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51.
In this paper, we propose a novel robust line orientation code for palmprint verification, whose performance is improved by using three strategies. Firstly, a modified finite Radon transform (MFRAT) is proposed, which can extract the orientation feature of palmprint more accurately and solve the problem of sub-sampling better. Secondly, we construct an enlarged training set to solve the problem of large rotations caused by imperfect preprocessing. Finally, a matching algorithm based on pixel-to-area comparison has been designed, which has better fault tolerant ability. The experimental results of verification on Hong Kong Polytechnic University Palmprint Database show that the proposed approach has higher recognition rate and faster processing speed. 相似文献
52.
In this paper, we propose a novel method to achieve both dense 3D reconstruction of the scene and estimation of the camera intrinsic parameters by using coplanarities and other constraints (e.g., orthogonalities or parallelisms) derived from relations between planes in the scene and reflected curves of line lasers captured by a single camera. In our study, we categorize coplanarities in the scene into two types: implicit coplanarities, which can be observed as reflected curves of line lasers, and explicit coplanarities, which are, for example, observed as walls of a building. By using both types of coplanarities, we can construct simultaneous equations and can solve them up to four degrees of freedom. To upgrade the solution to the Euclidean space and estimate the camera intrinsic parameters, we can use metric constraints such as orthogonalities of the planes. Such metric constraints are given by, for example, observing the corners of rectangular boxes in the scene, or using special laser projecting device composed of two line lasers whose laser planes are configured to be perpendicular. 相似文献
53.
The information resources on the Web are diversified, the amount of which is increasing rapidly. Demands for selecting useful
information from the Internet, managing personal contents, and sharing contents under control have risen. In this study, we
propose the Ubiquitous Personal Study, a framework of personalized virtual study to support accessing, managing, organizing,
sharing and recommending information. In this paper, we focus on discussing the framework, and design and implementation issues
on how to implement it with Web 2.0 mash-up technology and Open Source Software. 相似文献
54.
Ken-ichi Kumagai Kenji Kawano Isao Watanabe Kusuo Nishiyama Kanetada Nagamine 《Journal of Superconductivity》1994,7(1):63-67
Muon spin rotation (
+SR) measurement provides clear evidence of the antiferromagnetic order of Cu moments below 35 K for La2–x
Ba
x
CuO4 and below 15 K for La2–x
Sr
x
CuO4 in the narrow range ofx where the high-T
c
superconductivity (SC) is suppressed remarkably. The results suggest that the change of the electronic state coupled with the lattice instability is relevant to the local suppression of SC and freezing of spin fluctuations of the Cu moment. 相似文献
55.
Craig A. Milroy Seonpil Jang Toshihiko Fujimori Ananth Dodabalapur Arumugam Manthiram 《Small (Weinheim an der Bergstrasse, Germany)》2017,13(11)
Improved thin‐film microbatteries are needed to provide appropriate energy‐storage options to power the multitude of devices that will bring the proposed “Internet of Things” network to fruition (e.g., active radio‐frequency identification tags and microcontrollers for wearable and implantable devices). Although impressive efforts have been made to improve the energy density of 3D microbatteries, they have all used low energy‐density lithium‐ion chemistries, which present a fundamental barrier to miniaturization. In addition, they require complicated microfabrication processes that hinder cost‐competitiveness. Here, inkjet‐printed lithium–sulfur (Li–S) cathodes for integrated nanomanufacturing are reported. Single‐wall carbon nanotubes infused with electronically conductive straight‐chain sulfur (S@SWNT) are adopted as an integrated current‐collector/active‐material composite, and inkjet printing as a top‐down approach to achieve thin‐film shape control over printed electrode dimensions is used. The novel Li–S cathodes may be directly printed on traditional microelectronic semicoductor substrates (e.g., SiO2) or on flexible aluminum foil. Profilometry indicates that these microelectrodes are less than 10 µm thick, while cyclic voltammetry analyses show that the S@SWNT possesses pseudocapacitive characteristics and corroborates a previous study suggesting the S@SWNT discharge via a purely solid‐state mechanism. The printed electrodes produce ≈800 mAh g?1 S initially and ≈700 mAh g?1 after 100 charge/discharge cycles at C/2 rate. 相似文献
56.
Gold nanocages (AuNcgs) are well-studied,hollow,metallic nanostructures that have fascinated researchers in the fields of nanotechnology,materials science,photoelectronics,biotechnology,and medical science for the last decade.However,the time-consuming synthesis of AuNcgs has limited their widespread use in materials science and nano-biotechnology.A novel,ultra-fast,simple,and highly convenient method for the production of AuNcgs using microwave heating is demonstrated herein.This quick method of AuNcg synthesis requires mild laboratory conditions for large-scale production of AuNcgs.The microwave heating technique offers the advantage of precise mechanical control over the temperature and heating power,even for the shortest reaction period (i.e.,seconds).Microwave-synthesized AuNcgs were compared with conventionally synthesized AuNcgs.Structural maneuver studies employing the conventionally produced AuNcgs revealed the formation of screw dislocations and a shift in the lattice plane.Detailed characterization of the microwave-generated AuNcgs was performed using high resolution transmission electron microscopy (HRTEM),scanning electron microscopy (SEM),X-ray powder diffraction (XRD),and spectroscopic techniques. 相似文献
57.
《低温学》2016
A sub Kelvin Active Magnetic Regenerative Refrigerator (AMRR) is being developed at the University of Wisconsin – Madison. This AMRR consists of two circulators, two regenerators, one superleak, one cold heat exchanger, and two warm heat exchangers. The circulators are novel non-moving part pumps that reciprocate a superfluid mixture of 4He–3He in the system. Heat from the mixture is removed within the two regenerators of this tandem system. An accurate model of the regenerators in this AMRR is necessary in order to predict the performance of these components, which in turn helps predicting the overall performance of the AMRR system. This work presents modeling methodology along with results from a 1-D transient numerical model of the regenerators of an AMRR capable of removing 2.5 mW at 850 mK at cyclic steady state. 相似文献
58.
A prediction method for color changes based on the time–temperature superposition principle (TTSP) was developed for acetaminophen solution. Color changes of acetaminophen solution are caused by the degradation of acetaminophen, such as hydrolysis and oxidation. In principle, the TTSP can be applied to only thermal aging. Therefore, the impact of oxidation on the color changes of acetaminophen solution was verified. The results of our experiment suggested that the oxidation products enhanced the color changes in acetaminophen solution. Next, the color changes of acetaminophen solution samples of the same head space volume after accelerated aging at various temperatures were investigated using the Commission Internationale de l’Eclairage (CIE) LAB color space (a*, b*, L* and ΔE*ab), following which the TTSP was adopted to kinetic analysis of the color changes. The apparent activation energies using the time–temperature shift factor of a*, b*, L* and ΔE*ab were calculated as 72.4, 69.2, 72.3 and 70.9 (kJ/mol), respectively, which are similar to the values for acetaminophen hydrolysis reported in the literature. The predicted values of a*, b*, L* and ΔE*ab at 40?°C were obtained by calculation using Arrhenius plots. A comparison between the experimental and predicted values for each color parameter revealed sufficiently high R2 values (>0.98), suggesting the high reliability of the prediction. The kinetic analysis using TTSP was successfully applied to predicting the color changes under the controlled oxygen amount at any temperature and for any length of time. 相似文献
59.
Correlation between Chemical Dopants and Topological Defects in Catalytically Active Nanoporous Graphene
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60.