Computing Strong and Weak Permissions in Defeasible Logic

In this paper we propose an extension of Defeasible Logic to represent and compute three concepts of defeasible permission. In particular, we discuss different types of explicit permissive norms that work as exceptions to opposite obligations. Moreover, we show how strong permissions can be represented both with, and without introducing a new consequence relation for inferring conclusions from explicit permissive norms. Finally, we illustrate how a preference operator applicable to contrary-to-duty obligations can be combined with a new operator representing ordered sequences of strong permissions which derogate from prohibitions. The logical system is studied from a computational standpoint and is shown to have liner computational complexity

Strategic Argumentation is NP-Complete

In this paper we study the complexity of strategic argumentation for dialogue games. A dialogue game is a 2-player game where the parties play arguments. We show how to model dialogue games in a skeptical, non-monotonic formalism, and we show that the problem of deciding what move (set of rules) to play at each turn is an NP-complete problem

The Degeneracy of Galaxy Formation Models

We develop a new formalism for modeling the formation and evolution of galaxies within a hierarchical universe. Similarly to standard semi-analytical models we trace galaxies inside dark-matter merger-trees. The formalism includes treatment of feedback, star-formation, cooling, smooth accretion, gas stripping in satellite galaxies, and merger-induced star bursts. However, unlike in other models, each process is assumed to have an efficiency which depends only on the host halo mass and redshift. This allows us to describe the various components of the model in a simple and transparent way. By allowing the efficiencies to have any value for a given halo mass and redshift, we can easily encompass a large range of scenarios. To demonstrate this point, we examine several different galaxy formation models, which are all consistent with the observational data. Each model is characterized by a different unique feature: cold accretion in low mass haloes, zero feedback, stars formed only in merger-induced bursts, and shutdown of star-formation after mergers. Using these models we are able to examine the degeneracy inherent in galaxy formation models, and look for observational data that will help to break this degeneracy. We show that the full distribution of star-formation rates in a given stellar mass bin is promising in constraining the models. We compare our approach in detail to the semi-analytical model of De Lucia & Blaizot. It is shown that our formalism is able to produce a very similar population of galaxies once the same median efficiencies per halo mass and redshift are being used. We provide a public version of the model galaxies on our web-page, along with a tool for running models with user-defined parameters. Our model is able to provide results for a 62.5 h^{-1} Mpc box within just a few seconds.Comment: Accepted for publication in MNRAS. Fig 6 & 7 corrected. For the project page which allows running your own model, see http://www.mpa-garching.mpg.de/galform/sesam

Respiratory disease and the role of oral bacteria

The relationship between oral health and systemic conditions, including the association between poor oral hygiene, periodontal disease, and respiratory disease, has been increasingly debated over recent decades. A considerable number of hypotheses have sought to explain the possible role of oral bacteria in the pathogenesis of respiratory diseases, and some clinical and epidemiological studies have found results favoring such an association. This review discusses the effect of oral bacteria on respiratory disease, briefly introduces the putative biological mechanisms involved, and the main factors that could contribute to this relationship. It also describes the role of oral care for individuals who are vulnerable to respiratory infections

Kinematics and history of the solar neighbourhood revisited

We use proper motions and parallaxes from the new reduction of Hipparcos data and Geneva-Copenhagen radial velocities for a complete sample of ~15000 main-sequence and subgiant stars, and new Padova isochrones to constrain the kinematics and star-formation history of the solar neighbourhood. We rederive the solar motion and the structure of the local velocity ellipsoids. When the principal velocity dispersions are assumed to increase with time as t^\beta, the index \beta is larger for \sigma_W (\beta_W~0.45) than for \sigma_U (\beta_U~0.31). For the three-dimensional velocity dispersion we obtain \beta=0.35. We exclude saturation of disc heating after ~3 Gyr as proposed by Quillen & Garnett(2000). Saturation after >~4 Gyr combined with an abrupt increase in velocity dispersion for the oldest stars cannot be excluded. For all our models the star-formation rate is declining, being a factor 2-7 lower now than it was at the beginning. Models in which the SFR declines exponentially favour very high disc ages between 11.5 and 13 Gyr and exclude ages below ~10.5 Gyr as they yield worse fits to the number density and velocity dispersion of red stars. Models in which the SFR is the sum of two declining exponentials representing the thin and thick discs favour ages between 10.5 and 12 Gyr with a lower limit of ~10.0 Gyr. Although in our models the star-formation rate peaked surprisingly early, the mean formation time of solar-neighbourhood stars is later than in ab-initio models of galaxy formation, probably on account of weaknesses in such models.Comment: 18 pages, 18 figures, accepted for publication in MNRA

Towards a Methodology for Business Process Revision under Norm and Outcome Compliance

See English abstract.Business Process Management approach allows an organisation to control every aspect of its internal processes (also called business processes) to improve them continuously, and to achieve at the same time the organisational objectives (or goals) business processes are built for. When the enterprise is seen as an entity embedded in an environment regulated by norms, the concept of norm compliance comes into play. Norm compliance is the alignment of the formal specifications of a (set of) business process(es), and the formal specifications of the set of norms governing the surrounding environment. While this topic gave rise through the years to an entire research field (Business Process Compliance), to the best of our knowledge little attention has been given on how enterprises should behave in case of normative changes, or what are the actual implications on regulatory compliance in case of deliberatory process changes. In this situation, organisations have to face important questions. Are business processes still compliant with the normative? And if not, is it possible to recover compliance? How to revise business processes and adjust their behaviour with respect to these changes? Another significant aspect to take into consideration is that the concept of compliance \u2013 intended as compliance with respect to a normative system \u2013 is not sufficient when we have to revise an internal process. In fact, the revision process has to take care both of the achievement of the objectives an organisation aims at (goal compliance) and the norms in force in the environment (norm compliance), and must satisfy both compliances at the same time. In this direction, negligible efforts have been spent on formalising a framework where norm and goal compliance are equally treated as fundamental parameters of a business process. This is the first contribution of the present dissertation. We propose a logic formalisation that models organisations as rational agents equipped with three kind of knowledge: (i) the beliefs of the agent, that is to say, a set of statements describing how the agent perceives the surrounding environment, and how the agent is able to interact with the environment based on her capabilities, (ii) the norms the agent must obey based on several contexts, and (iii) her objectives, that is to say, a list of desired purposes the agent is willing to commit. In the literature of agent systems, agents are driven by several goal-like attitudes, such as desires, goals and intentions; these attitudes affect the way an agent behaves and modifies the environment. In our framework, the interactions between beliefs, norms, and goal-like attitudes are modelled by following a brand new idea: goal-like attitudes are deemed as different facets of the same phenomenon, namely an outcome, which is defined as something (typically, a state of affairs) that an agent expects to achieve or that can possibly occur. Goal-like attitudes are then defined through a filtering mechanism of outcomes with respect to norms and beliefs. In this way, each single goal-like attitude is defined by means of the others, and the entire deliberative process of the agent consists of computing what are the goal-like attitudes that hold in a specific scenario. The benefit offered by our solution is twofold. First, the logic we propose is able to fully formalise the intuitions of being compliant with a set of norms and a set of outcomes. Second, norm and outcome compliance are efficiently determined by exploiting the inferential mechanism of such a logic. The second contribution of this dissertation regards the problem of finding automatic methodologies to revise a non-compliant business process in case of breach of norms or not fulfilment of some internal outcomes, in order to obtain a process that agrees with the normative regulation in force and joins the business objectives once the revision process ends. This research challenge is justified by several motivations. Above all, nowadays compliance revision is mainly a manual work and poorly supported by ad-hoc software or automatic procedures, and thus extremely costly in terms of time and money. A first step towards automatic compliance recovery consists in identifying all admissible instances of the business process revision problem in the framework we provide. Our analysis tackles two major issues. The first one regards how to determine conditions for the existence of solutions for each problem instance. We address the problem by exploiting proof tag analysis. Proof tag analysis is a proof-based analysis which efficiently describes properties (relevant for compliance management/revision) of elements inside a theory in our framework. The second issue considers the computational aspects of the problem instances. In this respect, we determine the complexity boundaries of a specific problem instance among those isolated

ANALISIS HASIL PENGUJIAN SONDIR UNTUK MENGETAHUI PENINGKATAN KEKUATAN TANAH SANGAT LUNAK DI LOKASI GATE HOUSE DALAM PEKERJAAN “GROUTING AT SEMARANG PUMPING STATION & RETARDING POND”

The water building structure at the mouth of the Semarang river as a flood prevention building in Panggung Lor village is a high settlement risk building structure. This is caused by lithological estuary region consisting predominantly of fine clay-sized sediments with a low level of consistency. The low value of consistency is comparable to the soil bearing capacity value of the water structure foundation pillars. Analysis of the Semarang river Gate House cone penetration test results aims to determine the increase of soil bearing capacity with the method of grouting on the site by using the cone penetration test results. From the three trial soil penetration test location before the grouting process, the very soft clay was found in the 0,6 to 15 metres in depth with 1 up to 4 kg/cm2 of cones resistance value. For deepness 14,00 m - 20,00 m there are soft clay with cones resistance value ( qc) 5 - 8 kg / cm2.. The determining processes of soil bearing capacity then consist of several processes. Based on this, the ultimate bearing capacity mean value before the grout process is about 19,45 with the allowable bearing capacity mean value about 3,97 ton. The ultimate bearing capacity mean value after the grout is about 38,557 ton with the allowable bearing capacity mean value 7,8625 ton. It appears that the increase of ultimate bearing capacity is about 98 % or about 1,9 times greater than before. Keywords : soil bearing capacity, very soft soil, grouting, stable soi

Machine learning for energy efficiency - Automatic detection of electric loads from power consumption

This work deals with the problem of energy efficiency and saving: we present a method to automatically extract behavioral rules from consumption data, so that these rules can be applied or fed to an automatic control system. To extract behavioral rules we shall be able to both (i) define power plants similarity techniques and (ii) analyze and gather rules from data, making the correct assumptions