1,379 research outputs found
Coorbits for projective representations with an application to Bergman spaces
Recently representation theory has been used to provide atomic decompositions
for a large collection of classical Banach spaces. In this paper we extend the
techniques to also include projective representations. As our main application
we obtain atomic decompositions of Bergman spaces on the unit ball through the
holomorphic discrete series for the group of isometries of the ball
SETTING AND HARDENING OF AGRO/CEMENT COMPOSITES
In this study, the use of bagasse fiber (BF) and unbleached bagasse pulp (BP) in a cement matrix, as a raw material, to produce lightweight construction materials is reported. The bagasse was used as partial replacement of cement at different levels: 0% (control cement), 1%, 2% 3%, and 4% by weight. The average size of bagasse fibers was less than 2 mm. Although a reduction in the physical and mechanical strength was observed, the incorporation of either fiber or pulp increased the water of consistency and setting time. A composite containing 4% of bagasse fibers can be used for lightweight concrete. FT-IR spectra showed that the BF or BP adversely affect the rate of calcium silicate hydrate (CSH) formation by decreasing its promotion
Structural Study of Basins Configuration in Mesopotamian Area
Mesopotamian Zone is a foreland basin formed by a collision between Arabian and Iranian plates. A subsurface structural study made for Mesopotamian area based on the information of the oil wells, which were used in the construction of five structural cross-sections. The sections reveal information about the difference in thickness of sedimentary formations in the basin during the geological time of Mesozoic and Cenozoic Era. As well as studied the most important reasons for the formation of surface and subsurface structures, which are attributed to three main reasons: the basement rocks and their longitudinal and transverse faults, tectonic movements that happened to the region as well as the role of salt layers or structures and their rush to the top
Predicting Parkinson disease in the community using a nonmotor risk score
At present, there are no validated methods to identify persons who are at increased risk for Parkinson Disease (PD) from the general population. We investigated the clinical usefulness of a recently proposed non-motor risk score for PD (the PREDICT-PD risk score) in the population-based Rotterdam Study. At baseline (1990), we constructed a weighted risk score based on 10 early nonmotor features and risk factors in 6492 persons free of parkinsonism and dementia. We followed these persons for up to 20 years (median 16.1 years) for the onset of PD until 2011. We studied the association between the PREDICT-PD risk score and incident PD using competing risk regression models with adjustment for age and sex. In addition, we assessed whether the PREDICT-PD risk score improved discrimination (C-statistics) and risk classification (net reclassification improvement) of incident PD beyond age and sex. During follow-up, 110 persons were diagnosed with incident PD. The PREDICT-PD risk score was associated with incident PD (hazard ratio [HR] = 1.30; 95 % confidence interval [1.06; 1.59]) and yielded a small, non-significant improvement in overall discrimination (ΔC-statistic = 0.018[−0.005; 0.041]) and risk classification (net reclassification improvement = 0.172[−0.017; 0.360]) of incident PD. In conclusion, the PREDICT-PD risk score only slightly improves long-term prediction of PD in the community
Study on Portland Cement Pastes Containing Sanitary Ware Ceramic Wastes at Elevated Temperatures
Resistance of Portland cement pastes incorporated 20 wt. % sanitary ware ceramic nano-powder wastes to firing temperatures from 100 up to 600 ℃ was investigated. Results revealed that all physical and mechanical properties were improved and gradually enhanced with firing temperatures, but only up to 400 ℃, and then adversely affected with any further increase of firing temperatures than 400 ℃, i.e. water absorption and total porosity decreased, whereas bulk density was enhanced. Water absorption and total porosity were decreased by 10 and 4 %, respectively, while bulk density was increased by 2.25 %. Furthermore, flexural and compressive strengths were also improved and increased by 1.69 and 1.2 %, respectively. Fourier transform infrared spectra (FT-IR) showed the disappearance of free lime and ettringite on firing. Scanning electron microscopy (SEM) showed that the crystal phase growth of the formed hydration products as a result of both normal hydration and pozzolanic reactions at ambient temperature were developed and modified due to the temperature exposure. The hardened cement pastes can withstand and resist only up to 400 ℃
Cement Pastes Containing Polypropylene Fibers - Part I: Physical, Chemical and Mechanical Properties
The influence of polypropylene fibers (PPF) addition on the physical, chemical, and mechanical properties of Portland cement pastes (OPC) was clearly evaluated. Results showed that as the PPF content increased, the water of consistency (WC) decreased, while the setting times (IST and FST) increased due to the presence of the water reducing mineral admixture (PPF). The Chemically-bound water content (BWn), bulk density (BD), and compressive strength (CS) improved and enhanced up to 0.6 wt. % PPF content, and then decreased onward at all curing times up till 90 days, while the apparent porosity shortened and then enhanced. Above 0.6 wt. % PPF content, all properties were adversely affected. The free lime content (FLn) of the OPC (PP0) increased continuously up till 90 days but decreased with PPF content at all curing ages and with all mixes (PP1-PP7)
Recycling of Concrete Demolition Waste Powder as a Sustainable Material in Portland Cement Pastes Modified with Nano-silica
In recent years, researchers dedicated themselves to explore the possibility of introducing concrete waste powder (CWP) into Portland cement as a sustainable material for Portland cement. To optimize the effect of CWP on cement-based materials, this paper uses nano-silica (NS) to improve the hydration and mechanical properties of cement-based materials with CWP. Results indicated that after adding NS into CWP cement pastes, the setting time of cement pastes was significantly reduced, while the early rate of hydration and hydration heat increased. Besides, the mechanical strengths of the cement pastes increased as CWP replaced at the expense of the cement up till 15 wt. % and, then decreased, while nanosilica (NS) addition can compensate the mechanical strength loss caused by CWP as supplementary cementing materials. The higher ratios of CWP than 15 wt. % increased the pore volume or porosity. In contrast, NS in CWP blended cement significantly decreased the porosity, and increased the proportion of harmless pores. Hence, NS reduced the porosity, which in turn improved and enhanced the bulk density and mechanical strengths. The optimum amount of NS is 2.5 wt. % which resulted in the best results. The heat of hydration of the different cement batches in the two groups adversely affected with the incorporation of CWP, but little improved with NS. The obtained results were confirmed by the ultrasonic pulse velocity (USPV) test, where the cement batch PP15 (Gp I) and PS2.5 (Gp II) achieved the highest conformance. 
Integrated Planner for Autonomous Driving in Urban Environments Including Driving Intention Estimation
名古屋大学Nagoya University博士(情報科学)doctoral thesi
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