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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
431

Controle da tuberculose em contatos intradomiciliares: o papel dos serviços de saúde de Pelotas, RS / Control of tuberculosis in household contacts: the role of health services in Pelotas, RS

Lima, Lilian Moura de 07 October 2011 (has links)
Made available in DSpace on 2014-08-20T13:49:44Z (GMT). No. of bitstreams: 1 LILIAN MOURA DE LIMA.pdf: 1272342 bytes, checksum: e6c136314886322d6aa38853685abd38 (MD5) Previous issue date: 2011-10-07 / Household contacts of index cases tuberculosis have an increased risk of developing the disease due to the closeness and the time duration of exposure to the bacillus. For this reason the evaluation of these individuals is decisive to controlling the disease, since the early diagnosis and timely treatment stop the transmission chain of the disease reflecting on the reduction of incidence rates. To this purpose there are protocols and targets proposed by the World Health Organization in which the health services should be based in the proper evaluation of the contacts. The study aimed investigate the health services that diagnosticate tuberculosis in Pelotas in relation to the service offered to household contacts of the index case. It consists of a descriptive, quantitative and transversal cut study linked to the multicentric project entitled "Delay in the diagnosis of tuberculosis: analysis of causes in different regions of Brazil". The study sample was composed of 85 index cases of tuberculosis interviewed in the origin study in Pelotas and their 163 household contacts. The collection of these data took place between July and December 2009 in the control of tuberculosis program in Pelotas and the collection of medical records has occurred in January 2011 in this same service. It was used the database research of the multicentric study and it was built a database in Excel software with the data from medical records. The analysis of data was performed using descriptive statistics. The results show that attention to tuberculosis in Pelotas need to be rethought with the of involving primary care in the evaluation of household contacts in order to facilitate early diagnosis, appropriate clinical evaluation of contacts and interruption of transmission chain of TB in appropriate time. / Os contatos intradomiciliares dos casos índices de tuberculose têm risco aumentado de desenvolver a doença em virtude da proximidade e do tempo de exposição ao bacilo. Por este motivo a avaliação destes indivíduos é determinante para o controle da doença, já que o diagnóstico precoce e o tratamento oportuno interrompem a cadeia de transmissão da doença repercutindo na redução das taxas de incidência. Para tanto existem protocolos e metas propostos pela Organização Mundial da Saúde, nos quais, os serviços de saúde devem basear-se na avaliação adequada dos contatos. O estudo objetivou investigar os serviços de saúde que fazem o diagnóstico da tuberculose em Pelotas quanto ao atendimento oferecido aos contatos intradomiciliares do caso índice. Constitui-se de um estudo descritivo, quantitativo de corte transversal, vinculado ao projeto multicêntrico intitulado Retardo no diagnóstico da tuberculose: análise das causas nas diferentes regiões do Brasil . A amostra do estudo foi composta por 85 casos índices de tuberculose entrevistados no estudo de origem em Pelotas e seus 163 contatos intradomiciliares. A coleta destes dados deu-se entre julho e dezembro de 2009 no programa de controle da tuberculose de Pelotas e a etapa de coleta do prontuário em janeiro de 2011, neste mesmo serviço. Utilizou-se o banco de dados da pesquisa do estudo multicêntrico e com os dados do prontuário construiu-se um banco no software Excel. A análise dos dados foi realizada por meio da estatística descritiva. Os resultados evidenciam que a atenção a tuberculose em Pelotas necessita ser repensada no intuito de envolver a atenção primária na avaliação dos contatos intradomiciliares, visando facilitar o diagnóstico precoce, a avaliação clínica adequada dos contatos e a interrupção da cadeia de transmissão da TB em tempo oportuno.
432

[en] EFFICIENT SOLUTION OF AN INTEGRAL EQUATION AND ITS APPLICATIONS TO THE PREDICTION OF THE COVERAGE OF CELLULAR SYSTEMS / [pt] SOLUÇÃO EFICIENTE DE UMA EQUAÇÃO INTEGRAL E SUA APLICAÇÃO NA PREVISÃO DA COBERTURA DE SISTEMAS CELULARES

FELIX KORBLA AKORLI 17 April 2006 (has links)
[pt] Neste trabalho, foi desenvolvido um algoritmo para a solução de uma equação integral que possa ser aplicado de forma eficiente na previsão da cobertura de sistemas celulares. Este algoritmo compara-se com o algoritmo proposto originalmente e com a mesma aplicação baseada na técnica de traçado de raios. A técnica de traçado de raios utiliza o método das imagens no traçado dos raios pertencentes a trinta diferentes classes, caracterizadas pela multiplicidade e pelos tipos e ordens das interações com o terreno. Os coeficientes de reflexão e de difração são calculados pelas equações clássicas de Fresnel e pelas equações da Teoria Uniforme da Difração, respectivamente, modificadas para considerar a rugosidade do terreno. Ambos os algoritmos foram aplicados para calcular a intensidade de campo ao longo de um perfil de terreno e em uma região montanhosa do sul do Estado de Minas Gerais. Os resultados são comparados entre si e com os resultados de medidas, quando disponíveis. Esta comparação considera tanto os resultados obtidos quanto os tempos de processamento necessários em ambos os casos. / [en] In this work an algorithm for the solution of an integral equation, which can efficiently be applied to estimate the coverage areaof a cellular system, has been developed. This algorithm is compared with the original proposed algorithm and also woth Ray tracing Techiniques for the same applications. The Ray Tracing Tecniques uses the image Tecnique to trace thirty different classes of rays, which are characterised by multiplicity of the paths and also the nature of graund. The coefficients of reflection and diffraction have been calculeted by using the classical Fresnel and the Uniform Theory of Diffraction equations respectively, and have been modified to include the roufhness of the ground. Both algorithms have been used to calculate the fiels intensity along a land profile and also a mountainous region South comparison takes into consideration the quality of the results as well as the processing time of both algorithms.
433

Ray Tracing on GPU : Performance comparison between the CPU and the Compute Shader with DirectX 11

Persson, Gustav, Udd, Jonathan January 2010 (has links)
The game industry have always looked for rendering techniques that makes the games as good looking and realistic as possible. The common approach is to use triangles built up by vertices and apply many different techniques to make it look as good as possible. When triangles are used to draw objects, there is always edges and those edges often make the objects look less realistic than desired. To reduce these visible edges the amount of triangles for an object have to be increased, but with more triangles more processing power from the graphics cards is needed. Another way to approach rendering is ray tracing which can render an extremely photo realistic image but to the cost of unbearable low performance if you would use it in a realtime application. The reason raytracing is so slow is the massive amount of calculations that needs to be made. In DirectX 11 a few new shaders where announced and one of them were the compute shader, the compute shader allows you to calculate data on the graphics card which is not bound to the pipeline. The compute shader allows you to use the hundreds of cores that the graphic card has and is therefore well suited for a raytracing algorithm. One application is used to see if the hypothesis is correct. A flag is used to define if the application runs on the CPU and the GPU. The same algorithm is used in both versions. Three test where done on each processing unit to confirm the hypothesis. Three more tests where done on the GPU to see how the performance scaled on the GPU depending on the number of rendered objects. The tests proved throughout that the compute shader performs considerably better than the CPU when running our ray tracing algorithm.
434

Development of a prototype taint tracing tool for security and other purposes

Kargén, Ulf January 2012 (has links)
In recent years there has been an increasing interest in dynamic taint tracing of compiled software as a powerful analysis method for security and other purposes. Most existing approaches are highly application specific and tends to sacrifice precision in favor of performance. In this thesis project a generic taint tracing tool has been developed that can deliver high precision taint information. By allowing an arbitrary number of taint labels to be stored for every tainted byte, accurate taint propagation can be achieved for values that are derived from multiple input bytes. The tool has been developed for x86 Linux systems using the dynamic binary instrumentation framework Valgrind. The basic theory of taint tracing and multi-label taint propagation is discussed, as well as the main concepts of implementing a taint tracing tool using dynamic binary instrumentation. The impact of multi-label taint propagation on performance and precision is evaluated. While multi-label taint propagation has a considerable impact on performance, experiments carried out using the tool show that large amounts of taint information is lost with approximate methods using only one label per tainted byte.
435

Modélisation dynamique des canaux MIMO pour les transports ferroviaires / Dynamic modeling of MIMO channels for railway transport

Hairoud, Siham 02 July 2012 (has links)
L'exploitation, le contrôle et la signalisation des systèmes de métros modernes et en particulier les métros sans conducteur, reposent sur deux familles de systèmes de communication radio sans fil : les transmissions vitales pour la signalisation et le contrôle des trains à faible débit et les transmissions non vitales très haut débit pour la vidéo surveillance embarquée, le télé-diagnostic,l'information des clients, etc. Lors de la mise en œuvre de tels systèmes de transmission, l'industriel doit donc garantir à l'exploitant de métro des performances concernant les débits et la qualité de la transmission en termes de perte de paquets d'information. Dès lors, appréhender le comportement du canal de propagation est un élément clé pour prédire et améliorer les performances des systèmes de transmission.L'objectif de ces travaux de thèse est double et concerne :• D'une part, la réduction des temps de calcul d'un simulateur de canal à tracé de rayons 3D qui prédit avec précision le comportement du canal de propagation, mais reste coûteux en temps de calculs pour les simulations dynamiques. Nous proposons dans cette thèse une méthode qui s'appuie sur trois critères de visibilité pour simplifier la description de lagéométrie de l'environnement sans pénaliser la prédiction des paramètres caractéristiques du canal de propagation ;• D'autre part, la mise en œuvre d'un nouveau modèle de canal de propagation MIMO dynamique en tunnel rectiligne de section rectangulaire qui permettra d'optimiser des systèmes de transmission multi antennaires (MIMO) pour des applications de transmissions sans fil pour les métros en tunnel. Ce modèle s'inspire globalement du modèle de canal utilisé / The exploitation, control and signalling systems for metro and especially modern driverless metros, are based on two families of radio communication systems Wireless : vital transmissions for signalling and train control low-flow and nonvital transmissions with very high bandwidth for video-tracking systems, telediagnosis, customer information, etc.. During the implementation ofsuch transmission systems, the industrial must therefore ensure the metro operator performance on throughput and transmission quality in terms of packet loss information. Therefore, understanding the behavior of the propagation channel is a key to predict and improve performance of transmission systems.The aim of this thesis is twin and concerns :• On the one hand, the computation time reduction of a 3D ray tracing simulator that accurately predicts the behavior of the propagation channel, but it is expensive in times of calculation for dynamic simulations. We propose here a new method based on three visibility criteria to simplify the geometry description of the environment without degrading the characteristic parameters prediction of the propagation channel ;• On the other hand, the construction of a new model for MIMO propagation channel dynamics in straight tunnel of rectangular section which will optimize transmission systems multi-antennary (MIMO) applications for wireless transmission in metros tunnel. This model draws broadly from the channel model used in the standard WINNER and is fed by the results extracted from the 3D ray tracing channel simulator. The results obtained in this thesis are encouraging and offer many opportunities.
436

Amélioration de la localisation de défauts dans les circuits digitaux par diagnostic au niveau transistor / Digital IC Physical Defect Localization Improvement through Transistor Level Diagnosis

Sun, Zhenzhou 16 May 2014 (has links)
La croissance rapide dans le domaine des semi-conducteurs fait que les circuits digitaux deviennent de plus en plus complexes. La capacité à identifier la cause réelle d'une défaillance dans un circuit digital est donc critique. Le diagnostic logique est une procédure qui permet de localiser une erreur observée dans un circuit fautif, l'analyse de défaillance peut être ensuite appliquée pour déterminer la cause réelle de cette erreur. Un diagnostic efficace et précis est donc fondamental pour améliorer les résultats de l'analyse de défaillance et augmenter éventuellement le rendement de production."Effet à Cause" et "Cause à Effet" sont deux approches classiques pour le diagnostic logique. Ce diagnostic fournit une liste de suspects au niveau porte logique. Cependant, cette approche n'est pas précise dans le cas où le défaut est localisé à l'intérieur de la cellule logique.Dans cette thèse, nous proposons une nouvelle méthode de diagnostic intra-cell basé sur l'approche "Effet à Cause" pour améliorer la précision de la localisation de défaut au niveau transistor. L'approche proposée utilise l'algorithme CPT (Traçage de chemins critiques) appliqué au niveau transistor. Pour chaque cellule suspecte, nous appliquons un CPT avec les vecteurs de test fautifs. Le résultat obtenu est une liste de suspects préliminaires. Chaque suspect peut être un noeud (G, S, D) de transistor. Par la suite, nous appliquons un CPT avec les vecteurs de test non-fautifs pour minimiser la liste de suspects. La méthode proposée donne la localisation précise du défaut pour une erreur observée. Par ailleurs, la méthode est indépendante du modèle de faute invoqué. / The rapid growth in semiconductor field results in an increasing complexity of digital circuits. The ability to identify the root cause of a failing digital circuit is becoming critical for defect localization. Logic diagnosis is the process of isolating the source of observed errors in a defective circuit, so that a physical failure analysis can be performed to determine the root cause of such errors. Effective and precise logic diagnosis is crucial to speed up the failure analysis and eventually to improve the yield.“Effect-Cause” and “Cause-Effect” are the two classical approaches for logic diagnosis. Logic diagnosis provides a list of gates as suspects. However, this approach may not leads to accurate results in the case of the defect is inside a gate.We propose a new intra-cell diagnosis method based on “Effect-Cause” approach to improve the defect localization accuracy at transistor level. The proposed approach exploits the CPT (Critical Path Tracing) applied at transistor level. For each suspected cell, we apply the CPT for every given failing test vector. The result is a preliminary list of candidates. Each candidate can be a net or a transistor drain, gate or source. After that, we apply the CPT for each passing test vector in order to narrow down the the list of candidates. The proposed method gives precise localization of the root cause of the observed errors. Moreover, it does not require the explicit use of a fault model.
437

Identification du connectome de l'aire 24 du cortex cingulaire antérieur dans le contexte du développement de phénotypes de type anxio-dépressif chez la souris : implication de la voie amygdalo-cingulaire / Identification of the anterior cingulate cortex area 24 in the context of anxiodepressive-like phenotypes development in the mouse : implication of the amygdalo-cingulate pathway

Fillinger, Clémentine 09 June 2017 (has links)
Le cortex cingulaire antérieur (CCA) est une région préfrontale située au centre d’un réseau permettant l’échange d’informations cognitives, motrices, limbiques et viscérales, la plaçant ainsi comme un sujet incontournable dans l’étude de pathologies complexes telles que les troubles anxio-dépressifs. Afin de pouvoir aborder ces pathologies chez la souris, nous avons établi par traçage neuronal le connectome complet des différentes aires composant le CCA. Nous avons ainsi montré qu’une grande majorité des structures de ce connectome communique de manière réciproque avec cette région et que, selon les aires cingulaires, des spécificités de densité d'innervation et de topographie peuvent exister. Ceci suggère des fonctions partagées mais également des rôles plus spécifiques à chaque aire. A partir de ce connectome, nous avons ensuite montré, par une approche optogénétique associée à des tests comportementaux, que l'activation répétée de la projection de l’amygdale au CCA est susceptible d'induire des comportements de type anxio-dépressif chez des souris naïves. Ce travail met donc en évidence le rôle d'une partie du connectome du CCA dans l'établissement des troubles de l'humeur. / The anterior cingulate cortex (ACC) is a prefrontal region located at the center of a network allowing the sharing of cognitive, motor, limbic and visceral information, placing it as an interesting target for the study of complex pathologies like mood disorders. To investigate these diseases in mice, we provided the complete connectome of each ACC areas by a tract-tracing approach. We demonstrated that the majority of structures constituting this connectome are reciprocally connected with the ACC and that some density and topographical connection specificities were observed among cingulate areas. These results potentially suggest some shared functions between cingulate areas, also completed by specific roles inherent to each area. Using this connectome, we demonstrated that the repeated activation of the amygdala projection to the ACC was able to induce anxiodepressive-like behaviors in naïve mice, by using optogenetics combined with behavioral tests. This study highlights for the first time the implication of a portion of the ACC connectome in the establishment of mood disorders.
438

Detection of Chlamydia trachomatis and Mycoplasma genitalium by genetic and serological methods

Jurstrand, Margaretha January 2006 (has links)
Chlamydia trachomatis infections are associated with a spectrum of clinical diseases including urethritis, prostatitis and epididymitis among men and cervicitis and pelvic inflammatory disease (PID), with an increased risk of infertility and ectopic pregnancy (EP), among women. In the search for other pathogens causing urethritis, Mycoplasma genitalium was isolated from urethral specimens from two men with acute urethritis (1980). Mycoplasma bacteria are extremely difficult to isolate by culture, and clinical studies have been possible only after the advent of the first PCR-based detection method. M. genitalium has been found to be associated with lower genital tract infections in both men and women. Finding evidence for a connection between M. genitalium and upper genital tract infections in women is still of major importance. The aim in papers I and II was to develop a PCR method for genetic characterization of clinical C. trachomatis isolates by sequence analysis of the omp1 gene, and to study the distribution of genotypes within sexual networks and determine if genotyping would improve partner notification. The method was used to determine the genotypes of C. trachomatis in 237 positive urogenital and/or urine specimens from men and women attending the STDClinic in Örebro during one year. Sequence analysis of the omp1 gene revealed that the most prevalent genotypes corresponded to C. trachomatis serovar E (47%), followed by F (17%), and K (9%). There were 161 networks found and specimens were sequenced from at least two patients in 47 networks. In seven of these 47 networks there were discrepant genotypes. In the largest network comprising 26 individuals two different C. trachomatis genotypes were found, and one partner had urethritis due to a Mycoplasma genitalium infection but was C. trachomatis negative. The need for a new method for M. genitalium DNA detection was one reason for study III. An existing conventional PCR protocol for detection of M. genitalium DNA was further developed into a real-time PCR (RT-PCR) with hybridisation probes. In order to evaluate the RT-PCR assay with clinical material, specimens from 398 men and 301 women attending the STD Clinic in Örebro were analysed, using the RT-PCR assay, and also by the well established conventional PCR in Copenhagen. Using the conventional PCR method as “gold standard”, the sensitivity for the RT-PCR assay was 72.2% and 68.2% and the specificity was 99.7% and 98.6%, respectively, in urogenital specimens from men and women. The aim in paper IV was to adapt a Triton X-114 extracted Lipid-Associated Membrane Protein (LAMP) Enzyme Immuno Assays (EIA) method to detect antibodies against M. genitalium and to evaluate the association between M. genitalium and PID and EP, using sera sampled in Örebro during the 1980s, and also to compare the number of sera having M. genitalium antibodies against those having C. trachomatis antibodies, using a commercial anti- Chlamydia trachomatis EIA assay. No statistical significant association could be demonstrated between M. genitalium antibodies and PID or EP in our serum material. However, a slight trend toward association was found when focusing on younger individuals. Antibodies against C. trachomatis were found to be significantly associated with PID and EP.
439

Experimental and numerical study of atmospheric turbulence and dispersion in stable conditions and in near field at a complex site / Etude expérimentale et numérique de la turbulence et de la dispersion atmosphériques en conditions stables et en champ proche sur un site complexe

Wei, Xiao 24 March 2016 (has links)
Un programme expérimental a été conçu afin d'étudier la dispersion des polluants sur un terrain complexe avec un accent mis sur des conditions stables qui restent délicates pour la modélisation numérique. Ce programme expérimental est mené sur le site du SIRTA dans la banlieue sud de Paris et consiste à mesurer en champ proche la turbulence et la dispersion des polluants. L'objectif de ce programme est de caractériser la structure fine de la turbulence et de la dispersion associée par des mesures à haute résolution temporelle et spatiale. Ensuite, ces mesures permettent de valider et d'améliorer la qualité de simulations CFD pour la turbulence et la dispersion sur un site fortement hétérogène. Le dispositif instrumental comprend 12 anémomètres ultrasoniques mesurant en continu la vitesse du vent et la température à 10 Hz, et 6 détecteurs à photo-ionisation (PID) mesurant la concentration de gaz à 50 Hz pendant des essais de traçage. Plusieurs périodes d’observations intensives (POIs) avec des rejets de gaz ont été réalisées depuis Mars 2012.Tout d'abord, une étude détaillée de l'écoulement du vent sur le site est réalisée, car l’écoulement doit être caractérisé et correctement simulé avant de simuler la dispersion des polluants. Cette étude est basée sur deux ans de mesures en continu et sur les mesures acquises durant les POIs. La forte anisotropie de la turbulence dans la couche de surface est caractérisée à l’aide du calcul des variances, des échelles de longueur intégrales et des spectres des trois composantes de la vitesse du vent. La propagation des structures turbulentes entre les capteurs est caractérisée en utilisant les corrélations de vitesse. Les spectres de vitesse montrent plusieurs pentes dans différentes zones de fréquence. En outre, l’analyse des données montre l’impact de l'hétérogénéité du terrain sur les mesures. La forêt au nord du site expérimental modifie la vitesse et la direction du vent pour un grand secteur nord. Il induit un fort cisaillement de la direction du vent et une décélération en dessous de la hauteur de la forêt. Les simulations numériques sont effectuées avec le code de CFD Code_Saturne en mode RANS avec une fermeture k-ε adaptée pour les écoulements atmosphériques et un modèle de canopée pour la forêt. Ces simulations reproduisent correctement les caractéristiques de l'écoulement moyen sur le site des mesures, en particulier l'impact de la forêt pour les différentes directions du vent et pour la stratification neutre et stable. Les résultats de simulation montrent aussi le cisaillement de direction du vent et l’augmentation de l’énergie cinétique turbulente induits par la forêt. Une étude de sensibilité montre que ces effets sur l'écoulement s’accentuent quand la densité foliaire augmente. L’étude de dispersion est réalisée pour plusieurs POIs. L’analyse des données de concentration montre la cohérence avec les mesures de campagnes précédentes réalisées dans des zones proches de la source. Les fluctuations de concentrations sont caractérisées à travers les séries temporelles, l'histogramme et l'analyse statistique des concentrations. Une zone inertielle peut également être identifiée dans les spectres de concentration. Ensuite, la dispersion des polluants est modélisée par les équations de transport pour la concentration et sa variance. La concentration moyenne est globalement en bon accord avec les mesures pour toutes les POIs étudiées. L’accord avec les mesures sur la position du maximum de concentration dépend de la précision de la rotation du vent simulée en-dessous de la hauteur de la forêt. Les fluctuations de concentration obtenues dans les simulations semblent être affectées de manière significative par la condition initiale et la modélisation du terme de dissipation. Une étude de sensibilité à la paramétrisation est ensuite présentée / An experimental program has been designed in order to study pollutants dispersion at a complex site with a focus on stable conditions, which are still challenging for numerical modelling. This experimental program is being conducted at the SIRTA site in a southern suburb of Paris and consists in measuring, in near field, the turbulence and the pollutants dispersion. The aim of this program is to characterize the fine structure of turbulence and associated dispersion through high temporal and spatial resolution measurements. Then, these measurements allow to validate and improve the performance of CFD simulation for turbulence and dispersion in a heterogeneous field. The instrumental set up includes 12 ultrasonic anemometers measuring continuously wind velocity and temperature at 10 Hz, and 6 photo-ionization detectors (PIDs) measuring gas concentration at 50 Hz during tracer tests. Intensive observations periods (IOPs) with gas releases have been performed since March 2012.First of all, a detailed study of flow on the site is made, because it must be characterised and properly simulated before attempting to simulate the pollutants dispersion. This study is based on two years of continuous measurements and on measurements performed during IOPs. Turbulence strong anisotropy in the surface layer is characterized by calculating variances, integral length scales and power spectra of the three wind velocity components. Propagation of turbulent structures between sensors has been characterized with velocity correlations. Energy spectra show several slopes in different frequency regions. Also, data analyses show impact of terrain heterogeneity on the measurements. The forest to the north of experimental field modifies wind velocity and direction for a large northerly sector. It induces a strong directional wind shear and a wind deceleration below the forest height. Numerical simulations are carried out using the CFD code Code_Saturne in RANS mode with a standard k-ε closure adapted for atmospheric flows and a canopy model for the forest. These simulations are shown to reproduce correctly the characteristics of the mean flow on the measurements site, especially the impact of the forest for different wind directions, in both neutral and stable stratification. Simulations results also show the directional wind shear and the turbulent kinetic energy increase induced by the forest. A sensitivity study has been made for various values of forest density and shows that the typical features of canopy flow become more pronounced as canopy density increases. Pollutants dispersion study are made for several IOPs. Concentration data analysis shows a consistency with previous measurements made in a near-source region where the plume scale is smaller than the large-scale turbulence eddies. Concentration fluctuations are characterized through concentration time series, histogram and statistical analysis. The internal subrange can be observed in the concentration spectra. Next, pollutants dispersion are modelled by transport equations for concentration and its variance. The mean concentrations show a good agreement with measurements in values for all the IOPs studied, except that the position of the concentration peak depends on the accuracy of simulated wind rotation below the forest height. The concentration fluctuations obtained from simulations seem to be affected significantly by the initial condition and the modelling of the dissipation term. A sensitivity study to the parameterisation is then presented
440

Unfavorable environmental conditions: Consequences for microbial metabolism and C stabilization in soil

Bore, Ezekiel 14 November 2017 (has links)
No description available.

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