Publish in OALib Journal

ISSN: 2333-9721

APC: Only $99


Any time

2019 ( 20 )

2018 ( 13 )

2017 ( 5 )

2016 ( 21 )

Custom range...

Search Results: 1 - 10 of 5208 matches for " Carla; "
All listed articles are free for downloading (OA Articles)
Page 1 /5208
Display every page Item
Inter-Network Resource Sharing in IEEE 802.22 Networks  [PDF]
Carla Passiatore, Pietro Camarda
Communications and Network (CN) , 2012, DOI: 10.4236/cn.2012.42015
Abstract: IEEE 802.22 is the first worldwide standard for Cognitive Networks (CNs) that exploits unused spectrum of the television broadcast service. An IEEE 802.22 network is also called Wireless Regional Area Network (WRAN). An open issue in cognitive 802.22 networks is represented by the resource distribution among WRANs. In this paper a protocol for radio resource management for CNs in a multichannel environment is presented and analysed. In particular, the contribution of this work is a resource sharing method to schedule the WRAN access to the available channels in a community made by two o more coexisting WRANs. The method adapts to the continuous changes of the spectrum availability due to necessity of vacating a channel in case of the incumbent primary users. Moreover, the introduced allocation scheme allows to divide the available band in a proportional way to the cognitive user spectrum demands, taking into account the issue of spatial diversity, i.e. the case where the channel coverage area is not uniform. The effectiveness of the proposed multichannel scheme is proved through simulations. The results compared favorably with other methods already known in literature and show that the proposed algorithm optimize the spectral efficiency, keeping high fairness as demonstrated computing the Jain’s index.
Energy and Sustainability in Museums. The Plant Refurbishment of the Medieval Building of Palagio di Parte Guelfa in Florence  [PDF]
Carla Balocco, Enrico Marmonti
Open Journal of Energy Efficiency (OJEE) , 2012, DOI: 10.4236/ojee.2012.13004
Abstract: This paper presents a performance-based design of a HVAC plant and controller system of the “Palagio di Parte Guelfa” Palace, a medieval building converted into a museum in the city of Firenze. Transient simulations to evaluate the internal microclimate conditions during the year for the building and the different system plant were carried out. A comparison between the indoor microclimatic parameters obtained and the values suggested by the standards on protection and conservation of historical works of art, suggested a non-invasive and reversible plant system solution. The MuseumofHistorical Footballbuilding portion is the case study. The proposed plant, a constant air flow system coupled with radiant panels dry mounted above the existing flooring, was simulated throughout the year under transient conditions to evaluate its energy performance. This solution ensures indoor temperature and humidity values suitable for the conservation of works of art and visitor comfort. It is an example of a possible course of action for a plant refurbishment in a historic building converted into a museum, located in climatic regions characterized by high thermal and solar loads. The present paper concerns the study of an integrated and reversible architectural-plant solution proposed: reversibility of the proposed system is understood as the possibility for the present conditions being easily restored.
Apoptosis in TMJ Disc Diseases  [PDF]
Giuseppe Musumeci, Carla Loreto
Open Journal of Apoptosis (OJApo) , 2013, DOI: 10.4236/ojapo.2013.24007
Abstract: Apoptosis in TMJ Disc Diseases
Challenges of Effective Collaboration in a Virtual Learning Environment among Undergraduate Students  [PDF]
Russell Butson, Carla Thomson
Creative Education (CE) , 2014, DOI: 10.4236/ce.2014.516162
Abstract: Web-based technology has influenced the way we perceive and use computer devices. One effect of the increasing variety of online web services has been a move away from “personal” computing toward networked or “social” computing. In this paper we discussed a research project which explored the potential in using a purpose-built social-networked environment to support learning in undergraduate education. In particular, we were interested in which tools would be adopted and the collaborative manner which would be used. A prototype web-based networked environment was built that allowed each student a personal space with their profile, access to resources and a group-project work space. The network incorporated a people-centric paradigm that integrated networking across a range of collaborative tools to support course activities. The system embraced an “open” philosophy where all students and staff were linked to all members and work- group areas. Each work-group area consisted of a number of web-based tools that included a group wiki, group blog, file repository, weblink tool, discussion area, and calendar. The site allowed for both synchronized and asynchronized communication via messaging and chat facilities. The results showed that students did not work collaboratively and struggled to use the web-based tools to advance their learning. Further investigation revealed that students preferred individual offline approaches to the more demanding processes required in a collaborative online environment.
Modelling infection spreading control in a hospital isolation room  [PDF]
Carla Balocco, Pietro Liò
Journal of Biomedical Science and Engineering (JBiSE) , 2010, DOI: 10.4236/jbise.2010.37089
Abstract: This paper investigates the airflow patterns connected to different cough conditions, the effects of these arrangements on the regions of droplet fallout and dilution time of virus diffusion of coughed gas. We focus on some of the physical processes that occur in a double bed hospital isolation room, investigating the effect of the ventilation system on the spread of particles in air. A cough model was carried out and used for the numerical simulation of virus diffusion inside an existent isolation room. Transient simulations of air pattern diffusion and air velocity field, provided by the existing typical HVAC primary air system designed for infectious patients, were performed using CFD. A multiphysics approach, combined Convection-Conduction, Incompressible Navier-Stokes models on non-isothermal air flow and Convection-Diffusion, was used. Simulations results highlighted that the flow field and velocity distribution induced by the high turbulence air inlet diffuser combined with the air return diffusers produce wide recirculation zones near the wall and partial stagnation areas near the ceiling and between the two beds, but lower particle concentration in the room and their shorter spreading distance. This type of analysis is certainly cost effective to identify all the air recirculation zones which can harbour lingering pathogens.
Mapping Glitches of Juniper Forests in Lebanon under Natural Conditions and Anthropogenic Activities  [PDF]
Ihab Jomaa, Carla Khater
Open Journal of Forestry (OJF) , 2019, DOI: 10.4236/ojf.2019.92008
Abstract: In 1965, the first forest map of Lebanon was produced. It is the oldest spatial distribution representation of junipers. Landcover maps of 2002 and 2010 are the most detailed spatial distribution that spatially shows forests. Juniper forests are found in Lebanon as mainly as clear to low density coverage. High-density juniper forests are rarely found and only on Mount-Lebanon. Juniper forests are also mixed with oaks on the Eastern flank of Mount-Lebanon. Mapping juniper forests have demonstrated high degree of complexity, especially because of their low density and being mixed. The spatial representation of juniper forests was compared between the 1965 forest map and the landcover maps of 2002 and 2010. GIS environment was used to extract juniper forests from all maps. The degree of matching between juniper forests was investigated regarding the total area and spatial overlapping. Juniper forests were examined to their spatial locations, comparing the three maps. Spatial changes and anthropogenic effect were obtained, using Google Earth facilities. Google earth had satellite images acquired since 2014. Landcover maps of 2002 and 2010 have spatially matched forest map of 1965 by about 90% and 50% respectively. Spatial coverage of juniper forests were about 12,000, 26,000 and 28,000 ha on the 1965 forest map, landcover maps of 2003 and 2010 respectively. Anti-Lebanon juniper forests were not well represented on both landcover maps. Anthropogenic activities were mainly agriculture that affected juniper forests. Cultivations have replaced about 2% of the spatial coverage of 1965 Juniper forests. Quarries and urban existed inside juniper forests but in very limited areas. Juniper forests delineation did not completely match neither between the available maps, nor to the ground. Some juniper forests were not spatially represented on all maps or existing maps represented only portion of juniper forests. Juniper forest mapping requires more consideration and field investigation. High spatial resolution satellite images are among the solutions but delimiting juniper would require extensive fieldwork and specific remote sensing treatments. Being centuries old forests and characterized by High Mountain elevations, these important conifer forests are needed to be mapped with higher accuracy for better statistics and conservation.
A parar el match: política, deporte y arte
Revista de Estudios Sociales , 2009,
Abstract: this essay explores the relations between representation and politics that arose in conjunction with the davis cup celebrated in bastad, sweden, in 1975, an event that served as a frame for the crossing of contending ideologies and visual images. during the event, the norwegian artist kjartan slettemark produced a poster that encouraged people to stop the tennis matches in protest against the chilean military regime and which, as part of a larger visual and written polemic, culminated with chile's defeat in the matches. this essay delves into the ways a sports competition was transformed into a cultural and political event in which concepts such as the nation and ideologies were disputed. analyzing different discourses and images reproduced in the media, the tensions underlining the sociopolitical ambience of the epoch, which were triggered by the matches, will be traced.
Tuberculosis incidence in Portugal: spatiotemporal clustering
Carla Nunes
International Journal of Health Geographics , 2007, DOI: 10.1186/1476-072x-6-30
Abstract: Continental Portugal is organized in 18 districts with 278 sub-districts. For this case study, the number of new notified cases of TB, per sub-district and per year (2000–2004) was available. TB incidence presents clear spatial patterns: a semivariogram consistent with 40% of nugget effect and 60% of spatial contribution, following an exponential model with a range of 143 kilometres. Temporal semivariograms were not conclusive, as only 5 years of data were available. The spatial and temporal persistence of clusters were analyzed considering different models. Significant high incidence rate space-time clusters were identified in three areas of Portugal (between 2000 and 2004) and a purely temporal cluster was identified covering the whole country, during 2002.In terms of spatiotemporal clustering of tuberculosis disease, the proposed methodology allowed the identification of critical spatiotemporal areas. In Portugal there were 3 critical districts (Porto, Setúbal and Lisbon) with high rates of notified incidences between 2000 and 2004. In methodological terms, semivariogram parameters were successfully applied to define spatiotemporal scan window sizes and shapes (ellipsoidal cylinders), showing very good results and performances in the case study. After defining the clusters, these were authenticated through a validation method, based on geostatistical simulations.In 1993, the World Health Organization (WHO) declared tuberculosis (TB) to be a global emergency. Disease control is based on effective diagnosis, treatment and monitoring of TB cases, and must undergo a directly observed short course therapy [1]; this defines "DOTS strategy". Some authors sustain that tuberculosis can be controlled only if appropriate policies are followed and effective clinical and public health management is ensured [2]. New perspectives and ways of addressing TB treatment and control are needed.Disease mapping has a long history [3] and it is not surprising that this method of descrip
Verbal autopsy: who needs it?
Carla AbouZahr
Population Health Metrics , 2011, DOI: 10.1186/1478-7954-9-19
Abstract: The "gold standard" is medical certification of cause according to the International Classification of Diseases (ICD) [7]. The WHO verbal autopsy tools are designed to generate causes of death that are "ICD compatible." WHO recommends that mortality data derived from verbal autopsy be tabulated separately from data derived using medical certification and ICD coding [7].While verbal autopsy may not be as reliable as hospital-based certification for identifying causes of death, it is able to produce information not available from a medical certificate. Alongside questions about signs and symptoms in the deceased person, verbal autopsy can ask about risk factors and health care seeking prior to death, elucidating social, economic, behavioral, and health system issues that may have contributed to death. This contextual knowledge is invaluable to health care managers and planners. Potential users of data generated through verbal autopsy include communities, health care planners and managers, researchers, global decision-makers, and donors [8]. While there is a degree of overlap, these users have different perspectives on the uses of mortality data. These in turn have an impact on the desirable characteristics of data collection instruments. Researchers, epidemiologists, and global-level decision-makers want mortality data to inform burden of disease estimation and program evaluation. Cause of death estimates must be scientifically validated, meet high standards of accuracy, and be comparable over time and across countries. Uncertainty in cause-specific mortality fractions can be managed.National/subnational decision-makers and health system managers want cause of death data for planning, budgeting, and resource allocation and for monitoring and reporting to donors. The ability to track trends over time is more important than cross-country comparability. Uncertainty is problematic, especially when data are needed to inform allocation of resources. Data need to be actionab
Dise?o urbano para áreas devastadas
ARQ (Santiago) , 2005, DOI: 10.4067/S0717-69962005006000012
Abstract: much of the relationship among citizens is sustained by public works (in terms of transport, communication and exchange), and they can also resolve the relationship between the city and its location. ever less a matter of domination, the relationship should become a kind of dialogue, structured by roads, ditches, canals and drains.
Page 1 /5208
Display every page Item

Copyright © 2008-2017 Open Access Library. All rights reserved.