Graph-based real-time fault diagnostics

A real-time fault detection and diagnosis capability is absolutely crucial in the design of large-scale space systems. Some of the existing AI-based fault diagnostic techniques like expert systems and qualitative modelling are frequently ill-suited for this purpose. Expert systems are often inadequately structured, difficult to validate and suffer from knowledge acquisition bottlenecks. Qualitative modelling techniques sometimes generate a large number of failure source alternatives, thus hampering speedy diagnosis. In this paper we present a graph-based technique which is well suited for real-time fault diagnosis, structured knowledge representation and acquisition and testing and validation. A Hierarchical Fault Model of the system to be diagnosed is developed. At each level of hierarchy, there exist fault propagation digraphs denoting causal relations between failure modes of subsystems. The edges of such a digraph are weighted with fault propagation time intervals. Efficient and restartable graph algorithms are used for on-line speedy identification of failure source components

Methodology for testing and validating knowledge bases

A test and validation toolset developed for artificial intelligence programs is described. The basic premises of this method are: (1) knowledge bases have a strongly declarative character and represent mostly structural information about different domains, (2) the conditions for integrity, consistency, and correctness can be transformed into structural properties of knowledge bases, and (3) structural information and structural properties can be uniformly represented by graphs and checked by graph algorithms. The interactive test and validation environment have been implemented on a SUN workstation

Research on an expert system for database operation of simulation-emulation math models. Volume 2, Phase 1: Results

A reference manual is provided for NESS, a simulation expert system. This manual gives user information regarding starting and operating NASA expert simulation system (NESS). This expert system provides an intelligent interface to a generic simulation program for spacecraft attitude control problems. A menu of the functions the system can perform is provided. Control repeated returns to this menu after executing each user request

Research on an expert system for database operation of simulation-emulation math models. Volume 1, Phase 1: Results

The results of the first phase of Research on an Expert System for Database Operation of Simulation/Emulation Math Models, is described. Techniques from artificial intelligence (AI) were to bear on task domains of interest to NASA Marshall Space Flight Center. One such domain is simulation of spacecraft attitude control systems. Two related software systems were developed to and delivered to NASA. One was a generic simulation model for spacecraft attitude control, written in FORTRAN. The second was an expert system which understands the usage of a class of spacecraft attitude control simulation software and can assist the user in running the software. This NASA Expert Simulation System (NESS), written in LISP, contains general knowledge about digital simulation, specific knowledge about the simulation software, and self knowledge

Development of a coupled expert system for the spacecraft attitude control problem

A majority of the current expert systems focus on the symbolic-oriented logic and inference mechanisms of artificial intelligence (AI). Common rule-based systems employ empirical associations and are not well suited to deal with problems often arising in engineering. Described is a prototype expert system which combines both symbolic and numeric computing. The expert system's configuration is presented and its application to a spacecraft attitude control problem is discussed

CFD analysis of fully decaying, partially decaying and partly swirl flow in round tubes with short length twisted tapes

CFD investigation was carried out to study the heat transfer characteristics of air flow inside a circular tube with a fully decaying, partially decaying and partly swirl flow. Four combinations of tube with twisted-tape inserts, half-length upstream twisted tape condition (HLUTT), half-length downstream twisted tape condition (HLDTT), full-length twisted tape (FLTT), inlet twisted tape (ILTT) are considered along with plain tube (PT) for comparison.. Three different twist parameter, ? = 0.14, 0.27, and 0.38, for twisted tape configuration have been studied for the above four configurations. 3D numerical simulation was performed for an analysis of heat transfer and fluid flow for turbulent regime. The results of CFD investigations of heat transfer, and friction characteristics are presented for the FLTT, HLUTT, HLDTT and the ILTT along with a velocity and temperature profiles analysis in comparison with the PT case. Keywords: HLUTT, HLDTT and FLTT, enhancement, Tape inserts, partially decaying swirl flow

Synthesis and characterization of novel 2, 2'-bipyrimidine fluorescent derivative for protein binding

<p>Abstract</p> <p>Background</p> <p>Fluorescent dyes with biocompatible functional group and good fluorescence behavior are used as biosensor for monitoring different biological processes as well as detection of protein assay. All reported fluorophore used as sensors are having high selectivity and sensitivity but till there is more demand to synthesized new fluorophore which have improved fluorescence properties and good biocompatibility.</p> <p>Results</p> <p>Novel 4, 4'-(1, 1'-(5-(2-methoxyphenoxy)-[2, 2'-bipyrimidine]-4, 6-diyl)bis(1<it>H</it>-pyrazol-3, 1-diyl)) dianiline fluorescent dye was synthesized by multistep synthesis from 2-phenylacetonitrile, 2-chloropyrimidine and 2-methoxyphenol. This dye has absorption at 379 nm with intense single emission at 497 nm having fairly good quantum yield (0.375) and Stokes shift. The intermediates and dye were characterized by FT-IR, ¹H NMR, ¹³C NMR and Mass spectral analysis. The pyrazole bipyrimidine based fluorescent dye possessing two amino groups suitable for binding with protein is reported. Its utility as a biocompatible conjugate was explained by conjugation with bovine serum albumin. The method is based on direct fluorescence detection of fluorophore-labelled protein before and after conjugation. Purified fluorescent conjugate was subsequently analyzed by fluorimetry. The analysis showed that the tested conjugation reaction yielded fluorescent conjugates of the dye through carbodiimide chemistry.</p> <p>Conclusion</p> <p>In summery synthesized fluorophore pyrazole-bipyrimidine has very good interaction towards protein bovine serum albumin and it acts as good candidate for protein assay.</p

IBX promoted one-pot condensation of β-naphthol, aldehydes, and 1,3-dicarbonyl compounds

Abstract An efficient and mild protocol has been developed for one-pot condensation of β-naphthol, aldehydes, and 1,3-dicarbolyl compounds in presence of o-iodoxybenzoic acid has been found to be an excellent catalyst for the synthesis of tetrahydrobenzo[a]xanthen-one, 1H-benzo[f]chromen-2-yl)-one via one-pot three-component condensation of β-naphthol, aldehydes, and 1,3-dicarbonyl compounds. Short reaction time, ambient conditions, simple workup, and high yield with selective manner are some of the striking features of the present protocol

Patient-Perceived Benefits and Limitations of Standard of Care Remote Symptom Monitoring During Cancer Treatment

Introduction Remote symptom monitoring (RSM) allows patients to electronically self-report symptoms to their healthcare team for individual management. Clinical trials have demonstrated overarching benefits; however, little is known regarding patient-perceived benefits and limitations of RSM programs used during patient care. Methods This prospective qualitative study from December 2021 to May 2023 included patients with cancer participating in standard-of-care RSM at the University of Alabama at Birmingham (UAB) in Birmingham, AL, and the Univeristy of South Alabama (USA) Health Mitchell Cancer Institute (MCI) in Mobile, AL. Semi-structured interviews focused on patient experiences with and perceptions surrounding RSM participation. Interviews occurred over the phone, via digital videoconference, or in person, at the convenience of the patient. Grounded theory was used to conduct content coding and identify recurring themes and exemplary quotes using NVivo. Results Forty patients (20 UAB, 20 MCI) were interviewed. Participants were predominately female (87.5%), aged 41-65 (50%), and married (57.5%). Data is consistent with local demographics, comprising mainly White (72.5%) and 27.5% Black individuals. Three main themes emerged regarding perceived benefits of RSM: (1) Facilitation of Proactive Management, identifying the patient’s needs and intervening earlier to alleviate symptom burden; (2) Promotion of Symptom Self-Management, providing patients autonomy in their cancer care; and (3) Improvement in Patient-Healthcare Provider Relationships, fostering genuine connections based on healthcare team’s responses. However, participants also noted Perceived Limitations of RSM; particularly when support of symptom management was unnecessary, ineffective, or felt impersonal. Conclusion This study focused on patient experiences when utilizing a RSM program while undergoing treatment for cancer and found benefits to its implementation that extended beyond symptom management. At the same time, patients noted drawbacks experienced during RSM, which can help with future tailoring of RSM programs. Patient perceptions should be regularly assessed and highlighted for successful and sustained implementation.Plain language summary Cancer and its treatment can cause patients to experience many forms of symptoms. This can have a major effect on their overall well-being: physically, mentally, and emotionally. Early symptom detection and management has been shown to significantly improve the quality of life of patients with cancer. Remote symptom monitoring (RSM) allow patients to report their symptoms to their healthcare team and receive personalized feedback and management from them, without having to leave the comfort of their home. Although previous studies have shown the overarching benefits of implementing RSM during care, little is known regarding how patients perceive its implementation. This research team wanted to gain a better understanding of perceptions patients had, whether good or bad, of RSM’s implementation while they were actively undergoing cancer care. A total of 40 patients were interviewed with patients commenting on RSM’s ability to facilitate proactive management, promote symptom self-management, and improve patient-healthcare provider relationships. Patients also had feelings that under certain circumstances, RSM did have some limitations. This study was able to help identify some of the perceived benefits and limitations to RSM implementation. This feedback will not only help to ensure the successful implementation of future RSM programs but will also let patients know that they are heard and that their feedback is pivotal