K-Space Trajectory Design for Reduced MRI Scan Time

This article presents an algorithm for multi-objective optimization that blends together a number of heuristics. A population of agents combines heuristics that aim at exploring the search space both globally and in a neighbourhood of each agent. These heuristics are complemented with a combination of a local and global archive. The novel agent-based algorithm is tested at first on a set of standard problems and then on three specific problems in space trajectory design. Its performance is compared against a number of state-of-the-art multi-objective optimization algorithms that use the Pareto dominance as selection criterion: non-dominated sorting genetic algorithm (NSGA-II), Pareto archived evolution strategy (PAES), multiple objective particle swarm optimization (MOPSO), and multiple trajectory search (MTS). The results demonstrate that the agent-based search can identify parts of the Pareto set that the other algorithms were not able to capture. Furthermore, convergence is statistically better although the variance of the results is in some cases higher.

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Analysis of Some Global Optimization Algorithms for Space Trajectory Design

Journal of Spacecraft and Rockets ◽

10.2514/1.45742 ◽

2010 ◽

Vol 47 (2) ◽

pp. 334-344 ◽

Cited By ~ 41

Author(s):

M. Vasile ◽

E. Minisci ◽

M. Locatelli

Keyword(s):

Global Optimization ◽

Optimization Algorithms ◽

Trajectory Design ◽

Space Trajectory Design

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A hybrid, self-adjusting search algorithm for optimal space trajectory design

Advances in Space Research ◽

10.1016/j.asr.2012.04.026 ◽

2012 ◽

Vol 50 (4) ◽

pp. 471-488 ◽

Cited By ~ 9

Author(s):

Andrea Bolle ◽

Christian Circi

Keyword(s):

Search Algorithm ◽

Trajectory Design ◽

Space Trajectory Design ◽

Optimal Space

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Assessment of Patients’ Knowledge, Perception and Safety Regarding MRI Scan

Journal of Manmohan Memorial Institute of Health Sciences ◽

10.3126/jmmihs.v6i1.30532 ◽

2020 ◽

Vol 6 (1) ◽

pp. 3-19 ◽

Cited By ~ 1

Author(s):

Susmita Shrestha ◽

Bibek Khadka

Keyword(s):

Demographic Data ◽

College Teaching ◽

Educational Status ◽

Cross Sectional Study ◽

Patient Perception ◽

Patient Comfort ◽

Mri Scan ◽

Cross Sectional ◽

Medical College ◽

Scan Time

Correction: The page numbers on this article were changed from 4-20 to 3-19 on 31/08/2020. Introduction: We presume that the knowledge of patients about Magnetic Resonance imaging (MRI) scan is of utmost importance for smooth workflow, patient comfort, patients’ safety and to mitigate patients’ compliance and save valuable scan time. Therefore, the purpose ofthis study was to determine the awareness of patients undergoing MRI scan regarding Knowledge, Perception and Safety. Methods: This descriptive cross-sectional study was carried out in Chitwan Medical College Teaching Hospital from April to September, 2018. Total of 310 patients referred to undergo MRI scan were assessed by a questionnaire form covering 4 parts: Part 1- aimed to gather the socio demographic data such as age, sex, occupation and educational status of patients, Part 2- included the knowledge regarding MRI and its safety, Part 3- comprised the patient perception before MRI scan and Part 4 constituted the patient perception after MRI scan.The form was filled by an investigator oneself in a face to face interview with the patients. Results: Among 310 patients, 35.2% were illiterate and 19.4% graduated from high school. Majority of 85.5% patients answered that MRI uses harmful ionizing radiation like CT scan and radiography. Almost 43 patients who answered MRI functions in disease treatment also answered decreased in pain after MRI scan (Male = 15 and Female = 28) were in age group between 25 years and 50 years. This study also revealed that majority of 26.8% (i.e. n = 83) patients faced problem as claustrophobia along with anxiety during the scan, out of which 13 patients have history of previous MRI scan. Conclusions: In our study decrease in pain was higher in diagnosis and treatment answer. Majority of the patients faced anxiety along with claustrophobia during the MRI scan. Assessment of patient knowledge, perception and safety regarding MRI scan can be the key to increase patient compliance and save valuable scan time.

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