A Decision-Theoretic Approach to Resource Allocation in Wireless Multimedia Networks

The allocation of scarce spectral resources to support as many user applications as possible while maintaining reasonable quality of service is a fundamental problem in wireless communication. We argue that the problem is best formulated in terms of decision theory. We propose a scheme that takes decision-theoretic concerns (like preferences) into account and discuss the difficulties and subtleties involved in applying standard techniques from the theory of Markov Decision Processes (MDPs) in constructing an algorithm that is decision-theoretically optimal. As an example of the proposed framework, we construct such an algorithm under some simplifying assumptions. Additionally, we present analysis and simulation results that show that our algorithm meets its design goals. Finally, we investigate how far from optimal one well-known heuristic is. The main contribution of our results is in providing insight and guidance for the design of near-optimal admission-control policies.Comment: To appear, Dial M for Mobility, 200

Analysis of roles and groups in blogosphere

In the paper different roles of users in social media, taking into consideration their strength of influence and different degrees of cooperativeness, are introduced. Such identified roles are used for the analysis of characteristics of groups of strongly connected entities. The different classes of groups, considering the distribution of roles of users belonging to them, are presented and discussed.Comment: 8th International Conference on Computer Recognition Systems, CORES 201

Automatic method for the dermatological diagnosis of selected hand skin features in hyperspectral imaging

Introduction: Hyperspectral imaging has been used in dermatology for many years. The enrichment of hyperspectral imaging with image analysis broadens considerably the possibility of reproducible, quantitative evaluation of, for example, melanin and haemoglobin at any location in the patient's skin. The dedicated image analysis method proposed by the authors enables to automatically perform this type of measurement. Material and method: As part of the study, an algorithm for the analysis of hyperspectral images of healthy human skin acquired with the use of the Specim camera was proposed. Images were collected from the dorsal side of the hand. The frequency λ of the data obtained ranged from 397 to 1030 nm. A total of 4'000 2D images were obtained for 5 hyperspectral images. The method proposed in the paper uses dedicated image analysis based on human anthropometric data, mathematical morphology, median filtration, normalization and others. The algorithm was implemented in Matlab and C programs and is used in practice. Results: The algorithm of image analysis and processing proposed by the authors enables segmentation of any region of the hand (fingers, wrist) in a reproducible manner. In addition, the method allows to quantify the frequency content in different regions of interest which are determined automatically. Owing to this, it is possible to perform analyses for melanin in the frequency range λE∈(450,600) nm and for haemoglobin in the range λH∈(397,500) nm extending into the ultraviolet for the type of camera used. In these ranges, there are 189 images for melanin and 126 images for haemoglobin. For six areas of the left and right sides of the little finger (digitus minimus manus), the mean values of melanin and haemoglobin content were 17% and 15% respectively compared to the pattern. Conclusions: The obtained results confirmed the usefulness of the proposed new method of image analysis and processing in dermatology of the hand as it enables reproducible, quantitative assessment of any fragment of this body part. Each image in a sequence was analysed in this way in no more than 100 ms using Intel Core i5 CPU M460 @2.5 GHz 4 GB RAM

Marginal zone B cells emerge as a critical component of pregnancy well-being

The success of eutherian mammal evolution was certainly supported by the ability of the already existing immune system to adapt to the presence of the semi-allogeneic fetus without losing the capability to defend the mother against infections. This required the acquisition of highly regulated and coordinated immunological mechanisms. Failures in the development of these strategies not only lead to the interruption of pregnancy but also compromise maternal health. Alongside changes on the cytokine profile - expansion of tolerogenic dendritic and regulatory T cells - a profound adaptation of the B cell compartment during pregnancy was recently described. Among others, the suppression of B cell lymphopoiesis and B cell lymphopenia were proposed to be protective mechanisms tending to reduce the occurrence of autoreactive B cells that might recognize fetal structures and put pregnancy on risk. On the other hand, expansion of the pre-activated marginal zone (MZ) B cell phenotype was described as a compensatory strategy launched to overcome B cell lymphopenia thus ensuring a proper defense. In this work, using an animal model of pregnancy disturbances, we demonstrated that the suppression of B cell lymphopoiesis as well as splenic B cell lymphopenia occur independently of pregnancy outcome. However, only animals undergoing normal pregnancies, but not those suffering from pregnancy disturbances, could induce an expansion and activation of the MZ B cells. Hence, our results clearly show that MZ B cells, probably due to the production of natural protective antibodies, participate in the fine balance of immune activation required for pregnancy well-being.Fil: Muzzio, Damián Oscar. University of Greifswald; AlemaniaFil: Ziegler, Katharina B.. University of Greifswald; AlemaniaFil: Ehrhardt, Jens. University of Greifswald; AlemaniaFil: Zygmunt, Marek. University of Greifswald; AlemaniaFil: Jensen, Cristian Federico. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Centro de Estudios Farmacológicos y Botánicos. Universidad de Buenos Aires. Facultad de Medicina. Centro de Estudios Farmacológicos y Botánicos; Argentina. University of Greifswald; Alemania. Universidad Nacional Arturo Jauretche; Argentin

Higher-order scalar interactions and SM vacuum stability

Investigation of the structure of the Standard Model effective potential at very large field strengths opens a window towards new phenomena and can reveal properties of the UV completion of the SM. The map of the lifetimes of the vacua of the SM enhanced by nonrenormalizable scalar couplings has been compiled to show how new interactions modify stability of the electroweak vacuum. Whereas it is possible to stabilize the SM by adding Planck scale suppressed interactions and taking into account running of the new couplings, the generic effect is shortening the lifetime and hence further destabilisation of the SM electroweak vacuum. These findings have been illustrated with phase diagrams of modified SM-like models. It has been demonstrated that stabilisation can be achieved by lowering the suppression scale of higher order operators while picking up such combinations of new couplings, which do not deepen the new minima of the potential. Our results show the dependence of the lifetime of the electroweak minimum on the magnitude of the new couplings, including cases with very small couplings (which means very large effective suppression scale) and couplings vastly different in magnitude (which corresponds to two different suppression scales).Comment: plain Latex, 9 figure

Different Approaches to Community Evolution Prediction in Blogosphere

Predicting the future direction of community evolution is a problem with high theoretical and practical significance. It allows to determine which characteristics describing communities have importance from the point of view of their future behaviour. Knowledge about the probable future career of the community aids in the decision concerning investing in contact with members of a given community and carrying out actions to achieve a key position in it. It also allows to determine effective ways of forming opinions or to protect group participants against such activities. In the paper, a new approach to group identification and prediction of future events is presented together with the comparison to existing method. Performed experiments prove a high quality of prediction results. Comparison to previous studies shows that using many measures to describe the group profile, and in consequence as a classifier input, can improve predictions.Comment: SNAA2013 at ASONAM2013 IEEE Computer Societ

Spontaneous polarisation of the neutral interface for valence asymmetric coulombic systems

In this paper, we discuss the phenomenon of a spontaneous polarisation of a neutral hard planar interface for valence asymmetric coulombic systems. Within a field theoretical description, we account for the existence of non trivial charge density and electric potential profiles. The analysis of the phenomenon shows that the effect is related to combinatorics in relation with the existence of the two independent species cations and anions. This simple and basic feature is related to the quantum mechanical properties of the system. The theoretical results are compared with numerical simulations data and are shown to be in very good agreement, which a fortiori justifies our physical interpretation.Comment: 12 pages, 11 figure