64,538 research outputs found
Dynamic nonlinear analyses for the 4-storey infilled R/C frame: study of a retrofitting solution
No full textA research project on assessment and retrofitting of R/C frame structures is currently being developed under the research programme of the ICONS TMR-research network. This paper presents and discusses the preliminary experimental results from a 4-storey bare frame representative of the common practice of 40~50 years ago in most south European countries and devotes special attention to the study of a retrofitting solution based on bracing and rubber dissipaters, which intends to increase stiffness and damping reducing consequently the earthquake deformation demands.O estudo aqui apresentado concentra-se numa solução de reforço de um pórtico utilizando contraventamentos (k-bracing) com perfis de aço em conjunto com elementos elastoméricos de dissipação. Os resultados das análises não lineares da estrutura com e sem alvenaria e com reforço são apresentados e discutidos. Na segunda parte da comunicação apresentam-se os resultados experimentais já disponíveis e discute-se o problema da modelação recorrendo aos resultados experimentais e comparando os resultados obtidos com diferentes tipos de modelos
Improved schemes for inter-frame coding in the H.264/AVC standard
No full textAn efficient algorithm for inter-frame coding in the H.264/AVC standard is extended to provide more significant speedup in computational performance for sequences containing high spatial correlation and motion. The proposed scheme features a more sophisticated search process and robust predictions to achieve better PSNR-rate performance for a large range of compression levels. Extensive simulation results demonstrate speedups of between 41% and 68%, with no noticeable deterioration in picture quality or compression ratio, even for the coding of complex video sequences
Efficient intra- and inter-mode selection algorithms for H.264/AVC
No full textH.264/AVC standard is one of the most popular video formats for the next generation video coding. It provides a better performance in compression capability and visual quality compared to any existing video coding standards. Intra-frame mode selection and inter-frame mode selection are new features introduced in the H.264/ AVC standard. Intra-frame mode selection dramatically reduces spatial redundancy in I-frames, while inter-frame mode selection significantly affects the output quality of P-/B-frames by selecting an optimal block size with motion vector(s) or a mode for each macroblock. Unfortunately, this feature requires a myriad amount of encoding time especially when a brute force full-search method is utilised. In this report, we propose fast mode-selection algorithms tailored for both intra-frames and inter-frames. The proposed fast intra-frame mode algorithm is achieved by reducing the computational complexity of the Lagrangian rate-distortion optimisation evaluation. Two proposed fast inter-frame mode algorithms incorporate several robust and reliable predictive factors, including intrinsic complexity of the macroblock, mode knowledge from the previous frame(s), temporal similarity detection and the detection of different moving features within a macroblock, to effectively reduce the number of search operations. Complete and extensive simulations are provided respectively in these two chapters to demonstrate the performances. Finally, we combine our contributions to form two novel fast mode algorithms for H.264/AVC video coding. The simulations on different classes of test sequences demonstrate a speed up in encoding time of up to 86% compared with the H.264/AVC benchmark. This is achieved without any significant degradation in picture quality and compression ratio
Seismic analyses of a R/C building: study of a retrofitting solution
No full textThe preliminary experimental results from the tests on a 4-storey R/C frame structure are presented and discussed. The full-scale model is representative of the common practice of 40~50 years ago in most south European countries. Special attention is devoted to the study of a retrofitting solution based on bracing and rubber dissipaters, which intends to increase stiffness and damping reducing consequently the earthquake deformation demands
Mode refinement algorithm for H.264 inter frame requantization
No full textThe latest video coding standard H.264 has been recently approved and has already been adopted for numerous applications including HD-DVD and satellite broadcast. To allow interconnectivity between different applications using H.264, transcoding will be a key factor. When requantizing a bitstream the incoming coding decisions are usually kept unchanged to reduce the complexity, but it can have a major impact on the coding efficiency. This paper proposes a novel algorithm for mode refinement of inter prediction in the case of requantization of H.264 bitstreams. The proposed approach gives a comparable quality to a full search for a fraction of its complexity by exploiting the statistical properties of the mode distribution and motion vector refinementThe latest video coding standard H.264 has been recently approved and has already been adopted for numerous applications including HD-DVD and satellite broadcast. To allow interconnectivity between different applications using H.264, transcoding will be a key factor. When requantizing a bitstream the incoming coding decisions are usually kept unchanged to reduce the complexity, but it can have a major impact on the coding efficiency. This paper proposes a novel algorithm for mode refinement of inter prediction in the case of requantization of H.264 bitstreams. The proposed approach gives a comparable quality to a full search for a fraction of its complexity by exploiting the statistical properties of the mode distribution and motion vector refinemen
Letter from C. H. Gensler, Havasupai Agency to Carl Hayden
No full textLetter from C. H. Gensler expressing concern on behalf of the Havasupai Tribe regarding the proposed park boundaries
Citations of the author H C Rajpoot
No full textThe list of the articles, research papers, theses, and book chapters globally citing the author H. C. Rajpoot</p
Letter from Carl Hayden to C. H. Gensler
No full textLetter from Carl Hayden to C. H. Gensler informing him of the proposed Grand Canyon National Park bill
Letter from C. H. Gensler, Havasupai Agency to Carl Hayden
No full textLetter from C. H. Gensler to Carl Hayden asking for a meeting in regards to the Havasupai pasture land in light of the national park bill
The stress distribution in the joints of vehicles chassis frames subject to torsion
No full textThe problem of warping inhibition in the joints, of commercial
vehicle chassis frames is very important for the estimation.
of stress distribution in the joints and the overall torsional
stiffness of frames. The joints being the weakest parts in
the entire frame require that the stress levels should be
estimated when designing a frame for required torsional stiffness.
Plate theory has been applied to-analyse stress distributions
in the joints of a ladder frame-in torsion. The frame consists
of channel section cross members-welded to the web: of the side
members. The degree of cross member warping inhibition in the
welded joints has also been estimated analytically by using
the concept of the strip beam theory. - The analytical values of
stresses have been compared with-photoelastic measurements on
photoelastic models of isolated joints and a complete ladder
frame
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