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21.
Point fingerprint: a new 3-D object representation scheme   总被引:1,自引:0,他引:1  
This paper proposes a new, efficient surface representation method for surface matching. A feature carrier for a surface point, which is a set of two-dimensional (2-D) contours that are the projections of geodesic circles on the tangent plane, is generated. The carrier is named point fingerprint because its pattern is similar to human fingerprints and plays a role in discriminating surface points. Corresponding points on surfaces from different views are found by comparing their fingerprints. The point fingerprint is able to carry curvature, color, and other information which can improve matching accuracy, and the matching process is faster than 2-D image comparison. A novel candidate point selection method based on the fingerprint irregularity is introduced. Point fingerprint is successfully applied to pose estimation of real range data.  相似文献   
22.
Hur JH  Kim KM  Chang M  Lee SR  Lee D  Lee CB  Lee MJ  Kim YB  Kim CJ  Chung UI 《Nanotechnology》2012,23(22):225702
We report a physical model for multilevel switching in oxide-based bipolar resistive memory (ReRAM). To confirm the validity of the model, we conduct experiments with tantalum-oxide-based ReRAM of which multi-resistance levels are obtained by reset voltage modifications. It is also noticeable that, in addition to multilevel switching capability, the ReRAM exhibits extremely different switching timescales, i.e. of the order of 10(-7)?s to 10(0)?s, with regard to reset voltages of only a few volts difference which can be well explained by our model. It is demonstrated that with this simple model, multilevel switching behavior in oxide bipolar ReRAM can be described not only qualitatively but also quantitatively.  相似文献   
23.
Healthcare facilities are often complex and overwhelming for visitors, and wayfinding in healthcare facilities can be challenging. As there is an increasing number of global citizens who travel to seek medical care in another country, it is critical to make wayfinding easy for visitors who are not familiar with the language in a foreign country. Among many wayfinding aids, symbols are helpful for those visitors who have limited ability to understand written language. This study tested universal healthcare symbols in the United States, South Korea, and Turkey to compare the comprehension of symbols cross-country and identify predictors of the correct comprehension. To explore statistically significant relationships between symbol comprehension and countries, Pearson's Chi-square tests, logistic regression, and ANOVA were conducted. The test results showed that ten symbols among 14 tested have significant relationship with countries. Results of this study demonstrate that symbol comprehension can be varied significantly in different countries.  相似文献   
24.
Food Science and Biotechnology - Coronavirus disease 2019 (COVID-19), caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is mainly transmitted through respiratory droplets....  相似文献   
25.
An antimicrobial peptide produced by Bacillus subtilis KU25, KU43, and KU44 was isolated from traditional Korean fermented foods and characterized. It was named as subtilin KU25, KU43, and KU44. Subtilin KU25, KU43, and KU44 were sensitive against α-chymotrypsin, protease XIII, and various proteinase enzymes, respectively. B. subtilis KU43 was selected as the producer with the broadest antimicrobial spectrum. Subtilin KU43 was stable at a pH range of 3 to 9 for 4 h, and withstood exposure to temperatures of 50–90°C for 30 min. The mode of inhibition against Listeria monocytogenes ATCC 15313 involved a bactericidal effect by a reduction in the cell numbers and breakage of the indicator cell membranes. The molecular mass of subtilin KU43 was measured at approximately 3.5 kDa. These results demonstrate the development of novel strains from traditional Korean fermented foods, and illustrate the possibility that some of these strains might generate a natural preservative compound.  相似文献   
26.
Food Science and Biotechnology - The purpose of this study was to evaluate the anti-inflammatory and anti-genotoxic activity of branched-chain amino acids (BCAAs) in lipopolysaccharide (LPS)...  相似文献   
27.
Thermoelastic characteristics of thermal barrier coatings (TBCs) with vertical cracks were analyzed through mathematical approaches to investigate the thermoelastic behaviors of TBCs in a service temperature. TriplexPro?-200 system was applied to prepare the relatively dense TBC using METECO 204NS powder. The microstructure of top coat in the TBC was just controlled to create vertical type cracks by reheating without powder feeding in same equipment and rapid cooling process. A couple of governing partial differential equations were derived based on the thermoelastic theory, and a finite volume model was developed to the governing equations to evaluate the thermoelastic characteristics, such as temperature distribution profile, displacement, and stress, inducing a thermal fatigue. For the specimen with two or more vertical type cracks, smaller displacement appears to longitudinal direction and larger displacement to radial direction as the number of crack increases. In the longitudinal stress distribution profiles to z-direction, the tensile stress at the interface between the bond coat and the substrate converts into the compressive stress when the specimen has vertical cracks more than two, while larger magnitude undulation develops for the specimen with smaller number of crack in the radial stress distribution profiles. The results obtained demonstrate that multiple vertical cracks enhance the thermal durability and extend the lifetime of TBCs.  相似文献   
28.
Journal of Mechanical Science and Technology - The main objective of the present study is to design a bubble collecting section for use in ventilated supercavitation experiments. The large amounts...  相似文献   
29.
Electronics that are capable of destroying themselves, on demand and in a harmless way, might provide the ultimate form of data security. This paper presents materials and device architectures for triggered destruction of conventional microelectronic systems by means of microfluidic chemical etching of the constituent materials, including silicon, silicon dioxide, and metals (e.g., aluminum). Demonstrations in an array of home‐built metal‐oxide‐semiconductor field‐effect transistors that exploit ultrathin sheets of monocrystalline silicon and in radio‐frequency identification devices illustrate the utility of the approaches.  相似文献   
30.
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