2,359 research outputs found
The Theory of Evolution in the Writings of Joseph Ratzinger
In this article I analyse the texts in which Joseph Ratzinger deals with the topic of evolution, particularly in the context of the compatibility between faith in creation and acceptance of the theory of evolution. I have grouped his writings into three periods that reflect the changes in his ideas on this topic. His early writings, until 1979, contain the most elaborate and deepest theological insights, with a defence of the compatibility between faith in creation and the theory of evolution when each one is kept within the boundaries of its own explanatory framework. There is a clear change of attitude at the beginning of the 1980s, when he becomes aware of the attempts by some atheist scientists to portray evolution as a “first philosophy”. This triggers a critical response against some technical aspects of the theory of evolution, a position that was reinforced by his contacts with anti-evolution German intellectuals during this period. The conflict reached its climax in the 1999 lecture at the Sorbonne University and the 2006 meeting of the Schulerkreis in Castel Gandolfo. After 2006 his references to this topic were few, and he seemed to return to the original ideas expressed in his early writings, stressing the intrinsic rationality and inner logic of the cosmos
The effects of solar incidence angle over digital processing of LANDSAT data
A technique to extract the topography modulation component from digital data is described. The enhancement process is based on the fact that the pixel contains two types of information: (1) reflectance variation due to the target; (2) reflectance variation due to the topography. In order to enhance the signal variation due to topography, the technique recommends the extraction from original LANDSAT data of the component resulting from target reflectance. Considering that the role of topographic modulation over the pixel information will vary with solar incidence angle, the results of this technique of digital processing will differ from one season to another, mainly in highly dissected topography. In this context, the effects of solar incidence angle over the topographic modulation technique were evaluated. Two sets of MSS/LANDSAT data, with solar elevation angles varying from 22 to 41 deg were selected to implement the digital processing at the Image-100 System. A secondary watershed (Rio Bocaina) draining into Rio Paraiba do Sul (Sao Paulo State) was selected as a test site. The results showed that the technique used was more appropriate to MSS data acquired under higher Sun elevation angles. Topographic modulation components applied to low Sun elevation angles lessens rather than enhances topography
Recommended from our members
The relationship between suspended sediment concentration and remotely sensed spectral radiance - a review
Information on the concentration of suspended sediments in coastal waters is necessary for the understanding and management of the coastal environment. Traditionally, suspended sediment concentration (SSC) has been measured by time-consuming and costly boat surveys which allow the accurate measurement of SSC for single points in space and time. Remote sensing from airborne and spaceborne sensors has proved to be a useful adjunct to such surveys as it provides an instantaneous and synoptic view of sediments that would otherwise be unavailable. The key to the success of remote sensing in such a role is the strong positive relationship that exists between SSC and remotely sensed spectral radiance (L(x)).
This review provides an introduction to this SSC/L(x) relationship; exploring its physical basis, its robustness under a range of environmental conditions and its utility as a tool for estimation. It is concluded that future research on this relationship should concentrate upon the suppression of environmental influences and the optimum sampling of SSC
Behaviour and evolution of quartzites in detrital accumulations
[Resumen] La presente nota trata de los caracteres y del proceso evolutivo que ofrecen las cuarcitas areniscosas en depósitos detríticos localizados en cuencas-vertientes fluviales y en acumulaciones playeras. La abundancia de este tipo de material en formaciones actuales y antiguas de los valles del Moucide, Xunco y Cabo, desde Cangas de Foz a San Cibrán (Norte de Lugo), ha permitido un estudio estadístico, en términos de actividad morfogenética y textura de los diferentes grupos dimensionales. Ofreciéndose, asimismo, un diagrama-resumen del comportamiento de este material en los diferentes tipos de depósitos.[Abstract] This paper deals with the characteristics and evolution process of quartzites (low Candena quartzites) from detrital deposits of fluvial basics and beach acumulations.The present and past sedimentary formations from Moucide, Xunco and Cobo basics (nord of Lugo, Spain) from Cangas de Foz to San Cibrián are plenty in this. Kind of deposits. That permit us, an statistical analysis-from the point of wiew of texture and morphogenesis, and the study of quartzite behaviour in different types of deposit
Tuned liquid dampers simulation for earthquake response control of buildings
This paper is focused on the study of an earthquake protection system, the Tuned Liquid Damper (TLD), which
can, if adequately designed, reduce earthquake demands on buildings. This positive effect is accomplished taking
into account the oscillation of the free surface of a fluid inside a tank (sloshing). The behaviour of an isolated
Tuned Liquid Damper, subjected to a sinusoidal excitation at its base, with different displacement amplitudes,
was studied by finite element analysis. The efficiency of the TLD in improving the seismic response of an existing building, representative of modern architecture buildings in southern European countries was also evaluated based on linear dynamic analyses
Producing LFT composite parts for large consumption markets from thermoplastic powder-coated towpregs
Thermoplastic matrix composites are receiving increasing interest in last years. This is due to several advantageous properties and speed of processing of these materials as compared to their thermoset counterparts. Among thermoplastic composites, Long Fibre Thermoplastics (LFTs) have seen the fastest growth, mainly due to developments in the automotive sector. LFTs combine the (semi-)structural material properties of long (>1 cm) fibres, with the ease and speed of thermoplastic processing.
This paper reports a study of a novel low-cost LFT technology and resulting composites. A patented powder-coating machine able to produce continuously pre-impregnated materials directly from fibre rovings and polymer powders was used to process glass-fibre reinforced polypropylene (GF/PP) towpregs. Such pre-impregnated materials were then chopped and used to make LFTs in a patented low-cost piston-blender developed by the Centre of Lightweight Structures, TUD-TNO, the Netherlands. The work allowed studying the most relevant towpreg production parameters and establishing the processing window needed to obtain a good quality GF/PP powder coated material. Finally, the processing window that allows producing LFTs of good quality in the piston-blender and the mechanical properties of final stamped GF/PP composite parts were also determined.FCT, Projeto UID/CTM/50025/201
Optimizing the production and processing of fibre reinforced thermoplastic pre-impregnated materials
The aim of this work is to optimize the production of new continuous carbon fibres reinforced polypropylene matrix pre-impregnated materials (towpregs) continuously processed by dry deposition of polypropylene (PP) powder. The processing of the produced towpregs by pultrusion using a prototype equipment was also optimized. The method of Taguchi/DOE (Design of Experiments) was used to achieve this goal allowing improved choices of processing windows. Towpregs were characterized by scanning electron microscopy (SEM), visual analysis and their polymer mass contents were also determined. The final pultruded composite profiles were also submitted to tensile, interlaminar, flexural, calcination and optical microscopy tests.(undefined
Processing conditions and properties of continuous fiber reinforced GF/PP thermoplastic matrix composites manufactured from different pre-impregnated materials
The aim of the present work was to study and compare the processing conditions and final mechanical properties of continuous glass-fiber reinforced polypropylene composites (GF/PP) manufactured by using available thermoplastic preimpregnated materials produced by different methods.To assess the quality of the three different GF/PP pre-impregnated materials, final manufactured composite parts were submitted to mechanical testing and microscopy analysis. The obtained properties were compared between each other and to those theoretical ones that can be predicted by using the Classical amination Theory (CLT).Fundação para a Ciência e a Tecnologia (FCT
- …