GOSPF: An energy efficient implementation of the OSPF routing protocol

Energy saving iscurrently one of the most challenging issues for the Internet research community. In- deed, the exponential growth of applications and services induces a remarkable increase in power consumption and hence calls for novel solutions which are capable to preserve energy of the infra- structures, at the same time maintaining the required Quality of Service guarantees. In this paper we introduce a new mechanism for saving energy through intelligent switch off of network links. The mechanism has been implemented as an extension to the Open Shortest Path First routing protocol.We first show through simulations that our solutionis capable to dramatically reduce energy consumption when compared to the standard OSPF implementation. We then illustrate a real-world implementation of the proposed protocol within the Quagga routing software suite

Can cooperation improve energy efficiency in ad hoc wireless networks?

To make an ad hoc network work properly, wireless nodes are usually requested to cooperate in routing operations. However, there is currently a lack of behavior-tracking mechanisms, so certain nodes can freely play a selfish role at the detriment of altruistic ones. In this paper we try to answer the question in the title, by showing how cooperation can definitely help reduce the overall energy consumed in an ad hoc network. By exploiting a behavior-tracking algorithm mutuated from game theory, we allow traffic to be forwarded only towards cooperative nodes. We hence prove that we can reduce power wastage at the same time maximizing the delivery rate. With the mentioned approach, selfish nodes are isolated from the network unless they decide to start cooperating. Our experimental tests aim at verifying the quick reaction time in response to variable nodes' behaviors as well as presenting a comparative analysis of the actual energy spent to successfully send traffic towards destinations

A Review of Radioactive Wastes Production and Potential Environmental Releases at Experimental Nuclear Fusion Facilities

The development of experimental nuclear fusion facilities and the systems connected to them currently involves the operation (or advanced design) of some large plants in the national territory. Devices such as neutron generators and plasma focus systems are also included. The machines developed to test the main components of these systems such as neutral beam generators (Neutral Beam Injector) and the experimental plants for thermonuclear fusion, mainly in the Tokamak configuration (toroidal geometry), are in the list. These applications are characterized by high neutron fluxes of high energy (typically 2.5 and 14 MeV from deuterium-deuterium and deuterium-tritium fusion reactions, respectively). They involve the production of radionuclides in the components of the machines and in the fluids used for targets' cooling and in the primary containments. In many cases, the atmosphere of the rooms containing these structures is activated and may be affected by the dispersion of powders that are more or less radioactive. The present work addresses the issues mentioned so far, taking into consideration the real cases relating to the devices and the facilities in operation, under construction, and in the advanced design phase. The conclusions highlight the critical aspects related to the management of these types of waste, as well as the low or very low environmental impact, from a radiological point of view, of the examined facilities

The incidence of hip, forearm, humeral, ankle, and vertebral fragility fractures in Italy: results from a 3-year multicenter study

INTRODUCTION: We aimed to assess the incidence and hospitalization rate of hip and "minor" fragility fractures in the Italian population. METHODS: We carried out a 3-year survey at 10 major Italian emergency departments to evaluate the hospitalization rate of hip, forearm, humeral, ankle, and vertebral fragility fractures in people 45 years or older between 2004 and 2006, both men and women. These data were compared with those recorded in the national hospitalizations database (SDO) to assess the overall incidence of fragility fractures occurring at hip and other sites, including also those events not resulting in hospital admissions. RESULTS: We observed 29,017 fractures across 3 years, with hospitalization rates of 93.0% for hip fractures, 36.3% for humeral fractures, 31.3% for ankle fractures, 22.6% for forearm/wrist fractures, and 27.6% for clinical vertebral fractures. According to the analyses performed with the Italian hospitalization database in year 2006, we estimated an annual incidence of 87,000 hip, 48,000 humeral, 36,000 ankle, 85,000 wrist, and 155,000 vertebral fragility fractures in people aged 45 years or older (thus resulting in almost 410,000 new fractures per year). Clinical vertebral fractures were recorded in 47,000 events per year. CONCLUSIONS: The burden of fragility fractures in the Italian population is very high and calls for effective preventive strategies

Fractionated stereotactic radiotherapy for skull base tumors: analysis of treatment accuracy using a stereotactic mask fixation system

Background: To assess the accuracy of fractionated stereotactic radiotherapy (FSRT) using a stereotactic mask fixation system. Patients and Methods: Sixteen patients treated with FSRT were involved in the study. A commercial stereotactic mask fixation system (BrainLAB AG) was used for patient immobilization. Serial CT scans obtained before and during FSRT were used to assess the accuracy of patient immobilization by comparing the isocenter position. Daily portal imaging were acquired to establish day to day patient position variation. Displacement errors along the different directions were calculated as combination of systematic and random errors. Results: The mean isocenter displacements based on localization and verification CT imaging were 0.1 mm (SD 0.3 mm) in the lateral direction, 0.1 mm (SD 0.4 mm) in the anteroposterior, and 0.3 mm (SD 0.4 mm) in craniocaudal direction. The mean 3D displacement was 0.5 mm (SD 0.4 mm), being maximum 1.4 mm. No significant differences were found during the treatment (P = 0.4). The overall isocenter displacement as calculated by 456 anterior and lateral portal images were 0.3 mm (SD 0.9 mm) in the mediolateral direction, -0.2 mm (SD 1 mm) in the anteroposterior direction, and 0.2 mm (SD 1.1 mm) in the craniocaudal direction. The largest displacement of 2.7 mm was seen in the cranio-caudal direction, with 95% of displacements < 2 mm in any direction. Conclusions: The results indicate that the setup error of the presented mask system evaluated by CT verification scans and portal imaging are minimal. Reproducibility of the isocenter position is in the best range of positioning reproducibility reported for other stereotactic systems

Towards a fairer energy consumption in wireless ad hoc networks

A well known and still open issue of wireless ad hoc networks is the unfair energy consumption among the nodes. The specific position of certain nodes composing an ad hoc network makes them more involved in network operations than others, causing a faster drain of their energy. To better distribute the energy level and increase the lifetime of the whole network, we propose to periodically force the cooperation of less operative nodes while overwhelmed nodes deliberately stop their service. A dedicated ad hoc network routing protocol is introduced to discover alternative paths without losses in the overall network performance

A Cost Effective Solution for the Deployment of Wireless Sensor Networks

The paper presents a framework for the design and implementation of dynamic sensor networks. The focus is on minimizing the costs associated with deploying such networks, while at the same time making available a fully fledged set of functions. This is achieved by leveraging a modular design based on an easily programmable, cost-effective micro-controller that can be interfaced with a set of heterogeneous sensors and wireless technologies. A real-world implementation of the proposed architecture is described. Our preliminary in-field performance measurements show that such a system can manage, with a high degree of precision and in real-time, a sustained rate of data gathered from mobile units

Appunti su alcuni aspetti della testualità antica (secoli XIII-XIV)

Della varia problematica riguardante il rapporto tra la sintassi del periodo e la testualità nella prosa antica (sec. XIV-XVI) sono esaminati, da un punto di vista metodologico e operativo, i seguenti aspetti: 1) il macrotesto e le sue sottounità; 2) rapporti testo - paratesto; 3) qualità dei “testi misti”; 4) la ‘materialità’ del testo; 5) il parlato nello scritto; 6) la tipologia testuale