We propose a cost effective digitized radio-over-fiber (D-RoF) system employing a sigma delta modulation (SDM) and a bidirectional transmission technique using phase modulated downlink and intensity modulated uplink. ...
详细信息
ISBN:
(纸本)9781510604797;9781510604803
We propose a cost effective digitized radio-over-fiber (D-RoF) system employing a sigma delta modulation (SDM) and a bidirectional transmission technique using phase modulated downlink and intensity modulated uplink. SDM is transparent to different radio access technologies and modulation formats, and more suitable for a downlink of wireless system because a digital to analog converter (DAC) can be avoided at the base station (BS). Also, Central station and BS share the same light source by using a phase modulation for the downlink and an intensity modulation for the uplink transmission. Avoiding DACs and light sources have advantages in terms of cost reduction, power consumption, and compatibility with conventional wireless network structure. We have designed a cost effective bidirectional D-RoF system using a low pass SDM and measured the downlink and uplink transmission performance in terms of error vector magnitude, signal spectra, and constellations, which are based on the 10MHz LTE 64-QAM standard.
With the development of sensor technology, automatic driving technology primarily uses LiDAR and cameras to realize 3D object detection tasks. In general, lidar can provide adequate geometric position information, and...
With the development of sensor technology, automatic driving technology primarily uses LiDAR and cameras to realize 3D object detection tasks. In general, lidar can provide adequate geometric position information, and RGB cameras can provide rich semantic information. Therefore, using a multi-modal strategy to fuse point clouds and RGB images can theoretically improve the detection performance. During the training process of 3D object detection pipeline with multi-modal fusion, 3D-IoU (3D Intersection-over-Union) based loss term is usually utilized to guide the learning of network parameters. However, the conventional 3D-IoU loss is relatively coarse, and it cannot accurately calculate the IoU between the genuine 3D bounding box and the predicted 3D bounding box. Therefore, we use Gaussian distribution to approximate the 3D-IoU score in the training process to acquire a 3D object detector with higher attributes. Our approach was experimented on the KITTI dataset, and the experimental results show that using Gaussian distribution to approximate the 3D-IoU loss can effectively improve the performance of 3D object detection.
The usage and number of available video conferencing (VC) applications are rising as the high-bandwidth, low latency networks on which they depend become increasingly prevalent. Since VC applications support real-time...
详细信息
The usage and number of available video conferencing (VC) applications are rising as the high-bandwidth, low latency networks on which they depend become increasingly prevalent. Since VC applications support real-time human interaction, problems with performance that impair interactivity are social issues. Currently, performance measurements cannot easily be obtained due to the proprietary nature of VC applications, however, such measurements would be useful because they enable researchers to easily evaluate the performance impact of architectural and design decisions, quantitatively compare VC applications, and determine service level agreement (SLA) compliance. In this paper, we present a tool called Av Cloak that is capable of measuring several key performance metrics in proprietary VC applications: mouth-to-ear latency and jitter, capture-to-display latency and jitter, and audio-visual synchronization skew. AvCloak takes these measurements by wrapping ("cloaking") the VC application's audio/video inputs/outputs and transmitting timestamp data through them. At the sender side, AvCloak synthesizes media data encoding timestamps and feeds them to the VC application's media inputs, while at the receiver side, AvCloak decodes timestamps from the VC application's media outputs. Since AvCloak interacts with the target VC application only through its media inputs and outputs, it treats the target application as a black box and is thus applicable to arbitrary VC applications. We provide extensive analyses to measure AvCloak's overhead and show how to improve accuracy in measurements using two popular VC applications: Skype and Google+ Hangouts.
In this paper we have developed a statistical pattern classifier, which applies the optimal interpolative network (OI-net), derived by one of the authors based on a generalized Fock space formulation. The classifier i...
详细信息
In this paper we have developed a statistical pattern classifier, which applies the optimal interpolative network (OI-net), derived by one of the authors based on a generalized Fock space formulation. The classifier is a 3-stage algorithm, which uses an editing operation on the training set, and iteratively updates the net structure till the final solution is obtained. Its performance is demonstrated on two examples.< >
As the use of the Internet continues to grow explosively, edge computing has emerged as an important technique for delivering Web content over the Internet. Edge computing moves data and computation closer to end-user...
详细信息
ISBN:
(纸本)9780769529950
As the use of the Internet continues to grow explosively, edge computing has emerged as an important technique for delivering Web content over the Internet. Edge computing moves data and computation closer to end-users for fast local access and better load distribution. Current approaches use caching, which does not work well with highly dynamic data. In this paper we propose a different approach to enhance edge computing. Our approach lies in a wide area data replication protocol that enables the delivery of dynamic content with full consistency guarantees and with all the benefits of edge computing, such as low latency and high scalability. What is more, the proposed solution is fully transparent to the applications that are brought to the edge. Our extensive evaluations in a real wide area network using TPC-W show promising results.
The exponential availability of protein sequences has led to the dominance of the pretraining-then-finetuning paradigm for protein function prediction. However, finetuning a pretrained protein language model for diver...
详细信息
ISBN:
(纸本)9783031723520;9783031723537
The exponential availability of protein sequences has led to the dominance of the pretraining-then-finetuning paradigm for protein function prediction. However, finetuning a pretrained protein language model for diverse downstream tasks requires annotated protein data tailored to each task. To avoid the redundant individual finetuning, we propose a methodology that unifies various Protein function prediction tasks via Text Matching (named ProTeM). This method first transforms simple numeric or category labels from disparate protein datasets into textual descriptions, imbued with rich semantics. We then harness a pretrained large language model, which is proficient in comprehensive language understanding, to capture intrinsic interconnections among varied protein functions and facilitate the alignment between text and protein. During inference, we employ the paradigm of text matching to predict the protein functionalities. Extensive experiments demonstrate that ProTeM achieves performance on par with individually finetuned models, and outshines the model based on conventional multi-task learning. Moreover, ProTeM unveils an enhanced capacity for protein representation, surpassing state-of-the-art PLMs.
This paper demonstrates a fuzzy sliding mode control (FSMC) scheme for a static reactive power (VAR) compensator (SVC) to improve the damping of a synchronous generator. A robust sliding regime is derived to guarantee...
详细信息
ISBN:
(纸本)0780319680
This paper demonstrates a fuzzy sliding mode control (FSMC) scheme for a static reactive power (VAR) compensator (SVC) to improve the damping of a synchronous generator. A robust sliding regime is derived to guarantee the stability of the FSMC with parameter uncertainties. Two types of FSMC-fuzzy switching gain compensation and fuzzy control signal compensation, are recommended to regulate the reactive power of the SVC. A synchronous generator system with the proposed FSMC-SVC has been studied and its dynamic responses are simulated. And the results show that the suggested FSMC possesses the advantages of fuzzy control and sliding mode control, e.g., insensitivity to parameter variations and load disturbances. The dynamic performance of the synchronous machine system can be improved dramatically over a wide range of operating condition. In these control schemes, the reducing switches control are adopted for simplification.< >
The charging of the workpiece in electron beam direct writing processes has been identified as a problem that disturbs the electron beam and causes pattern displacement error. In this paper the electron beam deflectio...
详细信息
The charging of the workpiece in electron beam direct writing processes has been identified as a problem that disturbs the electron beam and causes pattern displacement error. In this paper the electron beam deflection caused by surface charging is evaluated by the SIMON and MATHEMATICA simulation programs. Isolated charged patterns of different geometry are simulated as electrodes with given potentials in SIMION to calculate the extent of beam deflection, while secondary electron emission yield and beam dosage are assigned in MATHEMATICA programming for determination of surface potential and spatial field, from which the beam deflection is then calculated. The simulation results are in good agreement with each other and they are compared with values available in literature. The initial charge content along with the pattern dimensions chosen in simulation are found to be the major factors that determine the extent of beam deflection. The limitation of SIMION simulation on the beam deflection is also discussed.
The proposed construction of a tidal barrage to generate electricity in the Severn Estuary between England and Wales could provide an economically attractive and environmentally acceptable way of supplying up to 7% of...
详细信息
ISBN:
(纸本)9781842196199
The proposed construction of a tidal barrage to generate electricity in the Severn Estuary between England and Wales could provide an economically attractive and environmentally acceptable way of supplying up to 7% of England and Wales's electricity consumption with low-cost, low-carbon electricity by 2020. Thus helping the UK government to meet its obligation under its current Climate Change Policy and specifically those contained within the Renewable Energy Strategy (2009) of achieving 15% of energy supply from renewables by 2015. This development will however have a huge impact upon 63,000 overwintering birds;destroy protected areas of wetland;and alter the estuarine ecosystem beyond repair. If projects like this were permitted, the UK would have to take compensatory measures to ensure the overall coherence of Natura 2000 was protected (Art. 6(3) & 6(4) of the EC Habitats Directive 92/43/EEC). Will these compensatory measures be effective considering that we do not fully appreciate the role and function of ecosystem services provided by areas such as those around the River Severn? Perhaps more importantly are we prepared to gamble that their loss will be less damaging to us than the impact from future climate change? This then obliges us to question the weight given to conservation of species and habitats in an era of economic transformation and climate change obligation. We need to ask ourselves if we truly are at a point in our evolution where we will be making decisions of whether or not to sacrifice one good for another greater good (Alder, J. and Wilkinson, D., (1999). Given the overwhelming legal protection afforded to this area one of the issues that needs to be explored is how such a proposal was even considered? Have we approached the moment when Article 6(4) of the Habitats Directive 'Imperative Reasons of Overriding Public Importance' (IROP) will include combating climate change? If such a project is allowed to go ahead in this area, does the preventio
暂无评论