903 resultados para Information theory.
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In this paper we use concepts from graph theory and cellular biology represented as ontologies, to carry out semantic mining tasks on signaling pathway networks. Specifically, the paper describes the semantic enrichment of signaling pathway networks. A cell signaling network describes the basic cellular activities and their interactions. The main contribution of this paper is in the signaling pathway research area, it proposes a new technique to analyze and understand how changes in these networks may affect the transmission and flow of information, which produce diseases such as cancer and diabetes. Our approach is based on three concepts from graph theory (modularity, clustering and centrality) frequently used on social networks analysis. Our approach consists into two phases: the first uses the graph theory concepts to determine the cellular groups in the network, which we will call them communities; the second uses ontologies for the semantic enrichment of the cellular communities. The measures used from the graph theory allow us to determine the set of cells that are close (for example, in a disease), and the main cells in each community. We analyze our approach in two cases: TGF-β and the Alzheimer Disease.
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The analysis of system calls is one method employed by anomaly detection systems to recognise malicious code execution. Similarities can be drawn between this process and the behaviour of certain cells belonging to the human immune system, and can be applied to construct an artificial immune system. A recently developed hypothesis in immunology, the Danger Theory, states that our immune system responds to the presence of intruders through sensing molecules belonging to those invaders, plus signals generated by the host indicating danger and damage. We propose the incorporation of this concept into a responsive intrusion detection system, where behavioural information of the system and running processes is combined with information regarding individual system calls.
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Thesis compiles findings from previous research to produce guidelines on addressing crises on social media. These guidelines extracted from previous research are compared qualitatively with empirical evidence from 12 organizations by examining whether organizations apply practices recommended in previous research. Much of guidelines gain support from practitioners with few exceptions. Findings stemming from theory and practice combine to shed light on how controversies are born on social media, how crises can be prevented on social media and how organizations may manage crisis situations on social media. The majority of the resulting guidelines focus on how to address negative information and communicate during a crisis but other means of crisis management are also presented. Previous research had voiced that the field of public relations was very fractured, crisis management was lacking qualitative research and provided very little information on what organizations should do before a crisis. Thesis collects a comprehensive amount of previous research from various fields of PR in an effort to unite findings and guidelines, gathers and analyzes empirical data in a qualitative manner and includes a pre-crisis paradigm. One of the challenges in the field of crisis management still remains the absence of universally agreed definition of a crisis and the lack of means to quantify and compare the magnitude of crises.
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Background: Despite a number of programs aimed at the transfer of reproductive health information, adolescents in Zimbabwe still face unprecedented reproductive challenges. Objectives: The study sought to explore adolescent girls’ knowledge of their sexual and reproductive health; the factors that influence their sexual behaviors and to determine the extent to which adolescents had access to sexual and reproductive health information. Methods: The case study methodology was used for the study. The interpretive paradigm was used as the methodological theory and Grunig’s model of excellence in communication was used as the substantive theory. Data was obtained through the use of focus group discussions and indepth interviews. Results: Although adolescents knew the different types of sexually transmitted diseases and were aware of the consequences of engaging in risky sexual behaviors, they engaged in health behaviors which had potential for serious consequences. The study established that adolescents did not have adequate access to sexual and reproductive health information. Sexual issues were not adequately addressed both at school and at home. Conclusion: Adolescents lack adequate access to reproductive health information and there is need for effective communication programs that contribute towards the understanding of communicated messages by audiences and the understanding of audiences by communicators.
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During "The reader and their information needs" students tried to implement the theory discussed in class. To this end, organized into sub-groups and worked in different types of libraries. The following paper covers the practice that the students: Jenssy Arguedas Salazar Hernández Sandoval Lidiette Oses and Olga Corrales held in the Library "Sister Onorina Leporati" Help Ma College of Alajuela.
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While a variety of crisis types loom as real risks for organizations and communities, and the media landscape continues to evolve, research is needed to help explain and predict how people respond to various kinds of crisis and disaster information. For example, despite the rising prevalence of digital and mobile media centered on still and moving visuals, and stark increases in Americans’ use of visual-based platforms for seeking and sharing disaster information, relatively little is known about how the presence or absence of disaster visuals online might prompt or deter resilience-related feelings, thoughts, and/or behaviors. Yet, with such insights, governmental and other organizational entities as well as communities themselves may best help individuals and communities prepare for, cope with, and recover from adverse events. Thus, this work uses the theoretical lens of the social-mediated crisis communication model (SMCC) coupled with the limited capacity model of motivated mediated message processing (LC4MP) to explore effects of disaster information source and visuals on viewers’ resilience-related responses to an extreme flooding scenario. Results from two experiments are reported. First a preliminary 2 (disaster information source: organization/US National Weather Service vs. news media/USA Today) x 2 (disaster visuals: no visual podcast vs. moving visual video) factorial between-subjects online experiment with a convenience sample of university students probes effects of crisis source and visuals on a variety of cognitive, affective, and behavioral outcomes. A second between-subjects online experiment manipulating still and moving visual pace in online videos (no visual vs. still, slow-pace visual vs. still, medium-pace visual vs. still, fast-pace visual vs. moving, slow-pace visual vs. moving, medium-pace visual vs. moving, fast-pace visual) with a convenience sample recruited from Amazon’s Mechanical Turk (mTurk) similarly probes a variety of potentially resilience-related cognitive, affective, and behavioral outcomes. The role of biological sex as a quasi-experimental variable is also investigated in both studies. Various implications for community resilience and recommendations for risk and disaster communicators are explored. Implications for theory building and future research are also examined. Resulting modifications of the SMCC model (i.e., removing “message strategy” and adding the new category of “message content elements” under organizational considerations) are proposed.
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Background: Ethics is defined as the entirety of moral principles that form the basis of individuals’ behavior; it can also be defined as “moral theory or “theoretical ethics”. Objectives: To determinate information and applications related to ethical codes of pediatric nurses. Patients and Methods: Participants were nurses attending the Neonatal Intensive Care Unit Nursing Course and the Pediatric Nursing Course conducted in Istanbul between September 2011 and December 2012. A total of nurses attending the courses at the specified dates and who agreed to participate in the study were included in the analysis. Data were collected through a questionnaire that we developed in accordance with current literature on nursing ethics. Results: 140 nurses participated in this study. Information and applications were related to ethical codes of nurses including four categories; autonomy, beneficence, nonmaleficence, justice. The principle of confidentiality/keeping secrets. Exactly 64.3% of nurses reported having heard of nursing ethical codes. The best-known ethical code was the principle of justice. Furthermore, while the rates were generally low, some nurses engaged in unethical practices such as patient discrimination and prioritizing acquaintances. Conclusions: We conclude that most nurses working in pediatric clinics act in compliance with ethical codes. We also found that the majority of nurses wanted to learn about ethical codes. For this reason, we recommended that nurses working in clinics and future nurses in training be informed of the appropriate ethical behavior and codes.
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Doutoramento em Economia.
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Œuvre dédiée à Alioune Camara; merci au Prof. Denis Dougnon de l’Université de Bamako pour le parrainage
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This research develops an econometric framework to analyze time series processes with bounds. The framework is general enough that it can incorporate several different kinds of bounding information that constrain continuous-time stochastic processes between discretely-sampled observations. It applies to situations in which the process is known to remain within an interval between observations, by way of either a known constraint or through the observation of extreme realizations of the process. The main statistical technique employs the theory of maximum likelihood estimation. This approach leads to the development of the asymptotic distribution theory for the estimation of the parameters in bounded diffusion models. The results of this analysis present several implications for empirical research. The advantages are realized in the form of efficiency gains, bias reduction and in the flexibility of model specification. A bias arises in the presence of bounding information that is ignored, while it is mitigated within this framework. An efficiency gain arises, in the sense that the statistical methods make use of conditioning information, as revealed by the bounds. Further, the specification of an econometric model can be uncoupled from the restriction to the bounds, leaving the researcher free to model the process near the bound in a way that avoids bias from misspecification. One byproduct of the improvements in model specification is that the more precise model estimation exposes other sources of misspecification. Some processes reveal themselves to be unlikely candidates for a given diffusion model, once the observations are analyzed in combination with the bounding information. A closer inspection of the theoretical foundation behind diffusion models leads to a more general specification of the model. This approach is used to produce a set of algorithms to make the model computationally feasible and more widely applicable. Finally, the modeling framework is applied to a series of interest rates, which, for several years, have been constrained by the lower bound of zero. The estimates from a series of diffusion models suggest a substantial difference in estimation results between models that ignore bounds and the framework that takes bounding information into consideration.
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The conceptual domain of agency theory is one of the dominant organisational theory perspectives applied in current family business research (Chrisman et al., 2010). According to agency theory (Jensen and Meckling, 1976), agency costs generally arise due to individuals’ selfinterest and decision making based on rational thinking and oriented toward own preferences. With more people involved in decision making, such as through the separation of ownership and management, agency costs occur due to different preferences and information asymmetries between the owner (principal) and the employed management (agent) (Jensen and Meckling, 1976). In other words, agents take decisions based on their individual preferences (for example, short term, financial gains) instead of the owners’ preferences (for example, long term, sustainable development).
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Œuvre dédiée à Alioune Camara; merci au Prof. Denis Dougnon de l’Université de Bamako pour le parrainage
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The changes recommended by the New Public Management (NPM) in public accounting have given special attention and importance to the evaluation of mayor’s performance by citizens/voters. Thus, this study aims to assess the impact of accounting information on the re-election of Portuguese mayors. Taking the agency theory as a point of departure, we start from the following research question: Does the accounting information disclosed by the municipalities influence the re-election of Portuguese mayors? The research methodology used in this study is the quantitative type, through which a multivariate analysis of data was performed on 308 Portuguese municipalities, in the period 2005-2008, based on the election results of 2009. The results from the binary logistic regression show that some indicators of accounting nature have impact on the re-election of mayors in Portugal, namely, the components of financial accounting and municipal revenues.
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In knowledge technology work, as expressed by the scope of this conference, there are a number of communities, each uncovering new methods, theories, and practices. The Library and Information Science (LIS) community is one such community. This community, through tradition and innovation, theories and practice, organizes knowledge and develops knowledge technologies formed by iterative research hewn to the values of equal access and discovery for all. The Information Modeling community is another contributor to knowledge technologies. It concerns itself with the construction of symbolic models that capture the meaning of information and organize it in ways that are computer-based, but human understandable. A recent paper that examines certain assumptions in information modeling builds a bridge between these two communities, offering a forum for a discussion on common aims from a common perspective. In a June 2000 article, Parsons and Wand separate classes from instances in information modeling in order to free instances from what they call the “tyranny” of classes. They attribute a number of problems in information modeling to inherent classification – or the disregard for the fact that instances can be conceptualized independent of any class assignment. By faceting instances from classes, Parsons and Wand strike a sonorous chord with classification theory as understood in LIS. In the practice community and in the publications of LIS, faceted classification has shifted the paradigm of knowledge organization theory in the twentieth century. Here, with the proposal of inherent classification and the resulting layered information modeling, a clear line joins both the LIS classification theory community and the information modeling community. Both communities have their eyes turned toward networked resource discovery, and with this conceptual conjunction a new paradigmatic conversation can take place. Parsons and Wand propose that the layered information model can facilitate schema integration, schema evolution, and interoperability. These three spheres in information modeling have their own connotation, but are not distant from the aims of classification research in LIS. In this new conceptual conjunction, established by Parsons and Ward, information modeling through the layered information model, can expand the horizons of classification theory beyond LIS, promoting a cross-fertilization of ideas on the interoperability of subject access tools like classification schemes, thesauri, taxonomies, and ontologies. This paper examines the common ground between the layered information model and faceted classification, establishing a vocabulary and outlining some common principles. It then turns to the issue of schema and the horizons of conventional classification and the differences between Information Modeling and Library and Information Science. Finally, a framework is proposed that deploys an interpretation of the layered information modeling approach in a knowledge technologies context. In order to design subject access systems that will integrate, evolve and interoperate in a networked environment, knowledge organization specialists must consider a semantic class independence like Parsons and Wand propose for information modeling.
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What theoretical framework can help in building, maintaining and evaluating networked knowledge organization resources? Specifically, what theoretical framework makes sense of the semantic prowess of ontologies and peer-to-peer sys- tems, and by extension aids in their building, maintenance, and evaluation? I posit that a theoretical work that weds both for- mal and associative (structural and interpretive) aspects of knowledge organization systems provides that framework. Here I lay out the terms and the intellectual constructs that serve as the foundation for investigative work into experientialist classifi- cation theory, a theoretical framework of embodied, infrastructural, and reified knowledge organization. I build on the inter- pretive work of scholars in information studies, cognitive semantics, sociology, and science studies. With the terms and the framework in place, I then outline classification theory s critiques of classificatory structures. In order to address these cri- tiques with an experientialist approach an experientialist semantics is offered as a design commitment for an example: metadata in peer-to-peer network knowledge organization structures.