The compression or tension-controlled failure mode of concrete beams prestressed with unbonded FRP tendons is governed by the relative amount of prestressing tendon to the balanced one. Explicit assessment to determine the balanced reinforcement ratio of a beam with unbonded tendons (q U pfb) is difficult because it requires a priori knowledge of the deformed beam geometry in order to evaluate the unbonded tendon strain. In this study, a theoretical evaluation of q U pfb is presented based on a concept of three equivalent rectangular curvature blocks for simply supported concrete beams internally prestressed with unbonded carbon-fiber-reinforced polymer (CFRP) tendons. The equivalent curvature blocks were iteratively refined to closely simulate beam rotations at the supports, mid-span beam deflection, and member-dependent strain of the unbonded tendon at the ultimate state. The model was verified by comparing its predictions with the test results. Parametric studies were performed to examine the effects of various parameters on q U pfb .

Previous painterly rendering techniques normally use image gradients for deciding stroke orientations. Image gradients are good for expressing object shapes, but difficult to express the flow or movements of objects. In real painting, the use of brush strokes corresponding to the actual movement of objects allows viewers to recognize objects' motion better and thus to have an impression of the dynamic. In this paper, we propose a novel painterly rendering algorithm to express dynamic objects based on their motion information. We first extract motion information (magnitude, direction, standard deviation) of a scene from a set of consecutive image sequences from the same view. Then the motion directions are used for determining stroke orientations in the regions with significant motions, and image gradients determine stroke orientations where little motion is observed. Our algorithm is useful for realistically and dynamically representing moving objects. We have applied our algorithm for rendering landscapes. We could segment a scene into dynamic and static regions, and express the actual movement of dynamic objects using motion based strokes.

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20th World Congress on Ultrasound in Obstetrics and GynecologyPoster abstracts and 3D results were 0.94 for the senior sonographer and 0.93 for the junior sonographer. Conclusions: 3D acquisition is a reproducible and valid technique for first trimester NT assessment. It might resolve limited access to NT measurement and to Down syndrome combined screening. P04.09Why absent flow during the atrial contraction of the ductus venosus Doppler must be considered as a positive marker of Down syndrome? Objectives: To determine whether absent flow during atrial contraction in the Doppler velocimetry of the ductus venosus can improve the predictive capacity of this method in the detection of Down syndrome at 11-14 weeks of gestation. Methods: Ductus venosus Doppler ultrasound blood velocity waveforms were obtained prospectively at 11-14 weeks of gestation in 2495 consecutive singleton pregnancies. In the first group waveforms were classified either as normal in the presence of a positive A-wave, or as abnormal if the A-wave was absent or negative. In the second group, waveforms were classified as abnormal if only A-wave was negative (reverse flow). All cases were screened for chromosomal defects by a combination of maternal age and fetal nuchal translucency thickness. Results: Down syndrome was found in 39 cases. In the first group the flow was abnormal in 30 cases, the overall detection rate, specificity, positive predictive value, negative predictive value and likelihood ratio for trissomy 21 were 76.9%, 99.0%, 54.5%, 99.6% and 75.5 respectively. On basis in the ductus venosus blood flow during atrial contraction as positive marker only A-wave was negative (24 cases) the sensitivity, specificity, the positive and negative predictive values and likelihood ratio were 61.5%, 99.1%, 53.3%, 99.4%, 71.9 respectively. Conclusions: Abnormal ductus venosus blood flow is an useful marker of Down syndrome in the first trimester ultrasound screening. We could improve the predictive for the detection of trisomy 21, and consequently becoming an excellent marker, by considering absent flow during atrial contraction as a positive marker (abnormal). Screening for Down syndrome in Brazil presents comparable results to those in other countries. It is a method of clinical applicability in any part of the world. Supporting information can be found in the online version of this abstract. P04.10 Frontomaxillary facial angle in chromosomally normal P04.11 Fetal nasal bone length nomogram among Filipino population M. L. Asumen-Bullo Ob-Gyn Ultrasound Unit, Manila Central University, Manila, PhilippinesObjectives: To establish reference values for fetal nasal bone length between 11 to 36 weeks AOG among Filipino. Methods: A cross-sectional study was developed in 222 normal pregnant women in their 11 th & 36 th wks AOG. The fetal NBL was measured by transabdominal scan. The 5 th and 95 th percentiles for the NBL measurement was calculated by the formula: mean ± 1.645 SD. The Spearman correlation coefficient with 95% CI was utilized to correlate ...