Noncooperative and Cooperative Transmission Schemes with Precoding and Beamforming

The next generation mobile networks are expected to provide multimedia applications with a high quality of service. On the other hand, interference among multiple base stations (BS) that co-exist in the same location limits the capacity of wireless networks. In conventional wireless networks, the base stations do not cooperate with each other. The BSs transmit individually to their respective mobile stations (MS) and treat the transmission from other BSs as interference. An alternative to this structure is a network cooperation structure. Here, BSs cooperate with other BSs to simultaneously transmit to their respective MSs using the same frequency band at a given time slot. By doing this, we significantly increase the capacity of the networks. This thesis presents novel research results on a noncooperative transmission scheme and a cooperative transmission scheme for multi-user multiple-input-multiple-output orthogonal frequency division multiplexing (MIMO-OFDM). We first consider the performance limit of a noncooperative transmission scheme. Here, we propose a method to reduce the interference and increase the throughput of orthogonal frequency division multiplexing (OFDM) systems in co-working wireless local area networks (WLANs) by using joint adaptive multiple antennas(AMA) and adaptive modulation (AM) with acknowledgement (ACK) Eigen-steering. The calculation of AMA and AM are performed at the receiver. The AMA is used to suppress interference and to maximize the signal-to-interference-plus-noise ratio (SINR). The AM scheme is used to allocate OFDM sub-carriers, power, and modulation mode subject to the constraints of power, discrete modulation, and the bit error rate (BER). The transmit weights, the allocation of power, and the allocation of sub-carriers are obtained at the transmitter using ACK Eigen-steering. The derivations of AMA, AM, and ACK Eigen-steering are shown. The performance of joint AMA and AM for various AMA configurations is evaluated through the simulations of BER and spectral efficiency (SE) against SIR. To improve the performance of the system further, we propose a practical cooperative transmission scheme to mitigate against the interference in co-working WLANs. Here, we consider a network coordination among BSs. We employ Tomlinson Harashima precoding (THP), joint transmit-receive beamforming based on SINR (signal-to-interference-plus-noise-ratio) maximization, and an adaptive precoding order to eliminate co-working interference and achieve bit error rate (BER) fairness among different users. We also consider the design of the system when partial channel state information (CSI) (where each user only knows its own CSI) and full CSI (where each user knows CSI of all users) are available at the receiver respectively. We prove analytically and by simulation that the performance of our proposed scheme will not be degraded under partial CSI. The simulation results show that the proposed scheme considerably outperforms both the existing noncooperative and cooperative transmission schemes. A method to design a spectrally efficient cooperative downlink transmission scheme employing precoding and beamforming is also proposed. The algorithm eliminates the interference and achieves symbol error rate (SER) fairness among different users. To eliminate the interference, Tomlinson Harashima precoding (THP) is used to cancel part of the interference while the transmit-receive antenna weights cancel the remaining one. A new novel iterative method is applied to generate the transmit-receive antenna weights. To achieve SER fairness among different users and further improve the performance of MIMO systems, we develop algorithms that provide equal SINR across all users and order the users so that the minimum SINR for each user is maximized. The simulation results show that the proposed scheme considerably outperforms existing cooperative transmission schemes in terms of the SER performance and complexity and approaches an interference free performance under the same configuration. We could improve the performance of the proposed interference cancellation further. This is because the proposed interference cancellation does not consider receiver noise when calculating the transmit-receive weight antennas. In addition, the proposed scheme mentioned above is designed specifically for a single-stream multi-user transmission. Here, we employ THP precoding and an iterative method based on the uplink-downlink duality principle to generate the transmit-receive antenna weights. The algorithm provides an equal SINR across all users. A simpler method is then proposed by trading off the complexity with a slight performance degradation. The proposed methods are extended to also work when the receiver does not have complete Channel State Informations (CSIs). A new method of setting the user precoding order, which has a much lower complexity than the VBLAST type ordering scheme but with almost the same performance, is also proposed. The simulation results show that the proposed schemes considerably outperform existing cooperative transmission schemes in terms of SER performance and approach an interference free performance. In all the cooperative transmission schemes proposed above, we use THP to cancel part of the interference. In this thesis, we also consider an alternative approach that bypasses the use of THP. The task of cancelling the interference from other users now lies solely within the transmit-receive antenna weights. We consider multiuser Gaussian broadcast channels with multiple antennas at both transmitter and receivers. An iterative multiple beamforming (IMB) algorithm is proposed, which is flexible in the antenna configuration and performs well in low to moderate data rates. Its capacity and bit error rate performance are compared with the ones achieved by the traditional zero-forcing method

L'utilizzo di OpenStreetMap all'interno del Club Alpino Italiano

La collaborazione tra il Club Alpino Italiano (CAI) e OpenStreetMap (OSM) è iniziata ufficialmente con la firma di una convenziona tra lo stesso CAI e Wikimedia Italia, il capitolo italiano della OSM Foundation, nel 2016. A tre anni da quella firma molto è stato fatto con un'impennata nell'ultimo anno anche grazie al finanziamento del CAI attraverso il "CONTRATTO PER IL SERVIZIO DI IMPLEMENTAZIONE DATI NEL SISTEMA INFOMONT". Nella presentazione verranno illustrate le attività svolte: - l'inserimento dati in OSM con la procedura utilizzata e la situazione regione per regione - lo sviluppo di un software rilasciato con una licenza FOSS in grado di ottenere i dati relativi al CAI da OSM e svolgere alcune operazioni di conversione e reportistica - le attività di formazion

Tobacco Cessation Services in Addiction Treatment: What Do Clients Say?

ObjectiveSpecialty addiction programs treat people who are addicted to alcohol, opioids, stimulants, and other drugs. This study identified the proportion of addiction program clients who received tobacco-related services and factors associated with receipt of such services.MethodsIn 2015 and 2016, clients (N=2,119) in 24 programs were surveyed for receipt of services aligning with three of the five As of tobacco cessation: ask, advise, assist. Multivariate analyses examined factors associated with receipt of each service.ResultsMost clients (76%) were asked about smoking. Among smokers (N=1,630), 53% were advised to quit, 41% received counseling, 26% received cessation medication, and 17% received counseling and medication. Clients were more likely to receive tobacco-related services if they wanted help quitting smoking or were enrolled in programs with tobacco-free grounds.ConclusionsThese correlational findings suggest that increasing client motivation to quit and implementing tobacco-free policies on the grounds of treatment centers may increase tobacco-related services in addiction treatment

Comparison of machine learning clustering algorithms for detecting heterogeneity of treatment effect in acute respiratory distress syndrome: A secondary analysis of three randomised controlled trials

BACKGROUND: Heterogeneity in Acute Respiratory Distress Syndrome (ARDS), as a consequence of its non-specific definition, has led to a multitude of negative randomised controlled trials (RCTs). Investigators have sought to identify heterogeneity of treatment effect (HTE) in RCTs using clustering algorithms. We evaluated the proficiency of several commonly-used machine-learning algorithms to identify clusters where HTE may be detected. METHODS: Five unsupervised: Latent class analysis (LCA), K-means, partition around medoids, hierarchical, and spectral clustering; and four supervised algorithms: model-based recursive partitioning, Causal Forest (CF), and X-learner with Random Forest (XL-RF) and Bayesian Additive Regression Trees were individually applied to three prior ARDS RCTs. Clinical data and research protein biomarkers were used as partitioning variables, with the latter excluded for secondary analyses. For a clustering schema, HTE was evaluated based on the interaction term of treatment group and cluster with day-90 mortality as the dependent variable. FINDINGS: No single algorithm identified clusters with significant HTE in all three trials. LCA, XL-RF, and CF identified HTE most frequently (2/3 RCTs). Important partitioning variables in the unsupervised approaches were consistent across algorithms and RCTs. In supervised models, important partitioning variables varied between algorithms and across RCTs. In algorithms where clusters demonstrated HTE in the same trial, patients frequently interchanged clusters from treatment-benefit to treatment-harm clusters across algorithms. LCA aside, results from all other algorithms were subject to significant alteration in cluster composition and HTE with random seed change. Removing research biomarkers as partitioning variables greatly reduced the chances of detecting HTE across all algorithms. INTERPRETATION: Machine-learning algorithms were inconsistent in their abilities to identify clusters with significant HTE. Protein biomarkers were essential in identifying clusters with HTE. Investigations using machine-learning approaches to identify clusters to seek HTE require cautious interpretation. FUNDING: NIGMS R35 GM142992 (PS), NHLBI R35 HL140026 (CSC); NIGMS R01 GM123193, Department of Defense W81XWH-21-1-0009, NIA R21 AG068720, NIDA R01 DA051464 (MMC)

Intoxicación por Brugmansia arborea (Solanaceae) en un canino

Los animales de compañía pueden ser víctimas de intoxicaciones de diferente origen, constituyendo las plantas un 10-15% de las etiologías reportadas. Brugmansia arborea sin. Datura arborea (floripondio, trompeta de ángel) es un arbusto o árbol pequeño, perenne, con flores blancas, cónicas y pendulares, que se encuentra distribuido mundialmente, utilizándose como planta ornamental en jardines. El género Brugmansia posee un alto contenido de alcaloides del tropano como escopolamina, hiosciamina y atropina, que antagonizan las acciones de la acetilcolina y los receptores colinérgicos muscarínicos. En la bibliografía se encuentran documentados numerosos casos de intoxicación por esta planta en seres humanos, provocando un síndrome anticolinérgico, parálisis flácida, convulsiones y muerte. En el presente trabajo se describe por primera vez el diagnóstico de un caso de intoxicación por Brugmansia arborea en un perro de dos meses de edad. Se describen los signos clínicos observados y su correlación con los reportados en casos humanos

Pterocarya stenoptera (Juglandaceae), una nueva especie exótica en los bosques de Celtis tala en un área natural protegida de la provincia de Buenos Aires (Argentina)

Los bosques de Celtis tala, o talares, de la provincia de Buenos Aires (Argentina), constituyen un frágil ecosistema amenazado por invasiones biológicas. Entre las especies exóticas reportadas como invasoras o transformadoras del paisaje en los talares, Ligustrum lucidum constituye la principal amenaza. En este trabajo se evalúa el grado de naturalización de Pterocarya stenoptera C. DC. (Juglandaceae), nueva en los talares de la Reserva Privada El Destino, ubicada dentro de la Reserva de Biósfera Parque Costero del Sur. Se estudió el uso local de la especie, el posible origen y tipo de dispersión, y se estableció su extensión y cantidad de renovales por metro cuadrado en los sectores invadidos. Se describe a la especie y se provee una clave dicotómica para diferenciar los géneros de Juglandaceae presentes en la provincia de Buenos Aires, todos ellos exóticos. Pterocarya stenoptera posiblemente haya sido cultivada en los jardines de la Estancia El Destino, desde donde se dispersó hacia los talares vecinos por anemocoria. Se encontraron tres sectores bien delimitados con gran cantidad de renovales. Esta especie, de reciente naturalización, posee medios de dispersión eficientes y una gran biomasa de semillas que le han permitido volverse un árbol dominante en algunos sitios, superando en cantidad de renovales a la invasora (transformadora) Ligustrum lucidum. Se prevé que el avance de Pterocarya stenoptera sobre el talar irá en aumento a menos que se planifique algún tipo de contención sobre la especie. En este marco, sostenemos que es necesario y posible planificar acciones para su manejo y control

Sentient Spaces: Intelligent Totem Use Case in the ECSEL FRACTAL Project

The objective of the FRACTAL project is to create a novel approach to reliable edge computing. The FRACTAL computing node will be the building block of scalable Internet of Things (from Low Computing to High Computing Edge Nodes). The node will also have the capability of learning how to improve its performance against the uncertainty of the environment. In such a context, this paper presents in detail one of the key use cases: an Internet-of-Things solution, represented by intelligent totems for advertisement and wayfinding services, within advanced ICT-based shopping malls conceived as a sentient space. The paper outlines the reference scenario and provides an overview of the architecture and the functionality of the demonstrator, as well as a roadmap for its development and evaluation

Growth, blood metabolites and hormones in calves fed diets with different amounts of energy and protein during the pre- or post-weaning periods

We investigated the effects of diets differing in energy and protein concentrations given during pre- and post-weaning on hormone and metabolite levels in association to parameters of growth. Sixteen Aberdeen Angus calves four-day-old were allocated in individual pens during 105 days in a randomized complete design. Animals consumed ad libitum various diets differing in proportion of energy and protein (A: 80% of concentrate, 20% alfalfa hay; B: 60% concentrate, 40% of alfalfa hay; C: 40% concentrate, 60% alfalfa hay, and D: 20% concentrate, 80% alfalfa hay). Also, calves consumed milk substitute up to 60-day-old day. Serum growth hormone and cortisol levels were not altered with diet changes (P > 0.05) neither during the pre- nor the post-weaning periods. Plasma insulin concentration average daily intake, glucose and thyroid hormone levels, and concentrations of ammonia nitrogen and propionic acid were greater (P < 0.01) for diets having higher than lower energy and protein levels during the post-weaning but not during the pre-weaning period. These results suggest inclusion of higher amounts of concentrate in the diet of weaned calves.Fil: Fernández, H. T.. Universidad Nacional del Sur. Departamento de Agronomía; ArgentinaFil: Busso, Carlos Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Centro de Recursos Naturales Renovables de la Zona Semiarida. Universidad Nacional del Sur. Centro de Recursos Naturales Renovables de la Zona Semiarida; ArgentinaFil: Laborde, Hugo Eduardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Centro de Recursos Naturales Renovables de la Zona Semiarida. Universidad Nacional del Sur. Centro de Recursos Naturales Renovables de la Zona Semiarida; ArgentinaFil: Torrea, M. B.. Universidad Nacional del Sur. Departamento de Agronomía; ArgentinaFil: Fernández, L. M.. Universidad Nacional del Sur. Departamento de Biología, Bioquímica y Farmacia; ArgentinaFil: López, G. H.. Universidad Nacional del Sur. Departamento de Biología, Bioquímica y Farmacia; ArgentinaFil: Delucchi, F.. Universidad Nacional del Sur. Departamento de Biología, Bioquímica y Farmacia; ArgentinaFil: García, B. N.. Universidad Nacional del Sur. Departamento de Biología, Bioquímica y Farmacia; Argentin

Expectancies regarding the interaction between smoking and substance use in alcohol-dependent smokers in early recovery.

The purpose of this study was to investigate expectancies regarding the interaction between cigarette smoking and use of alcohol among alcohol-dependent smokers in early recovery, using the Nicotine and Other Substances Interaction Expectancies Questionnaire (NOSIE). Participants were 162 veterans, 97% male, with a mean age of 50 years, enrolled in a clinical trial aimed at determining the efficacy of an intensive smoking cessation intervention versus usual care. At baseline, participants were assessed on measures of smoking behavior, abstinence thoughts about alcohol and tobacco use, symptoms of depression, and smoking-substance use interaction expectancies. In addition, biologically verified abstinence from tobacco and alcohol was assessed at 26 weeks. Participants reported that they expected smoking to have less of an impact on substance use than substance use has on smoking (p &lt; .001). Severity of depressive symptoms was significantly associated with the expectancy that smoking provides a way of coping with the urge to use other substances (p &lt; .01). The expectation that smoking increases substance urges/use was predictive of prospectively measured and biologically verified abstinence from smoking at 26 weeks (p &lt; .03). The results add to our knowledge of smoking-substance use interaction expectancies among alcohol-dependent smokers in early recovery and will inform the development of more effective counseling interventions for concurrent alcohol and tobacco use disorders