Analysis methodology for flow-level evaluation of a hybrid mobile-sensor network

Our society uses a large diversity of co-existing wired and wireless networks in order to satisfy its communication needs. A cooper- ation between these networks can benefit performance, service availabil- ity and deployment ease, and leads to the emergence of hybrid networks. This position paper focuses on a hybrid mobile-sensor network identify- ing potential advantages and challenges of its use and defining feasible applications. The main value of the paper, however, is in the proposed analysis approach to evaluate the performance at the mobile network side given the mixed mobile-sensor traffic. The approach combines packet- level analysis with modelling of flow-level behaviour and can be applied for the study of various application scenarios. In this paper we consider two applications with distinct traffic models namely multimedia traffic and best-effort traffic

Uplink packet scheduling in cellular networks with relaying—comparative study

Deployment of intermediate relay nodes in cellular networks, e.g. UMTS/ HSPA, has been proposed for service enhancement, which is of particular importance for uplink users at the cell edge suffering from low power capacity and relatively poor channel conditions. In this paper, we propose and investigate a number of uplink packet scheduling schemes deploying the relay functionality in different ways. Using a combined packet and flow level analysis capturing the specifics of the scheduling schemes and the random behavior of the users (initiation and completion of flow transfers), the performance of the various schemes is evaluated and compared to a reference scenario where relaying is not used. The main performance measures considered in our study are realized data rates and mean flow transfer times. Interestingly, considering flow transfer times, it is found that the use of relay nodes is not only particularly beneficial for users at the cell edge but also has a strong, positive effect on the performance of users at other locations not transmitting via a relay node

Surgical treatment of large angle esotropia

Цел: Да анализираме ефекта от големите симетрични рецесии на вътрешните прави мускули като хирургичен избор при есотропия с голям ъгъл на отклонение.Материали и методи: Проучването включва 200 деца (З70 очи), оперирани за есотропия в периода 2000-2014 от един и същ хирург в една и съща база. Двустранна симетрична рецесия на вътрешните прави мускули бе извършена при 170 (З40 очи), a едностранна рецесия- при ЗО деца с различна форма алтернираща/алтернизирана есотропия. Изчислен бе ефектът коригирани призмени диоптри на всеки мм рецесия (Ымм), като таргетният ъгъл бе определен чрез алтерниращ призмен cover тест или чрез теста на максимална моторна фузия.Резултати: Ефектът Δмм бе право пропорционален на големината на ретропозицията (р<0.001). Само 6% от пациентите бяха оперирани повторно (резекция на външен прав мускул), заради остатъчен ъгъл на отклонение.Заключение: Колкото по-голяма е рецесията на вътрешен прав мускул, толкова по-голям е ефектът на коригирани призмени диоптри на всеки мм ретропозиция. Големите рецесии могат успешно да коригират есотропия с голям ъгъл на отклонение и дават резултат, съизмерим с операции на три или четири мускула.Aim: To evaluate the effect of large medial rectus muscle recessions in the attempt to operate on less muscles in large angle esotropia.Material and methods: This is a retrospective study including 200 children (370 eyes), operated on for esotropia in the period of 2000-2014 by one and the same surgeon. One hundred and seventy of them (340 eyes) underwent bilateral medial rectus muscle recessions and 30 - unilateral medial rectus muscle recession for various forms of alternating esotropia. We evaluated the effect of corrected priam diopters for each mm of recession (Δ/mm recession) and the target angle was determined by alternate prism cover test alone or by maximum motor fusion test.Results: The mean effect corrected prism dioptres for each mm of recession (Δ /mm) was in a direct proportion to the amount of retroplacement (p<0.001). Only 6% of our patients needed a second surgery (a lateral rectus muscle resectipon) for a residual angle.Conclusion: The larger the recession, the bigger the effect of corrected prism dioptres for each mm of retroplacement. Thus large bilateral medial rectus muscle recessions can correct successfully large angle esotropia and give similar results to surgery of three or four muscles

Scheduling strategies for LTE uplink with flow behaviour analysis

Long Term Evolution (LTE) is a cellular technology developed to support\ud diversity of data traffic at potentially high rates. It is foreseen to extend the capacity and improve the performance of current 3G cellular networks. A key\ud mechanism in the LTE traffic handling is the packet scheduler, which is in charge of allocating resources to active flows in both the frequency and time dimension. In this paper we present a performance comparison of two distinct scheduling schemes for LTE uplink (fair fixed assignment and fair work-conserving) taking into account both packet level characteristics and flow level dynamics due to the random user behaviour. For that purpose, we apply a combined analytical/simulation approach which enables fast evaluation of performance measures such as mean flow transfer times manifesting the impact of resource allocation strategies. The results show that the resource allocation strategy has a crucial impact on performance and that some trends are observed only if flow level dynamics are considered

Factors Determining the Underdeveloped Social Interest in Children with Special Needs

Background: Individual psychology regards the development of social interest in a child as a key precondition for the child’s socialization. The low level of social interest is the result of the interplay of various factors, which are the subject of this research.Aim: The aim of this study is to investigate the factors that lead to underdeveloped social interest in children with special needs.Material and Methods: The methods applied in this study are theoretical analysis, observation and diagnosis of the psychomotor development of children with special needs.Results: The results of the study indicate that one of the main factors for the underdevelopment of social interest in children with special needs is the type of disorder they are suffering from – auditory, visual, motor or combined. The diagnosis and observation of the psychomotor development of children with special needs in early childhood, and in particular in children with hearing problems, demonstrate that there are limitations in their communication skills and that the systems responsible for the development of cooperation and mutual aid are blocked.Conclusion: This study demonstrates that one of the main factors determining the delay in the development of social interest and the ensuing problems with the socialization of children with special needs is the sensory or combined disorder the child has been diagnosed with. The primary ways to partially overcome this delay are treatment of the disorders, in particular the auditory ones, complex rehabilitation and application of a set of actions designed to aid in the development of communication skills

Clinical Case of a Child with Optic Neuritis, Associated with Epstein-Barr Virus

We present a clinical case of a child with bilateral papillitis, associated with EBV-infection in a 5-year-old female child, who was diagnosed and treated at the Aleksandrovska University Hospital. The initial reason for the eye-exam was a new-onset squint. On admission, she had discrete Eidon confocal scan, decreased visual acuity and bilateral edema and hyperemia of the optic disks. MRI of brain and orbits was evaluated on emergency to rule out a demyelinating or intracranial process. The child had persistent lymphadenopathy and laboratory abnormalities and tested positive for EBV serology. She was treated with intravenous corticosteroid pulse therapy and visual acuity was restored to 100%. Papillitis in children is frequently bilateral, with viral genesis and has a good prognosis. Isolated papillitis (without inflammation of other eye structures) is difficult to distinguish clinically from papilledema. When papilledema is suspected, urgent MRI has to be carried out

Advances in surface EMG signal simulation with analytical and numerical descriptions of the volume conductor

Surface electromyographic (EMG) signal modeling is important for signal interpretation, testing of processing algorithms, detection system design, and didactic purposes. Various surface EMG signal models have been proposed in the literature. In this study we focus on 1) the proposal of a method for modeling surface EMG signals by either analytical or numerical descriptions of the volume conductor for space-invariant systems, and 2) the development of advanced models of the volume conductor by numerical approaches, accurately describing not only the volume conductor geometry, as mainly done in the past, but also the conductivity tensor of the muscle tissue. For volume conductors that are space-invariant in the direction of source propagation, the surface potentials generated by any source can be computed by one-dimensional convolutions, once the volume conductor transfer function is derived (analytically or numerically). Conversely, more complex volume conductors require a complete numerical approach. In a numerical approach, the conductivity tensor of the muscle tissue should be matched with the fiber orientation. In some cases (e.g., multi-pinnate muscles) accurate description of the conductivity tensor may be very complex. A method for relating the conductivity tensor of the muscle tissue, to be used in a numerical approach, to the curve describing the muscle fibers is presented and applied to representatively investigate a bi-pinnate muscle with rectilinear and curvilinear fibers. The study thus propose an approach for surface EMG signal simulation in space invariant systems as well as new models of the volume conductor using numerical methods

EXAMINATION OF UREAPLASMA UREALYTICUM DISTRIBUTION IN DIFFERENT ECOSYSTEMS OF PATIENTS AND HEALTHY HUMANS

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Operational risk and insurance: a ruin probabilistic reserving approach

A new methodology for financial and insurance operational risk capital estimation is proposed. It is based on using the finite time probability of (non-)ruin as an operational risk measure, within a general risk model. It allows for inhomogeneous operational loss frequency (dependent inter-arrival times) and dependent loss severities which may have any joint discrete or continuous distribution. Under the proposed methodology, operational risk capital assessment is viewed not as a one off exercise, performed at some moment of time, but as dynamic reserving, following a certain risk capital accumulation function. The latter describes the accumulation of risk capital with time and may be any nondecreasing, mpositive real function hHtL. Under these reasonably general assumptions, the probability of mnon-ruin is explicitly expressed using closed form expressions, derived by Ignatov and Kaishev (2000, 2004, 2007) and Ignatov, Kaishev and Krachunov (2001) and by setting it to a high enough preassigned mvalue, say 0.99, it is possible to obtain not just a value for the capital charge but a (dynamic) risk capital accumulation strategy, hHtL. In view of its generality, the proposed methodology is capable of accommodating any (heavy tailed) mdistributions, such as the Generalized Pareto Distribution, the Lognormal distribution the g-and-h mdistribution and the GB2 distribution. Applying this methodology on numerical examples, we demonstrate that dependence in the loss severities may have a dramatic effect on the estimated risk capital. In addition, we show also that one and the same high enough survival probability may be achieved by mdifferent risk capital accumulation strategies one of which may possibly be preferable to accumulating capital just linearly, as has been assumed by Embrechts et al. (2004). The proposed methodology takes into account also the effect of insurance on operational losses, in which case it is proposed to take the probability of joint survival of the financial institution and the insurance provider as a joint operational risk measure. The risk capital allocation strategy is then obtained in such a way that the probability of joint survival is equal to a preassigned high enough value, say 99.9