Search results for "Systems engineering"

Parallel distance transforms on pyramid machines: Theory and implementation

1990

Abstract A distance transform of a binary image is an array each of whose elements gives the distance from the corresponding pixel to the closest ‘1’ in the binary image. Distance transforms have uses in image matching and shape analysis, among other applications. We present a parallel algorithm for weighted distance transforms that runs particularly efficiently on hierarchical cellular-logic machines, a subclass of the architectures known as pyramid machines. The algorithm computes the 3–4 distance transform; however it can be readily adapted to the city-block (‘Manhattan’) and chessboard distance measures. The algorithm runs in O(M) time, for an M × M image. Since it avoids using arithmet…

Multiple Classifiers and Data Fusion for Robust Diagnosis of Gearbox Mixed Faults

2019

Detection and isolation of single and mixed faults in a gearbox are very important to enhance the system reliability, lifetime, and service availability. This paper proposes a hybrid learning algorithm, consisting of multilayer perceptron (MLP)- and convolutional neural network (CNN)-based classifiers, for diagnosis of gearbox mixed faults. Domain knowledge features are required to train the MLP classifier, while the CNN classifier can learn features itself, allowing to reduce the required knowledge features for the counterpart. Vibration data from an experimental setup with gearbox mixed faults is used to validate the effectiveness of the algorithms and compare them with conventional metho…

Novel Three-Phase Multilevel Inverter With Reduced Components for Low- and High-Voltage Applications

2021

In this article, a novel multilevel topology for three-phase applications, having three-level and hybrid N -level modular configurations, enabling low-, medium-, and high-voltage operations, is presented. The proposed topology has several attractive features, namely reduced component count, being capacitor-, inductor-, and diode-free, lowering cost, control-complexity, and size, and can operate in a wide range of voltages and powers. Selected simulation and experimental results are presented to verify the performance of the proposed topology. Further, the overall efficiency of the topology and loss distribution in switches are studied. Finally, the key features of the proposed topology in t…

Overview and experimental analysis of MC SPWM techniques for single-phase five level cascaded H-bridge FPGA controller-based

2016

This paper presents an overview and experimental analysis of the MC SPWM techniques for single-phase cascaded H-bridge inverter. The multilevel power converters are an alternative to traditional converters known as “three-level converters”. The voltage waveforms and the related frequency spectra, which have been obtained by simulation analysis in Matlab-Simulink environment, are here reported for all the proposed modulation techniques. The simulation results have been experimentally validated through means of a DC/AC, five-level, single-phase converter prototype with an appropriate test bench.

Building Information Modeling (BIM) Enabled Facilities Management Using Hadoop Architecture

2017

International audience; Protecting the safety of occupants and the environment is a core value within Facilities Management. Data acquisition systems such as wireless sensor networks can help to monitor facilities to reduce hazards such as fire, water flooding and burglaries. Building Information Modeling (BIM) is a revolutionary development that is reshaping the Architecture Engineering and Construction (AEC) industry. BIM is both a process and a technology, offers wide solutions for facilities management. In order to monitor and manage facilities data in a BIM based simulated environment, this work reports upon a development of a system that uses BIM software and a wireless sensor technol…

The Aquatic Surface Robot (AnSweR), a Lightweight, Low Cost, Multipurpose Unmanned Research Vessel

2021

Even though a few examples of aquatic surface robots exist, they are generally expensive, relatively large and heavy and tailored to custom-made hardware/software components that are not openly available to a broad public. In this work, the Aquatic Surface Robot (AnSweR), a newly-designed, lightweight, low cost, open-source, multipurpose unmanned research vessel is presented. The AnSweR features a lightweight and compact design that makes it fit in a backpack. Low-noise operation (in and above the surface) is achieved with a propulsion system based on two water-jets. Only affordable commercial-off-the-shelf (COTS) components are adopted. The primary goal of the AnSweR is to map underwater l…

Model Driven Architecture (MDA)

2003

D Sensor-Based Obstacle Detection Comparing Octrees and Point clouds Using CUDA

2012

This paper presents adaptable methods for achieving fast collision detection using the GPU and Nvidia CUDA together with Octrees. Earlier related work have focused on serial methods, while this paper presents a parallel solution which shows that there is a great increase in time if the number of operations is large. Two dierent models of the environment and the industrial robot are presented, the rst is Octrees at dierent resolutions, the second is a point cloud representation. The relative merits of the two dierent world model representations are shown. In particular, the experimental results show the potential of adapting the resolution of the robot and environment models to the task at h…

Interference Estimation in IEEE 802.11 Networks

2010

This article describes a technique for distinguishing and quantifying medium access control (MAC) and physical layer (PHY) interference in error-prone 802.11 networks. This technique, is fully distributed, allowing each station to estimate interference individually. The estimator is based on an extended Kalman filter coupled to a mechanism for revealing abrupt changes in state. The network state is a vector of two components, representing PHY interference, expressed in terms of channel-error rate, and MAC interference. Two distinct state models are considered. When PHY interference can be assumed to be constant for all stations, network congestion is expressed by the number of competing ter…

RTS2: Lessons learned from a widely distributed telescope network

2008

RTS2 (Remote Telescope System 2) is a highly modular open source telescope and observatory management software package. It evolved from RTS, which was developed in Python to control a telescope aimed at observing optical transients of γ ray burts. The development of a network system capable of operating robotic telescopes is both difficult and complicated. Along with continued software development one must be concerned with maintaining operations and obtaining results. This is a review of experiences gained building a network of robotic telescopes. It focuses on describing which issues are important during development of the robotic observatory software and requirements for future developme…