4 research outputs found

    Avaliação do desempenho de novos serviços em redes IP

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    Mestrado em Engenharia Electrónica e TelecomunicaçõesOs benefícios económicos de fornecer múltiplos serviços numa única rede têm despertado grande interesse na introdução dos serviços VoIP e IPTV na internet. No entanto, estes serviços possuem requisitos rigorosos de qualidade de serviço, que a internet não está preparada para fornecer. Esta dissertação possui dois objectivos principais: O primeiro consiste em testar o comportamento dos serviços de IPTV e VoIP nas tecnologias IP existentes como Ethernet, IEEE 802.11 e ADSL quando expostas a diferentes condições de carga. Pretende-se também identificar os efeitos nos serviços de VoIP e IPTV de outros serviços como FTP, correio electrónico e HTTP. Foi utilizado OpNet um simulador de redes bastante popular ao no ambiente académico. Os resultados das simulações fornecem orientações importantes sobre a capacidade máxima de cada tecnologia tendo em conta os requisitos de qualidade de serviço; por outro lado identificam os serviços mais destrutivos para IPTV e VoIP. O segundo objectivo é a implementação de um modelo que permite a monitorização dos serviços de VoIP e IPTV, analisa os indicadores de desempenho reunidos e grava esses indicadores numa base de dados. Todo este processo será efectuado em tempo real com o objectivo de manter a base de dados actualizada. Os resultados disponibilizados por esta estrutura permitem uma melhor gestão da rede, os prestadores de serviços podem ter informações actualizadas sobre o desempenho dos seus serviços, consequentemente é possível identificar uma falha ou uma tendência futura. ABSTRACT: The economical benefits of providing multiple services over a single network infrastructure have spawned great interest in the introduction of new services, such VoIP and IPTV, in the Internet. However, these services have stringent Quality of Service requirements that the Internet was not designed to meet. This dissertation has two main objectives: The first objective is to test the behavior of IPTV and VoIP services in the existing IP network technologies such as Ethernet, IEEE 802.11 and ADSL when exposed to different load conditions; and identify the effects of other services such as FTP, Email and HTTP in VoIP and IPTV demands. In our work we use OpNet, a popular network simulator in the academic environment. The simulation results provide important guidelines about the maximum capacity of each technology keeping in mind QoS requirements; on the other hand, they enable identification of the most damaging services for VoIP and IPTV. The second objective is the implementation of a framework that allows monitoring VoIP and IPTV services, analyzing the collected performance measurements, and storing them in a database; all these processes will be performed in real time in order to keep the database up to date. The results available by this framework allow a better network management, the service providers can have current information about their services performance, and consequently it is possible to identify a failure or a future trend

    EWDY: uma plataforma online para planeamento de viagens

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    Trabalho de Projecto apresentado para cumprimento dos requisitos necessários à obtenção do grau de Mestre em Novos Media e Práticas WebEste Trabalho de Projecto consistiu em criar uma plataforma online inserida no conceito de Web 2.0. Destina‐se aos viajantes que procuram planear e gerir as suas viagens de forma mais consciente. O objectivo é facilitar o auto‐conhecimento e desenvolvimento pessoal que o viajante adquire quando viaja. Este projecto tem por base a Teoria do U de Otto Scharmer. É um processo criativo e de liderança, que proporciona o auto‐conhecimento e procura despertar a força de vontade e a criatividade. Melhora a performance do individuo e dos membros de uma organização. A plataforma online foi desenvolvida utilizando as linguagens de programação HTML, CSS, PHP, MySQL, JavaScript e Ajax. Foram tidos em consideração o Design, a Usabilidade e a Arquitectura de Informação de forma a conseguir‐se que um resultado final de fácil utilização. Teve‐se, ainda, em conta os princípios da gamification para criar o processo lógico de utilização baseado na Teoria do U

    Global variation in postoperative mortality and complications after cancer surgery: a multicentre, prospective cohort study in 82 countries

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    © 2021 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY-NC-ND 4.0 licenseBackground: 80% of individuals with cancer will require a surgical procedure, yet little comparative data exist on early outcomes in low-income and middle-income countries (LMICs). We compared postoperative outcomes in breast, colorectal, and gastric cancer surgery in hospitals worldwide, focusing on the effect of disease stage and complications on postoperative mortality. Methods: This was a multicentre, international prospective cohort study of consecutive adult patients undergoing surgery for primary breast, colorectal, or gastric cancer requiring a skin incision done under general or neuraxial anaesthesia. The primary outcome was death or major complication within 30 days of surgery. Multilevel logistic regression determined relationships within three-level nested models of patients within hospitals and countries. Hospital-level infrastructure effects were explored with three-way mediation analyses. This study was registered with ClinicalTrials.gov, NCT03471494. Findings: Between April 1, 2018, and Jan 31, 2019, we enrolled 15 958 patients from 428 hospitals in 82 countries (high income 9106 patients, 31 countries; upper-middle income 2721 patients, 23 countries; or lower-middle income 4131 patients, 28 countries). Patients in LMICs presented with more advanced disease compared with patients in high-income countries. 30-day mortality was higher for gastric cancer in low-income or lower-middle-income countries (adjusted odds ratio 3·72, 95% CI 1·70–8·16) and for colorectal cancer in low-income or lower-middle-income countries (4·59, 2·39–8·80) and upper-middle-income countries (2·06, 1·11–3·83). No difference in 30-day mortality was seen in breast cancer. The proportion of patients who died after a major complication was greatest in low-income or lower-middle-income countries (6·15, 3·26–11·59) and upper-middle-income countries (3·89, 2·08–7·29). Postoperative death after complications was partly explained by patient factors (60%) and partly by hospital or country (40%). The absence of consistently available postoperative care facilities was associated with seven to 10 more deaths per 100 major complications in LMICs. Cancer stage alone explained little of the early variation in mortality or postoperative complications. Interpretation: Higher levels of mortality after cancer surgery in LMICs was not fully explained by later presentation of disease. The capacity to rescue patients from surgical complications is a tangible opportunity for meaningful intervention. Early death after cancer surgery might be reduced by policies focusing on strengthening perioperative care systems to detect and intervene in common complications. Funding: National Institute for Health Research Global Health Research Unit

    Effects of hospital facilities on patient outcomes after cancer surgery: an international, prospective, observational study

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    © 2022 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 licenseBackground: Early death after cancer surgery is higher in low-income and middle-income countries (LMICs) compared with in high-income countries, yet the impact of facility characteristics on early postoperative outcomes is unknown. The aim of this study was to examine the association between hospital infrastructure, resource availability, and processes on early outcomes after cancer surgery worldwide. Methods: A multimethods analysis was performed as part of the GlobalSurg 3 study—a multicentre, international, prospective cohort study of patients who had surgery for breast, colorectal, or gastric cancer. The primary outcomes were 30-day mortality and 30-day major complication rates. Potentially beneficial hospital facilities were identified by variable selection to select those associated with 30-day mortality. Adjusted outcomes were determined using generalised estimating equations to account for patient characteristics and country-income group, with population stratification by hospital. Findings: Between April 1, 2018, and April 23, 2019, facility-level data were collected for 9685 patients across 238 hospitals in 66 countries (91 hospitals in 20 high-income countries; 57 hospitals in 19 upper-middle-income countries; and 90 hospitals in 27 low-income to lower-middle-income countries). The availability of five hospital facilities was inversely associated with mortality: ultrasound, CT scanner, critical care unit, opioid analgesia, and oncologist. After adjustment for case-mix and country income group, hospitals with three or fewer of these facilities (62 hospitals, 1294 patients) had higher mortality compared with those with four or five (adjusted odds ratio [OR] 3·85 [95% CI 2·58–5·75]; p<0·0001), with excess mortality predominantly explained by a limited capacity to rescue following the development of major complications (63·0% vs 82·7%; OR 0·35 [0·23–0·53]; p<0·0001). Across LMICs, improvements in hospital facilities would prevent one to three deaths for every 100 patients undergoing surgery for cancer. Interpretation: Hospitals with higher levels of infrastructure and resources have better outcomes after cancer surgery, independent of country income. Without urgent strengthening of hospital infrastructure and resources, the reductions in cancer-associated mortality associated with improved access will not be realised. Funding: National Institute for Health and Care Research
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