A look at the relationship between industrial dynamics and aggregate fluctuations

The firmly established evidence of right-skewness of the firms’ size distribution is generally modelled recurring to some variant of the Gibrat’s Law of Proportional Effects. In spite of its empirical success, this approach has been harshly criticized on a theoretical ground due to its lack of economic contents and its unpleasant long-run implications. In this chapter we show that a right-skewed firms’ size distribution, with its upper tail scaling down as a power law, arises naturally from a simple choice-theoretic model based on financial market imperfections and a wage setting relationship. Our results rest on a multi-agent generalization of the prey-predator model, firstly introduced into economics by Richard Goodwin forty years ago.Firm size; Prey-predator model; Business Fluctuations

Efecto regenerador del ácido hialurónico en defectos óseos circunferenciales en ratas albinas Wistar.

Objective: To determine the regenerating effect of hyaluronic acid on circumferential bone defects in albino Wistar rats. Material and Methods: An experimental type study was designed and carried out with 15 albino male Wistar rats, 4 months old and weighing between 250 and 350 grams. Two circumferential bone defects 3mm in diameter and 0.8mm deep were created in the calvaria of the parietal bone (on both sides of the midline). One defect was filled with a demineralized bone matrix (control group); while the other defect was filled with the combination of a demineralized bone matrix plus hyaluronic acid (experimental group). Five experimental rats were euthanized at 30, 60 and 90 days after surgery and they were histologically evaluated following the parameters proposed by Heiple. Results: The experimental group presented a better degree of bone regeneration at 30 and 60 postoperative days. Conclusion: Hyaluronic acid is effective in bone regeneration of circumferential bone defects.Objetivo: Determinar el efecto regenerador del ácido hialurónico en defectos óseos circunferenciales en ratas albinas Wista. Material y Métodos: Se diseñó un estudio de tipo experimental y se trabajó con 15 ratas albinas Wistar (todas macho) de 4 meses de edad y con un peso entre 250 a 350 gr. Se crearon en todas 2 defectos óseos circunferenciales de 3mm de diámetro y 0.8 mm de profundidad en la calota del hueso parietal (a ambos lados de la línea media). Un defecto fue rellenado con una matriz ósea desmineralizada (grupo control); mientras que el otro defecto fue rellenado con la combinación de una matriz ósea desmineralizada más el ácido hialurónico (grupo experimental). Se realizó la eutanasia a 05 ratas de experimentación a los 30, 60 y 90 días postquirúrgicos y se evaluaron histológicamente siguiendo los parámetros propuestos por Heiple. Resultados: El grupo experimental presentó un mejor grado de regeneración ósea en los 30 y 60 días postoperatorios. Conclusiones: El ácido hialurónico es eficaz en la regeneración ósea de defectos óseos circunferenciales

Engineering Multimedia-Aware Personalized Ubiquitous Services

Ubiquitous computing focusing on users and tasks instead of devices and singular applications is an attractive vision for the future. Especially the idea of nomadic, mobile users poses new challenges on hardware and software. Mobile devices provide vastly different presentation capabilities and need to integrate into heterogeneous environments. Network bandwidth is far from being constant and services may be available only when online. This paper presents MUNDO, an infrastructure for ubiquitous computing that addresses these challenges. The infrastructure is intended to be non-monolithic with its parts supporting mobile computing using multi-modal user interfaces, mobile data delivery, and ad-hoc communication and networking

Demand Distribution Dynamics in Creative Industries: the Market for Books in Italy

We studied the distribution dynamics of the demand for books in Italy. We found that for each of the three broad sub-markets into which the book publishing industry can be classified - Italian novels, foreign novels and non-fiction - sales over a three-year sample can be adequately fitted by a power law distribution. Our results can be plausibly interpreted in terms of a model of interactions among buyers exchanging information on the books they buy.Book publishing industry; Information transmission; Power law distribution

Agent-oriented domain-specific language for the development of intelligentdistributed non-axiomatic reasoning agents

У дисертацији је представљен прототип агентског, домен-оријентисаног језика ALAS. Основни мотиви развоја ALAS језика су подршка дистрибуираном не-аксиоматском резоновању као и омогућавање интероперабилности и хетерогене мобилности Siebog агената јер је приликом анализе постојећих агентских домен-оријентисаних језика утврђено да ни један језик не подржава ове захтеве. Побољшање у односу на сличне постојеће агентске, домен-оријентисане језике огледа се и у програмским конструктима које нуди ALAS језик а чија је основна сврха писање концизних агената који се извршавају у специфичним доменима.U disertaciji je predstavljen prototip agentskog, domen-orijentisanog jezika ALAS. Osnovni motivi razvoja ALAS jezika su podrška distribuiranom ne-aksiomatskom rezonovanju kao i omogućavanje interoperabilnosti i heterogene mobilnosti Siebog agenata jer je prilikom analize postojećih agentskih domen-orijentisanih jezika utvrđeno da ni jedan jezik ne podržava ove zahteve. Poboljšanje u odnosu na slične postojeće agentske, domen-orijentisane jezike ogleda se i u programskim konstruktima koje nudi ALAS jezik a čija je osnovna svrha pisanje konciznih agenata koji se izvršavaju u specifičnim domenima.The dissertation presents the prototype of an agent-oriented, domainspecific language ALAS. The basic motives for the development of the ALAS language are support for distributed non-axiomatic reasoning, as well as enabling the interoperability and heterogeneous mobility of agents, because it is concluded by analysing existing agent-oriented, domainspecific languages, that there is no language that supports these requirements. The improvement compared to similar existing agentoriented, domain-specific languages are also reflected in program constructs offered by ALAS language, whose the main purpose is to enable writing the concise agents that are executed in specific domains

Inteligentni multiagentski sistemi zasnovani na distribuiranom ne-aksiomatskom rezonovanju

The agent technology represents one of the most consistent approaches to distributed artificial intelligence. Agents are characterized by autonomous, reactive, proactive, and social behavior. In addition, more complex, intelligent agents are often defined in terms of human-like mental attitudes, such as beliefs, desires, and intentions. This thesis deals with software agents and multiagent systems in several ways. First, it defines a new reasoning architecture for intelligent agents called Distributed Non-Axiomatic Reasoning System (DNARS). Instead of the popular Belief-Intention-Desire model, it uses Non-Axiomatic Logic, a formalism developed for the domain of articial general intelligence. DNARS is highly-scalable, capable of answering questions and deriving new knowledge over large knowledge bases, while, at the same time, concurrently serving large numbers of external clients.  Secondly, the thesis proposes a novel agent runtime environment named Siebog. Based on the modern web and enterprise stan-dards, Siebog tries to reduce the gap between the agent technology and industrial applications. Like DNARS, Siebog is a distributed system. Its server side runs on computer clusters and provides advanced functionalities, such as automatic agent load-balancing and fault-tolerance. The client side, on the other hand, runs inside web browsers, and supports a wide variety of hardware and software platforms. Finally, Siebog depends on DNARS for deploying agents with unique reasoning capabilities.Agentska tehnologija predstavlja dosledan pristup razvoju distribuirane veštačke  inteligencije. Ono što agente izdvaja od ostalih pristupa su autonomno, reaktivino,  pro-aktivno, i socijalno ponašanje. Pored toga, kompleksniji, inteligentni agenti se često definišu koristeći ljudske mentalne konstrukcije, kao sto su verovanja, želje i namere. Disertacija se bavi softverskim agentima i multiagentskim sistemima sa nekoliko aspekata. Prvo, definisana je nova  arhitektura za rasuđivanje sa primenom u razvoju  inteligentnih agenata, nazvana Distribuirani sistem za ne-aksiomatsko rasuđivanje  (eng. Distributed Non-Axiomatic Reasoning System) (DNARS). Umesto popularnog   BDI modela za razvoj inteligentnih agenata (eng. Belief-Desire-Intention),  arhitektura  se zasniva na tzv. ne-aksiomatskoj logici, formalizmu razvijenom u domenu veštačke  opšte inteligencije. DNARS je skalabilan softverski sistem, sposoban da odgovara na   pitanja i da izvodi nove zaključke na osnovu veoma velikih  baza znanja, služeći pri   tome veliki broj klijenata. Zatim, u disertaciji je predložena nova multiagentska platforma nazvana Siebog. Siebog je zasnovan na modernim standardima za razvoj veb aplikacija, čime pokušava da smanji razliku izmedu multiagentskih sistema i sistema koji se koriste u industriji. Kao DNARS, i Siebog je distribuiran sistem. Na serverskoj strani, Siebog se izvršava na računarskim klasterima, pružajući napredne funkcionalnosti, poput automatske distribucije agenata i otpornosti na greške. Sa klijentske strane, Siebog se izvršava u veb pretrazivačima i podržava široku lepezu hardverskih i softverskih platformi. Konačno, Siebog se oslanja na DNARS za ravoj agenata sa jedinstvenim sposobnostima za rasuđivanje

Engineering Automation for Reliable Software Interim Progress Report (10/01/2000 - 09/30/2001)

Prepared for: U.S. Army Research Office P.O. Box 12211 Research Triangle Park, NC 27709-2211The objective of our effort is to develop a scientific basis for producing reliable software that is also flexible and cost effective for the DoD distributed software domain. This objective addresses the long term goals of increasing the quality of service provided by complex systems while reducing development risks, costs, and time. Our work focuses on "wrap and glue" technology based on a domain specific distributed prototype model. The key to making the proposed approach reliable, flexible, and cost-effective is the automatic generation of glue and wrappers based on a designer's specification. The "wrap and glue" approach allows system designers to concentrate on the difficult interoperability problems and defines solutions in terms of deeper and more difficult interoperability issues, while freeing designers from implementation details. Specific research areas for the proposed effort include technology enabling rapid prototyping, inference for design checking, automatic program generation, distributed real-time scheduling, wrapper and glue technology, and reliability assessment and improvement. The proposed technology will be integrated with past research results to enable a quantum leap forward in the state of the art for rapid prototyping.U. S. Army Research Office P.O. Box 12211 Research Triangle Park, NC 27709-22110473-MA-SPApproved for public release; distribution is unlimited

Happiness, Social Preferences and Economic Policy

Two recent research branches have called into question the hypothesis that the economic subject is rational and egoist, that is to say, that his/her sole objective is to maximize his/her own personal material interests. In the first place, the literature on the so-called happiness paradox has seriously put in question the given, widely diffused not only in the doctrine but also in the common perception, that a higher level of material welfare necessarily leads to a greater level of personal well being or happiness, on an individual level but even more so on a collective one. In the second place, experimental economics has produced a wealth of results that, vice versa, confirm something that the common sense and the personal observation of many had already suspected: economic subjects do not all and not always pursue exclusively the maximization of their own personal interests. This work critically discusses these two approaches and analyzes their interesting implications in economic policy

A smartwater metering deployment based on the fog computing paradigm

In this paper, we look into smart water metering infrastructures that enable continuous, on-demand and bidirectional data exchange between metering devices, water flow equipment, utilities and end-users. We focus on the design, development and deployment of such infrastructures as part of larger, smart city, infrastructures. Until now, such critical smart city infrastructures have been developed following a cloud-centric paradigm where all the data are collected and processed centrally using cloud services to create real business value. Cloud-centric approaches need to address several performance issues at all levels of the network, as massive metering datasets are transferred to distant machine clouds while respecting issues like security and data privacy. Our solution uses the fog computing paradigm to provide a system where the computational resources already available throughout the network infrastructure are utilized to facilitate greatly the analysis of fine-grained water consumption data collected by the smart meters, thus significantly reducing the overall load to network and cloud resources. Details of the system's design are presented along with a pilot deployment in a real-world environment. The performance of the system is evaluated in terms of network utilization and computational performance. Our findings indicate that the fog computing paradigm can be applied to a smart grid deployment to reduce effectively the data volume exchanged between the different layers of the architecture and provide better overall computational, security and privacy capabilities to the system

Easing software development for pervasive computing environments

textIn recent years pervasive computing has enjoyed an amazing growth in both research and commercial fields. Not only have the number of available techniques and tools expanded, but the number of actual deployments has been underwhelming. With this growth however, we are also experiencing a divergence of software interfaces, languages, and techniques. This leads to an understandably confusing landscape which needlessly burdens the development of applications. It is our sincere hope that through the use of specialized interfaces, languages, and tools, we can make pervasive computing environments more approachable and efficient to software developers and thereby increase the utility and value of pervasive computing applications. In this dissertation, we present a new method for creating and managing the long-term conversations between peers in pervasive computing environments. The Application Sessions Model formally describes these conversations and specifies techniques for managing them over their lifetimes. In addition to these descriptions, this dissertation presents a prototype implementation of the model and results from its use for realistic scenarios. To address the Application Sessions Model's unique needs for resource discovery in pervasive computing environments, we also present the Evolving Tuples Model. This model is also formally defined in this dissertation and practical examples are used to clarify its features. A prototype for both sensor hardware and software simulation of this model is described along with results characterizing the behavior of the model. The models, prototypes, and evaluations of both models presented here form the basis of a new and interesting line of research into support structures for pervasive computing application development.Electrical and Computer Engineerin