In this paper, a broadband 5G MIMO mobile antenna with a shared radiator is proposed. The working band range is 3.3-6.0GHz, covering n77, n78, n79 and WLAN 5G working bands, which can meet a large number of applicatio...
详细信息
This article develops a discrete time dynamic feedback model of a congestion control system for a simple network with TCP Westwood (TCPW) connections and a single bottleneck link with random early detection (RED) ...
详细信息
This article develops a discrete time dynamic feedback model of a congestion control system for a simple network with TCP Westwood (TCPW) connections and a single bottleneck link with random early detection (RED) gateway. By using this model, the nonlinear dynamics of the TCPW/RED network are analyzed and its parameter sensitivities are studied. It is shown that periodic doubling bifurcation occurs when the RED control parameters or other parameters are varied. By theoretical analysis, the fixed point, the critical value of parameters and the nature of the bifurcation are determined. Moreover, by using bifurcation diagrams and Lyapunov exponent, the result of theoretical analysis is validated and the bifurcation and chaotic phenomena are numerically studied of the congestion control system with TCPW connections and RED gateway.
In the paper, the authors derive the method of splitting plane wave FDTD (SP-FDTD) method for initiation of plane wave sources in the total-field and scattered-field (TF/SF) formulation of 3D FDTD (2, 4) scheme. By sp...
详细信息
The high-order finite-difference time-domain (HO-FDTD) technique is used in the simulation of ground-penetrating radar modeling in three dimensions (3-D), which can improve accuracy and reduce the error caused by nume...
详细信息
The finite difference time domain (FDTD) is a powerful method in electromagnetic simulation and also widely used in research of the metamaterials recently. In this paper a novel FDTD method based on split operator is ...
详细信息
Social media systems are very popular in today's dynamic web. One of the famous social media systems is Twitter, in which peoples used to share their personal ideas about current issues with their friends. This wo...
详细信息
ISBN:
(纸本)9781509064151;9781509064144
Social media systems are very popular in today's dynamic web. One of the famous social media systems is Twitter, in which peoples used to share their personal ideas about current issues with their friends. This work focuses on the problem of discovering a user's interest over time on twitter. Previous approaches have used to model the user topic of interest on twitter by building the profile of the users, that contain the words which can be used the user in his or her conversions with other users, but on twitter users used the noisy words which does not represent the correct topics or topic related to interest. This model has extended by a novel framework by using twitter user model. This model uses the latent topic variable to indicate the relatedness of the topic with any user. In this work, we propose a Temporal User Topic(TUT) approach which can consider the text of tweet by any user and time of the tweet. The proposed approach is used to discover topically related Users for different time periods. We also show how the interests and relationships of these users are changeovers a time period.
A novel symplectic algorithm is proposed to solve the Maxwell Schrodinger (M-S) system for investigating light-matter interaction. Using the fourth-order symplectic integration and fourth-order collocated differences,...
详细信息
A novel symplectic algorithm is proposed to solve the Maxwell Schrodinger (M-S) system for investigating light-matter interaction. Using the fourth-order symplectic integration and fourth-order collocated differences, M-S equations are discretized in temporal and spatial domains, respectively. The symplectic finite-difference time-domain (SFDTD) algorithm is developed for accurate and efficient study of coherent interaction between electromagnetic fields and artificial atoms. Particularly, the Dirichlet boundary condition is adopted for modeling the Rabi oscillation problems under the semiclassical framework. To implement the Dirichlet boundary condition, image theory is introduced, tailored to the high-order collocated differences. For validating the proposed SFDTD algorithm, three-dimensional numerical studies of the population inversion in the Rabi oscillation are presented. Numerical results show that the proposed high-order SFDTD(4, 4) algorithm exhibits better numerical performance than the conventional FDTD(2, 2) approach at the aspects of accuracy and efficiency for the long-term simulation. The proposed algorithm opens up a promising way toward a high-accurate energy-conservation modeling and simulation of complex dynamics in nanoscale light-matter interaction.
Medical visual question answering is crucial for effectively interpreting medical images containing clinically relevant information. This study proposes a method called MedBLIP (Medical Treatment Bootstrapping Languag...
Medical visual question answering is crucial for effectively interpreting medical images containing clinically relevant information. This study proposes a method called MedBLIP (Medical Treatment Bootstrapping Language-Image Pretraining) to tackle visual language generation tasks related to chest X-rays in the medical field. The method combine an image encoder with a large-scale language model, and effectively generates medical question-answering text through a strategy of freezing the image encoder based on the BLIP-2 model. Firstly, chest X-ray images are preprocessed, and an image sample generation algorithm is used to enhance the text data of doctor-patient question-answering, thereby increasing data diversity. Then, a multi-layer convolutional image feature extractor is introduced to better capture the feature representation of medical images. During the fine-tuning process of the large language generation model, a new unfreezing strategy is proposed, which is to unfreeze different proportions of the weights of the fully connected layer to adapt to the data in the medical field. The image feature extractor is responsible for extracting key features from images, providing the model with rich visual information, while the text feature extractor accurately captures the essential requirements of the user's question. Through their synergistic interaction, the model can more effectively integrate medical images and user inquiries, thereby generating more accurate and relevant output content. The experimental results show that unfreezing 31.25% of the weights of the fully connected layer can significantly improve the performance of the model, with ROUGE-L reaching 66.12%, and providing a more accurate and efficient answer generation solution for the medical field. The method of this study has potential applications in the field of medical language generation tasks. Although the proposed model cannot yet fully replace human radiologists, it plays an indispensable role
In this paper, the periodic structures are simulated by the split-field finite difference time domain (FDTD) method. By using this method, a set of auxiliary elements are introduced to represent the discretization of ...
详细信息
Vehicular Ad Hoc Networks (VANETs) can provide participants with security services and entertainment information during the driving. To guarantee correct and smooth operations of VANETs, it is necessary to achieve eff...
详细信息
暂无评论