Investigations on PVP/Y3BO6:Eu3+, a red Luminescent composite for lighting devices based on near UV-LEDs

This work deals with a red phosphor. Y3BO6:Eu3+, and its corresponding poly(N-vinylpyrrolidone) (PVP)/Y3BO6:Eu3+ luminescent composite film suitable for applications in the next generation of Hg-free lamps based on near ultraviolet (UV) light emitting diodes (LEDs). Well crystallized samples of Y3BO6 powders with the Eu3+ content up to 20 mol% were prepared by the Pechini method. After structural, morphological and optical characterization, the best doping rate of Eu3+ in the matrix was determined to be 15 mol%. This optimal powder, which is highly friable, was easily ground into fine particles and homogeneously dispersed into a PVP polymer solution to give rise to a polymer phosphor composite. Structural and optical features of the composite film have been studied and compared to those of a pristine PVP film and Y3BO6:Eu3+ powder. All the characterization (XRD, SAXS, luminescence...) proved that the red phosphor particles are well incorporated into the polymer composite film which exhibited the characteristic red emission of Eu3+ under UV light excitation. Furthermore, photostability of the polymer/phosphor composite film under UV-LED irradiation was evaluated from exposure to accelerated artificial photoageing at wavelengths above 300 nm.

Challenges and opportunities for knowledge organization at the intersection with information technologies

In this paper we study the intersection of Knowledge Organization with Information Technologies and the challenges and opportunities for Knowledge Organization experts that, in our view, are important to be studied and for them to be aware of. We start by giving some definitions necessary for providing the context for our work. Then we review the history of the Web, beginning with the Internet and continuing with the World Wide Web, the Semantic Web, problems of Artificial Intelligence, Web 2.0, and Linked Data. Finally, we conclude our paper with IT applications for Knowledge Organization in libraries, such as FRBR, BIBFRAME, and several OCLC initiatives, as well as with some of the challenges and opportunities in which Knowledge Organization experts and researchers might play a key role in relation to the Semantic Web.

Complexity and information technologies: an ethical inquiry into human autonomous action

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Iluminação de exteriores utilizando tecnologia LED: estudo de caso

This Graduate Work aims to exhibit the analyze of the applicability of LED technology in a real outdoor lighting situation, and this project’s illumination solution is compared with the initial proposal, the sodium vapor lamps. What is studied is an outdoor area, like the roads and parking lots of a plant. A light planning software is used for this comparison, and the results are displayed instantly, allowing rapid analysis of the project through a simulation. The medium illuminance is the same in both solutions for this case study and minimum rates set as standard were observed then the analysis are appropriate in this project. Various aspects are considered in order to obtain a comprehensive analysis of this project, such as economic, environmental and quality of lighting. LED technology in outdoor lighting is presented in its infancy, but promising. Solid state lamps show great advantages when compared with other technologies, such as discharge lamps, however there are some disadvantages tied to new products that are expected to be overcome with technological development and increased production

Estudo da viabilidade técnica/econômica no aumento da eficiência energética sustentável aplicada à residência unifamiliar

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

O aprimoramento de um software de estúdio virtual por meio de técnicas de matting digital e registro de objetos virtuais

A virtual studio system can use technologies as augmented reality and digital matting to decrease production costs at the same time it provides the same resources of a conventional studio. With this, it’s possible for the current studios, with low cost and using conventional devices, to create productions with greater image quality and effects. Some difficulties are recurrent in virtual studio applications that use augmented reality and digital matting. The virtual objects registration in augmented reality techniques suffer from problems caused by optical distortions in the camera, errors in the marker tracking system, lack of calibration on the equipments or on the environment (lighting, for example), or even by delays in the virtual objects display. On the other hand, the digital matting’s main problem is the real-time execution to preview the scene, which must have optimized processing speed at the same time while maintain the best image quality possible. Taking the given context into consideration, this work aims to give continuity to a virtual studio system called ARStudio, by enhancing digital matting, virtual objects registration and introducing a segmentation based on depth map, yet adding better control over functionalities previously implemented

Estudo sobre iluminação e banco de capacitores de uma típica indústria metalúrgica

The use of electricity for obtaining light has been quite an issue currently discussed, either through new technologies that are emerging, the quest for greater efficiency, reduced waste and rational use. This work comprises a lighting design applied to a metallurgical based Brazilian Standard 5413 which mentions levels of luminance for interior and, in the case of this work, for a sandblasting booth. Ways to improve the workplace and luminosity presented before the project and also after its implementation are discussed. Technologies are chosen guided by technical calculations according to the illuminance values they want to reach for the environment studied. All pertinent design features are critically analyzed and discussed, and at the end proposals are presented, relating to each other in a comparative framework, so the best solution is applied in a practical way in the enclosure. Results are also presented concerning the maintenance of a bank of capacitors to correct the power factor for the metals studied company

Proposta de metodologia para aplicação de eficiência energética em uma usina hidrelétrica

Pós-graduação em Engenharia Mecânica - FEG

Desenvolvimento de um conversor estático PWM para o acionamento de LED’S para iluminação publica

This work deals with the development of a switched-mode power supply circuit based on a Buck topology converter with a Boost Rectifier One-Cycle Control with Power Factor Correction developing, thus, a source of direct current for a module of 50 power LEDs that will be used in a lamp for public street lightning. It is presented, at first, some aspects about the most common technologies used in lamps of public street lightning in Brazil and a comparison with the White LED high power, which is the one that presents itself as the most promising among the existing market. Then it is presented the detailed development of the static converter switched PWM, consisting of a Boost rectifier with power factor correction and methodology of control One-Cycle Control associated with a Buck converter controlled by a PI method that operates as a direct current source . At the end of the simulation results of the circuit through the PSIM software are presented to verify the design behavior

Tecnologias virtuais e análise videográfica: o YouTube® como recurso de pesquisa para compreensão sobre a imagem do idoso brasileiro = Virtual technologies and videographic analysis : YouTube® as research resource for understanding about brazilian elderly imagem

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Development of technologies and methods for monitoring the spatial variability of air temperature in greenhouse environment

Climatic factors directly influence growth and productivity of plants inside greenhouses, where temperature can be considered one of the major parameter in this context. Thus, the aim of this research was to develop a low cost device for thermal sensing and data acquisition, and use it in data collection and analysis of spatial variability of temperature inside a greenhouse with tropical climate. The developed equipment for thermal measurements showed a high degree of accuracy and fast responses in measurements, proving its efficiency. The data analysis interpretations were made from the elaborations of variograms and of tridimensional maps generated by a geostatistical software. The processed data analysis presented that a greenhouse without thermal control has spatial variations of air temperature, both in the sampled horizontals layers as in the three analyzed vertical columns, presenting variations of up to 3.6 ºC in certain times.