Redes Multi-Celda Coordinadas con Información de Canal Limitada en el Transmisor

[ES] Las redes coordinadas están consideradas como una de las principales técnicas para mejorar la eficiencia espectral de los futuros sistemas de comunicaciones de banda ancha. En un sistema multi-celda coordinado, varias estaciones base transmiten a los usuarios y pueden intercambiar datos de usuario, información local de canal y otra información necesaria para la sincronización. Desde el punto de vista del usuario, la información del canal debe ser realimentada a las estaciones base para posibilitar el diseño de la precodificación. Uno de los mayores desafíos que presentan estas redes es el diseño de algoritmos eficientes que reduzca la complejidad del sistema. En este trabajo, se estudian las bases de estos sistemas y se proponen dos esquemas de coordinación basadas en un conocimiento limitado del canal por parte del transmisor: red con coordinación distribuida, donde sólo se dispone de información local del canal en cada estación base, y red con coordinación parcial, donde además no todas las estaciones base transmiten a los usuarios. Los resultados de las simulaciones muestran que estos esquemas mejoran significativamente las prestaciones de las redes convencionales en entornos limitados por la interferencia multi-usuario.[EN] Network coordination is considered as one of the fundamental techniques to improve the spectral efficiency of future broadband communication systems. In a coordinated multi-cell system, several base stations transmit to users and are able to exchange user data, local channel state information and other information for synchronization issues. From the user point of view, estimated channel state information needs to be fed back to its base stations to make precoding design possible. One of the major challenges associated with network coordination is the design of efficient algorithms which can result in lower complexity requirements. In this work, the background of these systems are studied and two network coordination schemes that rely on the use of limited channel state information at the transmitter side are proposed: distributed network coordination, where only local channel state information is available at each base station, and partial network coordination, where not all base stations are allowed to transmit to the users. Simulation results show that these schemes achieve significant gains when compared to conventional non-coordinated networks in multi-user interference-limited scenarios.Domene Oltra, F. (2009). Redes Multi-Celda Coordinadas con Información de Canal Limitada en el Transmisor. http://hdl.handle.net/10251/27144.Archivo delegad

El verbo auxiliar trivalente de los dialectos navarro y central

Artikulu honetan finkatu eta erakutsi dugu hiru kasuko ASM(NDE), /i/ duena, edin aditzari dagokiola. Hiru kasuko aditz laguntzaile gisa erabiltzen hasi zen hegoaldeko goi nafarreran, eta zehazki Iruñerrian. Hortik gaur egun hartzen duen lurralde osora zabaldu zen, komunikabide nagusien bidez, Bidasoa ibarrean barna Iruña eta Irun lotzen dituen bide ertzetan. -diantzinako erroa lehenaldiaren zenbait bariazio dialektaletan agertzen da oraindik. Orainaldian bokalen arteko /d/ galdu, eta gelditzen den [ai] diptongoa /i/ bilakatu zen. Halaber, hiru kasuko ASM(NDE) honen ergatiboaren 3. pertsonaren flexioetatik dator edin aditz laguntzaile beraren bi kasuko ASM(ND) intransitiboa. Honek ere [ai] diptongoa erakusten du erregulartasunez, eta izan aditzaren ASM(ND) iragangaitza -bi kasu dituenaordezkatu du. Geroago, z- aurrizki berriak ordezkatu zuen d- jatorrizko 3. pertsonaren aurrizkia, euskalki guztietan Uharte Arakilen izan ezik, bertan daurrizkiak iraun baitu. Hiru kasuko edin aditzaren ASM(NDE)an, [ai] diptongoa /i/ bilakatu zen, CF = ai > i bilakaerari jarraiki. Geroago, berdin gertatu zen Oiartzungo bi kasuko ASM(ND, edin) iragangaitzean. Hala ere, zenbait herritan antzinako [ai] diptongoak iraun du hiru kasuko ASM(NDE)an. In the present article, we have determined and demonstrated that the tricasual Verbal Morphological Structure (NDE) with /i/ belongs to the verb edin (to get), use of which as a trivalent auxiliary verb began in the Southern Navarrese dialect, and more specifically in the Pamplona area, from whence it spread to the rest of the territory in which it is now used via the main routes of communication, along the corridor which joins Pamplona with Irun through the Valley of Bidasoa. The old root -di- still appears in some dia - lectal variants of the past. The intervocalic /d/ was lost in the present and the resulting diphthong [ai] was reduced to /i/. In turn, the intransitive bicasual VMS(ND) of the auxiliary verb edin itself, which presents the diphthong [ai] in an equally regular manner, having substituted the intransitive bicasual VMS(ND) of izan, comes from the 3rd person ergative inflections of this tricasual VMS(NDE) of edin. Later, the original 3rd person prefix d- was replaced by the new prefix z- in all the dialects except in Uharte Arakil, where d- has been preserved. The diphthong [ai] was reduced to /i/ by the PC = ai > i in the tricasual VMS(NDE) of edin and, at a later stage, in Oiartzun’s new intransitive bicasual VMS(ND, edin), as well. The old diphthong [ai] has, however, been preserved in the tricasual VMS(NDE) in some localities

A limited feedback scheme based on spatially correlated channels for coordinated multipoint systems

High spectral efficiency can be achieved in the downlink of multi-antenna coordinated multi-point systems provided that the multiuser interference is appropriately managed at the transmitter side. For this sake, downlink channel information needs to be sent back by the users, thus reducing the rate available at the uplink channel. The amount and type of feedback information required has been extensively studied and many limited feedback schemes have been proposed lately. A common pattern to all of them is that achieving low rates of feedback information is possible at the cost of increasing complexity at the user side and, sometimes, assuming that some statistics of the channel are known. In this article, we propose a simple and versatile limited feedback scheme that exploits the spatial correlation at each multi-antenna base station (BS) without requiring any previous statistical information of the channel and without adding significant computational complexity. It is based on the separate quantization of the channel impulse response modulus and phase and it shows better mean square error performance than the standard scheme based on quantization of real and imaginary parts. In order to evaluate the performance of the downlink regarding multiuser interference management, different precoding techniques at the BSs, such as zero-forcing (ZF), Tomlinson-Harashima precoding (THP) and lattice reduction Tomlinson- Harashima precoding (LRTHP), have been evaluated. Simulations results show that LRTHP and THP present a higher robustness than ZF precoding against channel quantization errors but at the cost of a higher complexity at the BS. Regarding sum-capacity and bit error rate performances, our versatile scheme achieves better results than the standard one in the medium and high SNR regime, that is, in the region where quantization errors are dominant against noise, for the same feedback cost measured in bits per user

La función social e ideológica de las fiestas religiosas: identidad local, control social e instrumento de dominación

This article attempts to answer the question: what role have religious and patroness festivities in society, now and throughout history? They belong to what is called popular religiosity, are utilitarian —because they were used as a solution to natural and epidemic calamities— and are mainly a symbol of local or regional identity. But besides this, they have always had a social and ideological role, which can be summarized as maintaining the established social order, mainly by making that a part of the population identifies itself with the Crown and the ruling aristocracy. The parallel between God, the Virgin and the saints with the kings, feudal lords and members of the nobility in general favored that the same attitudes of obedience and submission that common people had toward the religious figures, they also had them to the social ruling figures (the nobility, the clergy and the subsequent absolute monarchy). Therefore, religious festivities (Easter, Christmas, Kings and, especially, the patron-saints’ festivities) were the most suitable cultural event to promote that the common people adopt these attitudes towards religious figures and, indirectly, also towards the civilian ones.El presente artículo intenta responder a la pregunta: ¿qué función tienen las fiestas religiosas y patronales en la sociedad, ahora y a lo largo de la Historia? Pertenecen a lo que se denomina religiosidad popular, son utilitaristas, porque se utilizaban como solución a las calamidades naturales y sanitarias, y son principalmente un símbolo de identidad local o regional. Pero, además, han tenido siempre una función social, que se podría resumir en el mantenimiento del orden social establecido mediante la identificación de parte de la población con la aristocracia dominante. El paralelismo entre Dios, la Virgen y los santos con los reyes, los señores feudales y los miembros de la nobleza en general favorecía que las mismas actitudes de obediencia y sumisión que el pueblo tenía hacia los personajes religiosos las tuviera también hacia los personajes de la sociedad feudal, la nobleza, el clero y la posterior monarquía absoluta. Las fiestas religiosas (Semana Santa, Navidad, Reyes Magos y, sobre todo, las fiestas patronales) eran, entonces, la manifestación cultural más idónea para propiciar que el pueblo llano adoptara estas actitudes hacia unos e, indirectamente, también hacia los otros

Channel Quantization Based on the Statistical Characterization of Spatially Correlated Fading

Multiuser multiple-input-multiple-output (MUMIMO) techniques, such as scheduling and precoding, have shown to improve the spectral efficiency of wireless communication systems. However, these techniques require an accurate knowledge of the channel of the different users at the transmitter. In frequency-division duplex (FDD) systems, this information has to be provided by the different users, motivating the research of efficient limited feedback schemes. This paper presents a novel statistical characterization of the spatial multiple-input-single-output (MISO) channel. In this characterization, one antenna is selected as the reference, and the channel fading experienced from this antenna is also considered to be the reference. The conditional probability density functions (CPDFs) of the envelope and phase of the channel fading coefficients from the rest of the antennas (denoted as nonreference channel fading and nonreference antennas) are obtained given the reference one. Based on this statistical characterization, this paper proposes a channel quantization scheme that individually quantizes the channel fading coefficient of each transmit antenna that is seen by each user. The envelope and phase of the reference channel fading are quantized considering a Rayleigh distribution and a uniform distribution, respectively. The nonreference channel fading coefficients are quantized according to their respective CPDFs, which in turn depend on the spatial correlation between each channel fading and the reference channel fading. Numerical simulations have been carried out to compare the performance of the proposed conditional quantization (CQ) scheme with a polar quantization (PQ) and with a quantization based on the Karhunen-Loève (KL) transform. PQ does not consider spatial correlation, CQ needs one spatial correlation coefficient per nonreference antenna, and the KL scheme makes use of the full spatial correlation matrix. The results show that CQ achieves a lower quantization mean square error (MSE) than the other two schemes in highly and moderately correlated environments. When the spatial channel model (SCM) is considered, the proposed scheme allows the spatial correlation to be successfully exploited in arrays with N=hbox4 and N=hbox8 transmit antennas for antenna separations that are lower than d=hbox1.3lambda and d=hbox0.75lambda, respectivelyThis work was supported by European Union ERDF and Spanish Government through Project TEC2012-38142-C04 and Generalitat Valenciana through Project PROME-TEOII/2014/003.Domene Oltra, F.; Piñero Sipán, MG.; Diego Antón, MD.; Gonzalez, A. (2015). Channel Quantization Based on the Statistical Characterization of Spatially Correlated Fading. IEEE Transactions on Vehicular Technology. 64(9):3931-3943. https://doi.org/10.1109/TVT.2014.2363170S3931394364

High performance lattice reduction on heterogeneous computing platform

The final publication is available at Springer via http://dx.doi.org/10.1007/s11227-014-1201-2The lattice reduction (LR) technique has become very important in many engineering fields. However, its high complexity makes difficult its use in real-time applications, especially in applications that deal with large matrices. As a solution, the modified block LLL (MB-LLL) algorithm was introduced, where several levels of parallelism were exploited: (a) fine-grained parallelism was achieved through the cost-reduced all-swap LLL (CR-AS-LLL) algorithm introduced together with the MB-LLL by Jzsa et al. (Proceedings of the tenth international symposium on wireless communication systems, 2013) and (b) coarse-grained parallelism was achieved by applying the block-reduction concept presented by Wetzel (Algorithmic number theory. Springer, New York, pp 323-337, 1998). In this paper, we present the cost-reduced MB-LLL (CR-MB-LLL) algorithm, which allows to significantly reduce the computational complexity of the MB-LLL by allowing the relaxation of the first LLL condition while executing the LR of submatrices, resulting in the delay of the Gram-Schmidt coefficients update and by using less costly procedures during the boundary checks. The effects of complexity reduction and implementation details are analyzed and discussed for several architectures. A mapping of the CR-MB-LLL on a heterogeneous platform is proposed and it is compared with implementations running on a dynamic parallelism enabled GPU and a multi-core CPU. The mapping on the architecture proposed allows a dynamic scheduling of kernels where the overhead introduced is hidden by the use of several CUDA streams. Results show that the execution time of the CR-MB-LLL algorithm on the heterogeneous platform outperforms the multi-core CPU and it is more efficient than the CR-AS-LLL algorithm in case of large matrices.Financial support for this study was provided by grants TAMOP-4.2.1./B-11/2/KMR-2011-0002, TAMOP-4.2.2/B-10/1-2010-0014 from the Pazmany Peter Catholic University, European Union ERDF, Spanish Government through TEC2012-38142-C04-01 project and Generalitat Valenciana through PROMETEO/2009/013 project.Jozsa, CM.; Domene Oltra, F.; Vidal Maciá, AM.; Piñero Sipán, MG.; González Salvador, A. (2014). High performance lattice reduction on heterogeneous computing platform. Journal of Supercomputing. 70(2):772-785. https://doi.org/10.1007/s11227-014-1201-2S772785702Józsa CM, Domene F, Piñero G, González A, Vidal AM (2013) Efficient GPU implementation of lattice-reduction-aided multiuser precoding. In: Proceedings of the tenth international symposium on wireless communication systems (ISWCS 2013)Wetzel S (1998) An efficient parallel block-reduction algorithm. In: Buhler JP (ed) Algorithmic number theory. Lecture notes in computer science, vol 1423. Springer, Berlin, Heidelberg, pp 323–337Wubben D, Seethaler D, Jaldén J, Matz G (2011) Lattice reduction. Signal Process Mag IEEE 28(3):70–91Lenstra AK, Lenstra HW, Lovász L (1982) Factoring polynomials with rational coefficients. Math Ann 261(4):515–534Bremner MR (2012) Lattice basis reduction: an introduction to the LLL algorithm and its applications. CRC Press, USAWu D, Eilert J, Liu D (2008) A programmable lattice-reduction aided detector for MIMO-OFDMA. In: 4th IEEE international conference on circuits and systems for communications (ICCSC 2008), pp 293–297Barbero LG, Milliner DL, Ratnarajah T, Barry JR, Cowan C (2009) Rapid prototyping of Clarkson’s lattice reduction for MIMO detection. In: IEEE international conference on communications (ICC’09), pp 1–5Gestner B, Zhang W, Ma X, Anderson D (2011) Lattice reduction for MIMO detection: from theoretical analysis to hardware realization. IEEE Trans Circ Syst I Regul Pap 58(4):813–826Shabany M, Youssef A, Gulak G (2013) High-throughput 0.13- \upmu μ m CMOS lattice reduction core supporting 880 Mb/s detection. IEEE Trans Very Large Scale Integr (VLSI) Syst 21(5):848–861Luo Y, Qiao S (2011) A parallel LLL algorithm. In: Proceedings of the fourth international C* conference on computer science and software engineering, pp 93–101Backes W, Wetzel S (2011) Parallel lattice basis reduction—the road to many-core. In: IEEE 13th international conference on high performance computing and communications (HPCC)Ahmad U, Amin A, Li M, Pollin S, Van der Perre L, Catthoor F (2011) Scalable block-based parallel lattice reduction algorithm for an SDR baseband processor. In: 2011 IEEE international conference on communications (ICC)Villard G (1992) Parallel lattice basis reduction. In: Papers from the international symposium on symbolic and algebraic computation (ISSAC’92). ACM, New YorkDomene F, Józsa CM, Vidal AM, Piñero G, Gonzalez A (2013) Performance analysis of a parallel lattice reduction algorithm on many-core architectures. In: Proceedings of the 13th international conference on computational and mathematical methods in science and engineeringGestner B, Zhang W, Ma X, Anderson DV (2008) VLSI implementation of a lattice reduction algorithm for low-complexity equalization. In: 4th IEEE international conference on circuits and systems for communications (ICCSC 2008), pp 643–647Burg A, Seethaler D, Matz G (2007) VLSI implementation of a lattice-reduction algorithm for multi-antenna broadcast precoding. In: IEEE international symposium on circuits and systems (ISCAS 2007), pp 673–676Bruderer L, Studer C, Wenk M, Seethaler D, Burg A (2010) VLSI implementation of a low-complexity LLL lattice reduction algorithm for MIMO detection. In: Proceedings of 2010 IEEE international symposium on circuits and systems (ISCAS

Homoparenting as a public health issue: a scoping review

OBJETIVO: Mapear a produção científica global sobre homoparentalidade no campo da saúde coletiva ou saúde pública. MÉTODOS: Em termos de procedimentos metodológicos, foi realizada uma revisão de escopo, tendo como norte a seguinte pergunta: quais são os aspectos abordados na produção científica global a respeito de famílias homoparentais no campo da saúde coletiva ou pública? As buscas foram realizadas em sete fontes de literatura científica, sendo incluídos 58 estudos, envolvendo artigos científicos e dissertações. O tratamento analítico dado aos estudos, em sua maioria qualitativos, seguiu a técnica de análise de conteúdo na modalidade temática. RESULTADOS: Os resultados indicam que percepções de homossexuais e de profissionais sobre cuidados prestados e serviços de saúde em geral foi a temática abordada por maior número de estudos (n = 31), seguida de contexto heteronormativo dos serviços de saúde (n = 26); revelação da orientação sexual (n = 20); fertilização (n = 14); informações e ações educativas (n = 5). CONCLUSÃO: Embora a questão da homoparentalidade venha sendo discutida em alguns setores da saúde, há ciência de que é preciso contar com uma base consolidada por meio de inúmeros estudos ao se problematizar essa temática. Conclui-se que, dentre outros aspectos, que o escopo desta revisão não é problematizado de forma suficiente no âmbito da formação e atuação de profissionais de saúde.OBJECTIVE: To map global scientific production on homoparenting in the field of collective health or public health. METHODS: In terms of methodological procedures, a scoping review was carried out, guided by the following question: What are the aspects addressed in global scientific production regarding homoparental families in the field of collective or public health? The searches were carried out in seven sources of scientific literature, including 58 studies, involving scientific articles and dissertations. The analytical treatment given to the studies, most of which were qualitative, followed the content analysis technique in the thematic modality. RESULTS: The results indicate that the perceptions of homosexuals and professionals about the care provided and health services in general was the topic addressed by the largest number of studies (n = 31), followed by heteronormative context of health services (n = 26); disclosure of sexual orientation (n = 20); fertilization (n = 14); educational information and actions (n = 5). CONCLUSION: Although the issue of same-sex parenthood has been discussed in some health sectors, there is awareness that it is necessary to rely on a consolidated basis through numerous studies when discussing this issue. It is concluded that, among other aspects, the scope of this review is not sufficiently problematized within the scope of health professionals’ training and performance

Dietary reference intakes: application of tables in nutritional studies

Diet planning and food intake evaluation are professional activities classically performed by comparing mean values of ingestion against reference values of nutrient and energy intakes, for either groups or individuals. Without considering certain intrinsic limitations of the reference values, such task may render equivocal conclusions with regard to nutritional adequacy. The nutritional recommendations, prepared as a joint effort between the US Institute of Medicine and Health Canada published since 1997 and known as Dietary Reference Intakes, offer a new model by establishing indices of nutrient intake and refining the concept of risk associated with diet evaluation. Errors of both intra and interindividual nature, due to the variability of an individual's feeding pattern, the uneven distribution of requirements within a population, respectively, and the small number of days of observation, are factors that together can have a large impact on the confidence of the analysis. For these reasons, only the judicious selection of the reference values, published in the form of tables from 1997 through 2005, should enable the user to reach the proper assessment. This paper had the objective of highlighting various critical characteristics of application and compiling the values in order to facilitate their use by both professionals and students of the area.As avaliações de dietas e o planejamento de consumo são atividades tradicionalmente realizadas por meio da comparação de médias de ingestão contra valores de referência de energia e nutrientes, seja para indivíduos ou grupos. Limitações de ordem técnica devem ser levadas em conta, sem as quais se pode chegar a conclusões equivocadas quanto ao atendimento das necessidades nutricionais. As Recomendações Nutricionais propostas pelo Institute of Medicine dos Estados Unidos, em conjunto com a agência Health Canada, a partir de 1997, conhecidas como Dietary Reference Intakes, representam um novo paradigma para o estabelecimento de indicadores nutricionais de consumo, ao aperfeiçoarem o uso do conceito de risco na avaliação de dietas. Fontes de erro intra ou interindividuais, devidas à variabilidade de padrão de consumo e decorrentes da distribuição das necessidades na população, aliadas a um pequeno número de dias de observação, têm grande impacto sobre a confiabilidade da análise. Por esta razão devem orientar a utilização dos valores, que foram organizados em tabelas com as quatro categorias de nutrientes, publicadas entre 1997 e 2005. O presente trabalho teve por objetivo destacar algumas características de aplicação e consolidar os valores diários de Tolerable Upper Intake Level, Adequate Intake e Recommended Dietary Allowance, facilitando a consulta por parte de profissionais e estudantes da área de nutrição.74176

Posição da Sociedade Brasileira de Hérnia e Parede Abdominal sobre o tratamento de grandes hérnias de hiato.

Large hiatal hernias (LHH) besides being more prevalent in the elderly, have different clinical presentation: fewer reflux, more mechanical symptoms and a greater possibility of acute, life-threatening complications such as gastric volvulus, ischemia and visceral mediastinal perforation. Thus, surgical indications are distinct from gastroesophageal reflux disease (GERD-related), sliding hiatal hernias. Heartburn tends to be less intense, while symptoms of chest pain, cough, discomfort, and tiredness are reported more frequently. Complaints of vomiting and dysphagia may suggest the presence of associated gastric volvulus. Signs of iron deficiency and anemia are found. Surgical indication is still controversial and was previously based on high mortality reported in emergency surgeries for gastric volvulus. Postoperative mortality is especially related to three factors: body mass index (BMI above 35), age over 70 years and presence of comorbidity. Minimally invasive elective surgery should be offered to symptomatic individuals with good or reasonable performance status, regardless of age group. In asymptomatic and oligosymptomatic patients, besides obviously identifying the patient's desire, case-by-case analysis of surgical risk factors such as age, obesity and comorbidities, should be taken under consideration. One should also pay attention to situations with greater technical difficulty and risks of acute migration due to increased abdominal pressure (abdominoplasty, manual workers, spastic diseases). Technical alternatives such as partial fundoplication and anterior gastropexy can be considered. We emphasize the importance of performing surgical procedures in cases of LHH in high-volume centers, with experienced surgeons.As grandes hérnias de hiato (HHG), além de serem mais prevalentes em idosos, têm apresentação clínica diferente: menos refluxo, mais sintomas mecânicos e maior possibilidade de complicações agudas e potencialmente fatais, como vólvulo gástrico, isquemia e perfuração mediastinal visceral. Assim, as indicações cirúrgicas são distintas das hérnias de hiato por deslizamento, relacionadas à doença do refluxo gastroesofágico (DRGE). A azia tende a ser menos intensa, enquanto os sintomas de dor no peito, tosse, desconforto e cansaço são relatados com maior frequência. Queixas de vômitos e disfagia podem sugerir a presença de volvo gástrico associado. São encontrados sinais de deficiência de ferro e anemia. A indicação cirúrgica ainda é controversa e foi anteriormente baseada na alta mortalidade relatada em cirurgias de emergência para volvo gástrico. A mortalidade pós-operatória está especialmente relacionada a três fatores: índice de massa corporal (IMC acima de 35), idade superior a 70 anos e presença de comorbidades. A cirurgia eletiva minimamente invasiva deve ser oferecida a indivíduos sintomáticos, com desempenho bom ou razoável, independentemente da faixa etária. Em pacientes assintomáticos e oligossintomáticos, além de obviamente identificar o desejo do paciente, deve-se levar em consideração a análise caso a caso dos fatores de risco cirúrgico, como idade, obesidade e comorbidades. Deve-se atentar também para situações de maior dificuldade técnica e riscos de migração aguda por aumento da pressão abdominal (abdominoplastia, trabalhos manuais, doenças espásticas). Alternativas técnicas como fundoplicatura parcial e gastropexia anterior podem ser consideradas. Ressaltamos a importância da realização de procedimentos cirúrgicos nos casos de GHH em centros de grande volume, com cirurgiões experientes