2,776 research outputs found
Fixation for coarsening dynamics in 2D slabs
For the zero temperature limit of Ising Glauber Dynamics on 2D slabs the
existence or nonexistence of vertices that do not fixate is determined as a
function of slab thickness.Comment: 16 pages, 9 figure
Target Localization Accuracy Gain in MIMO Radar Based Systems
This paper presents an analysis of target localization accuracy, attainable
by the use of MIMO (Multiple-Input Multiple-Output) radar systems, configured
with multiple transmit and receive sensors, widely distributed over a given
area. The Cramer-Rao lower bound (CRLB) for target localization accuracy is
developed for both coherent and non-coherent processing. Coherent processing
requires a common phase reference for all transmit and receive sensors. The
CRLB is shown to be inversely proportional to the signal effective bandwidth in
the non-coherent case, but is approximately inversely proportional to the
carrier frequency in the coherent case. We further prove that optimization over
the sensors' positions lowers the CRLB by a factor equal to the product of the
number of transmitting and receiving sensors. The best linear unbiased
estimator (BLUE) is derived for the MIMO target localization problem. The
BLUE's utility is in providing a closed form localization estimate that
facilitates the analysis of the relations between sensors locations, target
location, and localization accuracy. Geometric dilution of precision (GDOP)
contours are used to map the relative performance accuracy for a given layout
of radars over a given geographic area.Comment: 36 pages, 5 figures, submitted to IEEE Transaction on Information
Theor
Simulation of an Asymmetric Transvers Electric TE Metamaterial Absorber
This paper introduces the principle method and simulation of an asymmetric TE (transverse electric) mode absorption in a lossy artificial metamaterial (LHM (left-handed material)). LHM is sandwiched between a lossy substrate and covered by a lossless dielectric cladding. The asymmetry solutions of the eigenvalue equation describe lossy-guided modes with complex-valued propagation constants. The dispersion relations, normalized field and the longitudinal attenuation were numerically solved for a given set of parameters: frequency range; film’s thicknesses; and TE mode order. We found that high order modes, which are guided in thinner films, generally have more loss of power than low-order modes since the mode attenuation along z-axis z α increases to negative values as the mode’s number increases, and the film thickness decreases. Moreover, for LHM, at incident wavelength= 1.9 m μ, refractive index= 2i 3.74+-and at thickness m μ 3.0=, the modes of order (4, 5, 6) attain high positive attenuation which means these modes have larger absorption lengths and they are better absorber than the others. This LHM is appropriate for solar cell applications. For arbitrary LHM, at frequency band of wavelengt (600, 700 to 900 nm), the best absorption is attained at longer wavelengths and for lower order modes at wider films. The obtained results could be useful for the design of future light absorbers
Juvenile \u3ci\u3eMiranda\u3c/i\u3e Waivers and Wrongful Convictions (Winner of American Constitution Society\u27s National Student Writing Competition)
Aktivitas Protease Dan Amilase Pada Ikan Sidat Anguilla Bicolor Mcclelland)
This study was experimental, conducted using a Completely Randomized Design (CRD) with 3 x 2 factorial design, and four replicates have been carried out to evaluate the protease and amylase activities of Anguilla bicolor McClelland. A total of 71 individuals divided into three weight groups were used in this study. The first group with an average weight of 41.25 ± 0.898 g consisted of 51 eels, the second with an average weight of 319.8 ± 4.666 g composed of 14 eels, and the third with a mean weight of 569.5 ± 9.150 g consisted of 6 eels. The results showed the protease activity differed significantly based on eel size and intestinal segment (P ˂ 0.05). This research recorded the highest protease activity was in eels within the smallest weight group (41.25 ± 0.898 g). This study also revealed the protease activity in the anterior intestine was higher than the posterior in all size of eels. The amylase activity did not differ significantly (P>0.05) by eel size and intestinal segment. This study concluded the protein digestion capacity of smaller eels was higher than larger eels, and the protein digestion capacity was greater in the anterior intestine than the posterior intestine. The carbohydrate absorption capacity in eel was not affected by the variety of fish size which indicates no change in the feed category
On The CW Complex of the Complement of A Hypersolvable Graphic Arrangement
This paper interested in studying a CW complex for the complement of a hypersolvable graphic arrangement that related to a hypersolvable graph , by comparing it with the minimal CW complex for the complement of Jambu's-Papadima's deformed supersolvable arrangement . Motivated by our aim, a dimension of the first non-vanishing higher homotopy group for was calculated and a fashion of the cohomological ring of the complement was considered, just by using the hypersolvable partition analogue on . Moreover, an algorithm to deform any hypersolvable graph into a supersolvable graph was stated. Key-words: connected simple graph, graphic arrangement, hypersolvable (supersolvable) graph, Orlik-Solomon algebra, no broken circuit module, CW complex...
Cephalometric studies of the mandible, its masticatory muscles and vasculature of growing Göttingen Minipigs — A comparative anatomical study to refine experimental mandibular surgery
Over many decades, the Göttingen Minipig has been used as a large animal model in experimental surgical research of the mandible. Recently several authors have raised concerns over the use of the Göttingen Minipig in this research area, observing problems with post-operative wound healing and loosening implants. To reduce these complications during and after surgery and to improve animal welfare in mandibular surgery research, the present study elucidated how comparable the mandible of minipigs is to that of humans and whether these complications could be caused by specific anatomical characteristics of the minipigs’ mandible, its masticatory muscles and associated vasculature. Twenty-two mandibular cephalometric parameters were measured on CT scans of Göttingen Minipigs aged between 12 and 21 months. Ultimately, we compared this data with human data reported in the scientific literature. In addition, image segmentation was used to determine the masticatory muscle morphology and the configuration of the mandibular blood vessels. Compared to data of humans, significant differences in the mandibular anatomy of minipigs were found. Of the 22 parameters measured only four were found to be highly comparable, whilst the others were not. The 3D examinations of the minipigs vasculature showed a very prominent deep facial vein directly medial to the mandibular ramus and potentially interfering with the sectional plane of mandibular distraction osteogenesis. Damage to this vessel could result in inaccessible bleeding. The findings of this study suggest that Göttingen Minipigs are not ideal animal models for experimental mandibular surgery research. Nevertheless if these minipigs are used the authors recommend that radiographic techniques, such as computed tomography, be used in the specific planning procedures for the mandibular surgical experiments. In addition, it is advisable to choose suitable age groups and customize implants based on the mandibular dimensions reported in this study
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