排序方式: 共有36条查询结果,搜索用时 15 毫秒
1.
2.
Fan Jianping Zhu Xingquan Najarian Kayvan Wu Lide 《Multimedia Tools and Applications》2003,21(1):75-96
In order to support content-based video database access over the Internet Protocol (IP), achieving the following objectives are important: (i) video query by a representative object (key object) or some statistical characterization of the target contents, (ii) bandwidth-efficient browsing over IP, and (iii) scalable and user-centric video transmission over a heterogeneous and variable-bandwidth network. We present a video object extraction and scalable coding system designed to meet the above objectives. In our system, key objects of meaning to video database users are generated via a human-computer-interaction procedure, and are tracked across frames. Given a key object, an algorithm classifies a subset of its VOPs as key VOPs. This subset forms the basis of a highly bandwidth-efficient base layer for supporting activities such as browsing and refining queries. Over the base layer, a number of enhancement layers can be defined to progressively increase the spatial and temporal resolutions of retrieved video. It is expected that heterogeneous users can subscribe to different numbers of the enhancement layers according to their own conditions, such as access authorization, available connection bandwidth, and quality preference. 相似文献
3.
Scientometrics - Citation-based indicators are often used to help evaluate the impact of published medical studies, even though the research has the ultimate goal of improving human wellbeing. One... 相似文献
4.
Kayvan Aghabayk Nafiseh Forouzideh William Young 《Computer-Aided Civil and Infrastructure Engineering》2013,28(8):581-593
Because car‐following (CF) models are fundamental to replicating traffic flow they have received considerable attention over the last 50 years. They are in a continuous state of improvement due to their significant role in traffic microsimulations, intelligent transportation systems, and safety engineering models. This article uses the local linear model tree (LOLIMOT) approach to model driver's CF behavior to incorporate human perceptual imperfections into a CF model. This model defines some localities in the input space. These localities are fuzzy and have overlaps with each other. Specific models for each of the localities are then defined and combined in a fuzzy manner to predict the final output. The model was developed using real world dynamic data sets. Three different data sets were used for training, testing, and validating the model. The performance of the model was compared to a number of existing CF models. The results showed very close agreement between the real data and the LOLIMOT outputs. 相似文献
5.
Network virtualization: state of the art and research challenges [Topics in Network and Service Management] 总被引:1,自引:0,他引:1
Recently network virtualization has been pushed forward by its proponents as a long-term solution to the gradual ossification problem faced by the existing Internet and proposed to be an integral part of the next-generation networking paradigm. By allowing multiple heterogeneous network architectures to cohabit on a shared physical substrate, network virtualization provides flexibility, promotes diversity, and promises security and increased manageability. However, many technical issues stand in the way of its successful realization. This article investigates the past and the state of the art in network virtualization along with the future challenges that must be addressed to realize a viable network virtualization environment. 相似文献
6.
The PAC learning theory creates a framework to assess the learning properties of static models. This theory has been extended
to include learning of modeling tasks with m-dependent data given that the data are distributed according to a uniform distribution.
The extended theory can be applied for learning of nonlinear FIR models with the restriction that the data are unformly distributed.
In this paper, The PAC learning scheme is extended to deal with any FIR model regardless of the distribution of the data.
This fixed-distribution m-dependent extension of the PAC learning theory is then applied to the learning of FIR three-layer
feedforward sigmoid neural networks. 相似文献
7.
Etemad Elham Samavi Shadrokh Reza Soroushmehr S. M. Karimi Nader Etemad Mohammad Shirani Shahram Najarian Kayvan 《Multimedia Tools and Applications》2018,77(2):2033-2055
Multimedia Tools and Applications - Nowadays, due to widespread usage of the Internet, digital contents are distributed quickly and inexpensively throughout the world. Watermarking techniques can... 相似文献
8.
Scientometrics - Counts of Mendeley readers may give useful evidence about the impact of published research. Although previous studies have found significant positive correlations between counts of... 相似文献
9.
Kayvan Sadeghy Navid Khabazi Seyed-Mohammad Taghavi 《International Journal of Engineering Science》2007,45(11):923-938
The present work is a theoretical investigation of the applicability of magnetic fields for controlling hydrodynamic separation in Jeffrey-Hamel flows of viscoelastic fluids. To achieve this goal, a local similarity solution was found for laminar, two-dimensional flow of a viscoelastic fluid obeying second-order/second-grade model as its constitutive equation with the assumption being made that the flow is symmetric and purely radial. These assumptions enabled a third-order nonlinear ODE to be obtained as the single equation governing the MHD flow of this particular fluid in flow through converging/diverging channels. With three physical boundary conditions available, Chebyshev collocation-point method was used to solve this ODE numerically. Results are presented in terms of parameters such as Reynolds number, Weissenberg number, channel half-angle, and the magnetic number. It was found that these parameters all have a profound effect on the velocity profiles in Jeffrey-Hamel flows. The effect of magnetic field was found to be more striking in that it is predicted to force fluid elements near the wall to exceed centerline velocity in converging channels and to suppress separation in diverging channels. Interestingly, the effect of the magnetic field in delaying flow separation is predicted to become more pronounced the higher the fluid’s elasticity. 相似文献
10.
Serban Puia-Negulescu Fanny Leboss Jean-Yves Mabrut Xavier Muller Guillaume Rossignol Teresa Antonini Domitille Erard Sylvie Radenne Marielle Guillet Jean-Christophe Souquet Kayvan Mohkam Mickael Lesurtel 《International journal of molecular sciences》2021,22(6)
Patients with nonresectable liver metastases from colorectal cancer have few therapeutic options and a dismal prognosis. Although liver transplantation for this indication has historically a poor reputation, recent advances in the field of chemotherapy and immunosuppression have paved the way to revisit the concept. New data have shown promising results that need to be validated in several ongoing clinical trials. Since liver grafts represent a scarce resource, several new tools are being explored to expand the donor pool for this indication. The purpose of this review is to present all current available data and perspectives about liver transplantation for nonresectable liver metastases from colorectal cancer. 相似文献