We describe an unusual case of a 31-year-old woman who injured the right dominant wrist when she punched an assailant's shoulder. She described a mechanism of direct compression, with the wrist in ...hyperextension, radial deviation and the forearm in pronation. She sustained an oblique transverse fracture of the proximal pole of the scaphoid and a coronal plane fracture of the lunate and the triquetrum. This unusual proximal row transcarpal fracture is in conflict with the Mayfield sequence and was caused by a low velocity injury.
A study is made of the mechanical behavior of a series of binary near-gamma titanium aluminides reinforced with 40-50 volume percent of a discontinuous dispersion of TiB2 particulate. It is found ...that these materials exhibit compressive strengths, short-rod toughness, and elastic modulus values comparable to those of structural ceramics. The actual strength of the composites depends on both the volume fraction of TiB2 and aluminum concentration in the matrix. (AIAA)
Near- gamma ( alpha sub 2 -Ti sub 3 Al+ gamma -TiAl) titanium aluminide intermetallic compounds are presently undergoing extensive development as potential lower-density substitutes for conventional ...high temperature metallic alloys. A significant portion of the effort has focused on the development of acceptable ambient temperature ductility and fracture toughness in an attempt to incorporate these materials into a traditional metallic-based structural material design and fabrication methodology. However, largely unexamined has been the use of intermetallic-based materials in applications historically occupied by, or envisioned for, structural ceramics. This is despite exhibiting certain important commonalities in their macroscopic mechanical behavior which normally serve to ultimately define the utilitive design approach. In this article we describe the mechanical behavior of a series of binary near- gamma titanium aluminides (i.e., Ti-xAl, where xapprox43-48 at.%) reinforced with 40-50 vol.% of a discontinuous dispersion of titanium diboride (TiB sub 2 ) particulate. The composites were synthesized via XD processing, and subsequently consolidated into bulk form using conventional powder metallurgy (P/M) techniques. For composites comprised of such large volume percentages of ceramic, it is suggested and will be shown that it is most appropriate to evaluate and offer a perspective of their evolved mechanical behavior through their comparison to traditional structural ceramics, e.g., silicon carbide (SiC) and alumina (Al sub 2 O sub 3 ).
The current research project proposes advanced statistical and adaptive threshold techniques for video object detection and segmentation. We present new statistical adaptive threshold techniques to ...show the advantages, and how these algorithms overcome the limitations and the technical challenges for object motion detection. The algorithm utilizes statistical quantities such as mean, standard deviation, and variance to define a new adaptive and automatic threshold based on two-frame and three-frame differencing. The proposed algorithms were compared with classic statistical thresholding methods on a testing video for human motion detection, and the experimental results show the effectiveness of the algorithms. Furthermore this research shows an evaluation and comparison among all statistical and adaptive algorithms and proves the benefits of the proposed algorithm.
The galaxy pairwise velocity dispersion (PVD) can provide important tests of non-standard gravity and galaxy formation models. We describe measurements of the PVD of galaxies in the Galaxy and Mass ...Assembly (GAMA) survey as a function of projected separation and galaxy luminosity. Due to the faint magnitude limit (\(r < 19.8\)) and highly-complete spectroscopic sampling of the GAMA survey, we are able to reliably measure the PVD to smaller scales (\(r_\bot = 0.01\) Mpc/h) than previous work. The measured PVD at projected separations \(r_\bot <~ 1\) Mpc/h increases near-monotonically with increasing luminosity from \(\sigma \approx 200\) km/s at \(M_r = -17\) mag to \(\sigma \approx 600\) km/s at \(M_r \approx -22\) mag. Analysis of the Gonzalez-Perez (2014) GALFORM semi-analytic model yields no such trend of PVD with luminosity: the model over-predicts the PVD for faint galaxies. This is most likely a result of the model placing too many low-luminosity galaxies in massive halos.
We describe the case of an 11-year-old boy who presented with a 2-month history of a right-sided painful limp. Roentgenograms and computerized tomography (CT) scanning revealed osteochondritis ...dissecans of the head of the talus. Conservative treatment was successful and roentgenograms 3 years after the onset of the symptoms demonstrated normal density of the talar head. Osteochondritis dissecans of the head of the talus is an extremely rare entity. There are few references in the world literature and no previous description of its CT appearance.
This paper explores the challenges opportunities in developing and deploying 3D TV services. The 3D TV services can be seen as a general case of the multi-view video that has been receiving ...significant attention lately. The keys to a successful 3D TV experience are the availability of content, the ease of use, the quality of experience, and the cost of deployment. Recent technological advances have made possible experimental systems that can be used to evaluate the 3D TV services. We have developed a 3D TV prototype and have currently conducting our first user study to evaluate the quality and experience. These experiences have allowed us to identify challenges and opportunities in developing 3D TV services
The full segmentation of the common carotid artery (CCA) in ultrasound images is important for the evaluation of the intima media thickness (IMT) and for the measurement of the artery stenosis which ...are considered to be the significant markers for the clinical evaluation of the risk of stroke. The current research proposes full-automated segmentation system for the segmentation of the CCA, which is based on an adaptive snake-contour segmentation algorithm. The CCA is segmented by the proposed algorithm into different distinct regions, namely the IMT, intima-media (IL), media-layer (ML), carotid plaque and lumen. The proposed method is automatically processing image normalization, binarization, adaptive hybrid median filter, and morphology prior the application of the snake segmentation algorithm. The mean and standard deviation of the IMT diameter in y-axis of the full-automatically segmented regions for the snakes-based and level-set method are 0.12 mm +/- 0.01 mm and 0.09 mm +/- 0.01 mm respectively in comparison with the ground truth IMT extracted from the manual clinical segmentation. The Wilcoxon rank sum test shows the significant improvements of the proposed method.
We present a direct measurement of the mean halo occupation distribution (HOD) of galaxies taken from the eleventh data release (DR11) of the Sloan Digital Sky Survey-III Baryon Oscillation ...Spectroscopic Survey (BOSS). The HOD of BOSS low-redshift (LOWZ: \(0.2 < z < 0.4\)) and Constant-Mass (CMASS: \(0.43 <z <0.7\)) galaxies is inferred via their association with the dark-matter halos of 174 X-ray-selected galaxy clusters drawn from the XMM Cluster Survey (XCS). Halo masses are determined for each galaxy cluster based on X-ray temperature measurements, and range between \({\rm log_{10}} (M_{180}/M_{\odot}) = 13-15\). Our directly measured HODs are consistent with the HOD-model fits inferred via the galaxy-clustering analyses of Parejko et al. for the BOSS LOWZ sample and White et al. for the BOSS CMASS sample. Under the simplifying assumption that the other parameters that describe the HOD hold the values measured by these authors, we have determined a best-fit alpha-index of 0.91\(\pm\)0.08 and \(1.27^{+0.03}_{-0.04}\) for the CMASS and LOWZ HOD, respectively. These alpha-index values are consistent with those measured by White et al. and Parejko et al. In summary, our study provides independent support for the HOD models assumed during the development of the BOSS mock-galaxy catalogues that have subsequently been used to derive BOSS cosmological constraints.
Multi-view video coding (MVC) is showing a new demand in the video communications, video surveillance systems, video teleconferencing, TV communications, and 3D video games. New algorithms are needed ...to improve video compression and reduce the complexity of multiple views in order to improve the MVC systems. This paper presents the performance evaluation of the hypercube prediction algorithm (HPA) for MVC. The main objective is to minimize the chain view of the dependencies based on the hypercube structure. Using spatio-temporal predictions based on the hypercube structure we show that MVC compression efficiency can be improved while keeping the dependencies low. The proposed HPA for MVC provides increased flexibility in selecting prediction references by reducing the view dependency by a factor of 2. The performance is compared with a linear prediction algorithm (LPA) that uses one spatial and one temporal reference frame. We show that HPA can be used to allow flexible prediction structures that improve the encoding performance while keeping the sufficient the PSNR video quality.
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