4,348 research outputs found
Modeling heterogeneity in random graphs through latent space models: a selective review
We present a selective review on probabilistic modeling of heterogeneity in
random graphs. We focus on latent space models and more particularly on
stochastic block models and their extensions that have undergone major
developments in the last five years
Nine Quick Tips for Analyzing Network Data
These tips provide a quick and concentrated guide for beginners in the
analysis of network data
Implementing Norm-Governed Multi-Agent Systems
The actions and interactions of independently acting agents in a multi-agent system must be managed if the agents are to function effectively in their shared environment. Norms, which define the obligatory, prohibited and permitted actions for an agent to perform, have been suggested as a possible method for regulating the actions of agents.
Norms are local rules designed to govern the actions of individual agents whilst also allowing the agents to achieve a coherent global behaviour. However, there appear to be very few instances of norm-governed multi-agent systems beyond theoretical examples.
We describe an implementation strategy for allowing autonomous agents to take a set of norms into account when determining their actions. These norms are implemented using directives, which are local rules specifying actions for an agent to perform depending on its current state. Agents using directives are implemented in a simulation test bed, called Sinatra. Using Sinatra, we investigate the ability of directives to manage agent actions.
We begin with directives to manage agent interactions. We find that when agents rely on only local rules they will encounter situations where the local rules are unable to achieve the desired global behaviour.
We show how a centralised control mechanism can be used to manage agent interactions that are not successfully handled by directives. Controllers, with a global view of the interaction, instruct the individual agents how to act. We also investigate the use of an existing planning tool to implement the resolution mechanism of a controller.
We investigate the ability of directives to coordinate the actions of agents in order to achieve a global objective more effectively. Finally, we present a case study of how directives can be used to determine the actions of autonomous mobile robots.Open Acces
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New Exploration in the Chitral Valley, Pakistan: An Extension of the Gandharan Grave Culture
NoNew survey in the Chitral Valley has doubled the number of recorded Gandharan Grave culture sites in the region and extended their geographical range. The numbers and location of sites indicates that the Gandharan Grave culture was well established in the Chitral valley, suggesting that the valley may have been central to this cultural development, rather than marginal
Les sans-papiers et l'économie dissimulée
La question des "sans-papiers", des clandestins est souvent considérée, du point de vue du travail, comme équivalent au travail dissimulé or il n'en est rien. Les travailleurs sans-papiers ne représentent qu'une fraction très minoritaire du travail "clandestin". Cet article revient sur ce point au travers de l'analyse de la régularisation opérée à partir de la circulaire du 24 juin 1997
Et si on parlait d'argent?
Les formes de domination des rapports de travail par la forme argent connaît une extension considérable avec le processus actuel de mondialisation de l'économie marchande. Pourtant, dans le cadre de la sociologie du travail, il existe une tendance à la naturalisation du travail en le rabattant sur la catégorie de l'activité. Les théories autour de la fin du travail constituent un aboutissement de ce processus ; elles s'appuient, pour débarrasser la réflexion sur la démocratie politique de la question du travail, sur l'exemple de la Grèce du Vème siècle. Produire la critique de ce courant de la sociologie du travail, suppose de faire retour sur le lien établi, dans la Cité grecque, entre démocratie et travail. À partir de cette critique, il est alors possible de proposer une autre approche pour explorer les transformations du travail en cours
Use of Ovulation Predictor Kits as Adjuncts When Using Fertility Awareness Methods (FAMs): A Pilot Study
Purpose: Difficult clinical signs such as confusing cervical mucus or erratic basal body temperature can make the use of fertility awareness methods (FAMs) difficult in some cases. The goal of this study was to assess the feasibility of using a cheap urinary luteinizing hormone (LH)–surge identification kit as an adjunct to identify the infertile phase after ovulation when facing these scenarios. Methods: The study used a block-allocation, crossover, 2-arm methodology (LH kit/FAM vs FAM only). Comparison of the 2 arms was done with regard to the accuracy of identification (yes/no) of the luteal phase in each cycle as confirmed by serum progesterone concentrations. Results: We recruited 23 Canadian women currently using FAM, aged 18 to 48 years, who have had menstrual cycles 25 to 35 days long for the past 3 months and perceive themselves to have difficulty with identifying the infertile phase after ovulation. LH kits identified 100% of the luteal phases, whereas FAM indentified 87% (statistically significant). In those identified cycles, LH kits provided a mean of 10.3 days of infertility, and FAM only provided 10 days of infertility (not statistically significant). Conclusions: Among this population, LH kits may offer an adjunct for women who may wish to have an additional double-check. However, there are still clinical circumstances when even an LH kit does not provide confirmation. More research in this area is encouraged
Functional Outcomes of the Low Vision Depression Prevention Trial in Age-Related Macular Degeneration.
Purpose: To compare the efficacy of behavioral activation (BA) plus low vision rehabilitation with an occupational therapist (OT-LVR) with supportive therapy (ST) on visual function in patients with age-related macular degeneration (AMD).
Methods: Single-masked, attention-controlled, randomized clinical trial with AMD patients with subsyndromal depressive symptoms (n = 188). All subjects had two outpatient low vision rehabilitation optometry visits, then were randomized to in-home BA + OT-LVR or ST. Behavioral activation is a structured behavioral treatment aiming to increase adaptive behaviors and achieve valued goals. Supportive therapy is a nondirective, psychological treatment that provides emotional support and controls for attention. Functional vision was assessed with the activity inventory (AI) in which participants rate the difficulty level of goals and corresponding tasks. Participants were assessed at baseline and 4 months.
Results: Improvements in functional vision measures were seen in both the BA + OT-LVR and ST groups at the goal level (d = 0.71; d = 0.56 respectively). At the task level, BA + OT-LVR patients showed more improvement in reading, inside-the-home tasks and outside-the-home tasks, when compared to ST patients. The greatest effects were seen in the BA + OT-LVR group in subjects with a visual acuity ≥20/70 (d = 0.360 reading; d = 0.500 inside the home; d = 0.468 outside the home).
Conclusions: Based on the trends of the AI data, we suggest that BA + OT-LVR services, provided by an OT in the patient\u27s home following conventional low vision optometry services, are more effective than conventional optometric low vision services alone for those with mild visual impairment. (ClinicalTrials.gov number, NCT00769015.)
The transgressive that: making the world uncanny.
In this article, we examine how the demonstrative that may be used to notice an event in the world in such a way as to suggest it has highly unusual or transgressive properties and in so doing invite others to align with that implicit claim. Drawing on Freud's notion of the uncanny, we examine instances of the transgressive that in circumstances in which participants at least entertain the possibility that they are experiencing anomalous or paranormal objects and entities. The analysis outlines the basic features of the transgressive that and examines how it may be the vehicle for a range of delicate interpersonal activities. Throughout the article, we try to show the broader relevance of the analytic argument by reference to data from more mundane interactional settings and to other forms of discourse, including fiction, commentary and interview narrative
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