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151.
In the recent years, the 3D visual research has gained momentum with publications appearing for all aspects of 3D including visual tracking. This paper presents a review of the literature published for 3D visual tracking over the past five years. The work particularly focuses on stochastic filtering techniques such as particle filter and Kalman filter. These two filters are extensively used for tracking due to their ability to consider uncertainties in the estimation. The improvement in computational power of computers and increasing interest in robust tracking algorithms lead to increase in the use of stochastic filters in visual tracking in general and 3D visual tracking in particular. Stochastic filters are used for numerous applications in the literature such as robot navigation, computer games and behavior analysis. Kalman filter is a linear estimator which approximates system's dynamics with Gaussian model while particle filter approximates system's dynamics using weighted samples. In this paper, we investigate the implementation of Kalman and particle filters in the published work and we provide comparison between these techniques qualitatively as well as quantitatively. The quantitative analysis is in terms of computational time and accuracy. The quantitative analysis has been implemented using four parameters of the tracked object which are object position, velocity, size of bounding ellipse and orientation angle. 相似文献
152.
Saeed Hesaraki Touraj Ebadzadeh Shaghayegh Ahmadzadeh-Asl 《Journal of materials science. Materials in medicine》2010,21(7):2141-2149
In this study, bioceramic nanocomposites were synthesized by sintering compacted bodies of hydroxyapatite (HA) mixed with
5 or 15 wt% nanosilicon carbide at 1100 or 1200°C in a reducing atmosphere. Pure hydroxyapatite was also prepared for comparison.
Phase compositions, structural and physical properties of the composites were studied using appropriate techniques. Some in
vitro biological properties of the composites were also investigated by using newrat calvaria osteoblastic cells. X-ray diffraction
analysis indicated that tricalcium phosphate (TCP) comprising negligible α-TCP and considerable β-TCP were formed in composites
during sintering meanwhile hydroxyapatite and silicon carbide (SiC) were also existed in the composition. Based on the results,
that composite made of 5 wt% nanosilicon carbide exhibited higher bending strength, fracture toughness and bulk density than
pure HA and composite with 15 wt% silicon carbide. The scanning electron microscopy coupled with energy dispersive X-ray analysis
revealed that the addition of nanosilicon carbide suppressed the grain growth and yielded a feature of island-type clusters
consisting of blistered calcium phosphate (HA and TCP) and SiC grains. Also, in this study, better proliferation rate and
alkaline phosphatase activity were observed for the osteoblastic cells seeded on top of the composites compared to pure HA.
Overall, the results indicated that the composite of 95 wt% hydroxyapatite and 5 wt% SiC exhibited better mechanical and biological
properties than pure HA and further addition of SiC failed strength and toughness. 相似文献
153.
Abbas Saeed Hakeem Jekabs Grins Saeid Esmaeilzadeh 《Journal of the European Ceramic Society》2007,27(16):4783-4787
Vickers hardness and refractive index have been determined for a series of La-Si-O-N oxy-nitride glasses containing 30–62 e/o of La and 9–68 e/o of N. The hardness varies between 7.7 and 11.5 GPa at a load of 1 kg and is dependent of the N content, while the La content does not influence it significantly. The increase of the hardness with N content is, contrary to reported findings for other oxy-nitride glasses, found not to be linear over the whole compositional range. The refractive index varies between 1.8 and 2.3 and increases non-linearly with increasing N content. The compositional variations of hardness and refractive index are compared with previously published results. 相似文献
154.
Role of quaternary ammonium salts in improving the fastness properties of anionic dyes on cellulose fibres 总被引:1,自引:0,他引:1
The object of this study was to review the developments taking place during 1990–2005 regarding the use of quaternary ammonium salts as dye fixing agents for improving the fastness properties of anionic dyes on cellulose fibres. As far as fastness properties are concerned, this review is restricted only to fastness to light, washing and water treatments. 相似文献
155.
Kesavan Sunil K. Reddy Narender P. Yazdani-Ardakani Saeed 《IEEE transactions on bio-medical engineering》1986,(9):898-900
Water irrigation devices (WID's) are widely used in homes and dental clinics across the country for oral hygiene. There have been several reported cases of tissue damage with the use of these devices. In the present investigation, two commercially available oral water irrigation devices were evaluated using engineering techniques. The impact thrusts delivered by these devices were measured at different control settings. Both of the tested commercial oral water irrigation devices were found to exert abnormally high thrust which could cause serious damage to the sulcular epithelium and the underlying tissues. These pressures are far in excess of the pressure intensity necessary to perform the cleaning action. Moreover, the existing designs using reciprocating pumps are unsafe and are potentially dangerous, particularly with small diameter tips. 相似文献
156.
Different nano-silicas were incorporated in an automotive OEM clear-coat based on acrylic-melamine chemistry. The morphological characteristics of the heat-cured films were investigated using scanning electron microscopy. It was found that there is a close relationship between the interfacial interactions of binder-silica nano-particles and mechanical and optical properties of the baked films. 相似文献
157.
158.
The performance of an upflow packed-bed biofilm reactor has been analyzed under multisubstrate limitation by considering simultaneous carbon oxidation and nitrification reactions. The fasting shock load of inlet methanol concentration has a much more pronounced effect on the response of the system compared to that of inlet NH4+ -nitrogen concentration. The exit concentration of NH4+ -nitrogen drops very close to zero, thereby showing essentially complete nitrification during methanol fasting condition. Further, the concentration profiles of oxygen within the biofilm show significant variation during methanol fasting and nonfasting conditions whereas during NH4+ -nitrogen fasting conditions the oxygen concentration profile in the biofilm remains essentially unaffected. 相似文献
159.
Amal Badshah Khattak Aurang Zeb Maazuulah Khan Nizakat Bibi Ihsanullah Mohammad Saeed Khattak 《Food chemistry》2007,103(1):115-120
Effects of germination time and illuminations on sprout yield, biosynthesis of ascorbic acid, cooking ability and moisture accumulation in chickpeas were significant (p ? 0.01). Green light had the highest promoting effect on the ascorbic acid level (40.59 mg/100 g) as compared to other illuminations but significantly reduced the sprout yield (188.6 g) as compared to dark, fluorescence and γ-rays illuminations with significantly high sprout yield (196 g) and imbibing moisture (51%). Cooking time was reduced by 43% due to γ-rays in un-soaked seed. Cooking time increased in all treated chickpea samples after 24 h germination and thereafter decreased significantly. Red light significantly increased the cooking time (68.44 min) followed by fluorescent (64.5 min), yellow (61.8 min) and green light (60.9 min). The results indicated that germination of chickpea under green light was an effective process in enhancing ascorbic acid content while dark, fluorescence and γ-rays were effective in promoting sprout growth and to some extent biosynthesis of ascorbic acid. 相似文献
160.
A procedure is presented for the proper design of systems comprising photovoltaic solar generators directly supplying DC motors. The method is based on maximizing the total annual gross mechanical energy delivered to a mechanical load with a given torque-speed characteristic. The seasonal variations of both the isolation level and the ambient temperature are taken into account. The proposed technique is applied to two practical case studies, and the resulting optimal design parameters are compared with those available in the literature. A comparison is also made between the optimal separately excited and series motor design alternatives regarding the annual gross mechanical output energy 相似文献