IEEE 802.16 standard defines the wireless broadband access network technology called WiMAX. WiMAX introduces several interesting advantages, and one of them is the support for QoS at the MAC level. For these purposes, the base station must allocate slots based on some algorithm. We propose a simple, yet efficient, solution for the WiMAX base station that is capable of allocating slots based on the QoS requirements, bandwidth request sizes, and the WiMAX network parameters. To test the proposed solution, we have implemented the WiMAX MAC layer in the NS-2 simulator. Several simulation scenarios are presented that demonstrate how the scheduling solution allocates resources in various cases. Simulation results reveal the proposed scheduling solution is ensures the QoS requirements of all the WiMAX service classes and shares fairly free resources achieving the work-conserving behaviour.

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This study aims at assessing the effects of an early occupational therapy intervention on the cognitive development and the development of attachment patterns in ELBW infants. The intervention, given weekly at home from six months to 12 months, aimed at supporting parent-child interaction and enhancing motor control and coordination. The study population consisted of 100 ELBW infants matched in pairs in accordance to their pre-perinatal risk scores and allocated successively to intervention or non-intervention groups. Cognitive development was assessed with the Bayley Scales at age two and with the WPPSI at age four. Attachment to primary caregiver was assessed with the Preschool Assessment of Attachment (PAA). Cognitive performance was within age norms in both groups at both ages. Intervention did not show any effect on cognitive performance at the age of two years. At the age of four years, cognitive level was overall, and most notably for verbal performance, higher in the intervention group than in the control group. There was an over-representation of the so-called atypical attachment patterns (those not fitting the normative A, B, or C categories) in the control group. The results are discussed in terms of finding more global ways to support the development of at risk pre-term children.

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a b s t r a c tModern web services face an increasing number of new threats. Logs are collected from almost all web servers, and for this reason analyzing them is beneficial when trying to prevent intrusions. Intrusive behavior often differs from the normal web traffic. This paper proposes a framework to find abnormal behavior from these logs. We compare random projection, principal component analysis and diffusion map for anomaly detection. In addition, the framework has online capabilities. The first two methods have intuitive extensions while diffusion map uses the Nyström extension. This fast out-of-sample extension enables real-time analysis of web server traffic. The framework is demonstrated using real-world network log data. Actual abnormalities are found from the dataset and the capabilities of the system are evaluated and discussed. These results are useful when designing next generation intrusion detection systems. The presented approach finds intrusions from high-dimensional datasets in real time.

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