93 research outputs found
The MeSsI (merging systems identification) algorithm and catalogue
Merging galaxy systems provide observational evidence of the existence of dark matter and constraints on its properties. Therefore, statistically uniform samples of merging systems would be a powerful tool for several studies. In this paper, we present a new methodology for the identification of merging systems and the results of its application to galaxy redshift surveys.We use as a starting point amock catalogue of galaxy systems, identified using friendsof- friends algorithms, that have experienced a major merger, as indicated by its merger tree. By applying machine learning techniques in this training sample, and using several features computed from the observable properties of galaxy members, it is possible to select galaxy groups that have a high probability of having experienced a major merger. Next, we apply a mixture of Gaussian techniques on galaxy members in order to reconstruct the properties of the haloes involved in such mergers. This methodology provides a highly reliable sample of merging systems with low contamination and precisely recovered properties. We apply our techniques to samples of galaxy systems obtained from the Sloan Digital Sky Survey Data Release 7, theWide-Field Nearby Galaxy-Cluster Survey (WINGS) and the Hectospec Cluster Survey (HeCS). Our results recover previously known merging systems and provide several new candidates. We present their measured properties and discuss future analysis on current and forthcoming samples.Fil: De Los Rios, Martín. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Astronomía Teórica y Experimental. Universidad Nacional de Córdoba. Observatorio Astronómico de Córdoba. Instituto de Astronomía Teórica y Experimental; ArgentinaFil: Dominguez, Mariano. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Astronomía Teórica y Experimental. Universidad Nacional de Córdoba. Observatorio Astronómico de Córdoba. Instituto de Astronomía Teórica y Experimental; ArgentinaFil: Paz, Dante Javier. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Astronomía Teórica y Experimental. Universidad Nacional de Córdoba. Observatorio Astronómico de Córdoba. Instituto de Astronomía Teórica y Experimental; ArgentinaFil: Merchan, Manuel Enrique. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Astronomía Teórica y Experimental. Universidad Nacional de Córdoba. Observatorio Astronómico de Córdoba. Instituto de Astronomía Teórica y Experimental; Argentina. Universidad Nacional de Córdoba. Observatorio Astronómico de Córdoba; Argentin
Self-organizing multi-agent system for management and planning surveillance routes
This paper presents the THOMAS architecture, specially designed to model open multi-agent systems, and its application in the development of a multi-agent system for managing and planning surveillance routes for security personnel. THOMAS uses agents with reasoning and planning capabilities. These agents can perform a dynamic self-organization when they detect changes in the environment. THOMAS is appropriate for developing systems in highly dynamic environments similar to the one presented in this study, as demonstrated by the results obtained after having applied the system to a case study.Web of Science3151100108
Self-Organizing Multi-Agent System for Management and Planning Surveillance Routes
This paper presents the THOMAS architecture, specially designed to model open multi-agent systems, and its application in the development of a multi-agent system for managing and planning surveillance routes for security personnel. THOMAS uses agents with reasoning and planning capabilities. These agents can perform a dynamic self-organization when they detect changes in the environment. THOMAS is appropriate for developing systems in highly dynamic environments similar to the one presented in this study, as demonstrated by the results obtained after having applied the system to a case study
Mitigation of the ground reflection effect in real-time locating systems based on wireless sensor networks by using artificial neural networks
Wireless sensor networks (WSNs) have become much more relevant in recent years, mainly because they can be used in a wide diversity of applications. Real-time locating systems (RTLSs) are one of the most promising applications based on WSNs and represent a currently growing market. Specifically, WSNs are an ideal alternative to develop RTLSs aimed at indoor environments where existing global navigation satellite systems, such as the global positioning system, do not work correctly due to the blockage of the satellite signals. However, accuracy in indoor RTLSs is still a problem requiring novel solutions. One of the main challenges is to deal with the problems that arise from the effects of the propagation of radiofrequency waves, such as attenuation, diffraction, reflection and scattering. These effects can lead to other undesired problems, such as multipath. When the ground is responsible for wave reflections, multipath can be modeled as the ground reflection effect. This paper presents an innovative mathematical model for improving the accuracy of RTLSs, focusing on the mitigation of the ground reflection effect by using multilayer perceptron artificial neural networks.Wireless sensor networks (WSNs) have become much more relevant in recent years, mainly because they can be used in a wide diversity of applications. Real-time locating systems (RTLSs) are one of the most promising applications based on WSNs and represent a currently growing market. Specifically, WSNs are an ideal alternative to develop RTLSs aimed at indoor environments where existing global navigation satellite systems, such as the global positioning system, do not work correctly due to the blockage of the satellite signals. However, accuracy in indoor RTLSs is still a problem requiring novel solutions. One of the main challenges is to deal with the problems that arise from the effects of the propagation of radiofrequency waves, such as attenuation, diffraction, reflection and scattering. These effects can lead to other undesired problems, such as multipath. When the ground is responsible for wave reflections, multipath can be modeled as the ground reflection effect. This paper presents an innovative mathematical model for improving the accuracy of RTLSs, focusing on the mitigation of the ground reflection effect by using multilayer perceptron artificial neural networks
Taxa de crescimento e fragmentação Miofibrilar diferenciadas em ratos submetidos a restrição alimentar e realimentação
Feed regimens alter muscle growth rate, hence they might impact the proteolytic system involved in tenderization during meat conditioning. The aim of this project was to verify the effects of feed restriction regimens on muscular and animal growth and their impact on postmortem myofibrillar fragmentation. The regimens were: 1) Feeding ad libitum for 11 d (Al/2); 2) Feed restriction (60% of Net Energy for maintenance - NEm) for 11 d (Rt/2); 3) Ad libitum for 22 d (Al); 4) Ad libitum for 4 d and feed restriction (60% NEm) for 18 d (Rt); 5) Ad libitum for 19 d and 3 d of fast (Ft); 6) Feed restriction (60% NEm) for 11 d and ad libitum until 22 d (Ral). The regimens Al/2 and Rt/2 had different intestine weights (19.3 ± 1.1 and 15.8 ± 1.9 g, respectively; P < 0.07). At 22 d, Al animals had higher (P < 0.07) intestine weight (21.8 ± 3.8). Moreover, Ral animals had heavier intestine (19.9 ± 1.5) as compared to Rt (16.6 ± 1.6) or Ft (12.8 ± 1.9). The intestine/live weight percentage ratio was lower (P < 0.05) for Ft (6.3%) as compared to Al (8.4%) and to Ral (9.2%), but it was similar to Rt (7.6%). Liver weight (g) in the Ral (9.5 ± 1.1) did not differ from Al (10.7 ± 2.5) or Rt (8.5 ± 1.1), although the two latter were different (P < 0.05). There was an effect of feed restriction over muscle protein degradation verified by Myofibrillar Fragmentation Index (MFI). The animals at Rt, Ft or Ral showed the lowest MFI 0d (42 ± 1.9; 40 ± 2.7; 40 ± 3.6; respectively) and MFI 5d (77 ± 2.7; 74 ± 3.0; 74 ± 2.9; respectively) as compared to Al, whose indexes were 54 ± 3.0 and 82 ± 3.3. Even though the MFI 5d were lower for the restricted animals, the rates of fragmentation postmortem were higher. Feed restriction altered myofibrillar protein degradation, reflected in lower extended fragmentation of the myofibrils.Regimes alimentares alteram a taxa de crescimento muscular, e podem impactar o sistema proteolítico envolvido no amaciamento da carne durante maturação. O objetivo do trabalho foi verificar a existência de reflexo do regime alimentar sobre crescimento animal e muscular, e o impacto na fragmentação miofibrilar pós-morte. Os regimes foram: 1) Consumo ad libitum por 11 d (Al/2); 2) Restrição alimentar (60% energia de mantença - NEm) por 11 d (Rt/2); 3) Ad libitum por 22 d (Al); 4) Ad libitum por 4 d e restrição alimentar (60% NEm) por 18 d (Rt); 5) Ad libitum por 19 d e 3 d de jejum (Ft); 6) Restrição alimentar (60% NEm) por 11 d e ad libitum até 22 d (Ral). Os regimes Al/2 e Rt/2 apresentaram diferenças no peso de intestino (19,3 ± 1,1 e 15,8 ± 1,9 g, respectivamente; P < 0,07). Nos 22 d, o regime Al resultou em intestinos mais pesados (P < 0,07; 21,8 ± 3,8). Além disso, os animais do regime Ral tiveram maiores pesos de intestino (19,9 ± 1,5) comparados com Rt (16,6 ± 1,6) ou Ft (12,8 ± 1,9). A relação intestino/peso vivo foi menor (P < 0,05) para Ft (6,3%) comparado com Al (8,4%) e com Ral (9,2%), mas foi similar ao Rt (7,6%). O peso do fígado (g) nos animais do regime Ral (9,5 ± 1,1) não diferiu do regime Al (10,7 ± 2,5) ou Rt (8,5 ± 1,1), sendo que os dois últimos foram diferentes (P < 0,05). Houve efeito da restrição alimentar sobre a degradação da proteína muscular verificada pelo Índice de Fragmentação miofibrilar (MFI). Os animais de Rt, Ft ou Ral mostraram os menores valores de MFI 0d (42 ± 1,9; 40 ± 2,7; 40 ± 3,6; respectivamente) e MFI 5d (77 ± 2,7; 74 ± 3,0; 74 ± 2,9; respectivamente) comparados com Al onde os índices foram 54 ± 3,0 e 82 ± 3,3, respectivamente. Embora os animais que experimentaram alguma restrição alimentar tenham apresentado menor MFI 5d, as sua taxas de fragmentação pós-morte foram maiores. Restrição alimentar alterou a degradação da proteína miofibrilar, refletida na menor extensão da fragmentação das miofibrilas
Construcción de un catálogo de cúmulos de galaxias en proceso de colisión
En este trabajo presentamos los primeros resultados de la identificación de cúmulos de galaxias en colisión en catálogos de galaxias con mediciones de corrimiento al rojo (SDSS, 2DF) e introducimos la metodología. Calibramos un método mediante el estudio de los árboles de fusión de cúmulos en un catálogo simulado basado en un modelo semianalítico completo de formación de galaxias además de la simulación cosmológica Millenium. También discutimos acciones futuras para estudiar nuestra muestra de cúmulos de galaxias en colisión, incluidas las observaciones de rayos X y la reconstrucción masiva obtenida mediante el uso de lentes gravitacionales débiles.In this work we present first results of the identification of colliding galaxy clusters in galaxy catalogs with redshift measurements (SDSS, 2DF), and introduce the methodology. We calibrated a method by studying the merger trees of clusters in a mock catalog based on a full-blown semi-analytic model of galaxy formation on top of the Millenium cosmological simulation. We also discuss future actions for studding our sample of colliding galaxy clusters, including x-ray observations and mass reconstruction obtained by using weak gravitational lenses.Fil: de Los Rios, Martín Emilio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Astronomía Teórica y Experimental. Universidad Nacional de Córdoba. Observatorio Astronómico de Córdoba. Instituto de Astronomía Teórica y Experimental; ArgentinaFil: Dominguez, M. J.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Astronomía Teórica y Experimental. Universidad Nacional de Córdoba. Observatorio Astronómico de Córdoba. Instituto de Astronomía Teórica y Experimental; ArgentinaFil: Paz, Dante Javier. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Astronomía Teórica y Experimental. Universidad Nacional de Córdoba. Observatorio Astronómico de Córdoba. Instituto de Astronomía Teórica y Experimental; Argentin
Ambient Intelligence Based Architecture for Automated Dynamic Environments.
This paper presents an Ambient Intelligence based architecture that uses intelligent agents with reasoning and planning mechanisms. The agents have the ability to obtain automatic and real time information about the context using a set of technologies, such as radio frequency identification, wireless networks and wireless control devices. The architecture can be implemented on a wide diversity of dynamic environments. A case study is presented, describing the main characteristics of the planning mechanism supported by the architecture, implemented in a geriatric residence, giving the agents a high level of autonomy and flexibility for solving problems
A Case-Based Planning Mechanism for a Hardware-Embedded Reactive Agents Platform
Wireless Sensor Networks is a key technology for gathering relevant in- formation from different sources. In this sense, Multi-Agent Systems can facilitate the integration of heterogeneous sensor networks and expand the sensors’ capa- bilities changing their behavior dynamically and personalizing their reactions. Both Wireless Sensor Networks and Multi-Agent Systems can be successfully applied to different management scenarios, such as logistics, supply chain or pro- duction. The Hardware-Embedded Reactive Agents (HERA) platform allows developing applications where agents are directly embedded in heterogeneous wireless sensor nodes with reduced computational resources. This paper presents the reasoning mechanism included in HERA to provide HERA Agents with Case- Based Planning features that allow solving problems considering past experiences.
Combining Improved FYDPS Neural Networks and Case-Based Planning — A Case Study
This paper presents a hybrid deliberative architecture based on the concept of CBPBDI agent. A CBP-BDI agent is a BDI agent that incorporates a CBP reasoning engine. The work here presented focuses in the development of the CBP internal structure. The planning mechanism has been implemented by means of a novel FYDPS neural network. The system has been tested and this paper presents the results obtained
Intelligent environment for monitoring Alzheimer patients, agent technology for health care
This paper presents an autonomous intelligent agent developed for monitoring Alzheimer patients' health care in execution time in geriatric residences. The AGALZ (Autonomous aGent for monitoring ALZheimer patients) is an autonomous deliberative case-based planner agent designed to plan the nurses' working time dynamically, to maintain the standard working reports about the nurses' activities, and to guarantee that the patients assigned to the nurses are given the right care. The agent operates in wireless devices and is integrated with complementary agents into a multi-agent system, named ALZ-MAS (ALZheimer Multi-Agent System), capable of interacting with the environment. AGALZ description, its relationship with the complementary agents, and preliminary results of the multi-agent system prototype in a real environment are presented
- …