Studies of nucleotide sequences in TMV-RNA. II - The action of spleen diesterase

Spleen diesterase action on polynucleotide and ribonucleic acid infectivit

Directional propagation channel estimation and analysis in urban environment with panoramic photography

International audienceThis article aims to provide readers with a physical understanding of the propagation channel that is complementary to mathematical channel modeling. It presents an analysis of the directional propagation channel based on radiophotos. Radiophotos are graphical objects where directions of arrival are superimposed on three-dimensional (3D) panoramic photographs.The interaction between electro magnetic waves and the environment is immediately identified with these representations. This paper focuses on the direction of arrival at mobile in an urban macrocell environment. The first radiophoto collection illustrates the major propagation phenomena such as reflection, diffraction, or street canyoning. The second collection illustrates typical propagation channel profiles that are classified according to delay, azimuth, and elevation spread values. The paper also describes an original panorama-based method for estimating noise level in the azimuth–elevation domain

Typical MIMO propagation channels in urban macrocells at 2GHz

International audienceA directional wideband measurement campaign was performed in urban macrocells at 2 GHz using a channel sounder and a 8-sensor linear antenna array at the base station. Directions of arrival at the Base Station (BS) were estimated by beamforming using the antenna array. Directions of arrival at the Mobile Station (MS) were estimated by beamforming using parts of the measurement route. Global parameters (delay spread, azimuth spread at BS, maximum factor and street canyon factor) were processed from the Azimuth-Delay Power Profiles (ADPP) at BS and MS. In this paper, we compare the statistics of these four parameters with the statistics of those simulated by the 3GPP-SCM system-level model and the statistics of those reported in the literature. We find an acceptable agreement between our measurements and the SCM model except for the delay spread and the street canyon factor. The azimuth spread at BS mean Value (9.5°) and delay spread mean value (0.250 μs) are also in accordance with values reported in other references. Azimuth spreads are ranged from 7° to 11°, and delay spreads are ranged from 0.1 μs to 1 μs. From a statistical analysis of global parameters, we show that most of the measured propagation Channels can be classified in three main categories: low spatial diversity at MS and BS, high spatial diversity at MS and BS, low spatial diversity at BS and high spatial diversity at MS

On the Frequency Dependency of Radio Channel's Delay Spread: Analyses and Findings From mmMAGIC Multi-frequency Channel Sounding

This paper analyzes the frequency dependency of the radio propagation channel's root mean square (rms) delay spread (DS), based on the multi-frequency measurement campaigns in the mmMAGIC project. The campaigns cover indoor, outdoor, and outdoor-to-indoor (O2I) scenarios and a wide frequency range from 2 to 86 GHz. Several requirements have been identified that define the parameters which need to be aligned in order to make a reasonable comparison among the different channel sounders employed for this study. A new modelling approach enabling the evaluation of the statistical significance of the model parameters from different measurements and the establishment of a unified model is proposed. After careful analysis, the conclusion is that any frequency trend of the DS is small considering its confidence intervals. There is statistically significant difference from the 3GPP New Radio (NR) model TR 38.901, except for the O2I scenario.Comment: This paper has been accepted to the 2018 12th European Conference on Antennas and Propagation (EuCAP), London, UK, April 201

Filtro de Kalman na gestão de risco com foco em custo e prazo: um estudo de caso

TCC (graduação) - Universidade Federal de Santa Catarina. Centro Tecnológico. Engenharia Civil.Os processos de orçamentação e definição do cronograma buscam garantir o cumprimento dos custos e prazos, definidos no início de um projeto de construção civil. Entretanto, o caráter dinâmico desta indústria suscita incertezas que devem ser observadas e analisadas de maneira atenta. Nesse sentido, o gerenciamento de riscos compreende técnicas e ferramentas que tem como finalidade eliminar ou dirimir os efeitos decorrentes destes riscos. Dentre esses processos, ressalta-se a análise quantitativa dos riscos, a qual pode ser feita por meio de simulações ou modelos de previsão. Neste contexto, o modelo de previsão com a utilização do Filtro de Kalman apresenta-se como uma alternativa de ferramenta, com um procedimento simples, claro e bem definido. Com poucos dados de entrada e em qualquer momento da implantação, o modelo é capaz de estimar o custo e a duração no término do projeto. Este trabalho apresenta um estudo de caso com a utilização do modelo de previsão com Filtro de Kalman na gestão de risco, com foco no custo e duração do empreendimento. Foi utilizado um projeto não usual, em fase de concepção arquitetônica, a partir do qual elaborou-se seu orçamento e cronograma. Na sequência, realizou-se a identificação e análise dos riscos inerentes ao projeto, propondo-se ações de resposta ao risco, subsidiadas pelos resultados das simulações. Os resultados obtidos exemplificam que as simulações realizadas com o Filtro de Kalman incorporam ponderações que vão além do simples reordenamento dos desembolsos e cronograma. Assim, o modelo de previsão com o Filtro de Kalman subsidia a tomada de decisão relacionada a respostas aos riscos, garante maior precisão e transparência na determinação de aditivos para obras públicas e também maior exatidão na deliberação de reservas de contingência.Budgeting and planning processes seek to ensure compliance with the cost and schedule, set at the beginning of a construction project. However, the dynamic nature of this industry raises uncertainties that must be observed and analyzed in an attentive way. Therefore, risk management includes tools and techniques that aim to eliminate or minimize the effects of these risks. Among these processes, the quantitative risk analysis, which can be done through simulations or predictive models, is emphasized. In this context, the predictive model using the Kalman filter is presented as an alternative tool, with a simple, clear and well-defined procedure. With few input data and at any time of the implementation, the model is able to estimate the cost and duration of the project at completion. This paper presents a case study using the predictive model with Kalman filter in risk management, focusing on the cost and time of the project. An unusual project, still in architectural concept stage, was used, from which the project’s budget and planning were established. Furthermore, the identification and analysis of risks inherent to the project were conducted, and responsive actions to risk, subsidized by the results of the simulations, were proposed. The results illustrate that the simulations conducted with the Kalman filter incorporate considerations beyond the simple rearrangement of disbursements and schedule. Thus, the predictive model with Kalman filter supports the decision making related to risk response, ensures greater accuracy and transparency in the determination of additives for public contracts and also higher preciseness in the resolution of contingency reserves

Characterization, modeling and simulation of the MIMO propagation channel

International audienceThis article deals with several aspects relative to the MIMO propagation channel. Based on simulations and/or measurements, different approaches are used to model the propagation channel. These models are useful for the MIMO system design. Several studies are performed in order to realize realistic simulation of MIMO channel. Different measurement techniques are used in characterizing the propagation channel in various environments. Measurement campaigns made in different situations have been analyzed to obtain the relevant statistical parameters of the channel. Simulation of MIMO channel is then presented. Measurement and simulation results provide an evaluation of the capacity of MIMO channel. Obtained results show feasibility in the integration of MIMO techniques in practical wireless communication systems.Cet article traite de plusieurs aspects relatifs au canal de propagation MIMO. Différentes approches, basées sur des simulations et des mesures, utilisées pour modéliser le canal sont d’abord présentées. Ensuite, les différentes techniques de mesure utilisées dans le but de caractériser le canal de propagation dans divers milieux sont décrites. Des campagnes de mesures effectuées dans différents environnements sont analysées pour obtenir les paramètres statistiques du canal. Quelques problématiques liées à la simulation du canal MIMO sont évoquées notamment en lien avec une simulation réaliste dans des milieux complexes. Les résultats obtenus, en simulation comme en mesure, permettent une évaluation de la capacité du canal MIMO. Ces résultats permettent de discuter de l’intégration des techniques MIMO dans des systèmes de communication sans fil

Análisis de prestaciones de un tren mixto viajeros – mercancías propulsado por hidrógeno en la línea Zaragoza – Canfranc Estación

El objetivo es el análisis de prestaciones de un tren mixto para viajeros y mercancías traccionado por motores eléctricos alimentados a través de pilas de combustible con hidrógeno y el estudio de implantación en la línea Zaragoza-Canfranc Estación. Un nuevo concepto de transporte que conjuga: una conexión de alta capacidad y mejora de los tiempos de viaje, utilizando tecnologías en base al hidrógeno que permitirán reducir emisiones contaminantes, impulsando una línea mixta de pasajeros - mercancías que pudiese reactivar la economía de las comarcas.<br /

Utilisation des photos panoramiques pour la compréhension des phénomènes physiques du canal de propagation

International audienceCet article décrit une méthode du canal de propagation. Les directions d'arrivée sont juxtaposées sur des photos panoramiques 3D. L'ensemble appelé radiophoto permet la corrélation entre la mesure du canal et l'environnement. Les phénomènes physiques tels que la réflexion ou la dffraction sont facilement identifiés

Dynamic Pathways for Viral Capsid Assembly

We develop a class of models with which we simulate the assembly of particles into T1 capsid-like objects using Newtonian dynamics. By simulating assembly for many different values of system parameters, we vary the forces that drive assembly. For some ranges of parameters, assembly is facile, while for others, assembly is dynamically frustrated by kinetic traps corresponding to malformed or incompletely formed capsids. Our simulations sample many independent trajectories at various capsomer concentrations, allowing for statistically meaningful conclusions. Depending on subunit (i.e., capsomer) geometries, successful assembly proceeds by several mechanisms involving binding of intermediates of various sizes. We discuss the relationship between these mechanisms and experimental evaluations of capsid assembly processes.Comment: 13 pages, 13 figures. Submitted to Biophys.