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排序方式: 共有7349条查询结果,搜索用时 31 毫秒
51.
Marco Lucamarini Alessandro Ceré Giovanni Di Giuseppe Stefano Mancini David Vitali Paolo Tombesi 《Open Systems & Information Dynamics》2007,14(2):169-178
The security of a deterministic quantum scheme for communication, namely the LM05 [1], is studied in presence of a lossy channel
under the assumption of imperfect generation and detection of single photons. It is shown that the scheme allows for a rate
of distillable secure bits higher than that pertaining to BB84 [2]. We report on a first implementation of LM05 with weak
pulses. 相似文献
52.
Marco A. Arteaga Author Vitae 《Automatica》2003,39(1):67-73
Most adaptive control schemes for rigid robots assume velocities measurements to be available. Although it is possible to measure velocities by using tachometers, this increases costs and the signals delivered may be contaminated with noise. Since the use of encoders allows to read joint position pretty accurately, it is desirable to estimate joint velocities through an observer. This paper presents an adaptive scheme designed in conjunction with a linear observer. Boundedness of the estimated parameters and uniform ultimate boundedness for the tracking and observation errors are guaranteed. Experimental results are included to support the developed theory. 相似文献
53.
The counter current heat exchanger theory with periodic inlet temperatures has been applied to analyze the thermal performance of a water heating system. The theoretical results obtained are in agreement with the experimental data reported in the literature. 相似文献
54.
Alok Kumar Rastogi A. K. Tiwari 《Journal of Infrared, Millimeter and Terahertz Waves》1993,14(9):1825-1845
A shielded suspended dielectric guide is a dielectric rectangular slab enclosed by regular metallic side walls from all the sides. This type of structure is used in dual mode phase shifter where the size of the normal rectangular wave guide is reduced at the ends, where a dielectric material is embeded in ferrite core. Hence impedance variation of a phase shifter at its transition may be easily calculated using shielded suspended dielectric guide which is a prime parameter for optimum efficiency of wave launching. 相似文献
55.
56.
Maheshwari Rashmi Kumar Naveen Shadi Monal Tiwari Shailesh 《The Journal of supercomputing》2021,77(8):8653-8673
The Journal of Supercomputing - Data availability ensures efficient data accessibility by the readers anytime and from anywhere. It can be addressed by creating multiple copies of each data file... 相似文献
57.
Michel P. Tcheou André L.L. Miranda Lisandro Lovisolo Eduardo A.B. da Silva Marco A.M. Rodrigues Paulo S.R. Diniz 《Digital Signal Processing》2012,22(2):288-297
In this paper, we verify how far electric disturbance signals can be compressed without compromising the analysis of encoded fault records. A recently proposed compression algorithm, referred to as Damped Sinusoidal Matching Pursuit (DSMP) has the remarkable feature of obtaining both compact and physically interpretable representations. However, for fault analysis applications, one is primarily interested in how accurate can be the analysis performed on compressed signals, instead of evaluating mean-squared error figures. Unlike previous works in digital fault records compression, the performance of the DSMP compression method is evaluated using a protocol based on fault analysis procedures commonly performed by expert engineers. This protocol is applied for comparing the results obtained in the analysis of both uncompressed records and their compressed versions at different compression ratios. The results show that the DSMP is a reliable compression system since it achieves high compression ratios (6.4:1) without causing fault analysis misinterpretation. 相似文献
58.
Dellepiane M Marroquim R Callieri M Cignoni P Scopigno R 《IEEE transactions on visualization and computer graphics》2012,18(3):463-474
The projection of a photographic data set on a 3D model is a robust and widely applicable way to acquire appearance information of an object. The first step of this procedure is the alignment of the images on the 3D model. While any reconstruction pipeline aims at avoiding misregistration by improving camera calibrations and geometry, in practice a perfect alignment cannot always be reached. Depending on the way multiple camera images are fused on the object surface, remaining misregistrations show up either as ghosting or as discontinuities at transitions from one camera view to another. In this paper we propose a method, based on the computation of Optical Flow between overlapping images, to correct the local misalignment by determining the necessary displacement. The goal is to correct the symptoms of misregistration, instead of searching for a globally consistent mapping, which might not exist. The method scales up well with the size of the data set (both photographic and geometric) and is quite independent of the characteristics of the 3D model (topology cleanliness, parametrization, density). The method is robust and can handle real world cases that have different characteristics: low level geometric details and images that lack enough features for global optimization or manual methods. It can be applied to different mapping strategies, such as texture or per-vertex attribute encoding. 相似文献
59.
60.
Hugo Feitosa de Figueirêdo Yuri Almeida Lacerda Anselmo Cardoso de Paiva Marco Antonio Casanova Cláudio de Souza Baptista 《Multimedia Tools and Applications》2012,59(1):279-305
The recent popularity of digital cameras has posed a new problem: how to efficiently store and retrieve the very large number
of digital photos captured and chaotically stored in multiple locations without any annotation. This paper proposes an infrastructure,
called PhotoGeo, which aims at helping users with the people photo annotation, event photo annotation, storage and retrieval
of personal digital photos. To achieve the desired objective, PhotoGeo uses new algorithms that make it possible to annotate
photos with the key metadata to facilitate their retrieval, such as: the people who were shown in the photo (who); where it was captured (where); the date and time of capture (when); and the event that was captured. The paper concludes with a detailed evaluation of these algorithms. 相似文献