Design and capacity performance analysis of wireless mesh network

Proceedings of: 5th International Conference on Mobile Technology, Applications, and Systems (Mobility 2008), (September 10-12, 2008), Yilan (Taiwan)From the network operator’s point of view, the high CAPEX/OPEX cost resulting from fixed/wired backhaul links can be inhibitive to successful deployment of broadband wireless services. The emerging wireless mesh network (WMN) technology is seen as one of the potential solutions which may reduce wired backhaul dependency through multihop transmission. Despite the advantages, many remain sceptical on WMN’s network capacity and scalability performances particularly when the user density is high. This paper provides an insight on the best possible upper-bound capacity performance of WMN, taking into consideration three key design parameters namely 1) Percentage of wired backhaul points per network, 2) Mesh-to-Access Link-Rate Ratio (R) and 3) Number of radio interfaces per mesh node including hybrid radio options. These design options are compared and contrasted with different deployment densities. The results generally show that the higher the number of backhaul points, the higher the effective access capacity available to mesh node and hence user domain. Increasing the R and the number of radio per mesh node are two alternative means to push up the effective access capacity per mesh node without increasing the number of wired backhaul points. This is most significant in multi radio system where about 80% of the backhaul points can be eliminated with R= 3 in order to maintain effective access capacity close to full rate (Capacity, C=1) per mesh node. It is also found that 50% of the backhaul points can be eliminated with R=2 for all radio options (except for the pure single radio case).European Community's Seventh Framework ProgramThis work was partially funded by the European Commission within the 7th Framework Program in the context of the ICT project CARMEN (Grant Agreement No. 214994) http://www.ict-carmen.eu

A cost sensitiviy analysis for carrier grade wireless mesh networks with tabu optimization

Proceedings of: CARMEN 2010: 2nd International Workshop on CARrier-grade wireless MEsh Networks in conjunction with IEEE INFOCOM 2010: IEEE Conference on Computer Communications Workshops: 15-19 March 2010, San Diego, CaliforniaWe present an insight on the sensitivity of total cost (CAPEX+OPEX) towards various key input parameters for CARrier Grade Wireless MEsh Networks (CARMEN) deployment These input parameters span across three main categories namely the network design options, environment conditions and cost. Various boundary conditions are imposed to allow network operator to understand the impacts of parameters'changes with the highest level of uncertainty. A simple Tabu optimization method is adopted to optimize the node density against target data rate and range.European Community's Seventh Framework ProgramPublicad

Trato digno y satisfacción del usuario externo de psiquiatría del Hospital Hermilio Valdizán, Santa Anita, 2018

El objetivo de esta investigación fue determinar la relación entre el trato digno y la satisfacción del usuario externo de psiquiatría del Hospital Hermilio Valdizán, Santa Anita, 2018. En cuanto a la metodología, esta investigación se desarrolló respetando todo el proceso del enfoque cuantitativo, manejo del diseño no experimental, el método fue el hipotético - deductivo, tipo de estudio descriptivo correlacional de corte transversal. La población del estudio fue constituida por los usuarios externos de psiquiatría del Hospital Hermilio Valdizán, Santa Anita, 2018 en un total de 657, de donde se tomó una muestra significativa de 234 pacientes a través del muestreo probabilístico al 95%. Para recolección de datos se utilizó la técnica denominada encuesta; y los instrumentos utilizados fueron cuestionarios con escalamiento Likert, validados oportunamente y con una fiabilidad muy alta a través de la prueba piloto con el Alfa de Cronbach. Los resultados han evidenciado que, el trato digno al usuario externo de psiquiatría del Hospital Hermilio Valdizán, Santa Anita, 2018, es para el 9,9% “deficiente”, el 45,3%, “regular” y el 44,9%, “eficiente”; y sobre la sat isfacción del usuario externo de psiquiatría, manifestaron: el 39,9% “regularmente satisfechos”, el 55,1%, “sat isfechos” y el 4,9%, “muy sat isfechos”. Las conclusiones fueron los hallazgos de una correlación positiva alta y significativa entre el trato digno y la satisfacción del usuario externo de psiquiatría del Hospital Hermilio Valdizán, Santa Anita, 2018, siendo el Rho de 0,870**; es decir, el índice de correlación fue al 87.0%. Confirmándose a mayor trato digno, mayor satisfacción del usuario externo

Monitoring system for carrier grade mesh networks

Proceedings of: 2010 Future Network & Mobile Summit, 16 - 18 June 2010, Florence, ItalyThe paper presents a monitoring system for carrier grade mesh networks. First, the system architecture, components and interfaces are described. Then the measured and discovered network parameters are discussed. A link prediction and trigger algorithm based on a modified meanreverting diffusion process is proposed. The results from analysis show that this function can significantly enhance link reliability.European Community's Seventh Framework ProgramPublicad

Topologies of wireless mesh networks with inband backhauling

Proceedings of: PIMRC 2010: 21st Annual IEEE International Symposium on Personal, Indoor and Mobile Radio Communications took place from 26-30 Sep. 2010 in Istanbul, TurkeyWireless mesh networks (WMNs) with in band backhauling use the same antennas for the backhaul as well as for the access. Therefore antennas of next hop neighbours need to be directed to each other. However, such a configuration is not possible in a three-sectorized hexagonal cell deployment. In this paper we derive several alternative topologies that are suitable for WMNs with in band backhauling. We show that a topology with four directional antennas per node and backhaul connectivity between indirect neighbours outperforms competing topologies in terms of handover rate, optimal maximum power, and system capacity.European Community's Seventh Framework ProgramPublicad

Supporting Carrier Grade Services over Wireless Mesh Networks: the approach of the European FP-7 STREP CARMEN

CARMEN is a three-year Specific Targeted Research Project (STREP) funded by the European Commission within the 7th Framework Program. The CARMEN access network will complement existing access technologies by exploiting low cost mesh networking techniques, thus minimizing deployment and maintenance costs. The CARMEN architecture introduces an abstraction layer that hides the specifics of the underlying access technology providing an abstract interface on top of which higher layers can be easily developed. This allows for the integration of current and future heterogeneous wireless technologies to provide scalable and efficient mobile ubiquitous Internet access, able to adapt to different environments and user requirements. Following these goals, CARMEN aims to define, study and implement link and technology abstractions, mobility support, and quality of service. The architecture also includes advanced monitoring features that allow for dynamic self-configuration, thereby reducing the installation and operational costs.European Community's Seventh Framework ProgramPublicad

Respiratory carriage of hypervirulent Klebsiella pneumoniae by indigenous populations of Malaysia

Klebsiella pneumoniae is a Gram-negative Enterobacteriaceae that is classified by the World Health Organisation (WHO) as a Priority One ESKAPE pathogen. South and Southeast Asian countries are regions where both healthcare associated infections (HAI) and community acquired infections (CAI) due to extended-spectrum β-lactamase (ESBL)-producing and carbapenem-resistant K. pneumoniae (CRKp) are of concern. As K. pneumoniae can also exist as a harmless commensal, the spread of resistance genotypes requires epidemiological vigilance. However there has been no significant study of carriage isolates from healthy individuals, particularly in Southeast Asia, and specially Malaysia. Here we describe the genomic analysis of respiratory isolates of K. pneumoniae obtained from Orang Ulu and Orang Asli communities in Malaysian Borneo and Peninsular Malaysia respectively. The majority of isolates were K. pneumoniae species complex (KpSC) 1 K. pneumoniae (n = 53, 89.8%). Four Klebsiella variicola subsp. variicola (KpSC3) and two Klebsiella quasipneumoniae subsp. similipneumoniae (KpSC4) were also found. It was discovered that 30.2% (n = 16) of the KpSC1 isolates were ST23, 11.3% (n = 6) were of ST65, 7.5% (n = 4) were ST13, and 13.2% (n = 7) were ST86. Only eight of the KpSC1 isolates encoded ESBL, but importantly not carbapenemase. Thirteen of the KpSC1 isolates carried yersiniabactin, colibactin and aerobactin, all of which harboured the rmpADC locus and are therefore characterised as hypervirulent. Co-carriage of multiple strains was minimal. In conclusion, most isolates were KpSC1, ST23, one of the most common sequence types and previously found in cases of K. pneumoniae infection. A proportion were hypervirulent (hvKp) however antibiotic resistance was low