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821.
Chang-Yu Lu Myung-Cheol Roh Seung-Yeon Kang Seong-Whan Lee 《Pattern Analysis & Applications》2012,15(2):175-187
The amount of user created contents has been increasing rapidly and is associated with a serious copyright problem. Automatic logo detection and recognition in videos is a natural and efficient way of overcoming the copyright problem. However, logos have varying characteristics, which make logo detection and recognition very difficult. Moreover, logo transitions between two different logos exist in one video comprising several video contents. This disrupts the automatic logo detection and recognition. Therefore, in order to improve logo detection, it is necessary to take into account the logo transitions explicitly. This paper proposes an accurate logo transition detection method for recognizing logos in digital video contents. The proposed method accurately segments a video according to logo and efficiently recognizes various types of logos. The experimental results demonstrate the effectiveness of the proposed method for logo detection and video segmentation according to logo. 相似文献
822.
Yuhao Yang Enzhou Liu Hongzhe Dai Limin Kang Huitong Wu Jun Fan Xiaoyun Hu Hanchen Liu 《International Journal of Hydrogen Energy》2014
TiO2-graphene (P25-GR, PG) nanocomposite was fabricated with P25 and graphite oxide through a hydrothermal method, and then Ag nanoparticles (Ag NPs) was assembled in P25-GR (Ag-P25-GR, APG) under microwave-assisted chemical reduction. The prepared samples were characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscope (SEM), transmission electron microscopy (TEM), photoluminescence spectrum (PL), UV–vis absorption spectrum (UV–vis) and Raman spectrum, respectively. The results showed that Ag NPs were well dispersed on the surface of PG with metallic state. The ternary Ag-P25-GR (APG) nanocomposites possessed the extended light absorption range and more efficient charge separation properties compared to binary P25-GR (PG). Methylene blue photodegradation experiment proved that surface plasmon resonance (SPR) phenomenon had an effect on photoreaction efficiency. The corresponding hydrogen evolution rate of APG prepared with 0.002 M AgNO3 solution was 7.6 times than pure P25 and 2.7 times than PG in the test condition. The improved photocatalytic performance can be attributed to the presence of GR and SPR effect, leading to the longer lifetime of photo-generated electron–hole pairs and faster interfacial charge transfer rate. This work indicates that the photoactivity of ternary GR-based nanocomposites is superior to the binary one. We expected our work could give a new train of thought on exploration of GR-based nanocomposites. 相似文献
823.
Various expert system development approaches were proposed but most of them cannot deal with two problems: the difficulty of analysis and maintenance. Rather than to spend time waiting any longer, it is better to find an alternative solution from other research fields. In computer software development area, researchers have been suffering from the difficulty of maintenance and analysis, just as the researchers in the expert system development field. To solve this issue, researchers in the software used both agile software development and business rules approach: agile software development is for overcoming the the difficulty of analysis, and business rules approach is for reducing issues in the maintenance. There is a big opportunity that those two approaches can also be solve the two issues in the expert system development field. The paper describes requirements of the approach based on agile software development and the business rules approach. As a result, we consider and specify why the Multiple Classification Ripple Down Rules is the novel approach for the expert system development. 相似文献
824.
Jinsun Yoon Hong-kyu Song Sungjin Park Jongok Won Yong Soo Kang 《Polymer Bulletin》2014,71(8):2053-2065
We have investigated the effects of localized surface plasmons (LSPs) on the performance of quasi-solid-state dye-sensitized solar cells (DSSCs). Ag and Au nanoparticles (NPs) were prepared by photoreduction in the presence of generation 5 polyester hydroxyl acetylene bis(hydroxymethyl)propanoic acid dendrons (Dendron) as a stabilizer. The plasmon-enhanced DSSCs were achieved by incorporating metal@Dendron NPs into TiO2 photoanodes. The presence of dendrons prevents the photoelectrons from recombining on the surface of TiO2 semiconductor and improves the stability of metal NPs. With the addition of Ag@Dendron NPs, the photocurrent and the power conversion efficiency of quasi-solid-state DSSCs increased due to the LSP effect of metal NPs and the barrier effect of dendron, which were confirmed by the increased incident photon-to-photocurrent efficiency and by electrochemical impedance spectroscopy analysis. 相似文献
825.
Park Ji-Woo Ku Tae-Wan Kim Jeong Kim Kwang-Ho Kang Beom-Soo 《Journal of Mechanical Science and Technology》2016,30(5):2203-2210
Journal of Mechanical Science and Technology - Flexible forming technology such as Multi-point dieless forming (MDF) has benefits for the sheet metal field because it can implement a variety of... 相似文献
826.
随着我国交通事业的发展,其对桥梁的结构和性能也提出了更高的要求。本文主要分析了大跨高墩连续刚构桥不对称悬臂段施工现状和主要施工技术要点,并成功将其应用于实际,以期为同类桥型的施工提供借鉴。 相似文献
827.
828.
Roll-to-roll (R2R) slot-die coating systems are mostly devoted to the mass manufacture of printed electronics. This study examined the correlation among the operating conditions, thickness, and width of the patterned strip fabricated by the R2R slot-die system. A full factorial experiment was conducted to screen for effective parameters. The velocity of a moving substrate was found to be the most dominant parameter affecting the thickness and width of the patterned strips. The flow ratio of the supply to the slot-die, and gap between substrate and slot-die did not affect the width of the strip, but affected the thickness; therefore, the flow ratio and gap can be employed for the independent patterning of thickness against width. In addition, it was proposed to determine the R2R process conditions, such as gap, velocity, and flow ratio for the desired thickness and width of the patterned strips. 相似文献
829.
Dimensional variation in assembly processes is one of the most important issues that affect quality. Although robust design and statistical process quality control help to reduce this problem, they cannot be used for instant variation reduction during assembly operations, especially during process ramp-up. This paper introduces a complete methodology for dimensional-related error compensation in compliant sheet metal assembly processes. The proposed methodology is divided into two steps: (1) an off-line error control-learning module using virtual assembly models to determine necessary adjustments; and (2) an in-line control implementation using a feed-forward control strategy based on the learned adjustments. The off-line learning step focuses on determining control actions or corrections to compensate for the negative effects incoming part errors have on Key Product Characteristics. Specifically, it utilizes a newly developed iterative sampling method based on Kriging fitting to efficiently determine optimal control actions. The in-line feed-forward control identifies appropriate part-by-part adjustments using these learned control actions and incoming assembly component measurements. In this paper, two case studies are presented. First, a mathematical case study presents an empirical proof for the feasibility of the Iterative Sampling and Fitting Algorithm. Second, a simulation-based case study illustrates the effectiveness of the proposed methodology to improve dimensional quality in assembly operations for compliant sheet metal parts. 相似文献
830.
Malrey Lee Eun-Kwan Kang 《Soft Computing - A Fusion of Foundations, Methodologies and Applications》2012,16(3):419-425
Path design uses information about termite reproduction and the termite environment necessary for tunneling. Features are
extracted by analyzing relevance of this information, and the fitness and relevance of these features are evaluated. The proposed
method is demonstrated and is capable of finding various optimal termite tunneling paths. 相似文献