Science.gov

Sample records for agent system solution

  1. A decontamination system for chemical weapons agents using a liquid solution on a solid sorbent.

    PubMed

    Waysbort, Daniel; McGarvey, David J; Creasy, William R; Morrissey, Kevin M; Hendrickson, David M; Durst, H Dupont

    2009-01-30

    A decontamination system for chemical warfare agents was developed and tested that combines a liquid decontamination reagent solution with solid sorbent particles. The components have fewer safety and environmental concerns than traditional chlorine bleach-based products or highly caustic solutions. The liquid solution, based on Decon Greentrade mark, has hydrogen peroxide and a carbonate buffer as active ingredients. The best solid sorbents were found to be a copolymer of ethylene glycol dimethacrylate and n-lauryl methacrylate (Polytrap 6603 Adsorber); or an allyl methacrylate cross-linked polymer (Poly-Pore E200 Adsorber). These solids are human and environmentally friendly and are commonly used in cosmetics. The decontaminant system was tested for reactivity with pinacolyl methylphosphonofluoridate (Soman, GD), bis(2-chloroethyl)sulfide (Mustard, HD), and S-(2-diisopropylaminoethyl) O-ethyl methylphosphonothioate (VX) by using NMR Spectroscopy. Molybdate ion (MoO(4)(-2)) was added to the decontaminant to catalyze the oxidation of HD. The molybdate ion provided a color change from pink to white when the oxidizing capacity of the system was exhausted. The decontaminant was effective for ratios of agent to decontaminant of up to 1:50 for VX (t(1/2) < or = 4 min), 1:10 for HD (t(1/2) < 2 min with molybdate), and 1:10 for GD (t(1/2) < 2 min). The vapor concentrations of GD above the dry sorbent and the sorbent with decontamination solution were measured to show that the sorbent decreased the vapor concentration of GD. The E200 sorbent had the additional advantage of absorbing aqueous decontamination solution without the addition of an organic co-solvent such as isopropanol, but the rate depended strongly on mixing for HD.

  2. Reductive destruction and decontamination of aqueous solutions of chlorinated antimicrobial agent using bimetallic systems.

    PubMed

    Ghauch, Antoine; Tuqan, Almuthanna

    2009-05-30

    Palladium, ruthenium and silver were investigated as catalysts for the dechlorination of dichlorophen (DCP, 2,2'-methylenebis(4-chlorophenol)), an antimicrobial and anthelmintic agent largely used as algicide, fungicide and bactericide. Experiments were undertaken under oxic and anoxic conditions for experimental durations up to 180 min (3h). The anoxic conditions were achieved by purging the solutions with nitrogen gas. Reactions were performed in a 12+/-0.5 mg L(-1) DCP solution (V=20 mL) using 0.8 g of Fe(0) (40 g L(-1)). Along with micrometric Fe(0), five Fe(0)-plated systems were investigated: Pd (1%), Ru (0.01%), Ru (0.1%), Ru (1%) and Ag (1%). Metal plating was controlled by atomic absorption spectroscopy. DCP degradation was monitored using: (i) two HPLC devices, (ii) ion chromatography, (iii) UV and fluorescence spectrophotometry. Results indicated: (i) total dechlorination with Fe/Pd, (ii) partial dechlorination (40%) with Fe/Ru, and no reaction with Fe/Ag. DCP is vanished completely after 90 min of contact with Fe/Pd following a first order kinetic. The observed degradation rate k(obs) was about (3.98+/-0.10)x10(-2)min(-1), the calculated half-life t(1/2) about 17.4+/-0.9 min and a t(50) about 10.1+/-0.5 min. A DCP degradation pathway map was also proposed.

  3. Model of Turbulent Flow of Rheological Solutions of Foaming Agents in Channels of Automatic Fire-Extinguishing Systems

    NASA Astrophysics Data System (ADS)

    Polevoda, I. I.; Karpenchuk, I. V.; Striganova, M. Yu.; Shatilo, É. É.

    2015-01-01

    A model of turbulent flow of a rheological solution of a foaming agent in a cylindrical channel of an automatic fire-extinguishing system is proposed; this model allows for the viscous stresses produced in the region of hydraulic roughness of the channel. Integral equations are obtained for calculation of the flow velocity and rate of flow of the foaming agent in the indicated channel, and also of the hydraulic resistance and head loss in it. Recommendations on practical use of the proposed theoretical model have been developed.

  4. On modeling of chemical stimulation of an enhanced geothermal system using a high pH solution with chelating agent

    SciTech Connect

    Xu, T.; Rose, P.; Fayer, S.; Pruess, K.

    2009-05-01

    Dissolution of silica and calcite in the presence of a chelating agent (NTA) at a high pH was successfully demonstrated in laboratory experiments using a high-temperature flow reactor. (Note that the term 'silica' used here includes amorphous silica, quartz, and silicate glass bead). The mineral dissolution and associated porosity enhancement in the experiments were reproduced by reactive transport modeling using TOUGHREACT. The chemical stimulation method was applied by numerical modeling to a field geothermal injection well system to investigate its effectiveness. Parameters applicable to the quartz monzodiorite unit at the Enhanced Geothermal Systems (EGS) site at Desert Peak (Nevada) were used. Results indicate that the injection of a high pH chelating solution results in dissolution of both calcite and plagioclase, while avoiding precipitation of calcite at high temperature conditions. Consequently reservoir porosity and permeability can be enhanced especially near the injection well. Injection at a lower temperature of 120 C (over 160 C in the base-case) results in a porosity increase that is smaller close to the injection point, but extends to a larger radial distance. A slower kinetic rate results in less aggressive mineral dissolution close to the injection point and larger extent along the flow path, which is favorable for chemical stimulation.

  5. Xenon fluoride solutions effective as fluorinating agents

    NASA Technical Reports Server (NTRS)

    Hyman, H. H.; Quarterman, L. A.; Sheft, I.

    1967-01-01

    Solutions of xenon fluorides in anhydrous hydrogen fluoride have few disruptive effects and leave a residue consisting of gaseous xenon, which can be recovered and refluorinated. This mild agent can be used with materials which normally must be fluorinated with fluorine alone at high temperatures.

  6. Proteinlike copolymers as encapsulating agents for small-molecule solutes.

    PubMed

    Malik, Ravish; Genzer, Jan; Hall, Carol K

    2015-03-24

    We describe the utilization of proteinlike copolymers (PLCs) as encapsulating agents for small-molecule solutes. We perform Monte Carlo simulations on systems containing PLCs and model solute molecules in order to understand how PLCs assemble in solution and what system conditions promote solute encapsulation. Specifically, we explore how the chemical composition of the PLCs and the range and strength of molecular interactions between hydrophobic segments on the PLC and solute molecules affect the solute encapsulation efficiency. The composition profiles of the hydrophobic and hydrophilic segments, the solute, and implicit solvent (or voids) within the PLC globule are evaluated to gain a complete understanding of the behavior in the PLC/solute system. We find that a single-chain PLC encapsulates solute successfully by collapsing the macromolecule to a well-defined globular conformation when the hydrophobic/solute interaction is at least as strong as the interaction strength among hydrophobic segments and the interaction among solute molecules is at most as strong as the hydrophobic/solute interaction strength. Our results can be used by experimentalists as a framework for optimizing unimolecular PLC solute encapsulation and can be extended potentially to applications such as "drug" delivery via PLCs.

  7. Solution of partial differential equations by agent-based simulation

    NASA Astrophysics Data System (ADS)

    Szilagyi, Miklos N.

    2014-01-01

    The purpose of this short note is to demonstrate that partial differential equations can be quickly solved by agent-based simulation with high accuracy. There is no need for the solution of large systems of algebraic equations. This method is especially useful for quick determination of potential distributions and demonstration purposes in teaching electromagnetism.

  8. Ecology Based Decentralized Agent Management System

    NASA Technical Reports Server (NTRS)

    Peysakhov, Maxim D.; Cicirello, Vincent A.; Regli, William C.

    2004-01-01

    The problem of maintaining a desired number of mobile agents on a network is not trivial, especially if we want a completely decentralized solution. Decentralized control makes a system more r e bust and less susceptible to partial failures. The problem is exacerbated on wireless ad hoc networks where host mobility can result in significant changes in the network size and topology. In this paper we propose an ecology-inspired approach to the management of the number of agents. The approach associates agents with living organisms and tasks with food. Agents procreate or die based on the abundance of uncompleted tasks (food). We performed a series of experiments investigating properties of such systems and analyzed their stability under various conditions. We concluded that the ecology based metaphor can be successfully applied to the management of agent populations on wireless ad hoc networks.

  9. Peculiarities of state diagrams of aqueous solutions of cryoprotective agents.

    PubMed

    Osetsky, Alexander I

    2009-10-01

    The phase transitions in aqueous solutions of glycerol and PEO-1500 within the temperature range of +30 to -150 degrees C have been studied using the methods of thermoplastic analysis and volumetric scanning tensodilatometry. We present the revealed phenomenon of cluster cyrystallization of these solutions as well as principles of describing this phenomenon using state diagrams, containing the intervals of concentration corresponding to the existence of amorphous and cryocolloid fractions. We note that for the cryocolloid fraction, a low temperature association of molecules of cryoprotective agents leads the formation of ice nanocrystals either close to or directly inside the aggregations. These fractions exist in cooled cryoprotective solutions near the vitrification temperatures of the liquid phase and may contribute to the initiation of damaging events in cryopreserved biological systems. Our data may be helpful in explaining the peculiarities observed during crystallization of cryoprotective solutions and may further contribute to a broader understanding of the principles of protection and protocol optimization of biological materials at temperatures approaching vitrification.

  10. Multi-agent autonomous system

    NASA Technical Reports Server (NTRS)

    Fink, Wolfgang (Inventor); Dohm, James (Inventor); Tarbell, Mark A. (Inventor)

    2010-01-01

    A multi-agent autonomous system for exploration of hazardous or inaccessible locations. The multi-agent autonomous system includes simple surface-based agents or craft controlled by an airborne tracking and command system. The airborne tracking and command system includes an instrument suite used to image an operational area and any craft deployed within the operational area. The image data is used to identify the craft, targets for exploration, and obstacles in the operational area. The tracking and command system determines paths for the surface-based craft using the identified targets and obstacles and commands the craft using simple movement commands to move through the operational area to the targets while avoiding the obstacles. Each craft includes its own instrument suite to collect information about the operational area that is transmitted back to the tracking and command system. The tracking and command system may be further coupled to a satellite system to provide additional image information about the operational area and provide operational and location commands to the tracking and command system.

  11. Stability of apomorphine in solutions containing selected antioxidant agents.

    PubMed

    Ang, Zen Yang; Boddy, Michael; Liu, Yandi; Sunderland, Bruce

    2016-01-01

    Apomorphine in solution undergoes rapid autoxidation, producing greenish colored solutions, making it difficult to formulate as a stable pharmaceutical solution. To identify the optimum antioxidant agent/combination for apomorphine solution, a high performance liquid chromatography assay was used to study the stability of 50 μg/mL apomorphine HCI in 0.1% L-ascorbic acid (AA), 0.1% sodium metabisulfite (SMB), 0.1% EDTA, and in selected combinations at 25°C, 32°C, and 37°C over a period of 14 days. The stability of apomorphine HCl (10 mg/mL) in 0.1% AA solution and in 0.1% EDTA solution at 25°C and 37°C was also evaluated. Apomorphine HCI solution (50 μg/mL) in 0.1% AA plus 0.1% SMB solution retained 99.7% (at 25°C) and 95.9% (at 37°C) of the initial concentration, as 0.1% AA plus SMB solution minimized the reactive oxygen content in solution which, in turn, reduced the oxidation rate of apomorphine HCl, and there was no green coloration perceptible. Conversely, apomorphine HCl solution (50 μg/mL) in 0.1% SMB solution was unstable as only 0.53% (at 25°C) and 0.06% (at 37°C) of the initial concentration was retained after 14 days. All 10 mg/mL apomorphine HCl samples were stable in both studies. The initial concentration of apomorphine HCl solution markedly affected its rate of oxidation and discoloration. The addition of 0.1% AA to a current formulation of apomorphine HCl injection (Apomine(®)), which contains SMB as an antioxidant, was recommended as providing the most stable solution.

  12. Stability of apomorphine in solutions containing selected antioxidant agents

    PubMed Central

    Ang, Zen Yang; Boddy, Michael; Liu, Yandi; Sunderland, Bruce

    2016-01-01

    Apomorphine in solution undergoes rapid autoxidation, producing greenish colored solutions, making it difficult to formulate as a stable pharmaceutical solution. To identify the optimum antioxidant agent/combination for apomorphine solution, a high performance liquid chromatography assay was used to study the stability of 50 μg/mL apomorphine HCI in 0.1% L-ascorbic acid (AA), 0.1% sodium metabisulfite (SMB), 0.1% EDTA, and in selected combinations at 25°C, 32°C, and 37°C over a period of 14 days. The stability of apomorphine HCl (10 mg/mL) in 0.1% AA solution and in 0.1% EDTA solution at 25°C and 37°C was also evaluated. Apomorphine HCI solution (50 μg/mL) in 0.1% AA plus 0.1% SMB solution retained 99.7% (at 25°C) and 95.9% (at 37°C) of the initial concentration, as 0.1% AA plus SMB solution minimized the reactive oxygen content in solution which, in turn, reduced the oxidation rate of apomorphine HCl, and there was no green coloration perceptible. Conversely, apomorphine HCl solution (50 μg/mL) in 0.1% SMB solution was unstable as only 0.53% (at 25°C) and 0.06% (at 37°C) of the initial concentration was retained after 14 days. All 10 mg/mL apomorphine HCl samples were stable in both studies. The initial concentration of apomorphine HCl solution markedly affected its rate of oxidation and discoloration. The addition of 0.1% AA to a current formulation of apomorphine HCl injection (Apomine®), which contains SMB as an antioxidant, was recommended as providing the most stable solution. PMID:27757015

  13. Solution of Nonlinear Systems

    NASA Technical Reports Server (NTRS)

    Turner, L. R.

    1960-01-01

    The problem of solving systems of nonlinear equations has been relatively neglected in the mathematical literature, especially in the textbooks, in comparison to the corresponding linear problem. Moreover, treatments that have an appearance of generality fail to discuss the nature of the solutions and the possible pitfalls of the methods suggested. Probably it is unrealistic to expect that a unified and comprehensive treatment of the subject will evolve, owing to the great variety of situations possible, especially in the applied field where some requirement of human or mechanical efficiency is always present. Therefore we attempt here simply to pose the problem and to describe and partially appraise the methods of solution currently in favor.

  14. Tumor resistance to vascular disrupting agents: mechanisms, imaging, and solutions

    PubMed Central

    Liang, Wenjie; Ni, Yicheng; Chen, Feng

    2016-01-01

    The emergence of vascular disrupting agents (VDAs) is a significant advance in the treatment of solid tumors. VDAs induce rapid and selective shutdown of tumor blood flow resulting in massive necrosis. However, a viable marginal tumor rim always remains after VDA treatment and is a major cause of recurrence. In this review, we discuss the mechanisms involved in the resistance of solid tumors to VDAs. Hypoxia, tumor-associated macrophages, and bone marrow-derived circulating endothelial progenitor cells all may contribute to resistance. Resistance can be monitored using magnetic resonance imaging markers. The various solutions proposed to manage tumor resistance to VDAs emphasize combining these agents with other approaches including antiangiogenic agents, chemotherapy, radiotherapy, radioimmunotherapy, and sequential dual-targeting internal radiotherapy. PMID:26812886

  15. Sensory properties of ginseng solutions modified by masking agents.

    PubMed

    Tamamoto, Lauren C; Schmidt, Shelly J; Lee, Soo-Yeun

    2010-09-01

    Ginseng is one of the most popular functional ingredients found in energy drink formulations. Although ginseng is known for its health benefits, ginseng is also notorious for imparting a bitter taste. Incorporating ginseng into beverages without the bitterness, while still maintaining its health benefits, is necessary for developing an acceptable product. Thus, the objectives of this study were to (1) identify effective treatments for minimizing the bitterness of ginseng in water base and model energy drink base solutions and (2) determine the sensory effects of incorporating different treatment levels to minimize the bitterness of ginseng. A series of pilot studies investigating bitterness reducing treatments were conducted, which included: congruent flavor addition, bitterness blocking agent incorporation, enzymatic modification, ingredient interaction, and complexation. Based on the results of a series of pilot studies, γ-cyclodextrin (γ-CD) and β-cyclodextrin (β-CD) complexation agents were identified as having the most potential. Effectiveness of the γ-CDs, β-CDs, and combinations of γ- and β-CDs were tested in 100 mL water and in 100 mL model energy drink base solutions containing 0.052 g 80% ginsenosides panax ginseng, using descriptive sensory analysis. Twelve trained panelists evaluated 42 solution treatments (3 treatments × 7 levels × 2 bases) for bitter attributes with and without nose clips. Overall, the most effective treatments were 0.09 g γ-CDs in 100 mL of solution and 1 g β-CDs in 100 mL solution, which both reduced the bitterness intensity of the solutions by half. Incorporation of these levels of CDs in water and model energy drink base solutions containing ginseng will aid in the development of functional beverages that are more acceptable to a wider range of consumers.

  16. Biologic agents in systemic vasculitis

    PubMed Central

    Henderson, Charles F; Seo, Philip

    2012-01-01

    The treatment of systemic necrotizing vasculitis has made great strides in both efficacy and outcomes. Standard therapies, however, are associated with numerous side effects, and not all patients will respond to conventional immunosuppression. These realities have prompted the search for safer and more efficacious treatments, most notably among biologic agents. For example, the role of TNF-α in the pathophysiology of several vasculitides has led to the investigation of targeted inhibitors of this cytokine, albeit with mixed results. There have been some disappointing results in the area of giant cell arteritis and Wegener’s granulomatosis (granulomatosis with polygiitis), but anti-TNF therapy has shown promise in the treatment of Takayasu’s arteritis, although additional trials to demonstrate its efficacy are required. Anti-B-cell therapy seems to be the most promising advance in the management of these diseases. Complete and partial responses have been seen in both primary and secondary mixed cryoglobulinemic vasculitis. Recent trials have demonstrated that rituximab is effective for the treatment of Wegener’s granulomatosis and microscopic polyangiitis. These trials have, however, raised concerns regarding the long-term safety of these agents. The future holds promise for additional targeted therapies with improved patient response and fewer side effects. PMID:23785387

  17. Inactivation of biological agents using neutral oxone-chloride solutions.

    PubMed

    Delcomyn, Carrie A; Bushway, Karen E; Henley, Michael V

    2006-04-15

    Bleach solutions containing the active ingredient hypochlorite (OCl-) serve as powerful biological disinfectants but are highly caustic and present a significant compatibility issue when applied to contaminated equipment or terrain. A neutral, bicarbonate-buffered aqueous solution of Oxone (2K2HSO5.KHSO4.K2SO4) and sodium chloride that rapidly generates hypochlorite and hypochlorous acid (HOCl) in situ was evaluated as a new alternative to bleach for the inactivation of biological agents. The solution produced a free chlorine (HOCl + OCl-) concentration of 3.3 g/L and achieved > or =5.8-log inactivation of spores of Bacillus atrophaeus, Bacillus thuringiensis, Aspergillus niger, and Escherichia coli vegetative cells in 1 min at 22 degrees C. Seawaterwas an effective substitute for solid sodium chloride and inactivated 5 to 8 logs of each organism in 10 min over temperatures ranging from -5 degrees C to 55 degrees C. Sporicidal effectiveness increased as free chlorine concentrations shifted from OCl- to HOCl. Neutrally buffered Oxone-chloride and Oxone-seawater solutions are mitigation alternatives for biologically contaminated equipment and environments that would otherwise be decontaminated using caustic bleach solutions.

  18. Massive Multi-Agent Systems Control

    NASA Technical Reports Server (NTRS)

    Campagne, Jean-Charles; Gardon, Alain; Collomb, Etienne; Nishida, Toyoaki

    2004-01-01

    In order to build massive multi-agent systems, considered as complex and dynamic systems, one needs a method to analyze and control the system. We suggest an approach using morphology to represent and control the state of large organizations composed of a great number of light software agents. Morphology is understood as representing the state of the multi-agent system as shapes in an abstract geometrical space, this notion is close to the notion of phase space in physics.

  19. Multi-agent for manufacturing systems optimization

    NASA Astrophysics Data System (ADS)

    Ciortea, E. M.; Tulbure, A.; Huţanu, C.-tin

    2016-08-01

    The paper is meant to be a dynamic approach to optimize manufacturing systems based on multi-agent systems. Multi-agent systems are semiautonomous decision makers and cooperate to optimize the manufacturing process. Increasing production the capacity is achieved by developing, implementing efficient and effective systems from control based on current manufacturing process. The model multi-agent proposed in this paper is based on communication between agents who, based on their mechanisms drive to autonomous decision making. Methods based on multi-agent programming are applied between flexible manufacturing processes and cooperation with agents. Based on multi-agent technology and architecture of intelligent manufacturing can lead to development of strategies for control and optimization of scheduled production resulting from the simulation.

  20. Differential effect of buffering agents on the crystallization of gemcitabine hydrochloride in frozen solutions.

    PubMed

    Patel, Mehulkumar; Munjal, Bhushan; Bansal, Arvind K

    2014-08-25

    The purpose of this study was to evaluate the differential effect of buffering agents on the crystallization of gemcitabine hydrochloride (GHCl) in frozen solutions. Four buffering agents, viz. citric acid (CA), malic acid (MA), succinic acid (SA) and tartaric acid (TA) were selected and their effect on GHCl crystallization was monitored using standard DSC and low temperature XRD. Onset of GHCl crystallization during heating run in DSC was measured to compare the differential effect of buffering agents. Glass transition temperature (Tg'), unfrozen water content in the freeze concentrate and crystallization propensity of the buffering agents was also determined for mechanistic understanding of the underlying effects. CA and MA inhibited while SA facilitated crystallization of GHCl even at 25 mM concentration. Increasing the concentration enhanced their effect. However, TA inhibited GHCl crystallization at concentrations <100mM and facilitated it at concentrations ≥100 mM. Lyophilization of GHCl with either SA or TA yielded elegant cakes, while CA and MA caused collapse. Tg' failed to explain the inhibitory effects of CA, MA and TA as all buffering agents lowered the Tg' of the system. Differential effect of buffering agents on GHCl crystallization could be explained by consideration of two opposing factors: (i) their own crystallization tendency and (ii) unfrozen water content in the freeze concentrate. In conclusion, it was established that API crystallization in frozen solution is affected by the type and concentration of the buffering agents. Copyright © 2014 Elsevier B.V. All rights reserved.

  1. Anchor Toolkit - a secure mobile agent system

    SciTech Connect

    Mudumbai, Srilekha S.; Johnston, William; Essiari, Abdelilah

    1999-05-19

    Mobile agent technology facilitates intelligent operation insoftware systems with less human interaction. Major challenge todeployment of mobile agents include secure transmission of agents andpreventing unauthorized access to resources between interacting systems,as either hosts, or agents, or both can act maliciously. The Anchortoolkit, designed by LBNL, handles the transmission and secure managementof mobile agents in a heterogeneous distributed computing environment. Itprovides users with the option of incorporating their security managers.This paper concentrates on the architecture, features, access control anddeployment of Anchor toolkit. Application of this toolkit in a securedistributed CVS environment is discussed as a case study.

  2. Evolutionary algorithms and multi-agent systems

    NASA Astrophysics Data System (ADS)

    Oh, Jae C.

    2006-05-01

    This paper discusses how evolutionary algorithms are related to multi-agent systems and the possibility of military applications using the two disciplines. In particular, we present a game theoretic model for multi-agent resource distribution and allocation where agents in the environment must help each other to survive. Each agent maintains a set of variables representing actual friendship and perceived friendship. The model directly addresses problems in reputation management schemes in multi-agent systems and Peer-to-Peer distributed systems. We present algorithms based on evolutionary game process for maintaining the friendship values as well as a utility equation used in each agent's decision making. For an application problem, we adapted our formal model to the military coalition support problem in peace-keeping missions. Simulation results show that efficient resource allocation and sharing with minimum communication cost is achieved without centralized control.

  3. Whole body postmortem angiography with a high viscosity contrast agent solution using poly ethylene glycol as contrast agent dissolver.

    PubMed

    Jackowski, Christian; Persson, Anders; Thali, Michael J

    2008-03-01

    Postmortem minimal invasive angiography has already been implemented to support virtual autopsy examinations. An experimental approach in a porcine model to overcome an initially described artificial tissue edema artifact by using a poly ethylene glycol (PEG) containing contrast agent solution showed promising results. The present publication describes the first application of PEG in a whole corpse angiographic CT examination. A minimal invasive postmortem CT angiography was performed in a human corpse utilizing the high viscosity contrast agent solution containing 65% of PEG. Injection was carried out via the femoral artery into the aortic root in simulated cardiac output conditions. Subsequent CT scanning delivered the 3D volume data of the whole corpse. Visualization of the human arterial anatomy was excellent and the contrast agent distribution was generally limited to the arterial system as intended. As exceptions an enhancement of the brain, the left ventricular myocardium and the renal cortex became obvious. This most likely represented the stage of centralization of the blood circulation at the time of death with dilatation of the precapillary arterioles within these tissues. Especially for the brain this resulted in a distinctively improved visualization of the intracerebral structures by CT. However, the general tissue edema artifact of postmortem minimal invasive angiography examinations could be distinctively reduced.

  4. Assurance in Agent-Based Systems

    SciTech Connect

    Gilliom, Laura R.; Goldsmith, Steven Y.

    1999-05-10

    Our vision of the future of information systems is one that includes engineered collectives of software agents which are situated in an environment over years and which increasingly improve the performance of the overall system of which they are a part. At a minimum, the movement of agent and multi-agent technology into National Security applications, including their use in information assurance, is apparent today. The use of deliberative, autonomous agents in high-consequence/high-security applications will require a commensurate level of protection and confidence in the predictability of system-level behavior. At Sandia National Laboratories, we have defined and are addressing a research agenda that integrates the surety (safety, security, and reliability) into agent-based systems at a deep level. Surety is addressed at multiple levels: The integrity of individual agents must be protected by addressing potential failure modes and vulnerabilities to malevolent threats. Providing for the surety of the collective requires attention to communications surety issues and mechanisms for identifying and working with trusted collaborators. At the highest level, using agent-based collectives within a large-scale distributed system requires the development of principled design methods to deliver the desired emergent performance or surety characteristics. This position paper will outline the research directions underway at Sandia, will discuss relevant work being performed elsewhere, and will report progress to date toward assurance in agent-based systems.

  5. Exchanging large data object in multi-agent systems

    NASA Astrophysics Data System (ADS)

    Al-Yaseen, Wathiq Laftah; Othman, Zulaiha Ali; Nazri, Mohd Zakree Ahmad

    2016-08-01

    One of the Business Intelligent solutions that is currently in use is the Multi-Agent System (MAS). Communication is one of the most important elements in MAS, especially for exchanging large low level data between distributed agents (physically). The Agent Communication Language in JADE has been offered as a secure method for sending data, whereby the data is defined as an object. However, the object cannot be used to send data to another agent in a different location. Therefore, the aim of this paper was to propose a method for the exchange of large low level data as an object by creating a proxy agent known as a Delivery Agent, which temporarily imitates the Receiver Agent. The results showed that the proposed method is able to send large-sized data. The experiments were conducted using 16 datasets ranging from 100,000 to 7 million instances. However, for the proposed method, the RAM and the CPU machine had to be slightly increased for the Receiver Agent, but the latency time was not significantly different compared to the use of the Java Socket method (non-agent and less secure). With such results, it was concluded that the proposed method can be used to securely send large data between agents.

  6. The Refinement of Multi-Agent Systems

    NASA Astrophysics Data System (ADS)

    Aştefănoaei, L.; de Boer, F. S.

    This chapter introduces an encompassing theory of refinement which supports a top-down methodology for designing multi-agent systems. We present a general modelling framework where we identify different abstraction levels of BDI agents. On the one hand, at a higher level of abstraction we introduce the language BUnity as a way to specify “what” an agent can do. On the other hand, at a more concrete layer we introduce the language BUpL as implementing not only what an agent can do but also “when” the agent can do. At this stage of individual agent design, refinement is understood as trace inclusion. Having the traces of an implementation included in the traces of a given specification means that the implementation is correct with respect to the specification.

  7. Analysis of decontamination solutions of G agents to detect reformation of agent. Final report, December 1991-March 1992

    SciTech Connect

    Beaudry, W.T.; Buchanan, J.H.; Rohrbaugh, D.K.; Samuel, J.B.; Szafraniec, L.L.

    1993-01-01

    Agents from a full scale binary munition test were decontaminated with caustic in a 300 gal holding tank. Analysis of the contents by standard methods revealed a trace amount of G agent present despite the highly caustic solution. A technical review of the analytical methods was carried out to determine if the G agent was actually present or an artifact of the analysis. A literature search revealed similar concerns when brine solutions from nerve agent decontamination were analyzed using similar analytical methods. This study concluded that nerve agents reformed at reduced PH or in chloroform extracts of the neutralized or slightly acidic brines. Experiments using nuclear magnetic resonance (NMR), gas chromatography (GC), and GC/mass spectrometry (GC/MS) were used to see where, if any, G agent was present during the analysis. Results obtained confirmed G agent reforming in either the neutral aqueous solution or in the chloroform extract but not in chloroform extracts of the caustic solution. No agent was detected using methylene chloride as the extraction solvent as recommended by the earlier study.

  8. Multi-Agent System for Resource Reliability

    DTIC Science & Technology

    2007-11-02

    1 research and development of a prototype for network resource reliability has laid the groundwork for the Phase 2 implementation of MASRR, a Multi - Agent System for Resource Reliability, and its eventual commercialization.

  9. Personalized E- learning System Based on Intelligent Agent

    NASA Astrophysics Data System (ADS)

    Duo, Sun; Ying, Zhou Cai

    Lack of personalized learning is the key shortcoming of traditional e-Learning system. This paper analyzes the personal characters in e-Learning activity. In order to meet the personalized e-learning, a personalized e-learning system based on intelligent agent was proposed and realized in the paper. The structure of system, work process, the design of intelligent agent and the realization of intelligent agent were introduced in the paper. After the test use of the system by certain network school, we found that the system could improve the learner's initiative participation, which can provide learners with personalized knowledge service. Thus, we thought it might be a practical solution to realize self- learning and self-promotion in the lifelong education age.

  10. A user-system interface agent

    NASA Technical Reports Server (NTRS)

    Wakim, Nagi T.; Srivastava, Sadanand; Bousaidi, Mehdi; Goh, Gin-Hua

    1995-01-01

    Agent-based technologies answer to several challenges posed by additional information processing requirements in today's computing environments. In particular, (1) users desire interaction with computing devices in a mode which is similar to that used between people, (2) the efficiency and successful completion of information processing tasks often require a high-level of expertise in complex and multiple domains, (3) information processing tasks often require handling of large volumes of data and, therefore, continuous and endless processing activities. The concept of an agent is an attempt to address these new challenges by introducing information processing environments in which (1) users can communicate with a system in a natural way, (2) an agent is a specialist and a self-learner and, therefore, it qualifies to be trusted to perform tasks independent of the human user, and (3) an agent is an entity that is continuously active performing tasks that are either delegated to it or self-imposed. The work described in this paper focuses on the development of an interface agent for users of a complex information processing environment (IPE). This activity is part of an on-going effort to build a model for developing agent-based information systems. Such systems will be highly applicable to environments which require a high degree of automation, such as, flight control operations and/or processing of large volumes of data in complex domains, such as the EOSDIS environment and other multidisciplinary, scientific data systems. The concept of an agent as an information processing entity is fully described with emphasis on characteristics of special interest to the User-System Interface Agent (USIA). Issues such as agent 'existence' and 'qualification' are discussed in this paper. Based on a definition of an agent and its main characteristics, we propose an architecture for the development of interface agents for users of an IPE that is agent-oriented and whose resources

  11. A Multiagent Recommender System with Task-Based Agent Specialization

    NASA Astrophysics Data System (ADS)

    Lorenzi, Fabiana; Correa, Fabio Arreguy Camargo; Bazzan, Ana L. C.; Abel, Mara; Ricci, Francesco

    This paper describes a multiagent recommender system where agents maintain local knowledge bases and, when requested to support a travel planning task, they collaborate exchanging information stored in their local bases. A request for a travel recommendation is decomposed by the system into sub tasks, corresponding to travel services. Agents select tasks autonomously, and accomplish them with the help of the knowledge derived from previous solutions. In the proposed architecture, agents become experts in some task types, and this makes the recommendation generation more efficient. In this paper, we validate the model via simulations where agents collaborate to recommend a travel package to the user. The experiments show that specialization is useful hence providing a validation of the proposed model.

  12. Bringing comfort to the masses: a novel evaluation of comfort agent solution properties.

    PubMed

    White, Charles J; Thomas, Calvin R; Byrne, Mark E

    2014-04-01

    Ocular comfort agents are molecules that relieve ocular discomfort by augmenting characteristics of the tear film to stabilize and retain tear volume and lubricate the ocular surface. While a number of clinical comparisons between ocular comfort agent solutions are available, very little work has been done correlating the properties of specific comfort agents (species, molecular weight, and water retention) and solution properties (concentration, viscosity, zero shear viscosity, and surface tension) to the performance and effectiveness of comfort agent solutions. In this work, comfort-promoting properties related strongly to comfort agent concentration and molecular weight, the first objective demonstration of this relationship across diverse comfort agent species and molecular weights. The comfort agents with the greatest comfort property contributions (independent of specific molecular weight and concentration considerations) were hyaluronic acid (HA), hydroxypropyl methylcellulose (HPMC), and carboxymethylcellulose (CMC), respectively. The observed, empirical relationships between comfort property contribution and comfort agent species, solution properties, comfort agent molecular weight, and solution concentration was used to develop novel comfort agent index values. The comfort agent index values provided much insight and understanding into the results of experimental studies and/or clinical trials and offer potential resolution to numerous conflicting reports within the literature by accounting for the difference in comfort agent performance due to molecular weight and concentration of comfort agents. The index values provide the first objective, experimental validation and explanation of numerous general trends suggested by clinical data. Copyright © 2013 British Contact Lens Association. Published by Elsevier Ltd. All rights reserved.

  13. FIPA agent based network distributed control system

    SciTech Connect

    D. Abbott; V. Gyurjyan; G. Heyes; E. Jastrzembski; C. Timmer; E. Wolin

    2003-03-01

    A control system with the capabilities to combine heterogeneous control systems or processes into a uniform homogeneous environment is discussed. This dynamically extensible system is an example of the software system at the agent level of abstraction. This level of abstraction considers agents as atomic entities that communicate to implement the functionality of the control system. Agents' engineering aspects are addressed by adopting the domain independent software standard, formulated by FIPA. Jade core Java classes are used as a FIPA specification implementation. A special, lightweight, XML RDFS based, control oriented, ontology markup language is developed to standardize the description of the arbitrary control system data processor. Control processes, described in this language, are integrated into the global system at runtime, without actual programming. Fault tolerance and recovery issues are also addressed.

  14. Multi Agent Systems with Symbiotic Learning and Evolution using GNP

    NASA Astrophysics Data System (ADS)

    Eguchi, Toru; Hirasawa, Kotaro; Hu, Jinglu; Murata, Junichi

    Recently, various attempts relevant to Multi Agent Systems (MAS) which is one of the most promising systems based on Distributed Artificial Intelligence have been studied to control large and complicated systems efficiently. In these trends of MAS, Multi Agent Systems with Symbiotic Learning and Evolution named Masbiole has been proposed. In Masbiole, symbiotic phenomena among creatures are considered in the process of learning and evolution of MAS. So we can expect more flexible and sophisticated solutions than conventional MAS. In this paper, we apply Masbiole to Iterative Prisoner’s Dilemma Games (IPD Games) using Genetic Network Programming (GNP) which is a newly developed evolutionary computation method for constituting agents. Some characteristics of Masbiole using GNP in IPD Games are clarified.

  15. Aqueous thiocyanate-urea solution as a powerful non-alkaline swelling agent for cellulose fibres.

    PubMed

    Mahmud-Ali, Amalid; Bechtold, Thomas

    2015-02-13

    For many applications cellulose fibres are treated with concentrated solutions of swelling agents to increase reactivity and to achieve reorganisation of fibre structure. Representative examples are caustic soda, potassium hydroxide solution or liquid ammonia. These highly concentrated media bear considerable safety hazards during the technical handling thus alternative swelling agents are of interest. The thiocyanate-urea system investigated in this work offers high swelling potential for regenerated cellulose fibres. Experiments with different cations of M(+) in M(+) SCN(-) demonstrate the significant influence of the cation on the degree of fibre swelling. In concentrated NaSCN/urea solutions, at 80 °C, lyocell fibres expand the diameter from 12-14 to 100 μm. The treatment in the swelling agent also led to a significant increase in the water retention value which was accompanied by a strength loss of 20-40% of the initial value. FTIR analysis of treated fibres did not indicate substantial changes in structure of the cellulose polymer. Limited weight loss of up to 20% was observed despite the high expansion of the fibre.

  16. [Systemic and neurological uses of immunosuppressive agents].

    PubMed

    Schnider, C; Seebach, J D; Ribi, C; Spertini, F

    2013-05-01

    Involvement of the central or peripheral nervous system, frequently present in systemic inflammatory immune disorders, has to be considered a severe threat and requires aggressive immunosuppressive treatment to achieve rapid remission. This is usually obtained with high-dose systemic corticosteroids combined with cyclophosphamide. Once remission is obtained, immunosuppressive agents with a more favorable safety profile are needed to exert a corticosteroid-sparing effect and minimize adverse events. New therapeutic approaches are currently developed to treat autoimmune diseases, mostly linked to the definition of new indications for biological agents such as TNF-alpha antagonists and rituximab.

  17. Multi-Agent Systems Design for Novices

    ERIC Educational Resources Information Center

    Lynch, Simon; Rajendran, Keerthi

    2005-01-01

    Advanced approaches to the construction of software systems can present difficulties to learners. This is true for multi-agent systems (MAS) which exhibit concurrency, non-determinacy of structure and composition and sometimes emergent behavior characteristics. Additional barriers exist for learners because mainstream MAS technology is young and…

  18. Multi-Agent Systems Design for Novices

    ERIC Educational Resources Information Center

    Lynch, Simon; Rajendran, Keerthi

    2005-01-01

    Advanced approaches to the construction of software systems can present difficulties to learners. This is true for multi-agent systems (MAS) which exhibit concurrency, non-determinacy of structure and composition and sometimes emergent behavior characteristics. Additional barriers exist for learners because mainstream MAS technology is young and…

  19. Bipartite flocking for multi-agent systems

    NASA Astrophysics Data System (ADS)

    Fan, Ming-Can; Zhang, Hai-Tao; Wang, Miaomiao

    2014-09-01

    This paper addresses the bipartite flock control problem where a multi-agent system splits into two clusters upon internal or external excitations. Using structurally balanced signed graph theory, LaSalle's invariance principle and Barbalat's Lemma, we prove that the proposed algorithm guarantees a bipartite flocking behavior. In each of the two disjoint clusters, all individuals move with the same direction. Meanwhile, every pair of agents in different clusters moves with opposite directions. Moreover, all agents in the two separated clusters approach a common velocity magnitude, and collision avoidance among all agents is ensured as well. Finally, the proposed bipartite flock control method is examined by numerical simulations. The bipartite flocking motion addressed by this paper has its references in both natural collective motions and human group behaviors such as predator-prey and panic escaping scenarios.

  20. Intelligent Complex Evolutionary Agent-Based Systems

    NASA Astrophysics Data System (ADS)

    Iantovics, Barna; Enǎchescu, Cǎlin

    2009-04-01

    In this paper, we investigate the possibility to develop intelligent agent-based complex systems that use evolutionary learning techniques in order to adapt for the efficient solving of the problems by reorganizing their structure. For this investigation is proposed a complex multiagent system called EAMS (Evolutionary Adaptive Multiagent System), which using an evolutionary learning technique can learn different patterns of reorganization. The realized study proves that evolutionary techniques successfully can be used to create complex multiagent systems capable to intelligently reorganize their structure during their life cycle. The practical establishment of the intelligence of a computational system in generally, an agent-based system in particularly consists in how efficiently and flexibly the system can solve difficult problems.

  1. Space/ground systems as cooperating agents

    NASA Technical Reports Server (NTRS)

    Grant, T. J.

    1994-01-01

    Within NASA and the European Space Agency (ESA) it is agreed that autonomy is an important goal for the design of future spacecraft and that this requires on-board artificial intelligence. NASA emphasizes deep space and planetary rover missions, while ESA considers on-board autonomy as an enabling technology for missions that must cope with imperfect communications. ESA's attention is on the space/ground system. A major issue is the optimal distribution of intelligent functions within the space/ground system. This paper describes the multi-agent architecture for space/ground systems (MAASGS) which would enable this issue to be investigated. A MAASGS agent may model a complete spacecraft, a spacecraft subsystem or payload, a ground segment, a spacecraft control system, a human operator, or an environment. The MAASGS architecture has evolved through a series of prototypes. The paper recommends that the MAASGS architecture should be implemented in the operational Dutch Utilization Center.

  2. 46 CFR 193.15-50 - Clean agent systems.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 7 2014-10-01 2014-10-01 false Clean agent systems. 193.15-50 Section 193.15-50... PROTECTION EQUIPMENT Carbon Dioxide and Clean Agent Extinguishing Systems, Details § 193.15-50 Clean agent systems. A clean agent system complying with 46 CFR subpart 95.16 may be used as an alternative to...

  3. 46 CFR 193.15-50 - Clean agent systems.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 7 2012-10-01 2012-10-01 false Clean agent systems. 193.15-50 Section 193.15-50... PROTECTION EQUIPMENT Carbon Dioxide and Clean Agent Extinguishing Systems, Details § 193.15-50 Clean agent systems. A clean agent system complying with 46 CFR subpart 95.16 may be used as an alternative to...

  4. 46 CFR 193.15-50 - Clean agent systems.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 7 2013-10-01 2013-10-01 false Clean agent systems. 193.15-50 Section 193.15-50... PROTECTION EQUIPMENT Carbon Dioxide and Clean Agent Extinguishing Systems, Details § 193.15-50 Clean agent systems. A clean agent system complying with 46 CFR subpart 95.16 may be used as an alternative to...

  5. Agent-Based Modeling in Systems Pharmacology.

    PubMed

    Cosgrove, J; Butler, J; Alden, K; Read, M; Kumar, V; Cucurull-Sanchez, L; Timmis, J; Coles, M

    2015-11-01

    Modeling and simulation (M&S) techniques provide a platform for knowledge integration and hypothesis testing to gain insights into biological systems that would not be possible a priori. Agent-based modeling (ABM) is an M&S technique that focuses on describing individual components rather than homogenous populations. This tutorial introduces ABM to systems pharmacologists, using relevant case studies to highlight how ABM-specific strengths have yielded success in the area of preclinical mechanistic modeling.

  6. Autonomous Formations of Multi-Agent Systems

    NASA Technical Reports Server (NTRS)

    Dhali, Sanjana; Joshi, Suresh M.

    2013-01-01

    Autonomous formation control of multi-agent dynamic systems has a number of applications that include ground-based and aerial robots and satellite formations. For air vehicles, formation flight ("flocking") has the potential to significantly increase airspace utilization as well as fuel efficiency. This presentation addresses two main problems in multi-agent formations: optimal role assignment to minimize the total cost (e.g., combined distance traveled by all agents); and maintaining formation geometry during flock motion. The Kuhn-Munkres ("Hungarian") algorithm is used for optimal assignment, and consensus-based leader-follower type control architecture is used to maintain formation shape despite the leader s independent movements. The methods are demonstrated by animated simulations.

  7. Autonomous Formations of Multi-Agent Systems

    NASA Technical Reports Server (NTRS)

    Dhali, Sanjana; Joshi, Suresh M.

    2013-01-01

    Autonomous formation control of multi-agent dynamic systems has a number of applications that include ground-based and aerial robots and satellite formations. For air vehicles, formation flight ("flocking") has the potential to significantly increase airspace utilization as well as fuel efficiency. This presentation addresses two main problems in multi-agent formations: optimal role assignment to minimize the total cost (e.g., combined distance traveled by all agents); and maintaining formation geometry during flock motion. The Kuhn-Munkres ("Hungarian") algorithm is used for optimal assignment, and consensus-based leader-follower type control architecture is used to maintain formation shape despite the leader s independent movements. The methods are demonstrated by animated simulations.

  8. Optimal flushing agents for integrated optical and acoustic imaging systems

    NASA Astrophysics Data System (ADS)

    Li, Jiawen; Minami, Hataka; Steward, Earl; Ma, Teng; Mohar, Dilbahar; Robertson, Claire; Shung, Kirk; Zhou, Qifa; Patel, Pranav; Chen, Zhongping

    2015-05-01

    An increasing number of integrated optical and acoustic intravascular imaging systems have been developed and hold great promise for accurately diagnosing vulnerable plaques and guiding atherosclerosis treatment. However, in any intravascular environment, the vascular lumen is filled with blood, a high-scattering source for optical and high-frequency ultrasound signals. Blood must be flushed away to provide clearer images. To our knowledge, no research has been performed to find the ideal flushing agent for combined optical and acoustic imaging techniques. We selected three solutions as potential flushing agents for their image-enhancing effects: mannitol, dextran, and iohexol. Testing of these flushing agents was performed in a closed-loop circulation model and in vivo on rabbits. We found that a high concentration of dextran was the most useful for simultaneous intravascular ultrasound and optical coherence tomography imaging.

  9. Optimal flushing agents for integrated optical and acoustic imaging systems.

    PubMed

    Li, Jiawen; Minami, Hataka; Steward, Earl; Ma, Teng; Mohar, Dilbahar; Robertson, Claire; Shung, Kirk; Zhou, Qifa; Patel, Pranav; Chen, Zhongping

    2015-05-01

    An increasing number of integrated optical and acoustic intravascular imaging systems have been developed and hold great promise for accurately diagnosing vulnerable plaques and guiding atherosclerosis treatment. However, in any intravascular environment, the vascular lumen is filled with blood, a high-scattering source for optical and high-frequency ultrasound signals. Blood must be flushed away to provide clearer images. To our knowledge, no research has been performed to find the ideal flushing agent for combined optical and acoustic imaging techniques. We selected three solutions as potential flushing agents for their image-enhancing effects: mannitol, dextran, and iohexol. Testing of these flushing agents was performed in a closed-loop circulation model and in vivo on rabbits. We found that a high concentration of dextran was the most useful for simultaneous intravascular ultrasound and optical coherence tomography imaging.

  10. Optimal flushing agents for integrated optical and acoustic imaging systems

    PubMed Central

    Li, Jiawen; Minami, Hataka; Steward, Earl; Ma, Teng; Mohar, Dilbahar; Robertson, Claire; Shung, Kirk; Zhou, Qifa; Patel, Pranav; Chen, Zhongping

    2015-01-01

    Abstract. An increasing number of integrated optical and acoustic intravascular imaging systems have been developed and hold great promise for accurately diagnosing vulnerable plaques and guiding atherosclerosis treatment. However, in any intravascular environment, the vascular lumen is filled with blood, a high-scattering source for optical and high-frequency ultrasound signals. Blood must be flushed away to provide clearer images. To our knowledge, no research has been performed to find the ideal flushing agent for combined optical and acoustic imaging techniques. We selected three solutions as potential flushing agents for their image-enhancing effects: mannitol, dextran, and iohexol. Testing of these flushing agents was performed in a closed-loop circulation model and in vivo on rabbits. We found that a high concentration of dextran was the most useful for simultaneous intravascular ultrasound and optical coherence tomography imaging. PMID:25985096

  11. Ideal flushing agents for integrated optical acoustic imaging systems

    NASA Astrophysics Data System (ADS)

    Li, Jiawen; Minami, Hataka; Steward, Earl; Ma, Teng; Mohar, Dilbahar; Robertson, Claire; Shung, K. Kirk; Zhou, Qifa; Patel, Pranav M.; Chen, Zhongping

    2015-02-01

    An increased number of integrated optical acoustic intravascular imaging systems have been researched and hold great hope for accurate diagnosing of vulnerable plaques and for guiding atherosclerosis treatment. However, in any intravascular environment, vascular lumen is filled with blood, which is a high-scattering source for optical and high frequency ultrasound signals. Blood must be flushed away to make images clear. To our knowledge, no research has been performed to find the ideal flushing agent that works for both optical and acoustic imaging techniques. We selected three solutions, mannitol, dextran and iohexol, as flushing agents because of their image-enhancing effects and low toxicities. Quantitative testing of these flushing agents was performed in a closed loop circulation model and in vivo on rabbits.

  12. Consensus of Hybrid Multi-Agent Systems.

    PubMed

    Zheng, Yuanshi; Ma, Jingying; Wang, Long

    2017-01-27

    In this brief, we consider the consensus problem of hybrid multiagent systems. First, the hybrid multiagent system is proposed, which is composed of continuous-time and discrete-time dynamic agents. Then, three kinds of consensus protocols are presented for the hybrid multiagent system. The analysis tool developed in this brief is based on the matrix theory and graph theory. With different restrictions of the sampling period, some necessary and sufficient conditions are established for solving the consensus of the hybrid multiagent system. The consensus states are also obtained under different protocols. Finally, simulation examples are provided to demonstrate the effectiveness of our theoretical results.

  13. Optimal Wonderful Life Utility Functions in Multi-Agent Systems

    NASA Technical Reports Server (NTRS)

    Wolpert, David H.; Tumer, Kagan; Swanson, Keith (Technical Monitor)

    2000-01-01

    The mathematics of Collective Intelligence (COINs) is concerned with the design of multi-agent systems so as to optimize an overall global utility function when those systems lack centralized communication and control. Typically in COINs each agent runs a distinct Reinforcement Learning (RL) algorithm, so that much of the design problem reduces to how best to initialize/update each agent's private utility function, as far as the ensuing value of the global utility is concerned. Traditional team game solutions to this problem assign to each agent the global utility as its private utility function. In previous work we used the COIN framework to derive the alternative Wonderful Life Utility (WLU), and experimentally established that having the agents use it induces global utility performance up to orders of magnitude superior to that induced by use of the team game utility. The WLU has a free parameter (the clamping parameter) which we simply set to zero in that previous work. Here we derive the optimal value of the clamping parameter, and demonstrate experimentally that using that optimal value can result in significantly improved performance over that of clamping to zero, over and above the improvement beyond traditional approaches.

  14. Surfactant-Based Chemical and Biological Agent Decontaminating Solution Development

    DTIC Science & Technology

    2003-11-19

    10^8 4 PAA in uEm 10^8 8 (1) C10 Amine oxide (2) di-C10 Amine oxide ! Peracetic Acid (PAA) Found to Be an Effective Disinfectant Decon Conf 11-03...Utilize as Environmentally Green Reactant for Both Chemical and Biological Agents – Some Peracids Available in Neat Form ( Peracetic acid ) and In-Situ...Formulation Components – Peroxygen Compounds and Catalysts Oxidation of Calmagite Dye by Peracetic Acid TAML FeMB Catalyst 0 20 40 60 80 100 120 0 2 4 6

  15. Multimedia agent monitoring and assessment system

    NASA Astrophysics Data System (ADS)

    Gilmore, John F.; Pagels, Michael A.; Palk, Justin

    2001-03-01

    The explosion of Information Technology (IT) in the commercial sector in the 1990's has led to billion dollar corporations overtaking the US Government (e.g., DARPA, NSF) as the leaders in IT research and development. The tenacity of the IT industry in accelerating technology development, in response to commercial demands, has actually provided government organizations with a unique opportunity to incorporate robust commercial IT into their individual applications. This development allows government agencies to focus their limited funds on the application aspects of their problems by leveraging commercial information technology developments. This paradigm applies directly to counterdrug enforcement and support. This paper describes a system that applies the state-of-the-art in information technology to news and information exploitation to produce a Multi-media Agent Monitoring and Assessment (MAMA) system capable of tracking information for field agent use, identifying assets of organizations and individuals for seizure, and disrupting drug shipping routes.

  16. A Multi-Agent System Architecture for Sensor Networks

    PubMed Central

    Fuentes-Fernández, Rubén; Guijarro, María; Pajares, Gonzalo

    2009-01-01

    The design of the control systems for sensor networks presents important challenges. Besides the traditional problems about how to process the sensor data to obtain the target information, engineers need to consider additional aspects such as the heterogeneity and high number of sensors, and the flexibility of these networks regarding topologies and the sensors in them. Although there are partial approaches for resolving these issues, their integration relies on ad hoc solutions requiring important development efforts. In order to provide an effective approach for this integration, this paper proposes an architecture based on the multi-agent system paradigm with a clear separation of concerns. The architecture considers sensors as devices used by an upper layer of manager agents. These agents are able to communicate and negotiate services to achieve the required functionality. Activities are organized according to roles related with the different aspects to integrate, mainly sensor management, data processing, communication and adaptation to changes in the available devices and their capabilities. This organization largely isolates and decouples the data management from the changing network, while encouraging reuse of solutions. The use of the architecture is facilitated by a specific modelling language developed through metamodelling. A case study concerning a generic distributed system for fire fighting illustrates the approach and the comparison with related work. PMID:22303172

  17. A multi-agent system architecture for sensor networks.

    PubMed

    Fuentes-Fernández, Rubén; Guijarro, María; Pajares, Gonzalo

    2009-01-01

    The design of the control systems for sensor networks presents important challenges. Besides the traditional problems about how to process the sensor data to obtain the target information, engineers need to consider additional aspects such as the heterogeneity and high number of sensors, and the flexibility of these networks regarding topologies and the sensors in them. Although there are partial approaches for resolving these issues, their integration relies on ad hoc solutions requiring important development efforts. In order to provide an effective approach for this integration, this paper proposes an architecture based on the multi-agent system paradigm with a clear separation of concerns. The architecture considers sensors as devices used by an upper layer of manager agents. These agents are able to communicate and negotiate services to achieve the required functionality. Activities are organized according to roles related with the different aspects to integrate, mainly sensor management, data processing, communication and adaptation to changes in the available devices and their capabilities. This organization largely isolates and decouples the data management from the changing network, while encouraging reuse of solutions. The use of the architecture is facilitated by a specific modelling language developed through metamodelling. A case study concerning a generic distributed system for fire fighting illustrates the approach and the comparison with related work.

  18. System design for robot agent team

    NASA Astrophysics Data System (ADS)

    Young, Stuart H.; Nguyen, Hung M.

    2002-07-01

    Small air and ground physical agents (robots) will be ubiquitous on the battlefield of the 21st century, principally to lower the exposure to harm of our ground forces in urban and open terrain. Teams of small collaborating physical agents conducting tasks such as Reconnaissance, Surveillance, and Target Acquisition (RSTA), intelligence, chemical and biological agent detection, logistics, decoy, sentry, and communications relay will have advanced sensors, communications, and mobility characteristics. The Army Research Laboratory (ARL) is conducting research in sensor fusion, communications, and processing on small mobile robotic platforms principally in the urban environment in support of Military Operations in Urban Terrain (MOUT). This paper discusses on-going research at ARL that supports the development of multi-robot collaboration. Commercial ATRV-2 and Urban Robot platforms are being utilized along with advanced battlefield visualization tools and other tools to effectively command and control teams of collaborating physical agents and present the gathered information in a manner that is useful to the commander. The software architecture and the modular packaging designs will be the focus of the paper, which also consider mother ship concepts. Additionally, work that has been conducted with PM Soldier Systems to integrate robotic platforms (Robot Warrior) with the Land Warrior (LW) ensemble to create a Scout Warrior will be discussed.

  19. Chemical Warfare Agent Decontaminant Solution Using Quaternary Ammonium Complexes

    DTIC Science & Technology

    1997-12-11

    peracetate, perborate monohydrate, perborate tetrahydrate, monoperoxyphthalate, peroxoymonosulfate, peroxydisulfate, and percarbonate. Still other...with sodium perborate tetrahydrate (2 g), they were then added to a heated (about 45 °C) 2 0 mixture of propylene glycol (68 g) and 2-amino-2-methyl-l...propanol (12 g). The propylene glycol-2-amino-2-methyl-l-propanol solution was heated to aid the dissolution of the sodium perborate tetrahydrate

  20. Learning in engineered multi-agent systems

    NASA Astrophysics Data System (ADS)

    Menon, Anup

    Consider the problem of maximizing the total power produced by a wind farm. Due to aerodynamic interactions between wind turbines, each turbine maximizing its individual power---as is the case in present-day wind farms---does not lead to optimal farm-level power capture. Further, there are no good models to capture the said aerodynamic interactions, rendering model based optimization techniques ineffective. Thus, model-free distributed algorithms are needed that help turbines adapt their power production on-line so as to maximize farm-level power capture. Motivated by such problems, the main focus of this dissertation is a distributed model-free optimization problem in the context of multi-agent systems. The set-up comprises of a fixed number of agents, each of which can pick an action and observe the value of its individual utility function. An individual's utility function may depend on the collective action taken by all agents. The exact functional form (or model) of the agent utility functions, however, are unknown; an agent can only measure the numeric value of its utility. The objective of the multi-agent system is to optimize the welfare function (i.e. sum of the individual utility functions). Such a collaborative task requires communications between agents and we allow for the possibility of such inter-agent communications. We also pay attention to the role played by the pattern of such information exchange on certain aspects of performance. We develop two algorithms to solve this problem. The first one, engineered Interactive Trial and Error Learning (eITEL) algorithm, is based on a line of work in the Learning in Games literature and applies when agent actions are drawn from finite sets. While in a model-free setting, we introduce a novel qualitative graph-theoretic framework to encode known directed interactions of the form "which agents' action affect which others' payoff" (interaction graph). We encode explicit inter-agent communications in a directed

  1. Potential agents for removal of actinides from waste solutions

    SciTech Connect

    Romanovski, V.V.; Whisenhunt, D.W.; Veeck, A.C.; Andersen, W.A.; Hoffman, D.C.; Jide, X.; White, D.; Raymond, K.N.

    1996-07-01

    The uptake of Th(IV) from nitric acid and hydrochloric acid solutions by chelating ion exchange resins containing catechol, 1,2- hydroxypyridinone (1,2-HOPO) and 3,4-hydroxypyridinone (3,4-HOPO) functional groups, has been investigated. These polystyrene based materials show excellent kinetics for uptake of Th(IV) and have a high loading capacity. Liquid/liquid extractants have also been synthesized by addition of lipophilic side chains to the chelating groups (1,2-HOPO; 3,4-HOPO; 3,2-HOPO; catecholamide; terephthalamide). The initial evaluation of the extraction properties has been carried out.

  2. Finite solutions of fully fuzzy linear system

    NASA Astrophysics Data System (ADS)

    Malkawi, Ghassan; Ahmad, Nazihah; Ibrahim, Haslinda

    2014-12-01

    The solution of Fully Fuzzy Linear System (FFLS) is normally categorized as unique, finite and infinitely many solutions. However, in the case of more than one solution, the finite or alternative solution is not detected when linear programming is considered. Therefore this paper aims to provide a method of using min-max system and absolute system to append new concept for the consistency of FFLS, which is called finite solution of FFLS, where the FFLS have more than two solutions, and not only an infinite solution.

  3. Actinide-specific complexing agents: their structural and solution chemistry

    SciTech Connect

    Raymond, K.N.; Freeman, G.E.; Kappel, M.J.

    1983-07-01

    The synthesis of a series of tetracatecholate ligands designed to be specific for Pu(IV) and other actinide(IV) ions has been achieved. Although these compounds are very effective as in vivo plutonium removal agents, potentiometric and voltammetric data indicate that at neutral pH full complexation of the Pu(IV) ion by all four catecholate groups does not occur. Spectroscopic results indicate that the tetracatecholates, 3,4,3-LICAMS and 3,4,3-LICAMC, complex Am(III). The Am(IV)/(III)-catecholate couple (where catecholate = 3,4,3-LICAMS or 3,4,3-LICAMC) is not observed, but may not be observable due to the large currents associated with ligand oxidation. However, within the potential range where ligand oxidation does not occur, these experiments indicate that the reduction potential of free Am(IV)/(III) is probably greater than or equal to + 2.6 V vs NHE or higher. Proof of the complexation of americium in the trivalent oxidation state by 3,4,3-LICAMS and 3,4,3-LICAMC elimates the possibility of tetracatholates stabilizing Am(IV) in vivo.

  4. Learning in multi-agent systems

    SciTech Connect

    Goldman, C.V.

    1996-12-31

    Learning agents acting in a multi agent environment can improve their performance. These agents might decide upon their course of action by learning about other agents with whom they interact. The learning agents can learn about the others information and rules of behavior. The agents will not need to plan their actions beforehand, each time they are asked to solve the same problem they have already solved or when dealing with similar problems.

  5. Intelligent Agent Feasibility Study. Volume 1: Agent-based System Technology

    DTIC Science & Technology

    1998-02-01

    ambitious in its scope. In OAA (Moran, Cheyer, Julia , Martin, 10 & Park, 1997), agents can operate on multiple platforms across a network, new agents can be...find the source and best price for a given item. This area of electronic commerce has been an active area for research in agent-based systems ( Chavez ...D. (1993). Towards a taxonomy of multi-agent systems. International Journal of Man-Machine Studies 36, 689-704. Chavez , A., Dreilinger, D., Guttman, R

  6. Agent Technology, Complex Adaptive Systems, and Autonomic Systems: Their Relationships

    NASA Technical Reports Server (NTRS)

    Truszkowski, Walt; Rash, James; Rouff, Chistopher; Hincheny, Mike

    2004-01-01

    To reduce the cost of future spaceflight missions and to perform new science, NASA has been investigating autonomous ground and space flight systems. These goals of cost reduction have been further complicated by nanosatellites for future science data-gathering which will have large communications delays and at times be out of contact with ground control for extended periods of time. This paper describes two prototype agent-based systems, the Lights-out Ground Operations System (LOGOS) and the Agent Concept Testbed (ACT), and their autonomic properties that were developed at NASA Goddard Space Flight Center (GSFC) to demonstrate autonomous operations of future space flight missions. The paper discusses the architecture of the two agent-based systems, operational scenarios of both, and the two systems autonomic properties.

  7. Building an adaptive agent to monitor and repair the electrical power system of an orbital satellite

    NASA Technical Reports Server (NTRS)

    Tecuci, Gheorghe; Hieb, Michael R.; Dybala, Tomasz

    1995-01-01

    Over several years we have developed a multistrategy apprenticeship learning methodology for building knowledge-based systems. Recently we have developed and applied our methodology to building intelligent agents. This methodology allows a subject matter expert to build an agent in the same way in which the expert would teach a human apprentice. The expert will give the agent specific examples of problems and solutions, explanations of these solutions, or supervise the agent as it solves new problems. During such interactions, the agent learns general rules and concepts, continuously extending and improving its knowledge base. In this paper we present initial results on applying this methodology to build an intelligent adaptive agent for monitoring and repair of the electrical power system of an orbital satellite, stressing the interaction with the expert during apprenticeship learning.

  8. Solute Transport of Negatively Charged Contrast Agents Across Articular Surface of Injured Cartilage.

    PubMed

    Kokkonen, H T; Chin, H C; Töyräs, J; Jurvelin, J S; Quinn, T M

    2017-04-01

    Solute transport through the extracellular matrix (ECM) is crucial to chondrocyte metabolism. Cartilage injury affects solute transport in cartilage due to alterations in ECM structure and solute-matrix interactions. Therefore, cartilage injury may be detected by using contrast agent-based clinical imaging. In the present study, effects of mechanical injury on transport of negatively charged contrast agents in cartilage were characterized. Using cartilage plugs injured by mechanical compression protocol, effective partition coefficients and diffusion fluxes of iodine- and gadolinium-based contrast agents were measured using high resolution microCT imaging. For all contrast agents studied, effective diffusion fluxes increased significantly, particularly at early times during the diffusion process (38 and 33% increase after 4 min, P < 0.05 for iodine and Gd-DTPA; and 76% increase after 10 min for diatrizoate, P < 0.05). Effective partition coefficients were unaffected in mechanically injured cartilage. Mechanical injury reduced PG content and collagen integrity in cartilage superficial zone. This study suggests that alterations in contrast agent diffusion flux, a non-equilibrium transport parameter, provides a more sensitive indicator for assessment of cartilage matrix integrity than partition coefficient and the equilibrium distribution of solute. These findings may help in developing clinical methods of contrast agent-based imaging to detect cartilage injury.

  9. Multi-agent robotic systems and applications for satellite missions

    NASA Astrophysics Data System (ADS)

    Nunes, Miguel A.

    robotic system has a consistent lower CPU load of 0.29 +/- 0.03 compared to 0.35 +/- 0.04 for the monolithic implementation, a 17.1 % reduction. The second contribution of this work is the development of a multi-agent robotic system for the autonomous rendezvous and docking of multiple spacecraft. To compute the maneuvers guidance, navigation and control algorithms are implemented as part of the multi-agent robotic system. The navigation and control functions are implemented using existing algorithms, but one important contribution of this section is the introduction of a new six degrees of freedom guidance method which is part of the guidance, navigation and control architecture. This new method is an explicit solution to the guidance problem, and is particularly useful for real time guidance for attitude and position, as opposed to typical guidance methods which are based on numerical solutions, and therefore are computationally intensive. A simulation scenario is run for docking four CubeSats deployed radially from a launch vehicle. Considering fully actuated CubeSats, the simulations show docking maneuvers that are successfully completed within 25 minutes which is approximately 30% of a full orbital period in low earth orbit. The final section investigates the problem of optimization of satellite constellations for fast revisit time, and introduces a new method to generate different constellation configurations that are evaluated with a genetic algorithm. Two case studies are presented. The first is the optimization of a constellation for rapid coverage of the oceans of the globe in 24 hours or less. Results show that for an 80 km sensor swath width 50 satellites are required to cover the oceans with a 24 hour revisit time. The second constellation configuration study focuses on the optimization for the rapid coverage of the North Atlantic Tracks for air traffic monitoring in 3 hours or less. The results show that for a fixed swath width of 160 km and for a 3 hour

  10. Gossip-Based Solutions for Discrete Rendezvous in Populations of Communicating Agents

    PubMed Central

    Hollander, Christopher D.; Wu, Annie S.

    2014-01-01

    The objective of the rendezvous problem is to construct a method that enables a population of agents to agree on a spatial (and possibly temporal) meeting location. We introduce the buffered gossip algorithm as a general solution to the rendezvous problem in a discrete domain with direct communication between decentralized agents. We compare the performance of the buffered gossip algorithm against the well known uniform gossip algorithm. We believe that a buffered solution is preferable to an unbuffered solution, such as the uniform gossip algorithm, because the use of a buffer allows an agent to use multiple information sources when determining its desired rendezvous point, and that access to multiple information sources may improve agent decision making by reinforcing or contradicting an initial choice. To show that the buffered gossip algorithm is an actual solution for the rendezvous problem, we construct a theoretical proof of convergence and derive the conditions under which the buffered gossip algorithm is guaranteed to produce a consensus on rendezvous location. We use these results to verify that the uniform gossip algorithm also solves the rendezvous problem. We then use a multi-agent simulation to conduct a series of simulation experiments to compare the performance between the buffered and uniform gossip algorithms. Our results suggest that the buffered gossip algorithm can solve the rendezvous problem faster than the uniform gossip algorithm; however, the relative performance between these two solutions depends on the specific constraints of the problem and the parameters of the buffered gossip algorithm. PMID:25397882

  11. Gossip-based solutions for discrete rendezvous in populations of communicating agents.

    PubMed

    Hollander, Christopher D; Wu, Annie S

    2014-01-01

    The objective of the rendezvous problem is to construct a method that enables a population of agents to agree on a spatial (and possibly temporal) meeting location. We introduce the buffered gossip algorithm as a general solution to the rendezvous problem in a discrete domain with direct communication between decentralized agents. We compare the performance of the buffered gossip algorithm against the well known uniform gossip algorithm. We believe that a buffered solution is preferable to an unbuffered solution, such as the uniform gossip algorithm, because the use of a buffer allows an agent to use multiple information sources when determining its desired rendezvous point, and that access to multiple information sources may improve agent decision making by reinforcing or contradicting an initial choice. To show that the buffered gossip algorithm is an actual solution for the rendezvous problem, we construct a theoretical proof of convergence and derive the conditions under which the buffered gossip algorithm is guaranteed to produce a consensus on rendezvous location. We use these results to verify that the uniform gossip algorithm also solves the rendezvous problem. We then use a multi-agent simulation to conduct a series of simulation experiments to compare the performance between the buffered and uniform gossip algorithms. Our results suggest that the buffered gossip algorithm can solve the rendezvous problem faster than the uniform gossip algorithm; however, the relative performance between these two solutions depends on the specific constraints of the problem and the parameters of the buffered gossip algorithm.

  12. Monitoring and Meta-Reasoning in Multi-Agent Systems

    DTIC Science & Technology

    2003-10-08

    Monitoring and Meta-Reasoning in Multi - Agent Systems 5c. PROGRAM ELEMENT NUMBER 5d. PROJECT NUMBER 5d. TASK NUMBER 6. AUTHOR(S) Professor...reasoning in multi - agent systems will be analyzed; ii)approaches for knowledge acquisition will be investigated; iii) methods of knowledge analysis...EOARD, Multi Agent Systems , Agent Based Systems 16. SECURITY CLASSIFICATION OF: 19a. NAME OF RESPONSIBLE PERSON JAMES GREENBERG a. REPORT UNCLAS

  13. Determination of trace amounts of chemical warfare agent degradation products in decontamination solutions with NMR spectroscopy.

    PubMed

    Koskela, Harri; Rapinoja, Marja-Leena; Kuitunen, Marja-Leena; Vanninen, Paula

    2007-12-01

    Decontamination solutions are used for an efficient detoxification of chemical warfare agents (CWAs). As these solutions can be composed of strong alkaline chemicals with hydrolyzing and oxidizing properties, the analysis of CWA degradation products in trace levels from these solutions imposes a challenge for any analytical technique. Here, we present results of application of nuclear magnetic resonance spectroscopy for analysis of trace amounts of CWA degradation products in several untreated decontamination solutions. Degradation products of the nerve agents sarin, soman, and VX were selectively monitored with substantially reduced interference of background signals by 1D 1H-31P heteronuclear single quantum coherence (HSQC) spectrometry. The detection limit of the chemicals was at the low part-per-million level (2-10 microg/mL) in all studied solutions. In addition, the concentration of the degradation products was obtained with sufficient confidence with external standards.

  14. Novel therapeutic agents for systemic lupus erythematosus.

    PubMed

    Gescuk, Bryan D; Davis, John C

    2002-09-01

    The last significant breakthrough in the treatment of systemic lupus erythematosus (SLE) was the use of cyclophosphamide and methylprednisolone in the treatment of lupus nephritis. Recent advances in immunology, oncology, and endocrinology have resulted in many potential therapies for SLE. These therapies include new immunosuppressants, biologic medications, tolerizing agents, immunoablation techniques, and hormonal medications. Each of these approaches will be discussed in this review. Some therapies are currently in use in clinical rheumatology practice (mycophenolate mofetil) and others are entering phase I trials (anti-BLyS monoclonal antibody). While some of these new therapies target specific inflammatory mechanisms in SLE (anti-CD40L monoclonal antibody), others work by nonspecific inhibition of the immune system (immunoablation).

  15. Pesticide Removal from Aqueous Solutions by Adding Salting Out Agents

    PubMed Central

    Moscoso, Fátima; Deive, Francisco J.; Esperança, José M. S. S.; Rodríguez, Ana

    2013-01-01

    Phase segregation in aqueous biphasic systems (ABS) composed of four hydrophilic ionic liquids (ILs): 1-butyl-3-methylimidazolium methylsulfate and 1-ethyl-3-methylimidazolium methylsulfate (CnC1im C1SO4, n = 2 and 4), tributylmethyl phosphonium methylsulfate (P4441 C1SO4) and methylpyridinium methylsulfate (C1Py C1SO4) and two high charge density potassium inorganic salts (K2CO3 and K2HPO4) were determined by the cloud point method at 298.15 K. The influence of the addition of the selected inorganic salts to aqueous mixtures of ILs was discussed in the light of the Hofmeister series and in terms of molar Gibbs free energy of hydration. The effect of the alkyl chain length of the cation on the methylsulfate-based ILs has been investigated. All the solubility data were satisfactorily correlated to several empirical equations. A pesticide (pentachlorophenol, PCP) extraction process based on the inorganic salt providing a greater salting out effect was tackled. The viability of the proposed process was analyzed in terms of partition coefficients and extraction efficiencies. PMID:24145747

  16. Hybrid Exploration Agent Platform and Sensor Web System

    NASA Technical Reports Server (NTRS)

    Stoffel, A. William; VanSteenberg, Michael E.

    2004-01-01

    A sensor web to collect the scientific data needed to further exploration is a major and efficient asset to any exploration effort. This is true not only for lunar and planetary environments, but also for interplanetary and liquid environments. Such a system would also have myriad direct commercial spin-off applications. The Hybrid Exploration Agent Platform and Sensor Web or HEAP-SW like the ANTS concept is a Sensor Web concept. The HEAP-SW is conceptually and practically a very different system. HEAP-SW is applicable to any environment and a huge range of exploration tasks. It is a very robust, low cost, high return, solution to a complex problem. All of the technology for initial development and implementation is currently available. The HEAP Sensor Web or HEAP-SW consists of three major parts, The Hybrid Exploration Agent Platforms or HEAP, the Sensor Web or SW and the immobile Data collection and Uplink units or DU. The HEAP-SW as a whole will refer to any group of mobile agents or robots where each robot is a mobile data collection unit that spends most of its time acting in concert with all other robots, DUs in the web, and the HEAP-SWs overall Command and Control (CC) system. Each DU and robot is, however, capable of acting independently. The three parts of the HEAP-SW system are discussed in this paper. The Goals of the HEAP-SW system are: 1) To maximize the amount of exploration enhancing science data collected; 2) To minimize data loss due to system malfunctions; 3) To minimize or, possibly, eliminate the risk of total system failure; 4) To minimize the size, weight, and power requirements of each HEAP robot; 5) To minimize HEAP-SW system costs. The rest of this paper discusses how these goals are attained.

  17. Advancing the agent methodology to include the higher order of neutron anisotropy with accelerated solutions

    NASA Astrophysics Data System (ADS)

    Satvat, Nader

    With the development of new core designs for generation IV reactors with their complexity and newer fuel designs, the need for consideration of neutron anisotropic scattering is becoming important for enchasing the economy and reliability of these designs. The theory and accurate modeling of neutron anisotropy is one of the most important problems of the transport solution to neutron Boltzmann equation. A number of methods based on careful theoretical developments, were established to numerically determine the effect of anisotropy; some of these methods are: the spherical harmonics method, the so-called function method (FN), the discrete ordinate method, and the Monte Carlo method. The AGENT methodology, based on the method of characteristics, currently the most accurate neutron transport method, represents the state-of-the-art advanced neutronics simulation tool available for 2D, 3D, and full core modeling. The higher order of anisotropic scattering (with no limitation of the number of expansion) is introduced into the AGENT code. An extensive analysis is performed to verify and validate this new model. It is shown that anisotropic scattering is important to be considered for complex geometries due to high angular dependence of neutron flux. The first principle in physics were used to explain the effects of anisotropic scattering (at the level on particle interactions), importance in including the higher moments in flux development for the core designs of high heterogonous structure promoting biased scattering (at the level of heterogeneous reactor assemblies in 2D and 3D). This inclusion of higher order of anisotropic scattering as expected increased the complexity of the mathematical model which in turn increased the computational time. An analysis of the computational time dependence on anisotropic scattering and the method of characteristics resolution parameters are analyzed with accurate predictions of scaling to larger geometries. Finally, an accelerated

  18. Adaptive Multi-Agent Systems for Constrained Optimization

    NASA Technical Reports Server (NTRS)

    Macready, William; Bieniawski, Stefan; Wolpert, David H.

    2004-01-01

    Product Distribution (PD) theory is a new framework for analyzing and controlling distributed systems. Here we demonstrate its use for distributed stochastic optimization. First we review one motivation of PD theory, as the information-theoretic extension of conventional full-rationality game theory to the case of bounded rational agents. In this extension the equilibrium of the game is the optimizer of a Lagrangian of the (probability distribution of) the joint state of the agents. When the game in question is a team game with constraints, that equilibrium optimizes the expected value of the team game utility, subject to those constraints. The updating of the Lagrange parameters in the Lagrangian can be viewed as a form of automated annealing, that focuses the MAS more and more on the optimal pure strategy. This provides a simple way to map the solution of any constrained optimization problem onto the equilibrium of a Multi-Agent System (MAS). We present computer experiments involving both the Queen s problem and K-SAT validating the predictions of PD theory and its use for off-the-shelf distributed adaptive optimization.

  19. A Functional Take on Multi-Agent Systems Position Paper

    NASA Astrophysics Data System (ADS)

    Muscar, Alex; Bǎdicǎ, Costin

    2011-09-01

    Due to the rising difficulty of developing complex systems a lot of research has gone into the multi-agent paradigm over the past decades, during which a vast array of approaches for developing such systems have been proposed. Despite this fact there seems to be a gap in the MAS community between solutions that provide for expressivity and those that offer generality. It is our opinion that embedding the MAS language into a functional language we can have the best out of both worlds: we can implement the desired semantics in an abstract way, allowing us to focus on the problem domain, i.e. complex, distributed MAS. Our approach is going to be layered: (i) we start from a statically typed functional language and build an EDSL that acts as an executable specification language for single agent entities; and (ii) develop a framework for workflow-oriented coordination on top of the previous layer and investigate its use as a means of implementing agent organizations, focusing on coordination and communication.

  20. Role of pH in metal adsorption from aqueous solutions containing chelating agents on chitosan

    SciTech Connect

    Wu, F.C.; Tseng, R.L.; Juang, R.S.

    1999-01-01

    The role of pH in adsorption of Cu(II) from aqueous solutions containing chelating agents on chitosan was emphasized. Four chelating agents including ethylenediaminetetraacetic acid (EDTA), citric acid, tartaric acid, and sodium gluconate were used. It was shown that the adsorption ability of Cu(II) on chitosan from its chelated solutions varied significantly with pH variations. The competition between coordination of Cu(II) with unprotonated chitosan and electrostatic interaction of the Cu(II) chelates with protonated chitosan took place because of the change in solution pH during adsorption. The maximum adsorption capacity was obtained within each optimal pH range determined from titration curves of the chelated solutions. Coordination of Cu(II) with the unprotonated chitosan was found to dominate at pH below such an optimal pH value.

  1. Agent Architecture for Aviation Data Integration System

    NASA Technical Reports Server (NTRS)

    Kulkarni, Deepak; Wang, Yao; Windrem, May; Patel, Hemil; Wei, Mei

    2004-01-01

    This paper describes the proposed agent-based architecture of the Aviation Data Integration System (ADIS). ADIS is a software system that provides integrated heterogeneous data to support aviation problem-solving activities. Examples of aviation problem-solving activities include engineering troubleshooting, incident and accident investigation, routine flight operations monitoring, safety assessment, maintenance procedure debugging, and training assessment. A wide variety of information is typically referenced when engaging in these activities. Some of this information includes flight recorder data, Automatic Terminal Information Service (ATIS) reports, Jeppesen charts, weather data, air traffic control information, safety reports, and runway visual range data. Such wide-ranging information cannot be found in any single unified information source. Therefore, this information must be actively collected, assembled, and presented in a manner that supports the users problem-solving activities. This information integration task is non-trivial and presents a variety of technical challenges. ADIS has been developed to do this task and it permits integration of weather, RVR, radar data, and Jeppesen charts with flight data. ADIS has been implemented and used by several airlines FOQA teams. The initial feedback from airlines is that such a system is very useful in FOQA analysis. Based on the feedback from the initial deployment, we are developing a new version of the system that would make further progress in achieving following goals of our project.

  2. Johnston Atoll Chemical Agent Disposal System (JACADS)

    SciTech Connect

    Not Available

    1990-06-01

    This Final Second Supplemental Environmental Impact Statement (SSEIS) to the Johnston Atoll Chemical Agent Disposal System (JACADS) Environmental Impact Statement (EIS) assesses the effects of receiving, storing, and ultimately destructing the United States stockpile of lethal unitary chemical munitions currently stored in the Federal Republic of Germany (FRG) (European stockpile) at the Army's JACADS facility located on Johnston Atoll in the Pacific Ocean. This Final SSEIS addresses the effects of the following proposed European stockpile activities: the transport of the European stockpile from the territorial limit to Johnston Island, the unloading of munitions from transportation ships, the on-island munitions transport and handling, on-island munitions storage, the disposal of munitions in the JACADS facility, the disposal of incineration wastes, and alternatives to the proposed action. This document also updates information in the 1983 EIS and the 1988 SEIS, as appropriate. 46 refs., 10 figs., 9 tabs.

  3. A Multi-Agent System for Intelligent Online Education.

    ERIC Educational Resources Information Center

    O'Riordan, Colm; Griffith, Josephine

    1999-01-01

    Describes the system architecture of an intelligent Web-based education system that includes user modeling agents, information filtering agents for automatic information gathering, and the multi-agent interaction. Discusses information management; user interaction; support for collaborative peer-peer learning; implementation; testing; and future…

  4. A Multi-Agent System for Intelligent Online Education.

    ERIC Educational Resources Information Center

    O'Riordan, Colm; Griffith, Josephine

    1999-01-01

    Describes the system architecture of an intelligent Web-based education system that includes user modeling agents, information filtering agents for automatic information gathering, and the multi-agent interaction. Discusses information management; user interaction; support for collaborative peer-peer learning; implementation; testing; and future…

  5. Development of a Persistent Chemical Agent Simulator System (PCASS)

    NASA Technical Reports Server (NTRS)

    Mcginness, W. G.

    1983-01-01

    The development of a persistent chemical agent simulation system (PCASS) is described. This PCASS is to be used for the military training of troops to simulate actual chemical warfare. The purpose of this system is to facilitate in the determination of chemical contamination and effectiveness of decontamination for training purposes. The fluorescent tracer employed has no daylight activation, but yet is easily removed with a decontaminate solution or water and surfactants. Also employed is a time delayed color developing system. When an individual is subjected to the PCASS and does not decontaminate adequately, red blotches or red coloration will develop as a function of time and temperature. The intent of this is to simulate the delayed chemical reaction of mustard contaminates.

  6. Health governance: principal-agent linkages and health system strengthening.

    PubMed

    Brinkerhoff, Derick W; Bossert, Thomas J

    2014-09-01

    Governance is increasingly recognized as an important factor in health system performance, yet conceptually and practically it remains poorly understood and subject to often vague and competing notions of both what its role is and how to address its weaknesses. This overview article for the symposium on health governance presents a model of health governance that focuses on the multiplicity of societal actors in health systems, the distribution of roles and responsibilities among them and their ability and willingness to fulfil these roles and responsibilities. This focus highlights the principal-agent linkages among actors and the resulting incentives for good governance and health system performance. The discussion identifies three disconnects that constitute challenges for health system strengthening interventions that target improving governance: (1) the gap between the good governance agenda and existing capacities, (2) the discrepancy between formal and informal governance and (3) the inattention to sociopolitical power dynamics. The article summarizes the three country cases in the symposium and highlights their governance findings: health sector reform in China, financial management of health resources in Brazilian municipalities and budget reform in hospitals in Lesotho. The concluding sections clarify how the three cases apply the model's principal-agent linkages and highlight the importance of filling the gaps remaining between problem diagnosis and the development of practical guidance that supports 'best fit' solutions and accommodates political realities in health systems strengthening.

  7. An Agent-Based Data Mining System for Ontology Evolution

    NASA Astrophysics Data System (ADS)

    Hadzic, Maja; Dillon, Darshan

    We have developed an evidence-based mental health ontological model that represents mental health in multiple dimensions. The ongoing addition of new mental health knowledge requires a continual update of the Mental Health Ontology. In this paper, we describe how the ontology evolution can be realized using a multi-agent system in combination with data mining algorithms. We use the TICSA methodology to design this multi-agent system which is composed of four different types of agents: Information agent, Data Warehouse agent, Data Mining agents and Ontology agent. We use UML 2.1 sequence diagrams to model the collaborative nature of the agents and a UML 2.1 composite structure diagram to model the structure of individual agents. The Mental Heath Ontology has the potential to underpin various mental health research experiments of a collaborative nature which are greatly needed in times of increasing mental distress and illness.

  8. Designing Agent Utilities for Coordinated, Scalable and Robust Multi-Agent Systems

    NASA Technical Reports Server (NTRS)

    Tumer, Kagan

    2005-01-01

    Coordinating the behavior of a large number of agents to achieve a system level goal poses unique design challenges. In particular, problems of scaling (number of agents in the thousands to tens of thousands), observability (agents have limited sensing capabilities), and robustness (the agents are unreliable) make it impossible to simply apply methods developed for small multi-agent systems composed of reliable agents. To address these problems, we present an approach based on deriving agent goals that are aligned with the overall system goal, and can be computed using information readily available to the agents. Then, each agent uses a simple reinforcement learning algorithm to pursue its own goals. Because of the way in which those goals are derived, there is no need to use difficult to scale external mechanisms to force collaboration or coordination among the agents, or to ensure that agents actively attempt to appropriate the tasks of agents that suffered failures. To present these results in a concrete setting, we focus on the problem of finding the sub-set of a set of imperfect devices that results in the best aggregate device. This is a large distributed agent coordination problem where each agent (e.g., device) needs to determine whether to be part of the aggregate device. Our results show that the approach proposed in this work provides improvements of over an order of magnitude over both traditional search methods and traditional multi-agent methods. Furthermore, the results show that even in extreme cases of agent failures (i.e., half the agents failed midway through the simulation) the system's performance degrades gracefully and still outperforms a failure-free and centralized search algorithm. The results also show that the gains increase as the size of the system (e.g., number of agents) increases. This latter result is particularly encouraging and suggests that this method is ideally suited for domains where the number of agents is currently in the

  9. Multi-agent systems design for aerospace applications

    NASA Astrophysics Data System (ADS)

    Waslander, Steven L.

    2007-12-01

    Engineering systems with independent decision makers are becoming increasingly prevalent and present many challenges in coordinating actions to achieve systems goals. In particular, this work investigates the applications of air traffic flow control and autonomous vehicles as motivation to define algorithms that allow agents to agree to safe, efficient and equitable solutions in a distributed manner. To ensure system requirements will be satisfied in practice, each method is evaluated for a specific model of agent behavior, be it cooperative or non-cooperative. The air traffic flow control problem is investigated from the point of view of the airlines, whose costs are directly affected by resource allocation decisions made by the Federal Aviation Administration in order to mitigate traffic disruptions caused by weather. Airlines are first modeled as cooperative, and a distributed algorithm is presented with various global cost metrics which balance efficient and equitable use of resources differently. Next, a competitive airline model is assumed and two market mechanisms are developed for allocating contested airspace resources. The resource market mechanism provides a solution for which convergence to an efficient solution can be guaranteed, and each airline will improve on the solution that would occur without its inclusion in the decision process. A lump-sum market is then introduced as an alternative mechanism, for which efficiency loss bounds exist if airlines attempt to manipulate prices. Initial convergence results for lump-sum markets are presented for simplified problems with a single resource. To validate these algorithms, two air traffic flow models are developed which extend previous techniques, the first a convenient convex model made possible by assuming constant velocity flow, and the second a more complex flow model with full inflow, velocity and rerouting control. Autonomous vehicle teams are envisaged for many applications including mobile sensing

  10. Using NMR Spectroscopy to Investigate the Solution Behavior of Nerve Agents and Their Binding to Acetylcholinesterase

    DTIC Science & Technology

    2016-01-01

    their interpretation are explained. The phenemonon of nuclear magnetic relaxation is also described in some detail as well as how relaxation ...dynamics (MD) Nerve agent Nuclear magnetic relaxation Nuclear Overhauser effect (NOE) Solution behavior 16...NUCLEAR MAGNETIC DIPOLE MOMENT ..............................................3 5. NUCLEAR MAGNETIC RELAXATION AND MD

  11. Detection of decontamination solution chelating agents using ion selective coated-wire electrodes

    SciTech Connect

    Banks, M.L.

    1992-12-31

    This thesis explores feasibility of using coated-wire electrodes to measure chelating agent concentration. Chelating agents are often found in radioactive decontamination solutions because they aid in the removal of radionuclides from contaminated surfaces by increasing their solubility. However, this characteristic will also enhance the mobility of the radionuclide and thus its transport out of a waste disposal site. Coated-wire ion selective electrodes, based on a polyvinylchloride membrane using dioctylphthalate as a plasticizer and dinonylnaphthalenesulfonic acid as a counterion, were constructed for five commonly utilized chelating agents (ethylenediaminetetracetic acid (EDTA), nitrilotriacetic acid (NTA), citric acid, oxalic acid and tartaric add). The EDTA and NTA electrodes` calibration characteristics exhibited acceptable behavior in pure standard solutions. From data obtained while using the EDTA and NTA electrodes in a cement environment, further research needs to be done in the area of ion interference.

  12. On the Fair Division of Multiple Stochastic Pies to Multiple Agents within the Nash Bargaining Solution

    PubMed Central

    Karmperis, Athanasios C.; Aravossis, Konstantinos; Tatsiopoulos, Ilias P.; Sotirchos, Anastasios

    2012-01-01

    The fair division of a surplus is one of the most widely examined problems. This paper focuses on bargaining problems with fixed disagreement payoffs where risk-neutral agents have reached an agreement that is the Nash-bargaining solution (NBS). We consider a stochastic environment, in which the overall return consists of multiple pies with uncertain sizes and we examine how these pies can be allocated with fairness among agents. Specifically, fairness is based on the Aristotle’s maxim: “equals should be treated equally and unequals unequally, in proportion to the relevant inequality”. In this context, fairness is achieved when all the individual stochastic surplus shares which are allocated to agents are distributed in proportion to the NBS. We introduce a novel algorithm, which can be used to compute the ratio of each pie that should be allocated to each agent, in order to ensure fairness within a symmetric or asymmetric NBS. PMID:23024752

  13. Cooperative Multi-Agent Systems in Mobile Ad Hoc Networks

    DTIC Science & Technology

    2006-01-01

    COOPERATIVE MULTI - AGENT SYSTEMS IN MOBILE AD HOC NETWORKS Joseph P. Macker William Chao Myriam Abramson Ian Downard Information Technology Division...are, mobile ad hoc networking (MANET) and Multi - Agent Systems (MAS). Despite their value in enabling more autonomous network system operation...2006 to 00-00-2006 4. TITLE AND SUBTITLE Cooperative Multi - Agent Systems in Mobile Ad Hoc Networks 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c

  14. The Assessment Agent System: Design, Development, and Evaluation

    ERIC Educational Resources Information Center

    Liu, Jianhua

    2013-01-01

    This article reports the design, development, and evaluation of an online software application for assessing students' understanding of curricular content based on concept maps. This computer-based assessment program, called the Assessment Agent System, was designed by following an agent-oriented software design method. The Assessment Agent System…

  15. The Assessment Agent System: Design, Development, and Evaluation

    ERIC Educational Resources Information Center

    Liu, Jianhua

    2013-01-01

    This article reports the design, development, and evaluation of an online software application for assessing students' understanding of curricular content based on concept maps. This computer-based assessment program, called the Assessment Agent System, was designed by following an agent-oriented software design method. The Assessment Agent System…

  16. Performance of microbial fuel cells with and without Nafion solution as cathode binding agent.

    PubMed

    Huang, Yuelong; He, Zhen; Mansfeld, Florian

    2010-10-01

    The performance of tubular microbial fuel cells (MFC) with and without Nafion solution as binding agent for the cathode catalyst preparation was investigated using different electrochemical techniques. The current output of both types of MFCs was monitored as a function of time using an external resistor. The current did not change much with time and was higher for the water cell (WC) than for the Nafion cell (NC). Cell voltage (U(c))-current (I) curves were recorded using a potentiodynamic technique. From the U(c)-I curves power concentration (P)-I and P-U(c) curves were constructed. The water cell (without Nafion) also achieved a higher maximum power output. The internal resistance that was determined from the cell voltage at which the power concentration reached its maximum value was higher for the NC than that for the WC, possibly due to the higher cathodic polarization resistance of the NC cell. The impedance for the cathodes decreased with exposure time for both cells due to increased porosity of the surface layers covering the cathode materials. No changes of the impedance were observed for the WC anode. For the NC anode the impedance spectra changed from a one-time constant system to a two-time constant system at the longer exposure time. 2010 Elsevier B.V. All rights reserved.

  17. VOLTTRON: An Agent Execution Platform for the Electric Power System

    SciTech Connect

    Akyol, Bora A.; Haack, Jereme N.; Ciraci, Selim; Carpenter, Brandon J.; Vlachopoulou, Maria; Tews, Cody W.

    2012-06-05

    Volttron is an agent execution platform that is engineered for use in the electric power system. Volttron provides resource guarantees for agents and the platform including memory and processor utilization; authentication and authorization services; directory services for agent and resource location; and agent mobility. Unlike most other agent platforms, Volttron does not depend on a single agent authoring language. Instead, we chose to design and implement Volttron as a platform service and framework that is decoupled from the agent execution environment. A prototype implementation of Volttron has been written in Python (using Python v2.7.2) and we have executed agents written in Python and Java and as shell scripts. The intended use of Volttron is in the power distribution system for managing distributed generation, demand-response, and plug-in electric vehicles.

  18. A Multi-Agent Approach for Complex System Design

    DTIC Science & Technology

    2003-06-01

    Cloud Cedex France irene.degirmenciyan@dassault-aviation.fr Abstract: Multi - agent systems that arose from research in Distributed Artificial Intelligence...and control which make it quasi autonomous. After a brief overview of the required notions to understand the multi - agent systems ’ domain, we describe...reorganise themselves. 1. Introduction Multi - agent systems that arose from research in Distributed Artificial Intelligence are now considered as a new

  19. Agent Based Velocity Control of Highway Systems

    DTIC Science & Technology

    1997-09-01

    the vector of behavior functions, C" is the behavior modification function for the i-th agent, and ai is the command action issued by the i-th agent...in a Lie-Taylor series [10]. In particular, we can express the change in the behavior modification functions C" due to the flow over the interval...the model formulated in expression (13). At time t and at point p G M the behavior modification function of agent i is given by: Crip, t) = Cf (p

  20. Impact of a Reducing Agent on the Dynamic Surface Properties of Lysozyme Solutions.

    PubMed

    Tihonov, Michael M; Kim, Viktoria V; Noskov, Boris A

    2016-05-01

    Disulfide bond shuffling in the presence of the reducing agents dithiothreitol (DTT) or β-mercaptoethanol (BME) strongly affects the surface properties of lysozyme solutions. The addition of 0.32 mM DTT substantially alters the kinetic dependencies of the dynamic surface elasticity and surface tension relative to those of pure protein solutions. The significant increase in the dynamic surface elasticity likely relates to the cross-linking between lysozyme molecules and the formation of a dense layer of protein globules stabilized by intermolecular disulfide bonds at the liquid/gas interface. This effect differs from the previously described influence of chaotropic denaturants, such as guanidine hydrochloride (GuHCl) and urea, on the surface properties of lysozyme solutions. If both chaotropic and reducing agents are added to protein solutions simultaneously, their effects become superimposed. In the case of mixed lysozyme/GuHCl/DTT solutions, the dynamic surface elasticity near equilibrium decreases as the GuHCl concentration increases because of the gradual loosening of the cross-linked layer of protein globules but remains much higher than that of lysozyme/GuHCl solutions.

  1. Admissible consensus for heterogeneous descriptor multi-agent systems

    NASA Astrophysics Data System (ADS)

    Yang, Xin-Rong; Liu, Guo-Ping

    2016-09-01

    This paper focuses on the admissible consensus problem for heterogeneous descriptor multi-agent systems. Based on algebra, graph and descriptor system theory, the necessary and sufficient conditions are proposed for heterogeneous descriptor multi-agent systems achieving admissible consensus. The provided conditions depend on not only the structure properties of each agent dynamics but also the topologies within the descriptor multi-agent systems. Moreover, an algorithm is given to design the novel consensus protocol. A numerical example demonstrates the effectiveness of the proposed design approach.

  2. Inaccessibility in Multi-Agent Systems

    DTIC Science & Technology

    2007-11-02

    reliable. Software agents may need to migrate e.g. in the situations where the information needs to be transformed between two mutually inaccessible...integrate the software prototype from the MRinMAS project in a timely fashion. An important development period of this project has been devoted to...footprint and message sending speed). For selected agent platforms - JADE, FIPA-OS, ZEUS, JACK, GRASSHOPPER and A–globe - the results of benchmarking are

  3. Sliding mode coordination control for multiagent systems with underactuated agent dynamics

    NASA Astrophysics Data System (ADS)

    Ghasemi, Masood; Nersesov, Sergey G.; Clayton, Garrett; Ashrafiuon, Hashem

    2014-12-01

    In this paper, we develop a new integrated coordinated control and obstacle avoidance approach for a general class of underactuated agents. We use graph-theoretic notions to characterise communication topology in the network of underactuated agents as determined by the information flow directions and captured by the graph Laplacian matrix. Obstacle avoidance is achieved by surrounding the stationary as well as moving obstacles by elliptical or other convex shapes that serve as stable periodic solutions to planar systems of ordinary differential equations and using transient trajectories of those systems to navigate the agents around the obstacles. Decentralised controllers for individual agents are designed using sliding mode control approach and are only based on data communicated from the neighbouring agents. We demonstrate the efficacy of our theoretical approach using an example of a system of wheeled mobile robots that reach and maintain a desired formation. Finally, we validate our results experimentally.

  4. Service-Oriented Agents for Collaborative Industrial Automation and Production Systems

    NASA Astrophysics Data System (ADS)

    Mendes, J. Marco; Leitão, Paulo; Restivo, Francisco; Colombo, Armando W.

    Service-oriented Multi-Agent Systems (SoMAS) is an approach to combine the fundamental characteristics of service-oriented and multi-agent methods into a new platform for industrial automation. Several research works already targeted the connection of these technologies, presenting different perspectives in how and why to join them. This research focuses on available efforts and solutions in the area of SoMAS and explains the idea behind the service-oriented agents in industrial automation. A SoMAS system is mainly composed by shared resources in form of services and their providing/requesting agents. The paper also discusses the required engineering aspects of these systems, from the internal anatomy to the interaction patterns. Parameters of flexibility, reconfiguration, autonomy and reduced development efforts were considered and they should be the trademark of SoMAS. Aiming to illustrate the proposed approach, an example of service-oriented automation agents is given.

  5. Recommendations and Low-Technology Safety Solutions Following Neuromuscular Blocking Agent Incidents.

    PubMed

    Graudins, Linda V; Downey, Glenn; Bui, Thuy; Dooley, Michael J

    2016-02-01

    Neuromuscular blocking agents (NMBs) are high-risk medications used to facilitate endotracheal intubation and artificial ventilation. In an incident at a metropolitan tertiary referral and teaching public hospital in Australia, a neurosurgical patient became unresponsive at the start of surgery. It was determined that cisatracurium was administered in error in place of midazolam; the patient was ventilated and the emergency surgery continued. Two additional non-operating room (OR) drug-swap cases involving cisatracurium were reported within 12 months of this event, resulting in a comprehensive review of NMB safety. A root cause analysis (RCA) resulted in multiple interventions to decrease the risk of selection and administration errors: (1) review of NMB packaging and introduction of in-house NMB labeling by pharmacy procurement staff before distribution; (2) implementation of a medication administration in anesthetics guideline with ongoing education; (3) audit of storage with removal of NMBs; (4) review of new products by medication safety pharmacists and a senior anesthetist before distribution; and (5) use of red-barrel syringes for administering NMBs was expanded to all areas using NMBs to minimize syringe-swap incidents. In the four years since full implementation of interventions, there have been no reports of cisatracurum selection errors. An incident of atracurium administration resulted in further recommendations for review of OR cart storage. Ongoing monitoring via medication safety walkrounds, by OR staff, by the perioperative pharmacist, and through the hospital's medication incident monitoring system has not detected any further NMB incidents. Technological solutions have been shown to decrease the risk of NMB errors, yet multifaceted low-technology solutions may be an effective, cheaper alternative.

  6. Crystallization and tile separation in the multi-agent systems

    NASA Astrophysics Data System (ADS)

    Collet, Jacques Henri; Fanchon, Jean

    2015-10-01

    This paper deals with the self-organization of simple mobile agents confined in a two-dimension rectangular area. Each agent interacts with its neighbors inside an interaction disk and moves following various types of force-driven couplings (e.g. repulsion or attraction). The agents do not know their absolute position, do not exchange messages, have no memory, and no learning capabilities. We first study the self-organization appearing in systems made-up with one sole type of agents, initially generated at random in the terrain. By changing the agent-agent repulsive interaction, we observe five different population reorganizations, namely, grouping, diffusion (that is classical), but especially interesting, crystallization (i.e., the agents group together on the vertices a regular hexagonal lattice), alignment along straight lines, and vortex dynamics. Then, we consider reorganization in systems made-up from two to five types of agents, where each pair of agent types has specific interaction parameters. The main result of this work is to show that, by only changing the agent-agent repulsion rules, one can generate hexagonal or rectangular multi-agent crystals or on the contrary, induce complete separation in regular hexagonal tiles.

  7. Aquatic toxicity of the decontamination agent: Multipurpose (DAM) decontamination solution. Final report, May-December 1992

    SciTech Connect

    Haley, M.V.; Kurnas, C.W.; Chester, N.A.; Muse, W.T.

    1994-05-01

    A new formulation, Decontaminating Agent: Multipurpose (DAM) Decontamination Solution, is being considered as a replacement to the DS-2 decontaminating solution. The new formulation is composed of calcium hypochlorite and N-cyclohexyl-2-pyrrolidinone. Since this is a new formulation little environmental data exists. To estimate potential impact to an aquatic environment, Daphnia magna and Photobacterium phosphoreum (a luminescent marine bacterium) were exposed to the DAM solution and to the individual components (Calcium hypochlorite and N-cyclohexyl-2-pyrrolidinone). The toxicity of the DAM solution to D. magna and P. phosphoreum was 5000 and 0.00053, respectively (highly toxic). The toxicity of calcium hypochlorite' and N-cyclohexyl-2-pyrrolidinone to daphnia was 0.04 mg/L (highly toxic) and 107 mg/L (moderately toxic), respectively.

  8. Approaches to improve the stability of the antiviral agent UC781 in aqueous solutions.

    PubMed

    Damian, Festo; Fabian, Judit; Friend, David R; Kiser, Patrick F

    2010-08-30

    In this work, we evaluated the chemical stability profiles of UC781 based solutions to identify excipients that stabilize the microbicidal agent UC781. When different antioxidants were added to UC781 in sulfobutylether-beta-cyclodextrin (SBE-beta-CD) solutions and subjected to a 50 degrees C stability study, it was observed that EDTA was a better stabilizing agent than sodium metabisulfite, glutathione or ascorbic acid. Some antioxidants accelerated the degradation of UC781, suggesting metal-catalyzed degradation of UC781. Furthermore, we observed substantial degradation of UC781 when stored in 1% Tween 80 and 1% DMSO solutions alone or in those with 10mM EDTA. On the other hand, improved stability of UC781 in the presence of 100 and 200mM of EDTA was observed in these solutions. The addition of both EDTA and citric acid in the stock solutions resulted in recovery of more than 60% of UC781 after 12 weeks. Generally, 10% SBE-beta-CD in the presence of EDTA and citric acid stabilized UC781 solutions: the amount of UC781 recovered approaching 95% after 12 weeks of storage at 40 degrees C. We also showed that the desulfuration reaction of the UC781 thioamide involves oxygen by running solution stability studies in deoxygenated media. Improved stability of UC781 in the present study indicates that the incorporation of EDTA, citric acid and SBE-beta-CD and the removal of oxygen in formulations of this drug will aid in increasing the stability of UC781 where solutions of the drug are required.

  9. Second harmonic generation from silver nanoparticles in aqueous solution with different protective agents

    NASA Astrophysics Data System (ADS)

    Ngo, Hoang M.; Ledoux-Rak, Isabelle

    2014-08-01

    Nanometer-sized metallic colloidal particles with plasmonic resonances in the visible range are widely investigated for their attractive optical properties as sensors, for imaging and cancer treatment. Their second-order nonlinear optical properties are remarkably high. In this work, silver colloidal solutions have been synthesized by a simple and quick method in aqueous solutions with different protective agents (PVA, PVP). The first hyperpolarizability β values of Ag per atom and per particle for nanospheres at 1064 nm have been measured. Silver nanoparticles, which possess intense visible region surface plasmon absorption bands, prove to be excellent nonlinear scatterers.

  10. A Methodology for Developing Environmental Information Systems with Software Agents

    NASA Astrophysics Data System (ADS)

    Athanasiadis, Ioannis N.; Mitkas, Pericles A.

    This article presents a unifying methodology for developing environmental information systems with software agents. Based on the experience reported in recent literature, we abstract common requirements of environmental information systems into agent types, combine state-of-the-art tools from computer science, service-oriented software engineering and artificial intelligence domains, as software agents and machine learning, and illustrate their potential for solving real-world problems. Specifically, two generic agent types are specified that behave as information carriers and decision makers, which provide an appropriate abstraction for deployment of added-value services in environmental information systems.

  11. A Methodology For Developing an Agent Systems Reference Architecture

    DTIC Science & Technology

    2010-05-01

    are the start- ing point for the analysis process. 2.3 The Agent Systems Reference Architecture The Agent Systems Reference Architecture (ASRA) is an...process diagram from the common features across the agent framework implementations while documenting differences as points of variation. This abstract...architecture for the functional concept and the points for variation comprise the Process View. 3. Construct the Implementation View using the static

  12. Trust Management in an Agent-Based Grid Resource Brokering System-Preliminary Considerations

    NASA Astrophysics Data System (ADS)

    Ganzha, M.; Paprzycki, M.; Lirkov, I.

    2007-10-01

    It has been suggested that utilization of autonomous software agents in computational Grids may deliver the needed functionality to speed-up Grid adoption. I our recent work we have outlined an approach in which agent teams facilitate Grid resource brokering and management. One of the interesting questions is how to manage trust in such a system. The aim of this paper is to outline our proposed solution.

  13. NOTE: The effects of paramagnetic contrast agents on metabolite protons in aqueous solution

    NASA Astrophysics Data System (ADS)

    Murphy, Philip S.; Leach, Martin O.; Rowland, Ian J.

    2002-03-01

    The longitudinal (R1) and transverse (R2) relaxivities of the clinically used contrast agents Gd(DTPA)2-, Gd(DOTA)- and Gd(DTPA-BMA) have been determined in mixed aqueous metabolite solutions for choline, creatine and N-acetylaspartate. Measurements were performed at 1.5 T using a STEAM sequence on 25 mM metabolite solutions at pH = 7.4 and 22 °C. The data showed that for all the contrast agents and metabolites, R1 ~ R2. The largest range of relaxivity values was found for Gd(DTPA)2-, where R2 = 6.8 +/- 0.3 mM-1 s-1 for choline and 1.5 +/- 0.4 mM-1 s-1 for N-acetylaspartate. Variation in relaxivity values was attributed primarily to differences between the charges of the paramagnetic agent and metabolite. The maximum potential influence of the contrast agents on in vivo metabolite signals was calculated using the measured relaxivities.

  14. Comparison of crystal and solution hemoglobin binding of selected antigelling agents and allosteric modifiers

    SciTech Connect

    Mehanna, A.S.; Abraham, D.J. )

    1990-04-24

    This paper details comprehensive binding studies (solution and X-ray) of human hemoglobin A with a group of halogenated carboxylic acids that were investigated as potential antisickling agents. It is, to our knowledge, the first study to compare solution and crystal binding for a series of compounds under similar high-salt conditions used for cocrystallization. The compounds include ((3,4-dichlorobenzyl)oxy)acetic acid, ((p-bromobenzyl)oxy)acetic acid, clofibric acid, and bezafibrate. The location and stereochemistry of binding sites have been established by X-ray crystallography, while the number of binding sites and affinity constants were measured by using equilibrium dialysis. The observed crystal structures are consistent with the binding observed in solution and that the number of binding sites is independent of salt concentration, while the binding constant increases with increasing salt concentration. The studies also reveal that relatively small changes in the chemical structure of a drug molecule can result in entirely different binding sites on the protein. Moreover, the X-ray studies provide a possible explanation for the multiplicity in function exhibited by these compounds as allosteric modulators and/or antisickling agents. Finally, the studies indicate that these compounds bind differently to the R and T states of hemoglobin, and observation of special significance to the original design of these agents.

  15. Nondestructive Intervention to Multi-Agent Systems through an Intelligent Agent

    PubMed Central

    Han, Jing; Wang, Lin

    2013-01-01

    For a given multi-agent system where the local interaction rule of the existing agents can not be re-designed, one way to intervene the collective behavior of the system is to add one or a few special agents into the group which are still treated as normal agents by the existing ones. We study how to lead a Vicsek-like flocking model to reach synchronization by adding special agents. A popular method is to add some simple leaders (fixed-headings agents). However, we add one intelligent agent, called ‘shill’, which uses online feedback information of the group to decide the shill's moving direction at each step. A novel strategy for the shill to coordinate the group is proposed. It is strictly proved that a shill with this strategy and a limited speed can synchronize every agent in the group. The computer simulations show the effectiveness of this strategy in different scenarios, including different group sizes, shill speed, and with or without noise. Compared to the method of adding some fixed-heading leaders, our method can guarantee synchronization for any initial configuration in the deterministic scenario and improve the synchronization level significantly in low density groups, or model with noise. This suggests the advantage and power of feedback information in intervention of collective behavior. PMID:23658695

  16. Nondestructive intervention to multi-agent systems through an intelligent agent.

    PubMed

    Han, Jing; Wang, Lin

    2013-01-01

    For a given multi-agent system where the local interaction rule of the existing agents can not be re-designed, one way to intervene the collective behavior of the system is to add one or a few special agents into the group which are still treated as normal agents by the existing ones. We study how to lead a Vicsek-like flocking model to reach synchronization by adding special agents. A popular method is to add some simple leaders (fixed-headings agents). However, we add one intelligent agent, called 'shill', which uses online feedback information of the group to decide the shill's moving direction at each step. A novel strategy for the shill to coordinate the group is proposed. It is strictly proved that a shill with this strategy and a limited speed can synchronize every agent in the group. The computer simulations show the effectiveness of this strategy in different scenarios, including different group sizes, shill speed, and with or without noise. Compared to the method of adding some fixed-heading leaders, our method can guarantee synchronization for any initial configuration in the deterministic scenario and improve the synchronization level significantly in low density groups, or model with noise. This suggests the advantage and power of feedback information in intervention of collective behavior.

  17. Knee System Utilizing Personalized Solutions Instrumentation

    MedlinePlus

    ATTUNE® Knee System utilizing the TRUMATCH® Personalized Solutions Instrumentation Click Here to view the BroadcastMed, Inc. Privacy Policy and Legal Notice © 2017 BroadcastMed, Inc. All rights reserved.

  18. Knee System Utilizing Personalized Solutions Instrumentation

    MedlinePlus

    ATTUNE® Knee System utilizing the TRUMATCH® Personalized Solutions Instrumentation Click Here to view the BroadcastMed, Inc. Privacy Policy and Legal Notice © 2017 BroadcastMed, Inc. All rights reserved.

  19. Mobile Agents for Web-Based Systems Management.

    ERIC Educational Resources Information Center

    Bellavista, Paolo; Corradi, Antonio; Tarantino, Fabio; Stefanelli, Cesare

    1999-01-01

    Discussion of mobile agent technology that overcomes the limits of traditional approaches to the management of global Web systems focuses on the MAMAS (mobile agents for the management of applications and systems) management environment that uses JAVA as its implementation language. Stresses security and interoperability. (Author/LRW)

  20. Mobile Agents for Web-Based Systems Management.

    ERIC Educational Resources Information Center

    Bellavista, Paolo; Corradi, Antonio; Tarantino, Fabio; Stefanelli, Cesare

    1999-01-01

    Discussion of mobile agent technology that overcomes the limits of traditional approaches to the management of global Web systems focuses on the MAMAS (mobile agents for the management of applications and systems) management environment that uses JAVA as its implementation language. Stresses security and interoperability. (Author/LRW)

  1. Distributed Agent Based Interoperable Virtual EMR System for Healthcare System Integration.

    PubMed

    Yang, Xuebing; Miao, Yuan

    2011-06-01

    One of the major problems in health care system integration is the formidable cost of mediating between myriad vendors and policy makers for updating existing heterogeneous systems to support a great variety of standards or interfaces. To provide cost-effective healthcare system integration solution, this paper presents a Graphical User Interface state model (GUISM) for automatically exchanging information with existing healthcare software through their GUIs with no modifications needed to them. This can save the huge cost of upgrading, testing and redeploying the existing systems. By using the GUISM model, distributed agents are deployed to the client computers interacting with the local electronic medical system (EMR) for communicating with other EMR systems. The whole system is called virtual EMR system and each client in this system can request needed patient healthcare information without knowing the actual location of the data.

  2. Physical and chemical stability of proflavine contrast agent solutions for early detection of oral cancer.

    PubMed

    Kawedia, Jitesh D; Zhang, Yan-Ping; Myers, Alan L; Richards-Kortum, Rebecca R; Kramer, Mark A; Gillenwater, Ann M; Culotta, Kirk S

    2016-02-01

    Proflavine hemisulfate solution is a fluorescence contrast agent to visualize cell nuclei using high-resolution optical imaging devices such as the high-resolution microendoscope. These devices provide real-time imaging to distinguish between normal versus neoplastic tissue. These images could be helpful for early screening of oral cancer and its precursors and to determine accurate margins of malignant tissue for ablative surgery. Extemporaneous preparation of proflavine solution for these diagnostic procedures requires preparation in batches and long-term storage to improve compounding efficiency in the pharmacy. However, there is a paucity of long-term stability data for proflavine contrast solutions. The physical and chemical stability of 0.01% (10 mg/100 ml) proflavine hemisulfate solutions prepared in sterile water was determined following storage at refrigeration (4-8℃) and room temperature (23℃). Concentrations of proflavine were measured at predetermined time points up to 12 months using a validated stability-indicating high-performance liquid chromatography method. Proflavine solutions stored under refrigeration were physically and chemically stable for at least 12 months with concentrations ranging from 95% to 105% compared to initial concentration. However, in solutions stored at room temperature increased turbidity and particulates were observed in some of the tested vials at 9 months and 12 months with peak particle count reaching 17-fold increase compared to baseline. Solutions stored at room temperature were chemically stable up to six months (94-105%). Proflavine solutions at concentration of 0.01% were chemically and physically stable for at least 12 months under refrigeration. The solution was chemically stable for six months when stored at room temperature. We recommend long-term storage of proflavine solutions under refrigeration prior to diagnostic procedure. © The Author(s) 2014.

  3. Numerical solution of the Bloch equations provides insights into the optimum design of PARACEST agents for MRI.

    PubMed

    Woessner, Donald E; Zhang, Shanrong; Merritt, Matthew E; Sherry, A Dean

    2005-04-01

    Paramagnetic lanthanide complexes that display unusually slow water exchange between an inner sphere coordination site and bulk water may serve as a new class of MRI contrast agents with the use of chemical exchange saturation transfer (CEST) techniques. To aid in the design of paramagnetic CEST agents for reporting important biological indices in MRI measurements, we formulated a theoretical framework based on the modified Bloch equations that relates the chemical properties of a CEST agent (e.g., water exchange rates and bound water chemical shifts) and various NMR parameters (e.g., relaxation rates and applied B(1) field) to the measured CEST effect. Numerical solutions of this formulation for complex exchanging systems were readily obtained without algebraic manipulation or simplification. For paramagnetic CEST agents of the type used here, the CEST effect is relatively insensitive to the bound proton relaxation times, but requires a sufficiently large applied B(1) field to highly saturate the Ln(3+)-bound water protons. This in turn requires paramagnetic complexes with large Ln(3+)-bound water chemical shifts to avoid direct excitation of the exchanging bulk water protons. Although increasing the exchange rate of the bound protons enhances the CEST effect, this also causes exchange broadening and increases the B(1) required for saturation. For a given B(1), there is an optimal exchange rate that results in a maximal CEST effect. This numerical approach, which was formulated for a three-pool case, was incorporated into a MATLAB nonlinear least-square optimization routine, and the results were in excellent agreement with experimental Z-spectra obtained with an aqueous solution of a paramagnetic CEST agent containing two different types of bound protons (bound water and amide protons).

  4. Quantised consensus of multi-agent systems with nonlinear dynamics

    NASA Astrophysics Data System (ADS)

    Zhu, Yunru; Zheng, Yuanshi; Wang, Long

    2015-08-01

    This paper studies the consensus problem of first-order and second-order multi-agent systems with nonlinear dynamics and quantised interactions. Continuous-time and impulsive control inputs are designed for the multi-agent systems on the logarithmic quantised relative state measurements of agents, respectively. By using nonsmooth analysis tools, we get some sufficient conditions for the consensus of multi-agent systems under the continuous-time inputs. Compared with continuous-time control inputs, impulsive distributed control inputs just use the state variables of the systems at discrete-time instances. Based on impulsive control theory, we prove that the multi-agent systems can reach consensus by choosing proper control gains and impulsive intervals. The simulation results are given to verify the effectiveness of the theoretical results.

  5. Dissolution of metal oxides accumulated in nuclear steam generators: study of solutions containing organic chelating agents

    SciTech Connect

    Gilbert, R.; Ouellet, L.

    1985-03-01

    A study of the reactivity of ethylenediaminetetraacetic acid (EDTA), citric acid, and hydrazine for the dissolution of magnetite particles has allowed some steps of the different mechanisms to be identified. Two mechanisms are suggested: In acidic solutions, the chelating agents are adsorbed at the solid/solution interface followed by desorption of the complexed species FeH /SUB n/ L, where HnL is EDTA or citric acid, whereas in alkaline media, direct dissolution of the oxide particles takes place followed by complexation of the species Fe/sup 3 +//Fe/sup 2 +/ in solution. The hydrazine apparently reduces the Fe/sup 3 +/ ions via a surface complexing reaction involving the N/sub 2/H/sub +//sub 5/ ions, a reaction which is in competition with the protonation of the Fe/sub 3/O/sub 4/ crystal lattice. Finally, regardless of the type of oxide (Fe/sub 3/O/sub 4/, Fe/sub 2/O/sub 3/, FeOOH, CuO, or Cu/sub 2/O) or the composition of the complexing solutions, suspensions of these particles are highly unstable with respect to agglomeration or settling out, more because of the high concentration of chelating agents than their chemical characteristics.

  6. Multi-agent tasks scheduling system in software defined networks

    NASA Astrophysics Data System (ADS)

    Skobelev, P. O.; Granichin, O. N.; Budaev, D. S.; Laryukhin, V. B.; Mayorov, I. V.

    2014-05-01

    In this paper a multi-agent tasks scheduling system in software defined networks is considered. This system is designed for distribution simulation and tasks implementation on computational resources including network dynamic characteristics and topology.

  7. MASDynamics: Toward Systemic Modeling of Decentralized Agent Coordination

    NASA Astrophysics Data System (ADS)

    Sudeikat, Jan; Renz, Wolfgang

    Enabling distributed software systems to purposefully self-organize, i.e. to adapt to dynamically changing execution contexts by the collective adjustment of individual components, challenges current development practices. Since the dynamics of self-organizing systems arise from agent coaction, developers cannot directly infer the macroscopic system behavior from established agent design models. This paper plays a part in an ongoing research effort that addresses the provision of self-organizing processes as design elements, i.e. reusable patterns of agent interrelations. We propose a systemic modeling approach and support the application independent description of (inter-) agent coordination patterns by a domain specific language that allows to map interrelations of agent activity to detailed agent design models. This facilitates the separation of decentralized coordination strategies from domain specific agent implementations and enables development teams to treat nature-inspired coordination strategies, which steer self-organizing dynamics, as design concepts. In addition, we show how this modeling conception provides a declarative programming approach by the automated supplementation of conventional developed agent models with non-linear, inter-agent coordination mechanisms.

  8. An Agent-Based Framework for Building Decision Support System in Supply Chain Management

    NASA Astrophysics Data System (ADS)

    Kazemi, A.; Fazel Zarandi, M. H.

    In this study, two scenarios are presented for solving Production-Distribution Panning Problem (PDPP) in a Decision Support System (DSS) framework. In the first scenario, a Traditional Decision Support System (TDSS) is presented for PDPP and a Genetic Algorithm (GA) is used for solving it. In the second scenario, a Multi-agent Decision Support System (MADSS) is considered for PDPP and three algorithms are used for solving it: Genetic Algorithm (GA), Tabu Search (TS) and Simulated Annealing (SA). Then an algorithm is suggested by using multi-agent system and A Teams concept. The obtained results reveal that the use of MADSS delivers better solutions to us.

  9. Urothelial injury to the rabbit bladder caused by calcium dissolving agents including two new citrate solutions.

    PubMed

    Zhang, Xiang-bo; Wang, Zhi-ping; Duan, Jian-min; Duan, Guo-lan; Shi, Ting-kai; Lu, Jian-zhong; Ma, Bao-liang

    2005-08-01

    We compared the urothelial injury to the bladder caused by four agents capable of dissolving calcium salts. The solutions were administrated in an antegrade way through left ureterostomies in 54 rabbits for periods of 24, 48 and 72 h. The bladders were then removed and three routine histological sections were made for each. The following six solutions were used: physiological sodium chloride solution (Phys), artificial urine (Art), 0.03 M disodium EDTA buffered to pH 8.5 with triethanolamine (EDTA), 10% Renacidin (R), test solution 2 (S2, using D-gluconic acid-lactone and other compounds that differ from R in terms of ingredients or quantity), and test solution 1 (S1, using D-gluconic-acid instead of D-gluconic acid-lactone in S2 but keeping the other ingredients the same) for irrigation. At 24 h there was no observable urothelial damage caused by perfusion with Phys or Art; solutions R, S1 and S2 caused approximately the same level of injury to the rabbit bladder mucosa; however, irrigation with disodium-EDTA caused more serious urothelial injury than R, S1 and S2 (P<0.05, chi2-test) and may be unacceptable. The damage to bladder tissues treated with S1 and S2 was less than that caused by R, but this was not significant (P>0.05, chi2-test). Following a prolonged irrigation time, all of these solutions cause further urothelial damage, but EDTA caused the most, followed by R, S1, S2, Phys or Art, respectively, at 48 and 72 h. In view of the better solubility effect of solutions S1 and S2 compared with R, it might be justified in accepting the more pronounced urothelial irritation caused these solutions, but in order to enhance their effectiveness and reduce urothelial injury further study will be needed.

  10. AFECS. Multi-Agent Framework for Experiment Control Systems

    SciTech Connect

    Vardan Gyurjyan; David Abbott; William Heyes; Edward Jastrzembski; Carl Timmer; Elliott Wolin

    2008-01-23

    AFECS is a pure Java based software framework for designing and implementing distributed control systems. AFECS creates a control system environment as a collection of software agents behaving as finite state machines. These agents can represent real entities, such as hardware devices, software tasks, or control subsystems. A special control oriented ontology language (COOL), based on RDFS (Resource Definition Framework Schema) is provided for control system description as well as for agent communication. AFECS agents can be distributed over a variety of platforms. Agents communicate with their associated physical components using range of communication protocols, including tcl-DP, cMsg (publish-subscribe communication system developed at Jefferson Lab), SNMP (simple network management protocol), EPICS channel access protocol and JDBC.

  11. Quicker Q-Learning in Multi-Agent Systems

    NASA Technical Reports Server (NTRS)

    Agogino, Adrian K.; Tumer, Kagan

    2005-01-01

    Multi-agent learning in Markov Decisions Problems is challenging because of the presence ot two credit assignment problems: 1) How to credit an action taken at time step t for rewards received at t' greater than t; and 2) How to credit an action taken by agent i considering the system reward is a function of the actions of all the agents. The first credit assignment problem is typically addressed with temporal difference methods such as Q-learning OK TD(lambda) The second credit assi,onment problem is typically addressed either by hand-crafting reward functions that assign proper credit to an agent, or by making certain independence assumptions about an agent's state-space and reward function. To address both credit assignment problems simultaneously, we propose the Q Updates with Immediate Counterfactual Rewards-learning (QUICR-learning) designed to improve both the convergence properties and performance of Q-learning in large multi-agent problems. Instead of assuming that an agent s value function can be made independent of other agents, this method suppresses the impact of other agents using counterfactual rewards. Results on multi-agent grid-world problems over multiple topologies show that QUICR-learning can achieve up to thirty fold improvements in performance over both conventional and local Q-learning in the largest tested systems.

  12. Developing an Agent Systems Reference Architecture

    DTIC Science & Technology

    2010-05-01

    The notion of a reference architecture has different meanings based on the view- points and concerns of the stakeholders. In this work, a reference...functional concept defined by the ASRM and further elaborating actors and invoca- tion points . The intended audience are high-level practitioners who need...execution. Figure 1(a) displays the temporal view of a scenario demonstrating the invocation points of the agent mobility functional con- cept. The

  13. Verifying Multi-Agent Systems via Unbounded Model Checking

    NASA Technical Reports Server (NTRS)

    Kacprzak, M.; Lomuscio, A.; Lasica, T.; Penczek, W.; Szreter, M.

    2004-01-01

    We present an approach to the problem of verification of epistemic properties in multi-agent systems by means of symbolic model checking. In particular, it is shown how to extend the technique of unbounded model checking from a purely temporal setting to a temporal-epistemic one. In order to achieve this, we base our discussion on interpreted systems semantics, a popular semantics used in multi-agent systems literature. We give details of the technique and show how it can be applied to the well known train, gate and controller problem. Keywords: model checking, unbounded model checking, multi-agent systems

  14. Verification of heterogeneous multi-agent system using MCMAS

    NASA Astrophysics Data System (ADS)

    Choi, Jiyoung; Kim, Seungkeun; Tsourdos, Antonios

    2015-03-01

    The focus of the paper is how to model autonomous behaviours of heterogeneous multi-agent systems such that it can be verified that they will always operate within predefined mission requirements and constraints. This is done by using formal methods with an abstraction of the behaviours modelling and model checking for their verification. Three case studies are presented to verify the decision-making behaviours of heterogeneous multi-agent system using a convoy mission scenario. The multi-agent system in a case study has been extended by increasing the number of agents and function complexity gradually. For automatic verification, model checker for multi-agent systems (MCMAS) is adopted due to its novel capability to accommodate the multi-agent system and successfully verifies the targeting behaviours of the team-level autonomous systems. The verification results help retrospectively the design of decision-making algorithms improved by considering additional agents and behaviours during three steps of scenario modification. Consequently, the last scenario deals with the system composed of a ground control system, two unmanned aerial vehicles, and four unmanned ground vehicles with fault-tolerant and communication relay capabilities.

  15. Finite-time consensus for heterogeneous multi-agent systems with mixed-order agents

    NASA Astrophysics Data System (ADS)

    Sun, Fenglan; Zhu, Wei

    2015-08-01

    This paper studies the finite-time consensus for heterogeneous multi-agent systems composed of mixed-order agents over fixed and switching topologies. The control protocol of each agent using local information is designed and the detailed analysis of the finite-time consensus for fixed and switching interaction topologies is presented. The design of the finite-time consensus protocol is based on graph theory, matrix theory, and LaSalle's invariance principle. Both theoretical studies and simulation results show the effectiveness of the proposed method and the correctness of the obtained theoretical results.

  16. An impedance study of two types of stainless steel in Ringer physiological solution containing complexing agents.

    PubMed

    Slemnik, Mojca; Milosev, Ingrid

    2006-10-01

    The effect of complexing agents EDTA and citric acid on the electrochemical behaviour of AISI 304 and orthopaedic stainless steels in Ringer physiological solution was investigated by potentiodynamic polarization method and electrochemical impedance spectroscopy (EIS). The content of Mo has a pronounced effect on the corrosion resistance, as evident by the broader passive range of the orthopaedic stainless steel containing Mo. The addition of complexing agents induces significant changes in polarization and impedance characteristics, i.e., the shift of corrosion and breakdown potentials in a more negative direction, an increase in current density, and a significant decrease in charge transfer resistance. The results were interpreted by the formation of soluble complexes of metal ions with chelating agents, especially EDTA, which suppressed the formation of the outer Fe(III) layer of the passive film. The impact of complexing agent on the electrochemical parameters was found to be related to its concentration in electrolyte and the stability constant of the complex formed with the related metal ion.

  17. Specialization in multi-agent systems through learning.

    PubMed

    Murciano, A; Millán, J R; Zamora, J

    1997-05-01

    Specialization is a common feature in animal societies that leads to an improvement in the fitness of the team members and to an increase in the resources obtained by the team. In this paper we propose a simple reinforcement learning approach to specialization in an artificial multi-agent system. The system is composed of homogeneous and non-communicating agents. Because there is no communication, the number of agents in the team can easily scale up. Agents have the same initial functionalities, but they learn to specialize and so cooperate to achieve a complex gathering task efficiently. Simulation experiments show how the multi-agent system specializes appropriately so as to reach optimal (or near-to-optimal) performance in unknown and changing environments.

  18. Solution of Coulomb system in momentum space

    SciTech Connect

    Lin, D.-H.

    2008-02-15

    The solution of D-dimensional Coulomb system is solved in momentum space by path integral. From which the topological effect of a magnetic flux in the system is given. It is revealed that the flux effect represented by the two-dimensional field of Aharonov-Bohm covers any space-dimensions.

  19. Layered Learning in Multi-Agent Systems

    DTIC Science & Technology

    1998-12-15

    Learning 102 5 Learning an Individual Skill 105 5.1 Ball Interception in the Soccer Server 105 5.2 Training 107 5.3 Results 109 5.3.1 Number of...CMUnited-98 Simulator Agent Skills 217 B.l.l Kicking 217 B.1.2 Dribbling 219 B.1.3 Smart Dribbling 220 B.1.4 Ball Interception 220 B.1.5...223 B.2.2 Ball Handling 224 B.2.3 Obstacle Avoidance 225 B.2.4 Goaltending 225 B.2.5 Run-time Evaluation of Collaborative

  20. A Formal Environment Model for Multi-Agent Systems

    NASA Astrophysics Data System (ADS)

    da Silva, Paulo Salem; de Melo, Ana C. V.

    Multi-agent systems are employed to model complex systems which can be decomposed into several interacting pieces called agents. In such systems, agents exist, evolve and interact within an environment. In this paper we present a model for the specification of such environments. This Environment Model for Multi-Agent Systems (EMMAS), as we call it, defines both structural and dynamic aspects of environments. Structurally, EMMAS connects agents by a social network, in which the link between agents is specified as the capability that one agent has to act upon another. Dynamically, EMMAS provides operations that can be composed together in order to create a number of different environmental situations and to respond appropriately to agents' actions. These features are founded on a mathematical model that we provide and that defines rigorously what constitutes an environment. Formality is achieved by employing the π-calculus process algebra in order to give the semantics of this model. This allows, in particular, a simple characterization of the evolution of the environment structure. Moreover, owing to this formal semantics, it is possible to perform formal analyses on environments thus described. For the sake of illustration, a concrete example of environment specification using EMMAS is also given.

  1. Cooperative learning over composite search spaces: Experiences with a multi-agent design system

    SciTech Connect

    Prasad, M.V.N.; Lesser, V.R.; Lander, S.E.

    1996-12-31

    We suggest the use of two learning techniques - short term and long term - to enhance search efficiency in a multi-agent design system by letting the agents learn about non-local requirements on the local search process. The first technique allows an agent to accumulate and apply constraining information about global problem solving, gathered as a result of agent communication, to further problem solving within the same problem instance. The second technique is used to classify problem instances and appropriately index and retrieve constraining information to apply to new problem instances. These techniques will be presented within the context of a multi-agent parametric-design application called STEAM. We show that learning conclusively improves solution quality and processing-time results.

  2. Decontamination of adsorbed chemical warfare agents on activated carbon using hydrogen peroxide solutions.

    PubMed

    Osovsky, Ruth; Kaplan, Doron; Nir, Ido; Rotter, Hadar; Elisha, Shmuel; Columbus, Ishay

    2014-09-16

    Mild treatment with hydrogen peroxide solutions (3-30%) efficiently decomposes adsorbed chemical warfare agents (CWAs) on microporous activated carbons used in protective garments and air filters. Better than 95% decomposition of adsorbed sulfur mustard (HD), sarin, and VX was achieved at ambient temperatures within 1-24 h, depending on the H2O2 concentration. HD was oxidized to the nontoxic HD-sulfoxide. The nerve agents were perhydrolyzed to the respective nontoxic methylphosphonic acids. The relative rapidity of the oxidation and perhydrolysis under these conditions is attributed to the microenvironment of the micropores. Apparently, the reactions are favored due to basic sites on the carbon surface. Our findings suggest a potential environmentally friendly route for decontamination of adsorbed CWAs, using H2O2 without the need of cosolvents or activators.

  3. Degradation of chelating agents in aqueous solution using advanced oxidation process (AOP).

    PubMed

    Sillanpää, Mika E T; Kurniawan, Tonni Agustiono; Lo, Wai-hung

    2011-06-01

    This article presents an overview with critical analysis of technical applicability of advanced oxidation process (AOP) in removing chelating agents from aqueous solution. Apart from the effect of metals for chelating agents as a major influencing factor, selected information such as pH, oxidant's dose, concentrations of pollutants and treatment performance is presented. The performance of individual AOP is compared. It is evident from our literature survey that photocatalysis with UV irradiation alone or coupled with TiO(2), ozonation and Fenton's oxidation are frequently applied to mineralize target pollutants. Overall, the selection of the most suitable AOP depends on the characteristics of effluents, technical applicability, discharge standard, regulatory requirements and environmental impacts.

  4. Multi-agent System for Rapid TST Decision Support

    DTIC Science & Technology

    2008-06-01

    13th ICCRTS: C2 for Complex Endeavors “ Multi - agent System for Rapid TST Decision Support” Topic #5, #8 and #9 Joseph Barker, Dr. Robert...OMB control number. 1. REPORT DATE JUN 2008 2. REPORT TYPE 3. DATES COVERED 00-00-2008 to 00-00-2008 4. TITLE AND SUBTITLE Multi - agent System for...unclassified Standard Form 298 (Rev. 8-98) Prescribed by ANSI Std Z39-18 13th ICCRTS: C2 for Complex Endeavors Multi - agent System for Rapid TST Decision

  5. Spatial snowdrift game of a heterogeneous agent system: cooperative behavior

    NASA Astrophysics Data System (ADS)

    Li, Ping-Ping; Ke, Jianhong; Jiang, Luo-Luo; Yuan, Xian-Zhang; Lin, Zhenquan

    2013-04-01

    We study the cooperative behavior of an evolutionary snowdrift game in a heterogeneous system with two types of agents, in which the inner-directed agents adopt the memory-based updating rule while the copycat-like ones take the unconditional imitation rule. The equilibrium cooperation frequency in such a heterogeneous system shows plateau structures with discontinuous steplike jumps as a function of the cost-to-benefit ratio, as well in homogeneous systems only with inner-directed agents [W.-X. Wang, J. Ren, G.R. Chen, B.-H. Wang, Phys. Rev. E 74, 056113 (2006)] or copycat-like ones [P.-P. Li, J. Ke, Z. Lin, P.M. Hui, Phys. Rev. E 85, 021111 (2012)]. One nontrivial feature for the heterogenous agent system is that the number of plateaux varies non-monotonically with the composition of the two mixing agents. Moreover, there exists a worst composition of the heterogeneous agents for each plateau, leading to the lowest cooperation level. We then qualitatively interpret these features by invoking the stability of local microscopic patterns. Our results are of some help in understanding the cooperative behaviors of heterogenous agent systems, and the qualitative analysis employed here also provides a useful method for studying in depth the evolutionary dynamics of spatial games.

  6. A hybrid agent-based approach for modeling microbiological systems.

    PubMed

    Guo, Zaiyi; Sloot, Peter M A; Tay, Joc Cing

    2008-11-21

    Models for systems biology commonly adopt Differential Equations or Agent-Based modeling approaches for simulating the processes as a whole. Models based on differential equations presuppose phenomenological intracellular behavioral mechanisms, while models based on Multi-Agent approach often use directly translated, and quantitatively less precise if-then logical rule constructs. We propose an extendible systems model based on a hybrid agent-based approach where biological cells are modeled as individuals (agents) while molecules are represented by quantities. This hybridization in entity representation entails a combined modeling strategy with agent-based behavioral rules and differential equations, thereby balancing the requirements of extendible model granularity with computational tractability. We demonstrate the efficacy of this approach with models of chemotaxis involving an assay of 10(3) cells and 1.2x10(6) molecules. The model produces cell migration patterns that are comparable to laboratory observations.

  7. The Deontic Transaction Model in Multi-Agent Normative Systems

    NASA Technical Reports Server (NTRS)

    Huang, Yonghua; Esterline, Albert

    1998-01-01

    In the area of multi-agent systems, much research is devoted to the coordination of the agents. There exist several issues, two of which are summarized. The first is that, although agents are said to be autonomous, they always react in a predictable way to each message, and they cannot decide to violate the conventions that are hard-wired into the protocol. In fact, there might be circumstances in which the agent violates a convention in order to realize a private goal that it considers to be more important. Another issue is that, if the protocols that agents use to react to the environment are fixed, they have no way to respond to changes. However, an important characteristic of agents is that they eon react to a changing environment. Although transaction models ([BOH92], [GR93]) evolved from the database domain, they establish a general execution paradigm that ideally covers all the subsystems invoked in a sequence of transactions. So transaction models apply to multi-agent systems. Recently, some research has been devoted to overcoming the limitations of the traditional transaction models which are suitable for conventional systems and focus on system integrity, e,g., [SJ97]. Here we solve above issues by turning to a deontic concept: obligation. In multi-agent systems, agents interact with each other according to norms, We use deontic logic ([And58], [Aqv84], [B C96], [JS94], [MW93]) to model norms. Here the norms prescribe how the agents ought to behave, but-- and this is essential-- they do not exclude the possibility of "bad" behavior (i.e., the actual behavior may deviate from the ideal), and so they also prescribe what should be done in circumstances of norm violation. Thus, we propose a new approach --- a deontic transaction model for multi-agent normative systems. Our approach improves the protocol of "abort/commit" of traditional transaction models to a protocol of "abort/exception/commit". In multi-agent normative systems, we can see the violation of a

  8. The Deontic Transaction Model in Multi-Agent Normative Systems

    NASA Technical Reports Server (NTRS)

    Huang, Yonghua; Esterline, Albert

    1998-01-01

    In the area of multi-agent systems, much research is devoted to the coordination of the agents. There exist several issues, two of which are summarized. The first is that, although agents are said to be autonomous, they always react in a predictable way to each message, and they cannot decide to violate the conventions that are hard-wired into the protocol. In fact, there might be circumstances in which the agent violates a convention in order to realize a private goal that it considers to be more important. Another issue is that, if the protocols that agents use to react to the environment are fixed, they have no way to respond to changes. However, an important characteristic of agents is that they eon react to a changing environment. Although transaction models ([BOH92], [GR93]) evolved from the database domain, they establish a general execution paradigm that ideally covers all the subsystems invoked in a sequence of transactions. So transaction models apply to multi-agent systems. Recently, some research has been devoted to overcoming the limitations of the traditional transaction models which are suitable for conventional systems and focus on system integrity, e,g., [SJ97]. Here we solve above issues by turning to a deontic concept: obligation. In multi-agent systems, agents interact with each other according to norms, We use deontic logic ([And58], [Aqv84], [B C96], [JS94], [MW93]) to model norms. Here the norms prescribe how the agents ought to behave, but-- and this is essential-- they do not exclude the possibility of "bad" behavior (i.e., the actual behavior may deviate from the ideal), and so they also prescribe what should be done in circumstances of norm violation. Thus, we propose a new approach --- a deontic transaction model for multi-agent normative systems. Our approach improves the protocol of "abort/commit" of traditional transaction models to a protocol of "abort/exception/commit". In multi-agent normative systems, we can see the violation of a

  9. Agent-based model for the h-index - exact solution

    NASA Astrophysics Data System (ADS)

    Żogała-Siudem, Barbara; Siudem, Grzegorz; Cena, Anna; Gagolewski, Marek

    2016-01-01

    Hirsch's h-index is perhaps the most popular citation-based measure of scientific excellence. In 2013, Ionescu and Chopard proposed an agent-based model describing a process for generating publications and citations in an abstract scientific community [G. Ionescu, B. Chopard, Eur. Phys. J. B 86, 426 (2013)]. Within such a framework, one may simulate a scientist's activity, and - by extension - investigate the whole community of researchers. Even though the Ionescu and Chopard model predicts the h-index quite well, the authors provided a solution based solely on simulations. In this paper, we complete their results with exact, analytic formulas. What is more, by considering a simplified version of the Ionescu-Chopard model, we obtained a compact, easy to compute formula for the h-index. The derived approximate and exact solutions are investigated on a simulated and real-world data sets.

  10. An immunity-based anomaly detection system with sensor agents.

    PubMed

    Okamoto, Takeshi; Ishida, Yoshiteru

    2009-01-01

    This paper proposes an immunity-based anomaly detection system with sensor agents based on the specificity and diversity of the immune system. Each agent is specialized to react to the behavior of a specific user. Multiple diverse agents decide whether the behavior is normal or abnormal. Conventional systems have used only a single sensor to detect anomalies, while the immunity-based system makes use of multiple sensors, which leads to improvements in detection accuracy. In addition, we propose an evaluation framework for the anomaly detection system, which is capable of evaluating the differences in detection accuracy between internal and external anomalies. This paper focuses on anomaly detection in user's command sequences on UNIX-like systems. In experiments, the immunity-based system outperformed some of the best conventional systems.

  11. An Immunity-Based Anomaly Detection System with Sensor Agents

    PubMed Central

    Okamoto, Takeshi; Ishida, Yoshiteru

    2009-01-01

    This paper proposes an immunity-based anomaly detection system with sensor agents based on the specificity and diversity of the immune system. Each agent is specialized to react to the behavior of a specific user. Multiple diverse agents decide whether the behavior is normal or abnormal. Conventional systems have used only a single sensor to detect anomalies, while the immunity-based system makes use of multiple sensors, which leads to improvements in detection accuracy. In addition, we propose an evaluation framework for the anomaly detection system, which is capable of evaluating the differences in detection accuracy between internal and external anomalies. This paper focuses on anomaly detection in user's command sequences on UNIX-like systems. In experiments, the immunity-based system outperformed some of the best conventional systems. PMID:22291560

  12. Development of a Rapid Decontamination System for the Nerve Agents

    DTIC Science & Technology

    2006-09-15

    Decontamination System for Nerve Agents: Final Report Table of Contents Statement of Problem Studied 2 Catalyst Synthesis and Characterization...most important findings of the research and is divided into four sections: catalyst synthesis and characterization, reactor design, experiments

  13. Distribution coefficients of vitamin B2 in hydrophilic organic solvent-aqueous salt solution systems

    NASA Astrophysics Data System (ADS)

    Korenman, Ya. I.; Mokshina, N. Ya.; Zykov, A. V.

    2010-03-01

    Distribution coefficients of vitamin B2 in hydrophilic solvent ( n-butanol, isopropanol, acetone, ethyl acetate, and their mixtures)-aqueous salt (potassium chloride, sodium fluoride, and ammonium sulfate salting-out agents) solution systems were calculated. The synergic effect and optimum proportions of components in the solvent mixture for efficient extraction of vitamin B2 from aqueous solutions were established.

  14. EOS for critical slurry and solution systems

    SciTech Connect

    DiPeso, G; Peterson, P

    1998-10-27

    In a fire involving fissile material, the mixture of the fissile material ash with fire fighting water may lead to a criticality excursion if there are nearby sumps that permit a critical geometry. The severity of the resulting energy release and pressure pulse is dependent on the rate at which the mixing occurs. To calculate these excursions, a non-equilibrium equation of state for the water ash mixture or slurry is needed that accounts for the thermal non-equilibrium that occurs due to finite heat transfer rates. We are developing the slurry EOS as well as a lumped neutronic and hydrodynamic model to serve as a testing ground for the non-equilibrium EOS before its incorporation into more sophisticated neutronic-hydrodynamics codes. Though the model lacks spatial dependence, it provides estimates of energy release and pressure pulses for various mixture assembly rates. We are also developing a non-equilibrium EOS for critical solution systems in which the fissile material is dissolved in water, which accounts for chemical non-equilibrium due to finite mass transfer rates. In contrast to previously published solution EOS, our solution EOS specifically accounts for mass diffusion of dissolved radiolytic gas to bubble nucleation sites. This EOS was developed to check our overall modeling against published solution excursion experiments and to compare solution excursions with slurry excursions initiated under the same conditions. Preliminary results indicate a good match between solution EOS calculations and experiments involving premixed 60-80 g U/l solutions for both low rate and high rate reactivity insertions. Comparison between slurry and solution calculations for the same composition show comparable energy release and pressure peaks for both low and high rate reactivity insertions with the slurry releasing less energy but generating more pressure than the solution for the amount of energy released. Calculations more appropriate to actual fire fighting scenarios

  15. Forward osmosis desalination using polymer hydrogels as a draw agent: influence of draw agent, feed solution and membrane on process performance.

    PubMed

    Li, Dan; Zhang, Xinyi; Simon, George P; Wang, Huanting

    2013-01-01

    We have previously reported the use of hydrogel particles as the draw agent for forward osmosis desalination. In the present work, the effects of draw agent, feed concentration and membrane on the process performance were systematically examined. Our results showed that the incorporation of carbon filler particles in polymer hydrogels led to enhanced swelling ratios of the draw agents and thus higher water fluxes in the FO process. The composite polymer hydrogel particles of sizes ranging from 100 μm to 200 μm as draw agents induced greater water fluxes in FO desalination as compared with those with larger particle sizes (500-700 μm). Similar to other types of draw solutes, as the salt concentration in the feed increased, the water flux created by the polymer hydrogel draw agent decreased; the use of a cellulose triacetate forward osmosis membrane resulted in higher water flux compared with the use of a polyamide composite reverse osmosis membrane.

  16. Development of a persistent chemical agent simulation system

    NASA Technical Reports Server (NTRS)

    1983-01-01

    A Persistent Chemical Agent Simulation System was developed (PCASS) to simulate, for force-on-force training exercises, the field environment produced by the presence of persistent chemical agents. Such a simulant system must satisfy several requirements to be of value as a training aid. Specifically, it must provide for realistic training which will generate competency in at least the following areas: (1) detection of the persistent agent presence; (2) proper use of protective equipment and procedures; (3) determination of the extent of contamination; and (4) decontamination of equipment and personnel.

  17. Nanoparticles as strengthening agents in polymer systems

    NASA Astrophysics Data System (ADS)

    Shahid, Naureen

    2005-11-01

    Carboxylate-substituted alumina nanoparticles are produced solvent free using mechanical shear. The general nature of this method has been demonstrated for L-lysine-, stearate, and p-hydroxybenzoate-derived materials. The reaction rate and particle size is controlled by a combination of temperature and shear rate. The nanoparticles are spectroscopically equivalent to those reported from aqueous syntheses, however, the average particle size can be decreased and the particle size distribution narrowed depending on the reaction conditions. Lysine and p-hydroxybenzoato alumoxanes have been introduced in carbon fiber reinforced epoxide resin composites. Different preparation conditions have been studied to obtain composite with enhanced performances that are ideal for the motor sports and aerospace industries. A new composite material has been fabricated utilizing surface-modified carboxylate alumoxane nanoparticles and the biodegradable polymer poly(propylene fumarate)/poly(propylene fumarate)-diacrylate (PPF/PPF-DA). For this study, composites were prepared using various functional groups including: a surfactant alumoxane to enhance nanoparticle dispersion into the polymer; an activated-alumoxane to enhance nanoparticle interaction with the polymer matrix; a mixed alumoxane containing both activated and surfactant groups. Nanocomposites prepared with all types of alumoxane, as well as blank polymer resin and unmodified boehmite, underwent mechanical testing and were characterized by SEM and microprobe analysis. A nanocomposite composed of mixed alumoxane nanoparticles dispersed in PPF/PPF-DA exhibited increased flexural modulus compared to polymer resin alone, and a significant enhancement over both the activated and surfacted alumoxanes. Boric acid is used as the cross-linking agent in oil well drilling industry even though the efficacy of the borate ion, [B(OH)4]- , as a cross-linking agent is poor. The reaction product of boric acid and the polysaccharide guaran

  18. Multi-agent autonomous system and method

    NASA Technical Reports Server (NTRS)

    Fink, Wolfgang (Inventor); Dohm, James (Inventor); Tarbell, Mark A. (Inventor)

    2010-01-01

    A method of controlling a plurality of crafts in an operational area includes providing a command system, a first craft in the operational area coupled to the command system, and a second craft in the operational area coupled to the command system. The method further includes determining a first desired destination and a first trajectory to the first desired destination, sending a first command from the command system to the first craft to move a first distance along the first trajectory, and moving the first craft according to the first command. A second desired destination and a second trajectory to the second desired destination are determined and a second command is sent from the command system to the second craft to move a second distance along the second trajectory.

  19. Swarming behaviors in multi-agent systems with nonlinear dynamics.

    PubMed

    Yu, Wenwu; Chen, Guanrong; Cao, Ming; Lü, Jinhu; Zhang, Hai-Tao

    2013-12-01

    The dynamic analysis of a continuous-time multi-agent swarm model with nonlinear profiles is investigated in this paper. It is shown that, under mild conditions, all agents in a swarm can reach cohesion within a finite time, where the upper bounds of the cohesion are derived in terms of the parameters of the swarm model. The results are then generalized by considering stochastic noise and switching between nonlinear profiles. Furthermore, swarm models with limited sensing range inducing changing communication topologies and unbounded repulsive interactions between agents are studied by switching system and nonsmooth analysis. Here, the sensing range of each agent is limited and the possibility of collision among nearby agents is high. Finally, simulation results are presented to demonstrate the validity of the theoretical analysis.

  20. Swarming behaviors in multi-agent systems with nonlinear dynamics

    SciTech Connect

    Yu, Wenwu; Chen, Guanrong; Cao, Ming; Lü, Jinhu; Zhang, Hai-Tao

    2013-12-15

    The dynamic analysis of a continuous-time multi-agent swarm model with nonlinear profiles is investigated in this paper. It is shown that, under mild conditions, all agents in a swarm can reach cohesion within a finite time, where the upper bounds of the cohesion are derived in terms of the parameters of the swarm model. The results are then generalized by considering stochastic noise and switching between nonlinear profiles. Furthermore, swarm models with limited sensing range inducing changing communication topologies and unbounded repulsive interactions between agents are studied by switching system and nonsmooth analysis. Here, the sensing range of each agent is limited and the possibility of collision among nearby agents is high. Finally, simulation results are presented to demonstrate the validity of the theoretical analysis.

  1. Toxicity of Persistent Chemical Agents Simulants (PCAS) and Chemical Agent Disclosure Solution (CADS) in Soil on Cucumber (Cucumis sativus, L.) and Earthworms (Eisenia foetida)

    DTIC Science & Technology

    1991-03-01

    SOLUTION (CADS) IN SOIL ON CUCUMBER (Cucumis sativus, L.) AND EARTHWORMS (Eisenia foetida ) Carlton T. Phillips Randall S. Wentsel Ronald T. Checkai...Eisenia foetida ) 6. AUTHOR(S) Phillips, Carlton T.; Wentsel, Randall S.; and Checkai, Ronald T. 7. PERFORMING ORGANIZATION NAME(S) AND ADORESS(ES) 8...Terrestrial plants 38 Chemical agent disclosure solution Phytotoxicity Is. PRICE CODE Earthworms (Eisenia foetida ) Cucumber (Cucumis sativus, L. 17

  2. A Multi-Agent System Approach for Distance Learning Architecture

    ERIC Educational Resources Information Center

    Turgay, Safiye

    2005-01-01

    The goal of this study is to suggest the agent systems by intelligence and adaptability properties in distance learning environment. The suggested system has flexible, agile, intelligence and cooperation features. System components are teachers, students (learners), and resources. Inter component relations are modeled and reviewed by using the…

  3. A haemostatic agent delivery system for endoscopic neurosurgical procedures.

    PubMed

    Waran, V; Sek, K; Bahuri, N F; Narayanan, P; Chandran, H

    2011-10-01

    In endoscopic neurosurgery problems with haemostasis due to poor access exist. We have developed a system which allows the delivery of a variety of haemostatic agents in a more efficacious manner. The system has been used successfully in endoscopic skull base surgery and endoscopic surgery within the parenchyma of the brain using tube systems. © Georg Thieme Verlag KG Stuttgart · New York.

  4. A multi-agent system for coordinating international shipping

    SciTech Connect

    Goldsmith, S.Y.; Phillips, L.R.; Spires, S.V.

    1998-05-01

    Moving commercial cargo across the US-Mexico border is currently a complex, paper-based, error-prone process that incurs expensive inspections and delays at several ports of entry in the Southwestern US. Improved information handling will dramatically reduce border dwell time, variation in delivery time, and inventories, and will give better control of the shipment process. The Border Trade Facilitation System (BTFS) is an agent-based collaborative work environment that assists geographically distributed commercial and government users with transshipment of goods across the US-Mexico border. Software agents mediate the creation, validation and secure sharing of shipment information and regulatory documentation over the Internet, using the World Wide Web to interface with human actors. Agents are organized into Agencies. Each agency represents a commercial or government agency. Agents perform four specific functions on behalf of their user organizations: (1) agents with domain knowledge elicit commercial and regulatory information from human specialists through forms presented via web browsers; (2) agents mediate information from forms with diverse otologies, copying invariant data from one form to another thereby eliminating the need for duplicate data entry; (3) cohorts of distributed agents coordinate the work flow among the various information providers and they monitor overall progress of the documentation and the location of the shipment to ensure that all regulatory requirements are met prior to arrival at the border; (4) agents provide status information to human actors and attempt to influence them when problems are predicted.

  5. Magnetic-resonance-based system for chemical agent screening

    NASA Astrophysics Data System (ADS)

    Kumar, Sankaran; Magnuson, Erik E.; Newman, David E.; Prado, Pablo J.; Lawton, Jess

    2003-09-01

    Quantum Magnetics is developing a system based on magnetic resonance (MR), combined with a proprietary technology, to screen for chemical agents in nonmetallic containers, without the need to open the container. It derives from the successful design and testing of a similar system for detecting liquid explosives. Preliminary measurements indicate that the system promises to quickly screen for many chemical agents and to offer an unambiguous hazard/safe result. The system will be designed to be portable and easy to operate, to need minimal human interpretation, and to be ideal for operation at checkpoints, government building, airports, and the like.

  6. Toward a systems- and control-oriented agent framework.

    PubMed

    Fregene, Kingsley; Kennedy, Diane C; Wang, David W L

    2005-10-01

    This paper develops a systems- and control-oriented intelligent agent framework called the hybrid intelligent control agent (HICA), as well as its composition into specific kinds of multiagent systems. HICA is essentially developed around a hybrid control system core so that knowledge-based planning and coordination can be integrated with verified hybrid control primitives to achieve the coordinated control of multiple multimode dynamical systems. The scheme is applied to the control of teams of unmanned air and ground vehicles engaged in a pursuit-evasion war game. Results are demonstrated in simulation.

  7. Lead(II) binding to the chelating agent D-penicillamine in aqueous solution.

    PubMed

    Sisombath, Natalie S; Jalilehvand, Farideh; Schell, Adam C; Wu, Qiao

    2014-12-01

    A spectroscopic investigation of the complexes formed between the Pb(II) ion and D-penicillamine (H2Pen), a chelating agent used in the treatment of lead poisoning, was carried out on two sets of alkaline aqueous solutions with CPb(II) ≈ 10 and 100 mM, varying the H2Pen/Pb(II) molar ratio (2.0, 3.0, 4.0, 10.0). Ultraviolet-visible (UV-vis) spectra of the 10 mM Pb(II) solutions consistently showed an absorption peak at 298 nm for S(-) → Pb(II) ligand-to-metal charge-transfer. The downfield (13)C NMR chemical shift for the penicillamine COO(-) group confirmed Pb(II) coordination. The (207)Pb NMR chemical shifts were confined to a narrow range between 1806 ppm and 1873 ppm for all Pb(II)-penicillamine solutions, indicating only small variations in the speciation, even in large penicillamine excess. Those chemical shifts are considerably deshielded, relative to the solid-state (207)Pb NMR isotropic chemical shift of 909 ppm obtained for crystalline penicillaminatolead(II) with Pb(S,N,O-Pen) coordination. The Pb LIII-edge extended X-ray absorption fine structure (EXAFS) spectra obtained for these solutions were well-modeled with two Pb-S and two Pb-(N/O) bonds with mean distances 2.64 ± 0.04 Å and 2.45 ± 0.04 Å, respectively. The combined spectroscopic results, reporting δ((207)Pb) ≈ 1870 ppm and λmax ≈ 298 nm for a Pb(II)S2NO site, are consistent with a dominating 1:2 lead(II):penicillamine complex with [Pb(S,N,O-Pen)(S-HnPen)](2-n) (n = 0-1) coordination in alkaline solutions, and provide useful structural information on how penicillamine can function as an antidote against lead toxicity in vivo.

  8. Modelling of Robotized Manufacturing Systems Using MultiAgent Formalism

    NASA Astrophysics Data System (ADS)

    Foit, K.; Gwiazda, A.; Banaś, W.

    2016-08-01

    The evolution of manufacturing systems has greatly accelerated due to development of sophisticated control systems. On top of determined, one way production flow the need of decision making has arisen as a result of growing product range that are manufactured simultaneously, using the same resources. On the other hand, the intelligent flow control could address the “bottleneck” problem caused by the machine failure. This sort of manufacturing systems uses advanced control algorithms that are introduced by the use of logic controllers. The complex algorithms used in the control systems requires to employ appropriate methods during the modelling process, like the agent-based one, which is the subject of this paper. The concept of an agent is derived from the object-based methodology of modelling, so it meets the requirements of representing the physical properties of the machines as well as the logical form of control systems. Each agent has a high level of autonomy and could be considered separately. The multi-agent system consists of minimum two agents that can interact and modify the environment, where they act. This may lead to the creation of self-organizing structure, what could be interesting feature during design and test of manufacturing system.

  9. An intelligent agent for optimal river-reservoir system management

    NASA Astrophysics Data System (ADS)

    Rieker, Jeffrey D.; Labadie, John W.

    2012-09-01

    A generalized software package is presented for developing an intelligent agent for stochastic optimization of complex river-reservoir system management and operations. Reinforcement learning is an approach to artificial intelligence for developing a decision-making agent that learns the best operational policies without the need for explicit probabilistic models of hydrologic system behavior. The agent learns these strategies experientially in a Markov decision process through observational interaction with the environment and simulation of the river-reservoir system using well-calibrated models. The graphical user interface for the reinforcement learning process controller includes numerous learning method options and dynamic displays for visualizing the adaptive behavior of the agent. As a case study, the generalized reinforcement learning software is applied to developing an intelligent agent for optimal management of water stored in the Truckee river-reservoir system of California and Nevada for the purpose of streamflow augmentation for water quality enhancement. The intelligent agent successfully learns long-term reservoir operational policies that specifically focus on mitigating water temperature extremes during persistent drought periods that jeopardize the survival of threatened and endangered fish species.

  10. Dynamic electronic institutions in agent oriented cloud robotic systems.

    PubMed

    Nagrath, Vineet; Morel, Olivier; Malik, Aamir; Saad, Naufal; Meriaudeau, Fabrice

    2015-01-01

    The dot-com bubble bursted in the year 2000 followed by a swift movement towards resource virtualization and cloud computing business model. Cloud computing emerged not as new form of computing or network technology but a mere remoulding of existing technologies to suit a new business model. Cloud robotics is understood as adaptation of cloud computing ideas for robotic applications. Current efforts in cloud robotics stress upon developing robots that utilize computing and service infrastructure of the cloud, without debating on the underlying business model. HTM5 is an OMG's MDA based Meta-model for agent oriented development of cloud robotic systems. The trade-view of HTM5 promotes peer-to-peer trade amongst software agents. HTM5 agents represent various cloud entities and implement their business logic on cloud interactions. Trade in a peer-to-peer cloud robotic system is based on relationships and contracts amongst several agent subsets. Electronic Institutions are associations of heterogeneous intelligent agents which interact with each other following predefined norms. In Dynamic Electronic Institutions, the process of formation, reformation and dissolution of institutions is automated leading to run time adaptations in groups of agents. DEIs in agent oriented cloud robotic ecosystems bring order and group intellect. This article presents DEI implementations through HTM5 methodology.

  11. Flexible solution for interoperable cloud healthcare systems.

    PubMed

    Vida, Mihaela Marcella; Lupşe, Oana Sorina; Stoicu-Tivadar, Lăcrămioara; Bernad, Elena

    2012-01-01

    It is extremely important for the healthcare domain to have a standardized communication because will improve the quality of information and in the end the resulting benefits will improve the quality of patients' life. The standards proposed to be used are: HL7 CDA and CCD. For a better access to the medical data a solution based on cloud computing (CC) is investigated. CC is a technology that supports flexibility, seamless care, and reduced costs of the medical act. To ensure interoperability between healthcare information systems a solution creating a Web Custom Control is presented. The control shows the database tables and fields used to configure the two standards. This control will facilitate the work of the medical staff and hospital administrators, because they can configure the local system easily and prepare it for communication with other systems. The resulted information will have a higher quality and will provide knowledge that will support better patient management and diagnosis.

  12. Robust Architectures for Complex Multi-Agent Heterogeneous Systems

    DTIC Science & Technology

    2014-07-23

    Bode-Like Integral for Stochastic Switched Systems with Applications in Networked Control Systems and Macroeconomics , In Proceedings of American...Raymarine has successfully implemented Adaptive Control on their Evolution Autopilot series for marine vessels.  Unmanned Dynamics multirotor solutions

  13. The Norm Implementation Problem in Normative Multi-Agent Systems

    NASA Astrophysics Data System (ADS)

    Grossi, D.; Gabbay, D.; van der Torre, L.

    The norm implementation problem consists in how to see to it that the agents in a system comply with the norms specified for that system by the system designer. It is part of the more general problem of how to synthesize or create norms for multi-agent systems, by, for example, highlighting the choice between regimentation and enforcement, or the punishment associated with a norm violation. In this paper we discuss how various ways to implement norms in a multi-agent system can be distinguished in a formal game-theoretic framework. In particular, we show how different types of norm implementation can all be uniformly specified and verified as types of transformations of extensive games. We introduce the notion of retarded preconditions to implement norms, and we illustrate the framework and the various ways to implement norms in the blocks world environment.

  14. Flocking of multi-agent systems with multiple groups

    NASA Astrophysics Data System (ADS)

    Jing, Gangshan; Zheng, Yuanshi; Wang, Long

    2014-12-01

    In this paper, we consider the flocking problem of multi-agent systems with multiple groups. First, some algorithms using local information are designed to divide the agents into any pre-assigned number of groups in fixed and switching heterogeneous networks, respectively. Based on algebraic graph theory and Barbalat's lemma, convergence criteria are established to ensure velocity alignment and cohesion of each subgroup as well as collision avoidance between any agents in the whole group. Second, an algorithm for homogeneous networks is studied. Simulation examples are finally presented to verify the effectiveness of our theoretical results.

  15. [In vitro tests of internal tooth whitening agents on colored solutions do not replace tests on teeth].

    PubMed

    Bäumler, Marc A; Schug, Jens; Schmidlin, PatrickR; Imfeld, Thomas

    2006-01-01

    Two in vitro tests for the assessment of whitening agents were evaluated. A simple, reproducible and cost-effective model using coloured solutions was compared to a tooth model. The following bleaching agents were investigated: 1) Sodium perborate tetrahydrate/30% H2O2, 2) sodium perborate tetrahydrate/3% H2O2, 3) thermocatalytic procedure with 30% H2O2 and 4) Opal-escence Endo. In the model using coloured solutions, the light absorption of the solutions was assessed one and 24 hours after application of the whitening agents. In discoloured teeth, whitening agents were placed in a simulated access cavity. In groups 1, 2, and 4, the agents were left in the cavity for three days, whereas in group 3 the substance was applied three times for 30 seconds. Bleaching processes were repeated three times. All bleaching agents proved effective in the model with coloured solutions, as well as in the tooth model. The effect was most pronounced after the first bleaching step. The results showed, however, that the simplified experiment with coloured solutions cannot replace the tooth model.

  16. Replication Based on Role Concept for Multi-Agent Systems

    NASA Astrophysics Data System (ADS)

    Bora, Sebnem; Dikenelli, Oguz

    Replication is widely used to improve fault tolerance in distributed and multi-agent systems. In this paper, we present a different point of view on replication in multi-agent systems. The approach we propose is based on role concept. We define a specific "fault tolerant role" which encapsulates all behaviors related to replication-based fault tolerance in this work. Our strategy is mainly focused on replicating instances of critical roles in the agent organization. However, while doing this, we simply transfer the critical role and the fault tolerant role to appropriate agents. Here, the fault tolerant role is responsible for coordination between replicated role instances (replicas). Moreover, our approach is flexible in terms of fault tolerance since it is possible to easily modify existing behaviors of the "fault tolerant" role, remove some of its behaviors, or include new behaviors to it due to its characteristic architecture.

  17. Review of systemization of the Tooele Chemical Agent Disposal Facility

    SciTech Connect

    1996-07-01

    In 1993, at Tooele Army Depot, Utah, the Army completed construction of the Tooele Chemical Agent Disposal Facility (TOCDF), the first complete facility for destruction of lethal unitary chemical agents and munitions to be built in the continental United States. The TOCDF will employ the Army`s baseline incineration system to destroy the depot`s increment of the nation`s aging unitary chemical stockpile. This book assesses Army changes and improvements to the TOCDF in response to recommendations contained in earlier reports of the committee. It assesses aspects of the facility`s readiness for safe agent handling and destruction operations, its agent monitoring system, and its site specific risk assessment.

  18. Surrounding control of nonlinear multi-agent systems with non-identical agents.

    PubMed

    Shoja, Shamisa; Baradarannia, Mahdi; Hashemzadeh, Farzad; Badamchizadeh, Mohammadali; Bagheri, Peyman

    2017-09-01

    In this paper, the surrounding control problem of a group of non-identical agents is considered, where a team of followers achieves an equidistant distributed formation to surround a team of moving leaders. An adaptive design method is presented for multi-agent systems where the dynamics of agents are supposed to be nonlinear with unknown parameters. First, an estimator for the center of the leaders is introduced. Then, two distributed adaptive controllers based on the estimated center are proposed for each follower. The stability and parameter convergence of the proposed protocols are shown by using algebraic graph theory and Lyapunov theory. Finally, a numerical example is provided to validate the theoretical results. Copyright © 2017 ISA. Published by Elsevier Ltd. All rights reserved.

  19. Biocatalytic Buffering System for Detoxification of Nerve Agents

    DTIC Science & Technology

    2005-11-30

    Organization (10 g of agent per m2), the concentration of agent in detergent and microemulsion systems, which typically consist of 1 to 10 vol... microemulsions and nanoemulsions. A portion of our efforts was focused towards assessing the use of biocatalytic pH control in these types of mediums...not accurately measure pH of the water core of micelles in a model water-in-oil microemulsion comprised of 13 vol % Tween 85, 8 vol % isopropanol

  20. Automated iodine monitor system. [for aqueous solutions

    NASA Technical Reports Server (NTRS)

    1973-01-01

    The feasibility of a direct spectrophotometric measurement of iodine in water was established. An iodine colorimeter, was built to demonstrate the practicality of this technique. The specificity of this method was verified when applied to an on-line system where a reference solution cannot be used, and a preliminary design is presented for an automated iodine measuring and controlling system meeting the desired specifications. An Automated iodine monitor/controller system based on this preliminary design was built, tested, and delivered to the Johnson Space Center.

  1. Flame Suppression Agent, System and Uses

    NASA Technical Reports Server (NTRS)

    Parrish, Clyde F. (Inventor)

    2013-01-01

    Aqueous droplets encapsulated in a flame retardant polymer are useful in suppressing combustion. Upon exposure to a flame, the encapsulated aqueous droplets rupture and vaporize, removing heat and displacing oxygen to retard the combustion process. The polymer encapsulant, through decomposition, may further add free radicals to the combustion atmosphere, thereby further retarding the combustion process. The encapsulated aqueous droplets may be used as a replacement to halon, water mist and dry powder flame suppression systems.

  2. Resilient Control System Execution Agent (ReCoSEA)

    SciTech Connect

    Craig G. Rieger; Kris Villez

    2012-08-01

    In an increasingly networked world, critical infrastructure systems suffer from two types of vulnerability. The first is the traditionally recognized problem of monitoring the systems for faults and failures, recognizing and analyzing data, and responding with real understanding to the problems of the system. Increasingly complex systems create the opportunity for single points of failure to cascade when inaccurate assessment of system health increases response time or leads to faulty analysis of the problems involved. A second problem involves vulnerability to cyber intrusion, in which bad actors can mask system deterioration or present false data about system status. A resilient system will protect stability, efficiency, and security. To ensure these three states, the system must react to changing conditions within the system with coordination: no one component of the system can be allowed to react to problems without real consideration of the effects of that action on other components within the system. Systems with multi-agent design typically have three layers of action, a management layer, a coordination layer, and an execution layer. A resilient multi-agent system will emphasize functions of the execution layer, which has the responsibility of initiating actions, monitoring, analyzing, and controlling its own processes, while feeding information back to the higher levels of management and coordination. The design concept of a resilient control system execution agent (ReCoSEA) grows out of these underpinnings, and through the use of computational intelligence techniques, this paper suggests an associated design methodology.

  3. Evaluating the STORE Reputation System in Multi-Agent Simulations

    NASA Astrophysics Data System (ADS)

    Andrulis, Jonas; Haller, Jochen; Weinhardt, Christof; Karabulut, Yuecel

    In recent global business environments, collaborations among organisations raise an increased demand for swift establishment. Such collaborations are formed between organisations entering Virtual Organizations (VOs), crossing geographic borders and frequently without prior experience of the other partner’s previous performance. In VOs, every participant risks engaging with partners who may exhibit unexpected fraudulent or otherwise untrusted behaviour. In order to cope with this risk, the STochastic REputation system (STORE) was designed to provide swift, automated decision support for selecting partner organisations in the early stages of the VO’s formation. The contribution of this paper first consists of a multi-agent simulation framework design and implementation to evaluate the STORE reputation system. This framework is able to simulate dynamic agent behaviour, agents hereby representing organisations, and to capture the business context of different VO application scenarios. A configuration of agent classes is a powerful tool to obtain not only well or badly performing agents for simulation scenarios, but also agents which are specialized in particular VO application domains or even malicious agents, attacking the VO community. The second contribution comprises of STORE’s evaluation in two simulation scenarios, set in the VO application domains of Collaborative Engineering and Ad-hoc Service provisioning. Besides the ability to clearly distinguish between agents of different classes according to their reputation, the results prove STORE’s ability to take an agent’s dynamic behaviour into account. The simulation results show, that STORE solves the difficult task of selecting the most trustworthy partner for a particular VO application domain from a set of honest agents that are specialized in a wide spread of VO application domains.

  4. Rational Solutions for the Fokas System

    NASA Astrophysics Data System (ADS)

    Rao, Ji-Guang; Wang, Li-Hong; Zhang, Yu; He, Jing-Song

    2015-12-01

    Fokas system is the simplest (2+1)-dimensional extension of the nonlinear Schrödinger equation (Eq. (2), Inverse Problems 10 (1994) L19-L22). By using the bilinear transformation method, general rational solutions for the Fokas system are given explicitly in terms of two order-N determinants τn (n = 0, 1) whose elements m(n)i,j (n = 0, 1; 1 ≤ i, j ≤ N) are involved with order-ni and order-nj derivatives. When N = 1, three kinds of rational solution, i.e., fundamental lump and fundamental rogue wave (RW) with n1 = 1, and higher-order rational solution with n1 ≥ 2, are illustrated by explicit formulas from τn (n = 0, 1) and pictures. The fundamental RW is a line RW possessing a line profile on (x, y)-plane, which arises from a constant background with at t ≪ 0 and then disappears into the constant background gradually at t ≫ 0. The fundamental lump is a traveling wave, which can preserve its profile during the propagation on (x, y)-plane. When N ≥ 2 and n1 = n2 = · · · = nN = 1, several specific multi-rational solutions are given graphically. Supported by the National Natural Science Foundation of China under Grant No. 11271210, the K.C. Wong Magna Fund in Ningbo University

  5. Citrate-Coated Silver Nanoparticles Interactions with Effluent Organic Matter: Influence of Capping Agent and Solution Conditions.

    PubMed

    Gutierrez, Leonardo; Aubry, Cyril; Cornejo, Mauricio; Croue, Jean-Philippe

    2015-08-18

    the importance of solution conditions and capping agents on the stability of AgNPs in solution. However, the characteristics of organics would play a crucial role in the fate and transport of these nano contaminants in urban wastewaters and natural water systems.

  6. Technology Review of Multi-Agent Systems and Tools

    DTIC Science & Technology

    2005-06-01

    machine of the agent, and the strategies associated with each state. B-10 Cable Language C++ and ADL Type System architecture Organization Logica ...URL Cable site Functional Description Cable is a generic system architecture developed by Logica as part of the GRACE Consortium. Cable can be

  7. Human sinonasal explant system for testing cytotoxicity of intranasal agents

    PubMed Central

    Lim, Jae H.; Davis, Greg E.; Rue, Tessa C.; Storm, Daniel R.

    2011-01-01

    BACKGROUND Intranasal agents play a critical role in the management of sinonasal disorders. There are ongoing efforts to develop new intranasal medications to combat sinonasal disease. Some intranasal agents, however, can have cytotoxic effects on human sinonasal tissue. In order to facilitate safe drug discovery, we developed a simple and reliable in vitro screening assay using human sinonasal explants to measure the cytotoxic profiles of intranasal agents. METHODS We obtained sinonasal tissues from several regions of the nasal cavity from 12 patients undergoing endoscopic sinonasal surgery. These tissues were cultured on polytetrafluoroethane membrane in serum free growth medium. We determined the biochemical properties of these explants by measuring extracellular lactate dehydrogenase (LDH) levels and performing histological analyses over a period of 1–2 weeks. We then examined the cytotoxic profiles of 13 intranasal agents by measuring extracellular LDH levels using the human sinonasal explant system. RESULTS Sinonasal explants exhibited a rapid reduction in extracellular LDH levels indicating stabilization in the culture environment within 2 days. Histological analysis showed maintenance of good cellular architecture for up to 2 weeks. The explants displayed intact epithelium and expressed βIII-tubulin and Ki-67. Of the 13 tested intranasal agents, 1% zinc sulfate, 5% zinc sulfate and Zicam application were cytotoxic. CONCLUSIONS Based on the unique biochemical properties of the human nasal explant culture system, we developed a simple and reliable in vitro screening assay to determine the cytotoxic profiles of various intranasal agents by examining extracellular LDH levels and histopathology. PMID:22170775

  8. Novel therapeutic agents in clinical development for systemic lupus erythematosus

    PubMed Central

    2013-01-01

    Conventional immunosuppressive therapies have radically transformed patient survival in systemic lupus erythematosus (SLE), but their use is associated with considerable toxicity and a substantial proportion of patients remain refractory to treatment. A more comprehensive understanding of the complexity of SLE immunopathogenesis has evolved over the past decade and has led to the testing of several biologic agents in clinical trials. There is a clear need for new therapeutic agents that overcome these issues, and biologic agents offer exciting prospects as future SLE therapies. An array of promising new therapies are currently emerging or are under development including B-cell depletion therapies, agents targeting B-cell survival factors, blockade of T-cell co-stimulation and anti-cytokine therapies, such as monoclonal antibodies against interleukin-6 and interferon-α. PMID:23642011

  9. A mobile agent approach for secure integrated medical information systems.

    PubMed

    Liu, Chia-Hui; Chung, Yu-Fang; Chiang, Te-Wei; Chen, Tzer-Shyong; Wang, Sheng-De

    2012-10-01

    Different patient-related information in medical organizations is the primary reference for medical personnel diagnosing, treating, and caring patients. With the rapid development of information technology, paper-based medical records have gradually been changed to electronic forms. However, different medical organizations present individual system specifications and data-saving formats so that the medical information of the same patient cannot be exchanged, shared, and securely accessed. In order not to largely change the present medical information systems as well as not to increase abundant costs, Virtual Integrated Medical-information Systems (VIMS) is proposed to assist various hospitals in information exchange. Furthermore, with Mobile Agent, the dispersed medical information can be securely integrated. It presents confidentiality, non-repudiation, source authentication, and integrity in network transmission. Virtual Integrated Medical-information Systems (VIMS) is a virtual electronic integration system combined with Mobile Agent technology. With the features of independence, adaptability, mobility, objectives, and autonomy, Mobile Agent is applied to overcome the problems from heterogeneous systems. With the features, the over-dispersed medical records can be integrated. Moreover, Mobile Agent can ensure the instantaneity and usability of medical records from which doctors can make the most appropriate evaluation and diagnoses. It will avoid the waste of medical resources, such as repetition medication, as well as become the reference of further consultation or health check. Not only can it improve the medical care quality, but it can be provided for medical research.

  10. Agent autonomy approach to probabilistic physics-of-failure modeling of complex dynamic systems with interacting failure mechanisms

    NASA Astrophysics Data System (ADS)

    Gromek, Katherine Emily

    A novel computational and inference framework of the physics-of-failure (PoF) reliability modeling for complex dynamic systems has been established in this research. The PoF-based reliability models are used to perform a real time simulation of system failure processes, so that the system level reliability modeling would constitute inferences from checking the status of component level reliability at any given time. The "agent autonomy" concept is applied as a solution method for the system-level probabilistic PoF-based (i.e. PPoF-based) modeling. This concept originated from artificial intelligence (AI) as a leading intelligent computational inference in modeling of multi agents systems (MAS). The concept of agent autonomy in the context of reliability modeling was first proposed by M. Azarkhail [1], where a fundamentally new idea of system representation by autonomous intelligent agents for the purpose of reliability modeling was introduced. Contribution of the current work lies in the further development of the agent anatomy concept, particularly the refined agent classification within the scope of the PoF-based system reliability modeling, new approaches to the learning and the autonomy properties of the intelligent agents, and modeling interacting failure mechanisms within the dynamic engineering system. The autonomous property of intelligent agents is defined as agent's ability to self-activate, deactivate or completely redefine their role in the analysis. This property of agents and the ability to model interacting failure mechanisms of the system elements makes the agent autonomy fundamentally different from all existing methods of probabilistic PoF-based reliability modeling. 1. Azarkhail, M., "Agent Autonomy Approach to Physics-Based Reliability Modeling of Structures and Mechanical Systems", PhD thesis, University of Maryland, College Park, 2007.

  11. Engineering large-scale agent-based systems with consensus

    NASA Technical Reports Server (NTRS)

    Bokma, A.; Slade, A.; Kerridge, S.; Johnson, K.

    1994-01-01

    The paper presents the consensus method for the development of large-scale agent-based systems. Systems can be developed as networks of knowledge based agents (KBA) which engage in a collaborative problem solving effort. The method provides a comprehensive and integrated approach to the development of this type of system. This includes a systematic analysis of user requirements as well as a structured approach to generating a system design which exhibits the desired functionality. There is a direct correspondence between system requirements and design components. The benefits of this approach are that requirements are traceable into design components and code thus facilitating verification. The use of the consensus method with two major test applications showed it to be successful and also provided valuable insight into problems typically associated with the development of large systems.

  12. Towards Time Automata and Multi-Agent Systems

    NASA Technical Reports Server (NTRS)

    Hutzler, G.; Klaudel, H.; Wang, D. Y.

    2004-01-01

    The design of reactive systems must comply with logical correctness (the system does what it is supposed to do) and timeliness (the system has to satisfy a set of temporal constraints) criteria. In this paper, we propose a global approach for the design of adaptive reactive systems, i.e., systems that dynamically adapt their architecture depending on the context. We use the timed automata formalism for the design of the agents' behavior. This allows evaluating beforehand the properties of the system (regarding logical correctness and timeliness), thanks to model-checking and simulation techniques. This model is enhanced with tools that we developed for the automatic generation of code, allowing to produce very quickly a running multi-agent prototype satisfying the properties of the model.

  13. Improving cold chain systems: Challenges and solutions.

    PubMed

    Ashok, Ashvin; Brison, Michael; LeTallec, Yann

    2017-04-19

    While a number of new vaccines have been rolled out across the developing world (with more vaccines in the pipeline), cold chain systems are struggling to efficiently support national immunization programs in ensuring the availability of safe and potent vaccines. This article reflects on the Clinton Health Access Initiative, Inc. (CHAI) experience working since 2010 with national immunization programs and partners to improve vaccines cold chains in 10 countries-Ethiopia, Nigeria, Kenya, Malawi, Tanzania, Uganda, Cameroon, Mozambique, Lesotho and India - to identify the root causes and solutions for three common issues limiting cold chain performance. Key recommendations include: Collectively, the solutions detailed in this article chart a path to substantially improving the performance of the cold chain. Combined with an enabling global and in-country environment, it is possible to eliminate cold chain issues as a substantial barrier to effective and full immunization coverage over the next few years. Copyright © 2017. Published by Elsevier Ltd.

  14. Lead(II) binding to the chelating agent d-penicillamine in aqueous solution

    DOE PAGES

    Sisombath, Natalie S.; Jalilehvand, Farideh; Schell, Adam C.; ...

    2014-11-11

    Here, a spectroscopic investigation of the complexes formed between the Pb(II) ion and d-penicillamine (H2Pen), a chelating agent used in the treatment of lead poisoning, was carried out on two sets of alkaline aqueous solutions with CPb(II) ≈ 10 and 100 mM, varying the H2Pen/Pb(II) molar ratio (2.0, 3.0, 4.0, 10.0). Ultraviolet–visible (UV-vis) spectra of the 10 mM Pb(II) solutions consistently showed an absorption peak at 298 nm for S– → Pb(II) ligand-to-metal charge-transfer. The downfield 13C NMR chemical shift for the penicillamine COO– group confirmed Pb(II) coordination. The 207Pb NMR chemical shifts were confined to a narrow range betweenmore » 1806 ppm and 1873 ppm for all Pb(II)-penicillamine solutions, indicating only small variations in the speciation, even in large penicillamine excess. Those chemical shifts are considerably deshielded, relative to the solid-state 207Pb NMR isotropic chemical shift of 909 ppm obtained for crystalline penicillaminatolead(II) with Pb(S,N,O-Pen) coordination. The Pb LIII-edge extended X-ray absorption fine structure (EXAFS) spectra obtained for these solutions were well-modeled with two Pb–S and two Pb-(N/O) bonds with mean distances 2.64 ± 0.04 Å and 2.45 ± 0.04 Å, respectively. The combined spectroscopic results, reporting δ(207Pb) ≈ 1870 ppm and λmax ≈ 298 nm for a PbIIS2NO site, are consistent with a dominating 1:2 lead(II):penicillamine complex with [Pb(S,N,O-Pen)(S-HnPen)]2–n (n = 0–1) coordination in alkaline solutions, and provide useful structural information on how penicillamine can function as an antidote against lead toxicity in vivo.« less

  15. Lead(II) Binding to the Chelating Agent d-Penicillamine in Aqueous Solution

    PubMed Central

    2015-01-01

    A spectroscopic investigation of the complexes formed between the Pb(II) ion and d-penicillamine (H2Pen), a chelating agent used in the treatment of lead poisoning, was carried out on two sets of alkaline aqueous solutions with CPb(II) ≈ 10 and 100 mM, varying the H2Pen/Pb(II) molar ratio (2.0, 3.0, 4.0, 10.0). Ultraviolet–visible (UV-vis) spectra of the 10 mM Pb(II) solutions consistently showed an absorption peak at 298 nm for S– → Pb(II) ligand-to-metal charge-transfer. The downfield 13C NMR chemical shift for the penicillamine COO– group confirmed Pb(II) coordination. The 207Pb NMR chemical shifts were confined to a narrow range between 1806 ppm and 1873 ppm for all Pb(II)-penicillamine solutions, indicating only small variations in the speciation, even in large penicillamine excess. Those chemical shifts are considerably deshielded, relative to the solid-state 207Pb NMR isotropic chemical shift of 909 ppm obtained for crystalline penicillaminatolead(II) with Pb(S,N,O-Pen) coordination. The Pb LIII-edge extended X-ray absorption fine structure (EXAFS) spectra obtained for these solutions were well-modeled with two Pb–S and two Pb-(N/O) bonds with mean distances 2.64 ± 0.04 Å and 2.45 ± 0.04 Å, respectively. The combined spectroscopic results, reporting δ(207Pb) ≈ 1870 ppm and λmax ≈ 298 nm for a PbIIS2NO site, are consistent with a dominating 1:2 lead(II):penicillamine complex with [Pb(S,N,O-Pen)(S-HnPen)]2–n (n = 0–1) coordination in alkaline solutions, and provide useful structural information on how penicillamine can function as an antidote against lead toxicity in vivo. PMID:25385465

  16. Lead(II) binding to the chelating agent d-penicillamine in aqueous solution

    SciTech Connect

    Sisombath, Natalie S.; Jalilehvand, Farideh; Schell, Adam C.; Wu, Qiao

    2014-11-11

    Here, a spectroscopic investigation of the complexes formed between the Pb(II) ion and d-penicillamine (H2Pen), a chelating agent used in the treatment of lead poisoning, was carried out on two sets of alkaline aqueous solutions with CPb(II) ≈ 10 and 100 mM, varying the H2Pen/Pb(II) molar ratio (2.0, 3.0, 4.0, 10.0). Ultraviolet–visible (UV-vis) spectra of the 10 mM Pb(II) solutions consistently showed an absorption peak at 298 nm for S → Pb(II) ligand-to-metal charge-transfer. The downfield 13C NMR chemical shift for the penicillamine COO group confirmed Pb(II) coordination. The 207Pb NMR chemical shifts were confined to a narrow range between 1806 ppm and 1873 ppm for all Pb(II)-penicillamine solutions, indicating only small variations in the speciation, even in large penicillamine excess. Those chemical shifts are considerably deshielded, relative to the solid-state 207Pb NMR isotropic chemical shift of 909 ppm obtained for crystalline penicillaminatolead(II) with Pb(S,N,O-Pen) coordination. The Pb LIII-edge extended X-ray absorption fine structure (EXAFS) spectra obtained for these solutions were well-modeled with two Pb–S and two Pb-(N/O) bonds with mean distances 2.64 ± 0.04 Å and 2.45 ± 0.04 Å, respectively. The combined spectroscopic results, reporting δ(207Pb) ≈ 1870 ppm and λmax ≈ 298 nm for a PbIIS2NO site, are consistent with a dominating 1:2 lead(II):penicillamine complex with [Pb(S,N,O-Pen)(S-HnPen)]2–n (n = 0–1) coordination in alkaline solutions, and provide useful structural information on how penicillamine can function as an antidote against lead toxicity in vivo.

  17. Microfluidic System for Solution Array Based Bioassays

    SciTech Connect

    Dougherty, G M; Tok, J B; Pannu, S S; Rose, K A

    2006-02-10

    The objective of this project is to demonstrate new enabling technology for multiplex biodetection systems that are flexible, miniaturizable, highly automated, low cost, and high performance. It builds on prior successes at LLNL with particle-based solution arrays, such as those used in the Autonomous Pathogen Detection System (APDS) successfully field deployed to multiple locations nationwide. We report the development of a multiplex solution array immunoassay based upon engineered metallic nanorod particles. Nanobarcodes{reg_sign} particles are fabricated by sequential electrodeposition of dissimilar metals within porous alumina templates, yielding optically encoded striping patterns that can be read using standard laboratory microscope optics and PC-based image processing software. The addition of self-assembled monolayer (SAM) coatings and target-specific antibodies allows each encoded class of nanorod particles to be directed against a different antigen target. A prototype assay panel directed against bacterial, viral, and soluble protein targets demonstrates simultaneous detection at sensitivities comparable to state of the art immunoassays, with minimal cross-reactivity. Studies have been performed to characterize the colloidal properties (zeta potential) of the suspended nanorod particles as a function of pH, the ionic strength of the suspending solution, and surface functionalization state. Additional studies have produced means for the non-contact manipulation of the particles, including the insertion of magnetic nickel stripes within the encoding pattern, and control via externally applied electromagnetic fields. Using the results of these studies, the novel Nanobarcodes{reg_sign} based assay was implemented in a prototype automated system with the sample processing functions and optical readout performed on a microfluidic card. The unique physical properties of the nanorod particles enable the development of integrated microfluidic systems for

  18. The Role of Intelligent Agents in Advanced Information Systems

    NASA Technical Reports Server (NTRS)

    Kerschberg, Larry

    1999-01-01

    In this presentation we review the current ongoing research within George Mason University's (GMU) Center for Information Systems Integration and Evolution (CISE). We define characteristics of advanced information systems, discuss a family of agents for such systems, and show how GMU's Domain modeling tools and techniques can be used to define a product line Architecture for configuring NASA missions. These concepts can be used to define Advanced Engineering Environments such as those envisioned for NASA's new initiative for intelligent design and synthesis environments.

  19. The Role of Intelligent Agents in Advanced Information Systems

    NASA Technical Reports Server (NTRS)

    Kerschberg, Larry

    1999-01-01

    In this presentation we review the current ongoing research within George Mason University's (GMU) Center for Information Systems Integration and Evolution (CISE). We define characteristics of advanced information systems, discuss a family of agents for such systems, and show how GMU's Domain modeling tools and techniques can be used to define a product line Architecture for configuring NASA missions. These concepts can be used to define Advanced Engineering Environments such as those envisioned for NASA's new initiative for intelligent design and synthesis environments.

  20. Model of load balancing using reliable algorithm with multi-agent system

    NASA Astrophysics Data System (ADS)

    Afriansyah, M. F.; Somantri, M.; Riyadi, M. A.

    2017-04-01

    Massive technology development is linear with the growth of internet users which increase network traffic activity. It also increases load of the system. The usage of reliable algorithm and mobile agent in distributed load balancing is a viable solution to handle the load issue on a large-scale system. Mobile agent works to collect resource information and can migrate according to given task. We propose reliable load balancing algorithm using least time first byte (LFB) combined with information from the mobile agent. In system overview, the methodology consisted of defining identification system, specification requirements, network topology and design system infrastructure. The simulation method for simulated system was using 1800 request for 10 s from the user to the server and taking the data for analysis. Software simulation was based on Apache Jmeter by observing response time and reliability of each server and then compared it with existing method. Results of performed simulation show that the LFB method with mobile agent can perform load balancing with efficient systems to all backend server without bottleneck, low risk of server overload, and reliable.

  1. Intelligent multi-agent coordination system for advanced manufacturing

    NASA Astrophysics Data System (ADS)

    Maturana, Francisco P.; Balasubramanian, Sivaram; Norrie, Douglas H.

    1997-12-01

    Global competition and rapidly changing customer requirements are forcing major changes in the production styles and configuration of manufacturing organizations. Agent-based systems are showing considerable potential as a new paradigm for agile manufacturing systems. With this approach, centralized and sequential manufacturing planning, scheduling, and control systems may be replaced by distributed intelligent systems to facilitate flexible and rapid response to changing production styles and variations in product requirements. In this paper, the characteristics and components of such a multi-agent architecture for advanced manufacturing are described. This architecture addresses agility in terms of the ability of the manufacturing system to solve manufacturing tasks using virtual enterprise mechanisms while maintaining concurrent information processing and control.

  2. Product Distribution Theory for Control of Multi-Agent Systems

    NASA Technical Reports Server (NTRS)

    Lee, Chia Fan; Wolpert, David H.

    2004-01-01

    Product Distribution (PD) theory is a new framework for controlling Multi-Agent Systems (MAS's). First we review one motivation of PD theory, as the information-theoretic extension of conventional full-rationality game theory to the case of bounded rational agents. In this extension the equilibrium of the game is the optimizer of a Lagrangian of the (probability distribution of) the joint stare of the agents. Accordingly we can consider a team game in which the shared utility is a performance measure of the behavior of the MAS. For such a scenario the game is at equilibrium - the Lagrangian is optimized - when the joint distribution of the agents optimizes the system's expected performance. One common way to find that equilibrium is to have each agent run a reinforcement learning algorithm. Here we investigate the alternative of exploiting PD theory to run gradient descent on the Lagrangian. We present computer experiments validating some of the predictions of PD theory for how best to do that gradient descent. We also demonstrate how PD theory can improve performance even when we are not allowed to rerun the MAS from different initial conditions, a requirement implicit in some previous work.

  3. A Multi Agent System for Flow-Based Intrusion Detection

    DTIC Science & Technology

    2013-03-01

    training and online testing execution paths . . . . . . . . . . 106 3.13 Add and Del Mutations...The basis of a centralized approach is the same as that of online rating systems employed for shopping [147]. Following an interaction, a witness...allow the centralized evaluator to determine the resulting reputation. This reputation can then be used as a criterion by which other agents or online

  4. Agents.

    PubMed

    Chambers, David W

    2002-01-01

    Although health care is inherently an economic activity, it is inadequately described as a market process. An alternative, grounded in organizational economic theory, is to view professionals and many others as agents, contracted to advance the best interests of their principals (patients). This view untangles some of the ethical conflicts in dentistry. It also helps identify major controllable costs in dentistry and suggests that dentists can act as a group to increase or decrease agency costs, primarily by controlling the bad actors who damage the value of all dentists.

  5. The potential for solubilizing agents to enhance the remediation of hydrophobic organic solutes in soil-water suspensions. [Quarterly report

    SciTech Connect

    Laha, S.; Liu, Z.; Edwards, D.; Luthy, R.G.

    1991-02-01

    This paper discusses the feasibility for use of surfactant solubilizing agents to enhance the solubility and the rate of microbial degradation of hydrophobic organic solutes in soil-water suspensions. Hydrophobic organic contaminants are strongly sorbed to soil or sediment material, and as a consequence the rate of microbial degradation may depend greatly on the desorption of the sorbed-phase contaminant and the accessibility of the contaminant to soil microorganisms. Chemical solubilizing agents may enhance the rate of hydrophobic organic solute degradation by increasing the rate of solute desorption from soil and the extent of solute partitioning to the aqueous phase. The presentation will review on-going research on: surfactant solubilization of polycyclic aromatic hydrocarbon (PAH) compounds in clean water, and in soil-water suspensions; and experiments to assess if the addition of surfactant to soil-water suspension results in faster rate of mineralization of PAH compounds in soil.

  6. The potential for solubilizing agents to enhance the remediation of hydrophobic organic solutes in soil-water suspensions

    SciTech Connect

    Laha, S.; Liu, Z.; Edwards, D.; Luthy, R.G.

    1991-02-01

    This paper discusses the feasibility for use of surfactant solubilizing agents to enhance the solubility and the rate of microbial degradation of hydrophobic organic solutes in soil-water suspensions. Hydrophobic organic contaminants are strongly sorbed to soil or sediment material, and as a consequence the rate of microbial degradation may depend greatly on the desorption of the sorbed-phase contaminant and the accessibility of the contaminant to soil microorganisms. Chemical solubilizing agents may enhance the rate of hydrophobic organic solute degradation by increasing the rate of solute desorption from soil and the extent of solute partitioning to the aqueous phase. The presentation will review on-going research on: surfactant solubilization of polycyclic aromatic hydrocarbon (PAH) compounds in clean water, and in soil-water suspensions; and experiments to assess if the addition of surfactant to soil-water suspension results in faster rate of mineralization of PAH compounds in soil.

  7. A multi-agent system for monitoring patient flow.

    PubMed

    Rosati, Samanta; Tralli, Augusta; Balestra, Gabriella

    2013-01-01

    Patient flow within a healthcare facility may follow different and, sometimes, complicated paths. Each path phase is associated with the documentation of the activities carried out during it and may require the consultation of clinical guidelines, medical literature and the use of specific software and decision aid systems. In this study we present the design of a Patient Flow Management System (PFMS) based on Multi Agent Systems (MAS) methodology. System requirements were identified by means of process modeling tools and a MAS consisting of six agents was designed and is under construction. Its main goal is to support both the medical staff during the health care process and the hospital managers in assuring that all the required documentation is completed and available. Moreover, such a tool can be used for the assessment and comparison of different clinical pathways, in order to identify possible improvementsand the optimum patient flow.

  8. System Configured For Applying Multiple Modifying Agents To A Substrate.

    DOEpatents

    Propp, W. Alan; Argyle, Mark D.; Janikowski, Stuart K.; Fox, Robert V.; Toth, William J.; Ginosar, Daniel M.; Allen, Charles A.; Miller, David L.

    2005-11-08

    The present invention is related to the modifying of substrates with multiple modifying agents in a single continuous system. At least two processing chambers are configured for modifying the substrate in a continuous feed system. The processing chambers can be substantially isolated from one another by interstitial seals. Additionally, the two processing chambers can be substantially isolated from the surrounding atmosphere by end seals. Optionally, expansion chambers can be used to separate the seals from the processing chambers.

  9. System configured for applying multiple modifying agents to a substrate

    DOEpatents

    Propp, W. Alan; Argyle, Mark D.; Janikowski, Stuart K.; Fox, Robert V.; Toth, William J.; Ginosar, Daniel M.; Allen, Charles A.; Miller, David L.

    2003-11-25

    The present invention is related to the modifying of substrates with multiple modifying agents in a single continuous system. At least two processing chambers are configured for modifying the substrate in a continuous feed system. The processing chambers can be substantially isolated from one another by interstitial seals. Additionally, the two processing chambers can be substantially isolated from the surrounding atmosphere by end seals. Optionally, expansion chambers can be used to separate the seals from the processing chambers.

  10. Redefining the properties of an osmotic agent in an intestinal-specific preservation solution

    PubMed Central

    Schlachter, Kimberly; Kokotilo, Matthew S; Carter, Jodi; Thiesen, Aducio; Ochs, Angela; Khadaroo, Rachel G; Churchill, Thomas A

    2010-01-01

    AIM: To investigate the effects of dextrans of various molecular weights (Mw) during a 12 h cold storage time-course on energetics, histology and mucosal infiltration of fluorescein isothiocyanate (FITC)-dextran. METHODS: Rodent intestines were isolated and received a standard University of Wisconsin vascular flush followed by intraluminal administration of a nutrient-rich preservation solution containing dextrans of varying Mw: Group D1, 73 kdal; Group D2, 276 kdal; Group D3, 534 kdal; Group D4, 1185 kdal; Group D5, 2400 kdal. RESULTS: Using FITC-labeled dextrans, fluorescent micrographs demonstrated varying degrees of mucosal infiltration; lower Mw (groups D1-D3: 73-534 kdal) dextrans penetrated the mucosa as early as 2 h, whereas the largest dextran (D5: 2400 kdal) remained captive within the lumen and exhibited no permeability even after 12 h. After 12 h, median injury grades ranged from 6.5 to 7.5 in groups D1-D4 (73-1185 kdal) representing injury of the regenerative cryptal regions and submucosa; this was in contrast to group D5 (2400 kdal) which exhibited villus denudation (with intact crypts) corresponding to a median injury grade of 4 (P < 0.05). Analysis of tissue energetics reflected a strong positive correlation between Mw and adenosine triphosphate (r2 = 0.809), total adenylates (r2 = 0.865) and energy charge (r2 = 0.667). CONCLUSION: Our data indicate that dextrans of Mw > 2400 kdal act as true impermeant agents during 12 h ischemic storage when incorporated into an intraluminal preservation solution. PMID:21128319

  11. Challenges and solutions for clinical development of new antibacterial agents: results of a survey among pharmaceutical industry professionals.

    PubMed

    Bettiol, Esther; Wetherington, Jeffrey D; Schmitt, Nicola; Harbarth, Stephan

    2015-07-01

    As the number of antibacterial medicines in the pipeline remains low, we anonymously surveyed pharmaceutical industry professionals on challenges and solutions for clinical development of these agents. Challenges were reported primarily as financial and regulatory. For multidrug-resistant organisms, there are needs for rapid diagnostic tests, new regulatory guidance, and adaptation of endpoints/trial designs. Regulators and public/private initiatives are addressing these challenges to help ensure that proposed solutions have the support of all involved stakeholders.

  12. A Multi-Agent Design for Power Distribution Systems Automation

    NASA Astrophysics Data System (ADS)

    Ghorbani, M. Jawad

    A new Multi Agent System (MAS) design for fault location, isolation and restoration in power distribution systems is presented. In proposed approach, when there is a fault in the Power Distribution System (PDS), MAS quickly isolates the fault and restores the service to fault-free zones. Hierarchical coordination strategy is introduced to manage the agents which integrate the advantages of both centralized and decentralized coordination strategies. In this framework, Zone Agent (ZA) locate and isolate the fault based on the locally available information and assist the Feeder Agent (FA) for reconfiguration and restoration. FA can solve the restoration problem using the existing algorithms for the 0-1 Knapsack problem. A novel Q-learning mechanism is also introduced to support the FAs in decision making for restoration. Also a distributed MAS-Based Load Shedding (LS) technique has been used to supply as many of higher priority customers as possible, in case there is more demand than generation. The design is illustrated by the use of simulation case studies for fault location, isolation and restoration on West Virginia Super Circuit (WVSC) and hardware implementation for fault location and isolation in a laboratory platform. The results from the case studies indicate the performance of proposed MAS designs.

  13. Influence of precipitating agents on thermodynamic parameters of protein crystallization solutions.

    PubMed

    Stavros, Philemon; Saridakis, Emmanuel; Nounesis, George

    2016-09-01

    X-ray crystallography is the most powerful method for determining three-dimensional structures of proteins to (near-)atomic resolution, but protein crystallization is a poorly explained and often intractable phenomenon. Differential Scanning Calorimetry was used to measure the thermodynamic parameters (ΔG, ΔH, ΔS) of temperature-driven unfolding of two globular proteins, lysozyme, and ribonuclease A, in various salt solutions. The mixtures were categorized into those that were conducive to crystallization of the protein and those that were not. It was found that even fairly low salt concentrations had very large effects on thermodynamic parameters. High concentrations of salts conducive to crystallization stabilized the native folded forms of proteins, whereas high concentrations of salts that did not crystallize them tended to destabilize them. Considering the ΔH and TΔS contributions to the ΔG of unfolding separately, high concentrations of crystallizing salts were found to enthalpically stabilize and entropically destabilize the protein, and vice-versa for the noncrystallizing salts. These observations suggest an explanation, in terms of protein stability and entropy of hydration, of why some salts are good crystallization agents for a given protein and others are not. This in turn provides theoretical insight into the process of protein crystallization, suggesting ways of predicting and controlling it. © 2016 Wiley Periodicals, Inc. Biopolymers 105: 642-652, 2016.

  14. An agent-based microsimulation of critical infrastructure systems

    SciTech Connect

    BARTON,DIANNE C.; STAMBER,KEVIN L.

    2000-03-29

    US infrastructures provide essential services that support the economic prosperity and quality of life. Today, the latest threat to these infrastructures is the increasing complexity and interconnectedness of the system. On balance, added connectivity will improve economic efficiency; however, increased coupling could also result in situations where a disturbance in an isolated infrastructure unexpectedly cascades across diverse infrastructures. An understanding of the behavior of complex systems can be critical to understanding and predicting infrastructure responses to unexpected perturbation. Sandia National Laboratories has developed an agent-based model of critical US infrastructures using time-dependent Monte Carlo methods and a genetic algorithm learning classifier system to control decision making. The model is currently under development and contains agents that represent the several areas within the interconnected infrastructures, including electric power and fuel supply. Previous work shows that agent-based simulations models have the potential to improve the accuracy of complex system forecasting and to provide new insights into the factors that are the primary drivers of emergent behaviors in interdependent systems. Simulation results can be examined both computationally and analytically, offering new ways of theorizing about the impact of perturbations to an infrastructure network.

  15. Designing of Roaming Protocol for Bluetooth Equipped Multi Agent Systems

    NASA Astrophysics Data System (ADS)

    Subhan, Fazli; Hasbullah, Halabi B.

    Bluetooth is an established standard for low cost, low power, wireless personal area network. Currently, Bluetooth does not support any roaming protocol in which handoff occurs dynamically when a Bluetooth device is moving out of the piconet. If a device is losing its connection to the master device, no provision is made to transfer it to another master. Handoff is not possible in a piconet, as in order to stay within the network, a slave would have to keep the same master. So, by definition intra-handoff is not possible within a piconet. This research mainly focuses on Bluetooth technology and designing a roaming protocol for Bluetooth equipped multi agent systems. A mathematical model is derived for an agent. The idea behind the mathematical model is to know when to initiate the roaming process for an agent. A desired trajectory for the agent is calculated using its x and y coordinates system, and is simulated in SIMULINK. Various roaming techniques are also studied and discussed. The advantage of designing a roaming protocol is to ensure the Bluetooth enabled roaming devices can freely move inside the network coverage without losing its connection or break of service in case of changing the base stations.

  16. Systemic anti-microbial agents used in periodontal therapy

    PubMed Central

    Patil, Vishakha; Mali, Rohini; Mali, Amita

    2013-01-01

    Periodontitis is an infectious disease with marked inflammatory response, leading to destruction of underlying tissues. The aim of periodontal therapy is to eradicate the pathogens associated with the disease and attain periodontal health. This is achieved by non-surgical and surgical therapy; however, mechanical debridement and topical application of antiseptics may not be helpful in all cases. In such cases, adjunctive systemic antibiotic therapy remains the treatment of choice. It can reach micro-organisms at the base of the deep periodontal pockets and furcation areas via serum, and also affect organisms residing within gingival epithelium and connective tissue. Before advising any anti-microbial agent, it is necessary to have knowledge of that agent. The aim of this review article is to provide basic details of each systemic anti-microbial agent used in periodontal therapy. The points discussed are its mode of action, susceptible periodontal pathogens, dosage, its use in treatment of periodontal disease, and mechanism of bacterial resistance to each anti-microbial agent. It might be of some help while prescribing these drugs. PMID:23869120

  17. Adaptive, Distributed Control of Constrained Multi-Agent Systems

    NASA Technical Reports Server (NTRS)

    Bieniawski, Stefan; Wolpert, David H.

    2004-01-01

    Product Distribution (PO) theory was recently developed as a broad framework for analyzing and optimizing distributed systems. Here we demonstrate its use for adaptive distributed control of Multi-Agent Systems (MASS), i.e., for distributed stochastic optimization using MAS s. First we review one motivation of PD theory, as the information-theoretic extension of conventional full-rationality game theory to the case of bounded rational agents. In this extension the equilibrium of the game is the optimizer of a Lagrangian of the (Probability dist&&on on the joint state of the agents. When the game in question is a team game with constraints, that equilibrium optimizes the expected value of the team game utility, subject to those constraints. One common way to find that equilibrium is to have each agent run a Reinforcement Learning (E) algorithm. PD theory reveals this to be a particular type of search algorithm for minimizing the Lagrangian. Typically that algorithm i s quite inefficient. A more principled alternative is to use a variant of Newton's method to minimize the Lagrangian. Here we compare this alternative to RL-based search in three sets of computer experiments. These are the N Queen s problem and bin-packing problem from the optimization literature, and the Bar problem from the distributed RL literature. Our results confirm that the PD-theory-based approach outperforms the RL-based scheme in all three domains.

  18. Fault-tolerant cooperative tasking for multi-agent systems

    NASA Astrophysics Data System (ADS)

    Karimadini, Mohammad; Lin, Hai

    2011-12-01

    A natural way for cooperative tasking in multi-agent systems is through a top-down design by decomposing a global task into subtasks for each individual agent such that the accomplishments of these subtasks will guarantee the achievement of the global task. In our previous works [Karimadini, M., and Lin, H. (2011c), 'Guaranteed Global Performance Through Local Coordinations', Automatica, 47, 890--898; Karimadini, M., and Lin, H. (2011a), 'Cooperative Tasking for Deterministic Specification Automata', submitted for publication, online available at: http://arxiv.org/abs/1101.2002], we presented necessary and sufficient conditions on the decomposability of a global task automaton between cooperative agents. As a follow-up work, this article deals with the robustness issues of the proposed top-down design approach with respect to event failures in the multi-agent systems. The main concern under event failure is whether a previously decomposable task can still be achieved collectively by the agents, and if not, we would like to investigate that under what conditions the global task could be robustly accomplished. This is actually the fault-tolerance issue of the top-down design, and the results provide designers with hints on which events are fragile with respect to failures, and whether redundancies are needed. The main objective of this article is to identify necessary and sufficient conditions on failed events under which a decomposable global task can still be achieved successfully. For such a purpose, a notion called passivity is introduced to characterise the type of event failures. The passivity is found to reflect the redundancy of communication links over shared events, based on which necessary and sufficient conditions for the reliability of cooperative tasking under event failures are derived, followed by illustrative examples and remarks for the derived conditions.

  19. From actors to agents in socio-ecological systems models

    PubMed Central

    Rounsevell, M. D. A.; Robinson, D. T.; Murray-Rust, D.

    2012-01-01

    The ecosystem service concept has emphasized the role of people within socio-ecological systems (SESs). In this paper, we review and discuss alternative ways of representing people, their behaviour and decision-making processes in SES models using an agent-based modelling (ABM) approach. We also explore how ABM can be empirically grounded using information from social survey. The capacity for ABM to be generalized beyond case studies represents a crucial next step in modelling SESs, although this comes with considerable intellectual challenges. We propose the notion of human functional types, as an analogy of plant functional types, to support the expansion (scaling) of ABM to larger areas. The expansion of scope also implies the need to represent institutional agents in SES models in order to account for alternative governance structures and policy feedbacks. Further development in the coupling of human-environment systems would contribute considerably to better application and use of the ecosystem service concept. PMID:22144388

  20. Team Formation in Partially Observable Multi-Agent Systems

    NASA Technical Reports Server (NTRS)

    Agogino, Adrian K.; Tumer, Kagan

    2004-01-01

    Sets of multi-agent teams often need to maximize a global utility rating the performance of the entire system where a team cannot fully observe other teams agents. Such limited observability hinders team-members trying to pursue their team utilities to take actions that also help maximize the global utility. In this article, we show how team utilities can be used in partially observable systems. Furthermore, we show how team sizes can be manipulated to provide the best compromise between having easy to learn team utilities and having them aligned with the global utility, The results show that optimally sized teams in a partially observable environments outperform one team in a fully observable environment, by up to 30%.

  1. Agent-based models in translational systems biology

    PubMed Central

    An, Gary; Mi, Qi; Dutta-Moscato, Joyeeta; Vodovotz, Yoram

    2013-01-01

    Effective translational methodologies for knowledge representation are needed in order to make strides against the constellation of diseases that affect the world today. These diseases are defined by their mechanistic complexity, redundancy, and nonlinearity. Translational systems biology aims to harness the power of computational simulation to streamline drug/device design, simulate clinical trials, and eventually to predict the effects of drugs on individuals. The ability of agent-based modeling to encompass multiple scales of biological process as well as spatial considerations, coupled with an intuitive modeling paradigm, suggests that this modeling framework is well suited for translational systems biology. This review describes agent-based modeling and gives examples of its translational applications in the context of acute inflammation and wound healing. PMID:20835989

  2. A mobile biosafety microanalysis system for infectious agents.

    PubMed

    Beniac, Daniel R; Hiebert, Shannon L; Siemens, Christine G; Corbett, Cindi R; Booth, Tim F

    2015-03-30

    Biological threats posed by pathogens such as Ebola virus must be quickly diagnosed, while protecting the safety of personnel. Scanning electron microscopy and microanalysis requires minimal specimen preparation and can help to identify hazardous agents or substances. Here we report a compact biosafety system for rapid imaging and elemental analysis of specimens, including powders, viruses and bacteria, which is easily transportable to the site of an incident.

  3. Beat frequency ultrasonic microsphere contrast agent detection system

    NASA Technical Reports Server (NTRS)

    Pretlow, III, Robert A. (Inventor); Yost, William T. (Inventor); Cantrell, Jr., John H. (Inventor)

    1997-01-01

    A system for and method of detecting and measuring concentrations of an ultrasonically-reflective microsphere contrast agent involving detecting non-linear sum and difference beat frequencies produced by the microspheres when two impinging signals with non-identical frequencies are combined by mixing. These beat frequencies can be used for a variety of applications such as detecting the presence of and measuring the flow rates of biological fluids and industrial liquids, including determining the concentration level of microspheres in the myocardium.

  4. A mobile biosafety microanalysis system for infectious agents

    PubMed Central

    Beniac, Daniel R.; Hiebert, Shannon L.; Siemens, Christine G.; Corbett, Cindi R.; Booth, Tim F.

    2015-01-01

    Biological threats posed by pathogens such as Ebola virus must be quickly diagnosed, while protecting the safety of personnel. Scanning electron microscopy and microanalysis requires minimal specimen preparation and can help to identify hazardous agents or substances. Here we report a compact biosafety system for rapid imaging and elemental analysis of specimens, including powders, viruses and bacteria, which is easily transportable to the site of an incident. PMID:25820944

  5. Broadcast Based Control of Multi-Agent Systems for Consensus

    DTIC Science & Technology

    2010-12-01

    Bangalore, India Report Documentation Page Form ApprovedOMB No. 0704-0188 Public reporting burden for the collection of information is estimated to average...Engineering,Bangalore 560-012, India ,IN,560-012 8. PERFORMING ORGANIZATION REPORT NUMBER N/A 9. SPONSORING/MONITORING AGENCY NAME(S) AND ADDRESS(ES...Aerospace Engineering (ICEAE2009), Bangalore, India , May 2009, pp. 1327-1336. K. Das and D. Ghose: Positional consensus in multi-agent systems using

  6. Beat frequency ultrasonic microsphere contrast agent detection system

    NASA Technical Reports Server (NTRS)

    Pretlow, Robert A., III (Inventor); Yost, William T. (Inventor); Cantrell, John H., Jr. (Inventor)

    1995-01-01

    A system for and method of detecting and measuring concentrations of an ultrasonically-reflective microsphere contrast agent involving detecting non-linear sum and difference beat frequencies produced by the microspheres when two impinging signals with non-identical frequencies are combined by mixing. These beat frequencies can be used for a variety of applications such as detecting the presence of and measuring the flow rates of biological fluids and industrial liquids, including determining the concentration level of microspheres in the myocardium.

  7. Designing Agent Collectives For Systems With Markovian Dynamics

    NASA Technical Reports Server (NTRS)

    Wolpert, David H.; Lawson, John W.; Clancy, Daniel (Technical Monitor)

    2001-01-01

    The "Collective Intelligence" (COIN) framework concerns the design of collectives of agents so that as those agents strive to maximize their individual utility functions, their interaction causes a provided "world" utility function concerning the entire collective to be also maximized. Here we show how to extend that framework to scenarios having Markovian dynamics when no re-evolution of the system from counter-factual initial conditions (an often expensive calculation) is permitted. Our approach transforms the (time-extended) argument of each agent's utility function before evaluating that function. This transformation has benefits in scenarios not involving Markovian dynamics, in particular scenarios where not all of the arguments of an agent's utility function are observable. We investigate this transformation in simulations involving both linear and quadratic (nonlinear) dynamics. In addition, we find that a certain subset of these transformations, which result in utilities that have low "opacity (analogous to having high signal to noise) but are not "factored" (analogous to not being incentive compatible), reliably improve performance over that arising with factored utilities. We also present a Taylor Series method for the fully general nonlinear case.

  8. Designing Agent Collectives For Systems With Markovian Dynamics

    NASA Technical Reports Server (NTRS)

    Wolpert, David H.; Lawson, John W.

    2004-01-01

    The Collective Intelligence (COIN) framework concerns the design of collectives of agents so that as those agents strive to maximize their individual utility functions, their interaction causes a provided world utility function concerning the entire collective to be also maximized. Here we show how to extend that framework to scenarios having Markovian dynamics when no re-evolution of the system from counter-factual initial conditions (an often expensive calculation) is permitted. Our approach transforms the (time-extended) argument of each agent's utility function before evaluating that function. This transformation has benefits in scenarios not involving Markovian dynamics of an agent's utility function are observable. We investigate this transformation in simulations involving both hear and quadratic (nonlinear) dynamics. In addition, we find that a certain subset of these transformations, which result in utilities that have low opacity (analogous to having high signal to noise) but are not factored (analogous to not being incentive compatible), reliably improve performance over that arising with factored utilities. We also present a Taylor Series method for the fully general nonlinear case.

  9. Antitubercular Agent Delamanid and Metabolites as Substrates and Inhibitors of ABC and Solute Carrier Transporters

    PubMed Central

    Shimokawa, Yoshihiko; Shibata, Masakazu; Hashizume, Kenta; Hamasako, Yusuke; Ohzone, Yoshihiro; Kashiyama, Eiji; Umehara, Ken

    2016-01-01

    Delamanid (Deltyba, OPC-67683) is the first approved drug in a novel class of nitro-dihydro-imidazooxazoles developed for the treatment of multidrug-resistant tuberculosis. Patients with tuberculosis require treatment with multiple drugs, several of which have known drug-drug interactions. Transporters regulate drug absorption, distribution, and excretion; therefore, the inhibition of transport by one agent may alter the pharmacokinetics of another, leading to unexpected adverse events. Therefore, it is important to understand how delamanid affects transport activity. In the present study, the potencies of delamanid and its main metabolites as the substrates and inhibitors of various transporters were evaluated in vitro. Delamanid was not transported by the efflux ATP-binding cassette (ABC) transporters P-glycoprotein (P-gp; MDR1/ABCB1) and breast cancer resistance protein (BCRP/ABCG2), solute carrier (SLC) transporters, organic anion-transporting polypeptides, or organic cation transporter 1. Similarly, metabolite 1 (M1) was not a substrate for any of these transporters except P-gp. Delamanid showed no inhibitory effect on ABC transporters MDR1, BCRP, and bile salt export pump (BSEP; ABCB11), SLC transporters, or organic anion transporters. M1 and M2 inhibited P-gp- and BCRP-mediated transport but did so only at the 50% inhibitory concentrations (M1, 4.65 and 5.71 μmol/liter, respectively; M2, 7.80 and 6.02 μmol/liter, respectively), well above the corresponding maximum concentration in plasma values observed following the administration of multiple doses in clinical trials. M3 and M4 did not affect the activities of any of the transporters tested. These in vitro data suggest that delamanid is unlikely to have clinically relevant interactions with drugs for which absorption and disposition are mediated by this group of transporters. PMID:27021329

  10. A Multi-Agent Approach to the Simulation of Robotized Manufacturing Systems

    NASA Astrophysics Data System (ADS)

    Foit, K.; Gwiazda, A.; Banaś, W.

    2016-08-01

    The recent years of eventful industry development, brought many competing products, addressed to the same market segment. The shortening of a development cycle became a necessity if the company would like to be competitive. Because of switching to the Intelligent Manufacturing model the industry search for new scheduling algorithms, while the traditional ones do not meet the current requirements. The agent-based approach has been considered by many researchers as an important way of evolution of modern manufacturing systems. Due to the properties of the multi-agent systems, this methodology is very helpful during creation of the model of production system, allowing depicting both processing and informational part. The complexity of such approach makes the analysis impossible without the computer assistance. Computer simulation still uses a mathematical model to recreate a real situation, but nowadays the 2D or 3D virtual environments or even virtual reality have been used for realistic illustration of the considered systems. This paper will focus on robotized manufacturing system and will present the one of possible approaches to the simulation of such systems. The selection of multi-agent approach is motivated by the flexibility of this solution that offers the modularity, robustness and autonomy.

  11. An Embedded Multi-Agent Systems Based Industrial Wireless Sensor Network.

    PubMed

    Taboun, Mohammed S; Brennan, Robert W

    2017-09-14

    With the emergence of cyber-physical systems, there has been a growing interest in network-connected devices. One of the key requirements of a cyber-physical device is the ability to sense its environment. Wireless sensor networks are a widely-accepted solution for this requirement. In this study, an embedded multi-agent systems-managed wireless sensor network is presented. A novel architecture is proposed, along with a novel wireless sensor network architecture. Active and passive wireless sensor node types are defined, along with their communication protocols, and two application-specific examples are presented. A series of three experiments is conducted to evaluate the performance of the agent-embedded wireless sensor network.

  12. An Embedded Multi-Agent Systems Based Industrial Wireless Sensor Network

    PubMed Central

    Brennan, Robert W.

    2017-01-01

    With the emergence of cyber-physical systems, there has been a growing interest in network-connected devices. One of the key requirements of a cyber-physical device is the ability to sense its environment. Wireless sensor networks are a widely-accepted solution for this requirement. In this study, an embedded multi-agent systems-managed wireless sensor network is presented. A novel architecture is proposed, along with a novel wireless sensor network architecture. Active and passive wireless sensor node types are defined, along with their communication protocols, and two application-specific examples are presented. A series of three experiments is conducted to evaluate the performance of the agent-embedded wireless sensor network. PMID:28906452

  13. A multi-agent system architecture for geographic information gathering.

    PubMed

    Gao, Gang-Yi; Wang, Shen-Kang

    2004-11-01

    World Wide Web (WWW) is a vast repository of information, including a great deal of geographic information. But the location and retrieval of geographic information will require a significant amount of time and effort. In addition, different users usually have different views and interests in the same information. To resolve such problems, this paper first proposed a model of geographic information gathering based on multi-Agent (MA) architecture. Then based on this model, we construct a prototype system with GML (Geography Markup Language). This system consists of three tiers-Client, Web Server and Data Resource. Finally, we expatiate on the process of Web Server.

  14. A Descriptive Analysis of the Del Mod System's Field Agent Component, Final Report, Volume III.

    ERIC Educational Resources Information Center

    Golts, Uldis R.

    This monograph describes the field agent of the Delaware Del Mod System. The following sections are included in the report: (1) The Duties and Activities of the Del Mod System Field Agents; (2) The Field Agents' Mode of Operation; (3) The Conduct of Projects; (4) The Hiring and Training of Del Mod Field Agents; (5) The Administration of Del Mod…

  15. Model-Drive Architecture for Agent-Based Systems

    NASA Technical Reports Server (NTRS)

    Gradanin, Denis; Singh, H. Lally; Bohner, Shawn A.; Hinchey, Michael G.

    2004-01-01

    The Model Driven Architecture (MDA) approach uses a platform-independent model to define system functionality, or requirements, using some specification language. The requirements are then translated to a platform-specific model for implementation. An agent architecture based on the human cognitive model of planning, the Cognitive Agent Architecture (Cougaar) is selected for the implementation platform. The resulting Cougaar MDA prescribes certain kinds of models to be used, how those models may be prepared and the relationships of the different kinds of models. Using the existing Cougaar architecture, the level of application composition is elevated from individual components to domain level model specifications in order to generate software artifacts. The software artifacts generation is based on a metamodel. Each component maps to a UML structured component which is then converted into multiple artifacts: Cougaar/Java code, documentation, and test cases.

  16. Hereditary cancer syndromes as model systems for chemopreventive agent development.

    PubMed

    Walcott, Farzana L; Patel, Jigar; Lubet, Ronald; Rodriguez, Luz; Calzone, Kathleen A

    2016-02-01

    Research in chemoprevention has undergone a shift in emphasis for pragmatic reasons from large, phase III randomized studies to earlier phase studies focused on safety, mechanisms, and utilization of surrogate endpoints such as biomarkers instead of cancer incidence. This transition permits trials to be conducted in smaller populations and at substantially reduced costs while still yielding valuable information. This article will summarize some of the current chemoprevention challenges and the justification for the use of animal models to facilitate identification and testing of chemopreventive agents as illustrated though four inherited cancer syndromes. Preclinical models of inherited cancer syndromes serve as prototypical systems in which chemopreventive agents can be developed for ultimate application to both the sporadic and inherited cancer settings.

  17. The solution for RPR over MSTP system

    NASA Astrophysics Data System (ADS)

    Tao, Zhiyong; Yang, JiuMin; Liu, Guohui

    2004-04-01

    The rapid development of the data service has brought great challenge to the traditional telecommunication network. The integrated broadband MAN with large information capability, high subscriber density and multiple sorts of services, is becoming the hot point and competitive focus of the telecommunication field. Resilient packet ring (RPR) is a new metropolitan area network (MAN) technology supporting data transfer among stations interconnected in a dual-ring configuration. Key features of RPR include: Low-delay guaranteed rate, bounded delay committed rate, and best effort service classes; 50 millisecond service restoration following a single station or link failure; Ring capacity reuse downstream of unicast destination (spatial reuse); Weighted fair access to available ring capacity; Point-of-congestion aware flow control (allowing per destination queuing in client). But RPR is belong to layer 2 technology. SDH have already become the dominant optical transport network technology, and it is considered to be one of foundation for the physical layer of the broadband IP network. But SDH is taken as a voice-fit technology. This paper fully make use of RPR & SDH advantages to provide The integrated broadband MAN solution, this is the RPR over MSTP System. The architecture of RPR over MSTP and key technologies of realization of RPR over MSTP node is provided. The main technical specification of RPR over MSTP node is also provided.

  18. Optimal parallel solution of sparse triangular systems

    NASA Technical Reports Server (NTRS)

    Alvarado, Fernando L.; Schreiber, Robert

    1990-01-01

    A method for the parallel solution of triangular sets of equations is described that is appropriate when there are many right-handed sides. By preprocessing, the method can reduce the number of parallel steps required to solve Lx = b compared to parallel forward or backsolve. Applications are to iterative solvers with triangular preconditioners, to structural analysis, or to power systems applications, where there may be many right-handed sides (not all available a priori). The inverse of L is represented as a product of sparse triangular factors. The problem is to find a factored representation of this inverse of L with the smallest number of factors (or partitions), subject to the requirement that no new nonzero elements be created in the formation of these inverse factors. A method from an earlier reference is shown to solve this problem. This method is improved upon by constructing a permutation of the rows and columns of L that preserves triangularity and allow for the best possible such partition. A number of practical examples and algorithmic details are presented. The parallelism attainable is illustrated by means of elimination trees and clique trees.

  19. Building interoperable health information systems using agent and workflow technologies.

    PubMed

    Koufi, Vassiliki; Malamateniou, Flora; Vassilacopoulos, George

    2009-01-01

    Healthcare is an increasingly collaborative enterprise involving many individuals and organizations that coordinate their efforts toward promoting quality and efficient delivery of healthcare through the use of interoperable healthcare information systems. This paper presents a mediator-based approach for achieving data and service interoperability among disparate and geographically dispersed healthcare information systems. The proposed system architecture enables decoupling of the client applications and the server-side implementations while it ensures security in all transactions. It is a distributed system architecture based on the agent-oriented paradigm for communication and life cycle management while interactions are described according to the workflow metaphor. Thus robustness, high flexibility and fault tolerance are provided in an environment as dynamic and heterogeneous as healthcare.

  20. System integration and development for biological warfare agent surveillance

    NASA Astrophysics Data System (ADS)

    Mark, Jacob A.; Green, Lance D.; Deshpande, Alina; White, P. Scott

    2007-04-01

    A wide variety of technical needs exist for surveillance, monitoring, identifying, or detecting pathogens with potential use as biological terrorism or warfare agents. Because the needs vary greatly among diverse applications, tailored systems are needed that meet performance, information, and cost requirements. A systems perspective allows developers to identify chokepoints for each application, and focus R&D investments on the limiting factors. Surveillance and detection systems are comprised of three primary components: information (markers), chemistries (assays), and instrumentation for "readout". Careful consideration of these components within the context of each application will allow for increases in efficiency and performance not generally realized when researchers focus on a single component in isolation. In fact, many application requirements can be met with simple novel combinations of existing technologies, without the need for huge investments in basic research. Here we discuss some of the key parameters for surveillance, detection, and identification of biothreat agents, and provide examples of focused development that addresses key bottlenecks, and greatly improve system performance.

  1. Simplified solution of diffraction from a Lyot system

    NASA Astrophysics Data System (ADS)

    Wang, Yaujen; Vaughan, Arthur H.

    1988-01-01

    This paper presents a derivation of a simplified analytical solution of diffraction from a Lyot (1939) system designed for observation of the solar corona outside of eclipses. Applying the theorem of Papoulis (1986) to simplify the calculations, a simplified solution is derived which is found to be in reasonable agreement with the exact solution. The simplified solution suffices for the preliminary evaluation of the amount of diffraction reduction needed to meet certain system requirements and also serves as a guideline for further apodization.

  2. Central Nervous System Agents for Ischemic Stroke: Neuroprotection Mechanisms

    PubMed Central

    Pandya, Rachna S.; Mao, Lijuan; Zhou, Hua; Zhou, Shuanhu; Zeng, Jiang; Popp, A. John; Wang, Xin

    2011-01-01

    Stroke is the third leading cause of mortality and disability in the United States. Ischemic stroke constitutes 85% of all stroke cases. However, no effective treatment has been found to prevent damage to the brain in such cases except tissue plasminogen activator with narrow therapeutic window, and there is an unmet need to develop therapeutics for neuroprotection from ischemic stroke. Studies have shown that mechanisms including apoptosis, necrosis, inflammation, immune modulation, and oxidative stress and mediators such as excitatory amino acids, nitric oxide, inflammatory mediators, neurotransmitters, reactive oxygen species, and withdrawal of trophic factors may lead to the development of the ischemic cascade. Hence, it is essential to develop neuroprotective agents targeting either the mechanisms or the mediators leading to development of ischemic stroke. This review focuses on central nervous system agents targeting these biochemical pathways and mediators of ischemic stroke, mainly those that counteract apoptosis, inflammation, and oxidation, and well as glutamate inhibitors which have been shown to provide neuroprotection in experimental animals. All these agents have been shown to improve neurological outcome after ischemic insult in experimental animals in vivo, organotypic brain slice/acute slice ex vivo, and cell cultures in vitro and may therefore aid in preventing long-term morbidity and mortality associated with ischemic stroke. PMID:21521165

  3. Eight challenges in modelling disease ecology in multi-host, multi-agent systems.

    PubMed

    Buhnerkempe, Michael G; Roberts, Mick G; Dobson, Andrew P; Heesterbeek, Hans; Hudson, Peter J; Lloyd-Smith, James O

    2015-03-01

    Many disease systems exhibit complexities not captured by current theoretical and empirical work. In particular, systems with multiple host species and multiple infectious agents (i.e., multi-host, multi-agent systems) require novel methods to extend the wealth of knowledge acquired studying primarily single-host, single-agent systems. We outline eight challenges in multi-host, multi-agent systems that could substantively increase our knowledge of the drivers and broader ecosystem effects of infectious disease dynamics.

  4. Quantum chemical and solution phase evaluation of metallocenes as reducing agents for the prospective atomic layer deposition of copper.

    PubMed

    Dey, Gangotri; Wrench, Jacqueline S; Hagen, Dirk J; Keeney, Lynette; Elliott, Simon D

    2015-06-14

    We propose and evaluate the use of metallocene compounds as reducing agents for the chemical vapour deposition (and specifically atomic layer deposition, ALD) of the transition metal Cu from metalorganic precursors. Ten different transition metal cyclopentadienyl compounds are screened for their utility in the reduction of Cu from five different Cu precursors by evaluating model reaction energies with density functional theory (DFT) and solution phase chemistry.

  5. Application of poly (ethyleneimine) solution as a binding agent in DGT technique for measurement of heavy metals in water.

    PubMed

    Sui, Dian-Peng; Fan, Hong-Tao; Li, Jing; Li, You; Li, Qiong; Sun, Ting

    2013-09-30

    A 0.050 mol L(-1) solution of poly (ethyleneimine) (PEI), had been used as a novel binding agent of diffusive gradients in thin-films (DGT) technique (PEI-DGT) for measuring the concentrations of labile Cu(2+), Cd(2+) and Pb(2+) in waters. The binding capacities of the PEI-DGT for Cu(2+), Cd(2+) and Pb(2+) were 11.8, 10.2 and 10.6 μmol L(-1), respectively. The performance of PEI-DGT was independence of pH in the range of 4-8 and ionic strength in the range from 1×10(-4) to 0.1 mol L(-1) (as NaNO3). PEI-DGT could measure 104.7±5.2% of the total concentration of Cd(2+) (0.500 mg L(-1)), 95.2±4.3% of the total Cu(2+) (0.500 mg L(-1)) and 99.2±3.4% of the total Pb(2+) (0.500 mg L(-1)) in synthetic solution. Effects of the ligands on the measurement of labile metals were also investigated in synthetic solutions containing the various concentrations of EDTA and humic acid. In EDTA solution, the concentrations of labile metals measured by PEI-DGT showed good agreement with the theoretical concentrations of free metal ions. In humic acid solution, the concentrations of labile metals measured by PEI-DGT decreased with the increase of the concentrations of humic acid. Several DGT devices with various binding agents, including PEI, sodium polyacrylate and poly(4-styrenesulfonate) solution, were used for the measurement of labile fractions of Cu(2+), Cd(2+) and Pb(2+) in the spiked waters and in mine wastewaters. The results showed that the concentrations of labile metal measured by DGT devices with different binding agents could be significantly different, indicating that the labile fractions of metals were dependent on the binding strength of the binding agents with metals. By choosing binding agents, the useful information on the speciation and bioavailability of the analytes can be provided. Copyright © 2013 Elsevier B.V. All rights reserved.

  6. Interaction of nerve agent antidotes with cholinergic systems.

    PubMed

    Soukup, O; Tobin, G; Kumar, U K; Binder, J; Proska, J; Jun, D; Fusek, J; Kuca, K

    2010-01-01

    The poisoning with organophosphorus compounds represents a life threatening danger especially in the time of terroristic menace. No universal antidote has been developed yet and other therapeutic approaches not related to reactivation of acetylcholinesterase are being investigated. This review describes the main features of the cholinergic system, cholinergic receptors, cholinesterases and their inhibitors. It also focuses on the organophosphorus nerve agents, their properties, effects and a large part describes various possibilities in treatments, mainly traditional oxime therapies based on reactivation of AChE. Furthermore, non-cholinesterase coupled antidotal effects of the oximes are thoroughly discussed. These antidotal effects principally include oxime interactions with muscarinic and nicotinic receptors.

  7. Interaction of cyanocobalamin with sulfur-containing reducing agents in aqueous solutions

    NASA Astrophysics Data System (ADS)

    Salnikov, D. S.; Dereven'kov, I. A.; Artyushina, E. N.; Makarov, S. V.

    2013-01-01

    The kinetics and mechanism of cyanocobalamin reduction by sodium hydroxymethanesulfinate and dithionite in alkaline media are studied. It is established that the character of the rate-determining step depends on the concentration of the reducing agents: when they are in excess, it is a step of elimination of cyanocobalamin, at lower concentrations of reducing agents a rate-determining is a step of their addition to cobalamin.

  8. Laser-induced chemical liquid phase deposition of copper from aqueous solutions without reducing agents

    SciTech Connect

    Kochemirovsky, V A; Tumkin, I I; Logunov, L S; Safonov, S V; Menchikov, Leonid G

    2012-08-31

    Laser-induced chemical liquid phase deposition of copper without a traditional reducing agent has been used for the first time to obtain conductive patterns on a dielectric surface having a reducing ability. It is shown that phenol-formaldehyde binder of the dielectric (glass fibre) can successfully play the role of a reducing agent in this process. The resulting copper sediments have low electrical resistance and good topology. (interaction of laser radiation with matter. laser plasmas)

  9. Laboratory Evaluation of the Clean Earth Technologies Decontamination Solutions for Chemical and Biological Agents

    DTIC Science & Technology

    2008-01-01

    collected from the first reactor and placed in a 5-mm NMR tube. GC-AED Analysis: GC analysis was performed on a Hewlett Packard (HP) 6890 gas chromatograph...helium as the carrier gas was employed. The carbon channel was used in the analysis of all three agents. Phosphorus was used only in the analysis of GD...and reactor samples was performed using a Varian 400-MHz narrow bore spectrometer equipped with a 5-mm broad band liquids probe. Agent feedstock

  10. System solution to improve energy efficiency of HVAC systems

    NASA Astrophysics Data System (ADS)

    Chretien, L.; Becerra, R.; Salts, N. P.; Groll, E. A.

    2017-08-01

    According to recent surveys, heating and air conditioning systems account for over 45% of the total energy usage in US households. Three main types of HVAC systems are available to homeowners: (1) fixed-speed systems, where the compressor cycles on and off to match the cooling load; (2) multi-speed (typically, two-speed) systems, where the compressor can operate at multiple cooling capacities, leading to reduced cycling; and (3) variable-speed systems, where the compressor speed is adjusted to match the cooling load of the household, thereby providing higher efficiency and comfort levels through better temperature and humidity control. While energy consumption could reduce significantly by adopting variable-speed compressor systems, the market penetration has been limited to less than 10% of the total HVAC units and a vast majority of systems installed in new construction remains single speed. A few reasons may explain this phenomenon such as the complexity of the electronic circuitry required to vary compressor speed as well as the associated system cost. This paper outlines a system solution to boost the Seasonal Energy Efficiency Rating (SEER) of a traditional single-speed unit through using a low power electronic converter that allows the compressor to operate at multiple low capacity settings and is disabled at high compressor speeds.

  11. Multi-agent cooperative systems applied to precision applications

    SciTech Connect

    McKay, M.D.; Anderson, M.O.; Gunderson, R.W.; Flann, N.; Abbott, B.

    1998-03-01

    Regulatory agencies are imposing limits and constraints to protect the operator and/or the environment. While generally necessary, these controls also tend to increase cost and decrease efficiency and productivity. Intelligent computer systems can be made to perform these hazardous tasks with greater efficiency and precision without danger to the operators. The Idaho national Engineering and Environmental Laboratory and the Center for Self-Organizing and Intelligent Systems at Utah State University have developed a series of autonomous all-terrain multi-agent systems capable of performing automated tasks within hazardous environments. This paper discusses the development and application of cooperative small-scale and large-scale robots for use in various activities associated with radiologically contaminated areas, prescription farming, and unexploded ordinances.

  12. The effect of chelating agent on the separation of Fe(III) and Ti(IV) from binary mixture solution by cation-exchange membrane.

    PubMed

    Kir, Esengül; Cengeloğlu, Yunus; Ersöz, Mustafa

    2005-12-15

    The competitive transport of Fe(III) and Ti(IV) ions and the effect of chelating agents on separation from binary mixture solutions through charged polysulfone cation-exchange membrane (SA3S) has been studied under Donnan dialysis conditions. The amount of chelating agent was taken as an equimolar of Fe(III) ion in the feed phase. In this process, the membrane separated two electrolyte solutions: the feed solution, initially containing metal salts (Fe, Ti), or metal salts solution, containing a chelating agent, and the other side (receiver solution) being HCl solution. An external potential field is not applied. It was observed that the chelating agents affect the metal transport; the transport of Fe(III) is decreased and the transport of Ti(IV) is increased.

  13. Multiple-Agent Air/Ground Autonomous Exploration Systems

    NASA Technical Reports Server (NTRS)

    Fink, Wolfgang; Chao, Tien-Hsin; Tarbell, Mark; Dohm, James M.

    2007-01-01

    Autonomous systems of multiple-agent air/ground robotic units for exploration of the surfaces of remote planets are undergoing development. Modified versions of these systems could be used on Earth to perform tasks in environments dangerous or inaccessible to humans: examples of tasks could include scientific exploration of remote regions of Antarctica, removal of land mines, cleanup of hazardous chemicals, and military reconnaissance. A basic system according to this concept (see figure) would include a unit, suspended by a balloon or a blimp, that would be in radio communication with multiple robotic ground vehicles (rovers) equipped with video cameras and possibly other sensors for scientific exploration. The airborne unit would be free-floating, controlled by thrusters, or tethered either to one of the rovers or to a stationary object in or on the ground. Each rover would contain a semi-autonomous control system for maneuvering and would function under the supervision of a control system in the airborne unit. The rover maneuvering control system would utilize imagery from the onboard camera to navigate around obstacles. Avoidance of obstacles would also be aided by readout from an onboard (e.g., ultrasonic) sensor. Together, the rover and airborne control systems would constitute an overarching closed-loop control system to coordinate scientific exploration by the rovers.

  14. Multi-Agent Design and Implementation for an Online Peer Help System

    ERIC Educational Resources Information Center

    Meng, Anbo

    2014-01-01

    With the rapid advance of e-learning, the online peer help is playing increasingly important role. This paper explores the application of MAS to an online peer help system (MAPS). In the design phase, the architecture of MAPS is proposed, which consists of a set of agents including the personal agent, the course agent, the diagnosis agent, the DF…

  15. Multi-Agent Design and Implementation for an Online Peer Help System

    ERIC Educational Resources Information Center

    Meng, Anbo

    2014-01-01

    With the rapid advance of e-learning, the online peer help is playing increasingly important role. This paper explores the application of MAS to an online peer help system (MAPS). In the design phase, the architecture of MAPS is proposed, which consists of a set of agents including the personal agent, the course agent, the diagnosis agent, the DF…

  16. Deployment of secure mobile agents for medical information systems.

    PubMed

    Chen, Tzer-Long; Chung, Yu-Fang; Lin, Frank Y S

    2012-08-01

    Changes in global population and demography, and advances in medicine have led to elderly population growth, creating aging societies from which elderly medical care has evolved. In addition, with the elderly susceptible to chronic diseases, this together with the changing lifestyles of young adults have not only pushed up patient numbers of chronic diseases, but also effected into younger patients. These problems have become the major focus for the health care industry. In response to patient demand and the huge shortage of medical resources, we propose remote healthcare medical information systems that combine patient physiological data acquisition equipment with real-time health care analyses. Since remote health care systems are structured around the Internet, in addition to considering the numerous public systems spread across insecure heterogeneous networks, compatibility among heterogeneous networks will also be another concern. To address the aforementioned issues, mobile agents are adopted. With a mobile agent's characteristics of easy adaptability to heterogeneity and autonomy, the problem of heterogeneous network environments can be tackled. To construct a hierarchical safe access control mechanism for monitoring and control of patient data in order to provide the most appropriate medical treatment, we also propose to use the Chinese Remainder Theorem and discrete logarithm to classify different levels of monitoring staff and hence, to grant permission and access according to their authorized levels. We expect the methods proposed can improve medical care quality and reduce medical resource wastage, while ensuring patient privacy. Finally, security analysis of the system is conducted by simulating a variety of typical attacks, from which it can be concluded that the constructed remote healthcare information system be secure.

  17. Positive solutions of quasilinear parabolic systems with nonlinear boundary conditions

    NASA Astrophysics Data System (ADS)

    Pao, C. V.; Ruan, W. H.

    2007-09-01

    The aim of this paper is to investigate the existence, uniqueness, and asymptotic behavior of solutions for a coupled system of quasilinear parabolic equations under nonlinear boundary conditions, including a system of quasilinear parabolic and ordinary differential equations. Also investigated is the existence of positive maximal and minimal solutions of the corresponding quasilinear elliptic system as well as the uniqueness of a positive steady-state solution. The elliptic operators in both systems are allowed to be degenerate in the sense that the density-dependent diffusion coefficients Di(ui) may have the property Di(0)=0 for some or all i. Our approach to the problem is by the method of upper and lower solutions and its associated monotone iterations. It is shown that the time-dependent solution converges to the maximal solution for one class of initial functions and it converges to the minimal solution for another class of initial functions; and if the maximal and minimal solutions coincide then the steady-state solution is unique and the time-dependent solution converges to the unique solution. Applications of these results are given to three model problems, including a porous medium type of problem, a heat-transfer problem, and a two-component competition model in ecology. These applications illustrate some very interesting distinctive behavior of the time-dependent solutions between density-independent and density-dependent diffusions.

  18. Distributed Cooperation Solution Method of Complex System Based on MAS

    NASA Astrophysics Data System (ADS)

    Weijin, Jiang; Yuhui, Xu

    To adapt the model in reconfiguring fault diagnosing to dynamic environment and the needs of solving the tasks of complex system fully, the paper introduced multi-Agent and related technology to the complicated fault diagnosis, an integrated intelligent control system is studied in this paper. Based on the thought of the structure of diagnostic decision and hierarchy in modeling, based on multi-layer decomposition strategy of diagnosis task, a multi-agent synchronous diagnosis federation integrated different knowledge expression modes and inference mechanisms are presented, the functions of management agent, diagnosis agent and decision agent are analyzed, the organization and evolution of agents in the system are proposed, and the corresponding conflict resolution algorithm in given, Layered structure of abstract agent with public attributes is build. System architecture is realized based on MAS distributed layered blackboard. The real world application shows that the proposed control structure successfully solves the fault diagnose problem of the complex plant, and the special advantage in the distributed domain.

  19. Exposure of ventilation system cleaning workers to harmful microbiological agents.

    PubMed

    Gołofit-Szymczak, Małgorzata; Ławniczek-Wałczyk, Anna; Górny, Rafał L

    2013-01-01

    Regular inspection of the cleanliness of the ventilation systems, as well as their periodic cleaning and disinfection, if necessary, are the main factors of the proper maintenance of each system. Performing maintenance operations on the ventilation system, workers are exposed to risk associated with the exposure to harmful biological agents. The aim of this study was to assess the employees' exposure to bioaerosols during maintenance work on ventilation systems. Bioaerosol measurements were carried out using a button sampler. The microbial particles were collected on gelatin filters. Settled-dust samples from the inner surface of the air ducts and filter-mat samples were selected for the microbiological analysis. In the collected air, dust and filter samples the concentration of bacteria and fungi were determined. Bacteria and fungi concentrations ranged between 3.6 x 10(2)-2.2 x 10(4) CFU/m3 and 4.7 x 10(2)-4.5 x 10(3) CFU/m3 at workplaces where the operations connected with mechanical ventilation cleaning were performed and 2.2 x 10(4)-1.2 x 10(5) CFU/m2 and 9.8 x 10(1)-2.5 x 10(2) CFU/m3 at workplaces where filter exchange was performed, respectively. The qualitative analysis of microorganisms isolated from the air in all studied workplaces revealed that the most prevalent bacteria belonged to Bacillus genus. The average concentrations of bacteria and fungi in filter-mat samples were 3.3 x 10(3) CFU/cm2 and 1.4 x 10(4) CFU/cm2, respectively. In settled-dust samples, average concentrations were 591 CFU/100 cm2 and 52 CFU/100 cm2, for bacteria and fungi respectively. Workers cleaning ventilation systems are exposed to harmful biological agents classified into risk groups, 1 and 2, according to their level of the risk of infection. The research conducted in the workplace can be the basis of risk assessment related to exposure to harmful biological agents during maintenance work in ventilation.

  20. Assessment of disinfectants in explosive destruction system for biological agent destruction : LDRD final report FY04.

    SciTech Connect

    Simmons, Blake Alexander; Didlake, John E. Jr.; Bradshaw, Robert W.; Crooker, Paul J.; Buffleben, George M.

    2005-01-01

    Treatment systems that can neutralize biological agents are needed to mitigate risks from novel and legacy biohazards. Tests with Bacillus thuringiensis and Bacillus steurothemophilus spores were performed in a 190-liter, 1-112 lb TNT equivalent rated Explosive Destruction System (EDS) system to evaluate its capability to treat and destroy biological agents. Five tests were conducted using three different agents to kill the spores. The EDS was operated in steam autoclave, gas fumigation and liquid decontamination modes. The first three tests used EDS as an autoclave, which uses pressurized steam to kill the spores. Autoclaving was performed at 130-140 deg C for up to 2-hours. Tests with chlorine dioxide at 750 ppm concentration for 1 hour and 10% (vol) aqueous chlorine bleach solution for 1 hour were also performed. All tests resulted in complete neutralization of the bacterial spores based on no bacterial growth in post-treatment incubations. Explosively opening a glass container to expose the bacterial spores for treatment with steam was demonstrated and could easily be done for chlorine dioxide gas or liquid bleach.

  1. Mobile agent application and integration in electronic anamnesis system.

    PubMed

    Liu, Chia-Hui; Chung, Yu-Fang; Chen, Tzer-Shyong; Wang, Sheng-De

    2012-06-01

    Electronic anamnesis is to transform ordinary paper trails to digitally formatted health records, which include the patient's general information, health status, and follow-ups on chronic diseases. Its main purpose is to let the records could be stored for a longer period of time and could be shared easily across departments and hospitals. Which means hospital management could use less resource on maintaining ever-growing database and reduce redundancy, so less money would be spent for managing the health records. In the foreseeable future, building up a comprehensive and integrated medical information system is a must, because it is critical to hospital resource integration and quality improvement. If mobile agent technology is adopted in the electronic anamnesis system, it would help the hospitals to make the medical practices more efficiently and conveniently. Nonetheless, most of the hospitals today are still using paper-based health records to manage the medical information. The reason why the institutions continue using traditional practices to manage the records is because there is no well-trusted and reliable electronic anamnesis system existing and accepted by both institutions and patients. The threat of privacy invasion is one of the biggest concerns when the topic of electronic anamnesis is brought up, because the security threats drag us back from using such a system. So, the medical service quality is difficult to be improved substantially. In this case, we have come up a theory to remove such security threats and make electronic anamnesis more appealing for use. Our theory is to integrate the mobile agent technology with the backbone of electronic anamnesis to construct a hierarchical access control system to retrieve the corresponding information based upon the permission classes. The system would create a classification for permission among the users inside the medical institution. Under this framework, permission control center would distribute an

  2. MonALISA: An agent based, dynamic service system to monitor, control and optimize distributed systems

    NASA Astrophysics Data System (ADS)

    Legrand, I.; Newman, H.; Voicu, R.; Cirstoiu, C.; Grigoras, C.; Dobre, C.; Muraru, A.; Costan, A.; Dediu, M.; Stratan, C.

    2009-12-01

    distributed computing clusters and grids, the network infrastructure, the storage systems, and the applications used on such facilities. The monitoring information gathered is used for developing the required higher level services, the components that provide decision support and some degree of automated decisions and for maintaining and optimizing workflow in large scale distributed systems. Solution method: The MonALISA framework is designed as an ensemble of autonomous self-describing agent-based subsystems which are registered as dynamic services. These services are able to collaborate and cooperate in performing a wide range of distributed information-gathering and processing tasks. Running time: MonALISA services are designed to run continuously to collect monitoring data and to trigger alarms or to take automatic actions in case it is necessary. References:http://monalisa.caltech.edu.

  3. A Comparative Study of Probability Collectives Based Multi-agent Systems and Genetic Algorithms

    NASA Technical Reports Server (NTRS)

    Huang, Chien-Feng; Wolpert, David H.; Bieniawski, Stefan; Strauss, Charles E. M.

    2005-01-01

    We compare Genetic Algorithms (GA's) with Probability Collectives (PC), a new framework for distributed optimization and control. In contrast to GA's, PC-based methods do not update populations of solutions. Instead they update an explicitly parameterized probability distribution p over the space of solutions. That updating of p arises as the optimization of a functional of p. The functional is chosen so that any p that optimizes it should be p peaked about good solutions. The PC approach works in both continuous and discrete problems. It does not suffer from the resolution limitation of the finite bit length encoding of parameters into GA alleles. It also has deep connections with both game theory and statistical physics. We review the PC approach using its motivation as the information theoretic formulation of bounded rationality for multi-agent systems. It is then compared with GA's on a diverse set of problems. To handle high dimensional surfaces, in the PC method investigated here p is restricted to a product distribution. Each distribution in that product is controlled by a separate agent. The test functions were selected for their difficulty using either traditional gradient descent or genetic algorithms. On those functions the PC-based approach significantly outperforms traditional GA's in both rate of descent, trapping in false minima, and long term optimization.

  4. An Approach to Quantify Workload in a System of Agents

    NASA Technical Reports Server (NTRS)

    Stocker, Richard; Rungta, Neha; Mercer, Eric; Raimondi, Franco; Holbrook, Jon; Cardoza, Colleen; Goodrich, Michael

    2015-01-01

    The role of humans in aviation and other domains continues to shift from manual control to automation monitoring. Studies have found that humans are often poorly suited for monitoring roles, and workload can easily spike in off-nominal situations. Current workload measurement tools, like NASA TLX, use human operators to assess their own workload after using a prototype system. Such measures are used late in the design process and can result in ex- pensive alterations when problems are discovered. Our goal in this work is to provide a quantitative workload measure for use early in the design process. We leverage research in human cognition to de ne metrics that can measure workload on belief-desire-intentions based multi-agent systems. These measures can alert designers to potential workload issues early in design. We demonstrate the utility of our approach by characterizing quantitative differences in the workload for a single pilot operations model compared to a traditional two pilot model.

  5. Solution of linear systems by a singular perturbation technique

    NASA Technical Reports Server (NTRS)

    Ardema, M. D.

    1976-01-01

    An approximate solution is obtained for a singularly perturbed system of initial valued, time invariant, linear differential equations with multiple boundary layers. Conditions are stated under which the approximate solution converges uniformly to the exact solution as the perturbation parameter tends to zero. The solution is obtained by the method of matched asymptotic expansions. Use of the results for obtaining approximate solutions of general linear systems is discussed. An example is considered to illustrate the method and it is shown that the formulas derived give a readily computed uniform approximation.

  6. Learning and stabilization of altruistic behaviors in multi-agent systems by reciprocity.

    PubMed

    Zamora, J; Millán, J R; Murciano, A

    1998-03-01

    Optimization of performance in collective systems often requires altruism. The emergence and stabilization of altruistic behaviors are difficult to achieve because the agents incur a cost when behaving altruistically. In this paper, we propose a biologically inspired strategy to learn stable altruistic behaviors in artificial multi-agent systems, namely reciprocal altruism. This strategy in conjunction with learning capabilities make altruistic agents cooperate only between themselves, thus preventing their exploitation by selfish agents, if future benefits are greater than the current cost of altruistic acts. Our multi-agent system is made up of agents with a behavior-based architecture. Agents learn the most suitable cooperative strategy for different environments by means of a reinforcement learning algorithm. Each agent receives a reinforcement signal that only measures its individual performance. Simulation results show how the multi-agent system learns stable altruistic behaviors, so achieving optimal (or near-to-optimal) performances in unknown and changing environments.

  7. Positive solutions of quasilinear parabolic systems with Dirichlet boundary condition

    NASA Astrophysics Data System (ADS)

    Pao, C. V.; Ruan, W. H.

    Coupled systems for a class of quasilinear parabolic equations and the corresponding elliptic systems, including systems of parabolic and ordinary differential equations are investigated. The aim of this paper is to show the existence, uniqueness, and asymptotic behavior of time-dependent solutions. Also investigated is the existence of positive maximal and minimal solutions of the corresponding quasilinear elliptic system. The elliptic operators in both systems are allowed to be degenerate in the sense that the density-dependent diffusion coefficients D(u) may have the property D(0)=0 for some or all i=1,…,N, and the boundary condition is u=0. Using the method of upper and lower solutions, we show that a unique global classical time-dependent solution exists and converges to the maximal solution for one class of initial functions and it converges to the minimal solution for another class of initial functions; and if the maximal and minimal solutions coincide then the steady-state solution is unique and the time-dependent solution converges to the unique solution. Applications of these results are given to three model problems, including a scalar polynomial growth problem, a coupled system of polynomial growth problem, and a two component competition model in ecology.

  8. Extensions to Dynamic System Simulation of Fissile Solution Systems

    SciTech Connect

    Klein, Steven Karl; Bernardin, John David; Kimpland, Robert Herbert; Spernjak, Dusan

    2015-08-24

    Previous reports have documented the results of applying dynamic system simulation (DSS) techniques to model a variety of fissile solution systems. The SUPO (Super Power) aqueous homogeneous reactor (AHR) was chosen as the benchmark for comparison of model results to experimental data for steadystate operation.1 Subsequently, DSS was applied to additional AHR to verify results obtained for SUPO and extend modeling to prompt critical excursions, ramp reactivity insertions of various magnitudes and rate, and boiling operations in SILENE and KEWB (Kinetic Experiment Water Boiler).2 Additional models for pressurized cores (HRE: Homogeneous Reactor Experiment), annular core geometries, and accelerator-driven subcritical systems (ADAHR) were developed and results reported.3 The focus of each of these models is core dynamics; neutron kinetics, thermal hydraulics, radiolytic gas generation and transport are coupled to examine the time-based evolution of these systems from start-up through transition to steady-state. A common characteristic of these models is the assumption that (a) core cooling system inlet temperature and flow and (b) plenum gas inlet pressure and flow are held constant; no external (to core) component operations that may result in dynamic change to these parameters are considered. This report discusses extension of models to include explicit reference to cooling structures and radiolytic gas handling. The accelerator-driven subcritical generic system model described in References 3 and 4 is used as a basis for this extension.

  9. A Multi-Agent Emotion Generating System for Mobile Robots System

    NASA Astrophysics Data System (ADS)

    Nair, Shivashankar B.; Kim, Dong Hwa

    Emotions are a complex phenomenon and are in constant research for so long. Emotions can be presupposed as a dynamic association of cells on elicitation. The use of agents for emotions generation and emotion modeling are on the rise in the recent years. In this work, we propose a dynamic emotion generation system based on multiple agents. A Multi-Agent System (MAS) to generate emotions targeted towards a mobile robot has been implemented. The agent-robot communication is still being investigated. An illustration of the use of this emotion generation module is explained in the context of the emotion system. Some ancillary investigations performed in using mobile robots for localization and terrain mapping have also been described.

  10. Use of Monsel’s Solution to Treat Obstetrical Hemorrhage: A Review and Comparison to Other Topical Hemostatic Agents

    PubMed Central

    MILLER, Devin T.; ROQUE, Dana M.; SANTIN, Alessandro D.

    2014-01-01

    Peripartum hemorrhage accounts for 8% of maternal deaths in the United States, and nearly 27% worldwide. A growing need exists for tactics to spare morbidity given a rise of abnormal placentation that contributes to excessive blood loss at the time of delivery. Approaches such as compression sutures, balloon tamponade, and pelvic artery embolization are not without side effects and potential implications for future fertility. The use of topical hemostatic agents has become widespread in gynecologic and obstetric surgery despite a paucity of distinct studies in the field, and may allow providers to increasingly avoid cesarean hysterectomy. A variety of topical hemostatic agents exist along a wide cost continuum, each characterized by specific efficacy, advantages, drawbacks, and often gaps in long-term data to support safety and impact on future fertility. Herein, we comprehensively review these agents and illustrate a non-traditional use of Monsel’s solution applied directly to the placental bed in a case of focal placenta accreta. This ultimately contributed to successful uterine preservation with no known adverse sequelae. Monsel’s solution may have a role in establishing hemostasis in the setting of abnormal placentation, and may be a particularly attractive alternative in resource-poor nations. PMID:25577672

  11. Relaxivity of Gd-based contrast agents on X nuclei with long intrinsic relaxation times in aqueous solutions

    PubMed Central

    van Heeswijk, Ruud B.; Laus, Sabrina; Morgenthaler, Florence D.; Gruetter, Rolf

    2007-01-01

    The relaxivity of commercially available gadolinium-based contrast agents was studied for X-nuclei resonances with long intrinsic relaxation times ranging between 6 and several hundred seconds. Omniscan in pure 13C formic acid had a relaxivity of 2.9 mM-1 s-1, whereas its relaxivity on glutamate C1 and C5 in aqueous solution was ∼0.5 mM-1 s-1. Both relaxivities allow the preparation of solutions with a predetermined short T1 suggest that in vitro substantial sensitivity gains in their measurement can be achieved. 6Li has a long intrinsic relaxation time, on the order of several minutes, which was strongly affected by the contrast agents. Relaxivity ranged from ∼0.1 mM-1 s-1 for Omniscan to 0.3 for Magnevist, whereas the relaxivity of Gd-DOTP was at 11 mM-1 s-1 two orders of magnitude higher. Overall these experiments suggest that the presence of 0.1-10 μM contrast agents should be detectable, provided sufficient sensitivity is available, such as that afforded by hyperpolarization, recently introduced to in vivo imaging. PMID:17448617

  12. Use of Monsel solution to treat obstetrical hemorrhage: a review and comparison to other topical hemostatic agents.

    PubMed

    Miller, Devin T; Roque, Dana M; Santin, Alessandro D

    2015-06-01

    Peripartum hemorrhage accounts for 8% of maternal deaths in the United States, and nearly 27% worldwide. A growing need exists for tactics to spare morbidity given a rise of abnormal placentation that contributes to excessive blood loss at the time of delivery. Approaches such as compression sutures, balloon tamponade, and pelvic artery embolization are not without side effects and potential implications for future fertility. The use of topical hemostatic agents has become widespread in gynecologic and obstetric surgery despite a paucity of distinct studies in the field, and may allow providers to increasingly avoid cesarean hysterectomy. A variety of topical hemostatic agents exist along a wide cost continuum, each characterized by specific efficacy, advantages, drawbacks, and often gaps in long-term data to support safety and impact on future fertility. Herein, we comprehensively review these agents and illustrate a nontraditional use of Monsel solution applied directly to the placental bed in a case of focal placenta accreta. This ultimately contributed to successful uterine preservation with no known adverse sequelae. Monsel solution may have a role in establishing hemostasis in the setting of abnormal placentation, and may be a particularly attractive alternative in resource-poor nations.

  13. Agent-Based Mediation and Cooperative Information Systems

    SciTech Connect

    PHILLIPS, LAURENCE R.; LINK, HAMILTON E.; GOLDSMITH, STEVEN Y.

    2002-06-02

    This report describes the results of research and development in the area of communication among disparate species of software agents. The two primary elements of the work are the formation of ontologies for use by software agents and the means by which software agents are instructed to carry out complex tasks that require interaction with other agents. This work was grounded in the areas of commercial transport and cybersecurity.

  14. AIMS: An Agent-Based Information Management System in JBI-like Environments

    DTIC Science & Technology

    2007-05-01

    Information Management System, to manage the quality of information in JBI-like environments, e.g., information trustworthiness. In our approach, each operator is associated with a software agent, called client agent. The client agent enables its operator to interact with the JBI repository via the services of query, publish, and subscribe. Moreover, the client agent collaborates with other agents to assess and learn the trustworthiness of information and the reliabilities of corresponding data sources from its pedigree and the feedback from

  15. Pharmacologic management of periodontal diseases using systemically administered agents.

    PubMed

    Mariotti, A; Monroe, P J

    1998-04-01

    Since the establishment of bacteria-laden plaque as a causative agent in gingivitis, the search for specific bacteria that induce different types of periodontitis has generated extensive research. In contrast to many other microbial-induced disorders, the specific periodontal pathogen(s) has not been identified to date. Therefore, the search for an effective systemic agent to prevent the loss of attachment through the selective reduction of known periodontal pathogens has remained elusive. It is not surprising then that antibiotics are not used solely to manage periodontal diseases but rather as an adjunct to the mechanical débridement of root surfaces in select periodontal diseases. Further, the sole use of antibiotics in patients with adult periodontitis (or those who exhibit signs of inflammation but are periodontally stable) has shown little benefit and only increases the chance of microbial resistance to antibiotics. Despite these limitations, considerable progress in antibiotic therapy has delivered regimens that enhance the effectiveness of conventional therapy. In contrast to traditional antimicrobial therapy, new treatment modalities have begun to focus on modulating the responses of host cells to bacteria rather than modulating only the bacteria. Current drugs used to regulate host cells inhibit the cyclooxygenase pathway, reduce the activity of metalloproteinases, or inactivate bone resorptive cells (see Table 1). Although these drugs offer great potential to modulate a variety of mammalian cells, a notable and consequential limitation of these agents is a lack of specificity. Inflammation, bone metabolism, and connective tissue metabolism are two-edged swords; all are necessary for the homeostasis of the tissue, but some or all may also be involved in the pathologic destruction of that same tissue. Hence, drugs that inhibit destruction of the connective tissue in one site of the periodontium also interfere with wound healing at another. As a result of

  16. Autonomous Decentralized Voltage Profile Control of Super Distributed Energy System using Multi-agent Technology

    NASA Astrophysics Data System (ADS)

    Tsuji, Takao; Hara, Ryoichi; Oyama, Tsutomu; Yasuda, Keiichiro

    A super distributed energy system is a future energy system in which the large part of its demand is fed by a huge number of distributed generators. At one time some nodes in the super distributed energy system behave as load, however, at other times they behave as generator - the characteristic of each node depends on the customers' decision. In such situation, it is very difficult to regulate voltage profile over the system due to the complexity of power flows. This paper proposes a novel control method of distributed generators that can achieve the autonomous decentralized voltage profile regulation by using multi-agent technology. The proposed multi-agent system employs two types of agent; a control agent and a mobile agent. Control agents generate or consume reactive power to regulate the voltage profile of neighboring nodes and mobile agents transmit the information necessary for VQ-control among the control agents. The proposed control method is tested through numerical simulations.

  17. Multi-agent system as a platform for management of medical documentation.

    PubMed

    Lhotska, Lenka

    2007-01-01

    The paper is focused on description of an ongoing project of a pilot study and implementation of a multi-agent system for management of medical documentation in a hospital. First we analyzed the problem and divided it into four groups of tasks: storing and retrieving stored data, user interaction, data archiving, and system security. All these tasks are performed by corresponding agents, namely user interface agent, database agent, archive agent, and security agent. Communication between the agents is a crucial point of the system operation. The system has been designed as an open system and we assume that it will be extended by additional agents with new functions, e.g. decision support, biomedical signal evaluation, laboratory test evaluation.

  18. Oscillatory traveling wave solutions to an attractive chemotaxis system

    NASA Astrophysics Data System (ADS)

    Li, Tong; Liu, Hailiang; Wang, Lihe

    2016-12-01

    This paper investigates oscillatory traveling wave solutions to an attractive chemotaxis system. The convective part of this system changes its type when crossing a parabola in the phase space. The oscillatory nature of the traveling wave comes from the fact that one far-field state is in the elliptic region and another in the hyperbolic region. Such traveling wave solutions are shown to be linearly unstable. Detailed construction of some traveling wave solutions is presented.

  19. iMuseumA: An Agent-Based Context-Aware Intelligent Museum System

    PubMed Central

    Ayala, Inmaculada; Amor, Mercedes; Pinto, Mónica; Fuentes, Lidia; Gámez, Nadia

    2014-01-01

    Currently, museums provide their visitors with interactive tour guide applications that can be installed in mobile devices and provide timely tailor-made multimedia information about exhibits on display. In this paper, we argue that mobile devices not only could provide help to visitors, but also to museum staff. Our goal is to integrate, within the same system, multimedia tour guides with the management facilities required by museums. In this paper, we present iMuseumA (intelligent museum with agents), a mobile-based solution to customize visits and perform context-aware management tasks. iMuseumA follows an agent-based approach, which makes it possible to interact easily with the museum environment and make decisions based on its current status. This system is currently deployed in the Museum of Informatics at the Informatics School of the University of Málaga, and its main contributions are: (i) a mobile application that provides management facilities to museum staff by means of sensing and processing environmental data; (ii) providing an integrated solution for visitors, tour guides and museum staff that allows coordination and communication enrichment among different groups of users; (iii) using and benefiting from group communication for heterogeneous groups of users that can be created on demand. PMID:25390409

  20. L1 limit solutions for control systems

    NASA Astrophysics Data System (ADS)

    Aronna, M. Soledad; Rampazzo, Franco

    2015-02-01

    For a control Cauchy problemsolutions, we believe that various theoretical issues call for a unified notion of trajectory. For instance, this is the case of optimal control problems, possibly with state and endpoint constraints, for which no extra assumptions (like e.g. coercivity, bounded variation, commutativity) are made in advance.

  1. COTS Multicore Processors in Avionics Systems: Challenges and Solutions

    DTIC Science & Technology

    2015-01-06

    COTS Multicore Processors in Avionics Systems: Challenges and Solutions Dionisio de Niz Bjorn Andersson and Lutz Wrage dionisio @sei.cmu.edu...Avionics Systems: Challenges and Solutions 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) Wrage / Dionisio de Niz Bjorn

  2. Thiophene Scaffold as Prospective Central Nervous System Agent: A Review.

    PubMed

    Deep, Aakash; Narasimhan, Balasubramanian; Aggarwal, Swati; Kaushik, Dhirender; Sharma, Arun K

    2016-01-01

    Heterocyclic compounds are extensively dispersed in nature and are vital for life. Various investigational approaches towards Structural Activity Relationship that focus upon the exploration of optimized candidates have become vastly important. Literature studies tell that for a series of compounds that are imperative in industrial and medicinal chemistry, thiophene acts as parent. Among various classes of heterocyclic compounds that have potential central nervous system activity, thiophene is the most important one. In the largely escalating chemical world of heterocyclic compounds showing potential pharmacological character, thiophene nucleus has been recognized as the budding entity. Seventeen Papers were included in this review article to define the central nervous system potential of thiophene. This review article enlightens the rationalized use and scope of thiophene scaffold as novel central nervous system activity such as anticonvulsant, acetylcholinesterase inhibitor, cyclin-dependent kinase 5 (cdk5/p25) inhibitors, CNS depressant, capability to block norepinephrine, serotonin and dopamine reuptake by their respective transporters etc. The Finding of this review confirm the importance of thiophene scaffold as potential central nervous system agents. From this outcome, ideas for future molecular modifications leading to the novel derivatives with better constructive pharmacological potential may be derived.

  3. Agent-based intelligent medical diagnosis system for patients.

    PubMed

    Zhang, Yingfeng; Liu, Sichao; Zhu, Zhenfei; Si, Shubin

    2015-01-01

    According to the analysis of the challenges faced by the current public health circumstances such as the sharp increase in elderly patients, limited medical personnel, resources and technology, the agent-based intelligent medical diagnosis system for patients (AIMDS) is proposed in this research. Based on advanced sensing technology and professional medical knowledge, the AIMDS can output the appropriate medical prescriptions and food prohibition when the physical signs and symptoms of the patient are inputted. Three core modules are designed include sensing module, intuition-based fuzzy set theory/medical diagnosis module, and medical knowledge module. The result shows that the optimized prescription can reach the desired level, with great curative effect for patient disease, through a case study simulation. The presented AIMDS can integrate sensor technique and intelligent medical diagnosis methods to make an accurate diagnosis, resulting in three-type of optimized descriptions for patient selection.

  4. National Institute for Rocket Propulsion Systems (NIRPS): Solutions Facilitator

    NASA Technical Reports Server (NTRS)

    Brown, Tom

    2011-01-01

    National Institute for Rocket Propulsion Systems (NIRPS) "Solutions" plans to enable our nation's future in rocket propulsion systems by leveraging existing skills and capabilities to support industry's future needs

  5. 1H NMR analysis of complexation of hydrotropic agents nicotinamide and caffeine with aromatic biologically active molecules in aqueous solution

    NASA Astrophysics Data System (ADS)

    Lantushenko, Anastasia O.; Mukhina, Yulia V.; Veselkov, Kyrill A.; Davies, David B.; Veselkov, Alexei N.

    2004-07-01

    NMR spectroscopy has been used to elucidate the molecular mechanism of solubilization action of hydrotropic agents nicotinamide (NA) and caffeine (CAF). Hetero-association of NA with riboflavine-mononucleotide (FMN) and CAF with low soluble in aqueous solution synthetic analogue of antibiotic actinomycin D, actinocyl-bis-(3-dimethylaminopropyl) amine (Actill), has been investigated by 500 MHz 1H NMR spectroscopy. Concentration and temperature dependences of proton chemical shifts have been analysed in terms of a statistical-thermodynamic model of indefinite self- and heteroassociation of aromatic molecules. The obtained results enable to conclude that NA-FMN and CAF-Actill intermolecular complexes are mainly stabilized by the stacking interactions of the aromatic chromophores. Hetero-association of the investigated molecules plays an important role in solubilization of aromatic drugs by hydrotropic agents nicotinamide and caffeine.

  6. Agents Control in Intelligent Learning Systems: The Case of Reactive Characteristics

    ERIC Educational Resources Information Center

    Laureano-Cruces, Ana Lilia; Ramirez-Rodriguez, Javier; de Arriaga, Fernando; Escarela-Perez, Rafael

    2006-01-01

    Intelligent learning systems (ILSs) have evolved in the last few years basically because of influences received from multi-agent architectures (MAs). Conflict resolution among agents has been a very important problem for multi-agent systems, with specific features in the case of ILSs. The literature shows that ILSs with cognitive or pedagogical…

  7. Agents Control in Intelligent Learning Systems: The Case of Reactive Characteristics

    ERIC Educational Resources Information Center

    Laureano-Cruces, Ana Lilia; Ramirez-Rodriguez, Javier; de Arriaga, Fernando; Escarela-Perez, Rafael

    2006-01-01

    Intelligent learning systems (ILSs) have evolved in the last few years basically because of influences received from multi-agent architectures (MAs). Conflict resolution among agents has been a very important problem for multi-agent systems, with specific features in the case of ILSs. The literature shows that ILSs with cognitive or pedagogical…

  8. Interacting agents through a web-based health serviceflow management system.

    PubMed

    Leonardi, Giorgio; Panzarasa, Silvia; Quaglini, Silvana; Stefanelli, Mario; van der Aalst, Wil M P

    2007-10-01

    The management of chronic and out-patients is a complex process which requires the cooperation of different agents belonging to several organizational units. Patients have to move to different locations to access the necessary services and to communicate their health status data. From their point of view there should be only one organization (Virtual Health-Care Organization) which provides both virtual and face-to-face encounters. In this paper we propose the Serviceflow Management System as a solution to handle these information and the communication requirements. The system consists of: (a) the model of the care process represented as a Serviceflow and developed using the Workflow Management System YAWL; (b) an organizational ontology representing the VHCO; and (c) agreements and commitments between the parties defined in a contract (represented as an XML document). On the basis of a general architecture we present an implementation in the area of Diabetes management.

  9. [Norfloxacin Solution Degradation Under Ultrasound, Potassium Persulfate Collaborative System].

    PubMed

    Wei, Hong; Shi, Jing-zhuan; Li, Jia-lin; Li, Ke-bin; Zhao, Lin; Han, Kai

    2015-11-01

    High oxidative sulfate radicals can be produced by potassium persulfate (K2S2O8). The integrated effect of ultrasonic and K2S2O8, on norfloxacin degradation was investigated. The experimental parameters such as K2S2O8 concentration, norfloxacin initial concentration, initial pH value, free radicals quenching agents such as methanol and tert-butyl on norfloxacin degradation were discussed. The results indicated that ultrasonic/K2S2O8, system had an obvious degradation and mineralization effect on norfloxacin. Norfloxacin removal efficiencies were 3.2 and 8.9 times in ultrasonic/K2S2O8 system than those in single K252O8 and ultrasonic oxidation system, respectively. And the reaction followed the first-order kinetics. Norfloxacin removal efficiency varied gently with K2S2O8 concentration. Solution initial pH had a significant effect on norfloxacin degradation, which was attributed to the different oxidizing species under different pH values. The radicals were sulfate radicals under acidic and neutral conditions, and was the combination of sulfate and hydroxyl radicals under alkaline conditions. TOC and agar diffusion test with E. coli showed that 49.12% norfloxacin was mineralized and antibacterial activity was completely removed, with the diameter of E. coli inhibition zone decreased from 45 mm to 14 mm (filter paper diameter). The result implied that ultrasound/K2S2O8 showed promising results as a possible application for treatment of norfloxacin antibiotics wastewater.

  10. Solution mining dawsonite from hydrocarbon containing formations with a chelating agent

    DOEpatents

    Vinegar, Harold J.

    2009-07-07

    A method for treating an oil shale formation comprising dawsonite includes providing heat from one or more heaters to the formation to heat the formation. Hydrocarbon fluids are produced from the formation. At least some dawsonite in the formation is decomposed with the provided heat. A chelating agent is provided to the formation to dissolve at least some dawsonite decomposition products. The dissolved dawsonite decomposition products are produced from the formation.

  11. Distributed decision-making in electric power system transmission maintenance scheduling using multi-agent systems (MAS)

    NASA Astrophysics Data System (ADS)

    Zhang, Zhong

    In this work, motivated by the need to coordinate transmission maintenance scheduling among a multiplicity of self-interested entities in restructured power industry, a distributed decision support framework based on multiagent negotiation systems (MANS) is developed. An innovative risk-based transmission maintenance optimization procedure is introduced. Several models for linking condition monitoring information to the equipment's instantaneous failure probability are presented, which enable quantitative evaluation of the effectiveness of maintenance activities in terms of system cumulative risk reduction. Methodologies of statistical processing, equipment deterioration evaluation and time-dependent failure probability calculation are also described. A novel framework capable of facilitating distributed decision-making through multiagent negotiation is developed. A multiagent negotiation model is developed and illustrated that accounts for uncertainty and enables social rationality. Some issues of multiagent negotiation convergence and scalability are discussed. The relationships between agent-based negotiation and auction systems are also identified. A four-step MAS design methodology for constructing multiagent systems for power system applications is presented. A generic multiagent negotiation system, capable of inter-agent communication and distributed decision support through inter-agent negotiations, is implemented. A multiagent system framework for facilitating the automated integration of condition monitoring information and maintenance scheduling for power transformers is developed. Simulations of multiagent negotiation-based maintenance scheduling among several independent utilities are provided. It is shown to be a viable alternative solution paradigm to the traditional centralized optimization approach in today's deregulated environment. This multiagent system framework not only facilitates the decision-making among competing power system entities, but

  12. Microfluidic-Based Robotic Sampling System for Radioactive Solutions

    SciTech Connect

    Jack D. Law; Julia L. Tripp; Tara E. Smith; Veronica J. Rutledge; Troy G. Garn; John Svoboda; Larry Macaluso

    2014-02-01

    A novel microfluidic based robotic sampling system has been developed for sampling and analysis of liquid solutions in nuclear processes. This system couples the use of a microfluidic sample chip with a robotic system designed to allow remote, automated sampling of process solutions in-cell and facilitates direct coupling of the microfluidic sample chip with analytical instrumentation. This system provides the capability for near real time analysis, reduces analytical waste, and minimizes the potential for personnel exposure associated with traditional sampling methods. A prototype sampling system was designed, built and tested. System testing demonstrated operability of the microfluidic based sample system and identified system modifications to optimize performance.

  13. True Anomalous Osmosis in Multi-Solute Model Membrane Systems

    PubMed Central

    Grim, Eugene; Sollner, Karl

    1960-01-01

    The transport of liquid across charged porous membranes separating two electrolytic solutions of different composition consists of both a normal and an anomalous osmotic component. Anomalous osmosis does not occur with electroneutral membranes. Thus, with membranes which can be charged and discharged reversibly, normal osmosis can be measured with the membrane in the electroneutral state, and normal together with anomalous osmosis with the membrane in a charged state, the difference between these two effects being the true anomalous osmosis. Data are presented on the osmotic effects across an oxyhemoglobin membrane in the uncharged state at pH 6.75 and in two charged states, positive at pH 4.0 and negative at pH 10.0, in multi-solute systems with 0.2 and 0.4 osmolar solutions of a variety of electrolytes and of glucose against solutions of other solutes of the same, one-half, and twice these osmolarities. In the simpler systems the magnitude of the true anomalous osmosis can be predicted semiquantitatively by reference to appropriate single-solute systems. In isoosmolar systems with two electrolytic solutions the anomalous osmotic flow rates may reach 300 µl./cm.2 hr. and more; systems with electrolytic solutions against solutions of glucose can produce twice this rate. These fluxes are of the same order of magnitude as the liquid transport rates across such living structures as the mucosa of dog gall bladder, ileum, and urinary bladder. PMID:13708691

  14. Minimal Solution of Singular LR Fuzzy Linear Systems

    PubMed Central

    Nikuie, M.; Ahmad, M. Z.

    2014-01-01

    In this paper, the singular LR fuzzy linear system is introduced. Such systems are divided into two parts: singular consistent LR fuzzy linear systems and singular inconsistent LR fuzzy linear systems. The capability of the generalized inverses such as Drazin inverse, pseudoinverse, and {1}-inverse in finding minimal solution of singular consistent LR fuzzy linear systems is investigated. PMID:24737977

  15. Minimal solution of singular LR fuzzy linear systems.

    PubMed

    Nikuie, M; Ahmad, M Z

    2014-01-01

    In this paper, the singular LR fuzzy linear system is introduced. Such systems are divided into two parts: singular consistent LR fuzzy linear systems and singular inconsistent LR fuzzy linear systems. The capability of the generalized inverses such as Drazin inverse, pseudoinverse, and {1}-inverse in finding minimal solution of singular consistent LR fuzzy linear systems is investigated.

  16. The role of multivalent metal cations and organic complexing agents in bitumen-mineral interactions in aqueous solutions

    NASA Astrophysics Data System (ADS)

    Gan, Weibing

    A systematic investigation was carried out to study the interactions between bitumen (or hexadecane) and minerals (quartz, kaolinite and illite) in aqueous solutions containing multivalent metal cations Ca2+, Mg2+ and Fe2+/Fe3+, in the absence and presence of organic complexing agents (oxalic acid, EDTA and citric acid). A range of experimental techniques, including coagulation measurement, visualization of bitumen-mineral attachment, metal ion adsorption measurement, zeta potential measurement, Fourier-transform infrared spectroscopy and X-ray photoelectron spectroscopic analyses, were employed in the investigation. Free energy changes of adsorption of metal cations on the minerals and bitumen were evaluated using the James & Healy thermodynamic model. Total interaction energies between the minerals and bitumen were calculated using classical DLVO theory. It was observed that while the tested minerals showed varying degrees of mutual-coagulation with bitumen (or hexadecane), the presence of the multivalent metal cations could prominently increase the mutual coagulation. It was also found that such enhancement of the mutual coagulation was only significant when the metal cations formed first-order hydroxyl complexes (such as CaOH +, MgOH+, etc.) or metal hydroxides (such as Fe(OH) 3, Mg(OH)2, etc.). Therefore, the increase of the bitumen-mineral mutual coagulation by the metal cations was strongly pH dependent. Organic complexing agents (oxalic acid, citric acid and EDTA) used in this study, citric acid in particular, significantly reduced or virtually eliminated the mutual coagulation between bitumen (or hexadecane) and minerals caused by metal cations Ca2+, Mg2+, Fe 2+ and Fe3+. Due to its ability to substantially lower the mutual coagulation between bitumen and mineral particles, citric acid was found the most effective in improving bitumen-mineral liberation in solutions containing the multivalent metal cations at pH 8--10. In small scale flotation experiments

  17. Agent-based Systems Key Enabler for the Army’s Future Force

    DTIC Science & Technology

    2003-10-04

    application areas for intelligent be used to support the development of new, revolutionary agent technology that will enable the US Army to rapidly...defining and state of the art information technologies to interpret and implementing agent-based solutions for other echelons and understand the evolving...apply intelligent agent technology to assist in the "Zone of Intel". This reach back capability to data collected information processing, management and

  18. Model Checking Degrees of Belief in a System of Agents

    NASA Technical Reports Server (NTRS)

    Raimondi, Franco; Primero, Giuseppe; Rungta, Neha

    2014-01-01

    Reasoning about degrees of belief has been investigated in the past by a number of authors and has a number of practical applications in real life. In this paper we present a unified framework to model and verify degrees of belief in a system of agents. In particular, we describe an extension of the temporal-epistemic logic CTLK and we introduce a semantics based on interpreted systems for this extension. In this way, degrees of beliefs do not need to be provided externally, but can be derived automatically from the possible executions of the system, thereby providing a computationally grounded formalism. We leverage the semantics to (a) construct a model checking algorithm, (b) investigate its complexity, (c) provide a Java implementation of the model checking algorithm, and (d) evaluate our approach using the standard benchmark of the dining cryptographers. Finally, we provide a detailed case study: using our framework and our implementation, we assess and verify the situational awareness of the pilot of Air France 447 flying in off-nominal conditions.

  19. A generic task-driven multi-agent telemedicine system.

    PubMed

    Nageba, Ebrahim; Fayn, Jocelyne; Rubel, Paul

    2007-01-01

    Pervasive Telemedicine is an emerging research discipline, which focuses on the development and the application of ubiquitous computing technology for healthcare purposes. However, the current telemedicine systems lack to be self adaptable to handle different types of data such as vital biosignals, images, video and textual data. In addition, they do not use the full capabilities of the computing devices on which they run. Unfortunately, the existing telemedicine systems do not pay enough attention to the quality level of their offered services nor offer adequate resources management for meeting bandwidth and end-to-end communication delays. In this paper we propose an information and communication architecture of a generic telemedicine system based on a knowledge base and intelligent agents interacting each with the other in a synergetic way to perform several medical tasks for a high level of quality of service (QoS). The medical assistance to skiers and high mountains resorts residents will be used in particular as an example of applicability scenario and models personalization.

  20. Microscopic study of crystal growth in cryopreservation agent solutions and water.

    PubMed

    Tao, Le-Ren; Hua, Tse-Chao

    2002-10-01

    Ice formation inside or outside cells during cryopreservation is evidently the main factor of cryoinjury to cells. In the study described here a high voltage DC electric field and a cryomicroscopic stage were used to test DMSO and NaCl solutions under electric field strengths ranging from 83 kV/m to 320 kV/m. Dendritic ice crystals became asymmetric when the electric field was activated. This change in the ice crystal shape was more pronounced in the ionic NaCl solution. In addition, ice growth of distilled water without an electric field was tested under different cooling rates.

  1. Multi-target pursuit formation of multi-agent systems

    NASA Astrophysics Data System (ADS)

    Yan, Jing; Guan, Xin-Ping; Luo, Xiao-Yuan

    2011-01-01

    The main goal of this paper is to design a team of agents that can accomplish multi-target pursuit formation using a developed leader—follower strategy. It is supposed that every target can accept a certain number of agents. First, each agent can automatically choose its target based on the distance from the agent to the target and the number of agents accepted by the target. In view of the fact that all agents are randomly dispersed in the workplace at the initial time, we present a numbering strategy for them. During the movement of agents, not every agent can always obtain pertinent state information about the targets. So, a developed leader—follower strategy and a pursuit formation algorithm are proposed. Under the proposed method, agents with the same target can maintain a circle formation. Furthermore, it turns out that the pursuit formation algorithm for agents to the desired formation is convergent. Simulation studies are provided to illustrate the effectiveness of the proposed method.

  2. Adaptive containment control of nonlinear multi-agent systems with non-identical agents

    NASA Astrophysics Data System (ADS)

    Haghshenas, Hamed; Badamchizadeh, Mohammad Ali; Baradarannia, Mahdi

    2015-08-01

    This paper addresses the containment control problem for a group of non-identical agents, where the dynamics of agents are supposed to be nonlinear with unknown parameters and parameterised by some functions. In controller design approach for each follower, adaptive control and Lyapunov theory are utilised as the main control strategies to guarantee the convergence of all non-identical followers to the dynamic convex hull formed by the leaders. The design of distributed adaptive controllers is based on the exchange of neighbourhood errors among the agents. For analysis of containment control problem, a new formulation has been developed using M-matrices. The validity of theoretical results are demonstrated through an example.

  3. Ant system: optimization by a colony of cooperating agents.

    PubMed

    Dorigo, M; Maniezzo, V; Colorni, A

    1996-01-01

    An analogy with the way ant colonies function has suggested the definition of a new computational paradigm, which we call ant system (AS). We propose it as a viable new approach to stochastic combinatorial optimization. The main characteristics of this model are positive feedback, distributed computation, and the use of a constructive greedy heuristic. Positive feedback accounts for rapid discovery of good solutions, distributed computation avoids premature convergence, and the greedy heuristic helps find acceptable solutions in the early stages of the search process. We apply the proposed methodology to the classical traveling salesman problem (TSP), and report simulation results. We also discuss parameter selection and the early setups of the model, and compare it with tabu search and simulated annealing using TSP. To demonstrate the robustness of the approach, we show how the ant system (AS) can be applied to other optimization problems like the asymmetric traveling salesman, the quadratic assignment and the job-shop scheduling. Finally we discuss the salient characteristics-global data structure revision, distributed communication and probabilistic transitions of the AS.

  4. Langevin processes, agent models and socio-economic systems

    NASA Astrophysics Data System (ADS)

    Richmond, Peter; Sabatelli, Lorenzo

    2004-05-01

    We review some approaches to the understanding of fluctuations of financial asset prices. Our approach builds on the development of a simple Langevin equation that characterises stochastic processes. This provides a unifying approach that allows first a straightforward description of the early approaches of Bachelier. We generalize the approach to stochastic equations that model interacting agents. The agent models recently advocated by Marsilli and Solomon are motivated. Using a simple change of variable, we show that the peer pressure model of Marsilli and the wealth dynamics model of Solomon are essentially equivalent. The methods are further shown to be consistent with a global free energy functional that invokes an entropy term based on the Boltzmann formula. There follows a brief digression on the Heston model that extends the simple model to one that, in the language of physics, exhibits a temperature this is subject to stochastic fluctuations. Mathematically the model corresponds to a Feller process. Dragulescu and Yakovenko have shown how the model yields some of the stylised features of asset prices. A more recent approach by Michael and Johnson maximised a Tsallis entropy function subject to simple constraints. They obtain a distribution function for financial returns that exhibits power law tails and which can describe the distribution of returns not only over low but also high frequencies (minute by minute) data for the Dow Jones index. We show how this approach can be developed from an agent model, where the simple Langevin process is now conditioned by local rather than global noise. Such local noise may of course be the origin of speculative frenzy or herding in the market place. The approach yields a BBGKY type hierarchy of equations for the system correlation functions. Of especial interest is that the results can be obtained from a new free energy functional similar to that mentioned above except that a Tsallis like entropy term replaces the

  5. Suitability of Agent Technology for Military Command and Control in the Future Combat System Environment

    SciTech Connect

    Potok, TE

    2003-02-13

    The U.S. Army is faced with the challenge of dramatically improving its war fighting capability through advanced technologies. Any new technology must provide significant improvement over existing technologies, yet be reliable enough to provide a fielded system. The focus of this paper is to assess the novelty and maturity of agent technology for use in the Future Combat System (FCS). The FCS concept represents the U.S. Army's ''mounted'' form of the Objective Force. This concept of vehicles, communications, and weaponry is viewed as a ''system of systems'' which includes net-centric command and control (C{sup 2}) capabilities. This networked C{sup 2} is an important transformation from the historically centralized, or platform-based, C{sup 2} function since a centralized command architecture may become a decision-making and execution bottleneck, particularly as the pace of war accelerates. A mechanism to ensure an effective network-centric C{sup 2} capacity (combining intelligence gathering and analysis available at lower levels in the military hierarchy) is needed. Achieving a networked C{sup 2} capability will require breakthroughs in current software technology. Many have proposed the use of agent technology as a potential solution. Agents are an emerging technology, and it is not yet clear whether it is suitable for addressing the networked C{sup 2} challenge, particularly in satisfying battlespace scalability, mobility, and security expectations. We have developed a set of software requirements for FCS based on military requirements for this system. We have then evaluated these software requirements against current computer science technology. This analysis provides a set of limitations in the current technology when applied to the FCS challenge. Agent technology is compared against this set of limitations to provide a means of assessing the novelty of agent technology in an FCS environment. From this analysis we find that existing technologies will not

  6. Solvation agent for disulfide precipitates from inhibited glycol-water solutions

    NASA Technical Reports Server (NTRS)

    Taylor, M. F.

    1971-01-01

    Small additions /0.01 percent or less/ of triethanoloamine sodium sulfite adduct to mercapto benzothiazole inhibited glycol water heat transfer solutions containing disulfide precipitate produce marked reduction in amount of precipitate. Adduct is useful as additive in glycol base antifreezes and coolants.

  7. Evaluation of decontamination efficacy of cleaning solutions on stainless steel and glass surfaces contaminated by 10 antineoplastic agents.

    PubMed

    Queruau Lamerie, Thomas; Nussbaumer, Susanne; Décaudin, Bertrand; Fleury-Souverain, Sandrine; Goossens, Jean-François; Bonnabry, Pascal; Odou, Pascal

    2013-05-01

    The handling of antineoplastic agents results in chronic surface contamination that must be minimized and eliminated. This study was designed to assess the potential of several chemical solutions to decontaminate two types of work surfaces that were intentionally contaminated with antineoplastic drugs. A range of solutions with variable physicochemical properties such as their hydrophilic/hydrophobic balance, oxidizing power, desorption, and solubilization were tested: ultrapure water, isopropyl alcohol, acetone, sodium hypochlorite, and surfactants such as dishwashing liquid (DWL), sodium dodecyl sulfate (SDS), Tween 40, and Span 80. These solutions were tested on 10 antineoplastic drugs: cytarabine, gemcitabine, methotrexate, etoposide phosphate, irinotecan, cyclophosphamide, ifosfamide, doxorubicin, epirubicin, and vincristine. To simulate contaminated surfaces, these molecules (200ng) were deliberately spread onto two types of work surfaces: stainless steel and glass. Recovered by wiping with a specific aqueous solvent (acetonitrile/HCOOH; 20/0.1%) and an absorbent wipe (Whatman 903®), the residual contamination was quantified using high-performance liquid chromatography (HPLC) coupled to mass spectrometry. To compare all tested cleaning solutions, a performance value of effectiveness was determined from contamination residues of the 10 drugs. Sodium hypochlorite showed the highest overall effectiveness with 98% contamination removed. Ultrapure water, isopropyl alcohol/water, and acetone were less effective with effectiveness values of 76.8, 80.7, and 40.4%, respectively. Ultrapure water was effective on most hydrophilic molecules (97.1% for cytarabine), while on the other hand, isopropyl alcohol/water (70/30, vol/vol) was effective on the least hydrophilic ones (85.2% for doxorubicin and 87.8% for epirubicin). Acetone had little effect, whatever the type of molecule. Among products containing surfactants, DWL was found effective (91.5%), but its formulation

  8. Resource Control in Large-Scale Mobile-Agents Systems

    DTIC Science & Technology

    2005-07-01

    Narula ’02 (wireless networks, hand-held com- puters), Fred Reiss ’00, Dan Scholnick ’00, Matt Soldo ’99 (communication), Jeffrey Steeves ’99 (resource...George Cybenko, David Kotz, and Daniela Rus. Mobile agents: Motivations and state of the art. In Jeffrey Bradshaw, editor, Handbook of Agent Technology...Martin Hofmann, Jeffrey Bradshaw, Maggie Breedy, Renia Jeffers, and Niranjan Suri. Mobile-agent versus client/server performance: Scalability in an

  9. Design of a Multi-agent System for Personalized Service in the Smart Grid

    NASA Astrophysics Data System (ADS)

    Ko, Jinhee; Shin, In-Hye; Park, Gyung-Leen; Kwak, Ho-Yong; Ahn, Khi-Jung

    This paper designs a multi-agent system capable of providing personalized services in the smart grid, defining the relevant agent modules. The proposed system provides electricity consumers with personalized power purchase recommendation. Our framework consists of four agents and seven object categories. For the operation center which manages and controls the whole system, an adaptive agent, a coordination agent, and a filtering agent are defined, while a consumer agent is define for each home to collect the history of power consumption. Based on the analysis of the consumer, power market, residence, power consumption, appliance, family member, and electric vehicle objects, those agents autonomously cooperate to provide a personalized power service to each smart grid entity. In addition, adaptive learning capability further improves the recommendation quality.

  10. Periodic Solutions of Hamiltonian Systems: A Survey.

    DTIC Science & Technology

    1980-12-01

    auto - nomous Hamiltonian system has the form: (0.) aH 8Hp -S-(p,q) q ( where d denotes This system can be represented more concisely as (HS) z = ZHz(Z...oscillazioni periodiche d’une sistema dinamico, Atti. Accad. Naz. Lincei Rend. Cl. Sci. Fis. Mat. Natur., 19, (1934), 234-237. [15] Arnold, V. I

  11. A multi-agent approach to the design of an e-health system.

    PubMed

    Di Giacomo, Paola; Ricci, Fabrizio L

    2006-01-01

    E-medicine covers the whole range of medical process and service. Multi-agent approach is suitable for the development of e-medicine systems. In this paper, firstly the requirements of e-medicine are analyzed and taxonomy is proposed for e-medicine systems. Secondly multi-agent approach is introduced for developing e-medicine systems, and the design of agents and the design of multi-agent structure are presented for e-medicine systems. Finally a case study is presented on a telemedicine for diabetes to illustrate the development of e-medicine systems. Then, our future work is to implement the proposed system.

  12. Caveats for the New Localism in Further Education--Why the Use of Principal-Agent Solutions at the Local Level Will Not Work

    ERIC Educational Resources Information Center

    Boocock, Andrew

    2017-01-01

    The post-incorporation further education (FE) sector has experienced a number of quasi-markets over the past 23 years designed to incentivise college agents (managers and lecturers) to meet government objectives. To create such quasi-markets principal-agent (P-A) solutions have been introduced in the form of a series of funding incentives and…

  13. Tholins as Coloring Agents on Outer Solar System Bodies

    NASA Technical Reports Server (NTRS)

    Cruikshank, Dale P.; Imanaka, Hiroshi; DalleOre, Cristina M.

    2005-01-01

    The red colors of many solid bodies in outer Solar System may be caused by tholins, which are refractory organic complexes, incorporated in their surface materials. Tholins synthesized in the laboratory are shown to match the colors of these bodies when their optical properties are used in rigorous scattering models. We review recent successes in modeling the spectra of icy outer Solar System bodies with tholins as the coloring agents. New work on the systematic laboratory synthesis and analysis of tholins made by cold plasma discharge in mixtures of gaseous CH4/N2 shows that the composition of the tholin depends strongly on the pressure in the reaction chamber, and only weakly on the mixing fraction of CH4 relative to N2. In tholins made at high pressure (e.g., 23 hPa) the abundance of aliphatic hydrocarbons is greater and the abundance of aromatic hydrocarbons is less than in tholins made at low pressure (e.g., 0.13 hPa). Tholins made at low deposition pressures show a greater abundance of N-H bonds.

  14. Detailed investigation of the radical-induced destruction of chemical warfare agent simulants in aqueous solution.

    PubMed

    Abbott, Amberashley; Sierakowski, Tim; Kiddle, James J; Clark, Kristin K; Mezyk, Stephen P

    2010-06-10

    The persistence of delivered chemical warfare agents (CWAs) in a variety of environmental matrices is of serious concern to both the military and civilian populations. Ultimately understanding all of the degradation pathways of the various CWAs in different environmental matrices is essential for determining whether native processes would offer sufficient decontamination of a particular material or if active chemical decontamination is required. Whereas much work on base-promoted chemical degradation has been reported, additional remediation strategies such as the use of advanced oxidation or reduction process free radical treatments may also be a viable option. We have examined here the primary kinetics and reaction mechanisms for an extensive library of chemical warfare agent simulants with the oxidizing hydroxyl radical and reducing hydrated electrons in water. From these values, it is seen that the reductive destruction occurs primarily through a single mechanism, consisting of hydrated electron capture at the phosphorus group with subsequent elimination, whereas hydroxyl radical oxidation shows two separate reaction mechanisms, dependent on the aqueous pK(a) of the leaving group.

  15. A Method of Fault Detection in Power System by using Multi-agent Approach

    NASA Astrophysics Data System (ADS)

    Fukunaga, Shinnosuke; Nagata, Takeshi; Tani, Kazuhiro; Shimada, Ikuhiko

    In this paper, we propose a new decentralized multi-agent approach for detecting fault equipment in power system. The proposed method consists of several Substation agents (SSAGs), Distribution substations (DSAGs) and Line agents (LAGs). SSAG is installed each substation and controls its substation. DSAG is installed each distribution substation and receives instruction from SSAG or LAG. LAG is installed any substation and controls the transmission line. In order to demonstrate the capability of proposed multi-agent system, it has been applied to a model power system that has 7 substations and 8 distribution substations. The simulation results show that the proposed multi-agent approach is effective and promising.

  16. A multi-agent-based, semantic-driven system for decision support in epidemic management.

    PubMed

    Li, Sen; Mackaness, William A

    2015-09-01

    Issues in epidemiology are truly multidisciplinary, requiring knowledge from diverse disciplines such as sociology, medicine, biology, geography and information science. Such inherent complexity has led to a challenge in developing decision support systems for epidemic information management, especially when data are from heterogeneous origins. In order to achieve a solution, an integrative framework is proposed. The Semantic Web is introduced in the context of enriching meaningful and machine-readable descriptions of epidemiological data. Software agents are utilised to achieve automation in semantic discovery, composition of data and process services. The objective is to enhance the performance in information retrieval in a dynamic decision-making environment while concealing technical complexity from inexperienced users. We illustrate how a prototype system can be developed by considering an epidemiology management scenario in which spatio-temporal analysis is undertaken of a specified epidemic. © The Author(s) 2014.

  17. 29 CFR 1910.162 - Fixed extinguishing systems, gaseous agent.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... designed concentration of gaseous agents is maintained until the fire has been extinguished or is under... employee alarm capable of being perceived above ambient light or noise levels when agent design... ADMINISTRATION, DEPARTMENT OF LABOR OCCUPATIONAL SAFETY AND HEALTH STANDARDS Fire Protection Fixed Fire...

  18. 29 CFR 1910.162 - Fixed extinguishing systems, gaseous agent.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... designed concentration of gaseous agents is maintained until the fire has been extinguished or is under... employee alarm capable of being perceived above ambient light or noise levels when agent design... ADMINISTRATION, DEPARTMENT OF LABOR OCCUPATIONAL SAFETY AND HEALTH STANDARDS Fire Protection Fixed Fire...

  19. 29 CFR 1910.162 - Fixed extinguishing systems, gaseous agent.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... designed concentration of gaseous agents is maintained until the fire has been extinguished or is under... employee alarm capable of being perceived above ambient light or noise levels when agent design... ADMINISTRATION, DEPARTMENT OF LABOR OCCUPATIONAL SAFETY AND HEALTH STANDARDS Fire Protection Fixed Fire...

  20. 29 CFR 1910.162 - Fixed extinguishing systems, gaseous agent.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... designed concentration of gaseous agents is maintained until the fire has been extinguished or is under... employee alarm capable of being perceived above ambient light or noise levels when agent design... ADMINISTRATION, DEPARTMENT OF LABOR OCCUPATIONAL SAFETY AND HEALTH STANDARDS Fire Protection Fixed Fire...

  1. 29 CFR 1910.162 - Fixed extinguishing systems, gaseous agent.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... designed concentration of gaseous agents is maintained until the fire has been extinguished or is under... employee alarm capable of being perceived above ambient light or noise levels when agent design... ADMINISTRATION, DEPARTMENT OF LABOR OCCUPATIONAL SAFETY AND HEALTH STANDARDS Fire Protection Fixed Fire...

  2. Teamcore Project Control of Agent-Based Systems (COABS) Program

    DTIC Science & Technology

    2002-09-01

    Email Agents ___________________________________________________________________ 22 3.4.2 Palm Pilot Agents...12 Figure 7: PDA ( Palm VII) with GPS device for wireless, handheld communication between proxy and user. __ 14...while reducing the burden on humans. Tied to individual user workstations, fax machines, voice, mobile devices such as cell phones and palm pilots

  3. Avatars, Pedagogical Agents, and Virtual Environments: Social Learning Systems Online

    ERIC Educational Resources Information Center

    Ausburn, Lynna J.; Martens, Jon; Dotterer, Gary; Calhoun, Pat

    2009-01-01

    This paper presents a review of literature that introduces major concepts and issues in using avatars and pedagogical agents in first- and second-person virtual environments (VEs) for learning online. In these VEs, avatars and pedagogical agents represent self and other learners/participants or serve as personal learning "guides". The…

  4. An Agent-Based Cockpit Task Management System

    NASA Technical Reports Server (NTRS)

    Funk, Ken

    1997-01-01

    An agent-based program to facilitate Cockpit Task Management (CTM) in commercial transport aircraft is developed and evaluated. The agent-based program called the AgendaManager (AMgr) is described and evaluated in a part-task simulator study using airline pilots.

  5. Automated volumetric analysis for comparison of oral sulfate solution (SUPREP) with established cathartic agents at CT colonography

    PubMed Central

    Bannas, Peter; Bakke, Joshua; Patrick, James L.; Pickhardt, Perry J.

    2015-01-01

    Purpose To objectively compare residual colonic fluid volume and attenuation of oral sulfate solution (OSS) with four different established cathartic regimens using an automated volumetric software tool at CT colonography (CTC). Methods This HIPAA-compliant study had institutional review board approval. Volumetric analysis of residual contrast-tagged colonic fluid was performed on CTC studies in 263 adults (mean age, 60.1 years; 137M/126F) using an automated volumetric software tool. 23 patients receiving 177 ml OSS (SUPREP; single-bottle purgation) were compared with 60 patients each receiving 45 ml sodium phosphate (NaP), 90 ml NaP (2xNaP), 592 ml (two bottles) magnesium citrate (MgC), and 4000 ml polyethylene glycol (PEG). All patients received oral contrast cleansing after catharsis. Data were analyzed with unpaired t test with Welch correction and F test. Results The mean volume of residual colonic fluid was less with OSS (125±60 ml) than for established cathartic agents: 2xNaP (206±125 ml, (p<0.0001), MgC (184±125 ml, p<0.01), PEG (166±114 ml, p<0.05) and NaP (165±135 ml, p=0.067). Variance of volumes was also significantly lower for OSS (range, 28 – 251 ml) than for established agents (range, 4 – 853 ml) (all p<0.01). Mean fluid attenuation was higher with OSS (956±168 HU) than for established agents (all p<0.05): 2xNaP (455±191 HU), MgC (691±154 HU), NaP (779±127 HU), and PEG (843±193 HU). Conclusions Automated volumetry allows rapid objective assessment of bowel preparation quality at CTC. Purgation with the novel oral sulfate solution (SUPREP) consistently resulted in less residual colonic fluid and higher fluid attenuation compared with established cathartic regimens. PMID:24965898

  6. Pain and swelling after periapical surgery related to the hemostatic agent used: Anesthetic solution with vasoconstrictor or aluminum chloride

    PubMed Central

    Maestre-Ferrín, Laura; Peñarrocha-Oltra, David; Gay-Escoda, Cosme; von-Arx, Tomas; Peñarrocha-Diago, Miguel

    2012-01-01

    Objective: To assess pain and swelling in the first 7 days after periapical surgery and their relationship with the agent used for bleeding control. Study Design: A prospective study was conducted between October 2006 and March 2009. Patients subjected to root surgery, who completed the questionnaire and who consented to the postoperative instructions were included in the study. The subjects were divided into two groups according to the hemostatic agent used: A) gauze impregnated with anesthetic solution with vasoconstrictor; or B) aluminum chloride. The patients were administered a questionnaire, and were asked to record the severity of their pain and swelling on a plain horizontal visual analog scale (VAS). Data were recorded by the patients on the first 7 postoperative days. In addition, the patients were asked to record analgesic consumption. Results: A total of 76 questionnaires (34 in group A and 42 in group B) were taken to be correctly completed. Pain was reported to be most intense two hours after surgery. At this point 52.6% of the patients had no pain. Seventy-five percent of the patients consumed analgesics in the first 24 hours. There were no significant differences between the two groups in terms of the intensity of pain or in the consumption of analgesics. Swelling reached its maximum peak on the second day; at this point, 60.6% of the patients suffered mild or moderate swelling. The Expasyl™ group showed significantly greater swelling than the gauzes group. Conclusion: The type of hemostatic agent used did not influence either the degree of pain or the need for analgesia among the patients in this study. However, the patients belonging to the Expasyl™ group suffered greater swelling than the patients treated with gauzes impregnated with anesthetic solution with vasoconstrictor. Key words:Hemostasis, periradicular surgery, aluminum chloride, pain, swelling. PMID:22322510

  7. Systems biology solutions for biochemical production challenges.

    PubMed

    Hansen, Anne Sofie Lærke; Lennen, Rebecca M; Sonnenschein, Nikolaus; Herrgård, Markus J

    2017-06-01

    There is an urgent need to significantly accelerate the development of microbial cell factories to produce fuels and chemicals from renewable feedstocks in order to facilitate the transition to a biobased society. Methods commonly used within the field of systems biology including omics characterization, genome-scale metabolic modeling, and adaptive laboratory evolution can be readily deployed in metabolic engineering projects. However, high performance strains usually carry tens of genetic modifications and need to operate in challenging environmental conditions. This additional complexity compared to basic science research requires pushing systems biology strategies to their limits and often spurs innovative developments that benefit fields outside metabolic engineering. Here we survey recent advanced applications of systems biology methods in engineering microbial production strains for biofuels and -chemicals. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  8. Highly integrated system solutions for air conditioning.

    PubMed

    Bartz, Horst

    2002-08-01

    Starting with the air handling unit, new features concerning energy efficient air treatment in combination with optimisation of required space were presented. Strategic concepts for the supply of one or more operating suites with a modular based air handling system were discussed. The operating theatre ceiling itself, as a major part of the whole integrated system, is no longer a simple air outlet: additional functions have been added in so-called media-bridges, so that it has changed towards a medical apparatus serving as a daily tool for the physicians and the operating staff. Last and not least, the servicing of the whole system has become an integral part of the facility management with remote access to the main functions and controls. The results are understood to be the basis for a discussion with specialists from medical and hygienic disciplines as well as with technically orientated people representing the hospital and building-engineering.

  9. A criticality-based framework for task composition in multi-agent bioinformatics integration systems.

    PubMed

    Karasavvas, Konstantinos A; Baldock, Richard; Burger, Albert

    2005-07-15

    During task composition, such as can be found in distributed query processing, workflow systems and AI planning, decisions have to be made by the system and possibly by users with respect to how a given problem should be solved. Although there is often more than one correct way of solving a given problem, these multiple solutions do not necessarily lead to the same result. Some researchers are addressing this problem by providing data provenance information. Others use expert advice encoded in a supporting knowledge-base. In this paper, we propose an approach that assesses the importance of such decisions with respect to the overall result. We present a way of measuring decision criticality and describe its potential use. A multi-agent bioinformatics integration system is used as the basis of a framework that facilitates such functionality. We propose an agent architecture, and a concrete bioinformatics example (prototype) is used to show how certain decisions may not be critical in the context of more complex tasks.

  10. Analysis of flash echo from contrast agent for designing optimal ultrasound diagnostic systems.

    PubMed

    Kamiyama, N; Moriyasu, F; Mine, Y; Goto, Y

    1999-03-01

    Microbubble-based contrast agents can enhance echoes in areas of low blood flow, but the bubbles are extremely sensitive and collapse easily when exposed to ultrasound (US) irradiation. An experimental study of bubble collapse was carried out to design new functions for US diagnostic systems to detect echoes from microbubbles more efficiently. For contrast agent (Levovist) solution, a high-intensity, but momentary, echo (flash echo), was observed in the first frame image after a several-second suspension of transmission, but was not seen in the second frame image. These "flash echo" signals were analyzed and categorized based on microscopic observation, and the results showed that the longevity of the microbubbles was reduced by conditions such as B-mode imaging. Next, a numerical simulation of the bubbles in liquid was performed under the same conditions as in the in vitro experiment. The results showed that even bubbles less than 1 microm in diameter expand and collapse within one pulse drive, which would generate flash echoes. The flash echo imaging system described here permits flexible intermittent scanning with variable intervals, with a variable number of frames at the trigger, and with simultaneous monitoring at low power output. Animal experiments were also conducted to evaluate the system. As the interval between frames was increased, the flash echoes gradually increased, and perfusion in the parenchyma was clearly observed with an interval of 4 s.

  11. Epidemiologic studies of environmental agents and systemic autoimmune diseases.

    PubMed Central

    Mayes, M D

    1999-01-01

    Systemic lupus erythematosus and systemic scleroderma are autoimmune diseases thought to have an exogenous trigger. This review summarizes relevant case-control and cohort studies that investigated exogenous sex hormones, silica, silicone, solvents, pesticides, mercuric chloride, and hair dyes as putative risk factors for the development of these diseases. These studies indicate that estrogen replacement therapy in postmenopausal women increases the risk of developing lupus, scleroderma, and Raynaud disease, although the increase in risk is relatively modest. Oral contraceptives may also play a role in disease susceptibility in lupus but not apparently in scleroderma. Environmental endocrine modulators, in the form of pesticides, may represent another opportunity for estrogenlike effects to occur, but there is scant evidence that these agents play a role in human systemic autoimmune disease. Although exposure to silica dust increases the risk of scleroderma in men occupied in the industry, this does not explain most male scleroderma cases. When this exposure was investigated among women, no significant risk was found. Additionally, silicone in implanted devices as well as occupational exposure to silicone-containing compounds did not pose an increased risk among women for scleroderma. The role of solvent exposure has been investigated as a risk factor for scleroderma with mixed findings. One study suggested a potential role in male patients or in those individuals with Scl-70 antibody positivity either male or female. Two other studies were unable to corroborate this finding. Mercuric chloride causes antifibrillarin antibodies and immune complex glomerulonephritis in susceptible mouse strains. Antifibrillarin antibodies, but not glomerulonephritis, occur in a subset of scleroderma patients and preliminary evidence suggests that mercury levels may be higher in this group of individuals. Hair products have been studied as possibly raising the risk of developing lupus

  12. A dilution-filtration system for removing cryoprotective agents.

    PubMed

    Zhou, Xiaoming; Liu, Zhong; Shu, Zhiquan; Ding, Weiping; Du, Pingan; Chung, JaeHyun; Liu, Carolyn; Heimfeld, Shelly; Gao, Dayong

    2011-02-01

    In most cryopreservation applications, the final concentrations of cryoprotective agents (CPAs) must be reduced to biocompatible levels. However, traditional methods for removing CPAs usually have disadvantages of operation complexity, time consumption, and ease of contamination, especially for the applications involving large volumes of cell suspensions. A dilution-filtration system, which involves pure ultrafiltration for separation, was developed for continuous, automatic, and closed process of removing CPAs. To predict the optimal protocols under given experimental conditions, a theoretical model was established first. Cell-free experiments were then conducted to investigate the variation in CPA concentration during the process, and the experimental data were compared with the theoretical values for the validation of the model. Finally, ten units (212.9 ml/unit±9.5 ml/unit) of thawed human red blood cells (cryopreserved with 40% (w/v) glycerol) were deglycerolized using the theoretically optimal operation protocols to further validate the effectiveness and advantage of the system. In the cell-free experiments, glycerol was continuously removed and the concentration variations fitted the simulated results quite well. In the in-vitro experiments, glycerol concentration in RBC suspension was reduced to 5.57 g/l±2.81 g/l within an hour, and the cell count recovery rate was 91.19%±3.57%, (n=10), which proves that the system is not only safe for removing CPAs, but also particularly efficient for processing large-scale samples. However, the operation parameters must be carefully controlled and the optimal protocols should be specialized and various from case to case. The presented theoretical model provides an effective approach to find out the optimal operation protocols under given experimental conditions and constrains.

  13. Eight challenges in modelling disease ecology in multi-host, multi-agent systems

    PubMed Central

    Buhnerkempe, Michael G.; Roberts, Mick G.; Dobson, Andrew P.; Heesterbeek, Hans; Hudson, Peter J.; Lloyd-Smith, James O.

    2015-01-01

    Many disease systems exhibit complexities not captured by current theoretical and empirical work. In particular, systems with multiple host species and multiple infectious agents (i.e., multi-host, multi-agent systems) require novel methods to extend the wealth of knowledge acquired studying primarily single-host, single-agent systems. We outline eight challenges in multi-host, multi-agent systems that could substantively increase our knowledge of the drivers and broader ecosystem effects of infectious disease dynamics. PMID:25843378

  14. More Student Success: A Systemic Solution

    ERIC Educational Resources Information Center

    State Higher Education Executive Officers, 2007

    2007-01-01

    This book tells how to build a system leading to more student success beginning in elementary school and continuing through high school and postsecondary education. It identifies the key elements, describes effective practices, and shows how they come together to help students and educators succeed. "More Student Success" is an updated and…

  15. Multiaccommodative stimuli in VR systems: problems & solutions.

    PubMed

    Marran, L; Schor, C

    1997-09-01

    Virtual reality environments can introduce multiple and sometimes conflicting accommodative stimuli. For instance, with the high-powered lenses commonly used in head-mounted displays, small discrepancies in screen lens placement, caused by manufacturer error or user adjustment focus error, can change the focal depths of the image by a couple of diopters. This can introduce a binocular accommodative stimulus or, if the displacement between the two screens is unequal, an unequal (anisometropic) accommodative stimulus for the two eyes. Systems that allow simultaneous viewing of virtual and real images can also introduce a conflict in accommodative stimuli: When real and virtual images are at different focal planes, both cannot be in focus at the same time, though they may appear to be in similar locations in space. In this paper four unique designs are described that minimize the range of accommodative stimuli and maximize the visual system's ability to cope efficiently with the focus conflicts that remain: pinhole optics, monocular lens addition combined with aniso-accommodation, chromatic bifocal, and bifocal lens system. The advantages and disadvantages of each design are described and recommendation for design choice is given after consideration of the end use of the virtual reality system (e.g., low or high end, entertainment, technical, or medical use). The appropriate design modifications should allow greater user comfort and better performance.

  16. Crystallization in solid solution-aqueous solution systems: Thermodynamic and kinetic approaches

    SciTech Connect

    Shtukenberg, A. G. Punin, Yu. O.; Azimov, P. Ya.

    2010-03-15

    A new phenomenological approach is proposed to describe the crystallization kinetics in solid solution-aqueous solution binary systems. The phase diagrams, equilibria, and quasie-quilibria are considered within this approach. The crystallization kinetics near the true equilibrium and the crystallization features at large deviations from equilibrium are discussed on this basis. Special attention is paid to possible interactions in a solution with a seed crystal placed in it. In particular, the interactions leading to the seed's crystal growth or dissolution and to a possible exchange or metasomatic reactions are considered. In addition, the effect of the generated mismatch stress on the crystal growth rate and composition is analyzed.

  17. Analytical solutions for systems of partial differential-algebraic equations.

    PubMed

    Benhammouda, Brahim; Vazquez-Leal, Hector

    2014-01-01

    This work presents the application of the power series method (PSM) to find solutions of partial differential-algebraic equations (PDAEs). Two systems of index-one and index-three are solved to show that PSM can provide analytical solutions of PDAEs in convergent series form. What is more, we present the post-treatment of the power series solutions with the Laplace-Padé (LP) resummation method as a useful strategy to find exact solutions. The main advantage of the proposed methodology is that the procedure is based on a few straightforward steps and it does not generate secular terms or depends of a perturbation parameter.

  18. Boundedness of solutions for reversible system via Moser's twist theorem

    NASA Astrophysics Data System (ADS)

    Piao, Daxiong; Li, Wenling

    2008-05-01

    In this paper we consider the problem of the boundedness of all solutions for the reversible system It is shown that all the solutions are bounded provided that the ai(t) (0[less-than-or-equals, slant]i[less-than-or-equals, slant][(n-1)/2]) are of bounded variation in [0,1] and the derivatives of bj(t) and ai(t) are Lipschitzian. It is also shown that there exist ai's being discontinuous everywhere such that all solutions of the equation are bounded. This implies that the continuity of ai's is not necessary for the boundedness of solutions of the equation.

  19. Graph-theoretic characterisations of structural controllability for multi-agent system with switching topology

    NASA Astrophysics Data System (ADS)

    Liu, Xiaomeng; Lin, Hai; Chen, Ben M.

    2013-02-01

    This article considers the controllability problem for multi-agent systems. In particular, the structural controllability of multi-agent systems under switching topologies is investigated. The structural controllability of multi-agent systems is a generalisation of the traditional controllability concept for dynamical systems, and purely based on the communication topologies among agents. The main contributions of this article are graph-theoretic characterisations of the structural controllability for multi-agent systems. It turns out that the multi-agent system with switching topology is structurally controllable if and only if the union graph 𝒢 of the underlying communication topologies is connected (single leader) or leader-follower connected (multi-leader). Finally, this article concludes with several illustrative examples and discussions of the results and future work.

  20. Impulsive observer-based consensus control for multi-agent systems with time delay

    NASA Astrophysics Data System (ADS)

    Qin, Wen; Liu, Zhongxin; Chen, Zengqiang

    2015-09-01

    The paper deals with the distributed consensus problem of a class of general linear multi-agent systems with time delay. Assuming that the state of the multi-agent system cannot be measured and the output of the multi-agent system is measured discontinuously, a novel impulsive observer is constructed. Based on the impulsive observer, a distributed consensus protocol is proposed for the multi-agent system with a directed communication topology. In view of the hybrid characteristic of the multi-agent system with the impulsive observer, a novel type of piecewise Lyapunov functional which can overcome the jump phenomena at impulsive times is introduced. Based on this, some sufficient conditions in terms of linear matrix inequalities are presented such that the consensus of the multi-agent system can be achieved with an exponential convergence rate. A numerical example under two cases is given to show the effectiveness of the theoretical results.

  1. Numerical simulation study of silica and calcite dissolution around a geothermal well by injecting high pH solutions with chelating agent.

    SciTech Connect

    Xu, Tianfu; Rose, Peter; Fayer, Scott; Pruess, Karsten

    2009-02-01

    Dissolution of silica, silicate, and calcite minerals in the presence of a chelating agent (NTA) at a high pH has been successfully performed in the laboratory using a high-temperature flow reactor. The mineral dissolution and porosity enhancement in the laboratory experiment has been reproduced by reactive transport simulation using TOUGHREACT. The chemical stimulation method has been applied by numerical modeling to a field geothermal injection well system, to investigate its effectiveness. Parameters from the quartz monzodiorite unit at the Enhanced Geothermal System (EGS) site at Desert Peak (Nevada) were used. Results indicate that the injection of a high pH chelating solution results in dissolution of both calcite and plagioclase minerals, and avoids precipitation of calcite at high temperature conditions. Consequently reservoir porosity and permeability can be enhanced especially near the injection well.

  2. Requirements and Solutions for Personalized Health Systems.

    PubMed

    Blobel, Bernd; Ruotsalainen, Pekka; Lopez, Diego M; Oemig, Frank

    2017-01-01

    Organizational, methodological and technological paradigm changes enable a precise, personalized, predictive, preventive and participative approach to health and social services supported by multiple actors from different domains at diverse level of knowledge and skills. Interoperability has to advance beyond Information and Communication Technologies (ICT) concerns, including the real world business domains and their processes, but also the individual context of all actors involved. The paper introduces and compares personalized health definitions, summarizes requirements and principles for pHealth systems, and considers intelligent interoperability. It addresses knowledge representation and harmonization, decision intelligence, and usability as crucial issues in pHealth. On this basis, a system-theoretical, ontology-based, policy-driven reference architecture model for open and intelligent pHealth ecosystems and its transformation into an appropriate ICT design and implementation is proposed.

  3. Finite-element solutions for geothermal systems

    NASA Technical Reports Server (NTRS)

    Chen, J. C.; Conel, J. E.

    1977-01-01

    Vector potential and scalar potential are used to formulate the governing equations for a single-component and single-phase geothermal system. By assuming an initial temperature field, the fluid velocity can be determined which, in turn, is used to calculate the convective heat transfer. The energy equation is then solved by considering convected heat as a distributed source. Using the resulting temperature to compute new source terms, the final results are obtained by iterations of the procedure. Finite-element methods are proposed for modeling of realistic geothermal systems; the advantages of such methods are discussed. The developed methodology is then applied to a sample problem. Favorable agreement is obtained by comparisons with a previous study.

  4. Finite-element solutions for geothermal systems

    NASA Technical Reports Server (NTRS)

    Chen, J. C.; Conel, J. E.

    1977-01-01

    Vector potential and scalar potential are used to formulate the governing equations for a single-component and single-phase geothermal system. By assuming an initial temperature field, the fluid velocity can be determined which, in turn, is used to calculate the convective heat transfer. The energy equation is then solved by considering convected heat as a distributed source. Using the resulting temperature to compute new source terms, the final results are obtained by iterations of the procedure. Finite-element methods are proposed for modeling of realistic geothermal systems; the advantages of such methods are discussed. The developed methodology is then applied to a sample problem. Favorable agreement is obtained by comparisons with a previous study.

  5. Iterative solution of high order compact systems

    SciTech Connect

    Spotz, W.F.; Carey, G.F.

    1996-12-31

    We have recently developed a class of finite difference methods which provide higher accuracy and greater stability than standard central or upwind difference methods, but still reside on a compact patch of grid cells. In the present study we investigate the performance of several gradient-type iterative methods for solving the associated sparse systems. Both serial and parallel performance studies have been made. Representative examples are taken from elliptic PDE`s for diffusion, convection-diffusion, and viscous flow applications.

  6. The Use of Multi-Agent Systems to Build Intelligent Tutoring Systems

    NASA Astrophysics Data System (ADS)

    Vicari, Rosa M.; Giraffa, Lucia M. M.

    2002-09-01

    The paper presents our experiments and results in order to explore the possibilities of building ITS (Intelligent Tutoring Systems) using a MAS (Multi-Agent Systems) approach. This approach helps us to study the intrinsic complexity of educational environments that consider more than one student working in a co-operative way (designed to be used on the WEB or without it). We present results that arose from previous work on the use of mental and affective states to build student and tutor models. This paper organises the results our group achieved, and tries to present and discuss the problems of having a more complex situation where more than two agents (tutor and student) appear. Overall, the goal of our research group is to have a social environment where several tutors and students interact in teaching and learning situations. We pursue a social model that would represent the society of pedagogical agents existing in an interactive ITS.

  7. The Triple Value Model: A Systems Approach to Sustainable Solutions

    EPA Science Inventory

    The unintended environmental impacts of economic development threaten the continued availability of ecosystem services that are critical to human well being. An integrated systems approach is needed to characterize sustainability problems and evaluate potential solutions. The T...

  8. The Triple Value Model: A Systems Approach to Sustainable Solutions

    EPA Science Inventory

    The unintended environmental impacts of economic development threaten the continued availability of ecosystem services that are critical to human well being. An integrated systems approach is needed to characterize sustainability problems and evaluate potential solutions. The T...

  9. Multi-Agent System for Mission and Situational Awareness Management (MASAM) for Airborne Platforms

    DTIC Science & Technology

    2003-01-01

    UNCLASSIFIED MULTI - AGENT SYSTEM FOR MISSION AND SITUATIONAL AWARENESS MANAGEMENT (MASAM) FOR AIRBORNE PLATFORMS (U) John C. Sciortino, Jr...TYPE 3. DATES COVERED 00-00-2003 to 00-00-2003 4. TITLE AND SUBTITLE Multi - Agent System for Mission and Situational Awareness Management (MASAM...Parameters Platform Figure 3: (U) Multi - Agent System for Mission and Situational Awareness Management (Left Panel). Use of CoABS Grid (Right Panel

  10. Model of interaction in Smart Grid on the basis of multi-agent system

    NASA Astrophysics Data System (ADS)

    Engel, E. A.; Kovalev, I. V.; Engel, N. E.

    2016-11-01

    This paper presents model of interaction in Smart Grid on the basis of multi-agent system. The use of travelling waves in the multi-agent system describes the behavior of the Smart Grid from the local point, which is being the complement of the conventional approach. The simulation results show that the absorption of the wave in the distributed multi-agent systems is effectively simulated the interaction in Smart Grid.

  11. Addressing Production System Failures Using Multi-agent Control

    NASA Astrophysics Data System (ADS)

    Gautam, Rajesh; Miyashita, Kazuo

    Output in high-volume production facilities is limited by bottleneck machines. We propose a control mechanism by modeling workstations as agents that pull jobs from other agents based on their current WIP level and requirements. During failures, when flows of some jobs are disrupted, the agents pull alternative jobs to maintain utilization of their capacity at a high level. In this paper, we empirically demonstrate that the proposed mechanism can react to failures more appropriately than other control mechanisms using a benchmark problem of a semiconductor manufacturing process.

  12. Biogeochemistry of fluoride in a plant-solution system

    NASA Technical Reports Server (NTRS)

    Mackowiak, C. L.; Grossl, P. R.; Bugbee, B. G.

    2003-01-01

    Fluoride (F-) pollutants can harm plants and the animals feeding on them. However, it is largely unknown how complexing and chelating agents affect F bioavailability. Two studies were conducted that measured F- bioavailability and uptake by rice (Oryza sativa L.). In the first study, rice was grown in solution culture (pH 5.0) with 0, 2, or 4 mM F- as KF to compare the interaction of F- with humic acid (HA) and with a conventional chelating agent, N-hydroxyethylenthylenediaminetriacetic acid (HEDTA). In the second study, F was supplied at 0, 0.5, 1.0, and 2.0 mM KF with an additional 2 mM F- treatment containing solution Ca at 2x (2 mM Ca) the level used in the first study, to test the effect added Ca had on F- availability and uptake. Total biomass was greatest with HEDTA and F- < 1 mM. Leaf and stem F concentrations increased exponentially as solution F- increased linearly, with nearly no F partitioning into the seed. Results suggest that F was taken up as HF0 while F- uptake was likely restricted. Additionally, F- competed with HA for Ca, thus preventing the formation of Ca-HA flocculents. The addition of soluble Ca resulted in the precipitation of CaF2 solids on the root surface, as determined by tissue analysis and energy dispersive X-ray spectroscopy.

  13. Biogeochemistry of fluoride in a plant-solution system

    NASA Technical Reports Server (NTRS)

    Mackowiak, C. L.; Grossl, P. R.; Bugbee, B. G.

    2003-01-01

    Fluoride (F-) pollutants can harm plants and the animals feeding on them. However, it is largely unknown how complexing and chelating agents affect F bioavailability. Two studies were conducted that measured F- bioavailability and uptake by rice (Oryza sativa L.). In the first study, rice was grown in solution culture (pH 5.0) with 0, 2, or 4 mM F- as KF to compare the interaction of F- with humic acid (HA) and with a conventional chelating agent, N-hydroxyethylenthylenediaminetriacetic acid (HEDTA). In the second study, F was supplied at 0, 0.5, 1.0, and 2.0 mM KF with an additional 2 mM F- treatment containing solution Ca at 2x (2 mM Ca) the level used in the first study, to test the effect added Ca had on F- availability and uptake. Total biomass was greatest with HEDTA and F- < 1 mM. Leaf and stem F concentrations increased exponentially as solution F- increased linearly, with nearly no F partitioning into the seed. Results suggest that F was taken up as HF0 while F- uptake was likely restricted. Additionally, F- competed with HA for Ca, thus preventing the formation of Ca-HA flocculents. The addition of soluble Ca resulted in the precipitation of CaF2 solids on the root surface, as determined by tissue analysis and energy dispersive X-ray spectroscopy.

  14. Asymptotic Growth of Solutions of Neutral Type Systems

    SciTech Connect

    Sklyar, G. M. Polak, P.

    2013-06-15

    We consider a differential system of neutral type with distributed delay. We obtain a precise norm estimation of semigroup generated by the operator corresponding to the system in question. Our result is based on a spectral analysis of the operator and some uniform estimation of norms of the exponentials of matrices. We also discuss the stability properties of corresponding solutions and the existence of the fastest growing solution.

  15. The Evolution of Cooperation in Managed Groundwater Systems: An Agent-Based Modelling Approach

    NASA Astrophysics Data System (ADS)

    Castilla Rho, J. C.; Mariethoz, G.; Rojas, R. F.; Andersen, M. S.; Kelly, B. F.; Holley, C.

    2014-12-01

    Human interactions with groundwater systems often exhibit complex features that hinder the sustainable management of the resource. This leads to costly and persistent conflicts over groundwater at the catchment scale. One possible way to address these conflicts is by gaining a better understanding of how social and groundwater dynamics coevolve using agent-based models (ABM). Such models allow exploring 'bottom-up' solutions (i.e., self-organised governance systems), where the behaviour of individual agents (e.g., farmers) results in the emergence of mutual cooperation among groundwater users. There is significant empirical evidence indicating that this kind of 'bottom-up' approach may lead to more enduring and sustainable outcomes, compared to conventional 'top-down' strategies such as centralized control and water right schemes (Ostrom 1990). New modelling tools are needed to study these concepts systematically and efficiently. Our model uses a conceptual framework to study cooperation and the emergence of social norms as initially proposed by Axelrod (1986), which we adapted to groundwater management. We developed an ABM that integrates social mechanisms and the physics of subsurface flow. The model explicitly represents feedback between groundwater conditions and social dynamics, capturing the spatial structure of these interactions and the potential effects on cooperation levels in an agricultural setting. Using this model, we investigate a series of mechanisms that may trigger norms supporting cooperative strategies, which can be sustained and become stable over time. For example, farmers in a self-monitoring community can be more efficient at achieving the objective of sustainable groundwater use than government-imposed regulation. Our coupled model thus offers a platform for testing new schemes promoting cooperation and improved resource use, which can be used as a basis for policy design. Importantly, we hope to raise awareness of agent-based modelling as

  16. Spectral and fluorescence imaging of immune system and tissue response to an immunogenic agent

    NASA Astrophysics Data System (ADS)

    Choe, Se-woon; Acharya, Abhinav; Keselowsky, Benjamin G.; Sorg, Brian S.

    2009-05-01

    Imaging of immune system and tissue response to immunogenic agents can be important to the development of new biomaterials. Additionally, quantitative functional imaging can be useful for testing and evaluation of methods to alter or control the immune system response to implanted materials. In this preliminary study, we employ spectral imaging and fluorescence imaging to measure immune system and tissue response to implanted immunogenic agents. Poly (D,L lactide-co-glycolide) (PLGA) with a 50:50 composition was used to create immunogenic microparticles (MPs). Lipopolysaccharide (LPS) encapsulated in the MPs was used to provoke a tissue immune response in mice and encapsulated fluorescein isothiocyanate (FITC) was used to fluorescently label the MPs for imaging. Control MPs did not contain LPS. The MPs were delivered at 50 particles/μL in a total volume of 20μL by subcutaneous injection in the skin of a nude mouse in a dorsal skin-fold window chamber preparation. Cultured immune cells from a mouse leukemic monocyte macrophage cell line were exogenously labeled with the fluorescent dye DiD in solution at a concentration of 8000cells/μL. Immediately after window chamber surgery and implantation of the MPs, 100μL of the fluorescent macrophage solution was administered via the tail vein. Fluorescence imaging was used to track MPs and macrophages while spectral imaging was used for imaging and measurement of hemoglobin saturation in the tissue microvasculature. Imaging was performed periodically over about three days. The spectral and fluorescence imaging combination enabled detailed observations of the macrophage response and functional effects on the tissue.

  17. Solvent recovery system provides timely compliance solution

    SciTech Connect

    1996-11-01

    Hoechst Celanese Corp. (Coventry, Rhode Island) faced the challenge of meeting an Environmental Protection Agency (EPA) deadline for solvent recovery within one year. The company also had to ensure that a new solvent recovery system would satisfy Rhode Island state requirements. An initial search for the required technology was fruitless. Finally, MG Industries (Saint Charles, Missouri), an industrial gas supplier, was chosen for the job. Using CRYOSOLV, as the waste stream cools in the cryogenic condenser (heat exchanger), the solvents condense at temperatures below the dewpoint. The recovered solvent can be recycled into the process, while clean gas is vented to the atmosphere.

  18. Intermittent observer-based consensus control for multi-agent systems with switching topologies

    NASA Astrophysics Data System (ADS)

    Xu, Xiaole; Gao, Lixin

    2016-06-01

    In this paper, we focus on the consensus problem for leaderless and leader-followers multi-agent systems with periodically intermittent control. The dynamics of each agent in the system is a linear system, and the interconnection topology among the agents is assumed to be switching. We assume that each agent can only share the outputs with its neighbours. Therefore, a class of distributed intermittent observer-based consensus protocols are proposed for each agent. First, in order to solve this problem, a parameter-dependent common Lyapunov function is constructed. Using this function, we prove that all agents can access a prescribed value, under the designed intermittent controller and observer, if there are suitable conditions on communication. Second, based on the investigation of the leader-following consensus problem, we design a new distributed intermittent observer-based protocol for each following agent. Finally, we provide an illustrative example to verify the effectiveness of the proposed approach.

  19. Shear bond strength of the Tenure Solution dentin bonding system.

    PubMed

    Barkmeier, W W; Cooley, R L

    1989-10-01

    A liquid solution of an oxalate bonding system containing NTG-GMA and PMDM has become commercially available. The bond strength of this oxalate adhesive (Tenure Solution) to dentin was determined by bonding composite resin cylinders to extracted teeth. The bond strengths obtained in this study are compared to the bond strengths obtained in earlier studies with the first and second generation oxalate adhesives whose components were supplied as powders and required mixing. The oxalate solutions developed significantly higher bond strengths than the original powder type systems.

  20. Parallel solution of closely coupled systems

    NASA Technical Reports Server (NTRS)

    Utku, S.; Salama, M.

    1986-01-01

    The odd-even permutation and associated unitary transformations for reordering the matrix coefficient A are employed as means of breaking the strong seriality which is characteristic of closely coupled systems. The nested dissection technique is also reviewed, and the equivalence between reordering A and dissecting its network is established. The effect of transforming A with odd-even permutation on its topology and the topology of its Cholesky factors is discussed. This leads to the construction of directed graphs showing the computational steps required for factoring A, their precedence relationships and their sequential and concurrent assignment to the available processors. Expressions for the speed-up and efficiency of using N processors in parallel relative to the sequential use of a single processor are derived from the directed graph. Similar expressions are also derived when the number of available processors is fewer than required.

  1. Modeling Complex Chemical Systems: Problems and Solutions

    NASA Astrophysics Data System (ADS)

    van Dijk, Jan

    2016-09-01

    Non-equilibrium plasmas in complex gas mixtures are at the heart of numerous contemporary technologies. They typically contain dozens to hundreds of species, involved in hundreds to thousands of reactions. Chemists and physicists have always been interested in what are now called chemical reduction techniques (CRT's). The idea of such CRT's is that they reduce the number of species that need to be considered explicitly without compromising the validity of the model. This is usually achieved on the basis of an analysis of the reaction time scales of the system under study, which identifies species that are in partial equilibrium after a given time span. The first such CRT that has been widely used in plasma physics was developed in the 1960's and resulted in the concept of effective ionization and recombination rates. It was later generalized to systems in which multiple levels are effected by transport. In recent years there has been a renewed interest in tools for chemical reduction and reaction pathway analysis. An example of the latter is the PumpKin tool. Another trend is that techniques that have previously been developed in other fields of science are adapted as to be able to handle the plasma state of matter. Examples are the Intrinsic Low Dimension Manifold (ILDM) method and its derivatives, which originate from combustion engineering, and the general-purpose Principle Component Analysis (PCA) technique. In this contribution we will provide an overview of the most common reduction techniques, then critically assess the pros and cons of the methods that have gained most popularity in recent years. Examples will be provided for plasmas in argon and carbon dioxide.

  2. [The CORBA solution of medical imaging and communication system].

    PubMed

    Wang, Yong; Lü, Yangsheng; Yu, Hui

    2005-02-01

    Due to the difficulty of communication and information share between Medical information systems, the Object Management Group issued the software specification of CORBAMed, defining the interfaces of services, and specifying the software architecture of Medical Information System. This paper attempts to use CORBA in Picture Archiving and Communication System (PACS), provides a system model of CORBA solution of PACS, and analyzes the view layers structure of system, finally we discuss the related services of CORBAMed.

  3. Numerical solution of multiscale electromagnetic systems

    NASA Astrophysics Data System (ADS)

    Tobon Llano, Luis Eduardo

    The Discontinuous Galerkin time domain (DGTD) method is promising in modeling of realistic multiscale electromagnetic systems. This method defines the basic concept for implementing the communication between multiple domains with different scales. Constructing a DGTD system consists of several careful choices: (a) governing equations; (b) element shape and corresponding basis functions for the spatial discretization of each subdomain; (c) numerical fluxes onto interfaces to bond all subdomains together; and (d) time stepping scheme based on properties of a discretized system. This work present the advances in each one of these steps. First, a unified framework based on the theory of differential forms and the finite element method is used to analyze the discretization of the Maxwell's equations. Based on this study, field intensities (E and H) are associated to 1-forms and curl-conforming basis functions; flux densities (D and B) are associated to 2-forms and divergence-conforming basis functions; and the constitutive relations are defined by Hodge operators. A different approach is the study of numerical dispersion. Semidiscrete analysis is the traditional method, but for high order elements modal analysis is prefered. From these analyses, we conclude that a correct discretization of fields belonging to different p-form (e.g., E and B ) uses basis functions with same order of interpolation; however, different order of interpolation must be used if two fields belong to the same p-form (e.g., E and H). An alternative method to evaluate numerical dispersion based on evaluation of dispersive Hodge operators is also presented. Both dispersion analyses are equivalent and reveal same fundamental results. Eigenvalues, eigenvector and transient results are studied to verify accuracy and computational costs of different schemes. Two different approaches are used for implementing the DG Method. The first is based on E and H fields, which use curl-conforming basis functions

  4. Parallel preconditioning for the solution of nonsymmetric banded linear systems

    SciTech Connect

    Amodio, P.; Mazzia, F.

    1994-12-31

    Many computational techniques require the solution of banded linear systems. Common examples derive from the solution of partial differential equations and of boundary value problems. In particular the authors are interested in the parallel solution of block Hessemberg linear systems Gx = f, arising from the solution of ordinary differential equations by means of boundary value methods (BVMs), even if the considered preconditioning may be applied to any block banded linear system. BVMs have been extensively investigated in the last few years and their stability properties give promising results. A new class of BVMs called Reverse Adams, which are BV-A-stable for orders up to 6, and BV-A{sub 0}-stable for orders up to 9, have been studied.

  5. On the use of multi-agent systems for the monitoring of industrial systems

    NASA Astrophysics Data System (ADS)

    Rezki, Nafissa; Kazar, Okba; Mouss, Leila Hayet; Kahloul, Laid; Rezki, Djamil

    2016-12-01

    The objective of the current paper is to present an intelligent system for complex process monitoring, based on artificial intelligence technologies. This system aims to realize with success all the complex process monitoring tasks that are: detection, diagnosis, identification and reconfiguration. For this purpose, the development of a multi-agent system that combines multiple intelligences such as: multivariate control charts, neural networks, Bayesian networks and expert systems has became a necessity. The proposed system is evaluated in the monitoring of the complex process Tennessee Eastman process.

  6. Temperature Profile of the Solution Vessel of an Accelerator-Driven Subcritical Fissile Solution System

    SciTech Connect

    Klein, Steven Karl; Determan, John C.

    2015-09-14

    Dynamic System Simulation (DSS) models of fissile solution systems have been developed and verified against a variety of historical configurations. DSS techniques have been applied specifically to subcritical accelerator-driven systems using fissile solution fuels of uranium. Initial DSS models were developed in DESIRE, a specialized simulation scripting language. In order to tailor the DSS models to specifically meet needs of system designers they were converted to a Visual Studio implementation, and one of these subsequently to National Instrument’s LabVIEW for human factors engineering and operator training. Specific operational characteristics of subcritical accelerator-driven systems have been examined using a DSS model tailored to this particular class using fissile fuel.

  7. Velocity synchronization of multi-agent systems with mismatched parameters via sampled position data.

    PubMed

    Sun, Wen; Huang, Chunli; Lü, Jinhu; Li, Xiong; Chen, Shihua

    2016-02-01

    Power systems are special multi-agent systems with nonlinear coupling function and symmetric structures. This paper extends these systems to a class of multi-agent systems with mismatched parameters, linear coupling function, and asymmetric structures and investigates their velocity synchronization via sampled position data. The dynamics of the agents is adopted as that of generators with mismatched parameters, while the system structures are supposed to be complex. Two distributed linear consensus protocols are designed, respectively, for multi-agent systems without or with communication delay. Necessary and sufficient conditions based on the sampling period, the mismatched parameters, the delay, and the nonzero eigenvalues of the Laplacian matrix are established. It is shown that velocity synchronization of multi-agent systems with mismatched parameters can be achieved if the sampled period is chosen appropriately. Simulations are given to illustrate the effectiveness of the theoretical results.

  8. A Novel Network Attack Audit System based on Multi-Agent Technology

    NASA Astrophysics Data System (ADS)

    Jianping, Wang; Min, Chen; Xianwen, Wu

    A network attack audit system which includes network attack audit Agent, host audit Agent and management control center audit Agent is proposed. And the improved multi-agent technology is carried out in the network attack audit Agent which has achieved satisfactory audit results. The audit system in terms of network attack is just in-depth, and with the function improvement of network attack audit Agent, different attack will be better analyzed and audit. In addition, the management control center Agent should manage and analyze audit results from AA (or HA) and audit data on time. And the history files of network packets and host log data should also be audit to find deeper violations that cannot be found in real time.

  9. Characterization of Estrogen-Receptor-Targeted Contrast-Agents in Solution, Breast Cancer Cells and Tumors in vivo

    PubMed Central

    Pais, Adi; Biton, Inbal Eti; Margalit, Raanan; Degani, Hadassa

    2012-01-01

    The estrogen receptor (ER) is a major prognostic biomarker of breast cancer, currently determined in surgical specimens by immunohistochemistry. Two new ER targeted probes, pyridine-tetra-acetate-Gd chelate (PTA-Gd) conjugated either to 17β-estradiol (EPTA-Gd) or to tamoxifen (TPTA-Gd), were explored as contrast agents for molecular imaging of ER. In solution both probes exhibited a micromolar ER binding-affinity, fast water exchange-rate (~107s−1) and water proton-relaxivity of 4.7 to 6.8 mM−1s−1. In human breast cancer cells, both probes acted as estrogen agonists and enhanced the water protons T1 relaxation-rate and relaxivity in ER-positive as compared to ER-negative cells, with EPTA-Gd showing a higher ER-specific relaxivity than TPTA-Gd. In studies of breast cancer tumors in vivo EPTA-Gd induced the highest enhancement in ER-positive tumors as compared to ER-negative tumors and muscle tissue, enabling in vivo detection of ER. TPTA-Gd demonstrated the highest enhancement in muscle tissue indicating non specific interaction of this agent with muscle components. The extracellular contrast agents, PTA-Gd and GdDTPA, showed no difference in the perfusion capacity of ER-positive and negative tumors confirming the specific interaction of EPTA-Gd with ER. These findings lay a basis for the molecular imaging of the estrogen receptor using EPTA-Gd as a template for further developments. PMID:22887470

  10. Irradiating or autoclaving chitosan/polyol solutions: effect on thermogelling chitosan-beta-glycerophosphate systems.

    PubMed

    Jarry, Claire; Leroux, Jean-Christophe; Haeck, Jonathan; Chaput, Cyril

    2002-10-01

    The effects of steam sterilization and gamma-irradiation on chitosan and thermogelling chitosan-beta-glycerophosphate (GP) solutions containing polyol additives were investigated. The selected polyols were triethylene glycol, glycerol, sorbitol, glucose and poly(ethylene glycol) (PEG). They were incorporated to chitosan solutions prior to sterilization in a proportion ranging from 1 to 5% (w/v). The solutions were characterized with respect to their viscosity, thermogelling properties, compressive stress relaxation behavior and chitosan degradation. All polyols reduced the autoclaving-induced viscosity loss and had a positive impact on the solution thermogelling properties and compressive performance of the gels. Steam sterilization in the presence of glucose resulted in a substantial increase in the solution viscosity and gel strength. This was associated with a strong discoloration suggesting chemical alteration of the system. PEG was the most effective agent in preventing hydrolytic degradation of chitosan chains. Gamma-irradiation strongly decreased the chitosan solution viscosity regardless of the presence of additives, even when sterilization was carried out at -80 degrees C. Moreover, the thermogelling properties were dramatically altered, and thus, gamma-irradiation would not be an appropriate method to sterilize chitosan solutions. In conclusion, polyols are potentially useful additive to maximise the viscoelastic and mechanical properties of chitosan-GP after steam sterilization.

  11. A Real-Time Multi-Agent System Architecture for E-Commerce Applications

    DTIC Science & Technology

    2000-12-01

    1 A Real-Time Multi-Agent System Architecture for E - Commerce Applications* Lisa Cingiser DiPippo, Victor Fay-Wolfe, Lekshmi Nair, Ethan Hodys and...2000 to 00-00-2000 4. TITLE AND SUBTITLE A Real-Time Multi-Agent System Architecture for E - Commerce Applications 5a. CONTRACT NUMBER 5b. GRANT...develop real-time e - commerce agent applications such as the stock trading system described throughout the paper. It provides agents with the ability to

  12. Magnesium hydroxide as the neutralizing agent for radioactive hydrochloric acid solutions

    SciTech Connect

    Palmer, M.J.; Fife, K.W.

    1995-10-01

    The current technology at Los Alamos for removing actinides from acidic chloride waste streams is precipitation with approximately 10 M potassium hydroxide. Although successful, there are many inherent drawbacks to this precipitation technique which will be detailed in this paper. Magnesium hydroxide (K{sub sp} = 1.3 x 10{sup -11}) has limited solubility in water and as a result of the common ion effect, cannot generate a filtrate with a pH greater than 9. At a pH of 9, calcium (K{sub sp} = 5.5 x 10{sup -6}) will not coprecipitate as the hydroxide. This is an important factor since many acidic chloride feeds to hydroxide precipitation contain significant amounts of calcium. In addition, neutralization with Mg(OH){sub 2} produces a more filterable precipitate because neutralization occurs as the Mg(OH){sub 2} is dissolved by the acid rather than as a result of the much faster liquid/liquid reaction of KOH with the waste acid. This slower solid/liquid reaction allows time for crystal growth to occur and produces more easily filterable precipitates. On the other hand, neutralization of spent acid with strong KOH that yields numerous hydroxide ions in solution almost instantaneously forming a much larger volume of small crystallites that result in gelatinous, slow-filtering precipitates. Magnesium hydroxide also offers a safety advantage. Although mildly irritating, it is a weak base and safe and easy to handle. From a waste minimization perspective, Mg(OH){sub 2} offers many advantages. First, the magnesium hydroxide is added as a solid. This step eliminates the diluent water used in KOH neutralizations. Secondly, because the particle size of the precipitate is larger, more actinides are caught on the filter paper resulting in a smaller amount of actinide being transferred to the TA-50 Liquid Waste Treatment Facility. Third, the amount of solids that must be reprocessed is significantly smaller resulting in less waste generation from the downstream processes.

  13. Removal of Hg(II) from aqueous solution using sodium humate as heavy metal capturing agent.

    PubMed

    Wang, Shixiang; Liu, Yong; Fan, Qin; Zhou, Anlan; Fan, Lu; Mu, Yulan

    2016-12-01

    An environmental friendly and economic natural biopolymer-sodium humate (HA-Na) was used to capture Hg(II) from aqueous solutions, and the trapped Hg(II) (HA-Na-Hg) was then removed by aluminium coagulation. The best Hg(II) capturing performance (90.60%) was observed under the following conditions: initial pH of 7.0, coagulation pH of 6.0, HA-Na dosage of 5.0 g L(-1), Al2(SO4)3.18H2O dosage of 4.0 g L(-1), initial Hg(II) concentration of 50 mg L(-1) and capturing time of 30 min. The HA-Na compositions with the molecular weight beyond 70 kDa showed the most intense affinity toward Hg(II). The results showed that the reaction equilibrium was achieved within 10 min (pH 7.0), and could be well fitted by the pseudo-second-order kinetics model. The capturing process could be well described by the Langmuir isotherm model and the maximum capturing capacity of Hg(II) was high up to 9.80 mg g(-1) at 298 K (pH 7.0). The Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS) analysis showed that the redox reaction between Hg(II) and HA-Na and the coordination reaction of carboxyl and hydroxy groups of HA-Na with Hg(II) were responsible for Hg(II) removal. The successive regeneration experiment showed that the capturing efficiency of humates for Hg(II) was maintained at about 51% after five capture-regeneration recycles.

  14. Distributed formation output regulation of switching heterogeneous multi-agent systems

    NASA Astrophysics Data System (ADS)

    Wang, Xiaoli

    2013-11-01

    In this article, the distributed formation output regulation problem of linear heterogeneous multi-agent systems with uncertainty under switching topology is considered. It is a generalised framework for multi-agent coordination problems, which contains or concerns a variety of important multi-agent problems in a quite unified way. Its background includes active leader following formation for the agents to maintain desired relative distances and orientations to the leader with a predefined trajectory, and multi-agent formation with environmental inputs. With the help of canonical internal model we design a distributed dynamic output feedback to handle the distributed formation output regulation problem.

  15. Combining Multi-Agent Systems and Wireless Sensor Networks for Monitoring Crop Irrigation.

    PubMed

    Villarrubia, Gabriel; Paz, Juan F De; Iglesia, Daniel H De La; Bajo, Javier

    2017-08-02

    Monitoring mechanisms that ensure efficient crop growth are essential on many farms, especially in certain areas of the planet where water is scarce. Most farmers must assume the high cost of the required equipment in order to be able to streamline natural resources on their farms. Considering that many farmers cannot afford to install this equipment, it is necessary to look for more effective solutions that would be cheaper to implement. The objective of this study is to build virtual organizations of agents that can communicate between each other while monitoring crops. A low cost sensor architecture allows farmers to monitor and optimize the growth of their crops by streamlining the amount of resources the crops need at every moment. Since the hardware has limited processing and communication capabilities, our approach uses the PANGEA architecture to overcome this limitation. Specifically, we will design a system that is capable of collecting heterogeneous information from its environment, using sensors for temperature, solar radiation, humidity, pH, moisture and wind. A major outcome of our approach is that our solution is able to merge heterogeneous data from sensors and produce a response adapted to the context. In order to validate the proposed system, we present a case study in which farmers are provided with a tool that allows us to monitor the condition of crops on a TV screen using a low cost device.

  16. Combining Multi-Agent Systems and Wireless Sensor Networks for Monitoring Crop Irrigation

    PubMed Central

    Villarrubia, Gabriel; De Paz, Juan F.; De La Iglesia, Daniel H.; Bajo, Javier

    2017-01-01

    Monitoring mechanisms that ensure efficient crop growth are essential on many farms, especially in certain areas of the planet where water is scarce. Most farmers must assume the high cost of the required equipment in order to be able to streamline natural resources on their farms. Considering that many farmers cannot afford to install this equipment, it is necessary to look for more effective solutions that would be cheaper to implement. The objective of this study is to build virtual organizations of agents that can communicate between each other while monitoring crops. A low cost sensor architecture allows farmers to monitor and optimize the growth of their crops by streamlining the amount of resources the crops need at every moment. Since the hardware has limited processing and communication capabilities, our approach uses the PANGEA architecture to overcome this limitation. Specifically, we will design a system that is capable of collecting heterogeneous information from its environment, using sensors for temperature, solar radiation, humidity, pH, moisture and wind. A major outcome of our approach is that our solution is able to merge heterogeneous data from sensors and produce a response adapted to the context. In order to validate the proposed system, we present a case study in which farmers are provided with a tool that allows us to monitor the condition of crops on a TV screen using a low cost device. PMID:28767089

  17. Influence of mitochondrion-toxic agents on the cardiovascular system.

    PubMed

    Finsterer, Josef; Ohnsorge, Peter

    2013-12-01

    Cardiovascular disease may be induced or worsened by mitochondrion-toxic agents. Mitochondrion-toxic agents may be classified as those with or without a clinical effect, those which induce cardiac disease only in humans or animals or both, as prescribed drugs, illicit drugs, exotoxins, or nutritiants, as those which affect the heart exclusively or also other organs, as those which are effective only in patients with a mitochondrial disorder or cardiac disease or also in healthy subjects, or as solid, liquid, or volatile agents. In humans, cardiotoxic agents due to mitochondrial dysfunction include anthracyclines (particularly doxorubicin), mitoxantrone, cyclophosphamide, cisplatin, fluorouracil, imatinib, bortezomib, trastuzumab, arsenic trioxide, cyclosporine-A, zidovudine, lamotrigine, glycosides, lidocain, isoproterenol, nitroprusside, pivalic acid, alcohol, cocaine, pesticides, cadmium, mycotoxins, cyanotoxins, meat meal, or carbon monoxide. Even more agents exhibit cardiac abnormalities due to mitochondrion-toxicity only in animals or tissue cultures. The mitochondrion-toxic effect results from impairment of the respiratory chain, the oxidative phosphorylation, the Krebs cycle, or the β-oxidation, from decrease of the mitochondrion-membrane potential, from increased oxidative stress, reduced anti-oxidative capacity, or from induction of apoptosis. Cardiac abnormalities induced via these mechanisms include cardiomyopathy, myocarditis, coronary heart disease, arrhythmias, heart failure, or Takotsubo syndrome. Discontinuation of the cardiotoxic agent results in complete recovery in the majority of the cases. Antioxidants and nutritiants may be of additional help. Particularly coenzyme-Q, riboflavin, vitamin-E, vitamin-C, L-carnitine, vitamin-D, thiamin, folic acid, omega-3 fatty acids, and D-ribose may alleviate mitochondrial cardiotoxic effects. Copyright © 2013 Elsevier Inc. All rights reserved.

  18. Closed-form solutions of performability. [in computer systems

    NASA Technical Reports Server (NTRS)

    Meyer, J. F.

    1982-01-01

    It is noted that if computing system performance is degradable then system evaluation must deal simultaneously with aspects of both performance and reliability. One approach is the evaluation of a system's performability which, relative to a specified performance variable Y, generally requires solution of the probability distribution function of Y. The feasibility of closed-form solutions of performability when Y is continuous are examined. In particular, the modeling of a degradable buffer/multiprocessor system is considered whose performance Y is the (normalized) average throughput rate realized during a bounded interval of time. Employing an approximate decomposition of the model, it is shown that a closed-form solution can indeed be obtained.

  19. Fundamental solutions for stationary Stokes systems with measurable coefficients

    NASA Astrophysics Data System (ADS)

    Choi, Jongkeun; Yang, Minsuk

    2017-10-01

    We establish the existence and the pointwise bound of the fundamental solution for the stationary Stokes system with measurable coefficients in the whole space Rd, d ≥ 3, under the assumption that weak solutions of the system are locally Hölder continuous. We also discuss the existence and the pointwise bound of the Green function for the Stokes system with measurable coefficients on Ω, where Ω is an unbounded domain such that the divergence equation is solvable. Such a domain includes, for example, half space and an exterior domain.

  20. Complex groundwater flow systems as traveling agent models

    PubMed Central

    Padilla, Pablo; Escolero, Oscar; González, Tomas; Morales-Casique, Eric; Osorio-Olvera, Luis

    2014-01-01

    Analyzing field data from pumping tests, we show that as with many other natural phenomena, groundwater flow exhibits complex dynamics described by 1/f power spectrum. This result is theoretically studied within an agent perspective. Using a traveling agent model, we prove that this statistical behavior emerges when the medium is complex. Some heuristic reasoning is provided to justify both spatial and dynamic complexity, as the result of the superposition of an infinite number of stochastic processes. Even more, we show that this implies that non-Kolmogorovian probability is needed for its study, and provide a set of new partial differential equations for groundwater flow. PMID:25337455

  1. Complex groundwater flow systems as traveling agent models.

    PubMed

    López Corona, Oliver; Padilla, Pablo; Escolero, Oscar; González, Tomas; Morales-Casique, Eric; Osorio-Olvera, Luis

    2014-01-01

    Analyzing field data from pumping tests, we show that as with many other natural phenomena, groundwater flow exhibits complex dynamics described by 1/f power spectrum. This result is theoretically studied within an agent perspective. Using a traveling agent model, we prove that this statistical behavior emerges when the medium is complex. Some heuristic reasoning is provided to justify both spatial and dynamic complexity, as the result of the superposition of an infinite number of stochastic processes. Even more, we show that this implies that non-Kolmogorovian probability is needed for its study, and provide a set of new partial differential equations for groundwater flow.

  2. Automated volumetric analysis for comparison of oral sulfate solution (SUPREP) with established cathartic agents at CT colonography.

    PubMed

    Bannas, Peter; Bakke, Joshua; Patrick, James L; Pickhardt, Perry J

    2015-01-01

    To objectively compare residual colonic fluid volume and attenuation of oral sulfate solution (OSS) with four different established cathartic regimens using an automated volumetric software tool at CT colonography (CTC). This HIPAA-compliant study had institutional review board approval. Volumetric analysis of residual contrast-tagged colonic fluid was performed on CTC studies in 263 adults (mean age 60.1 years; 137M/126F) using an automated volumetric software tool. Twenty-three patients receiving 177 mL OSS (SUPREP; single-bottle purgation) were compared with 60 patients each receiving 45 mL sodium phosphate (NaP), 90 mL NaP (2× NaP), 592 mL (two bottles) magnesium citrate (MgC), and 4,000 mL polyethylene glycol (PEG). All patients received oral contrast cleansing after catharsis. Data were analyzed with unpaired t test with Welch correction and F test. The mean volume of residual colonic fluid was less with OSS (125 ± 60 mL) than for established cathartic agents: 2× NaP (206 ± 125 mL, P < 0.0001), MgC (184 ± 125 mL, P < 0.01), PEG (166 ± 114 mL, P < 0.05), and NaP (165 ± 135 mL, P = 0.067). Variance of volumes was also significantly lower for OSS (range 28-251 mL) than for established agents (range 4-853 mL) (all P < 0.01). Mean fluid attenuation was higher with OSS (956 ± 168 HU) than for established agents (all P < 0.05): 2× NaP (455 ± 191 HU), MgC (691 ± 154 HU), NaP (779 ± 127 HU), and PEG (843 ± 193 HU). Automated volumetry allows rapid objective assessment of bowel preparation quality at CTC. Purgation with the novel oral sulfate solution (SUPREP) consistently resulted in less residual colonic fluid and higher fluid attenuation compared with established cathartic regimens.

  3. Influence of preparation method on itraconazole oral solutions using cyclodextrins as complexing agents.

    PubMed

    Holvoet, C; Vander Heyden, Y; Plaizier-Vercammen, J

    2007-07-01

    In the literature, solubility values of itraconazole complexed with 2-hydroxypropyl-beta-cyclodextrin (HP-beta-CD) were found which were still much too low to obtain the target concentration of 1 g itraconazole/100 ml, the concentration of the marketed itraconazole formulation Sporanox (Janssen Pharmaceutica). Therefore, we compared two preparation methods: the classical and the dissolving method to investigate if the method of preparation can have an influence on the solubility of itraconazole complexed with cyclodextrin (CD). With the classical method, the active compound and the CDs are jointly dissolved with a co-solvent, propylene glycol, in water. With the dissolving method, the active compound is first dissolved separately in a solvent in which it dissolves well, while the CDs are dissolved in water, before mixing. Three different CDs were used and compared for their complexing capacity with itraconazole. The complex formation of itraconazole with HP-beta-CD, sulfobutylether-7-beta-cyclodextrin (SBE-7-beta-CD) and maltosyl-beta-cyclodextrin (malt-beta-CD) was investigated at pH 2, in the presence of 10% propylene glycol for an oral solution. These three CDs were chosen as they can also serve in formulations for parenteral use. The method of preparation had an important influence on the complex formation. With the dissolving method, a much higher solubility of itraconazole was obtained using the same CD concentration than with the classical method. Inclusion capacity obtained with the dissolving method was comparable for HP-beta-CD and SBE-7-beta-CD: 1 g itraconazole/100 ml of 25% HP-beta-CD or of 30% SBE-7-beta-CD. In 100 ml of 40% malt-beta-CD only about 500 mg of itraconazole could be dissolved. With the classical method only around 160 mg itraconazole could be dissolved with 100 ml 40 % HP-beta-CD or SBE-7-beta-CD. Due to the fast preparation, once the CD amount is known by pretests, the dissolving method shows also an advantage for industrial production.

  4. Solution of a system of dual integral equations.

    NASA Technical Reports Server (NTRS)

    Buell, J.; Kagiwada, H.; Kalaba, R.; Ruspini, E.; Zagustin, E.

    1972-01-01

    The solution of a presented system of differential equations with initial values is shown to satisfy a system of dual integral equations of a type appearing in the study of axisymmetric problems of potential theory. Of practical interest are possible applications in biomechanics, particularly, for the case of trauma due to impact.

  5. Integrated Learning Systems: The Problems with the Solution.

    ERIC Educational Resources Information Center

    Bentley, Edward

    1991-01-01

    Discusses problems with integrated learning systems (ILSs) in the schools, noting they are still an unproven solution to problems in education plagued by many serious limitations. The article recommends dealing with the fundamental problems of the educational system before investing time and money in ILS. (SM)

  6. Effect of microbial contamination and pH changes in storage solutions during in vitro assays of bonding agents.

    PubMed

    Fotos, P G; Diaz-Arnold, A M; Williams, V D

    1990-07-01

    A study of pH changes in, and microbial colonization of, storage solutions being utilized during an in vitro evaluation of luting agent solubility has been made. Microbial growth in storage solutions was observed to occur at as high as 10(5) colony-forming units (cfu)/mL after seven days' incubation. A strong time-dependent inverse correlation between pH and cfu was found, with the pH dropping to as low as 5.3 (p less than 0.01). Decreases in pH were not found in presterilized control samples (p less than 0.05). Further, it was demonstrated that presterilization with ethylene oxide or the addition of respiratory inhibitors prevented both microbial colonization and the pH drop when compared with controls (p less than 0.001). These data suggest that studies of dental materials which include incubations in various fluids should be controlled for the potential effects of micro-organisms and their effect on pH.

  7. A Multi-Agent System for Tracking the Intent of Surface Contacts in Ports and Waterways

    DTIC Science & Technology

    2005-03-01

    identify asymmetric maritime threats in port and waterways. Each surface track is monitored by a compound multi - agent system that comprise of the several...intent models, each containing a nested multi - agent system . The attributes that define intent models of friendly, neutral, unknown and potentially

  8. Research of negotiation in network trade system based on multi-agent

    NASA Astrophysics Data System (ADS)

    Cai, Jun; Wang, Guozheng; Wu, Haiyan

    2009-07-01

    A construction and implementation technology of network trade based on multi-agent is described in this paper. First, we researched the technology of multi-agent, then we discussed the consumer's behaviors and the negotiation between purchaser and bargainer which emerges in the traditional business mode and analysed the key technology to implement the network trade system. Finally, we implement the system.

  9. Retention of radicular posts varying the application technique of the adhesive system and luting agent.

    PubMed

    Fonseca, Tabajara Sabbag; Alfredo, Edson; Vansan, Luiz Pascoal; Silva, Ricardo Gariba; Sousa, Yara T Correa Silva; Saquy, Paulo César; Sousa-Neto, Manoel D

    2006-01-01

    This study evaluated in vitro the retention of intracanal cast posts cemented with dual-cure resin varying the application method of the primer/adhesive solution and luting agent in the prosthetic space prepared to receive the posts. Sixty endodontically treated maxillary canines had their crowns discarded, and their roots were embedded in acrylic resin. The prosthetic spaces were prepared with Largo burs mounted on a low-speed handpiece coupled to a parallelometer in order to maintain length and diameter of intraradicular posts constant and to guarantee that the preparations were parallel after casting. Two groups (n = 30) were randomly formed according to the device used to apply the adhesive system: microbrush or standard bristle brush (control). Each group was divided into 3 subgroups (n = 10) according to the technique used to place the luting agent into the root canal: using only a lentulo spiral before setting the post, applying it onto the post surface, or combining both methods. After 72 hours, the tensile force required to dislodge each post was determined by a universal testing machine (Instron 4444) set at a speed of 1 mm/min. The results indicated that the use of the microbrush yielded higher bond strength values (0.1740 +/- 0.04 kN) than those recorded for the bristle brush tip (0.1369 +/- 0.04 kN, p < 0.001). Bonferroni's test demonstrated a higher retention (p < 0.001) in radicular post cemented with the technique that combined both methods (lentulo + post: 0.1787 +/- 0.03 kN) than that obtained with lentulo (0.1461 +/- 0.065 kN) or post (0.1416 +/- 0.03 kN) alone. The interactions between the adhesive system and luting agent application techniques presented statistical difference (p < 0.001). It was concluded that the best performance in terms of tensile strength among the tested conditions was obtained when the adhesive system was applied with a microbrush and the luting agent was taken into the root canal with lentulo spirals alone (0.1961 +/- 0

  10. Evaluation of Decontamination Systems Challenged With Nerve Agents

    DTIC Science & Technology

    2006-11-01

    may have contributed to the Gulf War Syndrome (Winkenwerder, 2000). The most notable use of nerve agents occurred in 1995 when a Japanese terrorist...were sheared with Oster brand animal clippers , blade #40, and anesthetized with a combination of 32 mg/ml ketamine and 4 mg/ml xylazine in saline

  11. Modeling of a production system using the multi-agent approach

    NASA Astrophysics Data System (ADS)

    Gwiazda, A.; Sękala, A.; Banaś, W.

    2017-08-01

    The method that allows for the analysis of complex systems is a multi-agent simulation. The multi-agent simulation (Agent-based modeling and simulation - ABMS) is modeling of complex systems consisting of independent agents. In the case of the model of the production system agents may be manufactured pieces set apart from other types of agents like machine tools, conveyors or replacements stands. Agents are magazines and buffers. More generally speaking, the agents in the model can be single individuals, but you can also be defined as agents of collective entities. They are allowed hierarchical structures. It means that a single agent could belong to a certain class. Depending on the needs of the agent may also be a natural or physical resource. From a technical point of view, the agent is a bundle of data and rules describing its behavior in different situations. Agents can be autonomous or non-autonomous in making the decision about the types of classes of agents, class sizes and types of connections between elements of the system. Multi-agent modeling is a very flexible technique for modeling and model creating in the convention that could be adapted to any research problem analyzed from different points of views. One of the major problems associated with the organization of production is the spatial organization of the production process. Secondly, it is important to include the optimal scheduling. For this purpose use can approach multi-purposeful. In this regard, the model of the production process will refer to the design and scheduling of production space for four different elements. The program system was developed in the environment NetLogo. It was also used elements of artificial intelligence. The main agent represents the manufactured pieces that, according to previously assumed rules, generate the technological route and allow preprint the schedule of that line. Machine lines, reorientation stands, conveyors and transport devices also represent the

  12. Global stability and exact solution of an arbitrary-solute nonlinear cellular mass transport system.

    PubMed

    Benson, James D

    2014-12-01

    The prediction of the cellular state as a function of extracellular concentrations and temperatures has been of interest to physiologists for nearly a century. One of the most widely used models in the field is one where mass flux is linearly proportional to the concentration difference across the membrane. These fluxes define a nonlinear differential equation system for the intracellular state, which when coupled with appropriate initial conditions, define the intracellular state as a function of the extracellular concentrations of both permeating and nonpermeating solutes. Here we take advantage of a reparametrization scheme to extend existing stability results to a more general setting and to a develop analytical solutions to this model for an arbitrary number of extracellular solutes.

  13. What Learning Systems do Intelligent Agents Need? Complementary Learning Systems Theory Updated.

    PubMed

    Kumaran, Dharshan; Hassabis, Demis; McClelland, James L

    2016-07-01

    We update complementary learning systems (CLS) theory, which holds that intelligent agents must possess two learning systems, instantiated in mammalians in neocortex and hippocampus. The first gradually acquires structured knowledge representations while the second quickly learns the specifics of individual experiences. We broaden the role of replay of hippocampal memories in the theory, noting that replay allows goal-dependent weighting of experience statistics. We also address recent challenges to the theory and extend it by showing that recurrent activation of hippocampal traces can support some forms of generalization and that neocortical learning can be rapid for information that is consistent with known structure. Finally, we note the relevance of the theory to the design of artificial intelligent agents, highlighting connections between neuroscience and machine learning. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. Design and Simulation of Material-Integrated Distributed Sensor Processing with a Code-Based Agent Platform and Mobile Multi-Agent Systems

    PubMed Central

    Bosse, Stefan

    2015-01-01

    Multi-agent systems (MAS) can be used for decentralized and self-organizing data processing in a distributed system, like a resource-constrained sensor network, enabling distributed information extraction, for example, based on pattern recognition and self-organization, by decomposing complex tasks in simpler cooperative agents. Reliable MAS-based data processing approaches can aid the material-integration of structural-monitoring applications, with agent processing platforms scaled to the microchip level. The agent behavior, based on a dynamic activity-transition graph (ATG) model, is implemented with program code storing the control and the data state of an agent, which is novel. The program code can be modified by the agent itself using code morphing techniques and is capable of migrating in the network between nodes. The program code is a self-contained unit (a container) and embeds the agent data, the initialization instructions and the ATG behavior implementation. The microchip agent processing platform used for the execution of the agent code is a standalone multi-core stack machine with a zero-operand instruction format, leading to a small-sized agent program code, low system complexity and high system performance. The agent processing is token-queue-based, similar to Petri-nets. The agent platform can be implemented in software, too, offering compatibility at the operational and code level, supporting agent processing in strong heterogeneous networks. In this work, the agent platform embedded in a large-scale distributed sensor network is simulated at the architectural level by using agent-based simulation techniques. PMID:25690550

  15. Design and simulation of material-integrated distributed sensor processing with a code-based agent platform and mobile multi-agent systems.

    PubMed

    Bosse, Stefan

    2015-02-16

    Multi-agent systems (MAS) can be used for decentralized and self-organizing data processing in a distributed system, like a resource-constrained sensor network, enabling distributed information extraction, for example, based on pattern recognition and self-organization, by decomposing complex tasks in simpler cooperative agents. Reliable MAS-based data processing approaches can aid the material-integration of structural-monitoring applications, with agent processing platforms scaled to the microchip level. The agent behavior, based on a dynamic activity-transition graph (ATG) model, is implemented with program code storing the control and the data state of an agent, which is novel. The program code can be modified by the agent itself using code morphing techniques and is capable of migrating in the network between nodes. The program code is a self-contained unit (a container) and embeds the agent data, the initialization instructions and the ATG behavior implementation. The microchip agent processing platform used for the execution of the agent code is a standalone multi-core stack machine with a zero-operand instruction format, leading to a small-sized agent program code, low system complexity and high system performance. The agent processing is token-queue-based, similar to Petri-nets. The agent platform can be implemented in software, too, offering compatibility at the operational and code level, supporting agent processing in strong heterogeneous networks. In this work, the agent platform embedded in a large-scale distributed sensor network is simulated at the architectural level by using agent-based simulation techniques.

  16. New approaches in agent-based modeling of complex financial systems

    NASA Astrophysics Data System (ADS)

    Chen, Ting-Ting; Zheng, Bo; Li, Yan; Jiang, Xiong-Fei

    2017-12-01

    Agent-based modeling is a powerful simulation technique to understand the collective behavior and microscopic interaction in complex financial systems. Recently, the concept for determining the key parameters of agent-based models from empirical data instead of setting them artificially was suggested. We first review several agent-based models and the new approaches to determine the key model parameters from historical market data. Based on the agents' behaviors with heterogeneous personal preferences and interactions, these models are successful in explaining the microscopic origination of the temporal and spatial correlations of financial markets. We then present a novel paradigm combining big-data analysis with agent-based modeling. Specifically, from internet query and stock market data, we extract the information driving forces and develop an agent-based model to simulate the dynamic behaviors of complex financial systems.

  17. Mobile Agents: A Distributed Voice-Commanded Sensory and Robotic System for Surface EVA Assistance

    NASA Technical Reports Server (NTRS)

    Clancey, William J.; Sierhuis, Maarten; Alena, Rick; Crawford, Sekou; Dowding, John; Graham, Jeff; Kaskiris, Charis; Tyree, Kim S.; vanHoof, Ronnie

    2003-01-01

    A model-based, distributed architecture integrates diverse components in a system designed for lunar and planetary surface operations: spacesuit biosensors, cameras, GPS, and a robotic assistant. The system transmits data and assists communication between the extra-vehicular activity (EVA) astronauts, the crew in a local habitat, and a remote mission support team. Software processes ("agents"), implemented in a system called Brahms, run on multiple, mobile platforms, including the spacesuit backpacks, all-terrain vehicles, and robot. These "mobile agents" interpret and transform available data to help people and robotic systems coordinate their actions to make operations more safe and efficient. Different types of agents relate platforms to each other ("proxy agents"), devices to software ("comm agents"), and people to the system ("personal agents"). A state-of-the-art spoken dialogue interface enables people to communicate with their personal agents, supporting a speech-driven navigation and scheduling tool, field observation record, and rover command system. An important aspect of the engineering methodology involves first simulating the entire hardware and software system in Brahms, and then configuring the agents into a runtime system. Design of mobile agent functionality has been based on ethnographic observation of scientists working in Mars analog settings in the High Canadian Arctic on Devon Island and the southeast Utah desert. The Mobile Agents system is developed iteratively in the context of use, with people doing authentic work. This paper provides a brief introduction to the architecture and emphasizes the method of empirical requirements analysis, through which observation, modeling, design, and testing are integrated in simulated EVA operations.

  18. Asymptotics of solutions of some nonlinear elliptic systems

    SciTech Connect

    Bidaut-Veron, M.F.; Raoux, T.

    1996-12-31

    This paper deals with the local and global behaviour of the positive solutions of the semilinear elliptic system in R{sup N} (N{ge}3) {Delta}u+{vert_bar}x{vert_bar}{sup {sigma}}u{sup q}v{sup p+1} =0, {Delta}v+{vert_bar}x{vert_bar}{sup {sigma}}u{sup q+1}v{sup p}=0, where {sigma},p,q{epsilon}R, and p,q>0. Our main results in the fact that the solutions satisfy Harnack inequality when Q = p+q+1<(N+2)/(N-2), which gives local estimates. Without this assumption on Q, we give the precise behaviour of the solutions, provided that these estimates are true. When Q < (N+2)/(N-2), the solutions can also present an anisotropic behaviour. 34 refs.

  19. Fault-Tolerant Consensus of Multi-Agent System With Distributed Adaptive Protocol.

    PubMed

    Chen, Shun; Ho, Daniel W C; Li, Lulu; Liu, Ming

    2015-10-01

    In this paper, fault-tolerant consensus in multi-agent system using distributed adaptive protocol is investigated. Firstly, distributed adaptive online updating strategies for some parameters are proposed based on local information of the network structure. Then, under the online updating parameters, a distributed adaptive protocol is developed to compensate the fault effects and the uncertainty effects in the leaderless multi-agent system. Based on the local state information of neighboring agents, a distributed updating protocol gain is developed which leads to a fully distributed continuous adaptive fault-tolerant consensus protocol design for the leaderless multi-agent system. Furthermore, a distributed fault-tolerant leader-follower consensus protocol for multi-agent system is constructed by the proposed adaptive method. Finally, a simulation example is given to illustrate the effectiveness of the theoretical analysis.

  20. A Distributed Ambient Intelligence Based Multi-Agent System for Alzheimer Health Care

    NASA Astrophysics Data System (ADS)

    Tapia, Dante I.; RodríGuez, Sara; Corchado, Juan M.

    This chapter presents ALZ-MAS (Alzheimer multi-agent system), an ambient intelligence (AmI)-based multi-agent system aimed at enhancing the assistance and health care for Alzheimer patients. The system makes use of several context-aware technologies that allow it to automatically obtain information from users and the environment in an evenly distributed way, focusing on the characteristics of ubiquity, awareness, intelligence, mobility, etc., all of which are concepts defined by AmI. ALZ-MAS makes use of a services oriented multi-agent architecture, called flexible user and services oriented multi-agent architecture, to distribute resources and enhance its performance. It is demonstrated that a SOA approach is adequate to build distributed and highly dynamic AmI-based multi-agent systems.

  1. Optimal and event-based networked control of physically interconnected systems and multi-agent systems

    NASA Astrophysics Data System (ADS)

    Demir, Ozan; Lunze, Jan

    2014-01-01

    Many interconnected systems like vehicle platoons or energy networks consist of similar or identical subsystems. The subsystem interconnections are either caused by the physical relations among the subsystems or have to be introduced by the controller to cope with cooperative control goals. This paper proposes strategies to reduce the complexity of the controller design problem (offline information reduction) and to reduce the amount of the system information, which is necessary for the implementation of the designed controller (online information reduction). It consists of two parts. The first part deals with the linear quadratic regulator (LQR) design problem for interconnected systems. A decomposition based on a state transformation is introduced, which allows to design the optimal controller for the interconnected system by considering modified subsystems separately. The proposed decomposition approach can be uniformly applied to multi-agent systems and physically interconnected systems. The second part of the paper introduces an event-based control strategy for multi-agent systems. The event-based control is a means to reduce the communication effort by invoking an information exchange among the subsystems only when the deviation between the estimated and current subsystem state exceeds an event threshold. An event-based controller is proposed, which mimics the continuous state-feedback controller with a desired precision. The relation between the event threshold and the approximation error is analysed.

  2. Adaptive Consensus Problem of Leader-Follower Multi-Agent System

    NASA Astrophysics Data System (ADS)

    Zhang, Qing; Chen, Shi-Hua; Guo, Wan-Li

    2010-10-01

    We consider the adaptive consensus problem for leader-follower multi-agent systems with time delay coupling. Under the condition that the interconnection graph of the agents is directed and balanced, a neighbor-based consensus protocol with adaptive feedback gain is proposed for the follower agents to track the leader. The stability is performed based on the Lyapunov stability theorem. Some simulation examples are provided to show the efficiency of the control scheme.

  3. Agent-based modeling of host–pathogen systems: The successes and challenges

    PubMed Central

    Bauer, Amy L.; Beauchemin, Catherine A.A.; Perelson, Alan S.

    2009-01-01

    Agent-based models have been employed to describe numerous processes in immunology. Simulations based on these types of models have been used to enhance our understanding of immunology and disease pathology. We review various agent-based models relevant to host–pathogen systems and discuss their contributions to our understanding of biological processes. We then point out some limitations and challenges of agent-based models and encourage efforts towards reproducibility and model validation. PMID:20161146

  4. The Architecture of Information Fusion System Ingreenhouse Wireless Sensor Network Based on Multi-Agent

    NASA Astrophysics Data System (ADS)

    Zhu, Wenting; Chen, Ming

    In view of current unprogressive situation of factory breeding in aquaculture, this article designed a standardized, informationized and intelligentized aquaculture system, proposed a information fusion architecture based on multi-agent in greenhouse wireless sensor network (GWSN), and researched mainly the structural characteristic of the four-classed information fusion based on distributed multi-agent and the method to construct the structure inside of every agent.

  5. Agents for replacement of NAD+/NADH system in enzymatic reactions

    DOEpatents

    Fish, Richard H.; Kerr, John B.; Lo, Christine H.

    2004-04-06

    Novel agents acting as co-factors for replacement of NAD(P).sup.+ /NAD(P)H co-enzyme systems in enzymatic oxido-reductive reactions. Agents mimicking the action of NAD(P).sup.+ /NAD(P)H system in enzymatic oxidation/reduction of substrates into reduced or oxidized products. A method for selection and preparation of the mimicking agents for replacement of NAD(P).sup.+ /NAD(P)H system and a device comprising co-factors for replacement of NAD(P).sup.+ /NAD(P)H system.

  6. Agent-based paradigm for integration of interactive cable television operations and business support systems

    NASA Astrophysics Data System (ADS)

    Wattawa, Scott

    1995-11-01

    Offering interactive services and data in a hybrid fiber/coax cable system requires the coordination of a host of operations and business support systems. New service offerings and network growth and evolution create never-ending changes in the network infrastructure. Agent-based enterprise models provide a flexible mechanism for systems integration of service and support systems. Agent models also provide a mechanism to decouple interactive services from network architecture. By using the Java programming language, agents may be made safe, portable, and intelligent. This paper investigates the application of the Object Management Group's Common Object Request Brokering Architecture to the integration of a multiple services metropolitan area network.

  7. Preprocessing Inconsistent Linear System for a Meaningful Least Squares Solution

    NASA Technical Reports Server (NTRS)

    Sen, Syamal K.; Shaykhian, Gholam Ali

    2011-01-01

    Mathematical models of many physical/statistical problems are systems of linear equations. Due to measurement and possible human errors/mistakes in modeling/data, as well as due to certain assumptions to reduce complexity, inconsistency (contradiction) is injected into the model, viz. the linear system. While any inconsistent system irrespective of the degree of inconsistency has always a least-squares solution, one needs to check whether an equation is too much inconsistent or, equivalently too much contradictory. Such an equation will affect/distort the least-squares solution to such an extent that renders it unacceptable/unfit to be used in a real-world application. We propose an algorithm which (i) prunes numerically redundant linear equations from the system as these do not add any new information to the model, (ii) detects contradictory linear equations along with their degree of contradiction (inconsistency index), (iii) removes those equations presumed to be too contradictory, and then (iv) obtain the minimum norm least-squares solution of the acceptably inconsistent reduced linear system. The algorithm presented in Matlab reduces the computational and storage complexities and also improves the accuracy of the solution. It also provides the necessary warning about the existence of too much contradiction in the model. In addition, we suggest a thorough relook into the mathematical modeling to determine the reason why unacceptable contradiction has occurred thus prompting us to make necessary corrections/modifications to the models - both mathematical and, if necessary, physical.

  8. Combination of crystalloid (glucose) and colloid (icodextrin) osmotic agents markedly enhances peritoneal fluid and solute transport during the long PD dwell.

    PubMed

    Freida, Philippe; Galach, Magda; Divino Filho, Jose C; Werynski, Andrzej; Lindholm, Bengt

    2007-01-01

    Fluid and sodium removal is often inadequate in peritoneal dialysis patients with high peritoneal solute transport rate, especially when residual renal function is declining. We studied the effects of using simultaneous crystalloid (glucose) and colloid (icodextrin) osmotic agents on the peritoneal transport of fluid, sodium, and other solutes during 15-hour single-dwell exchanges using 3.86% glucose, 7.5% icodextrin, and a combination fluid with 2.61% glucose and 6.8% icodextrin in 7 prevalent peritoneal dialysis patients with fast peritoneal solute transport rate. The combination fluid enhanced net ultrafiltration (mean 990 mL) and sodium removal (mean 158 mmol) compared with 7.5% icodextrin (mean net ultrafiltration 462 mL, mean net sodium removal 49 mmol). In contrast, the 3.86% glucose-based solution yielded negligible ultrafiltration (mean -85 mL) and sodium removal (mean 16 mmol). The combination solution resulted in significantly improved urea (+41%) and creatinine (+26%) clearances compared with 7.5% icodextrin. A solution containing both crystalloid (glucose 2.61%) and colloid (icodextrin 6.8%) osmotic agents enhanced fluid removal by twofold and sodium removal by threefold compared with 7.5% icodextrin solution during a dwell of 15 hours, indicating that such a combination solution could represent a new treatment option for anuric peritoneal dialysis patients with high peritoneal solute transport rate.

  9. An Approach for Autonomy: A Collaborative Communication Framework for Multi-Agent Systems

    NASA Technical Reports Server (NTRS)

    Dufrene, Warren Russell, Jr.

    2005-01-01

    Research done during the last three years has studied the emersion properties of Complex Adaptive Systems (CAS). The deployment of Artificial Intelligence (AI) techniques applied to remote Unmanned Aerial Vehicles has led the author to investigate applications of CAS within the field of Autonomous Multi-Agent Systems. The core objective of current research efforts is focused on the simplicity of Intelligent Agents (IA) and the modeling of these agents within complex systems. This research effort looks at the communication, interaction, and adaptability of multi-agents as applied to complex systems control. The embodiment concept applied to robotics has application possibilities within multi-agent frameworks. A new framework for agent awareness within a virtual 3D world concept is possible where the vehicle is composed of collaborative agents. This approach has many possibilities for applications to complex systems. This paper describes the development of an approach to apply this virtual framework to the NASA Goddard Space Flight Center (GSFC) tetrahedron structure developed under the Autonomous Nano Technology Swarm (ANTS) program and the Super Miniaturized Addressable Reconfigurable Technology (SMART) architecture program. These projects represent an innovative set of novel concepts deploying adaptable, self-organizing structures composed of many tetrahedrons. This technology is pushing current applied Agents Concepts to new levels of requirements and adaptability.

  10. Exact dynamics of stochastic linear delayed systems: Application to spatiotemporal coordination of comoving agents

    NASA Astrophysics Data System (ADS)

    McKetterick, Thomas John; Giuggioli, Luca

    2014-10-01

    Delayed dynamics result from finite transmission speeds of a signal in the form of energy, mass, or information. In stochastic systems the resulting lagged dynamics challenge our understanding due to the rich behavioral repertoire encompassing monotonic, oscillatory, and unstable evolution. Despite the vast literature, quantifying this rich behavior is limited by a lack of explicit analytic studies of high-dimensional stochastic delay systems. Here we fill this gap for systems governed by a linear Langevin equation of any number of delays and spatial dimensions with additive Gaussian noise. By exploiting Laplace transforms we are able to derive an exact time-dependent analytic solution of the Langevin equation. By using characteristic functionals we are able to construct the full time dependence of the multivariate probability distribution of the stochastic process as a function of the delayed and nondelayed random variables. As an application we consider interactions in animal collective movement that go beyond the traditional assumption of instantaneous alignment. We propose models for coordinated maneuvers of comoving agents applicable to recent empirical findings in pigeons and bats whereby individuals copy the heading of their neighbors with some delay. We highlight possible strategies that individual pairs may adopt to reduce the variance in their velocity difference and/or in their spatial separation. We also show that a minimum in the variance of the spatial separation at long times can be achieved with certain ratios of measurement to reaction delay.

  11. Negotiation Support Agent Based on Fuzzy Decision Making by Genetic Programming with the Coupled Chaos System

    NASA Astrophysics Data System (ADS)

    Matsumura, Koki; Goto, Michihiko; Hamamatsu, Yoshio

    This paper describes a negotiation agent system based on the fuzzy decision making. The method of seeking appropriate membership functions and a reasonable agreement point was examined by means of the genetic programming technique with the coupled chaos system, which is an intelligent principle. The negotiation rule is based on the negotiation model expressed by the utility theory in the process of decision making. And the concession process was modified with the opponent’s movement and the persistence of each negotiator. In order to search for a membership function more efficiently, the dynamic state of symbiosis between individuals, which was caused by the coupled chaos system, was taken advantage of. Then the effectiveness of the technique was examined by applying it to a practical negotiation case which needs cooperative decision making. As a result, the following findings were obtained. This technique helps discover practicable membership functions in a vast search area, and achieve the solution search with high efficiency. This technique is also considered to be applied to the negotiation support easily.

  12. Observer-based distributed consensus for general nonlinear multi-agent systems with interval control inputs

    NASA Astrophysics Data System (ADS)

    Zhang, Wentao; Liu, Yang

    2016-01-01

    In this paper, observer-based distributed consensus for general nonlinear multi-agent systems with interval control inputs under strongly connected balanced topology is encountered when the relative states of agents are unavailable or undesirable. Theoretical analysis method is further extended to the case of general nonlinear multi-agent systems under switching setting. Moreover, tracking problem on the leader-follower scenario is also explicitly investigated under a mutual assumption that the communication graph, which represents the interaction among agents, contains a directed spanning tree with the leader as its root. It is shown that the consensus for underlying considered multi-agent systems can be desirable as long as the data missing rate does not exceed a certain threshold. Finally, simulation examples are presented to effectively corroborate the analytical findings.

  13. Performance Consensus Problem of Multi-Agent Systems with Multiple State Variables

    NASA Astrophysics Data System (ADS)

    Hayashi, Naoki; Ushio, Toshimitsu

    A consensus problem has been studied in many fundamental and application fields to analyze coordinated behavior in multiagent systems. In a consensus problem, it is usually assumed that a state of each agent is scalar and all agents have an identical linear consensus protocol. We present a consensus problem of multi-agent systems where each agent has multiple state variables and a performance value evaluated by a nonlinear performance function according to its current state. We derive sufficient conditions for agents to achieve consensus on the performance value using an algebraic graph theory and the mean value theorem. We also consider an application of a performance consensus problem to resource allocation in soft real-time systems so as to achieve a fair QoS (Quality of Service) level.

  14. Finding sets of solutions to systems of nonlinear inequalities

    NASA Astrophysics Data System (ADS)

    Evtushenko, Yu. G.; Posypkin, M. A.; Rybak, L. A.; Turkin, A. V.

    2017-08-01

    The problem of approximating the set of all solutions to a system of nonlinear inequalities is studied. A method based on the concept of nonuniform coverings is proposed. It allows one to obtain an interior and exterior approximation of this set with a prescribed accuracy. The efficiency of the method is demonstrated by determining the workspace of a parallel robot.

  15. Systems Building; A Solution to the Cost Squeeze?

    ERIC Educational Resources Information Center

    Rogers, A. Robert

    1969-01-01

    A suggestion that the solution to today's high construction costs for library buildings is through systems building, the key to which is dimensional coordination - relating all the elements that go to make up a building in such a way that the parts will fit together with little or no alteration at the construction site. A supplementary…

  16. Systems Building; A Solution to the Cost Squeeze?

    ERIC Educational Resources Information Center

    Rogers, A. Robert

    1969-01-01

    A suggestion that the solution to today's high construction costs for library buildings is through systems building, the key to which is dimensional coordination - relating all the elements that go to make up a building in such a way that the parts will fit together with little or no alteration at the construction site. A supplementary…

  17. Collective Machine Learning: Team Learning and Classification in Multi-Agent Systems

    ERIC Educational Resources Information Center

    Gifford, Christopher M.

    2009-01-01

    This dissertation focuses on the collaboration of multiple heterogeneous, intelligent agents (hardware or software) which collaborate to learn a task and are capable of sharing knowledge. The concept of collaborative learning in multi-agent and multi-robot systems is largely under studied, and represents an area where further research is needed to…

  18. Collective Machine Learning: Team Learning and Classification in Multi-Agent Systems

    ERIC Educational Resources Information Center

    Gifford, Christopher M.

    2009-01-01

    This dissertation focuses on the collaboration of multiple heterogeneous, intelligent agents (hardware or software) which collaborate to learn a task and are capable of sharing knowledge. The concept of collaborative learning in multi-agent and multi-robot systems is largely under studied, and represents an area where further research is needed to…

  19. Object oriented image analysis based on multi-agent recognition system

    NASA Astrophysics Data System (ADS)

    Tabib Mahmoudi, Fatemeh; Samadzadegan, Farhad; Reinartz, Peter

    2013-04-01

    In this paper, the capabilities of multi-agent systems are used in order to solve object recognition difficulties in complex urban areas based on the characteristics of WorldView-2 satellite imagery and digital surface model (DSM). The proposed methodology has three main steps: pre-processing of dataset, object based image analysis and multi-agent object recognition. Classified regions obtained from object based image analysis are used as input datasets in the proposed multi-agent system in order to modify/improve results. In the first operational level of the proposed multi-agent system, various kinds of object recognition agents modify initial classified regions based on their spectral, textural and 3D structural knowledge. Then, in the second operational level, 2D structural knowledge and contextual relations are used by agents for reasoning and modification. Evaluation of the capabilities of the proposed object recognition methodology is performed on WorldView-2 imagery over Rio de Janeiro (Brazil) which has been collected in January 2010. According to the obtained results of the object based image analysis process, contextual relations and structural descriptors have high potential to modify general difficulties of object recognition. Using knowledge based reasoning and cooperative capabilities of agents in the proposed multi-agent system in this paper, most of the remaining difficulties are decreased and the accuracy of object based image analysis results is improved for about three percent.

  20. Coherent pulsed excitation of degenerate multistate systems: Exact analytic solutions

    SciTech Connect

    Kyoseva, E. S.; Vitanov, N. V.

    2006-02-15

    We show that the solution of a multistate system composed of N degenerate lower (ground) states and one upper (excited) state can be reduced by using the Morris-Shore transformation to the solution of a two-state system involving only the excited state and a (bright) superposition of ground states. In addition, there are N-1 dark states composed of ground states. We use this decomposition to derive analytical solutions for degenerate extensions of the most popular exactly soluble models: the resonance solution, the Rabi, Landau-Zener, Rosen-Zener, Allen-Eberly, and Demkov-Kunike models. We suggest various applications of the multistate solutions, for example, as tools for creating multistate coherent superpositions by generalized resonant {pi} pulses. We show that such generalized {pi} pulses can occur even when the upper state is far off resonance, at specific detunings, which makes it possible to operate in the degenerate ground-state manifold without populating the (possibly lossy) upper state, even transiently.

  1. Complexity of Dense Linear System Solution on a Multiprocessor Ring.

    DTIC Science & Technology

    1985-01-01

    Lawrie and Sameh [4] present a technique for solving symmetric positive definite banded systems, which is a generalization of a method for tridiagonal...Numerical Linear Algebra, SIAM Review. 20 (1978), pp. 740-777. [4] D. Lawrie, A.H. Sameh , The Computation and Communication Complexity of a Parallel Banded...409. [7] , Parallel, Iterative Solution of Sparse Linear Systems : Models and Architectures. Technical Report 84-35, ICASE, 1984. (81 A.H. Sameh , On

  2. Similarity solutions for systems arising from an Aedes aegypti model

    NASA Astrophysics Data System (ADS)

    Freire, Igor Leite; Torrisi, Mariano

    2014-04-01

    In a recent paper a new model for the Aedes aegypti mosquito dispersal dynamics was proposed and its Lie point symmetries were investigated. According to the carried group classification, the maximal symmetry Lie algebra of the nonlinear cases is reached whenever the advection term vanishes. In this work we analyze the family of systems obtained when the wind effects on the proposed model are neglected. Wide new classes of solutions to the systems under consideration are obtained.

  3. Workflow Agents vs. Expert Systems: Problem Solving Methods in Work Systems Design

    NASA Technical Reports Server (NTRS)

    Clancey, William J.; Sierhuis, Maarten; Seah, Chin

    2009-01-01

    During the 1980s, a community of artificial intelligence researchers became interested in formalizing problem solving methods as part of an effort called "second generation expert systems" (2nd GES). How do the motivations and results of this research relate to building tools for the workplace today? We provide an historical review of how the theory of expertise has developed, a progress report on a tool for designing and implementing model-based automation (Brahms), and a concrete example how we apply 2nd GES concepts today in an agent-based system for space flight operations (OCAMS). Brahms incorporates an ontology for modeling work practices, what people are doing in the course of a day, characterized as "activities." OCAMS was developed using a simulation-to-implementation methodology, in which a prototype tool was embedded in a simulation of future work practices. OCAMS uses model-based methods to interactively plan its actions and keep track of the work to be done. The problem solving methods of practice are interactive, employing reasoning for and through action in the real world. Analogously, it is as if a medical expert system were charged not just with interpreting culture results, but actually interacting with a patient. Our perspective shifts from building a "problem solving" (expert) system to building an actor in the world. The reusable components in work system designs include entire "problem solvers" (e.g., a planning subsystem), interoperability frameworks, and workflow agents that use and revise models dynamically in a network of people and tools. Consequently, the research focus shifts so "problem solving methods" include ways of knowing that models do not fit the world, and ways of interacting with other agents and people to gain or verify information and (ultimately) adapt rules and procedures to resolve problematic situations.

  4. The comparison of the use of holonic and agent-based methods in modelling of manufacturing systems

    NASA Astrophysics Data System (ADS)

    Foit, K.; Banaś, W.; Gwiazda, A.; Hryniewicz, P.

    2017-08-01

    The rapid evolution in the field of industrial automation and manufacturing is often called the 4th Industry Revolution. Worldwide availability of the internet access contributes to the competition between manufacturers, gives the opportunity for buying materials, parts and for creating the partnership networks, like cloud manufacturing, grid manufacturing (MGrid), virtual enterprises etc. The effect of the industry evolution is the need to search for new solutions in the field of manufacturing systems modelling and simulation. During the last decade researchers have developed the agent-based approach of modelling. This methodology have been taken from the computer science, but was adapted to the philosophy of industrial automation and robotization. The operation of the agent-based system depends on the simultaneous acting of different agents that may have different roles. On the other hand, there is the holon-based approach that uses the structures created by holons. It differs from the agent-based structure in some aspects, while the other ones are quite similar in both methodologies. The aim of this paper is to present the both methodologies and discuss the similarities and the differences. This may could help to select the optimal method of modelling, according to the considered problem and software resources.

  5. A multi-agent system approach for monitoring the prescription of restricted use antibiotics.

    PubMed

    Godo, L; Puyol-Gruart, J; Sabater, J; Torra, V; Barrufet, P; Fàbregas, X

    2003-03-01

    Hospitals have a specified set of antibiotics for restricted use (ARU), very expensive, which are only recommended for special pathologies. The pharmacy department daily checks the prescription of this kind of antibiotics since it is often the case that, after a careful analysis, one can get the same therapeutic effects by using normal antibiotics which are much cheaper and usually less aggressive. In this paper, we describe a multi-agent system to help in the revision of medical prescriptions containing antibiotics of restricted use. The proposed approach attaches an agent to each patient which is responsible of checking different medical aspects related to his/her prescribed therapy. A pharmacy agent is responsible for analyzing it and suggesting alternative antibiotic treatments. All these agents are integrated in a hospital distributed scenario composed by many different kinds of software and human agents. This patient-centered multi-agent scenario is specified using the design methodology of Electronic Institutions.

  6. Problems and solutions of the IFSMTF power and switch system

    SciTech Connect

    Wood, R.J.; Wintenberg, R.E.; Googe, J.M.; Nickels, L.E.

    1985-01-01

    Solutions have been found for the problems encountered with the coil power and switching systems of the International Fusion Superconducting Magnet Test Facility (IFSMTF). The coil power system provides the filtered dc sources (+- 12 V dc; 25,000 A) for charging and discharging the coils of the IFSMTF experiment. The switching system provides the means of transferring the coil current into a dump resistor when a rapid discharge of a coil is required due to a coil failure (quench) or other system abnormalities.

  7. Systemic solutions for multi-benefit water and environmental management.

    PubMed

    Everard, Mark; McInnes, Robert

    2013-09-01

    The environmental and financial costs of inputs to, and unintended consequences arising from narrow consideration of outputs from, water and environmental management technologies highlight the need for low-input solutions that optimise outcomes across multiple ecosystem services. Case studies examining the inputs and outputs associated with several ecosystem-based water and environmental management technologies reveal a range from those that differ little from conventional electro-mechanical engineering techniques through methods, such as integrated constructed wetlands (ICWs), designed explicitly as low-input systems optimising ecosystem service outcomes. All techniques present opportunities for further optimisation of outputs, and hence for greater cumulative public value. We define 'systemic solutions' as "…low-input technologies using natural processes to optimise benefits across the spectrum of ecosystem services and their beneficiaries". They contribute to sustainable development by averting unintended negative impacts and optimising benefits to all ecosystem service beneficiaries, increasing net economic value. Legacy legislation addressing issues in a fragmented way, associated 'ring-fenced' budgets and established management assumptions represent obstacles to implementing 'systemic solutions'. However, flexible implementation of legacy regulations recognising their primary purpose, rather than slavish adherence to detailed sub-clauses, may achieve greater overall public benefit through optimisation of outcomes across ecosystem services. Systemic solutions are not a panacea if applied merely as 'downstream' fixes, but are part of, and a means to accelerate, broader culture change towards more sustainable practice. This necessarily entails connecting a wider network of interests in the formulation and design of mutually-beneficial systemic solutions, including for example spatial planners, engineers, regulators, managers, farming and other businesses, and

  8. Systemic therapy with immunosuppressive agents and retinoids in hidradenitis suppurativa: a systematic review.

    PubMed

    Blok, J L; van Hattem, S; Jonkman, M F; Horváth, B

    2013-02-01

    Hidradenitis suppurativa (HS) is a difficult disease to treat. Although the pathogenesis of this inflammatory skin disease is largely unknown, the important role of the immune system has been demonstrated in both experimental and clinical studies. Clinicians are therefore increasingly prescribing systemic treatments with immunosuppressive agents, but the more traditionally used systemic retinoids, especially isotretinoin, also remain relatively common therapies. In order to provide an overview of all currently available systemic immunosuppressive agents and retinoids for the treatment of HS, a systematic search was performed using the Medline and Embase databases. All published papers concerning systemic retinoids or immunosuppressive treatments for HS in adults were included. The primary endpoints were the percentages of significant responders, moderate responders and nonresponders. Other endpoints were the relapse rate and adverse events. In total 87 papers were included, comprising 518 patients with HS who were treated with systemic retinoids, biological agents or another immunosuppressive agents, including colchicine, ciclosporin, dapsone or methotrexate. The highest response rates were observed with infliximab, adalimumab and acitretin. Overall, the quality of evidence was low and differed between the agents, making direct comparisons difficult. However, based on the amount of evidence, infliximab and adalimumab were the most effective agents. Acitretin was also effective in HS, although the quality of the evidence was low. The therapeutic effect of isotretinoin is questionable. Randomized controlled trials are needed to confirm the effectiveness of acitretin, and to identify the most effective immunosuppressive agents in HS. © 2012 The Authors. BJD © 2012 British Association of Dermatologists.

  9. A new two-component integrable system with peakon solutions

    PubMed Central

    Xia, Baoqiang; Qiao, Zhijun

    2015-01-01

    A new two-component system with cubic nonlinearity and linear dispersion: mt=bux+12[m(uv−uxvx)]x−12m(uvx−uxv),nt=bvx+12[n(uv−uxvx)]x+12n(uvx−uxv),m=u−uxx,n=v−vxx,where b is an arbitrary real constant, is proposed in this paper. This system is shown integrable with its Lax pair, bi-Hamiltonian structure and infinitely many conservation laws. Geometrically, this system describes a non-trivial one-parameter family of pseudo-spherical surfaces. In the case b=0, the peaked soliton (peakon) and multi-peakon solutions to this two-component system are derived. In particular, the two-peakon dynamical system is explicitly solved and their interactions are investigated in details. Moreover, a new integrable cubic nonlinear equation with linear dispersion mt=bux+12[m(|u|2−|ux|2)]x−12m(uux∗−uxu∗),m=u−uxx,is obtained by imposing the complex conjugate reduction v=u* to the two-component system. The complex-valued N-peakon solution and kink wave solution to this complex equation are also derived. PMID:25792956

  10. Balanced-Viscosity solutions for multi-rate systems

    NASA Astrophysics Data System (ADS)

    Mielke, Alexander; Rossi, Riccarda; Savaré, Giuseppe

    2016-06-01

    Several mechanical systems are modeled by the static momentum balance for the displacement u coupled with a rate-independent flow rule for some internal variable z. We consider a class of abstract systems of ODEs which have the same structure, albeit in a finite-dimensional setting, and regularize both the static equation and the rate-independent flow rule by adding viscous dissipation terms with coefficients εα and ε, where 0 < ε « 1 and α > 0 is a fixed parameter. Therefore for α ≠ 1 u and z have different relaxation rates. We address the vanishing-viscosity analysis as ε ↓ 0 of the viscous system. We prove that, up to a subsequence, (reparameterized) viscous solutions converge to a parameterized curve yielding a Balanced Viscosity solution to the original rate-independent system, and providing an accurate description of the system behavior at jumps. We also give a reformulation of the notion of Balanced Viscosity solution in terms of a system of subdifferential inclusions, showing that the viscosity in u and the one in z are involved in the jump dynamics in different ways, according to whether α > 1, α =1, and α є (0,1).

  11. Efficacy of a topical bovine-derived thrombin solution as a hemostatic agent in a rodent model of hepatic injury

    PubMed Central

    Rosselli, Desiree D.; Brainard, Benjamin M.; Schmiedt, Chad W.

    2015-01-01

    Hemorrhage is a major concern in patients undergoing hepatic surgery or in those with hepatic trauma. In these cases, employing traditional hemostatic strategies can be problematic due to the diffuse nature of hepatic hemorrhage and limited opportunities for direct hemostasis. This study assessed the efficacy of a bovine-derived thrombin solution, (BT), as a topical liquid agent to augment hemostasis and survival following severe hepatic hemorrhage in a rat model. Heart rate (HR), arterial blood pressure (ABP), packed cell volume (PCV), and overall survival were evaluated in 54 rats randomly assigned to receive topical application of BT, saline, or suture ligation applied immediately to a liver lobe following controlled laceration. Six additional rats received liver laceration with no applied treatment. Intravenous fluid resuscitation was initiated and HR and ABP were recorded for 60 min, after which survivors were recovered from anesthesia. Rats were then monitored for 72 h, after which survivors were euthanized. There was no significant difference in survival time, percentage survival, intra-operative ABP or HR, or post-operative PCV between treatment groups. There is insufficient evidence to recommend BT as the sole therapy using this delivery method for mitigating severe hemorrhage from liver injury. PMID:26424911

  12. Efficacy of a topical bovine-derived thrombin solution as a hemostatic agent in a rodent model of hepatic injury.

    PubMed

    Rosselli, Desiree D; Brainard, Benjamin M; Schmiedt, Chad W

    2015-10-01

    Hemorrhage is a major concern in patients undergoing hepatic surgery or in those with hepatic trauma. In these cases, employing traditional hemostatic strategies can be problematic due to the diffuse nature of hepatic hemorrhage and limited opportunities for direct hemostasis. This study assessed the efficacy of a bovine-derived thrombin solution, (BT), as a topical liquid agent to augment hemostasis and survival following severe hepatic hemorrhage in a rat model. Heart rate (HR), arterial blood pressure (ABP), packed cell volume (PCV), and overall survival were evaluated in 54 rats randomly assigned to receive topical application of BT, saline, or suture ligation applied immediately to a liver lobe following controlled laceration. Six additional rats received liver laceration with no applied treatment. Intravenous fluid resuscitation was initiated and HR and ABP were recorded for 60 min, after which survivors were recovered from anesthesia. Rats were then monitored for 72 h, after which survivors were euthanized. There was no significant difference in survival time, percentage survival, intra-operative ABP or HR, or post-operative PCV between treatment groups. There is insufficient evidence to recommend BT as the sole therapy using this delivery method for mitigating severe hemorrhage from liver injury.

  13. Surface modification of pyrophyllite with amino silane coupling agent for the removal of 4-nitrophenol from aqueous solutions.

    PubMed

    Sayilkan, H; Erdemoğlu, S; Sener, S; Sayilkan, F; Akarsu, M; Erdemoğlu, M

    2004-07-15

    The surface of naturally hydrophobic mineral pyrophyllite was modified to hydrophilic by treatment with prehydrolyzed N-(2-aminoethyl)-3-aminopropyltrimethoxysilane (APEO) coupling agent to prepare a novel and effective adsorbent for the removal of 4-nitrophenol (4-NP) from aqueous solutions. XRD, FTIR, and SEM analyses were used to characterize the surface modification. It was found that after the grafting procedure, heat treatment at 110 degrees C results in condensation reaction between the OH groups of the APEO molecule and the hydroxyl groups and/or oxygen atoms on the pyrophyllite surface and the adsorption of 4-NP by APEO-modified pyrophyllite involves interactions between dissociated 4-NP molecules and protonated amine groups of APEO molecules attached to the mineral surface. Adsorption equilibrium data for 4-NP adsorption on APEO-treated and untreated pyrophyllite were most satisfactorily fitted using the Freundlich adsorption isotherm and adsorption capacity was found to be 0.268 mg/g for modified pyrophyllite whereas it was only 0.105 mg/g for untreated pyrophyllite. Copyright 2004 Elsevier Inc.

  14. Method of using a lignosulfonate/carbohydrate system as a sacrificial agent for surfactant flooding

    SciTech Connect

    Kalfoglou, G.

    1986-12-09

    A method is described of recovering hydrocarbons from a subterranean hydrocarbon formation which is penetrated by at least one injection well and at least one production well wherein chemicals are injected into the formation to sweep oil through the formation to at least one production well. The method consists of: injecting into the formation a solution containing about 0.1% to about 10% by weight of a mixture of at least two sacrificial agents designed to prevent the loss to the formation of the injected chemicals, the mixture of at least two sacrificial agents comprised of one sacrificial agent which is a lignosulfonate and a second sacrificial agent selected from the group consisting of alkoxylated starch, esterified starch, oxidized starch, phosphated starch, alkoxylated cellulose, carboxyalkyl cellulose, carboxyalkylakoxylated cellulose, alkylakoxylated cellulose, cellulose sulfates, and cellulose acetate sulfates.

  15. Research and Development for an Operational Information Ecology: The User-System Interface Agent Project

    NASA Technical Reports Server (NTRS)

    Srivastava, Sadanand; deLamadrid, James

    1998-01-01

    The User System Interface Agent (USIA) is a special type of software agent which acts as the "middle man" between a human user and an information processing environment. USIA consists of a group of cooperating agents which are responsible for assisting users in obtaining information processing services intuitively and efficiently. Some of the main features of USIA include: (1) multiple interaction modes and (2) user-specific and stereotype modeling and adaptation. This prototype system provides us with a development platform towards the realization of an operational information ecology. In the first phase of this project we focus on the design and implementation of prototype system of the User-System Interface Agent (USIA). The second face of USIA allows user interaction via a restricted query language as well as through a taxonomy of windows. In third phase the USIA system architecture was revised.

  16. Controllability of multi-agent systems with time-delay in state and switching topology

    NASA Astrophysics Data System (ADS)

    Ji, Zhijian; Wang, Zidong; Lin, Hai; Wang, Zhen

    2010-02-01

    In this article, the controllability issue is addressed for an interconnected system of multiple agents. The network associated with the system is of the leader-follower structure with some agents taking leader role and others being followers interconnected via the neighbour-based rule. Sufficient conditions are derived for the controllability of multi-agent systems with time-delay in state, as well as a graph-based uncontrollability topology structure is revealed. Both single and double integrator dynamics are considered. For switching topology, two algebraic necessary and sufficient conditions are derived for the controllability of multi-agent systems. Several examples are also presented to illustrate how to control the system to shape into the desired configurations.

  17. A Demand-Driven Approach for a Multi-Agent System in Supply Chain Management

    NASA Astrophysics Data System (ADS)

    Kovalchuk, Yevgeniya; Fasli, Maria

    This paper presents the architecture of a multi-agent decision support system for Supply Chain Management (SCM) which has been designed to compete in the TAC SCM game. The behaviour of the system is demand-driven and the agents plan, predict, and react dynamically to changes in the market. The main strength of the system lies in the ability of the Demand agent to predict customer winning bid prices - the highest prices the agent can offer customers and still obtain their orders. This paper investigates the effect of the ability to predict customer order prices on the overall performance of the system. Four strategies are proposed and compared for predicting such prices. The experimental results reveal which strategies are better and show that there is a correlation between the accuracy of the models' predictions and the overall system performance: the more accurate the prediction of customer order prices, the higher the profit.

  18. Distributed containment control of heterogeneous fractional-order multi-agent systems with communication delays

    NASA Astrophysics Data System (ADS)

    Yang, Hongyong; Han, Fujun; Zhao, Mei; Zhang, Shuning; Yue, Jun

    2017-08-01

    Because many networked systems can only be characterized with fractional-order dynamics in complex environments, fractional-order calculus has been studied deeply recently. When diverse individual features are shown in different agents of networked systems, heterogeneous fractional-order dynamics will be used to describe the complex systems. Based on the distinguishing properties of agents, heterogeneous fractional-order multi-agent systems (FOMAS) are presented. With the supposition of multiple leader agents in FOMAS, distributed containment control of FOMAS is studied in directed weighted topologies. By applying Laplace transformation and frequency domain theory of the fractional-order operator, an upper bound of delays is obtained to ensure containment consensus of delayed heterogenous FOMAS. Consensus results of delayed FOMAS in this paper can be extended to systems with integer-order models. Finally, numerical examples are used to verify our results.

  19. Cooperation in Human-Agent Systems to Support Resilience: A Microworld Experiment.

    PubMed

    Chiou, Erin K; Lee, John D

    2016-09-01

    This study uses a dyadic approach to understand human-agent cooperation and system resilience. Increasingly capable technology fundamentally changes human-machine relationships. Rather than reliance on or compliance with more or less reliable automation, we investigate interaction strategies with more or less cooperative agents. A joint-task microworld scenario was developed to explore the effects of agent cooperation on participant cooperation and system resilience. To assess the effects of agent cooperation on participant cooperation, 36 people coordinated with a more or less cooperative agent by requesting resources and responding to requests for resources in a dynamic task environment. Another 36 people were recruited to assess effects following a perturbation in their own hospital. Experiment 1 shows people reciprocated the cooperative behaviors of the agents; a low-cooperation agent led to less effective interactions and less resource sharing, whereas a high-cooperation agent led to more effective interactions and greater resource sharing. Experiment 2 shows that an initial fast-tempo perturbation undermined proactive cooperation-people tended to not request resources. However, the initial fast tempo had little effect on reactive cooperation-people tended to accept resource requests according to cooperation level. This study complements the supervisory control perspective of human-automation interaction by considering interdependence and cooperation rather than the more common focus on reliability and reliance. The cooperativeness of automated agents can influence the cooperativeness of human agents. Design and evaluation for resilience in teams involving increasingly autonomous agents should consider the cooperative behaviors of these agents. © 2016, Human Factors and Ergonomics Society.

  20. A multi-agent approach for a self-reconfigurable electric power distribution system

    NASA Astrophysics Data System (ADS)

    Gómez–Gualdrón, Janeth G.; Vélez-Reyes, Miguel

    2006-05-01

    Electric power distribution systems can be found almost everywhere, from ship power systems to data centers. In many critical applications, there is needed to maintain minimal operating capability under fault conditions. To carry out this goal it is necessary to develop energy distribution control techniques, which let implement a self-reconfigurable energy distribution system. This research project is looking at the implementation of multi-agent systems to develop a self-reconfigurable electric power distribution system. A prototype of a Multi-Agent system is proposed to reconfigure the system in order to maximize the number of served loads with highest priority. The shipboard power system is simulated in Matlab TM Simulink TM and the Multi-Agent System is implemented using Java programming language and JADE platform.

  1. Segregation of solutes and gases in experimental freezing of dilute solutions: implications for natural glacial systems

    NASA Astrophysics Data System (ADS)

    Killawee, J. A.; Fairchild, I. J.; Tison, J.-L.; Janssens, L.; Lorrain, R.

    1998-12-01

    Low ionic strength waters containing significant calcium and bicarbonate are common in nature, but little literature exists on their behaviour during freezing. Modelling indicates that freezing-induced concentration of solutes (in a closed-system) would lead to progressive increase in calcite saturation index, despite rising partial pressure of CO 2 (PCO 2), but the consequences of CaCO 3 precipitation for the distribution of matter between solid, liquid, and gas phases required experimental investigation. We studied the effects of variations in the rate of advance of an ice-water interface and in the initial degree of saturation for calcite on the behaviour of the system. Downward growth of ice in a 24-cm diameter cylindrical vessel was achieved at a constant linear rate of 3 or 8 mm/h by the progressive cooling of an overlying alcohol reservoir, and the expansion of volume accommodated by regular water sampling through side ports, together with a small expansion chamber. Initial air-saturated solutions (initial PCO 2 in the range 10 -3 to 10 -3.2) were prepared to reflect a range from strongly undersaturated to supersaturated for calcite. Comparative blank experiments were run using deionized water. Ice growth led to enrichment in solutes at the ice-water interface and the creation of a diffusive boundary layer, calculated to be 0.6 mm thick, truncated below by convecting fluid. The first-formed ice (stage 1), was relatively solute-rich because of initial rapid ice nucleation. Where solutions were not strongly supersaturated for calcite this was followed by formation of a solute-poor (stage 2) ice. Ice-interface water segregation coefficients of stage 2 ice were calculated to be 0.0004-0.003 for various solute ions. The relative magnitude of segregation coefficients (Mg 2+ > Ca 2+ > Sr 2+) is attributed to interstitial incorporation (coupled with HCO 3-) in the ice lattice, and controlled by ion size. Air bubbles nucleated once nitrogen supersaturation had

  2. Self limiting features of accidental criticality in a solution system

    SciTech Connect

    Malenfant, R.E.

    1988-01-01

    Experience with the SHEBA solution critical assembly during validation testing of accidental criticality alarm detectors provided several insights into the character of potential accidental excursions. Two observations were of particular interest. First, it is nearly impossible to maintain a solution system, particularly one employing low-enrichment material, in a constant state. If super-critical, the system will heat up, expand (or form bubbles), return to a sub-critical state, and shut down of its own accord without going into short period oscillations. Second, a very slow change in the system could produce a long ''pulse'' resulting in lengthy exposures, a high dose, but a low dose rate. The experiments dramatically contradicted the popular contention that accidental criticality is characterized by a blue flash, a clap of thunder, and violet expulsion of material. 5 refs., 3 figs., 4 tabs.

  3. Discontinuous solutions to hyperbolic systems under operator splitting

    NASA Technical Reports Server (NTRS)

    Roe, P. L.

    1987-01-01

    Two-dimensional systems of linear hyperbolic equations are studied with regard to their behavior under a solution strategy that in alternate time-steps solves exactly the component one-dimensional operators. The initial data is a step function across an oblique discontinuity. The manner in which this discontinuity breaks up under repeated applications of the split operator is analyzed, and it is shown that the split solution will fail to match the true solution in any case where the two operators do not share all their eigenvectors. The special case of the fluid flow equations is analyzed in more detail, and it is shown that arbitrary initial data gives rise to pseudo acoustic waves and a non-physical stationary wave. The implications of these findings for the design of high-resolution computing schemes are discussed.

  4. Bifurcations from nondegenerate families of periodic solutions in Lipschitz systems

    NASA Astrophysics Data System (ADS)

    Buică, Adriana; Llibre, Jaume; Makarenkov, Oleg

    The paper addresses the problem of bifurcation of periodic solutions from a normally nondegenerate family of periodic solutions of ordinary differential equations under perturbations. The approach to solve this problem can be described as transforming (by a Lyapunov-Schmidt reduction) the initial system into one which is in the standard form of averaging, and subsequently applying the averaging principle. This approach encounters a fundamental problem when the perturbation is only Lipschitz (nonsmooth) as we do not longer have smooth Lyapunov-Schmidt projectors. The situation of Lipschitz perturbations has been addressed in the literature lately and the results obtained conclude the existence of the bifurcated branch of periodic solutions. Motivated by recent challenges in control theory, we are interested in the uniqueness problem. We achieve this in the case when the Lipschitz constant of the perturbation obeys a suitable estimate.

  5. Endogenous Price Bubbles in a Multi-Agent System of the Housing Market

    PubMed Central

    2015-01-01

    Economic history shows a large number of boom-bust cycles, with the U.S. real estate market as one of the latest examples. Classical economic models have not been able to provide a full explanation for this type of market dynamics. Therefore, we analyze home prices in the U.S. using an alternative approach, a multi-agent complex system. Instead of the classical assumptions of agent rationality and market efficiency, agents in the model are heterogeneous, adaptive, and boundedly rational. We estimate the multi-agent system with historical house prices for the U.S. market. The model fits the data well and a deterministic version of the model can endogenously produce boom-and-bust cycles on the basis of the estimated coefficients. This implies that trading between agents themselves can create major price swings in absence of fundamental news. PMID:26107740

  6. Resilient distributed control in the presence of misbehaving agents in networked control systems.

    PubMed

    Zeng, Wente; Chow, Mo-Yuen

    2014-11-01

    In this paper, we study the problem of reaching a consensus among all the agents in the networked control systems (NCS) in the presence of misbehaving agents. A reputation-based resilient distributed control algorithm is first proposed for the leader-follower consensus network. The proposed algorithm embeds a resilience mechanism that includes four phases (detection, mitigation, identification, and update), into the control process in a distributed manner. At each phase, every agent only uses local and one-hop neighbors' information to identify and isolate the misbehaving agents, and even compensate their effect on the system. We then extend the proposed algorithm to the leaderless consensus network by introducing and adding two recovery schemes (rollback and excitation recovery) into the current framework to guarantee the accurate convergence of the well-behaving agents in NCS. The effectiveness of the proposed method is demonstrated through case studies in multirobot formation control and wireless sensor networks.

  7. Endogenous Price Bubbles in a Multi-Agent System of the Housing Market.

    PubMed

    Kouwenberg, Roy; Zwinkels, Remco C J

    2015-01-01

    Economic history shows a large number of boom-bust cycles, with the U.S. real estate market as one of the latest examples. Classical economic models have not been able to provide a full explanation for this type of market dynamics. Therefore, we analyze home prices in the U.S. using an alternative approach, a multi-agent complex system. Instead of the classical assumptions of agent rationality and market efficiency, agents in the model are heterogeneous, adaptive, and boundedly rational. We estimate the multi-agent system with historical house prices for the U.S. market. The model fits the data well and a deterministic version of the model can endogenously produce boom-and-bust cycles on the basis of the estimated coefficients. This implies that trading between agents themselves can create major price swings in absence of fundamental news.

  8. [Microorganism test systems and antibiograms useful for the proper use of antibacterial agents].

    PubMed

    Takahashi, Shunji

    2010-07-01

    Antimicrobial agents are used for the accurate diagnosis of infectious diseases and effective implementation of antibacterial chemotherapy. The role of microbiological technologists is to provide data from microorganism tests useful for rapid infection treatment. Gram strain can be used to observe microorganisms and neutrophils from specimens of a patient. It is also possible to estimate the kinds of microorganism. If bacterial infectious disease is negative, there is no need for antibacterial chemotherapy. The applied dose of antibacterial agents is different in every hospital. Also, there is a difference in the percentage antibacterial agent susceptibility of isolates. Antibiograms must be created to investigate local factors. For empiric therapy, antibiograms are useful when choosing antibacterial agents showing marked efficacy against the clinical isolate. Microorganism test systems which are useful for the proper use of antibacterial agents are necessary to facilitate safe antibacterial chemotherapy and prevent the development of resistant bacteria. We report a microorganism test system employed at the Sapporo City General Hospital.

  9. Shortcuts in complex engineering systems: a principal-agent approach to risk management.

    PubMed

    Garber, Russ; Paté-Cornell, Elisabeth

    2012-05-01

    In this article, we examine the effects of shortcuts in the development of engineered systems through a principal-agent model. We find that occurrences of illicit shortcuts are closely related to the incentive structure and to the level of effort that the agent is willing to expend from the beginning of the project to remain on schedule. Using a probabilistic risk analysis to determine the risks of system failure from these shortcuts, we show how a principal can choose optimal settings (payments, penalties, and inspections) that can deter an agent from cutting corners and maximize the principal's value through increased agent effort. We analyze the problem for an agent with limited liability. We consider first the case where he is risk neutral; we then include the case where he is risk averse. © 2011 Society for Risk Analysis.

  10. Multi-agent system for line detection on images

    NASA Astrophysics Data System (ADS)

    Alpatov, Boris A.; Babayan, Pavel V.; Shubin, Nikita Yu.

    2016-10-01

    Lines are one of the most informative structure elements on any images. For this reason, objects detection and recognition problems are often reduced to edge detection task. One of the most popular approaches to detect lines is based on the Hough transform or Radon transform. However, using both of transforms allows estimating the infinite lines parameters only. It is necessary to use additional approaches to estimate the ends of the detected lines. Moreover, Radon transform does not allow detecting non-straight curve shapes at all. This work is oriented to solve line detection problem using Radon transform and multi-agent approach. The results of the experimental researches that confirm the effectiveness of the proposed approach are given. The real full HD image sequences are used. The direction of further improvements is proposed.

  11. Contingency theoretic methodology for agent-based web-oriented manufacturing systems

    NASA Astrophysics Data System (ADS)

    Durrett, John R.; Burnell, Lisa J.; Priest, John W.

    2000-12-01

    The development of distributed, agent-based, web-oriented, N-tier Information Systems (IS) must be supported by a design methodology capable of responding to the convergence of shifts in business process design, organizational structure, computing, and telecommunications infrastructures. We introduce a contingency theoretic model for the use of open, ubiquitous software infrastructure in the design of flexible organizational IS. Our basic premise is that developers should change in the way they view the software design process from a view toward the solution of a problem to one of the dynamic creation of teams of software components. We postulate that developing effective, efficient, flexible, component-based distributed software requires reconceptualizing the current development model. The basic concepts of distributed software design are merged with the environment-causes-structure relationship from contingency theory; the task-uncertainty of organizational- information-processing relationships from information processing theory; and the concept of inter-process dependencies from coordination theory. Software processes are considered as employees, groups of processes as software teams, and distributed systems as software organizations. Design techniques already used in the design of flexible business processes and well researched in the domain of the organizational sciences are presented. Guidelines that can be utilized in the creation of component-based distributed software will be discussed.

  12. Slacking in the context of agent-based assessment in virtual rehabilitation systems.

    PubMed

    Coffey, Aodhán L; Ward, Tomás E

    2014-01-01

    Efforts are already underway to develop technology-derived solutions which automate aspects of conventional therapy. Ideally we would like to develop a human-like virtual therapist, in an attempt to enhance automated rehabilitation particularly in the home setting. One interesting skill of the experienced human therapist that we would like to model is the ability to recognize and manage behavior patterns known to decrease the effectiveness of rehabilitation. A particularly compelling example of such behavior is described in the context of robot-assisted therapy, where it has been demonstrated that "assist-as-needed" strategies may impact negatively on rehabilitation outcomes due to an intrinsic property of the human motor systems that encourages "slacking" as a form of energy optimization. In this work we endeavor to explore and extend this concept by giving it context in the standard therapist-patient interaction setting. We developed an apparatus which can measure and quantify grip strength and an agent based virtual therapist that can assess performance and offer simple natural language feedback in real time. We then conducted a series of experiments with healthy subjects in which the mapping between performance and feedback valence is altered. Our results demonstrate that subject performance is dependent on the feedback rules and that in particular, excessively positive feedback yields performance dynamics analogous to those observed in slacking studies. These preliminary results have implications for the design of virtual therapist systems.

  13. Output Containment Control of Linear Heterogeneous Multi-Agent Systems Using Internal Model Principle.

    PubMed

    Zuo, Shan; Song, Yongduan; Lewis, Frank L; Davoudi, Ali

    2017-01-04

    This paper studies the output containment control of linear heterogeneous multi-agent systems, where the system dynamics and even the state dimensions can generally be different. Since the states can have different dimensions, standard results from state containment control do not apply. Therefore, the control objective is to guarantee the convergence of the output of each follower to the dynamic convex hull spanned by the outputs of leaders. This can be achieved by making certain output containment errors go to zero asymptotically. Based on this formulation, two different control protocols, namely, full-state feedback and static output-feedback, are designed based on internal model principles. Sufficient local conditions for the existence of the proposed control protocols are developed in terms of stabilizing the local followers' dynamics and satisfying a certain H∞ criterion. Unified design procedures to solve the proposed two control protocols are presented by formulation and solution of certain local state-feedback and static output-feedback problems, respectively. Numerical simulations are given to validate the proposed control protocols.

  14. Autonomous Agents: The Origins and Co-Evolution of Reproducing Molecular Systems

    NASA Technical Reports Server (NTRS)

    Kauffman, Stuart

    1999-01-01

    The central aim of this award concerned an investigation into, and adequate formulation of, the concept of an "autonomous agent." If we consider a bacterium swimming upstream in a glucose gradient, we are willing to say of the bacterium that it is going to get food. That is, we are willing, and do, describe the bacterium as acting on its own behalf in an environment. All free living cells are, in this sense, autonomous agents. But the bacterium is "just" a set of molecules. We define an autonomous agent as a physical system able to act on its own behalf in an environment, then ask, "What must a physical system be to be an autonomous agent?" The tentative definition for a molecular autonomous agent is that it must be self-reproducing and carry out at least one thermodynamic work cycle. The work carried out in this grant involved, among other features, the development of a detailed model of a molecular autonomous agent, and study of the kinetics of this system. In particular, a molecular autonomous agent must, by the above tentative definition, not only reproduce, but must carry out at least one work cycle. I took, as a simple example of a self-reproducing molecular system, the single-stranded DNA hexamer 3'CCGCGG5' which can line up and ligate its two complementary trimers, 5'CCG3' and 5'CGG3'. But the two ligated trimers constitute the same molecular sequence in the 3' to 5' direction as the initial hexamer, hence this system is autocatalytic. On the other hand the above system is not yet an autonomous agent. At the minimum, autonomous agents, as I have defined them, are a new class of chemical reaction network. At a maximum, they may constitute a proper definition of life itself.

  15. A Multifaceted Medical Data Information System and One Product: The Index-Handbook of Ototoxic Agents

    ERIC Educational Resources Information Center

    Heath, Miriam T.; Lunin, Lois F.

    1976-01-01

    Describes the creation and development of a biomedical information system that includes a machine-readable data base containing clinical and research data and a publication entitled the Index-Handbook of Ototoxic Agents. (Author)

  16. Controllability of heterogeneous multi-agent systems under directed and weighted topology

    NASA Astrophysics Data System (ADS)

    Guan, Yongqiang; Ji, Zhijian; Zhang, Lin; Wang, Long

    2016-05-01

    This paper considers the controllability problem for both continuous- and discrete-time linear heterogeneous multi-agent systems with directed and weighted communication topology. First, two kinds of neighbour-based control protocols based on the distributed protocol of first-order and second-order multi-agent systems are proposed, under which it is shown that a heterogeneous multi-agent system is controllable if the underlying communication topology is controllable. Then, under special leader selection, the result shows that the controllability of a heterogeneous multi-agent system is solely decided by its communication topology graph. Furthermore, some necessary and/or sufficient conditions are derived for controllability of communication topology from algebraic and graphical perspectives. Finally, simulation examples are presented to demonstrate the effectiveness of the theoretical results.

  17. Pattern-oriented modeling of agent-based complex systems: Lessons from ecology

    USGS Publications Warehouse

    Grimm, Volker; Revilla, Eloy; Berger, Uta; Jeltsch, Florian; Mooij, Wolf M.; Railsback, Steven F.; Thulke, Hans-Hermann; Weiner, Jacob; Wiegand, Thorsten; DeAngelis, Donald L.

    2005-01-01

    Agent-based complex systems are dynamic networks of many interacting agents; examples include ecosystems, financial markets, and cities. The search for general principles underlying the internal organization of such systems often uses bottom-up simulation models such as cellular automata and agent-based models. No general framework for designing, testing, and analyzing bottom-up models has yet been established, but recent advances in ecological modeling have come together in a general strategy we call pattern-oriented modeling. This strategy provides a unifying framework for decoding the internal organization of agent-based complex systems and may lead toward unifying algorithmic theories of the relation between adaptive behavior and system complexity.

  18. A Multifaceted Medical Data Information System and One Product: The Index-Handbook of Ototoxic Agents

    ERIC Educational Resources Information Center

    Heath, Miriam T.; Lunin, Lois F.

    1976-01-01

    Describes the creation and development of a biomedical information system that includes a machine-readable data base containing clinical and research data and a publication entitled the Index-Handbook of Ototoxic Agents. (Author)

  19. TOXICITY-BASED CHEMICAL AGENT DETECTION SYSTEMS: CONTINUOUS MONITOR AND EXPOSURE HISTORY

    EPA Science Inventory

    This project will develop and characterize chemical agent detection systems that will provide broad toxicological screening information to first responders and building decontamination personnel. The primary goal for this technology is to detect the presence of airborne chemic...

  20. Applying AUML and UML 2 in the Multi-agent Systems Project

    NASA Astrophysics Data System (ADS)

    Guedes, Gilleanes Thorwald Araujo; Vicari, Rosa Maria

    This article discusses the viability of the AUML and UML languages employment, from the latter's version 2.0 on, in the multi-agent systems project. In this article some works that have used UML for the project of systems that involved agents, as well as some AOSE (Agent Oriented Software Engineering) methodologies that use in some way UML or AUML (or both), are presented. Immediately afterwards the article approaches the AUML language, highlighting the innovations proposed by same and how it can be applied to the multi-agent systems project, identifying its advantages and disadvantages. After that, the paper passes on to describe how UML, from its version 2.0 on, has bypassed AUML and how the former can be applied to the multiagent systems project, pinpointing its positive aspects and its deficiencies.

  1. TOXICITY-BASED CHEMICAL AGENT DETECTION SYSTEMS: CONTINUOUS MONITOR AND EXPOSURE HISTORY

    EPA Science Inventory

    This project will develop and characterize chemical agent detection systems that will provide broad toxicological screening information to first responders and building decontamination personnel. The primary goal for this technology is to detect the presence of airborne chemic...

  2. Distributed event-triggered output regulation of multi-agent systems

    NASA Astrophysics Data System (ADS)

    Wang, Xiaoli; Ni, Wei; Ma, Zhibin

    2015-03-01

    Motivated by the future use of embedded microprocessors with limited resources and limited computational resources, the distributed output regulation with event-driven strategies problem of linear multi-agent systems is considered in this paper. The main task is to design distributed feedback by employing event-triggered technique for multi-agent systems such that all agents can track an active leader, and/or distributed disturbance rejection. Both leader and disturbance are generated by some external system (exosystem). Both distributed static and dynamic feedback with event-triggered strategy are constructed here. Then, the input-to-state stability of the closed-loop multi-agent system is analysed. Finally, a numerical example is given to validate the proposed control.

  3. Pattern-oriented modeling of agent-based complex systems: lessons from ecology.

    PubMed

    Grimm, Volker; Revilla, Eloy; Berger, Uta; Jeltsch, Florian; Mooij, Wolf M; Railsback, Steven F; Thulke, Hans-Hermann; Weiner, Jacob; Wiegand, Thorsten; DeAngelis, Donald L

    2005-11-11

    Agent-based complex systems are dynamic networks of many interacting agents; examples include ecosystems, financial markets, and cities. The search for general principles underlying the internal organization of such systems often uses bottom-up simulation models such as cellular automata and agent-based models. No general framework for designing, testing, and analyzing bottom-up models has yet been established, but recent advances in ecological modeling have come together in a general strategy we call pattern-oriented modeling. This strategy provides a unifying framework for decoding the internal organization of agent-based complex systems and may lead toward unifying algorithmic theories of the relation between adaptive behavior and system complexity.

  4. Selection of an averaging technique by simulation study of a DIAL system for toxic agents monitoring

    NASA Astrophysics Data System (ADS)

    Dudeja, Jai Paul; Jindal, Mukesh Kumar; Veerabuthiran, S.

    2007-10-01

    Differential Absorption Lidar (DIAL) is a very effective technique for standoff detection of various toxic agents in the atmosphere. The Lidar backscattered signal received usually has poor signal to noise (SNR) ratio. In order to improve the SNR, statistical averaging over a number of laser pulses is employed. The aim of the present work is to select a particular statistical averaging technique, which is most suitable in removing the noise in Lidar return signals. The DIAL system considered here uses laser transmitters based on OPO based (2-5 μm) and TEA CO2 (9-11μm) lasers. Eight commonly used chemical warfare agents including five nerve agents and three blister agents have been considered here as examples of toxic agents. A Graphical User Interface (GUI) software has been developed in LabVIEW to simulate return signals mixed with the expected noise levels. A toxic agent cloud with a given thickness and concentration has been assumed to be detected in the ambient atmospheric conditions at various ranges up to 5 Km. Data for 200 pulses per agent was stored in the computer memory. Various known statistical averaging techniques were used and number concentrations of particular agent have been computed and compared with ideal Lidar return signal values. This exercise was repeated for all the eight agents and based on the results obtained; the most suitable averaging technique has been selected.

  5. Integrated control of lateral and vertical vehicle dynamics based on multi-agent system

    NASA Astrophysics Data System (ADS)

    Huang, Chen; Chen, Long; Yun, Chaochun; Jiang, Haobin; Chen, Yuexia

    2014-03-01

    The existing research of the integrated chassis control mainly focuses on the different evaluation indexes and control strategy. Among the different evaluation indexes, the comprehensive properties are usually not considered based on the non-linear superposition principle. But, the control strategy has some shortages on tyre model with side-slip angle, road adhesion coefficient, vertical load and velocity. In this paper, based on belief, desire and intention(BDI)-agent model framework, the TYRE agent, electric power steering(EPS) agent and active suspension system(ASS) agent are proposed. In the system(SYS) agent, the coordination mechanism is employed to manage interdependences and conflicts among other agents, so as to improve the flexibility, adaptability, and robustness of the global control system. Due to the existence of the simulation demand of dynamic performance, the vehicle multi-body dynamics model is established by SIMPACK. And then the co-simulation analysis is conducted to evaluate the proposed multi-agent system(MAS) controller. The simulation results demonstrate that the MAS has good effect on the performance of EPS and ASS. Meantime, the better road feeling for the driver is provided considering the multiple and complex driving traffic. Finally, the MAS rapid control prototyping is built to conduct the real vehicle test. The test results are consistent to the simulation results, which verifies the correctness of simulation. The proposed research ensures the driving safety, enhances the handling stability, and improves the ride comfort.

  6. Formal Modeling of Multi-Agent Systems using the Pi-Calculus and Epistemic Logic

    NASA Technical Reports Server (NTRS)

    Rorie, Toinette; Esterline, Albert

    1998-01-01

    Multi-agent systems have become important recently in computer science, especially in artificial intelligence (AI). We allow a broad sense of agent, but require at least that an agent has some measure of autonomy and interacts with other agents via some kind of agent communication language. We are concerned in this paper with formal modeling of multi-agent systems, with emphasis on communication. We propose for this purpose to use the pi-calculus, an extension of the process algebra CCS. Although the literature on the pi-calculus refers to agents, the term is used there in the sense of a process in general. It is our contention, however, that viewing agents in the AI sense as agents in the pi-calculus sense affords significant formal insight. One formalism that has been applied to agents in the AI sense is epistemic logic, the logic of knowledge. The success of epistemic logic in computer science in general has come in large part from its ability to handle concepts of knowledge that apply to groups. We maintain that the pi-calculus affords a natural yet rigorous means by which groups that are significant to epistemic logic may be identified, encapsulated, structured into hierarchies, and restructured in a principled way. This paper is organized as follows: Section 2 introduces the pi-calculus; Section 3 takes a scenario from the classical paper on agent-oriented programming [Sh93] and translates it into a very simple subset of the n-calculus; Section 4 then shows how more sophisticated features of the pi-calculus may bc brought into play; Section 5 discusses how the pi-calculus may be used to define groups for epistemic logic; and Section 6 is the conclusion.

  7. Formal Modeling of Multi-Agent Systems using the Pi-Calculus and Epistemic Logic

    NASA Technical Reports Server (NTRS)

    Rorie, Toinette; Esterline, Albert

    1998-01-01

    Multi-agent systems have become important recently in computer science, especially in artificial intelligence (AI). We allow a broad sense of agent, but require at least that an agent has some measure of autonomy and interacts with other agents via some kind of agent communication language. We are concerned in this paper with formal modeling of multi-agent systems, with emphasis on communication. We propose for this purpose to use the pi-calculus, an extension of the process algebra CCS. Although the literature on the pi-calculus refers to agents, the term is used there in the sense of a process in general. It is our contention, however, that viewing agents in the AI sense as agents in the pi-calculus sense affords significant formal insight. One formalism that has been applied to agents in the AI sense is epistemic logic, the logic of knowledge. The success of epistemic logic in computer science in general has come in large part from its ability to handle concepts of knowledge that apply to groups. We maintain that the pi-calculus affords a natural yet rigorous means by which groups that are significant to epistemic logic may be identified, encapsulated, structured into hierarchies, and restructured in a principled way. This paper is organized as follows: Section 2 introduces the pi-calculus; Section 3 takes a scenario from the classical paper on agent-oriented programming [Sh93] and translates it into a very simple subset of the n-calculus; Section 4 then shows how more sophisticated features of the pi-calculus may bc brought into play; Section 5 discusses how the pi-calculus may be used to define groups for epistemic logic; and Section 6 is the conclusion.

  8. Distributed heterogeneous inspecting system and its middleware-based solution.

    PubMed

    Huang, Li-can; Wu, Zhao-hui; Pan, Yun-he

    2003-01-01

    There are many cases when an organization needs to monitor the data and operations of its supervised departments, especially those departments which are not owned by this organization and are managed by their own information systems. Distributed Heterogeneous Inspecting System (DHIS) is the system an organization uses to monitor its supervised departments by inspecting their information systems. In DHIS, the inspected systems are generally distributed, heterogeneous, and constructed by different companies. DHIS has three key processes-abstracting core data sets and core operation sets, collecting these sets, and inspecting these collected sets. In this paper, we present the concept and mathematical definition of DHIS, a metadata method for solving the interoperability, a security strategy for data transferring, and a middleware-based solution of DHIS. We also describe an example of the inspecting system at WENZHOU custom.

  9. Distributed structural health monitoring system based on smart wireless sensor and multi-agent technology

    NASA Astrophysics Data System (ADS)

    Yuan, Shenfang; Lai, Xiaosong; Zhao, Xia; Xu, Xin; Zhang, Liang

    2006-02-01

    This paper presents a new parallel distributed structural health monitoring technology based on the wireless sensor network and multi-agent system for large scale engineering structures. The basic idea of this new technology is that of adopting the smart wireless sensor with on-board microprocessor to form the monitoring sensor network and the multi-agent technology to manage the whole health monitoring system. Using this technology, the health monitoring system becomes a distributing parallel system instead of a serial system with all processing work done by the central computer. The functions, the reliability, the flexibility and the speed of the whole system will be greatly improved. In addition, with wireless communication links instead of wires, the system weight and complexity will be lowered. In this paper, the distributed smart wireless sensor network is designed first based on the Berkeley Mote Mica wireless sensor platform. Two kinds of sensor have been adopted: piezoelectric sensors and electric resistance wires. They are connected to a Mica MPR board though a designed charge amplifier circuit or bridge circuit and MTS101 board. Seven kinds of agents are defined for the structural health monitoring system. A distributed health monitoring architecture based on the defined agents is proposed. Finally, a composite structural health monitoring system based on a Mica wireless platform and multi-agent technology is developed to evaluate the efficacy of the new technology. The developed system can successfully monitor the concentrated load position or a loose bolt position.

  10. The influence of surface modification, coating agents and pH value of aqueous solutions on physical properties of magnetite nanoparticles investigated by ESR method

    NASA Astrophysics Data System (ADS)

    Dobosz, Bernadeta; Krzyminiewski, Ryszard; Kurczewska, Joanna; Schroeder, Grzegorz

    2017-05-01

    The article presents the results of electron spin resonance (ESR) studies for aqueous solutions of functionalized superparamagnetic iron(II,III) oxide nanoparticles. The samples studied differed in type of organic ligands at the magnetite surface, type of coating agent and pH value of aqueous solutions. The ESR spectra of the samples were obtained at room temperature and at 230 K. The field cooling (FC) experiment was performed for selected samples, and the effective anisotropy field (HK2) and the first order magnetocrystalline anisotropy constant (K1) was calculated. The process of the nanoparticles diffusion in different environments (human blood, human serum) forced by an inhomogeneous magnetic field was monitored and their interactions with different solvents have been discussed. It has been shown that ESR method is useful to observe the impact of organic ligands at the magnetite surface, type of coating agent and pH value of aqueous solutions on the properties of iron(II,III) oxide nanoparticles.

  11. The Felin soldier system: a tailored solution for networked operations

    NASA Astrophysics Data System (ADS)

    Le Sueur, Philippe

    2007-04-01

    Sagem Defense Securite has been awarded a 800M euro contract for the French infantrymen modernisation programme. This programme covers the development, the qualification and the production of about 32 000 soldier systems to equip all the French infantry starting fielding in 2008. The FELIN soldier system provides the infantryman with an integrated system increasing dramatically the soldier capability in any dismounted close combat domains. Man remains at the centre of the system, which can interface equipments or systems already fielded and future equipments to match any customer's needs. Urban operations are carefully addressed thanks to a versatile and modular solution and a dedicated C4I system, Sagem Defense Securite is a European leader in defence electronics and takes part of this major French Army transformation programme, which will play a key role in the Info Centric Network initiatives promoted in France and other countries. This paper summarises the system solutions selected by the French Army with a focus on the networked capabilities and the optronic devices.

  12. A Portable System for Nuclear, Chemical Agent and Explosives Identification

    SciTech Connect

    Parker, W.E.; Buckley, W.M.; Kreek, S.A.; Caffrey, A.J.; Mauger, G.J.; Lavietes, A.D.; Dougan, A.D.

    2000-09-29

    The FRIS/PINS hybrid integrates the LLNL-developed Field Radionuclide Identification System (FRIS) with the INEEL-developed Portable Isotopic Neutron Spectroscopy (PINS) chemical assay system to yield a combined general radioisotope, special nuclear material, and chemical weapons/explosives detection and identification system. The PINS system uses a neutron source and a high-purity germanium {gamma}-ray detector. The FRIS system uses an electrochemically cooled germanium detector and its own analysis software to detect and identify special nuclear material and other radioisotopes. The FRIS/PINS combined system also uses the electromechanically-cooled germanium detector. There is no other currently available integrated technology that can combine an active neutron interrogation and analysis capability for CWE with a passive radioisotope measurement and identification capability for special nuclear material.

  13. Middle infrared optoelectronic absorption systems for monitoring physiological glucose solutions

    NASA Astrophysics Data System (ADS)

    Martin, W. Blake

    Tight monitoring of the glucose levels for diabetic individuals is essential to control long-term complications. A definitive diabetes management system has yet to be developed for the diabetic. This research investigates the application of middle infrared absorption frequencies for monitoring glucose levels in biological solutions. Three frequencies were identified using a Fourier transform infrared spectrometer and correlated to changes in glucose concentrations. The 1035 +/- 1 cm-1 frequency was determined to be the best representative frequency. Other biological molecules contributed no significant interference to monitoring glucose absorption. A second frequency at 1193 cm-1 was suggested as a representative background absorption frequency, which could be used for more accurate glucose absorption values. Next, a quantum cascade laser optoelectronic absorption system was designed and developed to monitor glucose. After careful alignment and design, the system was used to monitor physiological glucose concentrations. Correlation at 1036 cm-1 with glucose changes was comparable to the previous results. The use of the background absorption frequency was verified. This frequency essentially acts as a calibrating frequency to adjust in real-time to any changes in the background absorption that may alter the accuracy of the predicted glucose value. An evanescent wave cavity ring-down spectroscopy technique was explored to monitor molecules in a biological solution. Visible light at 425 nm was used to monitor hemoglobin in control urine samples. An adsorption isotherm for hemoglobin was detectable to limit of 5.8 nM. Evanescent wave cavity ring-down spectroscopy would be useful for a glucose solution. Given an equivalent system designed for the middle infrared, the molar extinction coefficient of glucose allows for a detectable limit of 45 mg/dl for a free-floating glucose solution, which is below normal physiological concentrations. The future use of a hydrophobic

  14. Wallpaper concept solution fabrication experiences in FGD systems

    SciTech Connect

    Agarwal, D.C.; Flasche, L.H.

    1987-01-01

    In the last few years, a concentrated research effort has led to a better understanding of the corrosion problems in flue gas desulfurization (FGD) systems of coal fired power plants. At first look, operation of a typical limestone FGD system appears very simple, hence the first generation scrubbers of early to mid 70's were designers inspiration. However, the designers inspiration soon turned into a utility's nightmare due to failures of metals and non-metals, both failing in a an embarrassingly short time. A solution was needed which had to be reliable, simple, and cost effective. This objective was met via the application of wallpaper concept, which now has been very well accepted in the industry and is becoming increasingly more popular due to the many successful case histories. This paper describes the wallpaper concept solution, the fabrication techniques, the experiences at certain utilities, the precautions which need to be followed, the associated economics, and some case histories.

  15. Consensus of heterogeneous multi-agent systems with switching jointly-connected interconnection

    NASA Astrophysics Data System (ADS)

    Mo, Lipo; Niu, Yuguang; Pan, Tingting

    2015-06-01

    In this paper, the consensus problem of heterogeneous multi-agent systems with switching jointly-connected interconnection and a leader is considered. Firstly, by a model transformation, the original closed-loop system is turned into an equivalent system. And then, by applying the matrix theory and Lyapunov directed method, the convergence of the multi-agent systems is analyzed, a sufficient condition for consensus of systems is derived when the communication topologies are jointly-connected. Finally, simulation results are provided to demonstrate the effectiveness of presented results.

  16. Proceedings 3rd NASA/IEEE Workshop on Formal Approaches to Agent-Based Systems (FAABS-III)

    NASA Technical Reports Server (NTRS)

    Hinchey, Michael (Editor); Rash, James (Editor); Truszkowski, Walt (Editor); Rouff, Christopher (Editor)

    2004-01-01

    These preceedings contain 18 papers and 4 poster presentation, covering topics such as: multi-agent systems, agent-based control, formalism, norms, as well as physical and biological models of agent-based systems. Some applications presented in the proceedings include systems analysis, software engineering, computer networks and robot control.

  17. Role of glutamatergic system in nerve agent intoxication

    SciTech Connect

    Blanchet, G.; Lallement, G.; Carpentier, P.; De Groot, D.; Bodjarian, N.

    1993-05-13

    Our recent studies concerning soman-induced seizures mechanisms and subsequent brain damage are reviewed. (1) Seizure activity was associated with transient increases of extracellular concentrations of acetylcholine (ACh) and with long-lasting releases of glutamate (Glu) in all limbic areas studied. (2) Preventive intraseptal application of atropine abolished the hippocampal increases of extracellular AChi and Glu indicating a key role of septum in triggering seizure activity. (3) Early increases of hippocampal AMPA receptor binding occurred before activation of NMDA receptors. (4) Pretreatment with NBQX, an antagonist of AMPA receptor, prevented convulsions and brain damage even without atropine. In the same conditions, no protection was afforded by TCP, a non-competitive antagonist of the NMDA receptor. (5) On the contrary, in the presence of pyridostigmine and atropine, TCP blocked the seizures induced by 2 x LD50 of soman. The anticonvulsant potency of TCP was particularly obvious when administered curatively. (6) Mossy fibers sprouting takes place in the supragranular-molecular layers of rat hippocampus long after brain injury associated with abnormal neuronal excitability. (7) Altogether, it appears that an AMPA component is involved in combination with cholinergic mechanisms in initiating seizures. A subsequent and long-lasting recruitment of NMDA receptors is then essential in sustaining the seizures. New anticonvulsant and neuroprotective approaches using Glu antagonists against nerve agents intoxication are discussed.

  18. Analytic Solution of the Boltzmann Equation in an Expanding System.

    PubMed

    Bazow, D; Denicol, G S; Heinz, U; Martinez, M; Noronha, J

    2016-01-15

    For a massless gas with a constant cross section in a homogeneous, isotropically expanding spacetime we reformulate the relativistic Boltzmann equation as a set of nonlinear coupled moment equations. For a particular initial condition this set can be solved exactly, yielding the first analytical solution of the Boltzmann equation for an expanding system. The nonequilibrium behavior of this relativistic gas can be mapped onto that of a homogeneous, static nonrelativistic gas of Maxwell molecules.

  19. Tutoring and Multi-Agent Systems: Modeling from Experiences

    ERIC Educational Resources Information Center

    Bennane, Abdellah

    2010-01-01

    Tutoring systems become complex and are offering varieties of pedagogical software as course modules, exercises, simulators, systems online or offline, for single user or multi-user. This complexity motivates new forms and approaches to the design and the modelling. Studies and research in this field introduce emergent concepts that allow the…

  20. An Intelligent Control for the Distributed Flexible Network Photovoltaic System using Autonomous Control and Agent

    NASA Astrophysics Data System (ADS)

    Park, Sangsoo; Miura, Yushi; Ise, Toshifumi

    This paper proposes an intelligent control for the distributed flexible network photovoltaic system using autonomous control and agent. The distributed flexible network photovoltaic system is composed of a secondary battery bank and a number of subsystems which have a solar array, a dc/dc converter and a load. The control mode of dc/dc converter can be selected based on local information by autonomous control. However, if only autonomous control using local information is applied, there are some problems associated with several cases such as voltage drop on long power lines. To overcome these problems, the authors propose introducing agents to improve control characteristics. The autonomous control with agents is called as intelligent control in this paper. The intelligent control scheme that employs the communication between agents is applied for the model system and proved with simulation using PSCAD/EMTDC.

  1. Distributed adaptive fuzzy iterative learning control of coordination problems for higher order multi-agent systems

    NASA Astrophysics Data System (ADS)

    Li, Jinsha; Li, Junmin

    2016-07-01

    In this paper, the adaptive fuzzy iterative learning control scheme is proposed for coordination problems of Mth order (M ≥ 2) distributed multi-agent systems. Every follower agent has a higher order integrator with unknown nonlinear dynamics and input disturbance. The dynamics of the leader are a higher order nonlinear systems and only available to a portion of the follower agents. With distributed initial state learning, the unified distributed protocols combined time-domain and iteration-domain adaptive laws guarantee that the follower agents track the leader uniformly on [0, T]. Then, the proposed algorithm extends to achieve the formation control. A numerical example and a multiple robotic system are provided to demonstrate the performance of the proposed approach.

  2. Ocular delivery systems for topical application of anti-infective agents.

    PubMed

    Duxfield, Linda; Sultana, Rubab; Wang, Ruokai; Englebretsen, Vanessa; Deo, Samantha; Rupenthal, Ilva D; Al-Kassas, Raida

    2016-01-01

    For the treatment of anterior eye segment infections using anti-infective agents, topical ocular application is the most convenient route of administration. However, topical delivery of anti-infective agents is associated with a number of problems and challenges owing to the unique structure of the eye and the physicochemical properties of these compounds. Topical ocular drug delivery systems can be classified into two forms: conventional and non-conventional. The efficacy of conventional ocular formulations is limited by poor corneal retention and permeation resulting in low ocular bioavailability. Recently, attention has been focused on improving topical ocular delivery of anti-infective agents using advanced drug delivery systems. This review will focus on the challenges of efficient topical ocular delivery of anti-infective agents and will discuss the various types of delivery systems used to improve the treatment anterior segment infections.

  3. Multi-Agent Diagnosis and Control of an Air Revitalization System for Life Support in Space

    NASA Technical Reports Server (NTRS)

    Malin, Jane T.; Kowing, Jeffrey; Nieten, Joseph; Graham, Jeffrey s.; Schreckenghost, Debra; Bonasso, Pete; Fleming, Land D.; MacMahon, Matt; Thronesbery, Carroll

    2000-01-01

    An architecture of interoperating agents has been developed to provide control and fault management for advanced life support systems in space. In this adjustable autonomy architecture, software agents coordinate with human agents and provide support in novel fault management situations. This architecture combines the Livingstone model-based mode identification and reconfiguration (MIR) system with the 3T architecture for autonomous flexible command and control. The MIR software agent performs model-based state identification and diagnosis. MIR identifies novel recovery configurations and the set of commands required for the recovery. The AZT procedural executive and the human operator use the diagnoses and recovery recommendations, and provide command sequencing. User interface extensions have been developed to support human monitoring of both AZT and MIR data and activities. This architecture has been demonstrated performing control and fault management for an oxygen production system for air revitalization in space. The software operates in a dynamic simulation testbed.

  4. A Distributed Multi-Agent System for Collaborative Information Management and Learning

    NASA Technical Reports Server (NTRS)

    Chen, James R.; Wolfe, Shawn R.; Wragg, Stephen D.; Koga, Dennis (Technical Monitor)

    2000-01-01

    In this paper, we present DIAMS, a system of distributed, collaborative agents to help users access, manage, share and exchange information. A DIAMS personal agent helps its owner find information most relevant to current needs. It provides tools and utilities for users to manage their information repositories with dynamic organization and virtual views. Flexible hierarchical display is integrated with indexed query search-to support effective information access. Automatic indexing methods are employed to support user queries and communication between agents. Contents of a repository are kept in object-oriented storage to facilitate information sharing. Collaboration between users is aided by easy sharing utilities as well as automated information exchange. Matchmaker agents are designed to establish connections between users with similar interests and expertise. DIAMS agents provide needed services for users to share and learn information from one another on the World Wide Web.

  5. Knowledge-based reasoning to annotate noncoding RNA using multi-agent system.

    PubMed

    Arruda, Wosley C; Souza, Daniel S; Ralha, Célia G; Walter, Maria Emilia M T; Raiol, Tainá; Brigido, Marcelo M; Stadler, Peter F

    2015-12-01

    Noncoding RNAs (ncRNAs) have been focus of intense research over the last few years. Since characteristics and signals of ncRNAs are not entirely known, researchers use different computational tools together with their biological knowledge to predict putative ncRNAs. In this context, this work presents ncRNA-Agents, a multi-agent system to annotate ncRNAs based on the output of different tools, using inference rules to simulate biologists' reasoning. Experiments with data from the fungus Saccharomyces cerevisiae allowed to measure the performance of ncRNA-Agents, with better sensibility, when compared to Infernal, a widely used tool for annotating ncRNA. Besides, data of the Schizosaccharomyces pombe and Paracoccidioides brasiliensis fungi identified novel putative ncRNAs, which demonstrated the usefulness of our approach. NcRNA-Agents can be be found at: http://www.biomol.unb.br/ncrna-agents.

  6. Decentralised control for formation reorganisation of multi-agent systems using a virtual leader

    NASA Astrophysics Data System (ADS)

    Luo, Xiaoyuan; Li, Shaobao; Guan, Xinping

    2011-01-01

    In this article, we study the topology reorganisation of formations for multi-agent systems with a broken agent during motion. The cases with a broken agent in different topologies and different positions are studied, and a decentralised algorithm is proposed to reorganise the different damaged topologies of formations. The main contributions of this article include: first, a collective potential function model is designed to reorganise the topologies, and a repulsive potential function model is proposed to avoid obstacles; second, a decentralised algorithm based on potential functions is presented; third, a virtual agent is designed to be a leader as soon as an agent is damaged, and disappears once the topology is repaired. Finally, some simulation results are studied to demonstrate the efficiency of the proposed algorithm.

  7. Controllability of discrete-time multi-agent systems with directed topology and input delay

    NASA Astrophysics Data System (ADS)

    Lu, Zehuan; Zhang, Lin; Ji, Zhijian; Wang, Long

    2016-01-01

    This paper investigates the controllability of first-order and second-order discrete-time multi-agent systems with directed topology and input delay. The problem is studied in the leader-follower framework where a number of agents are selected to be leaders and serve as control inputs to all other agents. Sufficient and necessary conditions are derived for the controllability of first-order discrete-time multi-agent systems. With sampling period and feedback gain satisfying certain conditions, it is proved under three different protocols that the controllability of second-order discrete-time multi-agent systems is equivalent to that of a pair of submatrices of Laplacian matrix. In addition, the controllability of both first-order and second-order discrete-time multi-agent systems with input delay is shown, through some transformations, to be equivalent to that of the transformed non-delayed systems. Finally, some simulation examples are given to illustrate the theoretical results.

  8. Multi-agent system as a new approach to effective chronic heart failure management: key considerations.

    PubMed

    Mohammadzadeh, Niloofar; Safdari, Reza; Rahimi, Azin

    2013-09-01

    Given the importance of the follow-up of chronic heart failure (CHF) patients to reduce common causes of re-admission and deterioration of their status that lead to imposing spiritual and physical costs on patients and society, modern technology tools should be used to the best advantage. The aim of this article is to explain key points which should be considered in designing an appropriate multi-agent system to improve CHF management. In this literature review articles were searched with keywords like multi-agent system, heart failure, chronic disease management in Science Direct, Google Scholar and PubMed databases without regard to the year of publications. Agents are an innovation in the field of artificial intelligence. Because agents are capable of solving complex and dynamic health problems, to take full advantage of e-Health, the healthcare system must take steps to make use of this technology. Key factors in CHF management through a multi-agent system approach must be considered such as organization, confidentiality in general aspects and design and architecture points in specific aspects. Note that use of agent systems only with a technical view is associated with many problems. Hence, in delivering healthcare to CHF patients, considering social and human aspects is essential. It is obvious that identifying and resolving technical and non-technical challenges is vital in the successful implementation of this technology.

  9. Multi-Agent System as a New Approach to Effective Chronic Heart Failure Management: Key Considerations

    PubMed Central

    Mohammadzadeh, Niloofar; Rahimi, Azin

    2013-01-01

    Objectives Given the importance of the follow-up of chronic heart failure (CHF) patients to reduce common causes of re-admission and deterioration of their status that lead to imposing spiritual and physical costs on patients and society, modern technology tools should be used to the best advantage. The aim of this article is to explain key points which should be considered in designing an appropriate multi-agent system to improve CHF management. Methods In this literature review articles were searched with keywords like multi-agent system, heart failure, chronic disease management in Science Direct, Google Scholar and PubMed databases without regard to the year of publications. Results Agents are an innovation in the field of artificial intelligence. Because agents are capable of solving complex and dynamic health problems, to take full advantage of e-Health, the healthcare system must take steps to make use of this technology. Key factors in CHF management through a multi-agent system approach must be considered such as organization, confidentiality in general aspects and design and architecture points in specific aspects. Conclusions Note that use of agent systems only with a technical view is associated with many problems. Hence, in delivering healthcare to CHF patients, considering social and human aspects is essential. It is obvious that identifying and resolving technical and non-technical challenges is vital in the successful implementation of this technology. PMID:24195010

  10. Theoretical optimization of the removal of cryoprotective agents using a dilution-filtration system.

    PubMed

    Qiao, Heyuan; Ding, Weiping; Sun, Sijie; Gong, Liangquan; Gao, Dayong

    2014-08-21

    In the cryopreservation of blood, removing cryoprotectants from the cryopreserved blood safely and effectively is always being focused on. In our previous work, a dilution-filtration system was proposed to achieve the efficient clearance of cryoprotectants from the cryopreserved blood. In this study, a theoretical method is presented to optimize the diluent flow rate in the system to further reduce the osmotic damage to red blood cells (RBCs) and shorten the washing time necessary to remove cryoprotective agents (CPAs), based on a discrete mass transfer concept. In the method, the diluent flow rate is automatically adjusted by a program code in each cycle to maximize the clearance of CPAs, whereas the volume of RBCs is always maintained below the upper volume tolerance limit. The results show that the optimized diluent flow rate can significantly decrease the washing time of CPAs. The washing time under the optimized diluent flow rate can be reduced by over 50%, compared to the one under the fixed diluent flow rate. In addition, the advantage of our method becomes more significant when the blood flow rate is lower, the dilution region volume is larger, the initial CPA concentration is higher, or the cell-swelling limit set by the system is smaller. The proposed method for the dilution-filtration system is an ideal solution for not only guaranteeing the volume safety of RBCs but also shortening the washing time of CPAs. In practice, the optimization strategies provided here will be useful in the rapid preparation of cryopreserved blood for clinical use.

  11. Solution rheology of polyelectrolytes and polyelectrolyte-surfactant systems

    NASA Astrophysics Data System (ADS)

    Plucktaveesak, Nopparat

    The fundamental understanding of polyelectrolytes in aqueous solutions is an important branch of polymer research. In this work, the rheological properties of polyelectrolytes and polyelectrolyte/surfactant systems are studied. Various synthetic poly electrolytes are chosen with varied hydrophobicity. We discuss the effects of adding various surfactants to aqueous solutions of poly(ethylene oxide)-b-poly(propylene oxide)- b-polyethylene oxide)-g-poly(acrylic acid) (PEO-PPO-PAA) in the first chapter. Thermogelation in aqueous solutions of PEO-PPO-PAA is due to micellization caused by aggregation of poly(propylene oxide) (PPO) blocks resulting from temperature-induced dehydration of PPO. When nonionic surfactants with hydrophilic-lipophilic balance (HLB) parameter exceeding 11 or Cn alkylsulfates; n-octyl (C8), n-decyl (C 10) and n-dodecyl (C12) sulfates are added, the gelation threshold temperature (Tgel) of 1.0wt% PEO-PPO-PAA in aqueous solutions increases. In contrast, when nonionic surfactants with HLB below 11 are added, the gelation temperature decreases. On the other hand, alkylsulfates with n = 16 or 18 and poly(ethylene oxide) (PEO) do not affect the Tgel. The results imply that both hydrophobicity and tail length of the added surfactant play important roles in the interaction of PEO-PPO-PAA micelles and the surfactant. In the second chapter, the solution behavior of alternating copolymers of maleic acid and hydrophobic monomer is studied. The alternating structure of monomers with two-carboxylic groups and hydrophobic monomers make these copolymers unique. Under appropriate conditions, these carboxylic groups dissociate leaving charges on the chain. The potentiometric titrations of copolymer solutions with added CaCl2 reveal two distinct dissociation processes corresponding to the dissociation of the two adjacent carboxylic acids. The viscosity data as a function of polymer concentration of poly(isobutylene-alt-sodium maleate), poly

  12. Fusion solution for soldier wearable gunfire detection systems

    NASA Astrophysics Data System (ADS)

    Cakiades, George; Desai, Sachi; Deligeorges, Socrates; Buckland, Bruce E.; George, Jemin

    2012-06-01

    Currently existing acoustic based Gunfire Detection Systems (GDS) such as soldier wearable, vehicle mounted, and fixed site devices provide enemy detection and localization capabilities to the user. However, the solution to the problem of portability versus performance tradeoff remains elusive. The Data Fusion Module (DFM), described herein, is a sensor/platform agnostic software supplemental tool that addresses this tradeoff problem by leveraging existing soldier networks to enhance GDS performance across a Tactical Combat Unit (TCU). The DFM software enhances performance by leveraging all available acoustic GDS information across the TCU synergistically to calculate highly accurate solutions more consistently than any individual GDS in the TCU. The networked sensor architecture provides additional capabilities addressing the multiple shooter/fire-fight problems in addition to sniper detection/localization. The addition of the fusion solution to the overall Size, Weight and Power & Cost (SWaP&C) is zero to negligible. At the end of the first-year effort, the DFM integrated sensor network's performance was impressive showing improvements upwards of 50% in comparison to a single sensor solution. Further improvements are expected when the networked sensor architecture created in this effort is fully exploited.

  13. Agent-based Modeling Methodology for Analyzing Weapons Systems

    DTIC Science & Technology

    2015-03-26

    Getting as much information as possible to make these decisions, through analysis of the weapons systems benefits and costs, yields better decisions...This study has twin goals. The first is to demonstrate a sound methodology to yield the most information about benefits of a particular weapon...system. Second, we wish to provide some baseline analysis of the benefits of a new type of missile, the Small Advanced Capability Missile (SACM

  14. Evolution of a multi-agent system in a cyclical environment.

    PubMed

    Baptista, Tiago; Costa, Ernesto

    2008-06-01

    The synchronisation phenomena in biological systems is a current and recurring subject of scientific study. This topic, namely that of circadian clocks, served as inspiration to develop an agent-based simulation that serves the main purpose of being a proof-of-concept of the model used in the BitBang framework, that implements a modern autonomous agent model. Despite having been extensively studied, circadian clocks still have much to be investigated. Rather than wanting to learn more about the internals of this biological process, we look to study the emergence of this kind of adaptation to a daily cycle. To that end we implemented a world with a day/night cycle, and analyse the ways the agents adapt to that cycle. The results show the evolution of the agents' ability to gather food. If we look at the total number of agents over the course of an experiment, we can pinpoint the time when reproductive technology emerges. We also show that the agents adapt to the daily cycle. This circadian rhythm can be shown by analysing the variation on the agents metabolic rate, which is affected by the variation of their movement patterns. In the experiments conducted we can observe that the metabolic rate of the agents varies according to the daily cycle.

  15. Linear homotopy solution of nonlinear systems of equations in geodesy

    NASA Astrophysics Data System (ADS)

    Paláncz, Béla; Awange, Joseph L.; Zaletnyik, Piroska; Lewis, Robert H.

    2010-01-01

    A fundamental task in geodesy is solving systems of equations. Many geodetic problems are represented as systems of multivariate polynomials. A common problem in solving such systems is improper initial starting values for iterative methods, leading to convergence to solutions with no physical meaning, or to convergence that requires global methods. Though symbolic methods such as Groebner bases or resultants have been shown to be very efficient, i.e., providing solutions for determined systems such as 3-point problem of 3D affine transformation, the symbolic algebra can be very time consuming, even with special Computer Algebra Systems (CAS). This study proposes the Linear Homotopy method that can be implemented easily in high-level computer languages like C++ and Fortran that are faster than CAS by at least two orders of magnitude. Using Mathematica, the power of Homotopy is demonstrated in solving three nonlinear geodetic problems: resection, GPS positioning, and affine transformation. The method enlarging the domain of convergence is found to be efficient, less sensitive to rounding of numbers, and has lower complexity compared to other local methods like Newton-Raphson.

  16. Clinical and Experimental Observations with Regard to the Injection of Certain Agents (Pregl’s Solution) into Chronic Arthritic Joints

    PubMed Central

    2008-01-01

    observations, he concluded, warranted “further investigation and a more general use of Pregl’s solution in treating chronic effusion of arthritic and traumatized joints.” J.E.M. Thomson, MD is shown. Photograph is reproduced with permission and ©American Academy of Orthopaedic Surgeons. Fifty Years of Progress, 1983. References Heck CV. Commemorative Volume 1933–1983 Fifty Years of Progress. Chicago, IL: American Academy of Orthopaedic Surgeons; 1983. Heck CV. Fifty Years of Progress: In Recognition of the 50th Anniversary of the American Academy of Orthopaedic Surgeons. Chicago, IL: American Academy of Orthopaedic Surgeons; 1983. James E. M. Thomson 1889–1962. J Bone Joint Surg Am. 1963;45:206–208. Thomson JEM. Clinical and experimental observations with regard to the injection of certain agents (Pregl's solution) into chronic arthritic joints. J Bone Joint Surg Am. 1933;15:483–490. PMID:18196381

  17. Advances in the use of biologic agents for the treatment of systemic vasculitis

    PubMed Central

    Chung, Sharon A.; Seo, Philip

    2010-01-01

    Purpose of review Due to the well-known toxicities of cyclophosphamide, substantial interest exists in finding other therapies to treat primary systemic vasculitis. Biologic agents have been proposed as an alternative to cyclophosphamide for these disorders because of their recent success in treating other rheumatic diseases. This article reviews the current state-of-the-art with regards to the use of biologic agents as a treatment for systemic vasculitis. Recent findings The greatest amount of experience with these agents for the treatment of systemic vasculitis is with anti-tumor necrosis factor agents, pooled intravenous immunoglobulin, and anti-B cell therapies such as rituximab. Intravenous immunoglobulin is already a standard therapy for Kawasaki's disease, but should also be considered for the treatment of ANCA-associated vasculitis when standard therapies are either ineffective or contraindicated. Early experience with tumor necrosis factor inhibitors indicates that they may be effective for the treatment of Takayasu's arteritis, but their role in the treatment of other forms of vasculitis remains controversial. Early experience with rituximab for the treatment of several forms of vasculitis has been quite promising, but must be confirmed by ongoing randomized clinical trials. Summary Biologic agents represent the next evolution in treatment for the primary systemic vasculitides. Greater understanding of these diseases has allowed use to move further away from non-specific, highly toxic therapies towards a more directed approach. As our experience with these agents increases, they will likely form the keystone of treatment in the near future. PMID:19077713

  18. Interaction of cytotoxic agents: a rule-based system for computer-assisted cell survival analysis.

    PubMed

    Gentile, F P; Chiatti, L; Mauro, F; Briganti, G; Floridi, A; Benassi, M

    1992-01-01

    The actual effectiveness of environmental noxious agents or anticancer drugs can be fully determined only by knowing if the effects (in the present case, the cytotoxic effects) induced by a given agent are enhanced by exposure to another (or other) agent(s). Given a certain combination of agents, it is possible to distinguish three types of interaction: (a) zero interaction or additivity; (b) positive interaction or synergism; and (c) negative interaction or antagonism. In this work, the methodological problems involved in evaluating the type and level of interaction between biologically active agents are discussed and an "intelligent" approach to the problem is proposed. In particular, a prototype of a computer-assisted rule based system, named CISA (Cytotoxic Interaction and Survival Analysis), designed in a KES environment (Knowledge Engineering System) and implemented on a personal computer, is described. By constructing isoboles based on experimental cell survival data and taking into account the relative confidence intervals, the system can indicate the appropriate combinations of dosages to be tested and finally determine the type and level of interaction. The system, which represents an attempt to administer "intelligently" the experimental data, is therefore able to identify the best strategy of analysis, to carry out the data processing and to offer suggestions to the investigator about the usefulness of the data and the planning of further experiments.

  19. Synchronization of multi-agent systems with metric-topological interactions.

    PubMed

    Wang, Lin; Chen, Guanrong

    2016-09-01

    A hybrid multi-agent systems model integrating the advantages of both metric interaction and topological interaction rules, called the metric-topological model, is developed. This model describes planar motions of mobile agents, where each agent can interact with all the agents within a circle of a constant radius, and can furthermore interact with some distant agents to reach a pre-assigned number of neighbors, if needed. Some sufficient conditions imposed only on system parameters and agent initial states are presented, which ensure achieving synchronization of the whole group of agents. It reveals the intrinsic relationships among the interaction range, the speed, the initial heading, and the density of the group. Moreover, robustness against variations of interaction range, density, and speed are investigated by comparing the motion patterns and performances of the hybrid metric-topological interaction model with the conventional metric-only and topological-only interaction models. Practically in all cases, the hybrid metric-topological interaction model has the best performance in the sense of achieving highest frequency of synchronization, fastest convergent rate, and smallest heading difference.

  20. Synchronization of multi-agent systems with metric-topological interactions

    NASA Astrophysics Data System (ADS)

    Wang, Lin; Chen, Guanrong

    2016-09-01

    A hybrid multi-agent systems model integrating the advantages of both metric interaction and topological interaction rules, called the metric-topological model, is developed. This model describes planar motions of mobile agents, where each agent can interact with all the agents within a circle of a constant radius, and can furthermore interact with some distant agents to reach a pre-assigned number of neighbors, if needed. Some sufficient conditions imposed only on system parameters and agent initial states are presented, which ensure achieving synchronization of the whole group of agents. It reveals the intrinsic relationships among the interaction range, the speed, the initial heading, and the density of the group. Moreover, robustness against variations of interaction range, density, and speed are investigated by comparing the motion patterns and performances of the hybrid metric-topological interaction model with the conventional metric-only and topological-only interaction models. Practically in all cases, the hybrid metric-topological interaction model has the best performance in the sense of achieving highest frequency of synchronization, fastest convergent rate, and smallest heading difference.