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91.
Lei Zhang Sung-In Choi Soon-Yong Park 《International Journal of Control, Automation and Systems》2013,11(5):1001-1008
Registration of range scans is commonly required in many localization and mapping algorithms. In this paper, we introduce a novel approach called Polar-Cartesian Hybrid Transforms for pair-wise registration of range scans. The proposed algorithm iteratively establishes correspondences by searching the points with closest polar angles in the polar coordinate frame. An angular look-up table is constructed based on the properties of the laser range finder to accelerate the searching procedure. In order to speed up the convergence, we compute the difference of polar range of every matched point pair to select the most contributing correspondences. After the correspondences are determined, the transformation is computed in Cartesian coordinate frame using a point-to-line metric. Combining the advantages of the polar and Cartesian coordinate frames, both robustness and efficiency are greatly improved compared with an up-to-date ICP algorithm. 相似文献
92.
93.
J. Jiang Fanghua Mei W. J. Meng G. B. Sinclair Sunggook Park 《Microsystem Technologies》2008,14(6):815-819
For direct imprinting of metals, hard materials such as diamond and SiC have been used to construct mold inserts in preference
to Si, despite the ease in fabricating Si-based micro-/nano- scale structures. In this communication, we demonstrate that
micron scale Al structures can be replicated with good fidelity at room temperature by compression molding with Si inserts
without incurring insert damage. We further report on results of a finite element analysis of the mechanics of the molding
process. The finite element results provide some understanding of the observed lack of damage to the Si inserts. 相似文献
94.
Wen-Ke Wang Hui Zhang Hyungjun Park Jun-Hai Yong Jean-Claude Paul Jia-Guang Sun 《Computer aided design》2008,40(10-11):999-1008
A new algorithm for reducing control points in lofted surface interpolation to rows of data points is presented in this paper. The key step of surface lofting is to obtain a set of compatible B-spline curves interpolating each row. Given a set of points and their parameterization, a necessary and sufficient condition is proposed to determine the existence of interpolating B-spline curves defined on a given knot vector. Based on this condition, we first properly construct a common knot vector that guarantees the existence of interpolating B-spline curves to each row of points. Then we calculate a set of interpolating B-spline curves defined on the common knot vector by energy minimization. Using this method, fewer control points are employed while maintaining a visually pleasing shape of the lofted surface. Several experimental results demonstrate the usability and quality of the proposed method. 相似文献
95.
A ring cavity system consisting of two hybrid Michelson interferometers coupled together with feedback is constructed. This system shows spatial bifurcation and can be utilized as an all-optical flip-flop device. We demonstrate experimentally a flip-flop operation by use of only a positive pulse in this system. 相似文献
96.
97.
Translucent scattering phantoms hidden inside a 5.5-cm-thick Intralipid solution were imaged as a function of phantom scattering coefficients by the use of a picosecond time- and space-gated Kerr-Fourier imaging system. A 2-mm-thick translucent phantom with a 0.1% concentration (scattering coefficient) difference from the 55-mm-thick surrounding scattering host can be distinguished at a signal level of ~10(-10) of the incidence illumination intensity. 相似文献
98.
99.
100.
Seungae Lee Jahyun Koo Seung-Kyun Kang Gayoung Park Yung Jong Lee Yu-Yu Chen Seon Ah Lim Kyung-Mi Lee John A. Rogers 《Materials Today》2018,21(3):207-215
Biologically and environmentally resorbable electronic devices support application possibilities that cannot be addressed with conventional technologies. This paper presents highly conductive, water-soluble composites that can be printed to form contacts, interconnects, antennas, and other important features that are essential to nearly all systems of this type. An optimized material formulation involves in situ polymerization to yield a polyanhydride containing a dispersion of molybdenum microparticles at appropriate concentrations. Comparisons of essential physical and electrical properties of these materials to those of composites formed with other polymers and other metal microparticles reveal the relevant considerations. Various functional demonstrations of screen-printed test structures and devices illustrate the suitability of these conductive inks for use in water-soluble electronic devices. A key advantage of the material introduced here compared to alternatives is its ability to maintain conductance over significant periods of time while immersed in relevant aqueous solutions. Studies involving live animal models establish the biocompatibility. 相似文献