energy policy must include attention to the Clean Coal Technology program and its accomplishments.

  6. DRAGON - 8U Nanosatellite Orbital Deployer

    Science.gov (United States)

    Dobrowolski, Marcin; Grygorczuk, Jerzy; Kedziora, Bartosz; Tokarz, Marta; Borys, Maciej

    2014-01-01

    The Space Research Centre of the Polish Academy of Sciences (SRC PAS) together with Astronika company have developed an Orbital Deployer called DRAGON for ejection of the Polish scientific nanosatellite BRITE-PL Heweliusz (Fig. 1). The device has three unique mechanisms including an adopted and scaled lock and release mechanism from the ESA Rosetta mission MUPUS instrument. This paper discusses major design restrictions of the deployer, unique design features, and lessons learned from development through testing.

  7. Deploying Renewables - Best and Future Policy Practice

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2011-11-23

    The global energy system faces urgent challenges. Concerns about energy security are growing, as highlighted by the recent political turmoil in Northern Africa and the nuclear incident in Fukushima. At the same time, the need to respond to climate change is more critical than ever. Against this background, many governments have increased efforts to promote deployment of renewable energy -- low-carbon sources that can strengthen energy security. This has stimulated unprecedented rise in deployment, and renewables are now the fastest growing sector of the energy mix. This 'coming of age' of renewable energy also brings challenges. Growth is focused on a few of the available technologies, and rapid deployment is confined to a relatively small number of countries. In more advanced markets, managing support costs and system integration of large shares of renewable energy in a time of economic weakness and budget austerity has sparked vigorous political debate. The IEA's new report, Deploying Renewables 2011: Best and Future Policy Practice: - Provides a comprehensive review and analysis of renewable energy policy and market trends; - Analyses in detail the dynamics of deployment and provides best-practice policy principles for different stages of market maturity; - Assesses the impact and cost-effectiveness of support policies using new methodological tools and indicators; - Investigates the strategic reasons underpinning the pursuit of RE deployment by different countries and the prospects for globalisation of RE. This new book builds on and extends a 2008 IEA publication, drawing on recent policy and deployment experience world-wide. It provides guidance for policy makers and other stakeholders to avoid past mistakes, overcome new challenges and reap the benefits of deploying renewables -- today and tomorrow.

  8. Temperature and salinity data from moored seacat sensors of the Multi-disciplinary Ocean Sensors for Environmental Analyses and Networks (MOSEAN) project 2004-2007 (NODC Accession 0115703)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Temperature and salinity data were collected by seacat sensors from seven deployments within 2004-2007 on the HALE-ALOHA mooring, a location about 100 km north of...

  9. Network performance of a wireless sensor network for temperature monitoring in vineyards

    DEFF Research Database (Denmark)

    Liscano, Ramiro; Jacoub, John Khalil; Dersingh, Anand

    2011-01-01

    Wireless sensor networks (WSNs) are an emerging technology which can be used for outdoor environmental monitoring. This paper presents challenges that arose from the development and deployment of a WSN for environmental monitoring as well as network performance analysis of this network. Different...... components in our sensor network architecture are presented like the physical nodes, the sensor node code, and two messaging protocols; one for collecting sensor and network values and the other for sensor node commands. An information model for sensor nodes to support plug-and-play capabilities in sensor...... networks is also presented....

  10. Secure Wireless Sensor Networks: Problems and Solutions

    Directory of Open Access Journals (Sweden)

    Fei Hu

    2003-08-01

    Full Text Available As sensor networks edge closer towards wide-spread deployment, security issues become a central concern. So far, the main research focus has been on making sensor networks feasible and useful, and less emphasis was placed on security. This paper analyzes security challenges in wireless sensor networks and summarizes key issues that should be solved for achieving the ad hoc security. It gives an overview of the current state of solutions on such key issues as secure routing, prevention of denial-of-service and key management service. We also present some secure methods to achieve security in wireless sensor networks. Finally we present our integrated approach to securing sensor networks.

  11. Fiber-Optic Sensing System: Overview, Development and Deployment in Flight at NASA

    Science.gov (United States)

    Chan, Hon Man; Parker, Allen R.; Piazza, Anthony; Richards, W. Lance

    2015-01-01

    An overview of the research and technological development of the fiber-optic sensing system (FOSS) at the National Aeronautics and Space Administration Armstrong Flight Research Center (NASA AFRC) is presented. Theory behind fiber Bragg grating (FBG) sensors, as well as interrogation technique based on optical frequency domain reflectometry (OFDR) is discussed. Assessment and validation of FOSS as an accurate measurement tool for structural health monitoring is realized in the laboratory environment as well as large-scale flight deployment.

  12. Space Qualification Testing of a Shape Memory Alloy Deployable CubeSat Antenna

    Science.gov (United States)

    2016-09-15

    from a specific input vibration . This excitation vibration can be applied acoustically through a speaker or physically by an impact hammer. NASA...Shape Memory Alloy (SMA) L-band deployable QHA. In this research, a testing approach is developed to conduct random vibration , thermal vacuum...92 4.4 Vibration Test Results

  13. Robust optical sensors for safety critical automotive applications

    Science.gov (United States)

    De Locht, Cliff; De Knibber, Sven; Maddalena, Sam

    2008-02-01

    Optical sensors for the automotive industry need to be robust, high performing and low cost. This paper focuses on the impact of automotive requirements on optical sensor design and packaging. Main strategies to lower optical sensor entry barriers in the automotive market include: Perform sensor calibration and tuning by the sensor manufacturer, sensor test modes on chip to guarantee functional integrity at operation, and package technology is key. As a conclusion, optical sensor applications are growing in automotive. Optical sensor robustness matured to the level of safety critical applications like Electrical Power Assisted Steering (EPAS) and Drive-by-Wire by optical linear arrays based systems and Automated Cruise Control (ACC), Lane Change Assist and Driver Classification/Smart Airbag Deployment by camera imagers based systems.

  14. Chemical sensors

    International Nuclear Information System (INIS)

    Hubbard, C.W.; Gordon, R.L.

    1987-05-01

    The revolution in analytical chemistry promised by recent developments in the field of chemical sensors has potential for significant positive impact on both research and production activities conducted by and for the Department of Energy. Analyses which were, in the past, performed only with a roomful of expensive equipment can now be performed with miniature solid-state electronic devices or small optical probes. Progress in the development of chemical sensors has been rapid, and the field is currently growing at a great rate. In accordance, Pacific Northwest Laboratory initiated a survey of recent literature so that contributors to active programs in research on analytical methods could be made aware of principles and applications of this new technology. This report presents the results of that survey. The sensors discussed here are divided into three types: micro solid-state devices, optical sensors, and piezoelectric crystal devices. The report is divided into three corresponding sections. The first section, ''Micro Solid-State Devices,'' discusses the design, operation, and application of electronic sensors that are produced in much the same way as standard solid-state electronic devices. The second section, ''Optrodes,'' covers the design and operation of chemical sensors that use fiber optics to detect chemically induced changes in optical properties. The final section, ''Piezoelectric Crystal Detectors,'' discusses two types of chemical sensors that depend on the changes in the properties of an oscillating piezoelectric crystal to detect the presence of certain materials. Advantages and disadvantages of each type of sensor are summarized in each section

  15. FUZZY LOGIC BASED ENERGY EFFICIENT PROTOCOL IN WIRELESS SENSOR NETWORKS

    Directory of Open Access Journals (Sweden)

    Zhan Wei Siew

    2012-12-01

    Full Text Available Wireless sensor networks (WSNs have been vastly developed due to the advances in microelectromechanical systems (MEMS using WSN to study and monitor the environments towards climates changes. In environmental monitoring, sensors are randomly deployed over the interest area to periodically sense the physical environments for a few months or even a year. Therefore, to prolong the network lifetime with limited battery capacity becomes a challenging issue. Low energy adaptive cluster hierarchical (LEACH is the common clustering protocol that aim to reduce the energy consumption by rotating the heavy workload cluster heads (CHs. The CHs election in LEACH is based on probability model which will lead to inefficient in energy consumption due to least desired CHs location in the network. In WSNs, the CHs location can directly influence the network energy consumption and further affect the network lifetime. In this paper, factors which will affect the network lifetime will be presented and the demonstration of fuzzy logic based CH selection conducted in base station (BS will also be carried out. To select suitable CHs that will prolong the network first node dies (FND round and consistent throughput to the BS, energy level and distance to the BS are selected as fuzzy inputs.

  16. Technical Survey on Applications of Wireless Sensor Networks in Nuclear Power Plants

    International Nuclear Information System (INIS)

    Jiang, Jin; Bari, Ataul; Chen, Dongyi; Hashemian, Hash M.

    2014-01-01

    Even though there is no general consensus on using wireless technologies in nuclear power plants, potential applications of wireless sensor networks within nuclear power plants (NPPs) has been investigated. The topics of interests include potential interaction of wireless sensor networks with the sensitive protection equipment, radiation damage of the electronics on board sensor nodes, optimal placement of relay nodes that collect and forward data in the network, and possible applications, such as radiation dose and level monitoring, and equipment condition monitoring. Several wireless sensor networks have been deployed on site of NPPs on a trial basis to perform these tasks. Different aspects of deployment of such wireless sensor networks in NPPs have also been examined. Industrial standards or guidelines for deployment of WSNs in NPPs are also been considered. This paper examines the state of the art of wireless sensor networks in NPPs

  17. Technical Survey on Applications of Wireless Sensor Networks in Nuclear Power Plants

    Energy Technology Data Exchange (ETDEWEB)

    Jiang, Jin; Bari, Ataul [University of Western Ontario, Ontario (Canada); Chen, Dongyi [University of Electronic Science and Technology of China, Chengdu (China); Hashemian, Hash M. [AMS Technology Center, Knoxville (United States)

    2014-08-15

    Even though there is no general consensus on using wireless technologies in nuclear power plants, potential applications of wireless sensor networks within nuclear power plants (NPPs) has been investigated. The topics of interests include potential interaction of wireless sensor networks with the sensitive protection equipment, radiation damage of the electronics on board sensor nodes, optimal placement of relay nodes that collect and forward data in the network, and possible applications, such as radiation dose and level monitoring, and equipment condition monitoring. Several wireless sensor networks have been deployed on site of NPPs on a trial basis to perform these tasks. Different aspects of deployment of such wireless sensor networks in NPPs have also been examined. Industrial standards or guidelines for deployment of WSNs in NPPs are also been considered. This paper examines the state of the art of wireless sensor networks in NPPs.

  18. Deployment Support Leading to Implementation

    Energy Technology Data Exchange (ETDEWEB)

    Cook, E E

    1997-10-01

    cause lateral distribution of the water. The large tank that accommodates the sand bed and the necessary plumbing to simulate various well configurations was received. The monitoring equipment and the sensors are currently being installed. The experimental procedures for Phase II experiments are under further investigation and will be initiated upon installation of CATC and assembly of the monitoring system. Due to insufficient operating funds, the large scale experiments will not be done this year. Task No. 1.3: Technical Support - Development of Standard Test Protocols and Barrier Design Models for In Situ Formed Barriers (B. Overbey & D. Locke, BDM Federal): The Operating Permit Renewal Request for bench scale operations in the FETC B-17 building was submitted to the FETC Lab Safety Committee for approval on 8/14/97. A review of the revised NEPA documents prepared last year indicates that these documents are still applicable for the current work. The initial design and specifications for the CATC vessel were prepared. Construction of the CATC was initiated in early July, the vessel was received August 15, 1997, and on-site work was completed this quarter.

  19. Simulating CubeSat Structure Deployment Dynamics, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — There is high value in simulating the nonlinear dynamics of stowing, deploying, and performance of deployable space structures, especially given the profound...

  20. Bio-Inspired Cyber Security for Smart Grid Deployments

    Energy Technology Data Exchange (ETDEWEB)

    McKinnon, Archibald D.; Thompson, Seth R.; Doroshchuk, Ruslan A.; Fink, Glenn A.; Fulp, Errin W.

    2013-05-01

    mart grid technologies are transforming the electric power grid into a grid with bi-directional flows of both power and information. Operating millions of new smart meters and smart appliances will significantly impact electric distribution systems resulting in greater efficiency. However, the scale of the grid and the new types of information transmitted will potentially introduce several security risks that cannot be addressed by traditional, centralized security techniques. We propose a new bio-inspired cyber security approach. Social insects, such as ants and bees, have developed complex-adaptive systems that emerge from the collective application of simple, light-weight behaviors. The Digital Ants framework is a bio-inspired framework that uses mobile light-weight agents. Sensors within the framework use digital pheromones to communicate with each other and to alert each other of possible cyber security issues. All communication and coordination is both localized and decentralized thereby allowing the framework to scale across the large numbers of devices that will exist in the smart grid. Furthermore, the sensors are light-weight and therefore suitable for implementation on devices with limited computational resources. This paper will provide a brief overview of the Digital Ants framework and then present results from test bed-based demonstrations that show that Digital Ants can identify a cyber attack scenario against smart meter deployments.

  1. Automotive sensors

    Science.gov (United States)

    Marek, Jiri; Illing, Matthias

    2003-01-01

    Sensors are an essential component of most electronic systems in the car. They deliver input parameters for comfort features, engine and emission control as well as for the active and passive safety systems. New technologies such as silicon micromachining play an important role for the introduction of these sensors in all vehicle classes. The importance and use of these sensor technologies in today"s automotive applications will be shown in this article. Finally an outlook on important current developments and new functions in the car will be given.

  2. Piezoceramic Sensors

    CERN Document Server

    Sharapov, Valeriy

    2011-01-01

    This book presents the latest and complete information about various types of piezosensors. A sensor is a converter of the measured physical size to an electric signal. Piezoelectric transducers and sensors are based on piezoelectric effects. They have proven to be versatile tools for the measurement of various processes. They are used for quality assurance, process control and for research and development in many different industries. In each area of application specific requirements to the parameters of transducers and sensors are developed. This book presents the fundamentals, technical des

  3. Environmental issues affecting clean coal technology deployment

    Energy Technology Data Exchange (ETDEWEB)

    Miller, M.J. [Electric Power Research Inst., Palo Alto, CA (United States)

    1997-12-31

    The author outlines what he considers to be the key environmental issues affecting Clean Coal Technology (CCT) deployment both in the US and internationally. Since the international issues are difficult to characterize given different environmental drivers in various countries and regions, the primary focus of his remarks is on US deployment. However, he makes some general remarks, particularly regarding the environmental issues in developing vs. developed countries and how these issues may affect CCT deployment. Further, how environment affects deployment depends on which particular type of clean coal technology one is addressing. It is not the author`s intention to mention many specific technologies other than to use them for the purposes of example. He generally categorizes CCTs into four groups since environment is likely to affect deployment for each category somewhat differently. These four categories are: Precombustion technologies such as coal cleaning; Combustion technologies such as low NOx burners; Postcombustion technologies such as FGD systems and postcombustion NOx control; and New generation technologies such as gasification and fluidized bed combustion.

  4. Review Of Prevention Techniques For Denial Of Service DOS Attacks In Wireless Sensor Network

    Directory of Open Access Journals (Sweden)

    Poonam Rolla

    2015-08-01

    Full Text Available Wireless Sensor Networks comprised of several tiny sensor nodes which are densely deployed over the region to monitor the environmental conditions. These sensor nodes have certain design issues out of which security is the main predominant factor as it effects the whole lifetime of network. DDoS Distributed denial of service attack floods unnecessary packets in the sensor network. A review on DDoS attacks and their prevention techniques have been done in this paper.

  5. A Dynamic Processing System for Sensor Data in IoT

    OpenAIRE

    Li, Minbo; Liu, Yanling; Cai, Yuanfeng

    2015-01-01

    With the development of the Internet of Things (IoT for short), innumerable Wireless Sensor Networks (WSNs) are deployed to capture the information of environmental status in the surrounding physical environment. The data from WSNs, called sensor data, are generated in high frequency. Similar to data of other open-loop applications, for example, network monitoring data, sensor data are heterogeneous, redundant, real-time, massive, and streaming. Hence, sensor data cannot be treated as the IoT...

  6. Persistent Identifiers for Field Deployments: A Missing Link in the Provenance Chain

    Science.gov (United States)

    Arko, R. A.; Ji, P.; Fils, D.; Shepherd, A.; Chandler, C. L.; Lehnert, K.

    2016-12-01

    Research in the geosciences is characterized by a wide range of complex and costly field deployments including oceanographic cruises, submersible dives, drilling expeditions, seismic networks, geodetic campaigns, moored arrays, aircraft flights, and satellite missions. Each deployment typically produces a mix of sensor and sample data, spanning a period from hours to decades, that ultimately yields a long tail of post-field products and publications. Publishing persistent, citable identifiers for field deployments will facilitate 1) preservation and reuse of the original field data, 2) reproducibility of the resulting publications, and 3) recognition for both the facilities that operate the platforms and the investigators who secure funding for the experiments. In the ocean domain, sharing unique identifiers for field deployments is a familiar practice. For example, the Biological and Chemical Oceanography Data Management Office (BCO-DMO) routinely links datasets to cruise identifiers published by the Rolling Deck to Repository (R2R) program. In recent years, facilities have started to publish formal/persistent identifiers, typically Digital Object Identifiers (DOIs), for field deployments including seismic networks, oceanographic cruises, and moored arrays. For example, the EarthChem Library (ECL) publishes a DOI for each dataset which, if it derived from an oceanographic research cruise on a US vessel, is linked to a DOI for the cruise published by R2R. Work is underway to create similar links for the IODP JOIDES Resolution Science Operator (JRSO) and the Continental Scientific Drilling Coordination Office (CSDCO). We present results and lessons learned including a draft schema for publishing field deployments as DataCite DOI records; current practice for linking these DOIs with related identifiers such as Open Researcher and Contributor IDs (ORCIDs), Open Funder Registry (OFR) codes, and International Geo Sample Numbers (IGSNs); and consideration of other

  7. Guidesonde: Targeting meteorological dropsonde with optical and in-situ sensors, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — There exists a programmatic need across several government agencies for both UAV and manned aircraft to be able to deploy in-situ observation sensors within areas of...

  8. 5th International Workshop on Real-World Wireless Sensor Networks

    CERN Document Server

    Hu, Wen; Ferrari, Federico; Zimmerling, Marco; Mottola, Luca

    2014-01-01

    This edited book presents the results of the 5th Workshop on Real-world Wireless Sensor Networks (REALWSN). The purpose of this workshop  was to bring together researchers and practitioners working in the area of sensor networks, with focus on real-world experiments or deployments of wireless sensor networks. Included were, nonetheless, emerging forms of sensing such as those that leverage smart phones, Internet of Things, RFIDs, and robots. Indeed, when working with real-world experiments or deployments, many new or unforeseen issues may arise: the network environment may be composed of a variety of different technologies, leading to very heterogeneous network structures; software development for large scale networks poses new types of problems; the performance of prototype networks may differ significantly from the deployed system; whereas actual sensor network deployments may need a complex combination of autonomous and manual configuration. Furthermore, results obtained through simulation are typically n...

  9. Campaign monitoring of railroad bridges in high-speed rail shared corridors using wireless smart sensors.

    Science.gov (United States)

    2015-06-01

    This research project used wireless smart sensors to develop a cost-effective and practical portable structural health monitoring : system for railroad bridges in North America. The system is designed for periodic deployment rather than as a permanen...

  10. A Method to Estimate Local Towed Array Angles Using Flush Mounted Hot Film Wall Shear Sensors

    National Research Council Canada - National Science Library

    Keith, William L; Cipolla, Kimberly M

    2008-01-01

    A towed array is provided with hot-film sensors and anemometer circuitry to calculate the angle of inclination of the towed array in real time during deployment of the towed array in a sea water environment...

  11. Multi-use Passive RFID Sensor Tag System for NASA, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — This proposal will provide NASA with a family of UHF RFID sensor tags and system components supporting very reliable, robust, convenient and economical deployment...

  12. Service Creation and Deployment in Converged Networks

    DEFF Research Database (Denmark)

    Soler, José

    for these experiences is the transition of telecommunication (telephony) networks from circuit switched based systems towards packet based ones. The text of this monograph proceeds, unaltered for the most, from the author’s PhD thesis “Framework for Deployment of Advanced Telecommunication Services in Current......This monograph (Early Experiences related to Service Creation & Deployment in Converged Networks) presents different experiences related to architectures and mechanisms for deployment of telephony services, understood as especial features complementing the basic voice service. The context...... and Future Converged Networks”, carried out at the Technical University of Denmark in the period [April 2002-April 2005]. Even though the technologies presented in the text have evolved from that period until now, the presented scenarios and setups are still valid as interesting initial steps in the realm....

  13. Deploying Embodied AI into Virtual Worlds

    Science.gov (United States)

    Burden, David J. H.

    The last two years have seen the start of commercial activity within virtual worlds. Unlike computer games where Non-Player-Character avatars are common, in most virtual worlds they are the exception — and until recently in Second Life they were non-existent. However there is real commercial scope for Als in these worlds — in roles from virtual sales staff and tutors to personal assistants. Deploying an embodied AI into a virtual world offers a unique opportunity to evaluate embodied Als, and to develop them within an environment where human and computer are on almost equal terms. This paper presents an architecture being used for the deployment of chatbot driven avatars within the Second Life virtual world, looks at the challenges of deploying an AI within such a virtual world, the possible implications for the Turing Test, and identifies research directions for the future.

  14. Deployment Instabilities of Lobed-Pumpkin Balloon

    Science.gov (United States)

    Nakashino, Kyoichi

    A lobed-pumpkin balloon, currently being developed in ISAS/JAXA as well as in NASA, is a promising vehicle for long duration scientific observations in the stratosphere. Recent ground and flight experiments, however, have revealed that the balloon has deployment instabilities under certain conditions. In order to overcome the instability problems, a next generation SPB called 'tawara' type balloon has been proposed, in which an additional cylindrical part is appended to the standard lobed-pumpkin balloon. The present study investigates the deployment stability of tawara type SPB in comparison to that of standard lobed-pumpkin SPB through eigenvalue analysis on the basis of finite element methods. Our numerical results show that tawara type SPB enjoys excellent deployment performance over the standard lobed-pumpkin SPBs.

  15. Compressed sensing embedded in an operational wireless sensor network to achieve energy efficiency in long-term monitoring applications

    International Nuclear Information System (INIS)

    O’Connor, S M; Lynch, J P; Gilbert, A C

    2014-01-01

    Compressed sensing (CS) is a powerful new data acquisition paradigm that seeks to accurately reconstruct unknown sparse signals from very few (relative to the target signal dimension) random projections. The specific objective of this study is to save wireless sensor energy by using CS to simultaneously reduce data sampling rates, on-board storage requirements, and communication data payloads. For field-deployed low power wireless sensors that are often operated with limited energy sources, reduced communication translates directly into reduced power consumption and improved operational reliability. In this study, acceleration data from a multi-girder steel-concrete deck composite bridge are processed for the extraction of mode shapes. A wireless sensor node previously designed to perform traditional uniform, Nyquist rate sampling is modified to perform asynchronous, effectively sub-Nyquist rate sampling. The sub-Nyquist data are transmitted off-site to a computational server for reconstruction using the CoSaMP matching pursuit recovery algorithm and further processed for extraction of the structure’s mode shapes. The mode shape metric used for reconstruction quality is the modal assurance criterion (MAC), an indicator of the consistency between CS and traditional Nyquist acquired mode shapes. A comprehensive investigation of modal accuracy from a dense set of acceleration response data reveals that MAC values above 0.90 are obtained for the first four modes of a bridge structure when at least 20% of the original signal is sampled using the CS framework. Reduced data collection, storage and communication requirements are found to lead to substantial reductions in the energy requirements of wireless sensor networks at the expense of modal accuracy. Specifically, total energy reductions of 10–60% can be obtained for a sensor network with 10–100 sensor nodes, respectively. The reduced energy requirements of the CS sensor nodes are shown to directly result in

  16. Optischer Sensor

    OpenAIRE

    Brandenburg, A.; Hutter, F.; Edelhaeuser, R.

    1992-01-01

    WO 2010040565 A1 UPAB: 20100506 NOVELTY - The integrated optical sensor comprises a first waveguide (4), a second waveguide (5) optically coupled to the first waveguide via a directional coupler, a substrate, which carries the first and the second waveguides, a single waveguide coupled with a light source, and an output waveguide coupled with a light-sensitive element. The sensor has a functional surface in the region of the directional coupler for depositing or deposition of the substance to...

  17. Wireless sensor

    Science.gov (United States)

    Lamberti, Vincent E.; Howell, JR, Layton N.; Mee, David K.; Sepaniak, Michael J.

    2016-02-09

    Disclosed is a sensor for detecting a target material. The sensor includes a ferromagnetic metal and a molecular recognition reagent coupled to the ferromagnetic metal. The molecular recognition reagent is operable to expand upon exposure to vapor or liquid from the target material such that the molecular recognition reagent changes a tensile stress upon the ferromagnetic metal. The target material is detected based on changes in the magnetic switching characteristics of the ferromagnetic metal caused by the changes in the tensile stress.

  18. Comparing post-deployment mental health services utilization in soldiers deployed to Balkan, Iraq and Afghanistan

    DEFF Research Database (Denmark)

    Madsen, T; Sadowa Vedtofte, M; Nordentoft, M

    2017-01-01

    OBJECTIVE: Insight on how different missions have impacted rates of mental health service (MHS) utilization is unexplored. We compared postdeployment MHS utilization in a national cohort of first-time deployed to missions in Balkan, Iraq, and Afghanistan respectively. METHODS: A prospective...... national cohort study of 13 246 first-time deployed in the period 1996 through 2012 to missions in Balkan area, Iraq, or Afghanistan respectively. Soldiers 'MHS utilization was also compared with a 5:1 sex-, age-, and calendar year-matched never-deployed background population. Postdeployment utilization...... of psychotropics. RESULTS: Utilizing of psychiatric outpatient services and psychotropics was significantly higher in first-time deployed to Iraq and Afghanistan compared with deployed to Balkan. However, the rate of postdeployment admission to psychiatric hospital did not differ between missions. Postdeployment...

  19. Industrial deployment of system engineering methods

    CERN Document Server

    Romanovsky, Alexander

    2013-01-01

    A formal method is not the main engine of a development process, its contribution is to improve system dependability by motivating formalisation where useful. This book summarizes the results of the DEPLOY research project on engineering methods for dependable systems through the industrial deployment of formal methods in software development. The applications considered were in automotive, aerospace, railway, and enterprise information systems, and microprocessor design.  The project introduced a formal method, Event-B, into several industrial organisations and built on the lessons learned to

  20. Challenges to Deploy Service Design in Organizations

    DEFF Research Database (Denmark)

    Akasaka, Fumiya; Ohno, Takehiko; Jensen, Mika Yasuoka

    2016-01-01

    More and more companies are applying service design approaches to develop services and products. Not every project, however, has achieved its goals. In many cases, difficulties arise from organizational issues such as organization structure and evaluation system. In this research, we held workshops...... where success and failure factors of service design projects in organization are presented. By analysing the results, we construct a model that explains the “difficulties of deploying the service design approach in organization.” On the basis of the model, this paper discusses the challenges...... to the deployment of the service design approach in organizations....

  1. Distributed Sensor Fusion for Scalar Field Mapping Using Mobile Sensor Networks.

    Science.gov (United States)

    La, Hung Manh; Sheng, Weihua

    2013-04-01

    In this paper, autonomous mobile sensor networks are deployed to measure a scalar field and build its map. We develop a novel method for multiple mobile sensor nodes to build this map using noisy sensor measurements. Our method consists of two parts. First, we develop a distributed sensor fusion algorithm by integrating two different distributed consensus filters to achieve cooperative sensing among sensor nodes. This fusion algorithm has two phases. In the first phase, the weighted average consensus filter is developed, which allows each sensor node to find an estimate of the value of the scalar field at each time step. In the second phase, the average consensus filter is used to allow each sensor node to find a confidence of the estimate at each time step. The final estimate of the value of the scalar field is iteratively updated during the movement of the mobile sensors via weighted average. Second, we develop the distributed flocking-control algorithm to drive the mobile sensors to form a network and track the virtual leader moving along the field when only a small subset of the mobile sensors know the information of the leader. Experimental results are provided to demonstrate our proposed algorithms.

  2. Simulation of bubbly flow in vertical pipes by coupling Lagrangian and Eulerian models with 3D random walks models: Validation with experimental data using multi-sensor conductivity probes and Laser Doppler Anemometry

    Energy Technology Data Exchange (ETDEWEB)

    Munoz-Cobo, Jose L., E-mail: jlcobos@iqn.upv.es [Instituto de Ingenieria Energetica, Universidad Politecnica de Valencia, Valencia (Spain); Chiva, Sergio [Department of Mechanical Engineering and Construction, Universitat Jaume I, Castellon (Spain); Essa, Mohamed Ali Abd El Aziz [Instituto de Ingenieria Energetica, Universidad Politecnica de Valencia, Valencia (Spain); Mendes, Santos [Facultad de Ingenieria Mecanica y Electrica, Universidad Autonoma de Nuevo Leon (Mexico)

    2012-01-15

    Highlights: Black-Right-Pointing-Pointer We have simulated bubbly flow in vertical pipes by coupling a Lagrangian model to an Eulerian one, and to a 3D random walk model. Black-Right-Pointing-Pointer A set of experiments in a vertical column with isothermal co-current two phase flow have been performed and used to validate the previous model. Black-Right-Pointing-Pointer We have investigated the influence of the turbulence induced by the bubbles on the results. Black-Right-Pointing-Pointer Comparison of experimental and computed results has been performed for different boundary conditions. - Abstract: A set of two phase flow experiments for different conditions ranging from bubbly flow to cap/slug flow have been performed under isothermal concurrent upward air-water flow conditions in a vertical column of 3 m height. Special attention in these experiments was devoted to the transition from bubbly to cap/slug flow. The interfacial velocity of the bubbles and the void fraction distribution was obtained using 2 and 4 sensors conductivity probes. Numerical simulations of these experiments for bubbly flow conditions were performed by coupling a Lagrangian code with an Eulerian one. The first one tracks the 3D motion of the individual bubbles in cylindrical coordinates (r, {phi}, z) inside the fluid field under the action of the following forces: buoyancy, drag, lift, wall lubrication. Also we have incorporated a 3D stochastic differential equation model to account for the random motion of the individual bubbles in the turbulent velocity field of the carrier liquid. Also we have considered the deformations undergone by the bubbles when they touch the walls of the pipe and are compressed until they rebound. The velocity and turbulence fields of the liquid phase were computed by solving the time dependent conservation equations in its Reynolds Averaged Transport Equation form (RANS). The turbulent kinetic energy k, and the dissipation rate {epsilon} transport equations

  3. Simulation of bubbly flow in vertical pipes by coupling Lagrangian and Eulerian models with 3D random walks models: Validation with experimental data using multi-sensor conductivity probes and Laser Doppler Anemometry

    International Nuclear Information System (INIS)

    Muñoz-Cobo, José L.; Chiva, Sergio; Essa, Mohamed Ali Abd El Aziz; Mendes, Santos

    2012-01-01

    Highlights: ► We have simulated bubbly flow in vertical pipes by coupling a Lagrangian model to an Eulerian one, and to a 3D random walk model. ► A set of experiments in a vertical column with isothermal co-current two phase flow have been performed and used to validate the previous model. ► We have investigated the influence of the turbulence induced by the bubbles on the results. ► Comparison of experimental and computed results has been performed for different boundary conditions. - Abstract: A set of two phase flow experiments for different conditions ranging from bubbly flow to cap/slug flow have been performed under isothermal concurrent upward air–water flow conditions in a vertical column of 3 m height. Special attention in these experiments was devoted to the transition from bubbly to cap/slug flow. The interfacial velocity of the bubbles and the void fraction distribution was obtained using 2 and 4 sensors conductivity probes. Numerical simulations of these experiments for bubbly flow conditions were performed by coupling a Lagrangian code with an Eulerian one. The first one tracks the 3D motion of the individual bubbles in cylindrical coordinates (r, φ, z) inside the fluid field under the action of the following forces: buoyancy, drag, lift, wall lubrication. Also we have incorporated a 3D stochastic differential equation model to account for the random motion of the individual bubbles in the turbulent velocity field of the carrier liquid. Also we have considered the deformations undergone by the bubbles when they touch the walls of the pipe and are compressed until they rebound. The velocity and turbulence fields of the liquid phase were computed by solving the time dependent conservation equations in its Reynolds Averaged Transport Equation form (RANS). The turbulent kinetic energy k, and the dissipation rate ε transport equations were simultaneously solved using the k, epsilon model in a (r, z) grid by the finite volume method and the

  4. Sensor technology for smart homes.

    Science.gov (United States)

    Ding, Dan; Cooper, Rory A; Pasquina, Paul F; Fici-Pasquina, Lavinia

    2011-06-01

    A smart home is a residence equipped with technology that observes the residents and provides proactive services. Most recently, it has been introduced as a potential solution to support independent living of people with disabilities and older adults, as well as to relieve the workload from family caregivers and health providers. One of the key supporting features of a smart home is its ability to monitor the activities of daily living and safety of residents, and in detecting changes in their daily routines. With the availability of inexpensive low-power sensors, radios, and embedded processors, current smart homes are typically equipped with a large amount of networked sensors which collaboratively process and make deductions from the acquired data on the state of the home as well as the activities and behaviors of its residents. This article reviews sensor technology used in smart homes with a focus on direct environment sensing and infrastructure mediated sensing. The article also points out the strengths and limitations of different sensor technologies, as well as discusses challenges and opportunities from clinical, technical, and ethical perspectives. It is recommended that sensor technologies for smart homes address actual needs of all stake holders including end users, their family members and caregivers, and their doctors and therapists. More evidence on the appropriateness, usefulness, and cost benefits analysis of sensor technologies for smart homes is necessary before these sensors should be widely deployed into real-world residential settings and successfully integrated into everyday life and health care services. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  5. Applying Sensor Web Technology to Marine Sensor Data

    Science.gov (United States)

    Jirka, Simon; del Rio, Joaquin; Mihai Toma, Daniel; Nüst, Daniel; Stasch, Christoph; Delory, Eric

    2015-04-01

    SWE specifications that provide stricter guidance how these standards shall be applied to marine data (e.g. SensorML 2.0 profiles stating which metadata elements are mandatory building upon the ESONET Sensor Registry developments, etc.). Within the NeXOS project the presented architecture is implemented as a set of open source components. These implementations can be re-used by all interested scientists and data providers needing tools for publishing or consuming oceanographic sensor data. In further projects such as the European project FixO3 (Fixed-point Open Ocean Observatories), these software development activities are complemented with additional efforts to provide guidance how Sensor Web technology can be applied in an efficient manner. This way, not only software components are made available but also documentation and information resources that help to understand which types of Sensor Web deployments are best suited to fulfil different types of user requirements.

  6. A new energy-efficient MAC protocol with noise-based transmitted-reference modulation for wireless sensor network

    NARCIS (Netherlands)

    Morshed, S.; Heijenk, Geert; Meijerink, Arjan; Ye, D.; van der Zee, Ronan A.R.; Bentum, Marinus Jan

    2013-01-01

    Energy-constrained behavior of sensor nodes is one of the most important criteria for successful deployment of wireless sensor networks. The medium access control (MAC) protocol determines to a large extent the time a sensor node transceiver spends listening or transmitting, and hence the energy

  7. TR-MAC: an energy-efficient MAC protocol for wireless sensor networks exploiting noise-based transmitted reference modulation

    NARCIS (Netherlands)

    Morshed, S.; Dimitrova, D.C.; Brogle, M.; Braun, T.; Heijenk, Gerhard J.

    Energy-constrained behavior of sensor nodes is one of the most important criteria for successful deployment of wireless sensor net- works. The medium access control (MAC) protocol determines the time a sensor node transceiver spends listening or transmitting, and hence the energy consumption of the

  8. Evaluation of 90nm 6T-SRAM as physical unclonable function for secure key generation in wireless sensor nodes

    NARCIS (Netherlands)

    Selimis, G.; Konijnenburg, M.; Ashouei, M.; Huisken, J.; de Groot, H.; van der Leest, V.; Schrijen, G.-J.; van Hulst, M.; Tuyls, P.

    2011-01-01

    Due to the unattended nature of WSN (Wireless Sensor Network) deployment, each sensor can be subject to physical capture, cloning and unauthorized device alteration. In this paper, we use the embedded SRAM, often available on a wireless sensor node, for secure data (cryptographic keys, IDs)

  9. Decentralized Sensor Fusion for Ubiquitous Networking Robotics in Urban Areas

    Science.gov (United States)

    Sanfeliu, Alberto; Andrade-Cetto, Juan; Barbosa, Marco; Bowden, Richard; Capitán, Jesús; Corominas, Andreu; Gilbert, Andrew; Illingworth, John; Merino, Luis; Mirats, Josep M.; Moreno, Plínio; Ollero, Aníbal; Sequeira, João; Spaan, Matthijs T.J.

    2010-01-01

    In this article we explain the architecture for the environment and sensors that has been built for the European project URUS (Ubiquitous Networking Robotics in Urban Sites), a project whose objective is to develop an adaptable network robot architecture for cooperation between network robots and human beings and/or the environment in urban areas. The project goal is to deploy a team of robots in an urban area to give a set of services to a user community. This paper addresses the sensor architecture devised for URUS and the type of robots and sensors used, including environment sensors and sensors onboard the robots. Furthermore, we also explain how sensor fusion takes place to achieve urban outdoor execution of robotic services. Finally some results of the project related to the sensor network are highlighted. PMID:22294927

  10. Decentralized Sensor Fusion for Ubiquitous Networking Robotics in Urban Areas

    Directory of Open Access Journals (Sweden)

    Aníbal Ollero

    2010-03-01

    Full Text Available In this article we explain the architecture for the environment and sensors that has been built for the European project URUS (Ubiquitous Networking Robotics in Urban Sites, a project whose objective is to develop an adaptable network robot architecture for cooperation between network robots and human beings and/or the environment in urban areas. The project goal is to deploy a team of robots in an urban area to give a set of services to a user community. This paper addresses the sensor architecture devised for URUS and the type of robots and sensors used, including environment sensors and sensors onboard the robots. Furthermore, we also explain how sensor fusion takes place to achieve urban outdoor execution of robotic services. Finally some results of the project related to the sensor network are highlighted.

  11. Analysis of the impact of data correlation on adaptive sampling in Wireless Sensor Networks

    NARCIS (Netherlands)

    Masoum, Alireza; Meratnia, Nirvana; Havinga, Paul J.M.

    Wireless Sensor Networks (WSNs) are often densely deployed to monitor a physical phenomenon, whose nature often exhibits temporal correlation in sequential readings. Such a dense deployment results in high correlation of sensing data in the space domain. Since WSNs suffer from sever resource

  12. Dynamic curvature sensing employing ionic-polymer–metal composite sensors

    International Nuclear Information System (INIS)

    Bahramzadeh, Yousef; Shahinpoor, Mohsen

    2011-01-01

    A dynamic curvature sensor is presented based on ionic-polymer–metal composite (IPMC) for curvature monitoring of deployable/inflatable dynamic space structures. Monitoring the curvature variation is of high importance in various engineering structures including shape monitoring of deployable/inflatable space structures in which the structural boundaries undergo a dynamic deployment process. The high sensitivity of IPMCs to the applied deformations as well as its flexibility make IPMCs a promising candidate for sensing of dynamic curvature changes. Herein, we explore the dynamic response of an IPMC sensor strip with respect to controlled curvature deformations subjected to different forms of input functions. Using a specially designed experimental setup, the voltage recovery effect, phase delay, and rate dependency of the output voltage signal of an IPMC curvature sensor are analyzed. Experimental results show that the IPMC sensor maintains the linearity, sensitivity, and repeatability required for curvature sensing. Besides, in order to describe the dynamic phenomena such as the rate dependency of the IPMC sensor, a chemo-electro-mechanical model based on the Poisson–Nernst–Planck (PNP) equation for the kinetics of ion diffusion is presented. By solving the governing partial differential equations the frequency response of the IPMC sensor is derived. The physical model is able to describe the dynamic properties of the IPMC sensor and the dependency of the signal on rate of excitations

  13. Data retrieval time for energy harvesting wireless sensors

    NARCIS (Netherlands)

    Mitici, M.A.; Goseling, Jasper; de Graaf, Maurits; Boucherie, Richardus J.

    2015-01-01

    We consider the problem of retrieving a reliable estimate of an attribute monitored by a wireless sensor network, where the sensors harvest energy from the environment independently, at random. Each sensor stores the harvested energy in batteries of limited capacity. Moreover, provided they have

  14. Randomized Search Strategies With Imperfect Sensors

    National Research Council Canada - National Science Library

    Gage, Douglas W

    1993-01-01

    .... An important class of coverage applications are those that involve a search, in which a number of searching elements move about within a prescribed search area in order to find one or more target...

  15. Iron Status of Deployed Military Members

    Science.gov (United States)

    2017-01-04

    ready force Deploy with and care for the warrior Care for all entrusted to our care Nursing Competencies and Practice: Patient outcomes...duties, physical activities, iron intake through diet ). This additional information would improve the ability to determine factors associated with

  16. Microsoft System Center Configuration Manager advanced deployment

    CERN Document Server

    Coupland, Martyn

    2014-01-01

    If you are an experienced Configuration Manager administrator looking to advance your career or get more from your current environment, then this book is ideal for you. Prior experience of deploying and managing a Configuration Manager site would be helpful in following the examples throughout this book.

  17. Military Deployment and Elementary Student Achievement

    Science.gov (United States)

    Phelps, Terri; Dunham, Mardis; Lyons, Robert

    2010-01-01

    This study investigated the impact that military deployment has upon academic achievement of elementary school students. TerraNova test scores of 137 fourth and fifth grade students in two elementary schools with a high proportion of military dependent children were examined for two consecutive years. Although the academic test performance fell…

  18. 77 FR 36903 - Accelerating Broadband Infrastructure Deployment

    Science.gov (United States)

    2012-06-20

    ... the Nation's global competitiveness in the 21st century, driving job creation, promoting innovation, and expanding markets for American businesses. Broadband access also affords public safety agencies... infrastructure has been deployed in a vast majority of communities across the country, today too many areas still...

  19. Guam: U.S. Defense Deployments

    Science.gov (United States)

    2013-11-15

    August 8, 2013; Ta Kung Pao, August 12, 2013. 22 Sam Kim, “N. Korea Deploys Medium-Range Missiles, Bolsters Special Forces,” Yonhap, Seoul, February 23...building up its submarine force (both nuclear-powered and diesel-electric). In November 2004, the PLA Navy sent a Han -class nuclear attack submarine

  20. Proximity sensor system development. CRADA final report

    International Nuclear Information System (INIS)

    Haley, D.C.; Pigoski, T.M.

    1998-01-01

    Lockheed Martin Energy Research Corporation (LMERC) and Merritt Systems, Inc. (MSI) entered into a Cooperative Research and Development Agreement (CRADA) for the development and demonstration of a compact, modular proximity sensing system suitable for application to a wide class of manipulator systems operated in support of environmental restoration and waste management activities. In teleoperated modes, proximity sensing provides the manipulator operator continuous information regarding the proximity of the manipulator to objects in the workspace. In teleoperated and robotic modes, proximity sensing provides added safety through the implementation of active whole arm collision avoidance capabilities. Oak Ridge National Laboratory (ORNL), managed by LMERC for the United States Department of Energy (DOE), has developed an application specific integrated circuit (ASIC) design for the electronics required to support a modular whole arm proximity sensing system based on the use of capacitive sensors developed at Sandia National Laboratories. The use of ASIC technology greatly reduces the size of the electronics required to support the selected sensor types allowing deployment of many small sensor nodes over a large area of the manipulator surface to provide maximum sensor coverage. The ASIC design also provides a communication interface to support sensor commands from and sensor data transmission to a distributed processing system which allows modular implementation and operation of the sensor system. MSI is a commercial small business specializing in proximity sensing systems based upon infrared and acoustic sensors

  1. Proximity sensor system development. CRADA final report

    Energy Technology Data Exchange (ETDEWEB)

    Haley, D.C. [Oak Ridge National Lab., TN (United States); Pigoski, T.M. [Merrit Systems, Inc. (United States)

    1998-01-01

    Lockheed Martin Energy Research Corporation (LMERC) and Merritt Systems, Inc. (MSI) entered into a Cooperative Research and Development Agreement (CRADA) for the development and demonstration of a compact, modular proximity sensing system suitable for application to a wide class of manipulator systems operated in support of environmental restoration and waste management activities. In teleoperated modes, proximity sensing provides the manipulator operator continuous information regarding the proximity of the manipulator to objects in the workspace. In teleoperated and robotic modes, proximity sensing provides added safety through the implementation of active whole arm collision avoidance capabilities. Oak Ridge National Laboratory (ORNL), managed by LMERC for the United States Department of Energy (DOE), has developed an application specific integrated circuit (ASIC) design for the electronics required to support a modular whole arm proximity sensing system based on the use of capacitive sensors developed at Sandia National Laboratories. The use of ASIC technology greatly reduces the size of the electronics required to support the selected sensor types allowing deployment of many small sensor nodes over a large area of the manipulator surface to provide maximum sensor coverage. The ASIC design also provides a communication interface to support sensor commands from and sensor data transmission to a distributed processing system which allows modular implementation and operation of the sensor system. MSI is a commercial small business specializing in proximity sensing systems based upon infrared and acoustic sensors.

  2. A key design to prolong lifetime of wireless sensor network

    International Nuclear Information System (INIS)

    Qiu, Bo; Chen, XiQiu; Wu, Qi

    2016-01-01

    In order to solve the contradiction between the connectivity of the wireless sensor network and the key storage consumption, under the premise of reducing network storage consumption, the key pre-distribution management scheme with higher connectivity rate is proposed using the hexagonal network deployment information, which adopts the idea of the matrix space for the square deployment information strategy to reduce the burden of the network storage. Ability against the capture attack is improved obviously. The results show that contradiction between the network connectivity rate and the energy consumption has a better solution, and the proposed algorithm is suitable for the wireless sensor networks of energy limited.

  3. Link-quality measurement and reporting in wireless sensor networks.

    Science.gov (United States)

    Chehri, Abdellah; Jeon, Gwanggil; Choi, Byoungjo

    2013-03-04

    Wireless Sensor networks (WSNs) are created by small hardware devices that possess the necessary functionalities to measure and exchange a variety of environmental data in their deployment setting. In this paper, we discuss the experiments in deploying a testbed as a first step towards creating a fully functional heterogeneous wireless network-based underground monitoring system. The system is mainly composed of mobile and static ZigBee nodes, which are deployed on the underground mine galleries for measuring ambient temperature. In addition, we describe the measured results of link characteristics such as received signal strength, latency and throughput for different scenarios.

  4. Link-Quality Measurement and Reporting in Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Byoungjo Choi

    2013-03-01

    Full Text Available Wireless Sensor networks (WSNs are created by small hardware devices that possess the necessary functionalities to measure and exchange a variety of environmental data in their deployment setting. In this paper, we discuss the experiments in deploying a testbed as a first step towards creating a fully functional heterogeneous wireless network-based underground monitoring system. The system is mainly composed of mobile and static ZigBee nodes, which are deployed on the underground mine galleries for measuring ambient temperature. In addition, we describe the measured results of link characteristics such as received signal strength, latency and throughput for different scenarios.

  5. Very Low Head Turbine Deployment in Canada

    International Nuclear Information System (INIS)

    Kemp, P; Williams, C; Sasseville, Remi; Anderson, N

    2014-01-01

    The Very Low Head (VLH) turbine is a recent turbine technology developed in Europe for low head sites in the 1.4 - 4.2 m range. The VLH turbine is primarily targeted for installation at existing hydraulic structures to provide a low impact, low cost, yet highly efficient solution. Over 35 VLH turbines have been successfully installed in Europe and the first VLH deployment for North America is underway at Wasdell Falls in Ontario, Canada. Deployment opportunities abound in Canada with an estimated 80,000 existing structures within North America for possible low-head hydro development. There are several new considerations and challenges for the deployment of the VLH turbine technology in Canada in adapting to the hydraulic, environmental, electrical and social requirements. Several studies were completed to determine suitable approaches and design modifications to mitigate risk and confirm turbine performance. Diverse types of existing weirs and spillways pose certain hydraulic design challenges. Physical and numerical modelling of the VLH deployment alternatives provided for performance optimization. For this application, studies characterizing the influence of upstream obstacles using water tunnel model testing as well as full-scale prototype flow dynamics testing were completed. A Cold Climate Adaptation Package (CCA) was developed to allow year-round turbine operation in ice covered rivers. The CCA package facilitates turbine extraction and accommodates ice forces, frazil ice, ad-freezing and cold temperatures that are not present at the European sites. The Permanent Magnet Generator (PMG) presents some unique challenges in meeting Canadian utility interconnection requirements. Specific attention to the frequency driver control and protection requirements resulted in a driver design with greater over-voltage capability for the PMG as well as other key attributes. Environmental studies in Europe included fish friendliness testing comprised of multiple in

  6. Very Low Head Turbine Deployment in Canada

    Science.gov (United States)

    Kemp, P.; Williams, C.; Sasseville, Remi; Anderson, N.

    2014-03-01

    The Very Low Head (VLH) turbine is a recent turbine technology developed in Europe for low head sites in the 1.4 - 4.2 m range. The VLH turbine is primarily targeted for installation at existing hydraulic structures to provide a low impact, low cost, yet highly efficient solution. Over 35 VLH turbines have been successfully installed in Europe and the first VLH deployment for North America is underway at Wasdell Falls in Ontario, Canada. Deployment opportunities abound in Canada with an estimated 80,000 existing structures within North America for possible low-head hydro development. There are several new considerations and challenges for the deployment of the VLH turbine technology in Canada in adapting to the hydraulic, environmental, electrical and social requirements. Several studies were completed to determine suitable approaches and design modifications to mitigate risk and confirm turbine performance. Diverse types of existing weirs and spillways pose certain hydraulic design challenges. Physical and numerical modelling of the VLH deployment alternatives provided for performance optimization. For this application, studies characterizing the influence of upstream obstacles using water tunnel model testing as well as full-scale prototype flow dynamics testing were completed. A Cold Climate Adaptation Package (CCA) was developed to allow year-round turbine operation in ice covered rivers. The CCA package facilitates turbine extraction and accommodates ice forces, frazil ice, ad-freezing and cold temperatures that are not present at the European sites. The Permanent Magnet Generator (PMG) presents some unique challenges in meeting Canadian utility interconnection requirements. Specific attention to the frequency driver control and protection requirements resulted in a driver design with greater over-voltage capability for the PMG as well as other key attributes. Environmental studies in Europe included fish friendliness testing comprised of multiple in

  7. Sensor Technologies for Intelligent Transportation Systems.

    Science.gov (United States)

    Guerrero-Ibáñez, Juan; Zeadally, Sherali; Contreras-Castillo, Juan

    2018-04-16

    Modern society faces serious problems with transportation systems, including but not limited to traffic congestion, safety, and pollution. Information communication technologies have gained increasing attention and importance in modern transportation systems. Automotive manufacturers are developing in-vehicle sensors and their applications in different areas including safety, traffic management, and infotainment. Government institutions are implementing roadside infrastructures such as cameras and sensors to collect data about environmental and traffic conditions. By seamlessly integrating vehicles and sensing devices, their sensing and communication capabilities can be leveraged to achieve smart and intelligent transportation systems. We discuss how sensor technology can be integrated with the transportation infrastructure to achieve a sustainable Intelligent Transportation System (ITS) and how safety, traffic control and infotainment applications can benefit from multiple sensors deployed in different elements of an ITS. Finally, we discuss some of the challenges that need to be addressed to enable a fully operational and cooperative ITS environment.

  8. Sensor Technologies for Intelligent Transportation Systems

    Science.gov (United States)

    Guerrero-Ibáñez, Juan; Zeadally, Sherali

    2018-01-01

    Modern society faces serious problems with transportation systems, including but not limited to traffic congestion, safety, and pollution. Information communication technologies have gained increasing attention and importance in modern transportation systems. Automotive manufacturers are developing in-vehicle sensors and their applications in different areas including safety, traffic management, and infotainment. Government institutions are implementing roadside infrastructures such as cameras and sensors to collect data about environmental and traffic conditions. By seamlessly integrating vehicles and sensing devices, their sensing and communication capabilities can be leveraged to achieve smart and intelligent transportation systems. We discuss how sensor technology can be integrated with the transportation infrastructure to achieve a sustainable Intelligent Transportation System (ITS) and how safety, traffic control and infotainment applications can benefit from multiple sensors deployed in different elements of an ITS. Finally, we discuss some of the challenges that need to be addressed to enable a fully operational and cooperative ITS environment. PMID:29659524

  9. Sensor Technologies for Intelligent Transportation Systems

    Directory of Open Access Journals (Sweden)

    Juan Guerrero-Ibáñez

    2018-04-01

    Full Text Available Modern society faces serious problems with transportation systems, including but not limited to traffic congestion, safety, and pollution. Information communication technologies have gained increasing attention and importance in modern transportation systems. Automotive manufacturers are developing in-vehicle sensors and their applications in different areas including safety, traffic management, and infotainment. Government institutions are implementing roadside infrastructures such as cameras and sensors to collect data about environmental and traffic conditions. By seamlessly integrating vehicles and sensing devices, their sensing and communication capabilities can be leveraged to achieve smart and intelligent transportation systems. We discuss how sensor technology can be integrated with the transportation infrastructure to achieve a sustainable Intelligent Transportation System (ITS and how safety, traffic control and infotainment applications can benefit from multiple sensors deployed in different elements of an ITS. Finally, we discuss some of the challenges that need to be addressed to enable a fully operational and cooperative ITS environment.

  10. Highly-hermetic feedthrough fiber pigtailed circular TO-can electro-optic sensor for avionics applications

    Science.gov (United States)

    Lauzon, Jocelyn; Leduc, Lorrain; Bessette, Daniel; Bélanger, Nicolas

    2012-06-01

    Electro-optic sensors made of lasers or photodetectors assemblies can be associated with a window interface. In order to use these sensors in an avionics application, this interface has to be set on the periphery of the aircraft. This creates constraints on both the position/access of the associated electronics circuit card and the aircraft fuselage. Using an optical fiber to guide the light signal to a sensor being situated inside the aircraft where electronics circuit cards are deployed is an obvious solution that can be readily available. Fiber collimators that adapt to circular TO-can type window sensors do exist. However, they are bulky, add weight to the sensor and necessitate regular maintenance of the optical interface since both the sensor window and the collimator end-face are unprotected against contamination. Such maintenance can be complex since the access to the electronics circuit card, where the sensor is sitting, is usually difficult. This interface alignment can also be affected by vibrations and mechanical shocks, thus impacting sensor performances. As a solution to this problem, we propose a highly-hermetic feedthrough fiber pigtailed circular TO-can package. The optical element to optical fiber interface being set inside the hermetic package, there is no risk of contamination and thus, such a component does not require any maintenance. The footprint of these sensors being identical to their window counterparts, they offer drop-in replacement opportunities. Moreover, we have validated such packaged electro-optic sensors can be made to operate between -55 to 115°C, sustain 250 temperature cycles, 1500G mechanical shocks, 20Grms random vibrations without any performance degradations. Their water content is much smaller than the 0.5% limit set by MIL-STD-883, Method 1018. They have also been verified to offer a fiber pigtail strain relief resistance over 400g. Depending on the electronics elements inside these sensors, they can be made to have a

  11. Fatigue damage sensor and substantitation of its application. Communication 2

    Energy Technology Data Exchange (ETDEWEB)

    Troshchenko, V T; Bojko, V I

    1985-01-01

    Block and random loading is studied for its effect on sensor readings. It is established that variation of electric sensor conductivity for these conditions does not depend on the loading prehistory and may be calculated according to the sensor test results at a regular loading. A general scheme of the sensor application is considered for determining residual part life with allowance for the factors. Effect on a part fatigue resistance when operating conditions of the loading are characterized by a stationary random process. Particular cases of the sensor application are considered coming out from a common scheme.

  12. UAV-Assisted Dynamic Clustering of Wireless Sensor Networks for Crop Health Monitoring.

    Science.gov (United States)

    Uddin, Mohammad Ammad; Mansour, Ali; Jeune, Denis Le; Ayaz, Mohammad; Aggoune, El-Hadi M

    2018-02-11

    In this study, a crop health monitoring system is developed by using state of the art technologies including wireless sensors and Unmanned Aerial Vehicles (UAVs). Conventionally data is collected from sensor nodes either by fixed base stations or mobile sinks. Mobile sinks are considered a better choice nowadays due to their improved network coverage and energy utilization. Usually, the mobile sink is used in two ways: either it goes for random walk to find the scattered nodes and collect data, or follows a pre-defined path established by the ground network/clusters. Neither of these options is suitable in our scenario due to the factors like dynamic data collection, the strict targeted area required to be scanned, unavailability of a large number of nodes, dynamic path of the UAV, and most importantly, none of these are known in advance. The contribution of this paper is the formation of dynamic runtime clusters of field sensors by considering the above mentioned factors. Furthermore a mechanism (Bayesian classifier) is defined to select best node as cluster head. The proposed system is validated through simulation results, lab and infield experiments using concept devices. The obtained results are encouraging, especially in terms of deployment time, energy, efficiency, throughput and ease of use.

  13. High Resolution Robust GPS-free Localization for Wireless Sensor Networks and its Applications

    KAUST Repository

    Mirza, Mohammed

    2011-12-12

    In this thesis we investigate the problem of robustness and scalability w.r.t. estimating the position of randomly deployed motes/nodes of a Wireless Sensor Network (WSN) without the help of Global Positioning System (GPS) devices. We propose a few applications of range independent localization algorithms that allow the sensors to actively determine their location with high resolution without increasing the complexity of the hardware or any additional device setup. In our first application we try to present a localized and centralized cooperative spectrum sensing using RF sensor networks. This scheme collaboratively sense the spectrum and localize the whole network efficiently and with less difficulty. In second application we try to focus on how efficiently we can localize the nodes, to detect underwater threats, without the use of beacons. In third application we try to focus on 3-Dimensional localization for LTE systems. Our performance evaluation shows that these schemes lead to a significant improvement in localization accuracy compared to the state-of-art range independent localization schemes, without requiring GPS support.

  14. Community Air Sensor Network (CAIRSENSE) project: Evaluation of low-cost sensor performance in a suburban environment in the southeastern United States

    Science.gov (United States)

    Advances in air pollution sensor technology have enabled the development of small and low cost systems to measure outdoor air pollution. The deployment of a large number of sensors across a small geographic area would have potential benefits to supplement traditional monitoring n...

  15. Abstracting application deployment on Cloud infrastructures

    Science.gov (United States)

    Aiftimiei, D. C.; Fattibene, E.; Gargana, R.; Panella, M.; Salomoni, D.

    2017-10-01

    Deploying a complex application on a Cloud-based infrastructure can be a challenging task. In this contribution we present an approach for Cloud-based deployment of applications and its present or future implementation in the framework of several projects, such as “!CHAOS: a cloud of controls” [1], a project funded by MIUR (Italian Ministry of Research and Education) to create a Cloud-based deployment of a control system and data acquisition framework, “INDIGO-DataCloud” [2], an EC H2020 project targeting among other things high-level deployment of applications on hybrid Clouds, and “Open City Platform”[3], an Italian project aiming to provide open Cloud solutions for Italian Public Administrations. We considered to use an orchestration service to hide the complex deployment of the application components, and to build an abstraction layer on top of the orchestration one. Through Heat [4] orchestration service, we prototyped a dynamic, on-demand, scalable platform of software components, based on OpenStack infrastructures. On top of the orchestration service we developed a prototype of a web interface exploiting the Heat APIs. The user can start an instance of the application without having knowledge about the underlying Cloud infrastructure and services. Moreover, the platform instance can be customized by choosing parameters related to the application such as the size of a File System or the number of instances of a NoSQL DB cluster. As soon as the desired platform is running, the web interface offers the possibility to scale some infrastructure components. In this contribution we describe the solution design and implementation, based on the application requirements, the details of the development of both the Heat templates and of the web interface, together with possible exploitation strategies of this work in Cloud data centers.

  16. Distributed estimation of sensors position in underwater wireless sensor network

    Science.gov (United States)

    Zandi, Rahman; Kamarei, Mahmoud; Amiri, Hadi

    2016-05-01

    In this paper, a localisation method for determining the position of fixed sensor nodes in an underwater wireless sensor network (UWSN) is introduced. In this simple and range-free scheme, the node localisation is achieved by utilising an autonomous underwater vehicle (AUV) that transverses through the network deployment area, and that periodically emits a message block via four directional acoustic beams. A message block contains the actual known AUV position as well as a directional dependent marker that allows a node to identify the respective transmit beam. The beams form a fixed angle with the AUV body. If a node passively receives message blocks, it could calculate the arithmetic mean of the coordinates existing in each messages sequence, to find coordinates at two different time instants via two different successive beams. The node position can be derived from the two computed positions of the AUV. The major advantage of the proposed localisation algorithm is that it is silent, which leads to energy efficiency for sensor nodes. The proposed method does not require any synchronisation among the nodes owing to being silent. Simulation results, using MATLAB, demonstrated that the proposed method had better performance than other similar AUV-based localisation methods in terms of the rates of well-localised sensor nodes and positional root mean square error.

  17. Scalable Coverage Maintenance for Dense Wireless Sensor Networks

    Directory of Open Access Journals (Sweden)

    Jun Lu

    2007-06-01

    Full Text Available Owing to numerous potential applications, wireless sensor networks have been attracting significant research effort recently. The critical challenge that wireless sensor networks often face is to sustain long-term operation on limited battery energy. Coverage maintenance schemes can effectively prolong network lifetime by selecting and employing a subset of sensors in the network to provide sufficient sensing coverage over a target region. We envision future wireless sensor networks composed of a vast number of miniaturized sensors in exceedingly high density. Therefore, the key issue of coverage maintenance for future sensor networks is the scalability to sensor deployment density. In this paper, we propose a novel coverage maintenance scheme, scalable coverage maintenance (SCOM, which is scalable to sensor deployment density in terms of communication overhead (i.e., number of transmitted and received beacons and computational complexity (i.e., time and space complexity. In addition, SCOM achieves high energy efficiency and load balancing over different sensors. We have validated our claims through both analysis and simulations.

  18. An Anti-Electromagnetic Attack PUF Based on a Configurable Ring Oscillator for Wireless Sensor Networks.

    Science.gov (United States)

    Lu, Zhaojun; Li, Dongfang; Liu, Hailong; Gong, Mingyang; Liu, Zhenglin

    2017-09-15

    Wireless sensor networks (WSNs) are an emerging technology employed in some crucial applications. However, limited resources and physical exposure to attackers make security a challenging issue for a WSN. Ring oscillator-based physical unclonable function (RO PUF) is a potential option to protect the security of sensor nodes because it is able to generate random responses efficiently for a key extraction mechanism, which prevents the non-volatile memory from storing secret keys. In order to deploy RO PUF in a WSN, hardware efficiency, randomness, uniqueness, and reliability should be taken into account. Besides, the resistance to electromagnetic (EM) analysis attack is important to guarantee the security of RO PUF itself. In this paper, we propose a novel architecture of configurable RO PUF based on exclusive-or (XOR) gates. First, it dramatically increases the hardware efficiency compared with other types of RO PUFs. Second, it mitigates the vulnerability to EM analysis attack by placing the adjacent RO arrays in accordance with the cosine wave and sine wave so that the frequency of each RO cannot be detected. We implement our proposal in XINLINX A-7 field programmable gate arrays (FPGAs) and conduct a set of experiments to evaluate the quality of the responses. The results show that responses pass the National Institute of Standards and Technology (NIST) statistical test and have good uniqueness and reliability under different environments. Therefore, the proposed configurable RO PUF is suitable to establish a key extraction mechanism in a WSN.

  19. Subsurface material identification and sensor selection

    Science.gov (United States)

    T, H.; Reghunadh, R.; Ramesh, M. V.

    2017-12-01

    In India, most of the landslides occur during monsoon season and causes huge loss of life and property. Design of an early warning system for highly landslide prone area will reduce losses to a great extent. The in-situ monitoring systems needs deployment of several sensors inside a borehole for monitoring a particular slope. Amrita Center for Wireless Networks and Applications (AmritaWNA), Amrita University has designed, developed and deployed a Wireless Sensor Network (WSN) for real time landslide monitoring using geotechnical instruments and sensors like rain gauge, moisture sensor, piezometer, strain gauge, tilt meter and geophone inside a Deep Earth Probe (DEP) at different locations. These sensors provide point measurements of the subsurface at a higher accuracy. Every landslide prone terrain is unique with respect to its geology, hydrological conditions, meteorological conditions, velocity of movement etc. The decision of installing different geotechnical instruments in a landslide prone terrain is a crucial step to be considered. Rain gauge, moisture sensor, and piezometer are usually used in clay rich areas to sense the moisture and pore pressure values. Geophone and Crack meter are instruments used in rocky areas to monitor cracks and vibrations associated with a movement. Inclinometer and Strain gauge are usually placed inside a casing and can be used in both rocky and soil areas. In order to place geotechnical instruments and sensors at appropriate places Electrical Resistivity Tomography (ERT) method can be used. Variation in electrical resistivity values indicate the changes in composition, layer thickness, or contaminant levels. The derived true resistivity image can be used for identifying the type of materials present in the subsurface at different depths. We have used this method for identifying the type of materials present in our site at Chandmari (Sikkim). Fig 1 shows the typical resistivity values of a particular area in Chandmari site. The

  20. Radiation sensor

    International Nuclear Information System (INIS)

    Brown, W.L.; Geronime, R.L.

    1977-01-01

    Radiation sensor and thermocouple, respectively, which can be used for reactor in-core instrumentation. The radiation sensor consists of an inconel conductor wire and rhodium emitter wire, the thermocouple of two intertwined alumel or chromel wires. Both are arranged in the center of a metal tube relative to which they are separated by an insulator made of SiO 2 fibers. This insulator is first introduced as a loose fabric between the radiation sensor and the thermocouple, respectively, and the metal tube and then compacted to a density of 35-73% of pure SiO 2 by drawing the tube. There is no need for soldering or welding. The insulation resistivity at room temperature ist between 10 14 and 10 15 ohms. (ORU) [de

  1. Water Sensors

    Science.gov (United States)

    1992-01-01

    Mike Morris, former Associate Director of STAC, formed pHish Doctor, Inc. to develop and sell a pH monitor for home aquariums. The monitor, or pHish Doctor, consists of a sensor strip and color chart that continually measures pH levels in an aquarium. This is important because when the level gets too high, ammonia excreted by fish is highly toxic; at low pH, bacteria that normally break down waste products stop functioning. Sales have run into the tens of thousands of dollars. A NASA Tech Brief Technical Support Package later led to a salt water version of the system and a DoE Small Business Innovation Research (SBIR) grant for development of a sensor for sea buoys. The company, now known as Ocean Optics, Inc., is currently studying the effects of carbon dioxide buildup as well as exploring other commercial applications for the fiber optic sensor.

  2. Public Auditing with Privacy Protection in a Multi-User Model of Cloud-Assisted Body Sensor Networks

    Science.gov (United States)

    Li, Song; Cui, Jie; Zhong, Hong; Liu, Lu

    2017-01-01

    Wireless Body Sensor Networks (WBSNs) are gaining importance in the era of the Internet of Things (IoT). The modern medical system is a particular area where the WBSN techniques are being increasingly adopted for various fundamental operations. Despite such increasing deployments of WBSNs, issues such as the infancy in the size, capabilities and limited data processing capacities of the sensor devices restrain their adoption in resource-demanding applications. Though providing computing and storage supplements from cloud servers can potentially enrich the capabilities of the WBSNs devices, data security is one of the prevailing issues that affects the reliability of cloud-assisted services. Sensitive applications such as modern medical systems demand assurance of the privacy of the users’ medical records stored in distant cloud servers. Since it is economically impossible to set up private cloud servers for every client, auditing data security managed in the remote servers has necessarily become an integral requirement of WBSNs’ applications relying on public cloud servers. To this end, this paper proposes a novel certificateless public auditing scheme with integrated privacy protection. The multi-user model in our scheme supports groups of users to store and share data, thus exhibiting the potential for WBSNs’ deployments within community environments. Furthermore, our scheme enriches user experiences by offering public verifiability, forward security mechanisms and revocation of illegal group members. Experimental evaluations demonstrate the security effectiveness of our proposed scheme under the Random Oracle Model (ROM) by outperforming existing cloud-assisted WBSN models. PMID:28475110

  3. Public Auditing with Privacy Protection in a Multi-User Model of Cloud-Assisted Body Sensor Networks.

    Science.gov (United States)

    Li, Song; Cui, Jie; Zhong, Hong; Liu, Lu

    2017-05-05

    Wireless Body Sensor Networks (WBSNs) are gaining importance in the era of the Internet of Things (IoT). The modern medical system is a particular area where the WBSN techniques are being increasingly adopted for various fundamental operations. Despite such increasing deployments of WBSNs, issues such as the infancy in the size, capabilities and limited data processing capacities of the sensor devices restrain their adoption in resource-demanding applications. Though providing computing and storage supplements from cloud servers can potentially enrich the capabilities of the WBSNs devices, data security is one of the prevailing issues that affects the reliability of cloud-assisted services. Sensitive applications such as modern medical systems demand assurance of the privacy of the users' medical records stored in distant cloud servers. Since it is economically impossible to set up private cloud servers for every client, auditing data security managed in the remote servers has necessarily become an integral requirement of WBSNs' applications relying on public cloud servers. To this end, this paper proposes a novel certificateless public auditing scheme with integrated privacy protection. The multi-user model in our scheme supports groups of users to store and share data, thus exhibiting the potential for WBSNs' deployments within community environments. Furthermore, our scheme enriches user experiences by offering public verifiability, forward security mechanisms and revocation of illegal group members. Experimental evaluations demonstrate the security effectiveness of our proposed scheme under the Random Oracle Model (ROM) by outperforming existing cloud-assisted WBSN models.

  4. Functional Testing of Wireless Sensor Node Designs

    DEFF Research Database (Denmark)

    Virk, Kashif M.; Madsen, Jan

    2007-01-01

    Wireless sensor networks are networked embedded computer systems with stringent power, performance, cost and form-factor requirements along with numerous other constraints related to their pervasiveness and ubiquitousness. Therefore, only a systematic design methdology coupled with an efficient...... test approach can enable their conformance to design and deployment specifications. We discuss off-line, hierarchical, functional testing of complete wireless sensor nodes containing configurable logic through a combination of FPGA-based board test and Software-Based Self-Test (SBST) techniques...

  5. An End-to-End System to Enable Quick, Easy and Inexpensive Deployment of Hydrometeorological Stations

    Science.gov (United States)

    Celicourt, P.; Piasecki, M.

    2014-12-01

    The high cost of hydro-meteorological data acquisition, communication and publication systems along with limited qualified human resources is considered as the main reason why hydro-meteorological data collection remains a challenge especially in developing countries. Despite significant advances in sensor network technologies which gave birth to open hardware and software, low-cost (less than $50) and low-power (in the order of a few miliWatts) sensor platforms in the last two decades, sensors and sensor network deployment remains a labor-intensive, time consuming, cumbersome, and thus expensive task. These factors give rise for the need to develop a affordable, simple to deploy, scalable and self-organizing end-to-end (from sensor to publication) system suitable for deployment in such countries. The design of the envisioned system will consist of a few Sensed-And-Programmed Arduino-based sensor nodes with low-cost sensors measuring parameters relevant to hydrological processes and a Raspberry Pi micro-computer hosting the in-the-field back-end data management. This latter comprises the Python/Django model of the CUAHSI Observations Data Model (ODM) namely DjangODM backed by a PostgreSQL Database Server. We are also developing a Python-based data processing script which will be paired with the data autoloading capability of Django to populate the DjangODM database with the incoming data. To publish the data, the WOFpy (WaterOneFlow Web Services in Python) developed by the Texas Water Development Board for 'Water Data for Texas' which can produce WaterML web services from a variety of back-end database installations such as SQLite, MySQL, and PostgreSQL will be used. A step further would be the development of an appealing online visualization tool using Python statistics and analytics tools (Scipy, Numpy, Pandas) showing the spatial distribution of variables across an entire watershed as a time variant layer on top of a basemap.

  6. Randomization tests

    CERN Document Server

    Edgington, Eugene

    2007-01-01

    Statistical Tests That Do Not Require Random Sampling Randomization Tests Numerical Examples Randomization Tests and Nonrandom Samples The Prevalence of Nonrandom Samples in Experiments The Irrelevance of Random Samples for the Typical Experiment Generalizing from Nonrandom Samples Intelligibility Respect for the Validity of Randomization Tests Versatility Practicality Precursors of Randomization Tests Other Applications of Permutation Tests Questions and Exercises Notes References Randomized Experiments Unique Benefits of Experiments Experimentation without Mani

  7. Downhole Applications of Magnetic Sensors

    Directory of Open Access Journals (Sweden)

    Chinthaka P. Gooneratne

    2017-10-01

    Full Text Available In this paper we present a review of the application of two types of magnetic sensors—fluxgate magnetometers and nuclear magnetic resonance (NMR sensors—in the oil/gas industry. These magnetic sensors play a critical role in drilling wells safely, accurately and efficiently into a target reservoir zone by providing directional data of the well and acquiring information about the surrounding geological formations. Research into magnetic sensors for oil/gas drilling has not been explored by researchers to the same extent as other applications, such as biomedical, magnetic storage and automotive/aerospace applications. Therefore, this paper aims to serve as an opportunity for researchers to truly understand how magnetic sensors can be used in a downhole environment and to provide fertile ground for research and development in this area. A look ahead, discussing other magnetic sensor technologies that can potentially be used in the oil/gas industry is presented, and what is still needed in order deploy them in the field is also addressed.

  8. Garden State Parkway Corridor : ITS early deployment planning study : strategic deployment plan

    Science.gov (United States)

    1997-12-01

    This Strategic Deployment Plan describes ways of improving travel within the Garden : State Parkway Corridor using intelligent transportation systems (ITS) and without : constructing additional roadway lanes. Travel improvements will be possible with...

  9. Practical Use Technique of Sensor

    International Nuclear Information System (INIS)

    Hwang, Gyu Seop

    1985-11-01

    This book tells of practical use technology of sensor, introducing the recent trend of sensor for electronic industry, IC temperature sensor, radiation temperature sensor of surface acoustic wave, optical fiber temperature sensor, a polyelectrolyte film humidity sensor, semiconductor pressure sensor for industrial instrumentation, silicon integration pressure sensor, thick film humidity sensor and its application, photo sensor reflection type, and color sensor. It also deals with sensor for FA, sensor for a robot and sensor for the chemical industry.

  10. Practical Use Technique of Sensor

    Energy Technology Data Exchange (ETDEWEB)

    Hwang, Gyu Seop

    1985-11-15

    This book tells of practical use technology of sensor, introducing the recent trend of sensor for electronic industry, IC temperature sensor, radiation temperature sensor of surface acoustic wave, optical fiber temperature sensor, a polyelectrolyte film humidity sensor, semiconductor pressure sensor for industrial instrumentation, silicon integration pressure sensor, thick film humidity sensor and its application, photo sensor reflection type, and color sensor. It also deals with sensor for FA, sensor for a robot and sensor for the chemical industry.

  11. Next generation sensing platforms for extended deployments in large-scale, multidisciplinary, adaptive sampling and observational networks

    Science.gov (United States)

    Cross, J. N.; Meinig, C.; Mordy, C. W.; Lawrence-Slavas, N.; Cokelet, E. D.; Jenkins, R.; Tabisola, H. M.; Stabeno, P. J.

    2016-12-01

    New autonomous sensors have dramatically increased the resolution and accuracy of oceanographic data collection, enabling rapid sampling over extremely fine scales. Innovative new autonomous platofrms like floats, gliders, drones, and crawling moorings leverage the full potential of these new sensors by extending spatiotemporal reach across varied environments. During 2015 and 2016, The Innovative Technology for Arctic Exploration Program at the Pacific Marine Environmental Laboratory tested several new types of fully autonomous platforms with increased speed, durability, and power and payload capacity designed to deliver cutting-edge ecosystem assessment sensors to remote or inaccessible environments. The Expendable Ice-Tracking (EXIT) gloat developed by the NOAA Pacific Marine Environmental Laboratory (PMEL) is moored near bottom during the ice-free season and released on an autonomous timer beneath the ice during the following winter. The float collects a rapid profile during ascent, and continues to collect critical, poorly-accessible under-ice data until melt, when data is transmitted via satellite. The autonomous Oculus sub-surface glider developed by the University of Washington and PMEL has a large power and payload capacity and an enhanced buoyancy engine. This 'coastal truck' is designed for the rapid water column ascent required by optical imaging systems. The Saildrone is a solar and wind powered ocean unmanned surface vessel (USV) developed by Saildrone, Inc. in partnership with PMEL. This large-payload (200 lbs), fast (1-7 kts), durable (46 kts winds) platform was equipped with 15 sensors designed for ecosystem assessment during 2016, including passive and active acoustic systems specially redesigned for autonomous vehicle deployments. The senors deployed on these platforms achieved rigorous accuracy and precision standards. These innovative platforms provide new sampling capabilities and cost efficiencies in high-resolution sensor deployment

  12. Promoting parenting to support reintegrating military families: after deployment, adaptive parenting tools.

    Science.gov (United States)

    Gewirtz, Abigail H; Pinna, Keri L M; Hanson, Sheila K; Brockberg, Dustin

    2014-02-01

    The high operational tempo of the current conflicts and the unprecedented reliance on National Guard and Reserve forces highlights the need for services to promote reintegration efforts for those transitioning back to civilian family life. Despite evidence that parenting has significant influence on children's functioning, and that parenting may be impaired during stressful family transitions, there is a dearth of empirically supported psychological interventions tailored for military families reintegrating after deployment. This article reports on the modification of an empirically supported parenting intervention for families in which a parent has deployed to war. A theoretical rationale for addressing parenting during reintegration after deployment is discussed. We describe the intervention, After Deployment, Adaptive Parenting Tools (ADAPT), and report early feasibility and acceptability data from a randomized controlled effectiveness trial of ADAPT, a 14-week group-based, Web-enhanced parenting training program. Among the first 42 families assigned to the intervention group, participation rates were high, and equal among mothers and fathers. Satisfaction was high across all 14 sessions. Implications for psychological services to military families dealing with the deployment process are discussed. PsycINFO Database Record (c) 2014 APA, all rights reserved.

  13. Evaluation of a Multimedia Intervention for Children and Families Facing Multiple Military Deployments.

    Science.gov (United States)

    Flittner O'Grady, Allison; Thomaseo Burton, E; Chawla, Neelu; Topp, David; MacDermid Wadsworth, Shelley

    2016-02-01

    Repeated military deployments have been a common experience for many military families in the past 15 years. While there has been an increase in research and intervention focused on the effects on families of military deployments, much of this work has not focused specifically on the particular needs of young children. Talk, Listen, Connect: Multiple Deployments (TLC-II MD), a multimedia kit designed for home use, is among the first interventions directed toward young children. Created by Sesame Workshop and using popular Sesame Street characters, TLC-II MD was designed to support and equip families with young children with skills to address challenges associated with multiple deployments. This study utilized a randomized experimental design to evaluate the impact of TLC-II MD relative to a control condition using a Sesame Workshop multimedia kit not tailored to military families. Parents in both groups reported that children enjoyed the video overall and watched it repeatedly. Also in both groups, caregivers' depressive symptoms and children's aggressive behaviors declined significantly over time. Caregivers in the test group reported significantly larger increases in comfort discussing the deployment with their child and stronger perceptions that the DVD helped children to cope. Thus, the resilience-oriented materials were helpful to both groups, but those tailored to military families were significantly more likely to be perceived as helpful. Findings offer evidence regarding the ability of multimedia self-administered interventions to assist military families.

  14. Chemical sensor

    Science.gov (United States)

    Rauh, R. David (Inventor)

    1990-01-01

    A sensor for detecting a chemical substance includes an insertion element having a structure which enables insertion of the chemical substance with a resulting change in the bulk electrical characteristics of the insertion element under conditions sufficient to permit effective insertion; the change in the bulk electrical characteristics of the insertion element is detected as an indication of the presence of the chemical substance.

  15. Load sensor

    NARCIS (Netherlands)

    Van den Ende, D.; Almeida, P.M.R.; Dingemans, T.J.; Van der Zwaag, S.

    2007-01-01

    The invention relates to a load sensor comprising a polymer matrix and a piezo-ceramic material such as PZT, em not bedded in the polymer matrix, which together form a compos not ite, wherein the polymer matrix is a liquid crystalline resin, and wherein the piezo-ceramic material is a PZT powder

  16. Gas sensor

    Science.gov (United States)

    Schmid, Andreas K.; Mascaraque, Arantzazu; Santos, Benito; de la Figuera, Juan

    2014-09-09

    A gas sensor is described which incorporates a sensor stack comprising a first film layer of a ferromagnetic material, a spacer layer, and a second film layer of the ferromagnetic material. The first film layer is fabricated so that it exhibits a dependence of its magnetic anisotropy direction on the presence of a gas, That is, the orientation of the easy axis of magnetization will flip from out-of-plane to in-plane when the gas to be detected is present in sufficient concentration. By monitoring the change in resistance of the sensor stack when the orientation of the first layer's magnetization changes, and correlating that change with temperature one can determine both the identity and relative concentration of the detected gas. In one embodiment the stack sensor comprises a top ferromagnetic layer two mono layers thick of cobalt deposited upon a spacer layer of ruthenium, which in turn has a second layer of cobalt disposed on its other side, this second cobalt layer in contact with a programmable heater chip.

  17. Deployable reflector configurations. [for space telescope

    Science.gov (United States)

    Meinel, A. B.; Meinel, M. P.; Woolf, N. J.

    1983-01-01

    Both the theoretical reasons for considering a non-circular format for the Large Deployable Reflector, and a potentially realizable concept for such a device, are discussed. The optimum systems for diffraction limited telescopes with incoherent detection have either a single filled aperture, or two such apertures as an interferometer to synthesize a larger aperture. For a single aperture of limited area, a reflector in the form of a slot can be used to give increased angular resolution. It is shown how a 20 x 8 meter telescope can be configured to fit the Space Shuttle bay, and deployed with relatively simple operations. The relationship between the sunshield design and the inclination of the orbit is discussed. The possible use of the LDR as a basic module to permit the construction of supergiant space telescopes and interferometers both for IR/submm studies and for the entire ultraviolet through mm wave spectral region is discussed.

  18. Planning and Management of Technology Deployment Center

    International Nuclear Information System (INIS)

    Park, Jae Won; Joo, Po Kook; Kim, Jun Yeon and others

    2005-08-01

    The R and D contents are summarized as follows ; Models were set-up for transferring the developed technologies to the industry and managing technology deployment center to vitalize the commercialization and then the set-up model was tried to apply for transferring technologies for commercialization and to define interfaces between the R and D and industrial applications In this project, new products and processes were developed for promoting the commercialization. Infra-structures were firmly set-up for the venture company promotion and technology deployment developed during executing the proton Engineering frontier Project. Commercialization methodology connection with industrial companies were studied by outside specializing institute. Development of gem-stone coloring and new photo catalyst producing techniques are very high value-adding technologies, therefore, experimental and theoretical R and D were transacted simultaneously to obtain the originality of the technology. The theoretical R and D was committed to a specialist outside

  19. Effects of Wearable Sensor-Based Balance and Gait Training on Balance, Gait, and Functional Performance in Healthy and Patient Populations: A Systematic Review and Meta-Analysis of Randomized Controlled Trials.

    Science.gov (United States)

    Gordt, Katharina; Gerhardy, Thomas; Najafi, Bijan; Schwenk, Michael

    2018-01-01

    Wearable sensors (WS) can accurately measure body motion and provide interactive feedback for supporting motor learning. This review aims to summarize current evidence for the effectiveness of WS training for improving balance, gait and functional performance. A systematic literature search was performed in PubMed, Cochrane, Web of Science, and CINAHL. Randomized controlled trials (RCTs) using a WS exercise program were included. Study quality was examined by the PEDro scale. Meta-analyses were conducted to estimate the effects of WS balance training on the most frequently reported outcome parameters. Eight RCTs were included (Parkinson n = 2, stroke n = 1, Parkinson/stroke n = 1, peripheral neuropathy n = 2, frail older adults n = 1, healthy older adults n = 1). The sample size ranged from n = 20 to 40. Three types of training paradigms were used: (1) static steady-state balance training, (2) dynamic steady-state balance training, which includes gait training, and (3) proactive balance training. RCTs either used one type of training paradigm (type 2: n = 1, type 3: n = 3) or combined different types of training paradigms within their intervention (type 1 and 2: n = 2; all types: n = 2). The meta-analyses revealed significant overall effects of WS training on static steady-state balance outcomes including mediolateral (eyes open: Hedges' g = 0.82, CI: 0.43-1.21; eyes closed: g = 0.57, CI: 0.14-0.99) and anterior-posterior sway (eyes open: g = 0.55, CI: 0.01-1.10; eyes closed: g = 0.44, CI: 0.02-0.86). No effects on habitual gait speed were found in the meta-analysis (g = -0.19, CI: -0.68 to 0.29). Two RCTs reported significant improvements for selected gait variables including single support time, and fast gait speed. One study identified effects on proactive balance (Alternate Step Test), but no effects were found for the Timed Up and Go test and the Berg Balance Scale. Two studies reported positive results on feasibility and usability. Only one study was

  20. Towards the Ubiquitous Deployment of DNSSEC

    Science.gov (United States)

    2016-01-01

    and Session Initiation Protocol ( SIP ). However, it remains to be seen how quickly these enhancements are picked up and deployed. The second...Security RDI Resources for the DNSSEC Initiative System (the C&A system) RFC Request For Comments SIP Session Initiation Protocol SMTP Simple Mail...DISTRIBUTION UNLIMITED 1 Summary The Secure Extensions to the Domain Name System (DNSSEC) comprise of a set of protocol extensions that fix a

  1. THE PROTECTION AND DEPLOYMENT OF FINANCIAL INNOVATION

    OpenAIRE

    PETER GIANIODIS; JILL A. BROWN

    2013-01-01

    Prevailing theory suggests that firms that effectively protect technological discoveries from emulation will create and capture value. Despite its importance, little research has examined the specific mechanisms of how to protect technological discoveries, and have heretofore emphasized the importance of inherent resource attributes to limit competitor emulation. Using a sample of financial patents, we test theory regarding the effects of resource attributes and deployment mechanisms on resou...

  2. IRIS. Progress in licensing and toward deployment

    International Nuclear Information System (INIS)

    Petrovic, B.; Carelli, M.D.; Kling, C.L.; Cavlina, N.; Grgic, D.

    2006-01-01

    The International Reactor Innovative and Secure (IRIS) is an advanced, integral, light water cooled, pressurized reactor of smaller generating capacity (1000 MWt, or 335 MWe). It is being developed through a strong international partnership by a team lead by Westinghouse and including organizations from 10 countries. The main objective of the project is to offer a simple nuclear power plant with outstanding safety, attractive economics and enhanced proliferation resistance characteristics ready for deployment within the next decade. IRIS embodies the requirements set forth by the recently announced US DOE Global Nuclear Energy Partnership (GNEP) program for worldwide deployment of a smaller-scale reactors and provides a viable bridge to Generation IV reactors. IRIS is designed to address the needs of both developed and emerging markets. Its smaller power level provides deployment flexibility in larger developed markets, and makes it in particular well suited for markets with limited grids or where the annual energy demand growth is moderate. Due to its short construction time and the staggered build option, IRIS significantly reduces the required financing, improves cash flow, and provides a viable solution for economies with limited resources. While based on proven and worldwide accepted LWR technology, IRIS introduces a number of innovative solutions to simplify its design and improve safety and operational characteristics, including the integral primary system and its components, as well as the safety-by-design approach. These features will be tested and demonstrated in a testing program that has been initiated. As its centerpiece, the program will include the integral test facility. Results of this program will support licensing with the US NRC. A multinational licensing is considered to facilitate worldwide deployment. (author)

  3. Bomber Deployments: A New Power Projection Strategy

    Science.gov (United States)

    2016-08-21

    AIR COMMAND AND STAFF COLLEGE DISTANCE LEARNING AIR UNIVERSITY BOMBER DEPLOYMENTS: A NEW POWER PROJECTION STRATEGY by...operating base (FOB), main operating base ( MOB ) and intermediate staging base (ISB).10 Each type of base requires certain actions to make it suitable for...closure of many main operating bases ( MOB ) overseas and the reluctance of many nations to permit permanent military bases on their soil.”15 This

  4. Quality Function Deployment for Large Systems

    Science.gov (United States)

    Dean, Edwin B.

    1992-01-01

    Quality Function Deployment (QFD) is typically applied to small subsystems. This paper describes efforts to extend QFD to large scale systems. It links QFD to the system engineering process, the concurrent engineering process, the robust design process, and the costing process. The effect is to generate a tightly linked project management process of high dimensionality which flushes out issues early to provide a high quality, low cost, and, hence, competitive product. A pre-QFD matrix linking customers to customer desires is described.

  5. Robotic arm design for a remotely-deployed, in situ waste characterization probe

    International Nuclear Information System (INIS)

    Kress, R.L.; Jansen, J.F.; Haas, J.W.

    1991-01-01

    This paper describes some design considerations for a system which will combine robotics and laser spectroscopy to produce an in situ monitoring system for heterogeneous waste materials. The new system will provide faster, cheaper, safer, and more complete characterization of mixed solids and liquids stored in tanks and drums or buried in pits. A small, fiberoptic multiprobe that performs Raman and fluorescence measurements of wastes composed of a variety of organic and inorganic compounds will be described. Design considerations for a novel sensor platform that positions and stabilizes the multiprobe relative to the sampling point in order to make accurate spectroscopic measurements and deploys the sensor in hazardous environments with minimal risk to workers will be presented. The core of the platform will be a 3-Degrees-Of-Freedom (3-DOF), spherical coordinate end effector equipped with a proximity sensor that compensates for errors introduced by the flexible nature of the support arm. The platform can be adapted to operate the most robotic deployment systems used in hazardous environments. The multisensor probe will be coupled to remote, portable laser spectrometer systems by a fiber-optic bundle. 5 refs

  6. Robotic arm design for a remotely-deployed, in situ waste characterization probe

    International Nuclear Information System (INIS)

    Kress, Reid; Haas, John; Jansen, John

    1992-01-01

    This paper describes some design considerations for a system which will combine robotics and laser spectroscopy to produce an in situ monitoring system for heterogeneous waste materials. The new system will provide faster, cheaper) safer, and more complete characterization of mixed solids and liquids stored in tanks and drums or buried in pits. A small, fiberoptic multiprobe that performs Raman and fluorescence measurements of wastes composed of a variety of organic and inorganic compounds will be described. Design considerations for a novel sensor platform that positions and stabilizes the multiprobe relative to the sampling point in order to male accurate spectroscopic measurements and deploys the sensor in hazardous environments with minimal risk to workers will be presented. The core of (he platform will be a 3-Degrees-Of-Freedom (3-DOF), spherical coordinate end effector equipped with a proximity sensor that compensates for errors introduced by the flexible nature of the support arm. The platform can be adapted to operate with most robotic deployment systems used in hazardous environments. The multisensor probe will be coupled to remote, portable laser spectrometer systems by a fiber-optic bundle. (author)

  7. Reactor power system deployment and startup

    International Nuclear Information System (INIS)

    Wetch, J.R.; Nelin, C.J.; Britt, E.J.; Klein, G.; Rasor Associates, Inc., Sunnyvale, CA; California Institute of Technology, Pasadena)

    1985-01-01

    This paper addresses issues that should receive further examination in the near-term as concept selection for development of a U.S. space reactor power system is approached. The issues include: the economics, practicality and system reliability associated with transfer of nuclear spacecraft from low earth shuttle orbits to operational orbits, via chemical propulsion versus nuclear electric propulsion; possible astronaut supervised reactor and nuclear electric propulsion startup in low altitude Shuttle orbit; potential deployment methods for nuclear powered spacecraft from Shuttle; the general public safety of low altitude startup and nuclear safe and disposal orbits; the question of preferred reactor power level; and the question of frozen versus molten alkali metal coolant during launch and deployment. These issues must be considered now because they impact the SP-100 concept selection, power level selection, weight and size limits, use of deployable radiators, reliability requirements, and economics, as well as the degree of need for and the urgency of developing space reactor power systems. 5 references

  8. FBR/VHTR deployment scenarios in Japan

    International Nuclear Information System (INIS)

    Richards, Matt; Kunitomi, Kazuhiko

    2008-01-01

    Co-deployment of Fast Breeder Reactors (FBRs) and Very High Temperature Reactors (VHTRs) can be used as the nuclear technologies to meet a significant portion of Japan's future energy demands. The FBR provides the fissile fuel for energy security and sustainability, and can be used to provide a significant portion of the electricity demand. The VHTR can provide flexible energy outputs (electricity, hydrogen, and high-temperature heat) with high efficiency, can operate with a wide variety of fuel cycles, and can be sited at locations that have limited availability of cooling water. These features, combined with its passive safety and high degree of proliferation resistance, make the VHTR an ideal complement for co-deployment with the FBR in Japan and also a very low-risk technology of export to foreign countries. In addition to hydrogen production, the high-temperature thermal energy produced by the VHTR fleet can be used for a wide variety of process-heat applications, and the VHTR can play a key role for significantly reducing greenhouse-gas emissions. This paper describes assessments for deploying FBRs and VHTRs in Japan using a closed fuel cycle, with the FBRs supplying the fissile material to sustain the combined FBR/VHTR fleet. (author)

  9. Hybrid deployable support truss designs for LDR

    Science.gov (United States)

    Hedgepeth, J.

    1988-01-01

    Concepts for a 20-meter diameter Large Deployable Reflector (LDR) deployable truss backup structure, and analytical predictions of its structural characteristics are discussed. The concept shown is referred to as the SIXPAC; It is a combination of the PACTRUSS concept and a single-fold beam, which would make up the desired backup structure. One advantage of retaining the PACTRUSS concept is its packaging density and its capability for synchronous deployment. Various 2-meter hexagonal panel arrangements are possible for this Hybrid PACTRUSS structure depending on the panel-to-structure attachment strategies used. Static analyses of the SIXPAC using various assumptions for truss designs and panel masses of 10 kg sq meters were performed to predict the tip displacement of the structure when supported at the center. The tip displacement ranged from 0.20 to 0.44 mm without the panel mass, and from 0.9 to 3.9 mm with the panel mass (in a 1-g field). The data indicate that the structure can be adequately ground tested to validate its required performance in space, assuming the required performance in space is approximately 100 microns. The static displacement at the tip of the structure when subjected to an angular acceleration of 0.001 rad/sec squared were estimated to range from 0.8 to 7.5 microns, depending on the type of truss elements.

  10. A Mobile Sensor Network System for Monitoring of Unfriendly Environments.

    Science.gov (United States)

    Song, Guangming; Zhou, Yaoxin; Ding, Fei; Song, Aiguo

    2008-11-14

    Observing microclimate changes is one of the most popular applications of wireless sensor networks. However, some target environments are often too dangerous or inaccessible to humans or large robots and there are many challenges for deploying and maintaining wireless sensor networks in those unfriendly environments. This paper presents a mobile sensor network system for solving this problem. The system architecture, the mobile node design, the basic behaviors and advanced network capabilities have been investigated respectively. A wheel-based robotic node architecture is proposed here that can add controlled mobility to wireless sensor networks. A testbed including some prototype nodes has also been created for validating the basic functions of the proposed mobile sensor network system. Motion performance tests have been done to get the positioning errors and power consumption model of the mobile nodes. Results of the autonomous deployment experiment show that the mobile nodes can be distributed evenly into the previously unknown environments. It provides powerful support for network deployment and maintenance and can ensure that the sensor network will work properly in unfriendly environments.

  11. Results from bonding of the SALT primary mirror edge sensors

    Science.gov (United States)

    Strydom, Ockert J.; Love, Jonathan; Gajjar, Hitesh

    2016-07-01

    The Southern African Large Telescope has till recently operated without active closed loop control of its Primary Mirror. The reason for this was that there were no suitable edge sensor system available on the market. Recently a system became available and SALT form Fogale Nanotech. The system consist of a sensor, cables and control electronics. The system was still under development and SALT was responsible for the integration of the sensors before deployment on the Telescope. Several issues still had to be addressed. One of these issues was the integration of the sensors at an appropriate production rate. The sensors was supplied as flexible pc boards with different types making up the transmitters and receivers. These flexible boards were bonded to ClearCeram Z L-Brackets before the appropriate connectors were installed. This paper describes the process used to integrate and test the sensors.

  12. Associations of contextual risk and protective factors with fathers’ parenting practices in the post-deployment environment

    Science.gov (United States)

    Davis, Laurel; Hanson, Sheila K.; Zamir, Osnat; Gewirtz, Abigail H.; DeGarmo, David S.

    2015-01-01

    Deployment separation and reunifications are salient contexts that directly impact effective family functioning and parenting for military fathers. Yet, we know very little about determinants of post-deployed father involvement and effective parenting. The present study examined hypothesized risk and protective factors of observed parenting for 282 post-deployed fathers who served in the Army National Guard/Reserves. Pre-intervention data were employed from fathers participating in the After Deployment, Adaptive Parenting Tools (ADAPT) randomized control trial. Parenting practices were obtained from direct observation of father-child interaction and included measures of problem solving, harsh discipline, positive involvement, encouragement, and monitoring. Risk factors included combat exposure, negative life events, months deployed, and PTSD symptoms. Protective factors included education, income, dyadic adjustment, and social support. Results of a structural equation model predicting an effective parenting construct indicated that months deployed, income, and father age were most related to observed parenting, explaining 16% of the variance. We are aware of no other study utilizing direct parent-child observations of father’s parenting skills following overseas deployment. Implications for practice and preventive intervention are discussed. PMID:26213794

  13. Coverage Improvement for Wireless Sensor Networks using Grid Quorum based Node Mobility

    DEFF Research Database (Denmark)

    Mathur, Prateek; Nielsen, Rasmus Hjorth; Prasad, Neeli R.

    2012-01-01

    Coverage of wireless sensor networks (WSNs) is an important quality of service (QoS) metric and often the desired coverage is not attainable at the initial deployment, but node mobility can be used to improve the coverage by relocating sensor nodes. Unconstrained node mobility is considered infea...

  14. Teaching the Geoweb: Interdisciplinary Undergraduate Research in Wireless Sensor Networks, Web Mapping, and Geospatial Data Management

    Science.gov (United States)

    Abernathy, David

    2011-01-01

    This article addresses an effort to incorporate wireless sensor networks and the emerging tools of the Geoweb into undergraduate teaching and research at a small liberal arts college. The primary goal of the research was to identify the hardware, software, and skill sets needed to deploy a local sensor network, collect data, and transmit that data…

  15. A Machine Learning Approach for Identifying and Classifying Faults in Wireless Sensor Networks

    NARCIS (Netherlands)

    Warriach, Ehsan Ullah; Aiello, Marco; Tei, Kenji

    2012-01-01

    Wireless Sensor Network (WSN) deployment experiences show that collected data is prone to be faulty. Faults are due to internal and external influences, such as calibration, low battery, environmental interference and sensor aging. However, only few solutions exist to deal with faulty sensory data

  16. Reactive and adaptive monitoring to secure aggregation in wireless sensor networks

    NARCIS (Netherlands)

    Labraoui, Nabila; Gueroui, Mourad; Aliouat, Makhlouf; Petit, Jonathan

    Data aggregation is considered as one of the fundamental distributed data processing procedures for saving the energy and minimizing the medium access layer contention in wireless sensor networks. However, sensor networks are likely to be deployed in an untrusted environment, which make them

  17. System analysis and energy model for radio-triggered battery-less monolithic wireless sensor receiver

    NARCIS (Netherlands)

    Gao, H.; Wu, Y.; Matters - Kammerer, M.; Roermund, van Arthur; Baltus, P.G.M.

    2013-01-01

    Monolithic wireless sensors with integrated antenna, on-chip transceiving, sensing and energy scavenging are low-cost and robust, thus very suitable for mass production and deployment. The design of such a sensor node requires a proper architecture with careful trade-offs and joint considerations

  18. Modular VO oriented Java EE service deployer

    Science.gov (United States)

    Molinaro, Marco; Cepparo, Francesco; De Marco, Marco; Knapic, Cristina; Apollo, Pietro; Smareglia, Riccardo

    2014-07-01

    The International Virtual Observatory Alliance (IVOA) has produced many standards and recommendations whose aim is to generate an architecture that starts from astrophysical resources, in a general sense, and ends up in deployed consumable services (that are themselves astrophysical resources). Focusing on the Data Access Layer (DAL) system architecture, that these standards define, in the last years a web based application has been developed and maintained at INAF-OATs IA2 (Italian National institute for Astrophysics - Astronomical Observatory of Trieste, Italian center of Astronomical Archives) to try to deploy and manage multiple VO (Virtual Observatory) services in a uniform way: VO-Dance. However a set of criticalities have arisen since when the VO-Dance idea has been produced, plus some major changes underwent and are undergoing at the IVOA DAL layer (and related standards): this urged IA2 to identify a new solution for its own service layer. Keeping on the basic ideas from VO-Dance (simple service configuration, service instantiation at call time and modularity) while switching to different software technologies (e.g. dismissing Java Reflection in favour of Enterprise Java Bean, EJB, based solution), the new solution has been sketched out and tested for feasibility. Here we present the results originating from this test study. The main constraints for this new project come from various fields. A better homogenized solution rising from IVOA DAL standards: for example the new DALI (Data Access Layer Interface) specification that acts as a common interface system for previous and oncoming access protocols. The need for a modular system where each component is based upon a single VO specification allowing services to rely on common capabilities instead of homogenizing them inside service components directly. The search for a scalable system that takes advantage from distributed systems. The constraints find answer in the adopted solutions hereafter sketched. The

  19. Deployment of check-in nodes in complex networks

    Science.gov (United States)

    Jiang, Zhong-Yuan; Ma, Jian-Feng

    2017-01-01

    In many real complex networks such as the city road networks and highway networks, vehicles often have to pass through some specially functioned nodes to receive check-in like services such as gas supplement at gas stations. Based on existing network structures, to guarantee every shortest path including at least a check-in node, the location selection of all check-in nodes is very essential and important to make vehicles to easily visit these check-in nodes, and it is still remains an open problem in complex network studies. In this work, we aim to find possible solutions for this problem. We first convert it into a set cover problem which is NP-complete and propose to employ the greedy algorithm to achieve an approximate result. Inspired by heuristic information of network structure, we discuss other four check-in node location deployment methods including high betweenness first (HBF), high degree first (HDF), random and low degree first (LDF). Finally, we compose extensive simulations in classical scale-free networks, random networks and real network models, and the results can well confirm the effectiveness of the greedy algorithm. This work has potential applications into many real networks.

  20. Sparse Detector Imaging Sensor with Two-Class Silhouette Classification

    Directory of Open Access Journals (Sweden)

    David Russomanno

    2008-12-01

    Full Text Available This paper presents the design and test of a simple active near-infrared sparse detector imaging sensor. The prototype of the sensor is novel in that it can capture remarkable silhouettes or profiles of a wide-variety of moving objects, including humans, animals, and vehicles using a sparse detector array comprised of only sixteen sensing elements deployed in a vertical configuration. The prototype sensor was built to collect silhouettes for a variety of objects and to evaluate several algorithms for classifying the data obtained from the sensor into two classes: human versus non-human. Initial tests show that the classification of individually sensed objects into two classes can be achieved with accuracy greater than ninety-nine percent (99% with a subset of the sixteen detectors using a representative dataset consisting of 512 signatures. The prototype also includes a Webservice interface such that the sensor can be tasked in a network-centric environment. The sensor appears to be a low-cost alternative to traditional, high-resolution focal plane array imaging sensors for some applications. After a power optimization study, appropriate packaging, and testing with more extensive datasets, the sensor may be a good candidate for deployment in vast geographic regions for a myriad of intelligent electronic fence and persistent surveillance applications, including perimeter security scenarios.

  1. Development of an Open Source, Air-Deployable Weather Station

    Science.gov (United States)

    Krejci, A.; Lopez Alcala, J. M.; Nelke, M.; Wagner, J.; Udell, C.; Higgins, C. W.; Selker, J. S.

    2017-12-01

    We created a packaged weather station intended to be deployed in the air on tethered systems. The device incorporates lightweight sensors and parts and runs for up to 24 hours off of lithium polymer batteries, allowing the entire package to be supported by a thin fiber. As the fiber does not provide a stable platform, additional data (pitch and roll) from typical weather parameters (e.g. temperature, pressure, humidity, wind speed, and wind direction) are determined using an embedded inertial motion unit. All designs are open sourced including electronics, CAD drawings, and descriptions of assembly and can be found on the OPEnS lab website at http://www.open-sensing.org/lowcost-weather-station/. The Openly Published Environmental Sensing Lab (OPEnS: Open-Sensing.org) expands the possibilities of scientific observation of our Earth, transforming the technology, methods, and culture by combining open-source development and cutting-edge technology. New OPEnS labs are now being established in India, France, Switzerland, the Netherlands, and Ghana.

  2. Mechanical deployment system on aries an autonomous mobile robot

    International Nuclear Information System (INIS)

    Rocheleau, D.N.

    1995-01-01

    ARIES (Autonomous Robotic Inspection Experimental System) is under development for the Department of Energy (DOE) to survey and inspect drums containing low-level radioactive waste stored in warehouses at DOE facilities. This paper focuses on the mechanical deployment system-referred to as the camera positioning system (CPS)-used in the project. The CPS is used for positioning four identical but separate camera packages consisting of vision cameras and other required sensors such as bar-code readers and light stripe projectors. The CPS is attached to the top of a mobile robot and consists of two mechanisms. The first is a lift mechanism composed of 5 interlocking rail-elements which starts from a retracted position and extends upward to simultaneously position 3 separate camera packages to inspect the top three drums of a column of four drums. The second is a parallelogram special case Grashof four-bar mechanism which is used for positioning a camera package on drums on the floor. Both mechanisms are the subject of this paper, where the lift mechanism is discussed in detail

  3. Deployment Effects of Marin Renewable Energy Technologies

    Energy Technology Data Exchange (ETDEWEB)

    Brian Polagye; Mirko Previsic

    2010-06-17

    Given proper care in siting, design, deployment, operation and maintenance, marine and hydrokinetic technologies could become one of the more environmentally benign sources of electricity generation. In order to accelerate the adoption of these emerging hydrokinetic and marine energy technologies, navigational and environmental concerns must be identified and addressed. All developing hydrokinetic projects involve a wide variety of stakeholders. One of the key issues that site developers face as they engage with this range of stakeholders is that many of the possible conflicts (e.g., shipping and fishing) and environmental issues are not well-understood, due to a lack of technical certainty. In September 2008, re vision consulting, LLC was selected by the Department of Energy (DoE) to apply a scenario-based approach to the emerging wave and tidal technology sectors in order to evaluate the impact of these technologies on the marine environment and potentially conflicting uses. The project’s scope of work includes the establishment of baseline scenarios for wave and tidal power conversion at potential future deployment sites. The scenarios will capture variations in technical approaches and deployment scales to properly identify and characterize environmental impacts and navigational effects. The goal of the project is to provide all stakeholders with an improved understanding of the potential effects of these emerging technologies and focus all stakeholders onto the critical issues that need to be addressed. This groundwork will also help in streamlining siting and associated permitting processes, which are considered key hurdles for the industry’s development in the U.S. today. Re vision is coordinating its efforts with two other project teams funded by DoE which are focused on regulatory and navigational issues. The results of this study are structured into three reports: 1. Wave power scenario description 2. Tidal power scenario description 3. Framework for

  4. Fundamentals of 3D Deployable Mechanisms in Space

    Data.gov (United States)

    National Aeronautics and Space Administration — Fundamentals of 3D Deployable Origami Structures in Space The primary objectives of my research are to study the application of 3D deployable origami structures in...

  5. STEP flight experiments Large Deployable Reflector (LDR) telescope

    Science.gov (United States)

    Runge, F. C.

    1984-01-01

    Flight testing plans for a large deployable infrared reflector telescope to be tested on a space platform are discussed. Subsystem parts, subassemblies, and whole assemblies are discussed. Assurance of operational deployability, rigidization, alignment, and serviceability will be sought.

  6. Elastic Deployable Composite Tubular Roll-Out Boom, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — Deployable Space Systems (DSS) has developed an affordable and ultra-lightweight elastically self-deployable Roll-Out Boom technology that provides affordability and...

  7. A Conceptual Design for a Small Deployer Satellite

    Science.gov (United States)

    Zumbo, S.

    2002-01-01

    industrial partners, has started the development of a space mission, named DeSat, focused on a new highly innovative micro satellite bus for LEO, entirely designed by an integrated team of students and researchers. The first mission is scheduled to fly at the end of 2003 on a converted Russian ICBM. The paper is intended to present the main features of DeSat mission, its goals and the activities that have been done by students and researchers to achieve the micro satellite platform design. The principal payload of the entire system is represented by a recirculating ball screw boom whose mass reaches one third of the total mass budget. The goal of the mission is to demonstrate the validity of its design also for space applications, which may range from precise off platform positioning of devices and instruments to GPS interferometry, sensor measurements and robotics. The satellite geometry, when the boom is in deployed configuration, is so stretched that the name "deployable satellite" has come out naturally. The large deployment mechanism, compared to the small bus, has influenced the design of every satellite subsystem leading to innovative solutions in terms of design, materials, equipment and instruments.

  8. Competitive Swarm Optimizer Based Gateway Deployment Algorithm in Cyber-Physical Systems

    Directory of Open Access Journals (Sweden)

    Shuqiang Huang

    2017-01-01

    Full Text Available Wireless sensor network topology optimization is a highly important issue, and topology control through node selection can improve the efficiency of data forwarding, while saving energy and prolonging lifetime of the network. To address the problem of connecting a wireless sensor network to the Internet in cyber-physical systems, here we propose a geometric gateway deployment based on a competitive swarm optimizer algorithm. The particle swarm optimization (PSO algorithm has a continuous search feature in the solution space, which makes it suitable for finding the geometric center of gateway deployment; however, its search mechanism is limited to the individual optimum (pbest and the population optimum (gbest; thus, it easily falls into local optima. In order to improve the particle search mechanism and enhance the search efficiency of the algorithm, we introduce a new competitive swarm optimizer (CSO algorithm. The CSO search algorithm is based on an inter-particle competition mechanism and can effectively avoid trapping of the population falling into a local optimum. With the improvement of an adaptive opposition-based search and its ability to dynamically parameter adjustments, this algorithm can maintain the diversity of the entire swarm to solve geometric K-center gateway deployment problems. The simulation results show that this CSO algorithm has a good global explorative ability as well as convergence speed and can improve the network quality of service (QoS level of cyber-physical systems by obtaining a minimum network coverage radius. We also find that the CSO algorithm is more stable, robust and effective in solving the problem of geometric gateway deployment as compared to the PSO or Kmedoids algorithms.

  9. Competitive Swarm Optimizer Based Gateway Deployment Algorithm in Cyber-Physical Systems.

    Science.gov (United States)

    Huang, Shuqiang; Tao, Ming

    2017-01-22

    Wireless sensor network topology optimization is a highly important issue, and topology control through node selection can improve the efficiency of data forwarding, while saving energy and prolonging lifetime of the network. To address the problem of connecting a wireless sensor network to the Internet in cyber-physical systems, here we propose a geometric gateway deployment based on a competitive swarm optimizer algorithm. The particle swarm optimization (PSO) algorithm has a continuous search feature in the solution space, which makes it suitable for finding the geometric center of gateway deployment; however, its search mechanism is limited to the individual optimum (pbest) and the population optimum (gbest); thus, it easily falls into local optima. In order to improve the particle search mechanism and enhance the search efficiency of the algorithm, we introduce a new competitive swarm optimizer (CSO) algorithm. The CSO search algorithm is based on an inter-particle competition mechanism and can effectively avoid trapping of the population falling into a local optimum. With the improvement of an adaptive opposition-based search and its ability to dynamically parameter adjustments, this algorithm can maintain the diversity of the entire swarm to solve geometric K -center gateway deployment problems. The simulation results show that this CSO algorithm has a good global explorative ability as well as convergence speed and can improve the network quality of service (QoS) level of cyber-physical systems by obtaining a minimum network coverage radius. We also find that the CSO algorithm is more stable, robust and effective in solving the problem of geometric gateway deployment as compared to the PSO or Kmedoids algorithms.

  10. Competitive Swarm Optimizer Based Gateway Deployment Algorithm in Cyber-Physical Systems

    Science.gov (United States)

    Huang, Shuqiang; Tao, Ming

    2017-01-01

    Wireless sensor network topology optimization is a highly important issue, and topology control through node selection can improve the efficiency of data forwarding, while saving energy and prolonging lifetime of the network. To address the problem of connecting a wireless sensor network to the Internet in cyber-physical systems, here we propose a geometric gateway deployment based on a competitive swarm optimizer algorithm. The particle swarm optimization (PSO) algorithm has a continuous search feature in the solution space, which makes it suitable for finding the geometric center of gateway deployment; however, its search mechanism is limited to the individual optimum (pbest) and the population optimum (gbest); thus, it easily falls into local optima. In order to improve the particle search mechanism and enhance the search efficiency of the algorithm, we introduce a new competitive swarm optimizer (CSO) algorithm. The CSO search algorithm is based on an inter-particle competition mechanism and can effectively avoid trapping of the population falling into a local optimum. With the improvement of an adaptive opposition-based search and its ability to dynamically parameter adjustments, this algorithm can maintain the diversity of the entire swarm to solve geometric K-center gateway deployment problems. The simulation results show that this CSO algorithm has a good global explorative ability as well as convergence speed and can improve the network quality of service (QoS) level of cyber-physical systems by obtaining a minimum network coverage radius. We also find that the CSO algorithm is more stable, robust and effective in solving the problem of geometric gateway deployment as compared to the PSO or Kmedoids algorithms. PMID:28117735

  11. Characterization of Industrial Coolant Fluids and Continuous Ageing Monitoring by Wireless Node-Enabled Fiber Optic Sensors

    DEFF Research Database (Denmark)

    Sachat, Alexandros El; Meristoudi, Anastasia; Markos, Christos

    2017-01-01

    Environmentally robust chemical sensors for monitoring industrial processes or infrastructures are lately becoming important devices in industry. Low complexity and wireless enabled characteristics can offer the required flexibility for sensor deployment in adaptable sensing networks for continuous...... of sensors allowed their integration in an autonomous wireless sensing node, thus enabling the future use of the demonstrated platform in wireless sensor networks for a variety of industrial and environmental monitoring applications....

  12. Psychiatric Effects of Military Deployment on Children and Families

    Science.gov (United States)

    James, Trenton

    2012-01-01

    Deployments in the United States military have increased greatly in the past 10 years. Families and children are psychiatrically affected by these deployments, and recent studies are clarifying these effects. This article focuses on the psychiatric effects of deployment on children and uses a composite case example to review the use of play therapy to treat children who are having psychiatric issues related to the deployment of one or both parents. PMID:22468239

  13. Deployment-related risk factors of low back pain

    DEFF Research Database (Denmark)

    Nissen, Lars Ravnborg; Marott, Jacob Louis; Gyntelberg, Finn

    2014-01-01

    Where much is known about the consequences of spinal and low back pain (LBP) during military deployments, there is lesser knowledge of risk factors for LBP among the deployed forces. The objective of this study was to identify deployment-related exposures associated with LBP. The study was a ques...... their subordinates and involve medical personnel, especially deployed physiotherapists, by giving advice to soldiers of different military occupational specialties on how to optimize ergonomics at work....

  14. Design aspects of a deployable tensegrity-hollow-rope footbridge

    OpenAIRE

    Rhode-Barbarigos , Landolf; Bel Hadj Ali , Nizar; Motro , René; Smith , Ian F.C.

    2012-01-01

    International audience; Tensegrity structures are composed of cables and struts in a pre-stressed self-equilibrium. Although tensegrity first appeared in the 1950s, it is seldom used in civil engineering. This paper focuses on the design aspects of a deployable tensegrity-hollow-rope footbridge. Deployment is usually not a critical design case for traditional deployable structures. However, for tensegrity systems deployment may be critical due to the actuation required. In this paper, deploym...

  15. Semiconductor sensors

    International Nuclear Information System (INIS)

    Hartmann, Frank

    2011-01-01

    Semiconductor sensors have been around since the 1950s and today, every high energy physics experiment has one in its repertoire. In Lepton as well as Hadron colliders, silicon vertex and tracking detectors led to the most amazing physics and will continue doing so in the future. This contribution tries to depict the history of these devices exemplarily without being able to honor all important developments and installations. The current understanding of radiation damage mechanisms and recent R and D topics demonstrating the future challenges and possible technical solutions for the SLHC detectors are presented. Consequently semiconductor sensor candidates for an LHC upgrade and a future linear collider are also briefly introduced. The work presented here is a collage of the work of many individual silicon experts spread over several collaborations across the world.

  16. Load sensor

    OpenAIRE

    Van den Ende, D.; Almeida, P.M.R.; Dingemans, T.J.; Van der Zwaag, S.

    2007-01-01

    The invention relates to a load sensor comprising a polymer matrix and a piezo-ceramic material such as PZT, em not bedded in the polymer matrix, which together form a compos not ite, wherein the polymer matrix is a liquid crystalline resin, and wherein the piezo-ceramic material is a PZT powder forming 30-60% by volume of the composite, and wherein the PZT powder forms 40-50% by volume of the composite.

  17. Image Sensor

    OpenAIRE

    Jerram, Paul; Stefanov, Konstantin

    2017-01-01

    An image sensor of the type for providing charge multiplication by impact ionisation has plurality of multiplication elements. Each element is arranged to receive charge from photosensitive elements of an image area and each element comprises a sequence of electrodes to move charge along a transport path. Each of the electrodes has an edge defining a boundary with a first electrode, a maximum width across the charge transport path and a leading edge that defines a boundary with a second elect...

  18. Optischer Sensor

    OpenAIRE

    Brandenburg, A.; Fischer, A.

    1995-01-01

    An optical sensor (1) comprising an integrated optical arrangement has a waveguide (4) and at least one defraction grating (5) arranged in this waveguide. Light can launched into the waveguide via the defraction grating. In the reflection area of defraction grating, part of the light is dispersed through the waveguide at the beam angle for which the launch conditions and thus the defraction in the waveguide are fulfilled, so that, at this angle, a dark line (14) occurs whose position is evalu...

  19. Gas sensor

    International Nuclear Information System (INIS)

    Dorogan, V.; Korotchenkov, Gh.; Vieru, T.; Prodan, I.

    2003-01-01

    The invention relates to the gas sensors on base of metal-oxide films (SnO, InO), which may be used for enviromental control, in the fireextinguishing systema etc. The gas includes an insulating substrate, an active layer, a resistive layer with ohmic contacts. The resistive layer has two or more regions with dofferent resistances , and on the active layer are two or more pairs of ohmic contacts

  20. Experiences and recommendations in deploying a real-time, water quality monitoring system

    Science.gov (United States)

    O'Flynn, B.; Regan, F.; Lawlor, A.; Wallace, J.; Torres, J.; O'Mathuna, C.

    2010-12-01

    Monitoring of water quality at a river basin level to meet the requirements of the Water Framework Directive (WFD) using conventional sampling and laboratory-based techniques poses a significant financial burden. Wireless sensing systems offer the potential to reduce these costs considerably, as well as provide more useful, continuous monitoring capabilities by giving an accurate idea of the changing environmental and water quality in real time. It is unlikely that the traditional spot/grab sampling will provide a reasonable estimate of the true maximum and/or mean concentration for a particular physicochemical variable in a water body with marked temporal variability. When persistent fluctuations occur, it is likely only to be detected through continuous measurements, which have the capability of detecting sporadic peaks of concentration. Thus, in situ sensors capable of continuous sampling of parameters required under the WFD would therefore provide more up-to-date information, cut monitoring costs and provide better coverage representing long-term trends in fluctuations of pollutant concentrations. DEPLOY is a technology demonstration project, which began planning and station selection and design in August 2008 aiming to show how state-of-the-art technology could be implemented for cost-effective, continuous and real-time monitoring of a river catchment. The DEPLOY project is seen as an important building block in the realization of a wide area autonomous network of sensors capable of monitoring the spatial and temporal distribution of important water quality and environmental target parameters. The demonstration sites chosen are based in the River Lee, which flows through Ireland's second largest city, Cork, and were designed to include monitoring stations in five zones considered typical of significant river systems--these monitor water quality parameters such as pH, temperature, depth, conductivity, turbidity and dissolved oxygen. Over one million data points