1,094 research outputs found
Hybrid approach for localization in anisotropic sensor networks
In many real-world applications including agricultural, meterological, military applications, etc, localization techniques are widely used to estimate the geographic locations of sensor nodes based on the precision positions of a few anchors equipped with special hardware. Existing localization algorithms mainly try to improve their accuracy in position estimation by using various heuristic-based or mathematical techniques. Every node in the network follows the same technique to find its physical location. However, each individual method with its own strength can only outperform the others in some but not all nodes. Based on this observation, we develop a hybrid approach for the localization problem. Each node collects the same kind of information. By analysing the information, a node can decide what is the best localization algorithm to use. Different nodes can make their own decisions. Our simulation results reveal that the hybrid approach is effective that it outpeforms existing algorithms. To the best of our knowledge, our work presents the first effort in solving the absolute localization problem by adopting a hybrid approach. © 2006 IEEE.published_or_final_versio
Impact of information presentation modes on online shopping: An empirical evaluation of a broadband interactive shopping service
With the increasing cost-effectiveness of communication technologies, online shopping has emerged as one of the most important areas of electronic commerce. A major problem facing online shopping service providers is the heterogeneity of user profile. Unlike organizational systems that have a well-defined universe of users and system boundary, these shopping services are designed for public users with very different cognitive and demographic profiles. The major challenge lies in designing friendly and effective user interfaces for online shoppers. Previous studies on online shopping suggest that a good user interface with an appropriate mode of information presentation is the key to system acceptance. In this article, we report on an empirical study that looks at product information presentation modes in an actual broadband supermarket shopping environment. Four prototypes with different combinations of text and picture displays were developed and evaluated in an experimental setting. The findings suggest that there is a close relation between product familiarity and shopping effectiveness. When the system is used to purchase familiar product items, pictures are better than text in terms of both efficiency and effectiveness. However, when users are not familiar with the product items, the advantages of pictures over text diminish. Implications of the findings and future research areas are discussed.published_or_final_versio
Improving localization in wireless sensor networks with an evolutionary algorithm
Wireless sensor networks are highly useful for many location-sensitive applications including environmental monitoring, military applications, disaster management, etc. Localization in wireless sensor networks concerns about the precise estimation of node positions given a relatively small portion as anchor nodes with their absolute positions predetermined. Intrinsically, localization is an unconstrained optimization problem based on various distance/path measures. Most of the existing work focus on increasing the accuracy in position estimation typically by using different heuristic-based or mathematical techniques. On the other hand, there were many complex optimization problems successfully tackled by the nature inspired search algorithms including the ant-based or genetic algorithms. In this paper, we propose to adapt an evolutionary approach, namely a microgenetic algorithm, and integrate as a post-optimizer into some existing localization techniques such as the Ad-hoc Positioning System (APS) to further improve their position estimation. Clearly, our proposed MGA is so adaptable that it can easily be integrated into other localization methods. More importantly, the remarkable improvements obtained by the prototype of our proposed evolutionary optimizer on certain anisotropic topologies of our simulation tests prompt for further investigation. © 2006 IEEE.published_or_final_versio
Current concepts in the management of endometrial carcinoma
published_or_final_versio
Front stability of infinitely steep travelling waves in population biology
Reaction-diffusion models are often used to describe biological invasion,
where populations of individuals that undergo random motility and proliferation
lead to moving fronts. Many models of biological invasion are extensions of the
Fisher-KPP model that describes the evolution of a 1D population density as a
result of linear diffusion and logistic growth. In 2020 Fadai introduced a new
model of biological invasion that was formulated as a moving boundary problem
with a nonlinear degenerate diffusive flux. Fadai's model leads to travelling
wave solutions with infinitely steep, well-defined fronts at the moving
boundary, and the model has the mathematical advantage of being analytically
tractable in certain parameter limits. We aim to provide general insight by
first presenting two key extensions by considering: (i) generalised nonlinear
degenerate diffusion with flux; and, (ii) solutions describing both biological
invasion, and biological recession. We establish the existence of travelling
wave solutions for these two extensions, and then consider stability of the
travelling wave solutions by introducing a lateral perturbation of the
travelling wavefront. Full 2D time-dependent level-set numerical solutions
indicate that invasive travelling waves are stable to small lateral
perturbations, whereas receding travelling waves are unstable. These
preliminary numerical observations are corroborated through a linear stability
analysis that gives more formal insight into short time growth/decay of
wavefront perturbation amplitude.Comment: 8 Figures, 25 page
Herpetic shoulder paresis in a Chinese elderly patient
A patient with left shoulder girdle weakness secondary to herpetic myotomal paresis is reported. Needle electromyography revealed denervational discharge from the left supraspinatus, deltoid, and brachioradialis muscles, compatible with a radiculopathy that was relevant to his myotomes affected by zoster infection. The patient was managed with range-of-movement and strengthening exercises as well as pain relief for post-herpetic neuralgia. Further studies are required to determine whether antiviral treatment can limit the extent of motor deficit and hasten recovery. Zoster paresis should be one of the differential diagnoses of girdle muscle weakness.published_or_final_versio
Does more working women result in more single men?
The following report is going to discuss whether the relationship in the title exists. The theoretical approach suggests that both possibilities can happen due to the simple assumptions of the economic theories used in this research. Evidence shows a clear trend for a positive relationship between women’s working hours and the number of single men. However, the trend weakens over the time, possibly due to stabilisation of women’s wages more recently
Survival, extinction, and interface stability in a two--phase moving boundary model of biological invasion
We consider a moving boundary mathematical model of biological invasion. The
model describes the spatiotemporal evolution of two populations: each
population undergoes linear diffusion and logistic growth, and the boundary
between the two populations evolves according to a two--phase Stefan condition.
This mathematical model describes situations where one population invades into
regions occupied by the other population, such as the spreading of a malignant
tumour into surrounding tissues. Full time--dependent numerical solutions are
obtained using a level--set numerical method. We use these numerical solutions
to explore several properties of the model including: (i) survival and
extinction of one population initially surrounded by the other; and (ii) linear
stability of the moving front boundary in the context of a travelling wave
solution subjected to transverse perturbations. Overall, we show that many
features of the well--studied one--phase single population analogue of this
model can be very different in the more realistic two--phase setting. These
results are important because realistic examples of biological invasion involve
interactions between multiple populations and so great care should be taken
when extrapolating predictions from a one--phase single population model to
cases for which multiple populations are present. Open source Julia--based
software is available on GitHub to replicate all results in this study.Comment: 31 pages. 9 figure
Intervenções do enfermeiro especialista em enfermagem de reabilitação no cuidar da pessoa com demência
Os progressos tecnológicos ao nível das ciências da saúde e a melhoria das condições socioeconómicas têm contribuído para o aumento do envelhecimento demográfico e da longevidade da população, à qual se deve uma maior prevalência das doenças crónicas, das quais se destaca, a demência, o que implica à sociedade uma crescente necessidade de cuidados de natureza física, emocional e social. A demência é um problema de saúde pública, cada vez mais evidente na sociedade.
A demência corresponde a uma síndrome de etiologia variada relacionada com processos cerebrais patológicos que afetam a memória, o pensamento, o comportamento e as capacidades funcionais para a realização das atividades de vida diária (AVD). Existem vários tipos de demência, sendo a doença de Alzheimer (DA) a mais comum.
O aumento esperado da demência provocará a necessidade do aumento de cuidados de saúde de enfermagem qualificados, uma vez que existirá maior dependência da pessoa com demência nas AVD. Os dados estatísticos e os estudos desenvolvidos revelam que esta problemática se torna atual e pertinente à intervenção do Enfermeiro Especialista em Enfermagem de Reabilitação (EEER).
Este relatório expõe o percurso de atividades desenvolvidas em contexto de Ensino Clínico (hospitalar e comunitário), tendo como objetivo refletir sobre as intervenções que permitiram o desenvolvimento de competências preconizadas nos descritores de Dublin para o 2º ciclo de ensino para a obtenção do grau de Mestre em articulação com as competências definidas pela Ordem dos Enfermeiros (OE) para a atribuição do título profissional de EEER.
Este trabalho foi dirigido pelo projeto de estágio com o intuito de intervir no cuidar da pessoa com demência. Neste sentido, a abordagem a esta temática mobiliza a Teoria do Défice do Autocuidado de Enfermagem de Orem, sendo este um modelo teórico adequado ao objetivo do trabalho, uma vez que sustenta a relevância de cuidar de pessoas que se encontram dependentes pelo seu estado de saúde. O título do trabalho é “Intervenções do Enfermeiro Especialista em Enfermagem de Reabilitação no Cuidar da Pessoa com Demência”
Primary infective spondylodiscitis caused by Lactococcus garvieae and a review of human L. garvieae infections
We report the first case of primary infective spondylodiscitis due to Lactococcus garvieae, confirmed by 16S rRNA gene sequencing, in the absence of concomitant endocarditis in a patient with long-standing gastritis on famotidine. He responded to a 6-week course of ampicillin. The gastrointestinal tract is probably the source of infection. © 2011 The Author(s).published_or_final_versionSpringer Open Choice, 21 Feb 201
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