Energy Technology Data Exchange (ETDEWEB)

The regular occurrence of large-scale earthquakes in Japan necessitates the use of earthquake disaster prevention systems that focus on gathering damage information on gas supply facilities immediately after an earthquake strikes and minimizing the damage. This paper discussed the development of an earthquake damage estimation system for city gas pipelines that can show damage information in real-time by using earthquake records obtained from densely deployed earthquake observation networks and the most advanced telecommunication and information technologies. The paper summarized the earthquake damage estimation system (EDES) and Toho Gas disaster prevention measures. Specific topics that were discussed included the Toho Gas supply method; earthquake countermeasures; construction of computer systems; ...

Energy Technology Data Exchange (ETDEWEB)

Hyogo-ken Nanbu earthquake with a focus in the Akashi straits has given huge earthquake damages in and around Awaji Island and Kobe City in 1995. It is clear that the basement structure, which is steeply deepened at Kobe City from Rokko Mountains towards the coast, and the focus under this related closely to the local generation of strong ground motion. Generation process of the strong ground motion was discussed using 2D and 3D numerical simulation methods. The 3D pseudospectral method was used for the calculation. Space of 51.2km{times}25.6km{times}25.6km was selected for the calculation. This space was discretized with the lattice interval of 200m. Consequently, it was found that the basement structure with a steeply deepened basement, soft and weak geological structure thickly deposited on the basement, and earthquake faults running under the boundary of base rock and sediments related greatly to ...

Energy Technology Data Exchange (ETDEWEB)

In the development of the man-made island siting technology of nuclear power plants, assessing the stability of the seawall against large ocean waves and earthquakes is indispensable. Concerning with the seismic stability of the seawall, prediction of the deformation like sliding and settlement of the seawall during earthquake including the armour units in front of the caisson becomes important factor. For this purpose, the authors have developed the two-dimensional DEM-FEM coupled analysis method (SEAWALL-2D) to predict the deformation of the seawall covered with the armour units during earthquake. In this method, movements of the armour units are calculated in DEM analysis part and deformation of the caisson, rubble moundsand seabed and back fill are calculated in FEM analysis part taking the nonlinearity of the soil materials based on the effective stress into account. Numerical simulations of ...

Energy Technology Data Exchange (ETDEWEB)

There is a rapidly growing need to evaluate sensor network functionality and performance in the context of the larger environment of infrastructure and applications in which the sensor network is organically embedded. This need, which is motivated by complex applications related to national security operations, leads to a paradigm fundamentally different from that of traditional data networks. In the sensor networks of interest to us, the network dynamics depend strongly on sensor activity, which in turn is triggered by events in the environment. Because the behavior of sensor networks is sensitive to these driving phenomena, the integrity of the sensed observations, measurements and resource usage by the network can widely vary. It is therefore imperative to accurately capture the environmental phenomena, and drive the ...

CERN Document Server

Many mobile ad hoc network protocols use simple flooding, in order to adapt to changes in time varying network topology. Most of the times, a network-wide flood results in redundant packets and increases network congestion, probability of packet collision, low utilization of available bandwidth, and most important, higher power consumption. In this paper, we propose a new cross-layer broadcast scheme to minimize broadcast traffic in mobile ad hoc networks. Our scheme is based on use of received signal strength indicator, RSSI, value to reduce the number of broadcast packets. The effectiveness of the proposed technique is verified using simulations.

Science.gov (United States)

Aug 23, 2011 ... Earthquakes, Hurricanes and Stubborn Instruments ... And if earthquakes and stubborn instruments aren't enough, there's this giant hurricane ...

Science.gov (United States)

The Seismic Risk Explorer, an extension for ArcGIS Desktop developed by cedim AG, is a tool for computing the seismic risk, i.e. damage on residential buildings and thereby caused monetary losses for earthquake scenarios. It is based on the research results of the CEDIM (Center for Disaster Management and Risk Reduction Technology) research center, located at the Karlsruhe Institute of Technology (KIT) and the GeoForschungsZentrum (GFZ) in Potsdam. With this software tool seismic scenarios can be simulated for a given magnitude, depths and location. The seismic intensity, the resulting mean damage ratio for residential buildings and the seismic risk, expressed as the monetary loss caused by an earthquake can be computed downscaled to communities, postcode areas or even single buildings. Interested end-users are especially insurance companies, but also public authorities which may use the tool for risk management issues.

Transactions and Proceedings of the Royal Society of New Zealand 1868-1961

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International Nuclear Information System (INIS)

The layout of the network with its frequency and transmission power control shows how the time behaviour of power plants and consumers determines the frequency curve during sudden power disturbances. As for switching processes in the network for the turbine, network operation entails loads due to shock-like disturbance functions to which one should not normally respond by switching off. The interception controllers are therefore adjusted via a simulation model by which the vibrations of the turbine rotor can be modelled in real time under different network loads. (GL).

Science.gov (United States)

... one for each node, and an i/o queue to manage ... ecuted as if it came from a terminal attached to a ... In its default mode PC-NETSIM is stochastic, that is ...

CERN Document Server

During the last years, large-scale simulations of realistic physical environments which support the interaction of multiple participants over the Internet have become increasingly available and economically significant, most notably in the computer gaming industry. Such systems, commonly called networked virtual environments (NVEs), are usually based on a client-server architecture where for performance reasons and bandwidth restrictions, the simulation is partially deferred to the clients. This inevitable architectural choice renders the simulation vulnerable to attacks against the semantic integrity of the simulation: malicious clients may attempt to compromise the physical and logical laws governing the simulation, or to alter the causality of events a posteriori. In this paper, we initiate the systematic study of semantic integrity in NVEs from a security ...

Science.gov (United States)

University research group with research areas: * Land based and submersible autonomous robots, (UUVs: AUVs and ROVs); * Controllers, electronics, sensor design and fusion, motion control; * Guidance and navigation of underwater vehicles; * AI, neural networks, fuzzy logic, subsumption control, behaviour based control; * Optical fibre and ultrasonic sensors for proximal object detection; * Robot arm control, visual servoing; * Imaging sonar applications; * Simulator development: UUV simulator; imaging sonar simulator; Aircraft/flight simulator.

Science.gov (United States)

We present an image of the rupture propagation of the 2004 M6.0 Parkfield earthquake using records from a dense network of local strong motion stations. We back-propagate high-frequency waveforms in 3D with a method, similar to reverse time migration, to obtain an estimate of the distribution of radiated high-frequency seismic energy in space and time. The image is forced to be coherent at the known hypocenter location and the quake origin time by applying small static time shifts obtained using waveform cross-correlation. We observe that the Parkfield earthquake radiated a distinct secondary high-frequency phase, which is located about 12.5~km northwest of the hypocenter with an onset of seismic radiation about 5~s after the rupture initiation. The time history of the back-projection suggests a rupture velocity of 2.5~km/s between hypocenter and subevent. The back-projection result is confirmed by inversion of picked ...

DEFF Research Database (Denmark)

This thesis - Resource Management in Broadband Communication Networks - deals with different ways of optimizing the available resources of data- or telecommunication networks. Especially topics like optimal routing, load balancing and fast recovery of routes in case of link failures are covered. The first part gives a brief description of some of the existing protocols for routing and controlling resources, such as RSVP, OSPF, BGP, PNNI, etc. The remaining part concerns the following two fundamentally different approaches to resource management etc.: - Software agents - Simulated ants In the beginning of the part concerning software agents a description of what exactly constitutes software agents, according to the scientists and according to the organization, FIPA is given. After this, the main results from the IMPACT project are presented. The IMPACT project is an EU-project that aimed at developing a demonstration ...

Energy Technology Data Exchange (ETDEWEB)

Although state estimation is a mature technique which is widely available in the EMS industry, experience with practical implementation and use of state estimation and network security analysis functions at electric power utilities over the last two decades indicates recurring difficulties and problems attributable to inadequate external network modeling detail and data. This paper addresses the development of a set of guidelines for external network modeling and data exchange, based on the results of a recent project sponsored by EPRI. A general methodology is developed based on the results of a survey of a representative set of utilities and EMS suppliers, supplemented by subsequent analysis and simulation studies. Distinction is made between guidelines pertaining to external network topology, analog measurements, data exchange, and implementation procedures. A philosophy and ...

CERN Document Server

We have conducted an agent-based simulation of chain bankruptcy. The propagation of credit risk on a network, i.e., chain bankruptcy, is the key to nderstanding largesized bankruptcies. In our model, decrease of revenue by the loss of accounts payable is modeled by an interaction term, and bankruptcy is defined as a capital deficit. Model parameters were estimated using financial data for 1,077 listed Japanese firms. Simulations of chain bankruptcy on the real transaction network consisting of those 1,077 firms were made with the estimated model parameters. Given an initial bankrupt firm, a list of chain bankrupt firms was obtained. This model can be used to detect high-risk links in a transaction network, for the management of chain bankruptcy.

International Nuclear Information System (INIS)

The dynamic response of thin liquid storage tanks to earthquakes is a very complicated phenomenon, because it can be highly non linear. Among others, one can meet material and geometric non linearities of the tank shell leading eventually to static or dynamic buckling non linear behavior of anchor bolts, contact non-linearities due to the uplift of the tank base and to the unilateral character of the fluid pressure on the shell and high amplitude fluid oscillations. Moreover, linear or non linear soil structure interaction affects considerably the response of the fluid structure system under consideration. In this paper we focus attention on problems related only to the base uplift and anchors plastification. We study a tank similar to the Hualien project tank, but we neglect the soil structure interaction. The studied tank is representative of medium height to radius ratio ratio tanks with relatively thick bottom plate. The contact is ...

UK PubMed Central (United Kingdom)

Epidemics are frequently simulated on redundantly wired contact networks, which have many more links between sites than are minimally required to connect all. Consequently, the modelled pathogen can...Full Text Available

UK PubMed Central (United Kingdom)

We use a novel normal mode analysis of an elastic network model drawn from configurations generated during microsecond all-atom molecular dynamics simulations to analyze the mechanism of auto-inhibition...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

The Advanced Simulation and Computing (ASC) Distance Computing (DisCom) Wide Area Network (WAN) is a high performance, long distance network environment that is based on the ubiquitous TCP/IP protocol set. However, the Transmission Control Protocol (TCP) and the algorithms that govern its operation were defined almost two decades ago for a network environment vastly different from the DisCom WAN. In this paper we explore and evaluate possible modifications to TCP that purport to improve TCP performance in environments like the DisCom WAN. We also examine a much newer protocol, SCTP (Stream Control Transmission Protocol) that claims to provide reliable network transport while also implementing multi-streaming, multi-homing capabilities that are appealing in the DisCom high performance network environment. We provide performance comparisons and recommendations for ...

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CERN Document Server

In this paper we present a model and simulator for many clusters of heterogeneous PCs belonging to a local network. These clusters are assumed to be connected to each other through a global network and each cluster is managed via a local scheduler which is shared by many users. We validate our simulator by comparing the experimental and analytical results of a M/M/4 queuing system. These studies indicate that the simulator is consistent. Next, we do the comparison with a real batch system and we obtain an average error of 10.5\\% for the response time and 12\\% for the makespan. We conclude that the simulator is realistic and well describes the behaviour of a large-scale system. Thus we can study the scheduling of our system called \\dirac in a high throughput context. We justify our decentralized, adaptive and opportunistic approach in comparison to a ...

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CERN Document Server

Numerical simulations are used to test the kinetic theory constitutive relations of inertial granular shear flow. These predictions are shown to be accurate in the dilute regime, where only binary collisions are relevant, but underestimate the measured value in the dense regime, where force networks of size $\\xi$ are present. The discrepancy in the dense regime is due to non-collisional forces that we measure directly in our simulations and arise from elastic deformations of the force networks. We model the non-collisional stress by summing over all paths that elastic waves travel through force networks. This results in an analytical theory that successfully predicts the stress tensor over the entire inertial regime without any adjustable parameters.

British Library Electronic Table of Contents (United Kingdom)

Global supply chain practices and their effects have received considerable attention over the last two decades. In the recent past, the need for integration across supply chains has been identified as a key for effective and efficient operations of supply chains. This is observed with the increasing trend of collaborative partnerships among supply chain partners. This paper presents an integrated approach for manufacturing and distribution networks within the supply chain system of a global car company. The paper shows that the integration of manufacturing and distribution networks creates the environment for effective planning of many components and execution/follow-up of those plans. These components include materials, resources, operations/activities, suppliers and customers. The main f...

Energy Technology Data Exchange (ETDEWEB)

CommAspen is a new agent-based model for simulating the interdependent effects of market decisions and disruptions in the telecommunications infrastructure on other critical infrastructures in the U.S. economy such as banking and finance, and electric power. CommAspen extends and modifies the capabilities of Aspen-EE, an agent-based model previously developed by Sandia National Laboratories to analyze the interdependencies between the electric power system and other critical infrastructures. CommAspen has been tested on a series of scenarios in which the communications network has been disrupted, due to congestion and outages. Analysis of the scenario results indicates that communications networks simulated by the model behave as their counterparts do in the real world. Results also show that the model could be used to analyze the economic impact of communications congestion and outages.

Science.gov (United States)

125 Years of Science for America - 1879 to 2004 link to Western Coastal and Marine Geology website U.S. Geological Survey Professional Paper 1687 Marine Geology and Earthquake...

UK PubMed Central (United Kingdom)

The devastating earthquake in Sichuan, China on 12 May 2008 left thousands of survivors requiring medical care and intensive rehabilitation. In view of this great demand, the Chinese Speaking Orthopaedic...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

The purpose of this project is to integrate a variety of geographic information systems capabilities and telecommunication technologies for potential use in geographic network and visualization applications. The specific technical goals of the project were to design, develop, and simulate the components of an audio/visual geographic communications system to aid future real-time monitoring, mapping and managing of transport vehicles. The system components of this feasibility study are collectively referred to as a Geographic Visualization and Communications System (GVCS). State-of-the-art techniques will be used and developed to allow both the vehicle operator and network manager to monitor the location and surrounding environment of a transport vehicle during shipment.

Science.gov (United States)

... Deepwater Horizon leak in the Gulf of Mexico, the Haitian earthquake and subsequent response, release of information by WikiLeaks, the Icelandic ...

CERN Document Server

Significant research has been carried out in the recent years for generating systems exhibiting intelligence for realizing optimized routing in networks. In this paper, a grade based twolevel based node selection method along with Particle Swarm Optimization (PSO) technique is proposed. It assumes that the nodes are intelligent and there exist a knowledge base about the environment in their local memory. There are two levels for approaching the effective route selection process through grading. At the first level, grade based selection is applied and at the second level, the optimum path is explored using PSO. The simulation has been carried out on different topological structures and it is observed that a graded network produces a significant reduction in number of iteration to arrive at the optimal path selection.

Energy Technology Data Exchange (ETDEWEB)

In this paper, a neural networks (NN) based adaptive sliding mode controller (SMC) is introduced. The selection of SMC feedback gains is normally based on one operating point and thus the performance of the controller away from the design operating point is, of necessity, a compromise. The adaptive SMC is proposed to overcome the limitations imposed on the effectiveness of the SMC under different operating conditions. Neural networks are used for online prediction of the optimal SMC gains when the operating point changes. The proposed method has been applied to a power system stabilizer (PSS) of a single machine power system. Simulation results are included to demonstrate the performance of the proposed control scheme.

British Library Electronic Table of Contents (United Kingdom)

This paper presents results from a research case study that examined the distribution of travel time of origin-destination (OD) pairs on a transportation network under incident conditions. Using a transportation simulation dynamic traffic assignment (DTA) model, incident on a transportation network is executed under normal conditions, incident conditions without traveler information availability, and incident conditions assuming that users had perfect knowledge of the incident conditions and could select paths to avoid the incident location. The results suggest that incidents have a different impact on different OD pairs. The results confirm that an effective traveler information system has the potential to ease the impacts of incident conditions network wide. Yet it is also important to n...

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Local access network technologies

British Library Electronic Table of Contents (United Kingdom)

The effects of thermal radiation and viscous dissipation on magneto-hydrodynamic (MHD) unsteady free-convection flow over a semi-infinite vertical porous plate are analysed. The fluid considered is non-gray (absorption coefficient dependent on wave length). The Network Simulation Method is used to solve the boundary-layer equations based on the finite-difference formulation; only discretization of the spatial co-ordinates is necessary, while time remains as a real continuous variable. This method provides a solution for both transient and steady-state problems at the same time, and programming does not require manipulation of the sophisticated mathematical software that is inherent in other numerical methods. The velocity, temperature, local skin-friction and local Nusselt number are studi...

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Energy Technology Data Exchange (ETDEWEB)

This paper presents a method for analyzing the seismic response of a flat bottomed cylindrical liquid storage tank to vertical earthquake excitation. Here, vertical earthquake acceleration is considered to correspond to an increase in the density of a stored liquid. Taking into account the vertical and horizontal earthquake loads, hydrostatic pressure, and considering restrictive moment and shear forces at shell-bottom welded joint, the author has calculated circumferential and longitudinal stresses. These are combined to more accurately approximate the stresses at the base shell course. The calculated result closely conforms to the actual damage, termed ''elephant's foot,'' observed in the fuel storage tanks damaged in the Tangshan earthquake. This result shows that the ''elephant's foot'' phenomenon is not caused ...

Energy Technology Data Exchange (ETDEWEB)

Long-term disposal and management of low and intermediate-level radioactive waste is a major project of the nuclear power industry. Therefore, the selection of an underground waste repository has to be a geologically and seismologically stable storage. Easy transportation and emplacement is essential. The Wolsung nuclear power plant (NPP) of unit no. 1/2/ 3/ 4, which is responsible for the future of the energy industry, has already been constructed at the Wolsung site and a New NPP has recently been created at the Sinwolsung site. Radioactive waste used in the plant facilities, has piled up increasingly every year, but it should be taken to be managed at long-term underground storage disposal facilities. The Wolsung site for radioactivity waste repository was known to be relatively stable through various geological surveys, earthquakes, groundwater, engineering testing and analysis, but still more research related to the stability of the structure, in deep ...

Energy Technology Data Exchange (ETDEWEB)

We have performed a detailed analysis of water clustering and percolation in hydrated Nafion configurations generated by classical molecular dynamics simulations. Our results show that at low hydration levels H2O molecules are isolated and a continuous hydrogen-bonded network forms as the hydration level is increased. Our quantitative analysis has established a hydration level (?) between 5 and 6 H2O/SO3- as the percolation threshold of Nafion. We have also examined the effect of such a network on proton transport by studying the structural diffusion of protons using the quantum hopping molecular dynamics method. The mean residence time of the proton on a water molecule decreases by two orders of magnitude when the ? value is increased from 5 to 15. The proton diffusion coefficient in Nafion at a ? value of 15 is about 1.1x10-5 cm2/s in agreement with experiment. The results provide quantitative atomic-level evidence of ...

Energy Technology Data Exchange (ETDEWEB)

An objective methodology is presented for determining the number and disposition of ambient air-quality stations in a monitoring network for the primary purpose of compliance with air-quality standards. The methodology utilizes a data base with real or simulated data from an air quality dispersion model for application with a two-step process for ascertaining the optimal monitoring network. In the first step, the air-quality patterns in the data base are collapsed into a single composite pattern through a figure-of-merit (FOM) concept. The most-desirable locations are ranked and identified using the resultant FOM fields. In the second step the network configuration is determined on the basis of the concept of spheres of influence (SOI) developed from cutoff values of spatial-correlation coefficients between potential monitoring sites and adjacent locations. The minimum number of required stations is ...

Science.gov (United States)

Hayakawa et al. (2009) and Hayakawa (2011) have recently reviewed some "anomalous" ULF signatures in the geomagnetic field which previous publications have claimed to be earthquake precursors. The motivation of this review is "to offer a further support to the definite presence of those anomalies". Here, these ULF precursors are reviewed once again. This brief communication shows that the reviewed anomalies do not "increase the credibility on the presence of electromagnetic phenomena associated with an earthquake" since these anomalous signals are actually caused by normal geomagnetic activity. Furthermore, some of these ULF precursors have just been rebutted by previous publications.

Energy Technology Data Exchange (ETDEWEB)

This paper describes the structure of dynamic neuronal ensembles (DNEs). DNEs represent a new paradigm for learning, based on biological neural networks that use variable structures. We present a computational neural element that demonstrates biological neuron functionality such as neurotransmitter feedback absolute refractory period and multiple output potentials. More specifically, we will develop a network of neural elements that have the ability to dynamically strengthen, weaken, add and remove interconnections. We demonstrate that the DNE is capable of performing dynamic modifications to neuron connections and exhibiting biological neuron functionality. In addition to its applications for learning, DNEs provide an excellent environment for testing and analysis of biological neural systems. An example of habituation and hyper-sensitization in biological systems, using a neural circuit from a snail is presented and discussed. This paper ...

Energy Technology Data Exchange (ETDEWEB)

In the present scenario of market driven business, power supply has become more like a commodity. Reliable and quality power need to be ensured to meet customer requirements. In such a situation, it is extremely important that transmission line faults be identified accurately, reliably and in quick time. Advanced signal processing tools such as discrete wavelet transform (DWT) can be used very effectively for parameterisation and characterization of the fault signals. On the other hand, properly configured neural network (NN) can be utilized for classification of the faults based on the DWT signal. The present contribution uses electromagnetic transient program (EMTP) for modeling of a real transmission system and MATLAB for DWT and NN. Various types of faults have been simulated at different locations along the transmission line and an attempt has been made to correctly identify and locate the fault. (author)

Energy Technology Data Exchange (ETDEWEB)

A power system stabilizer based on GMV (Generalized Minimum Variance), one of the adaptive control techniques, is developed to enhance the dynamic performances of a power system using an Artificial Neural Network (ANN). The stabilizer consists of two parts. One part is Inverse Dynamics Neural Networks (IDNN), which is trained to identify the inverse dynamics of controlled plant and used as a one-step ahead controller, or inverse controller. The other part is Adaptive Reference Model (ARM), which prevents excessive controller output. The ARM produces the modified reference value by minimizing a cost function recursively on the assumption that the IDNN perfectly identifies the controlled plant. The IDNN is used in the minimization procedure to calculate the sensitivities. The proposed controller is simulated in a typical one-machine-infinite-bus power system to show its effectiveness to damp sustained low frequency ...

Energy Technology Data Exchange (ETDEWEB)

In this study, the two methods, US NRC and JAERI method, for the determination of scenario earthquakes for seismic design of nuclear power plants based on the probabilistic seismic hazard analysis were reviewed. The scenario earthquakes were developed for the Wolsung NPP site using the PSHA results based on the US NRC Regulatory Guide 1.165 procedures. It seems that the JAERI method is more appropriate to incorporate the effects of individual seismic sources and active faults, and to estimate the multiple ground motion parameters. The magnitude and distance bins of the scenario earthquakes for Wolsung NPP site were M6.4, 9km and M6.2, 13km.

Science.gov (United States)

Mar 2, 2010 ... The NASA/JPL Education Office works with educators -- both classroom teachers and informal educators -- to provide tools, resources and ...

Science.gov (United States)

We develop a 3-D model to simulate the synthetic aperture radar (SAR) image formation process of an undulated vegetation canopy such as corn grown in fields with large periodic drainage reliefs. We explain how the simulated SAR image of undulated vegetation medium is obtained by the convolution of a 2-D slice of the 3-D simulated SAR system point spread function [(PSF), emulating the SAR beam modeled by a cosine modulated Gaussian], with the 2-D projection of the observed undulated vegetation canopy (modeled with scatterers randomly distributed in 3-D undulated space) followed by the extraction of each look envelope, the summation of looks, and sampling in azimuthal and range directions. Our model is useful to study the parameters involved in the formation and the analysis of SAR images of undulated vegetation medium. Validation of simulations made with actual SAR images shows that undulated corn crop ...

Science.gov (United States)

... ADVANCED NETWORK SECURITY PROJECT Indiana University ... 4. TITLE AND SUBTITLE ADVANCED NETWORK SECURITY PROJECT ...

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Energy Technology Data Exchange (ETDEWEB)

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Science.gov (United States)

PMID:10175525

Energy Technology Data Exchange (ETDEWEB)

Eaton, in partnership with Oak Ridge National Laboratory and the Electric Power Research Institute (EPRI) has completed a project that applies a combination of wireless sensor network (WSN) technology, anticipatory theory, and a near-term value proposition based on diagnostics and process uptime to ensure the security and reliability of critical electrical power infrastructure. Representatives of several Eaton business units have been engaged to ensure a viable commercialization plan. Tennessee Valley Authority (TVA), American Electric Power (AEP), PEPCO, and Commonwealth Edison were recruited as partners to confirm and refine the requirements definition from the perspective of the utilities that actually operate the facilities to be protected. Those utilities have cooperated with on-site field tests as the project proceeds. Accomplishments of this project included: (1) the design, modeling, and simulation of the anticipatory wireless sensor ...

Science.gov (United States)

The behavior of a small power system consisting of two interconnected generators is simulated in real-time by a prototype Digital Transient Network Analyzer (TNA). The prototype Digital TNA consists of two Computational Modules and one I/O Module. The Modules communicate with each other through ribbon cables. Each Computational Module simulates one Turbo-Generator, its Transformer, its Governor, Exciter, and Power System Stabilizer Systems. The numerical integration is shared by two TMS320C30 DSPs at a step-size of 100 microseconds in real-time. The I/O module post-processes the state variables and presents selected information for analog display. The paper presents oscillograms from a test program which includes symmetry checks and behavioral checks against well known waveforms of hunting oscillations, synchronization out-of-phase torques, and subsynchronous resonance phenomena. The success of the Digital TNA depends on: ...

Energy Technology Data Exchange (ETDEWEB)

A radon detector with LR-115 nuclear track film was constructed for radon concentration measurements in soil. Temporal radon variations, as well as the barometric pressure, precipitation and temperature were measured for two years. Negative correlation between radon concentration in soil and barometric pressure was found. For some of the recorded earthquakes that occurred during the observation period, soil radon anomalies may be noticed one month before the quakes.

Energy Technology Data Exchange (ETDEWEB)

The long-range correlation properties in the hourly time variability of geochemical signals measured in a 70 m depth well at Triponzo (Umbria region), are investigated by the detrended fluctuation analysis (DFA). DFA is a data processing method that allows for the detection of scaling behaviors in observational time series even in the presence of non-stationarities. The procedure adopted has allowed for the unambiguous identification of possible correlations among the recorded signals and local earthquakes.

British Library Electronic Table of Contents (United Kingdom)

In the present contribution, the innovative in situ Raman micro-spectroscopy was applied to investigate the in vitro reactivity of various bioactive glasses. All the investigated glasses belonged to the Na2O\\K2O-CaO-P2O5-SiO2 system, but contained sensibly different percentages of network modifiers. The glasses were immersed for increasing times, up to 96h, in simulated body fluid (SBF) and in tris-buffered (TRIS) solution. In this way, two fundamental items were addressed, i.e. the effect of the glass composition and the nature of the soaking fluid on the overall reactivity. As regards the SBF, all the glasses were able to promote the formation of a hydroxyl-carbonate apatite (HCA) surface layer in very short times. The reaction rate was particularly quick for the 45S5 Bioglass and for it...

CERN Document Server

Networked Digital Library of Theses and Dissertations

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This paper presents a supernetwork equilibrium model integrating supply chain networks with a transport network, namely, a supply chain-transport supernetwork equilibrium model. The model takes into account the behaviour of freight carriers and transport network users to endogenously determine the transport costs generated in the supply chain networks. The interaction between transport network and supply chain networks can also be examined. Results of the numerical tests reveal that the improvement of transport network could enhance the efficiency of supply chain networks. The paper makes contributions to modelling of supply chain networks as well as to that of transport networks.

Energy Technology Data Exchange (ETDEWEB)

Artificial neural network analysis is found to be far superior to multiple regression when applied to the evaluation of trap quality in the Northern Kuqa Depression, a gas-rich depression of Tarim Basin in western China. This is because this technique can correlate the complex and non-linear relationship between trap quality and related geological factors, whereas multiple regression can only describe a linear relationship. However, multiple regression can work as an auxiliary tool, as it is suited to high-speed calculations and can indicate the degree of dependence between the trap quality and its related geological factors which artificial neural network analysis cannot. For illustration, we have investigated 30 traps in the Northern Kuqa Depression. For each of the traps, the values of 14 selected geological factors were all known. While geologists were also able to assign individual trap quality values to 27 traps, they were less certain ...

Energy Technology Data Exchange (ETDEWEB)

Methods, systems, and products are disclosed for determining a bisection bandwidth for a multi-node data communications network that include: partitioning nodes in the network into a first sub-network and a second sub-network in dependence upon a topology of the network; sending, by each node in the first sub-network to a destination node in the second sub-network, a first message having a predetermined message size; receiving, by each node in the first sub-network from a source node in the second sub-network, a second message; measuring, by each node in the first sub-network, the elapsed communications time between the sending of the first message and the receiving of the second message; selecting the longest elapsed communications time; and calculating the bisection bandwidth ...

International Nuclear Information System (INIS)

The moderate earthquake of magnitude 5.2 was occurred at the offshore Uljin on the 29 May 2004. The magnitude of the event is the largest one which is equal to that of the Sokrisan earthquake on the 16 September 1978 since the beginning of the instrumental recording by the Korean Metrological Administration (KMA) in 1978. The magnitude of the event was large enough to be felt in a wide area of the southern Korea. It did not affect the safety of the Uljin nuclear power plant (NPP) site which is about 80 km away from the epicenter. In this article, we estimate source parameters of the event and evaluate preliminary seismic safety of the Uljin NPP site regarding the event as an empirical Green's function (EGF)

International Nuclear Information System (INIS)

During the 2007 Niigataken Chuetsu-oki earthquake, strong ground motion with the peak acceleration of 680 cm/s/s which was larger than that of the empirical prediction was recorded at the base mat of the No.1 reactor building of Kashiwazaki-Kariwa Nuclear Power Station (NPS). Furthermore, in the Kashiwazaki-Kariwa NPS, over twice difference of 680 vs. 322 cm/s/s of peak acceleration between the No.1 and the No.6 reactor buildings was observed on the base mat. From the results of recent research, it is suggested that the deep sedimentary layers can be one of the important factors to elucidate these phenomena. In this study, at first, the applicability of microtremor array measurements for estimation of deep S-wave velocity structure (#approx#Vs=3 km/s layer) are discussed. Vertical microtremors were observed in three arrays at the Kashiwazaki-Kariwa NPS with the maximum station spacings of 3.04 km, 1.49 km and 0.75 km, respectively. The Rayleigh wave phase velocity ...

Science.gov (United States)

... MTR 93B0000095 Proposed Network Security Policy for Integrated Tactical Warning ... Proposed Network security Policy for Integrated Tactical ...

Science.gov (United States)

... AFIT/CI "OVERPRINT" Page 2. NETWORK SECURITY ISSUES by ... Page 4. Sinisi, Michael Jude (MS, Telecommunications) Network Security Issues ...

Science.gov (United States)

Page 1. Dynamic Virtual LANs for Adaptive Network Security ... Dynamic Virtual LANs for adaptive network security D. Merani, A. Berni, M. Leonard ...

CERN Document Server

Containing an epidemic at its origin is the most desirable mitigation. Epidemics have often originated in rural areas, with rural communities among the first affected. Disease dynamics in rural regions have received limited attention, and results of general studies cannot be directly applied since population densities and human mobility factors are very different in rural regions from those in cities. We create a network model of a rural community in Kansas, USA, by collecting data on the contact patterns and computing rates of contact among a sampled population. We model the impact of different mitigation strategies detecting closely connected groups of people and frequently visited locations. Within those groups and locations, we compare the effectiveness of random and targeted vaccinations using a Susceptible-Exposed-Infected-Recovered compartmental model on the contact network. Our simulations show that the targeted ...

Energy Technology Data Exchange (ETDEWEB)

Feed-forward (FF) artificial neural networks (ANN) and radial basis function (RBF) ANN methods were addressed for evaluating the lightning performance of high voltage transmission lines. Several structures, learning algorithms and transfer functions were tested in order to produce a model with the best generalizing ability. Actual input and output data, collected from operating Hellenic high voltage transmission lines, as well as simulated output data were used in the training, validation and testing process. The aims of the paper are to describe in detail and compare the proposed FF and RBF ANN models, to state their advantages and disadvantages and to present results obtained by their application on operating Hellenic transmission lines of 150kV and 400kV. The ANN results are also compared with results obtained using conventional methods and real records of outage rate showing a quite satisfactory agreement. The proposed ANN methods can be ...

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... Austrian Environment Minister Nikolaus Berlakovich called for such stress tests on Sunday (13 March) to make sure that nuclear power stations were quake-proof following Japan's massive earthquake and tsunami. Austria, a mountainous country rich in geothermal energy, has no NPPs and no plans to develop ...

Science.gov (United States)

An understanding of the mechanism of generation of Lg from underground nuclear explosions is essential for seismic monitoring and source discrimination. Near-source scattering of explosion-generated Rg into S appears to be responsible for the low-frequenc...

International Nuclear Information System (INIS)

The risk analysis was carried out in consideration of conditions prevailing at the Kalkar site analogous to the investigations in phase A of DRS (German Reactor Study). Earthquake design loads include the probabilities of upper deviations of the site intensities to be expected. The calculations of dynamic loads for select buildings are made using models and computational methods. Component analyses were performed analogous to DRS for the supports of large components, supports of the roof construction of the reactor building taking into account support reserves due to plastic work capacity, wall disks in steam generator buildings and switchboard plant buildings. (DG).

Science.gov (United States)

No abstract prepared.

Energy Technology Data Exchange (ETDEWEB)

Short communication.

UK PubMed Central (United Kingdom)

We study the statistical properties of a variety of diverse real-world networks. We present evidence of the occurrence of three classes of small-world networks: (a) scale-free networks,...Full Text Available

CERN Document Server

The network utility maximization (NUM) problem for multi-path is a problem which is non-strictly convex and non-separable. Using Jensen's inequality, we approximate the NUM to a strictly convex and separable problem which can be solved efficiently by the dual decomposition method. After a series of approximations, the result of the approximation problem converges to the globally optimal solution of the original NUM. Moreover, because of the separable and dual-based natures of the proposed algorithm, we utilize the reverse engineering frameworks of the current TCPs to develop a series of multi-path TCPs which are totally compatible with current TCPs. The multi-path users using our protocols can run simultaneously with the single-path users using the current TCPs. The simulations of our Multi-path Reno on ns-2 show the compatibility and the fairness among multi-path and single-path users.

Energy Technology Data Exchange (ETDEWEB)

The paper presents an alternative approach for the studies of high voltage transmission lines based on artificial intelligence and more specifically artificial neural networks (ANNs). In contrast to the existing conventional-analytical techniques and simulations which are using in the calculations empirical and/or approximating equations, this approach is based only on actual field data and actual measurements. The proposed approach is applied on high voltage transmission lines in order to calculate the lightning outages, on grounding systems in order to assess the grounding resistance and on high voltage transmission lines' polluted insulators in order to estimate the critical flashover voltage. The obtained results are very close to the actual ones for all three case studies, something which clearly implies that the ANN approach is well working and has an acceptable accuracy, constituting an additional tool of electric engineers. ...

Energy Technology Data Exchange (ETDEWEB)

This paper describes the weekly load forecasting expert system (named WLoFy) which was developed and implemented for korea electric power corporation(KEPCO). WLoFy was designed to provide user oriented features with a graphical user interface to improve the user interaction. The various forecasting models such as exponential smoothing, multiple regression, artificial neural networks, rule-based model, and relative coefficient model also have been included in WLofy to increase the forecasting accuracy. The simulation based on historical data shows that the weekly forecasting results from WLoFy is an improvement when compared to the results from the conventional methods. Especially the forecasting accuracy on special days has been improved remarkably. (author). 9 refs., 5 figs., 6 tabs.

Energy Technology Data Exchange (ETDEWEB)

An artificial neural network (ANN), trained as an inverse of the controlled plant, to function as a power system stabilizer (PSS) is presented in this paper. In order to make the proposed ANN PSS work properly, it was trained over the full working range of the generating unit with a large variety of disturbances. Data used to train the ANN PSS consists of the control input and the synchronous machine response with an adaptive PSS (APSS) controlling the generator. During training, the ANN was required to memorize the reverse input/output mapping of the synchronous machine. After the training, the output of the synchronous machine was applied as the input of the ANN PSS and the output of the ANN PSS was used as the control signal. Simulation results show that the proposed ANN PSS can provide good damping of the power system over a wide operating range and significantly improve the system performance.

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... analyze importance sampling schemes for stochastic networks ... an interesting mixed open/closed queueing network ... with a suitable terminal condition ...

Science.gov (United States)

... Accession Number : ADA060007. Title : Issues in Computer Network Security. Descriptive Note : Technical rept.,. Corporate ...

Science.gov (United States)

Promises of ubiquitous control of the physical environment by large-scale wireless sensor networks

Science.gov (United States)

Page 1. Adaptive system and method for responding to computer network security attacks Abstract A dynamic network security ...

Energy Technology Data Exchange (ETDEWEB)

Sandia National Laboratories has recently developed two major field test capabilities for unattended ground sensor systems at the Department of energy`s Nevada Test Site (NTS). The first capability utilizes the NTS large area, varied terrain, and intrasite communications systems for testing sensors for detecting and tracking vehicular traffic. Sensor and ground truth data can be collected at either of two secure control centers. This system also includes an automated ground truth capability that consists of differential Global Positioning Satellite (GPS) receivers on test vehicles and live TV coverage of critical road sections. Finally there is a high-speed, secure computer network link between the control centers and the Air Force`s Theater Air Command and Control Simulation Facility in Albuquerque NM. The second capability is Bunker 2-300. It is a facility for evaluating advanced sensor systems for monitoring activities in underground ...

CERN Document Server

Classical control theory has played a major role in the development of present-day technologies. Likewise, recently developed quantum optimal control methods can be applied to emerging quantum technologies, e.g. quantum information processing -- until now, at the level of a few qubits. However, such methods encounter severe limits when applied to many-body quantum systems: due to the complexity of simulating the latter, existing quantum control algorithms (requiring many iterations to converge) usually fail to yield a desired final state within an acceptable computational time. In contrast, we present here a strategy for controlling a vast range of non-integrable one-dimensional systems that is efficiently applicable to quantum many-body systems, as it can be merged with state-of-the-art tensor network simulation methods like the Density Matrix Renormalization Group. To demonstrate its potential, we employ it to solve a ...

Energy Technology Data Exchange (ETDEWEB)

Seismic monitoring at the Las Tres Virgenes, BCS, geothermal field started in 1992 with an analog station of vertical components detecting a large number of earthquakes of varying magnitudes. In February 1993, a seismic network was installed, composed of six digital stations DR-2000-with S-6000 and S-5000 sensors and three registration channels (N-S, E-W and vertical). This was the basis for the development of a program to correct arrival-time data for P and S waves due to instrument drift. From January to April 1994 and May to August 1995, based on the 170 seismic events recorded, a velocity model was proposed. From December 1995 to July 1996, seismic data were processed and interpreted, and zones of occurrence were determined for events according to magnitude and the predominant noise in the field. From September 2003 to December 2004, 10 seismic stations (permanent and temporary) were installed and monitored and it was concluded the most ...

Energy Technology Data Exchange (ETDEWEB)

A typical incident response pits technicians against networks that aren't prepared forensically. [1, 2] If practitioners do consider collecting network forensic data, they face a choice between expending extraordinary effort (time and money) collecting forensically sound data, or simply restoring the network as quickly as possible. In this context, the concept of organizational network forensic readiness has emerged. This paper proposes a methodology for "operationalizing" organizational network forensic readiness. The methodology, and the theoretical analysis that led to its development, are offered as a conceptual framework for thinking about more efficient, proactive approaches to digital forensics on networks.

CERN Document Server

Integrated femtocell/macrocell networks, comprising a conventional cellular network overlaid with femtocells, offer an economically appealing way to improve coverage, quality of service, and access network capacity. The key element to successful femtocells/macrocell integration lies in its self-organizing capability. Provisioning of quality of service is the main technical challenge of the femtocell/macrocell integrated networks, while the main administrative challenge is the choice of the proper evolutionary path from the existing macrocellular networks to the integrated network. In this article, we introduce three integrated network architectures which, while increasing the access capacity, they also reduce the deployment and operational costs. Then, we discuss a number of technical issues, which are key to making such integration a ...

Science.gov (United States)

This manual is intended to provide a free resource on essential network security concepts for non-technical managers of small libraries. Managers of other small nonprofit or community organizations will also benefit from it. An introduction defines network security; outlines three goals of network security; discusses why a library should be concerned with network security; and describes limits of this work. The manual is divided into three main parts. Part One features the management issues related to network security: analyzing risk, developing a security plan and policy, the funding requirements libraries can expect in operating their networks, and implementing adequate security. Part Two describes the areas of computer networks that need to be secured, and provides a description of many of the security measures necessary for adequate ...

International Nuclear Information System (INIS)

The Chuetsu-oki Earthquake strongly shook the Kashiwazaki-Kariwa Nuclear Power Station with the ground motions exceeding the design values. The incidents include a fire breakout of the Unit 3 transformer, a release of spilled water containing small amount of radioactive materials to the non-radiation control area and subsequently to the environment at Unit 6, and a release of radioactive material from the main turbine condenser through the main stack of Unit 7 due to the delay stooping the turbine gland steam ventilator by the operator in manually, while every unit in operation was safety shutdown in the automatic mode ensuring the three fundamental safety functions of (a) reactivity control, (b) removal of heat from the core and (c) confinement of radioactive materials. Following integrity evaluation and performance testing of the overall plant, seismic safety of buildings, structures, equipment and pipelines on the basis of the basic ...

Energy Technology Data Exchange (ETDEWEB)

An overview of BC Hydro`s review of its overhead transmission system to withstand earthquakes and its program of seismic upgrading, including the upgrading of tower pile foundations in liquefiable soils, was presented. BC Hydro`s system, geologic environment, seismic design criteria, investigations and analysis, treatment and alternatives and a case history of a seismic upgrade of a tall river crossing tower at the Pitt River in the Lower Mainland of B.C. were summarized. It was concluded that the inherent strength of towers, conductors, fittings and insulators was sufficient to withstand earthquakes. The towers most susceptible to slope and soil failure due to seismic activity were tall river crossing towers. It was suggested that soils investigations, seismicity, ground response, liquefaction and stability analyses be carried out at each site. The results of these tests would help to establish system seismic design criteria at each location. ...

British Library Electronic Table of Contents (United Kingdom)

Landslides on ancient embankments, burial mounds of Imashiro-zuka and Nishimotome-zuka, induced by historical earthquakes related to the tectonic movement of active fault systems located between northern Osaka and Kobe, are discussed. The geological conditions of the foundation of the mounds, the lithology, stiffness, and the position of the mound relative to the fault systems, contributed to the collapse of the mounds. Obvious interior structures of landslides revealed the inherent deformation process, and provided significant insight into landslide mechanisms. Rapid increasing pore water pressure was necessary to facilitate sliding along the almost horizontal slip surfaces developed in the main part of the landslide bodies on the Imashiro-zuka mound. Liquefaction analysis using both the ...

UK PubMed Central (United Kingdom)

This paper describes how a computerized MIS is used to assist HMO management to conduct utilization and quality of care review activities in a prepaid medical care network. The HMO is a ‘network’...Full Text Available

Science.gov (United States)

Materials World Network: Cooperative Activity in Materials Research between US Investigators and ... Program Title: Materials World Network: Cooperative Activity in Materials Research between US ...

Science.gov (United States)

Cyber attacks on a hospital's computer network is a new crime to be reckoned with. Should your hospital consider internet insurance? The author explains this new phenomenon and presents a risk assessment for determining network vulnerabilities. PMID:11951384

Energy Technology Data Exchange (ETDEWEB)

The role of computers has become increasingly important for oil and gas field research and operations support. Today, the computer network is an integral part of the increasingly complex computing environment that exists in many companies. Computer networks allow users to efficiently share information, software, and hardware to support critical global communication needs. Because users are able to share software and hardware, the use of computer networks can also result in significant cost savings. This paper describes typical network loading and demand levels for shared software applications on a computer network that has been used for several years.

Science.gov (United States)

'As part of the Computer Protection Plan, this Network Security Plan identifies the specific security measures used to protect Bechtel Hanford, Inc.'s (BHI's) enterprise network. The network consists of the communication infrastructure and information systems used by BHI to perform work related to the Environmental Restoration Contract (ERC) at the Hanford Site. It provides electronic communication between the ERC-leased facilities in Richland, Washington, and facilities located on the Hanford Site. Network gateways to other site and offsite networks provide electronic communication with the remainder of the Hanford community.'

Science.gov (United States)

5.2 Network Security. The features listed below can be used to help safeguard UNIX ...... The LaRCSCAN non-intrusive network security scanner package, ...

CERN Document Server

In this report, I surveyed the cognitive radio technique in wireless networks. Researched several kinds of cognitive techniques about their advantages and disadvantages.

Science.gov (United States)

NETWORK SECURITY, is revised to reflect, as item "g", incorporation ..... The Contractor shall provide support for the network security of the ...

Science.gov (United States)

... Accession Number : ADA298752. Title : Placement of Network Security Services for Secure Data Exchange. Descriptive Note : Final rept.,. ...

British Library Electronic Table of Contents (United Kingdom)

The tremendous growth of wireless technologies has introduced the potential of continuous service adaptation to the users' needs by giving them the ability to be able to select and access the proper network based on different criteria. Moreover, next generation wireless networks have been designed to provide support for multimedia services, with different traffic characteristics and different Quality of Service (QoS) guarantees. However, the expansion of Wireless Local Area Networks (WLANs) and Worldwide Interoperability for Microwave Access (WiMAX) networks poses new research era in the decision of the access network selection. In this paper, the existing access network selection schemes are classified into three categories: the network-centric, the user-centric and the collaborative sche...

Science.gov (United States)

... DTIC SELECTE z DEC 0 7, 1994 F THESIS NETWORK SECURITY AND THE NPS INTERNET FIREWALL by Jody L. Schivley September 1994 ...

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...Air Quality Monitoring Networks Products and Equipment Find and compare a variety of air quality monitoring networks products and equipment on the world's largest environmental industry portal. ...

Science.gov (United States)

Jan 22, 2011 ... Title: Model checking for network security requirements via a flexible modeling framework. Authors: Powell, J. Gilliam, D. ...

Science.gov (United States)

... California where he is currently working on an AS in. Data Communication & Network Management as well as Microsoft. MCSE and Cisco CCNA certifications.

Science.gov (United States)

A Composite Architecture for Network Security at JPL. Robert B. Mead, Tom G. Dearmond, and Joseph S. Sherif. JPL, California Institute of Technology ...

Energy Technology Data Exchange (ETDEWEB)

Leakage of CO{sub 2} and displaced brine from geologic carbon sequestration (GCS) sites into potable groundwater or to the near-surface environment is a primary concern for safety and effectiveness of GCS. The focus of this study is on the estimation of the probability of CO{sub 2} leakage along conduits such as faults and fractures. This probability is controlled by (1) the probability that the CO{sub 2} plume encounters a conductive fault that could serve as a conduit for CO{sub 2} to leak through the sealing formation, and (2) the probability that the conductive fault(s) intersected by the CO{sub 2} plume are connected to other conductive faults in such a way that a connected flow path is formed to allow CO{sub 2} to leak to environmental resources that may be impacted by leakage. This work is designed to fit into the certification framework for geological CO{sub 2} storage, which represents vulnerable resources such as potable groundwater, health and safety, and the near-surface ...

CERN Document Server

Regulatory genes called small RNAs (sRNAs) are known to play critical roles in cellular responses to changing environments. For several sRNAs, regulation is effected by coupled stoichiometric degradation with messenger RNAs (mRNAs). The nonlinearity inherent in this regulatory scheme indicates that exact analytical solutions for the corresponding stochastic models are intractable. Here, we present a variational approach to analyze a well-studied stochastic model for regulation by sRNAs via coupled degradation. The proposed approach is efficient and provides accurate estimates of mean mRNA levels as well as higher order terms. Results from the variational ansatz are in excellent agreement with data from stochastic simulations for a wide range of parameters, including regions of parameter space where mean-field approaches break down. The proposed approach can be applied to quantitatively model stochastic gene expression in complex regulatory ...

Energy Technology Data Exchange (ETDEWEB)

Soil contamination by liquid organic pollutants represents a serious threat to phreatic ground water. These organic liquids get into the ground and migrate through the porous medium until they finally reach the aquifer. After a critical study of the literature, we listed various existing multiple displacements under three-phase conditions of a disconnected polluting phase that may or not spread over water. The aim of this thesis is to model (at pore scale level) and integrate in the pore network model the various flows that occur when three phases (gas, pollutant and air) are present in a porous medium. The porous medium is supposed completely water-wet. The polluting phase may be connected or not, and the spreading coefficient of the pollutant over water may either be positive or negative. The goal of our study is to obtain macroscopic parameters such as relative permeabilities and capillary pressure. These parameters can be then incorporated in a larger-scale ...

International Nuclear Information System (INIS)

Model construction of the laboratory scale superconducting fault current limiter circuit (SFCL) has been performed. The SFCL is fault current limiter and used as electric network security. It mainly consists of a copper coil, a superconducting ring and an iron core that are concentrically arranged. The SFCL circuit is essentially a transformer where the secondary windings are being replaced by the ring of YBa_2Cu_3O_7_-_x superconductor (HTS). The ring has critical transition temperature Tc = 92 K and critical current Ic = 3.61 A. Characterization of the SFCL circuit is simulated by ANSYS version 5.4 software. The SFCL circuit consists of load and transformer impedances. The results show that the inductions of magnet field flux in the iron core of primer windings and ring disappear to one other before fault state. It means that impedance of the transformer is zero. After the condition a superconductivity behavior of the ring is disappear so ...

Energy Technology Data Exchange (ETDEWEB)

Stability concerns of the Par Pond Dam, an embankment structure in the Savannah River Site complex, resulted in a comprehensive evaluation of the state of its integrity. Specifically, excessive seepage through the embankment, slope failure due to an earthquake event as well as liquefaction potential of the embankment and the foundation are addressed and the potential of failure is evaluated. Lastly, remedial benefits of the addition of a berm structure are also assessed.

Science.gov (United States)

Cancer is a severe threat to human health. Early detection is considered the best way to increase the chance for survival. While the traditional cancer detection method, biopsy, is invasive, noninvasive optical diagnostic techniques are revolutionizing the way that cancer is diagnosed. Reflectance spectroscopy is one of these optical spectroscopy techniques showing promise as a diagnostic tool for pre-cancer detection. When a neoplasia occurs in tissue, morphologic and biochemical changes happen in the tissue, which in turn results in the change of optical properties and reflectance spectroscopy. Therefore, a pre-cancer can be detected by extracting optical properties from reflectance spectroscopy. This dissertation described the construction of a fiberoptic based reflectance system and the development of a series of modeling studies. This research is aimed at establishing an improved understanding of the optical properties of mucosal tissues by analyzing reflectance signals at ...

Science.gov (United States)

PMID:21398174

Science.gov (United States)

PMID:12556767

Science.gov (United States)

Not Available

Science.gov (United States)

Not Available

Medline Plus

... parent groups that are wonderful and lots of networking and a lot of interactions between the foundations, ...

Energy Technology Data Exchange (ETDEWEB)

Implementing a successful local area network for a publications work-group isn`t as simple as the scarcity of information on the subject would suggest. Making a network work for your requires careful planning, developing and acquiring network expertise, transforming your group`s patterns of working together, and carefully managing the human and technological resources.

Energy Technology Data Exchange (ETDEWEB)

This thesis investigates the application of artificial neural networks for the compression of image data. An algorithm is developed using the competitive learning paradigm which takes advantage of the parallel processing and classification capability of neural networks to produce an efficient implementation of vector quantization. Multi-Stage, tree searched, and classification vector quantization codebook design are adapted to the neural network design to reduce the computational cost and hardware requirements. The results show that the new algorithm provides a substantial reduction in computational costs and an improvement in performance.

Science.gov (United States)

Not Available

British Library Electronic Table of Contents (United Kingdom)

Recent supply chain reengineering efforts have focused on integrating firms? production, inventory and replenishment activities with the help of communication networks. While communication networks and supply chain integration facilitate optimization of traditional supply chain functions, they also exacerbate the information security risk: communication networks propagate security breaches from one firm to another, and supply chain integration causes breach on one firm to affect other firms in the supply chain. We study the impact of network security vulnerability and supply chain integration on firms? incentives to invest in information security. We find that even though an increase in either the degree of network vulnerability or the degree of supply chain integration increases the secur...

CERN Document Server

Mobile entities with wireless links are able to form a mobile ad-hoc network. Such an infrastructureless network does not have to be administrated. However, self-organizing principles have to be applied to deal with upcoming problems, e.g. information dissemination. These kinds of problems are not easy to tackle, requiring complex algorithms. Moreover, the usefulness of pure ad-hoc networks is arguably limited. Hence, enthusiasm for mobile ad-hoc networks, which could eliminate the need for any fixed infrastructure, has been damped. The goal is to overcome the limitations of pure ad-hoc networks by augmenting them with instant Internet access, e.g. via integration of UMTS respectively GSM links. However, this raises multiple questions at the technical as well as the organizational level. Motivated by characteristics of small-world networks that describe an ...

Energy Technology Data Exchange (ETDEWEB)

In this paper an attempt is made to forecast load using fuzzy neural network (FNN) for an integrated power system. Here, the proposed system uses a two stage FNN for a short term peak and average load forecasting (STPALF). The first stage FNN deals with the load forecasting and the second stage algorithm can be worked independently for network security. This technique is used to forecast load accurately on week days as well as holidays, weekends and some special occasions considering historical data of load and weather information and also take necessary control action for network security.

Energy Technology Data Exchange (ETDEWEB)

Use of a broadband Local Area Network (LAN) for transmission of classified and secure unclassified information requires monitoring capabilities which are sensitive to discrete segments of the network frequency spectrum. A viable monitoring system must be capable of detecting possible intrusion attempts or network malfunctions and alerting operating and security personnel. This report documents the results of an evaluation of the Magnavox CATV Systems Inc. Digital System Sentry software for network monitoring. Recommendations are made on its possible future role in broadband LAN security monitoring throughout the Nuclear Weapons Complex.

Energy Technology Data Exchange (ETDEWEB)

No abstract prepared.

Science.gov (United States)

Anthropogenic nitrogen (N) deposition affects many natural processes, including forest litter decomposition. Saprotrophic fungi are the only organisms capable of completely decomposing lignocellulosic (woody) litter in temperate ecosystems, and therefore the responses of fungi to N deposition are critical in understanding the effects of global change on the forest carbon cycle. Plant litter decomposition under elevated N has been intensively studied, with varying results. The complexity of forest floor biota and variability in litter quality have obscured N-elevation effects on decomposers. Field experiments often utilize standardized substrates and N-levels, but few studies have controlled the decay organisms. Decomposition of beech (Fagus sylvatica) blocks inoculated with two cord-forming basidiomycete fungi, Hypholoma fasciculare and Phanerochaete velutina, was compared experimentally under realistic levels of simulated N deposition at Wytham Wood, Oxfordshire, ...

International Nuclear Information System (INIS)

Research highlights: #-># The building occupancy affecting the cooling load prediction is studied. #-># PENN model is adopted in this study for predicting the building cooling load. #-># Statistical approach is adopted to result a less prejudice prediction performance. #-># Results show that occupancy data can significantly improve the prediction. -- Abstract: Building cooling load prediction is one of the key factors in the success of energy-saving measures. Many computational models available in the industry today have been developed from either forward or inverse modeling approaches. However, most of these models require extensive computer resources and involve lengthy computation. This paper discusses the use of data-driven intelligent approaches, a probabilistic entropy-based neural (PENN) model to predict the cooling load of a building. Although it is common knowledge that the presence and activity of building occupants have a significant impact on the required ...

Energy Technology Data Exchange (ETDEWEB)

Target recognition requires the ability to distinguish targets from non-targets, a capability called one-class generalization. Many neural network pattern classifiers fail as one-class classifiers because they use open decision boundaries. To function as one-class classifier, a neural network must have three types of generalization: within-class, between-class, and out-of-class. We discuss these three types of generalization and identify neural network architectures that meet these requirements. We have applied our one-class classifier ideas to the problem of automatic target recognition in synthetic aperture radar. We have compared three neural network algorithms: Carpenter and Grossberg`s algorithmic version of the Adaptive Resonance Theory (ART-2A), Kohonen`s Learning Vector Quantization (LVQ), and Reilly and Cooper`s Restricted Coulomb Energy network (RCE). The ART 2-A neural ...

Energy Technology Data Exchange (ETDEWEB)

A system and method for generating global asynchronous signals in a computing structure. Particularly, a global interrupt and barrier network is implemented that implements logic for generating global interrupt and barrier signals for controlling global asynchronous operations performed by processing elements at selected processing nodes of a computing structure in accordance with a processing algorithm; and includes the physical interconnecting of the processing nodes for communicating the global interrupt and barrier signals to the elements via low-latency paths. The global asynchronous signals respectively initiate interrupt and barrier operations at the processing nodes at times selected for optimizing performance of the processing algorithms. In one embodiment, the global interrupt and barrier network is implemented in a scalable, massively parallel supercomputing device structure comprising a plurality of processing nodes interconnected ...

CERN Document Server

We consider network coding for networks experiencing worst-case bit-flip errors, and argue that this is a reasonable model for highly dynamic wireless network transmissions. We demonstrate that in this setup prior network error-correcting schemes can be arbitrarily far from achieving the optimal network throughput. We propose a new metric for errors under this model. Using this metric, we prove a new Hamming-type upper bound on the network capacity. We also show a commensurate lower bound based on GV-type codes that can be used for error-correction. The codes used to attain the lower bound are non-coherent (do not require prior knowledge of network topology). The end-to-end nature of our design enables our codes to be overlaid on classical distributed random linear network codes. Further, we free internal nodes from ...

Energy Technology Data Exchange (ETDEWEB)

No abstract prepared.

CERN Document Server

Many real-world networks are so large that we must simplify their structure before we can extract useful information about the systems they represent. As the tools for doing these simplifications proliferate within the network literature, researchers would benefit from some guidelines about which of the so-called community detection algorithms are most appropriate for the structures they are studying and the questions they are asking. Here we show that different methods highlight different aspects of a network's structure and that the the sort of information that we seek to extract about the system must guide us in our decision. For example, many community detection algorithms, including the popular modularity maximization approach, infer module assignments from an underlying model of the network formation process. However, we are not always as interested in how a system's network ...

British Library Electronic Table of Contents (United Kingdom)

Purpose - The service-dominant (S-D) logic views supply chains as value co-creation networks. These networks promote knowledge growth amongst network members via resource deployment and coordination. The exchange of knowledge and utilization of operant resources among the network members leads to co-created service offerings and value proposals for the end-users, with the ultimate goal of transforming end-user experiences to perceptions of superior value-in-use. The purpose of this paper is to develop an illustration of the value co-creation concept and use this illustration as guide to examine the research gaps that are yet to be tapped in the area where supply chain networks and S-D logic intersects. Design/methodology/approach - The literature on S-D logic is reviewed and research gaps ...

International Nuclear Information System (INIS)

In this article, the ability of artificial neural networks in prediction of separation in steady two dimensional boundary layer flows is studied. Data for network training is extracted from numerical solution of an ODE obtained from Von Karman integral equation with approximate one parameter Pohlhousen velocity profile. As an appropriate neural network, a two layer radial basis generalized regression artificial neural network is used. The results shows good agreements between the overall behavior of the flow fields predicted by the artificial neural network and the actual flow fields for some cases. The method easily can be extended to unsteady separation and turbulent as well as compressible boundary layer flows. (author)

British Library Electronic Table of Contents (United Kingdom)

The recent literature in the field of supply chain management emphasizes the role of inter-organizational networks and the integration of vertical reproduction networks (supply chains) in particular as a key factor for value creation. However, the literature includes little empirical evidence. This situation suggests the need to appraise investments in such networks or supply chains carefully. How can a decision maker reliably assess the effect of investing in inter-organizational network arrangements on firm value? This article takes up this issue and suggests a framework consisting of five components to help answer the question. The task of the framework is to support the structuring and revelation of the causal chain between investments in the network on the one hand and the effect of t...

Energy Technology Data Exchange (ETDEWEB)

This paper presents the application of artificial neural networks to adiabatic flame temperature prediction of hydrocarbon fuels. The investigation was conducted over a wide range of operating conditions in terms of fuel composition, pressure and temperature of reactants, fuel-air equivalence ratio and fuel vapour fraction. Several neural network models for predicting the flame temperature for different applicable fuel ranges were built and examined. The proper preparation of network training data and the appropriate choice of network parameters for achieving better prediction accuracy are discussed. The neural network prediction results were compared with those calculated by a thermodynamic and chemical equilibrium-based computer code - the NASA program CET89. It was shown that trained neural network models can provide the adiabatic flame temperature prediction ...

Energy Technology Data Exchange (ETDEWEB)

Recent earthquake disasters have revealed the importance of countermeasures against soil Liquefaction in seismic design. In particular, the 1995 Hyogoken Nanbu earthquake caused several types of severe damages to pile foundations. This paper describes an analysis method for soil liquefaction using simple parameters such as SPT-N values and seismic response analyses for the pile-supported structure to consider soil-structure interaction effects and soil non-linearity using a modified Penzien model. It is important to find a way to determine the region of surrounding soil whose behavior is identical to that of piles. This paper adopts the thin layer element method to systematically determine the volume of the surrounding soil. The responses of pile-supported structure are similar, whether soil liquefaction and nonlinearity of pile are considered or not. However, the bending moment of pile become large as to soil liquefaction, and small as to ...

Energy Technology Data Exchange (ETDEWEB)

A 200 ft. tall stack, consisting of a concrete chimney with an independent acid proof brick liner built in the 1950`s, serving the Separations facility at the Savannah River Site (SRS), was evaluated for the performance category 3 (PC3) level of Natural Phenomena Hazards (NPH) effects. The inelastic energy absorption capacity of the concrete chimney was considered in the evaluation of the earthquake resistance, in particular, to compute the F{sub {mu}} factor. The calculated value of F{sub {mu}} exceeded 3.0, while the seismic demand for the PC3 level, using an F{sub {mu}} value of 1.5, was found to be less than the capacity of the concrete chimney. The capacity formulation of ACI 307 was modified to incorporate the effect of an after design opening on the tension side. There are considerable uncertainties in determining the earthquake resistance of the independent brick liner. The critical liner section, located at the bottom of the breeching ...

Energy Technology Data Exchange (ETDEWEB)

The objective of this project is to increase oil recovery from fractured reservoirs through improved fundamental understanding of the process of spontaneous imbibition by which oil is displaced from the rock matrix into the fractures. Spontaneous imbibition is fundamentally dependent on the reservoir surface free energy but this has never been investigated for rocks. In this project, the surface free energy of rocks will be determined by using liquids that can be solidified within the rock pore space at selected saturations. Thin sections of the rock then provide a two-dimensional view of the rock minerals and the occupant phases. Saturations and oil/rock, water/rock, and oil/water surface areas will be determined by advanced petrographic analysis and the surface free energy which drives spontaneous imbibition will be determined as a function of increase in wetting phase saturation. The inherent loss in surface free energy resulting from capillary instabilities at the microscopic (pore ...

Energy Technology Data Exchange (ETDEWEB)

The various technical aspects of radon concentration measurements in the ground or in the groundwater are reviewed. The emphasis is put on the most convenient techniques particularly suited for in situ monitoring in the field. Some attention is paid to the thoron problem. Historical and most recent findings in the field or earthquake related radon anomalies are presented and briefly discussed. A similar approach is made to rarer volcanic cases that have been documented up to now. A short discussion regarding the various models that intend to provide satisfactory explanations is presented, supported, whenever it is possible, by experimental laboratory results. Finally a glimpse on the possible and future application of the method to hydrogeology is given. (orig.).

Energy Technology Data Exchange (ETDEWEB)

It is important to accurately estimate the effects of strong earthquake motions on the basemat uplift behavior and structural responses for the seismic design of nuclear power plant buildings. In this paper, an analysis model which describes the soil part using the 3 dimensional FEM was proposed to be used when the ground contact ratio is low, and the validity of this model was confirmed. Furthermore, investigations using the model were carried out where the attaching force under the basemat was taken into account, in order to more realistically estimate the basemat uplift behavior. The effects in the case of the building being embedded were also investigated.

Energy Technology Data Exchange (ETDEWEB)

The end of 1994, five seismic observation stations were constructed with digital seismograph and 3-component seismometers. In this study, the epicentral distribution around the Kyungsang basin was obtained from one-year earthquake data (1994/12 - 1995/11) and compared with the annual earthquake report of KMA (Korea Meteorological Agency). The geological structure at the middle of the Ulsan fault was also investigated by the electrical resistivity method. The epicenters show high concentration at the Wolsung area. They show a linear alignment and their depths tend to be deeper as they approach to the coast line of the East Sea. These imply that they are probably correlated together. Another remarkable feature on land is the linear epicentral distribution along Jiri mountain to the Kimcheon and Sangju. This line is well coincident with newly recognized lineament. The other is the epicentral distribution at the Straits of Korea and East Sea. Even ...

UK PubMed Central (United Kingdom)

BackgroundInferring regulatory interactions between genes from transcriptomics time-resolved data, yielding reverse engineered gene regulatory networks, is of paramount importance...Full Text Available

Science.gov (United States)

In the late 1980's, the traditional threat of anonymous break-ins to networked computers was joined by viruses and worms, multiplicative surrogates that carry out the bidding of their authors. Technologies for authentication and secrecy, supplemented by good management practices, are the principal countermeasures. Four articles on these subjects are presented.

Wastenet

...of stations and a number of components, and meta information on air quality monitoring networks and stations. Access the database Producer Europe Environment Agency Content ...of stations and a number of components, and meta information on air quality monitoring networks and stations. Coverage National (Europe) Number of records...

Science.gov (United States)

ful application of the network technique, GERT, to the analysis of a terminal ... GERT Networks, Mr. David Gallagher-The Use of GERT in Studying Queueing Problems, ... Smith, R. L., "Stochastic Analysis of Personnel Movement in Formal ...

Science.gov (United States)

Page 1. Page 2. Page 3. Page 4. Page 5. Page 6. Page 7. Page 8. Page 9. Page 10. Page 11. Page 12. Page 13. Page 14. Page 15. Page 16. Page ...

UK PubMed Central (United Kingdom)

BackgroundA wide range of techniques is now available for analyzing regulatory networks. Nonetheless, most of these techniques fail to interpret large-scale transcriptional data...Full Text Available

UK PubMed Central (United Kingdom)

BackgroundGene expression profiling and the analysis of protein-protein interaction (PPI) networks may support the identification of disease bio-markers and potential drug targets....Full Text Available

UK PubMed Central (United Kingdom)

BackgroundModern approaches to treating genetic disorders, cancers and even epidemics rely on a detailed understanding of the underlying gene signaling network. Previous work has...Full Text Available

UK PubMed Central (United Kingdom)

PURPOSE We wanted to assess computer capabilities in a primary care practice-based research network and to understand how receptive the practices were to new ideas for automation of practice...Full Text Available

UK PubMed Central (United Kingdom)

Communication problems have been implicated in many safety and quality issues, but tools to examine communication networks and their impact on patient outcomes are only beginning to become available....Full Text Available

UK PubMed Central (United Kingdom)

BackgroundThe default mode network (DMN) is a set of brain regions that exhibit synchronized low frequency oscillations at resting-state, and is believed to be relevant to attention...Full Text Available

Science.gov (United States)

... Abstract : The acousto-optic filter (AOF) is ... for large switch networks. ... FOURIER TRANSFORMATION, OPTICAL SWITCHING, SURFACE ACOUSTIC ...

Science.gov (United States)

... more and better sensors to be ... all the continuously incoming data, which ... RANGE RECEIVER THERMAL CONDUCTIVITY ,# PRESSURE SENSOR ...

Science.gov (United States)

... the bound (5). For a network composed of a single source-terminal pair and ... Suboptimality bounds in stochastic control: A queueing example ...

British Library Electronic Table of Contents (United Kingdom)

This article introduces the story of Yusuf al-Marzuk (1895-1957), a Kuwaiti merchant who created a thriving network in the Arabian/Persian Gulf and India. This network was part of the vast, undocumented activities of Kuwaiti merchants. They were uncovered by rare British reports. Yusuf's economic power enabled him to participate in the struggle of Kuwaiti elites to achieve political power vis-a-vis the Kuwaiti rulers, the Sabah family. This article demonstrates the importance of the trading networks with respect to the economic and political developments that shaped the region before the relatively well researched oil period.

Science.gov (United States)

... from theory to practice will be significantly reduced while intrinsically revolutionizing the approach to engineering network security architectures. ...

Science.gov (United States)

General Meeting: NASA's biggest challenge: Education ... Turn right into the Police Association Facility at the crest of the first hill. ...

Medline Plus

... Resources and Links Kid's Newsletter Listserv's Grandparent's Newsletter Networking Personal Stories by Affected Kids & Adults (currently not ...

Science.gov (United States)

... 2004, Underwater Gliders for Ocean Research. Journal of the Marine Technology Society. Fiorelli, E., NE Leonard, P. Bhatta ...

International Nuclear Information System (INIS)

Supplementing the collection of artificial neural network methodologies devised for monitoring energy producing installations, a general regression artificial neural network is proposed for the identification of the two-phase flow that occurs in the coolant channels of boiling water reactors. The utilization of a limited number of image features derived from radiography images affords the proposed approach with efficiency and non-invasiveness. Additionally, the application of counter-clustering to the input patterns prior to training accomplishes an 80% reduction in network size as well as in training and test time. Cross-validation tests confirm accurate on-line flow regime identification.

Energy Technology Data Exchange (ETDEWEB)

The Plant Life Assessment Network (PLAN) is a Brite Euram Type II Thematic Network, initiated by the European Commission to facilitate structured co-operation between all cost shared action projects already funded by the Commission which fall under this common technical theme. The projects involved address a multiplicity of problems associated with plant life assessment and are drawn from Brite-Euram, Standards, Measurement and Testing, Nuclear Fission Safety and Esprit EC programmes. The main aim of the Network is to initiate, maintain and monitor a fruitful co-operation process between completed, ongoing and future EC R and D projects, thereby promoting improved cross fertilization and enhanced industrial exploitation of R and D results. As the project is in its infancy, this presentation covers the background to the initiative in some detail. In particular two key aspects are highlighted, namely, the requirement of the ...

Science.gov (United States)

A new study identifies and ranks the 10 security gaps responsible for most outsider attacks on college computer networks. The list is intended to help campus system administrators establish priorities as they work to increase security. One network security expert urges that institutions utilize multiple security layers. (DB)

Energy Technology Data Exchange (ETDEWEB)

Within this paper the potentialities of using networked embedded systems will be discussed. New embedded hardware with network connectivity allows remote administration and software updates of solar thermal system controllers via internet. System self analysis helps to minimize breakdown times by sending email and SMS to request maintenance staff. (orig.)

Energy Technology Data Exchange (ETDEWEB)

This paper describes a study of a security method of protecting inside network computers against outside miscreants and unwelcome visitors and a control method when these computers are connected with the Internet. In the present Internet, a method to encipher all data cannot be used, so that it is necessary to utilize PEM (Privacy Enhanced Mail) capable of the encipherment and conversion of secret information. For preventing miscreant access by eavesdropping password, one-time password is effective. The most cost-effective method is a firewall system. This system lies between the outside and inside network. By limiting computers that directly communicate with the Internet, control is centralized and inside network Security is protected. If the security of firewall systems is strictly controlled under correct setting, security within the network can be secured even in open networks ...

Energy Technology Data Exchange (ETDEWEB)

Knowledge is a success factor for globally acting company networks as a. o. the aim-oriented knowledge transfer between partners is an essential condition for a successful cooperation. Several network specific problems impede however an efficient and effective knowledge management; e.g. the transfer of competition relevant data is a high sensitive theme. The authors describe how a relevant method can be selected, adapted and implemented to the application-specific boundary conditions. They integrate existing attempts processes and methods to establish an effective knowledge development and an efficient knowledge transfer in the network and take into account ''hard'' (IT-technical-oriented solution approaches) as also ''soft'' factors (e.g. cultural and personal aspects). So the authors present unified instruments for an integrated knowledge management ...

British Library Electronic Table of Contents (United Kingdom)

Machine-to-machine (M2M) communications is a new and rapidly developing technology for large-scale networking of devices without dependence on human interaction. Energy efficiency is one of the important design objectives for machine-to-machine network architectures that often contain multi-hop wireless subnetworks. Constructing energy-efficient routes for sending data through such networks is important not only for the longevity of the nodes which typically depend on battery energy, but also for achieving an environmentally friendly system design overall, which will be imperative as M2M networks scale in number of nodes as projected. The objective of this survey is to provide a comprehensive look into shortest-path based energy-efficient routing alternatives to provide a reference for sys...

British Library Electronic Table of Contents (United Kingdom)

An anthropologist shares with the ?SNA and data mining community? his own anthropological perspective framed during more than five decades of network thinking about a broad range of anthropological problems. For 50?years he has viewed all people, things, and ideas in dynamic relationships. That perspective is a network perspective and at the same time anthropological, combining ethnographic, historical, holistic, and comparative views. It is valuable and beneficial to the community of scholars who use network analysis to try to understand what is going on, what went on before, and what the future prospects are. As an anthropologist, his interest is more in the wholes generated by network linkages?systems of households, bands, lineages, communities, corporations, governments?than in the ind...

Energy Technology Data Exchange (ETDEWEB)

This paper reports on a study to validate the Graphical Network Representation (GRPHREP) model which is being conducted on the Los Alamos National Laboratory Integrated Computer Network (ICN). The GRPHREP model is a software system application based on graph theory and object-oriented programming methodologies. It codified the Department of Energy (DOE) Order 5637.1, which is concerned with classified computer secret policy, restrictions, and requirements. The Los Alamos ICN is required to control access to and support large-scale scientific and administrative computing. Thus, large-scale scientific and administrative computing. Thus we felt that this large, complex, and dynamic network would provide a good test for the graphical and functional capabilities of the model. Furthermore, the ICN is composed of multiple partitions that reflect the sensitivity and classification of the computation (data) and designate the ...

International Nuclear Information System (INIS)

Nuclear knowledge is the basis for almost all nuclear activities, and education and training are the most fundamental means to transfer knowledge from one generation to the next. Understanding means and trends in knowledge transfer through education and training thus deserves a closer examination. In the past years, a number of trends and questions in nuclear knowledge, education and training have emerged. With declining student enrolment numbers and a general stagnation of the use of nuclear power in some of the IAEA's Member States, the issue of a slow erosion of the knowledge base and the possibility of loosing knowledge has become increasingly important, in particular if seen against the background of a possible renaissance of nuclear power in the future. In other Member States, an expansion of nuclear power is expected, with a corresponding need for human resources. As a result, in many Member States education and training of the next generation and succession planning have become ...

CERN Document Server

Two-tier networks, comprising a conventional cellular network overlaid with shorter range hotspots (e.g. femtocells, distributed antennas, or wired relays), offer an economically viable way to improve cellular system capacity. The capacity-limiting factor in such networks is interference. The cross-tier interference between macrocells and femtocells can suffocate the capacity due to the near-far problem, so in practice hotspots should use a different frequency channel than the potentially nearby high-power macrocell users. Centralized or coordinated frequency planning, which is difficult and inefficient even in conventional cellular networks, is all but impossible in a two-tier network. This paper proposes and analyzes an optimum decentralized spectrum allocation policy for two-tier networks that employ frequency division multiple access (including OFDMA). The ...

CERN Document Server

In Internet Routing, the static shortest path (SP) problem has been addressed using well known intelligent optimization techniques like artificial neural networks, genetic algorithms (GAs) and particle swarm optimization. Advancement in wireless communication lead more and more mobile wireless networks, such as mobile networks [mobile ad hoc networks (MANETs)] and wireless sensor networks. Dynamic nature of the network is the main characteristic of MANET. Therefore, the SP routing problem in MANET turns into dynamic optimization problem (DOP). Here the nodes ae made aware of the environmental condition, thereby making it intelligent, which goes as the input for GA. The implementation then uses GAs with immigrants and memory schemes to solve the dynamic SP routing problem (DSPRP) in MANETS. In our paper, once the network topology changes, the ...

Energy Technology Data Exchange (ETDEWEB)

ENEA (Italian National Agency for New Technologies, Energy and the Environment) is conducting a large research and development programme on innovative vehicles with high energy efficiency and low environmental impact. In particular conducts activities on electric and hybrid vehicles. Testing and evaluation activities play a strong role in this programme. A complete characterization chain has been then defined and set up with a network of facilities which covers main testing needs for single components, subsystems and complete vehicles, in simulated and real operating conditions. The test facility which has been realised is able to experiment and fully characterise complete drive-trains (and subsystems) for pure electric and hybrid vehicles. It is composed by a different section for each subsystem: 1) power generation; 2) energy storage and management; 3) driving motors. Each section acts as an experimental island, able to operate alone or ...

International Nuclear Information System (INIS)

The transmutation of minor actinides in-reactor is one solution currently being studied for the long time management of nuclear waste. In the heterogeneous concept the radionuclides are incorporating in an inert ceramic matrix. The support material must be insensitive to radiation damage. Fission product damage is the main radiation damage source during the transmutation process and therefore it is of the utmost importance to study their effects. We irradiated spinels MgAl_2O_4 (matrix of reference) and ZnAl_2O_4 by fast ions (by example: (86)Kr of approximately 400 MeV) simulating the fission products. Under these conditions, the damage is primarily due to the electronic energy losses (Se). One of the structural features of spinel AB_2O_4 is that the two cations (A(2+) and B(3+)) can exchange their site. This phenomenon is quantified by the inversion parameter. We highlight by XRD in grazing incidence that the structural changes observed in MgAl_2O_4 correspond to ...

Energy Technology Data Exchange (ETDEWEB)

The significant design features of a high-voltage dc (HVDC) circuit breaker based on the commutation concept were developed. Tests of components indicate the breaker is capable of interrupting a fault current of 10 kA on a 400 kV system and absorbing up to 10 MJ of system energy without generating more than 1.6 per unit (P.U.) voltage of the system. Interactions of the breaker with a three-terminal network were studied, using a system simulator. An ultrafast hydraulic actuator system was developed for this program which enables the breaker to initiate the current limiting process within 5 ms after receipt of a trip signal. A new hydraulic valve, operated by a repulsion coil, minimizes the delay before motion begins. Interruption will occur in series-connected vacuum interrupters. A 400 kV circuit breaker is estimated to require eight breaks in series. Only a single break was tested as part of this program because of the scale and cost required ...

KoreaScience (Korea)

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