Search results for "Systems engineering"
showing 10 items of 1230 documents
A solution of the minimum-time velocity planning problem based on lattice theory
2018
For a vehicle on an assigned path, we find the minimum-time speed law that satisfies kinematic and dynamic constraints, related to maximum speed and maximum tangential and transversal acceleration. We present a necessary and sufficient condition for the feasibility of the problem and a simple operator, based on the solution of two ordinary differential equations, which computes the optimal solution. Theoretically, we show that the problem feasible set, if not empty, is a lattice, whose supremum element corresponds to the optimal solution.
Safety Protocols for Forensic Inspections in the Time of COVID-19: An Approach to Protect Practitioners
2022
The COVID-19 pandemic has impacted the entire world in ways that were unimaginable in 2019. It has changed how professionals work and interact with one another. To ensure the safety of experts and attorneys, forensic inspection procedures must evolve while still providing a reliable foundation for expert testimony. Traditional field inspections require attendees to be physically present and in generally close proximity. Inspecting artifacts may also require that individual components be serially examined by multiple experts, which increases the risk of transmitting the disease. The authors propose a new approach to forensic inspections aimed at protecting consultants from the biological ris…
Smart and resilient manufacturing in the wake of COVID-19.
2021
Since 2020, manufacturers have been facing unprecedented and extraordinary challenges with the COVID-19 outbreak, which severely disrupted manufacturing operations around the world. Some manufac- turers have shifted gears to help address dire shortages during the coronavirus pandemic. Others were thrown into deep unknowns and faced with the grim prospect of being closed down. We have seen a sprawling network of multinationals and local businesses step in to fill a void by using 3D printers to make personal protective equipment (PPE) such as face shields, respirator masks, nasal swabs and even ventilator parts. Large manufacturers attempted to rejig parts of their production lines to mass-pr…
The emerging role of 3D printing in the fabrication of detection systems
2021
Abstract 3D printing is fast evolving as an additive manufacturing technique that has been adopted in (bio)analytical science because of the ample variety of materials and technologies currently available for highly affordable prototyping. This review focuses on the unique characteristics of 3D printing for manufacturing of optical and electrochemical detection systems, and sampling interfaces for analytical purposes using fused deposition modelling, vat polymerization (stereolithography and digital light processing) and photopolymer inkjet printing. The majority of works surveyed within the time span of mid-2018 to mid-2020 encompassed the fabrication of several components of the detection…
Adaptive synchronization of master-slave systems with mixed neutral and discrete time-delays and nonlinear perturbations
2011
This paper investigates the delay-dependent adaptive synchronization problem of the master and slave structure of linear systems with both constant neutral and time-varying discrete time-delays and nonlinear perturbations based on the Barbalat lemma and matching conditions. An adaption law which includes the master-slave parameters is obtained by using the Lyapunov functional method and inequality techniques to synchronize the master-slave systems without the knowledge of upper bounds of perturbation terms. Particularly, it is shown that the synchronization speed can be controlled by adjusting the update gain of the synchronization signal. A numerical example has been given to show the effe…
Lung on a Chip Development from Off-Stoichiometry Thiol–Ene Polymer
2021
Institute of Solid-State Physics, University of Latvia as the Center of Excellence has received funding from the European Union’s Horizon 2020 Framework Programme H2020-WIDESPREAD-01-2016-2017-TeamingPhase2 under grant agreement No. 739508, project CAMART2. Finally, we would like to thank Biol. Kaspars Tars from Latvian Biomedical research and study center for giving us the opportunity to participate in this consortium and contribute to Latvian scientists’ effort in response to the COVID-19 pandemic.
International workshop on next generation gamma-ray source
2022
Journal of physics / G 49(1), 010502 (2022). doi:10.1088/1361-6471/ac2827
Steam sterilization processes affect the stability of clinical thermometers: Thermistor and prototypal FBG probe comparison
2020
Abstract Temperature is one of the most frequently measured physical quantities in clinical environment and a good biomarker of illness. The need for reusable probes, which have to be sterilized to prevent infections, requires the metrological qualification of thermometer probes in response to ageing effects induced by several sterilization processes. In this study, we investigated the effect of repeated sterilizations on both a commonly-used autoclavable thermistor probe and a prototypal Fiber Bragg Gratings (FBG) probe for temperature measurements. Findings highlighted a greater reliability of the proposed FBG probe than the commercial thermistor. Specifically, the FBG probe was able to w…
An Augmented Reality System for the Treatment of Acrophobia: The Sense of Presence Using Immersive Photography
2006
This paper describes an augmented reality (AR) system for the treatment of acrophobia. First, the technical characteristics of the original prototype are described. Second, the capacity of the immersive photography used in the AR system to provoke sense of presence in users is tested. Forty-one participants without fear of heights walked around a staircase in both a real environment and an immersive photography environment. Immediately after their experience, participants were given the SUS questionnaire to assess their subjective sense of presence. The users' scores in the immersive photography were very high. Results indicate that the acrophobic context can be useful for the treatment of…
Model Predictive Control for Shunt Active Filters With Fixed Switching Frequency
2016
This paper presents a modification to the classical Model Predictive Control algorithm, named Modulated Model Predictive Control, and its application to active power filters. The proposed control is able to retain all the advantages of a Finite Control Set Model Predictive Control whilst improving the generated waveforms harmonic spectrum. In fact a modulation algorithm, based on the cost function ratio for different output vectors, is inherently included in the MPC. The cost function-based modulator is introduced and its effectiveness on reducing the current ripple is demonstrated. The presented solution provides an effective and straightforward single loop controller, maintaining an excel…