scholarly journals Terminal-Area Aircraft Intent Inference Approach Based on Online Trajectory Clustering

2015 ◽  
Vol 2015 ◽  
pp. 1-11
Author(s):  
Yang Yang ◽  
Jun Zhang ◽  
Kai-quan Cai
Keyword(s):  
Real Time ◽  
State Of The Art ◽  
Air Traffic ◽  
The State ◽  
Traffic Situation ◽  
Trajectory Clustering ◽  
The Real ◽  
Preliminary Results ◽  
Intent Modeling ◽  
Terminal Area

Terminal-area aircraft intent inference (T-AII) is a prerequisite to detect and avoid potential aircraft conflict in the terminal airspace. T-AII challenges the state-of-the-art AII approaches due to the uncertainties of air traffic situation, in particular due to the undefined flight routes and frequent maneuvers. In this paper, a novel T-AII approach is introduced to address the limitations by solving the problem with two steps that are intent modeling and intent inference. In the modeling step, an online trajectory clustering procedure is designed for recognizing the real-time available routes in replacing of the missed plan routes. In the inference step, we then present a probabilistic T-AII approach based on the multiple flight attributes to improve the inference performance in maneuvering scenarios. The proposed approach is validated with real radar trajectory and flight attributes data of 34 days collected from Chengdu terminal area in China. Preliminary results show the efficacy of the presented approach.

A Survey of Real-Time Industrial Wireless LAN Research

2015 ◽  
Vol 738-739 ◽  
pp. 1105-1110 ◽  
Author(s):  
Yuan Qing Qin ◽  
Ying Jie Cheng ◽  
Chun Jie Zhou
Keyword(s):  
Real Time ◽  
Future Development ◽  
Wireless Lan ◽  
State Of The Art ◽  
The State ◽  
Local Networks ◽  
The Real ◽  
Time Requirements ◽  
And Performance ◽  
Fundamental Mechanism

This paper mainly surveys the state-of-the-art on real-time communicaton in industrial wireless local networks(WLANs), and also identifys the suitable approaches to deal with the real-time requirements in future. Firstly, this paper summarizes the features of industrial WLANs and the challenges it encounters. Then according to the real-time problems of industrial WLAN, the fundamental mechanism of each recent representative resolution is analyzed in detail. Meanwhile, the characteristics and performance of these resolutions are adequately compared. Finally, this paper concludes the current of the research and discusses the future development of industrial WLANs.

ANALYZING THE REAL-TIME PROPERTIES OF A U.S. NAVY SIGNAL PROCESSING SYSTEM

2001 ◽  
Vol 08 (04) ◽  
pp. 301-322 ◽  
Author(s):  
STEVE GODDARD ◽  
KEVIN JEFFAY
Keyword(s):  
Signal Processing ◽  
Real Time ◽  
State Of The Art ◽  
Low Frequency ◽  
Processing System ◽  
The State ◽  
Signal Processing System ◽  
Processing Application ◽  
The Real ◽  
On Line

The state of the art in verifying the real-time requirements of applications developed using general processing graph models relies on simulation or off-line scheduling. We extend the state of the art by presenting analytical methods that support the analysis of cyclic processing graphs executed with on-line schedulers. We show that it is possible to compute the latency inherent in a processing graph independent of the hardware hosting the application. We also show how to compute the real-time execution rate of each node in the graph. Using the execution rate of each node and the time it takes per execution on a given processor, the resulting CPU utilization can be computed, as shown here for the Directed Low Frequency Analysis and Recording (DIFAR) acoustic signal processing application from the Airborne Low Frequency Sonar (ALFS) system of the SH-60B LAMPS MK III anti-submarine helicopter.

scholarly journals Performance optimization of task intensive real time applications on multicore ECUs - a hybrid scheduler

2019 ◽  
Vol 8 (2) ◽  
pp. 114
Author(s):  
Geetishree Mishra ◽  
Rajeshwari Hegde
Keyword(s):  
Real Time ◽  
Performance Optimization ◽  
State Of The Art ◽  
Multicore Processors ◽  
Scheduling Algorithm ◽  
Electronic System ◽  
Current Approach ◽  
The State ◽  
Thermal Dissipation ◽  
The Real

In the current approach of Automotive electronic system design, the multicore processors have prevailed to achieve high computing performance at low thermal dissipation. Multicore processors offer functional parallelism that helps in meeting the safety critical requirements of vehicles. The number of ECUs in high-end cars could be reduced by conglomerating more functions into a multicore ECU. AUTOSAR stack has been designed to support the applications developed for multicore ECUs. The real challenges lie in adapting new design methods while developing sophisticated applications with multicore constraints. It is imperative to utilize the most of multicore computational capability towards enhancing the overall performance of ECUs. In this context the scheduling of the real time multitasking software components by the operating system is one of the key issues to be addressed. In this paper, the state of the art scheduling algorithm is reviewed and its merits and limitations are identified. A hybrid scheduler has been proposed, tested and compared with the state of the art algorithm that offers better performance in terms of CPU utilization, average response time and deadline missing rate both in normal and high load conditions.

scholarly journals Single-Satellite Integrated Navigation Algorithm Based on Broadband LEO Constellation Communication Links

2021 ◽  
Vol 13 (4) ◽  
pp. 703
Author(s):  
Lvyang Ye ◽  
Yikang Yang ◽  
Xiaolun Jing ◽  
Jiangang Ma ◽  
Lingyu Deng ◽  
...  
Keyword(s):  
Real Time ◽  
Satellite Communication ◽  
The State ◽  
Earth Orbit ◽  
Integrated Navigation ◽  
Location Services ◽  
The Real ◽  
Navigation Algorithm ◽  
Communication Links ◽  
Leo Satellite

With the rapid development of satellite technology and the need to satisfy the increasing demand for location-based services, in challenging environments such as indoors, forests, and canyons, there is an urgent need to improve the position accuracy in these environments. However, traditional algorithms obtain the position solution through time redundancy in exchange for spatial redundancy, and they require continuous observations that cannot satisfy the real-time location services. In addition, they must also consider the clock bias between the satellite and receiver. Therefore, in this paper, we provide a single-satellite integrated navigation algorithm based on the elimination of clock bias for broadband low earth orbit (LEO) satellite communication links. First, we derive the principle of LEO satellite communication link clock bias elimination; then, we give the principle and process of the algorithm. Next, we model and analyze the error of the system. Subsequently, based on the unscented Kalman filter (UKF), we model the state vector and observation vector of our algorithm and give the state and observation equations. Finally, for different scenarios, we conduct qualitative and quantitative analysis through simulations, and the results show that, whether in an altimeter scenario or non-altimeter scenario, the performance indicators of our algorithm are significantly better than the inertial navigation system (INS), which can effectively overcome the divergence problem of INS; compared with the medium earth orbit (MEO) constellation, the navigation trajectory under the LEO constellation is closer to the real trajectory of the aircraft; and compared with the traditional algorithm, the accuracy of each item is improved by more than 95%. These results show that our algorithm not only significantly improves the position error, but also effectively suppresses the divergence of INS. The algorithm is more robust and can satisfy the requirements of cm-level real-time location services in challenging environments.

The State of the Art in Real-Time Range Mapping — A Panel Discussion

1990 ◽  
pp. 341-346
Author(s):  
Joseph Wilder ◽  
J.K. Aggarwal ◽  
P. Besl ◽  
T. Kanade ◽  
A. Slotwinski ◽  
...  
Keyword(s):  
Real Time ◽  
State Of The Art ◽  
Panel Discussion ◽  
The State ◽  
Time Range

Open Judiciary Worldwide

2020 ◽  
pp. 1207-1221
Author(s):  
Carlos E. Jiménez-Gómez
Keyword(s):  
Exploratory Study ◽  
Success Factors ◽  
State Of The Art ◽  
Common Law ◽  
The State ◽  
Preliminary Results ◽  
Critical Success ◽  
Learning Practices ◽  
The Common ◽  
Research Questions

Despite its origins, openness in the judiciary has expanded beyond transparency and, therefore, beyond the common law open justice principle. Several initiatives worldwide are echoing this trend and a new term, open judiciary, is arising as a way to address openness in the justice field. This chapter gives an overview of open judiciary initiatives worldwide, focusing on some of the most successful, in order to identify drivers of adoption, critical success factors, and preliminary results. The research is embedded in a broader exploratory study on the state of the art of open judiciary. The chapter is addressed to answer two of the research questions: What are some learning practices that can be identified worldwide in relation to openness in the judiciary? What are some of the most important lessons that can be learnt from these practices?

scholarly journals Real-Time Docking Ring Detection Based on the Geometrical Shape for an On-Orbit Spacecraft

Sensors ◽  
2019 ◽  
Vol 19 (23) ◽  
pp. 5243
Author(s):  
Zhang ◽  
Pan ◽  
Ma
Keyword(s):  
Least Squares ◽  
Real Time ◽  
Detection Method ◽  
State Of The Art ◽  
The State ◽  
Selection Strategy ◽  
Geometrical Shape ◽  
Automatic Capture ◽  
Rendezvous And Docking ◽  
Real Time Application

Docking ring is a circular hatch of spacecraft that allows servicing spacecraft to dock in various space missions. The detection of the ring is greatly beneficial to automatic capture, rendezvous and docking. Based on its geometrical shape, we propose a real-time docking ring detection method for on-orbit spacecraft. Firstly, we extract arcs from the edge mask and classify them into four classes according to edge direction and convexity. By developing the arc selection strategy, we select a combination of arcs possibly belonging to the same ellipse, and then estimate its parameters via the least squares fitting technique. Candidate ellipses are validated according to the fitness of the estimation with the actual edge pixels. The experiments show that our method is superior to the state-of-the-art methods, and can be used in real time application. The method can also be extended to other applications.

scholarly journals Exploiting Visibility Information in Surface Reconstruction to Preserve Weakly Supported Surfaces

2014 ◽  
Vol 2014 ◽  
pp. 1-20 ◽  
Author(s):  
Michal Jancosek ◽  
Tomas Pajdla
Keyword(s):  
Surface Reconstruction ◽  
Free Space ◽  
State Of The Art ◽  
The State ◽  
Real Object ◽  
Reconstruction Method ◽  
The Real ◽  
Model Free ◽  
Novel Method ◽  
Different Levels

We present a novel method for 3D surface reconstruction from an input cloud of 3D points augmented with visibility information. We observe that it is possible to reconstruct surfaces that do not contain input points. Instead of modeling the surface from input points, we model free space from visibility information of the input points. The complement of the modeled free space is considered full space. The surface occurs at interface between the free and the full space. We show that under certain conditions a part of the full space surrounded by the free space must contain a real object also when the real object does not contain any input points; that is, an occluder reveals itself through occlusion. Our key contribution is the proposal of a new interface classifier that can also detect the occluder interface just from the visibility of input points. We use the interface classifier to modify the state-of-the-art surface reconstruction method so that it gains the ability to reconstruct weakly supported surfaces. We evaluate proposed method on datasets augmented with different levels of noise, undersampling, and amount of outliers. We show that the proposed method outperforms other methods in accuracy and ability to reconstruct weakly supported surfaces.

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