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Estudo da refletância e sua influência no comportamento térmico de tintas refletivas e convencionais de cores correspondentes.; Influence of reflectivity on the thermal behavior of color-matched reflective and conventional paints.

Ikematsu, Paula
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 30/11/2007 PT
Relevância na Pesquisa
37%
O principal objetivo deste estudo foi avaliar a refletância e sua influência no comportamento térmico de tintas refletivas e tintas convencionais aplicadas em telhas de fibrocimento para cobertura de habitações brasileiras. Foram realizados ensaios em laboratório de determinação de cor e de brilho por medida instrumental e determinação da refletância por análise espectrofotométrica em películas. Para o estudo do comportamento térmico foram realizados ensaios de simulação em laboratório com corpos-de-prova expostos à radiação infravermelha emitida por lâmpadas e de exposição à radiação solar em campo através de protótipos com monitorização da temperatura durante as exposições. Os resultados dos ensaios de determinação de cor e de brilho mostraram que as pinturas refletivas e convencionais realmente apresentaram cores correspondentes. Os resultados de refletância mostraram que as pinturas refletivas apresentaram valores de refletância superiores em relação às tintas convencionais, o que foi comprovado pela temperatura medida nos ensaios de exposição à radiação infravermelha e radiação solar. A conclusão do estudo é que as tintas refletivas têm potencial para redução da temperatura superficial da telha de fibrocimento e que é necessária uma continuidade do estudo de durabilidade e do desempenho térmico de tintas refletivas coloridas.; The main purpose of this study was to investigate the effect of reflective colored paints and conventional colored paints applied on fiber cement corrugated roofing sheets...

Characterization of tin oxide based sol-gel coatings on borosilicate glasses by X-ray reflectivity

Rizzato, A. P.; Santilli, C. V.; Pulcinelli, S. H.
Fonte: Kluwer Academic Publ Publicador: Kluwer Academic Publ
Tipo: Artigo de Revista Científica Formato: 811-816
ENG
Relevância na Pesquisa
36.86%
The X-ray reflectivity technique was applied in the study of tin oxide films deposited by sol-gel dip-coating on borosilicate glasses. The influence of the withdrawal speed and temperature of thermal treatment on the film structure was analyzed. We have compared the thermal evolution of the density and the shrinkage of the films with these properties measured for the monolithic xerogel by helium picnometry and thermomechanical analysis. In agreement with the Landau-Levich model, the layer thickness increases by increasing the withdrawal speed. Nevertheless, it decreases with the increase of the thermal treatment temperature, due to the densification process. The values of apparent density are smaller than the skeletal density, which shows that the films are porous. The comparison between the film and the monolith indicates that shrinkage during firing is anisotropic, occurring essentially perpendicular to the coating surface.

A radar reflectivity-runoff model for use in flood warning

Trovati, L. R.; Mattos, A.
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Artigo de Revista Científica Formato: 471-482
ENG
Relevância na Pesquisa
37.17%
This model connects directly the radar reflectivity data and hydrological variable runoff. The catchment is discretized in pixels (4 Km × 4 Km) with the same resolution of the CAPPI. Careful discretization is made so that every grid catchment pixel corresponds precisely to CAPPI grid cell. The basin is assumed a linear system and also time invariant. The forecast technique takes advantage of spatial and temporal resolutions obtained by the radar. The method uses only the measurements of the factor reflectivity distribution observed over the catchment area without using the reflectivity - rainfall rate transformation by the conventional Z-R relationships. The reflectivity values in each catchment pixel are translated to a gauging station by using a transfer function. This transfer function represents the travel time of the superficial water flowing through pixels in the drainage direction ending at the gauging station. The parameters used to compute the transfer function are concentration time and the physiographic catchment characteristics. -from Authors

Structure of Magainin and Alamethicin in Model Membranes Studied by X-Ray Reflectivity

Li, C.; Salditt, T.
Fonte: Biophysical Society Publicador: Biophysical Society
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
27.1%
We have investigated the structure of lipid bilayers containing varied molar ratios of different lipids and the antimicrobial peptides magainin and alamethicin. For this structural study, we have used x-ray reflectivity on highly aligned solid-supported multilamellar lipid membranes. The reflectivity curves have been analyzed by semi-kinematical reflectivity theory modeling the bilayer density profile ρ(z). Model simulations of the reflectivity curves cover a large range of vertical momentum transfer qz, and yield excellent agreement between data and theory. The structural changes observed as a function of the molar peptide/lipid concentration P/L are discussed in a comparative way.

A suspended act: increased reflectivity and gender-dependent electrophysiological change following Quadrato Motor Training

Ben-Soussan, Tal Dotan; Berkovich-Ohana, Aviva; Glicksohn, Joseph; Goldstein, Abraham
Fonte: Frontiers Media S.A. Publicador: Frontiers Media S.A.
Tipo: Artigo de Revista Científica
Publicado em 03/02/2014 EN
Relevância na Pesquisa
27.1%
Quadrato Motor Training (QMT) is a specifically-structured walking meditation, aimed at improving reflectivity and lowering habitual thought and movement. Here we set out to examine the possible effect of QMT on reflectivity, employing the Hidden Figures Test (HFT), which assesses both spatial performance (measured by correct answers) as well as reflectivity (interpolated from correct answers and reaction time). In the first study (n = 24, only females), we showed that QMT significantly improves HFT performance, compared to two groups, controlling for cognitive or motor aspects of the QMT: Verbal Training (identical cognitive training with verbal response) and Simple Motor Training (similar motor training with reduced choice requirements). These results show that QMT improves HFT performance above the pre-post expected learning. In the second study, building on previous literature showing gender-dependent effects on cognitive performance, we conducted a preliminary pilot examining gender-dependent effect of training on reflectivity and its electrophysiological counterparts. EEG analyses focused on theta, alpha and gamma coherence. HFT performance and resting-state EEG were measured in 37 participants (20 males), using a within-subject pre-post design. Following training...

Regional Gray Matter Density Associated with Cognitive Reflectivity–Impulsivity: Evidence from Voxel-Based Morphometry

Yokoyama, Ryoichi; Nozawa, Takayuki; Takeuchi, Hikaru; Taki, Yasuyuki; Sekiguchi, Atsushi; Nouchi, Rui; Kotozaki, Yuka; Nakagawa, Seishu; Miyauchi, Carlos Makoto; Iizuka, Kunio; Shinada, Takamitsu; Yamamoto, Yuki; Hanawa, Sugiko; Araki, Tsuyoshi; Hashizum
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
Publicado em 24/03/2015 EN
Relevância na Pesquisa
27.17%
When faced with a problem or choice, humans can use two different strategies: “cognitive reflectivity,” which involves slow responses and fewer mistakes, or “cognitive impulsivity,” which comprises of quick responses and more mistakes. Different individuals use these two strategies differently. To our knowledge, no study has directly investigated the brain regions involved in reflectivity–impulsivity; therefore, this study focused on associations between these cognitive strategies and the gray matter structure of several brain regions. In order to accomplish this, we enrolled 776 healthy, right-handed individuals (432 men and 344 women; 20.7 ± 1.8 years) and used voxel-based morphometry with administration of a cognitive reflectivity–impulsivity questionnaire. We found that high cognitive reflectivity was associated with greater regional gray matter density in the ventral medial prefrontal cortex. Our finding suggests that this area plays an important role in defining an individual’s trait associated with reflectivity and impulsivity.

Wetting Behavior at the Free Surface of a Liquid Gallium–Bismuth Alloy: An X-ray Reflectivity Study Close to the Bulk Monotectic Point

Huber, P.; Shpyrko, O. G.; Pershan, Peter S.; Tostmann, H.; DiMasi, E.; Ocko, B. M.; Deutsch, M.
Fonte: Elsevier Publicador: Elsevier
Tipo: Artigo de Revista Científica
EN_US
Relevância na Pesquisa
36.86%
We present X-ray reflectivity measurements from the free surface of a liquid gallium–bismuth alloy (Ga–Bi) in the temperature range close to the bulk monotectic temperature (T_{mono})=222(^circ)C. Our measurements indicate a continuous formation of a thick wetting film at the free surface of the binary system driven by the first order transition in the bulk at the monotectic point. We show that the behavior observed is that of a complete wetting at a tetra point of solid–liquid–liquid–vapor coexistence.; Engineering and Applied Sciences

Correlação entre o fator de refletividade do radar e a vazão no rio Mundaú; Correlation between reflectivity factor and flow in the Mundaú river

Barros, Adriano Aubert Silva
Fonte: Universidade Federal de Alagoas; BR; Processos de superfície terrestre; Programa de Pós-Graduação em Meteorologia; UFAL Publicador: Universidade Federal de Alagoas; BR; Processos de superfície terrestre; Programa de Pós-Graduação em Meteorologia; UFAL
Tipo: Dissertação Formato: application/pdf
POR
Relevância na Pesquisa
37.1%
This application aims to identify a possible correlation between the reflectivity factor signal RADAR Weather Radar System of Alagoas (SIRMAL), with the flow of the Rio Mundaú, data obtained fromthe Hydrological Station National Water Agency (ANA) in BoaFortuna, Rio Largo, Alagoas. What is required is a remote monitoring and continuous rate of flow, at one point the river basin Mundaú in order to predict possible flood waves. The floods in the river Mundaú are recurrent, having brought great losses in material resources and human lives for decades, their monitoring is of fundamental importance for better planning and management of these resources. For this we constructed a computer code in object-oriented language, Object Pascal. The program reads the image in jpeg format, generated and provided by SIRMAL on his Internet site, spatially integrates all the values of reflectivity of the microwave pulse on the watershed, determining the volume and then precipitated considered high rainfall area on the Watershed River Mundaú. This value is associated with the reflective state of the basin, at a given time, indicates the amount of precipitated water in the basin for a given period. The high rainfall is related to precipitation over the basin and consequently the flow in river. To verify the correlation with the flow...

Using the Video Lookup Table for Reflectivity Calculations: Specific Techniques and Graphic Results

Bass, Daniel H.
Fonte: University of Rochester. Computer Science Department. Publicador: University of Rochester. Computer Science Department.
Tipo: Relatório
ENG
Relevância na Pesquisa
37.1%
Sloan and Brown [2] have shown that the video lookup table can be used to provide fast and flexible changes to a raster graphic display without changing the image memory contents. By storing encoded surface normal vectors and using the video lookup table to perform reflectivity calculations, the surface may be rapidly displayed under a wide range of lighting and reflectivity conditions. However, there are certain drawbacks. First, quantizing the surface normals produces artifacts in the final image unlike those resulting from the usual approach of quantizing the surface brightness. Second, the lighting effects must be independent of object position, and so shadowing cannot be done with this method. Third, the process is still not quite fast enough to allow real-time rotating lights. Results from the use of this method are shown in photographs of the display of several objects under different lighting, reflectivity conditions, and surface normal quantization schemes.

Valida????o da assimila????o de dados na infer??ncia da refletividade de um radar com sistema MM5; Validation of data assimilation in the inference of reflectivity of a radar with MM5 system

SILVA, Gustavo Leite da
Fonte: Universidade Federal de Pelotas; Meteorologia; Programa de P??s-gradua????o em Meteorologia; UFPel; BR Publicador: Universidade Federal de Pelotas; Meteorologia; Programa de P??s-gradua????o em Meteorologia; UFPel; BR
Tipo: Dissertação Formato: application/pdf
POR
Relevância na Pesquisa
36.86%
On certain occasions the State of Rio Grande do Sul is affected by atypical weather systems events which are among the category of mesoscale phenomena. The inability of large scale numerical models to appropriately simulate several localized effects, which occurs over the most varied regions, associated to the fast increase of computational resources, it is facilitating and increasingly inducing the use of mesoscale models to improve the knowledge on those anomalous and severe events and even for use as a necessary and indispensable operational tool. The skill of mesoescala model to proceed in providing precipitation forecasts, in space and time scale compatible with to those of a Doppler meteorological radar, it is implemented the whole system of mesoscale modeling that constitutes the MM5. The occurrence of the relatively severe precipitation event, in the area close to the city of Cangu??u / RS, on January 11, 2008 was arbitrarily selected to evaluate the model skill - in inferring the reflectivity of the meteorological radar, installed in Cangu??u / RS proceeding with conventional data assimilations, PCA (Processing With Assimilation) and PSA (Processing Without Assimilation), as well an approach to the analysis of the thermo-hydrodynamics and synoptic conditions.; Em certas ocasi??es o Estado do Rio Grande do Sul ?? assolado por sistemas meteorol??gico com manifesta????es atmosf??ricas at??picas e que se enquadram entre os fen??menos de mesoescala. A impossibilidade de modelos num??ricos de grande escala simularem adequadamente diversos efeitos localizados...

O processo de reflexividade promovido pela pesquisa na formação inicial de professores; The reflectivity process encouraged by research in the teacher's initial formation

Rita Buzzi Rausch
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 17/04/2008 PT
Relevância na Pesquisa
37.17%
A formação inicial de professores no curso de Pedagogia da Universidade Regional de Blumenau - FURB - tem a prática investigativa como abordagem metodológica do fazer docente, constituindo-se em espaço de constante aprendizagem e construção reflexiva do professor. Nesta perspectiva, incluiu, no currículo do curso, o Trabalho de Conclusão de Curso que possibilita a inserção do acadêmico à pesquisa científica. Neste contexto e a partir da indagação - como se constitui o processo de reflexividade do acadêmico/professor, em sua formação inicial, por meio da pesquisa do TCC - foi realizada esta pesquisa, cujo objetivo geral foi compreender o processo de reflexividade de acadêmicos de Pedagogia por meio da análise dos níveis de lógica reflexiva promovidos na realização do TCC. Participaram desta pesquisa sete acadêmicas cujos estudos foram orientados pela pesquisadora. Os momentos de orientação foram gravados e transcritos e a apresentação oral da pesquisa videogravada. Foi solicitado que cada acadêmica registrasse, também, em portfólios reflexivos, todo o processo vivenciado nessa atividade. Utilizamo-nos do software Qualiquantisoft para organizar os discursos orais e escritos das acadêmicas em expressões-chave e idéias centrais. Analisamos...

Photoreceptor Inner and Outer Segment Junction Reflectivity after Vitrectomy for Macula-Off Rhegmatogenous Retinal Detachment

Kaluzny, Jakub J.; Sikorski, Bartosz L.; Czajkowski, Grzegorz; Burduk, Mateusz; Kaluzny, Bartlomiej J.; Stafiej, Joanna; Malukiewicz, Grazyna
Fonte: Hindawi Publishing Corporation Publicador: Hindawi Publishing Corporation
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
27.26%
Purpose. To evaluate the spatial distribution of photoreceptor inner and outer segment junction (IS/OS) reflectivity changes after successful vitrectomy for macula-off retinal detachment (PPV-mOFF) using spectral domain optical coherence tomography (SdOCT). Methods. Twenty eyes after successful PPV-mOFF were included in the study. During a mean follow-up period of 15.3 months, SdOCT was performed four times. To evaluate the IS/OS reflectivity a four-grade scale was used. Results. At the first follow-up visit the IS/OS had very similar reflectivity in entire length of the central scan with total average value of 1,05. At the second visit the most significant increase of the reflectivity was observed in temporal and nasal parafovea with average values of 2,17 and 2,22, respectively. The third region of increased reflectivity of an average value of 2,33 appeared during the third follow-up visit and was located in the foveola. At the last follow-up visit in entire central cross section the IS/OS reflectivity exceeded grade 2 reaching the highest average values in nasal and temporal parafovea and foveola. Conclusions. A gradual increase of the IS/OS reflectivity was observed in eyes after PPV-mOFF. The process is not random and starts independently in the peripheral and central part of the macula which may be attributed to the variable regenerative potential of cones and rods.

Small Atomic displacements Recorded in Bismuth by the Optical Reflectivity of Femtosecond Laser-Pulse Excitations

Boschetto, David; Gamaly, Eugene G; Rode, Andrei V; Glijer, D. G.; Luther-Davies, Barry; Garl, T.; Albert, O.; Rousse, Antoine; Etchepare, J.
Fonte: American Physical Society Publicador: American Physical Society
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
36.86%
Subtle atomic motion in a Bi crystal excited by a 35 fs-laser pulse has been recovered from the transient reflectivity of an optical probe measured with an accuracy of 10-5. Analysis shows that a novel effect reported here-an initial negative drop in refl

A versatile simulator for specular reflectivity study of multi-layer thin films

Gayen, Sirshendu
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
27.17%
A versatile X-ray/neutron reflectivity (specular) simulator using LabVIEW(National Instruments Corp.) for structural study of a multi-layer thin film having any combination, including the repetitions, of nano-scale layers of different materials is presented here (available to download from the link provided at the end of the paper). Inclusion of absorption of individual layers, inter-layer roughnesses, background counts, beam width, instrumental resolution and footprint effect due to finite size of the sample makes the simulated reflectivity close to practical one. The effect of multiple reflection is compared with simulated curves following the exact dynamical theory and approximated kinematical theory. The applicability of further approximation (Born theory) that the incident angle does not change significantly from one layer to another due to refraction is also considered. Brief discussion about reflection from liquid surface/interface and reflectivity study using polarized neutron are also included as a part of the review. Auto-correlation function in connection with the data inversion technique is discussed with possible artifacts for phase-loss problem. An experimental specular reflectivity data of multi-layer erbium stearate Langmuir-Blodgett (LB) film is considered to estimate the parameters by simulating the reflectivity curve.

A method to measure the mirror reflectivity of a prime focus telescope

Mirzoyan, R.; Garczarczyk, M.; Hose, J.; Paneque, D.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 08/03/2007
Relevância na Pesquisa
27.17%
We have developed a method to measure the mirror reflectivity of telescopes. While it is relatively easy to measure the local reflectivity of the mirror material, it is not so straightforward to measure the amount of light that it focuses in a spot of a given diameter. Our method is based on the use of a CCD camera that is fixed on the mirror dish structure and observes simultaneously part of the telescope's focal plane and the sky region around its optical axis. A white diffuse reflecting disk of known reflectivity is fixed in the telescopes focal plane. During a typical reflectivity measurement the telescope is directed to a selected star. The CCD camera can see two images of the selected star, one directly and another one as a spot focused by the mirror on the white disk. The ratio of the reflected starlight integrated by the CCD from the white disk to the directly measured one provides a precise result of the product of (mirror area x mirror reflectivity).; Comment: This method was first presented as a poster at the Cherenkov 2005 meeting "Towards a Network of Atmospheric Cherenkov Detectors VII" in April 2005, Palaiseau, France. Accepted by Astroparticle Physics

Origin of Periodic Modulations in the Transient Reflectivity Signal at Cryogenic Temperatures

Khan, Salahuddin; Chari, Rama; Jayabalan, J.; Pal, Suparna; Sharma, T. K.; Sagar, A. K.; Ansari, M. S.; Kush, P. K.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 28/08/2012
Relevância na Pesquisa
27.22%
Periodic modulations that appear in the low-temperature transient reflectivity signal of a GaAsP/AlGaAs single quantum well is studied. Similar anomalous oscillations are also observed in layered manganite [K. Kouyama et.al. J. Phys. Soc. Jpn. 76:123702(1-3), 2007]. We show that such periodic modulations are caused by changes in the linear reflectivity of the sample during transient reflectivity measurements. Studied carried out on reflectivity of different materials under identical conditions shows that these modulations on the true transient reflectivity signal are caused by condensation of residual gases on the surface of quantum well. Methods to obtain reliable transient reflectivity data are also described.

Relative contribution of temperature and salinity to ocean acoustic reflectivity

Sallarès, Valentí; Biescas, Berta; Buffett, Grant; Carbonell, Ramón; Dañobeitia, Juan José; Pelegrí, Josep Lluís
Fonte: American Geophysical Union Publicador: American Geophysical Union
Tipo: Artículo Formato: 8985 bytes; application/pdf
ENG
Relevância na Pesquisa
37.1%
6 pages, 3 figures; Marine seismic data display laterally coherent reflectivity from the water column that is attributed to fine-scale oceanic layering. The amplitude of the different reflections is the expression of acoustic impedance contrasts between neighbouring water masses, and therefore water reflectivity maps the ocean's vertical sound speed and density (i.e., temperature and salinity) variations. Here we determine the relative contribution of each parameter by computing the temperature and salinity partial derivatives of sound speed and density, and using them to estimate reflection coefficients from a real oceanographic dataset. The results show that the mean contribution of density variations is 5–10%, while 90–95% is due to sound speed variations. On average, 80% of reflectivity comes from temperature contrasts. Salinity contribution averages 20%, but it is highly variable and reaches up to 40% in regions prone to diffusive convection such as the top of the Mediterranean Undercurrent in the Gulf of Cadiz; This work is part of the EU-FP6 funded GO project (NEST-2003-1 FP6015603), and the data set used here was acquired in the framework of this project. It has also been supported by the Consejo Superior de Invetigaciones Científicas (CSIC) through GEOCEAN PIF Project 200530f081; Peer reviewed

An X-ray reflectivity study of evaporation-induced self-assembled titania-based films

Henderson, Mark; Gibaud, Alain; Bardeau, Jean-Francois; White, John
Fonte: Royal Society of Chemistry Publicador: Royal Society of Chemistry
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
37.17%
X-Ray reflectivity was used to monitor the structural development of a titania-based film at the solid/air interface by evaporation-induced self-assembly (EISA). A nonionic poly(ethylene oxide)-based surfactant, Brij 58, was used as the template and titanium chloride as the inorganic precursor. The reflectivity pattern, film thickness and refractive index were shown to be dependent on film deposition method, whether by casting or by dip-coating onto a silicon wafer, the Brij 58 TiO2 ratio and the relative humidity. At Brij 58 contents of 40 wt%, the reflectivity profile displayed only a single diffraction peak. At 70 wt% Bragg diffraction indicated a lamellar ordering of film components. Modelled reflectivity data suggested a 1060 Å thick film that comprised 17 layers of alternating surfactant and titania with a d spacing of about 60 Å. The effect of relative humidity on film structure was explored.

Transient Reflectivity of Gallium Films Induced by Femtosecond Laser

Gamaly, Eugene G; Rode, Andrei V; Uteza, O; Samoc, Marek; Luther-Davies, Barry
Fonte: Elsevier Publicador: Elsevier
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
37.1%
The transient reflectivity of gallium films induced by 150fs laser pulses has been studied by the pump-probe technique at the pump intensities of 109-1012W/cm2. The time-resolved reflectivity rise of the femtosecond probe in the first 1-4ps after the pump pulse excitation depends strongly on the pump pulse intensity. We demonstrate that the transient electron-phonon collision rate extracted from the reflectivity data is a strong function of the temperature, and thus the laser intensity. This collision rate is drastically different from that observed under equilibrium conditions. The scenario for the microscopic kinetics of the phase transition on the femtosecond time scale is discussed, and new experiments for observation of time-resolved optical properties are proposed.

Simulation of high impact convective events over Indian region by ARPS model with assimilation of Doppler Weather Radar radial velocity and reflectivity

SRIVASTAVA,KULDEEP; ROY BHOWMIK,S. K.; SEN ROY,S.; THAMPI,S. B.; REDDY,Y. K.
Fonte: Centro de Ciencias de la Atmósfera, UNAM Publicador: Centro de Ciencias de la Atmósfera, UNAM
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2010 EN
Relevância na Pesquisa
36.86%
In this paper, impact of assimilation of Indian Doppler Weather Radar (DWR) data has been assessed by numerical weather prediction system (ARPS) at 9 km horizontal resolution. The radial velocity and reflectivity observations from two DWR stations namely, Chennai (Lat. 13.0° N and Long. 80.0° E) and Machilipatnam (Lat. 16.5° N and Long. 81.3° E) are assimilated using the ARPS Data Assimilation System (ADAS) and cloud analysis scheme of the model. Two case studies selected are 1) Bay of Bengal Tropical Cyclone Ogni of October 2006 and 2) A local thunderstorm event of 5 June 2009 over the southeast parts of India. The study shows that the model at 9 km resolution with the assimilation of DWR observations (Chennai) could simulate mesoscale features suchas: number of cells, spiral rain band structure, location of the center, strengthening of the lower tropospheric winds and northerly movement of the small size cyclonic storm in the analysis as well as in the forecasts. The model with DWR assimilation could retain the intensity of the cyclone up to 6 hours of forecasts. Thereafter the cyclone showed a weakening trend when it was drifting away from the radar site. In case of thunderstorm, the model with the DWR assimilation could capture the convective precipitation in the right location. The DWR assimilation could realistically reproduce the development process and south-westward movement of thunderstorm cells.