Papers by Ernesto Alejandro Hernández Escobedo
The monitoring and diagnostics of Industrial systems is increasing in complexity with larger volu... more The monitoring and diagnostics of Industrial systems is increasing in complexity with larger volume of data collected and with many methods and analytics able to correlate data and events. The setup and training of these methods and analytics are one of the impacting factors in the selection of the most appropriate solution to provide an efficient and effective service, that requires the selection of the most suitable data set for training of models with consequent need of time and knowledge. The study and the related experiences proposed in this paper describe a methodology for tracking features, detecting outliers and derive, in a probabilistic way, diagnostic thresholds to be applied by means of hierarchical models that simplify or remove the selection of the proper training dataset by a subject matter expert at any deployment. This method applies to Industrial systems employing a large number of similar machines connected to a remote data center, with the purpose to alert one or more operators when a feature exceeds the healthy distribution. Some relevant use cases are presented for an aeroderivative gas turbine covering also its auxiliary equipment, with deep dive on the hydraulic starting system. The results, in terms of early anomaly detection and reduced model training effort, are compared with traditional monitoring approaches like fixed threshold. Moreover, this study explains the advantages of this probabilistic approach in a business application like the fleet monitoring and diagnostic advanced services.
Volume 9: Oil and Gas Applications; Supercritical CO2 Power Cycles; Wind Energy, Jun 11, 2018
Several operating parameters for the control and protection of the units are acquired by the cont... more Several operating parameters for the control and protection of the units are acquired by the control and protection systems used in industrial applications. The use of these parameters in conjunction of physical models, empirical models and transfer functions (that represent digital replicas of the engine) allows for a broader scope of condition monitoring, taking into account the wing to wing process which spans from data acquisition to end user actionable insight. This paper describes 3 specific cases: 1) an algorithm based on the performance model of the overall GT used to monitor the axial compressor degradation and optimize the planned axial compressor water wash of an aero-derivative GT; 2) an analytic based on the flow function physic model used to monitor the clogging of the fuel nozzles in a heavy duty GT and to plan their maintenance; 3) an analytic based on a hybrid model used to monitor the axial thrust acting on a roller bearing of an aero-derivative GT and used to verify the status of the bearing and to plan its maintenance. Moreover, the paper provides details about the evaluation of the measurements, describes the model accuracy and explains how the results obtained are affected by these uncertainties and the methods used to mitigate these uncertainties. In addition, this paper shows a method to aggregate and weigh the monitoring of each single component and its own status into an overall health view.
Social Science Research Network, 2015
Drawing from social identity theory, this study investigated certified nurse assistant's perceive... more Drawing from social identity theory, this study investigated certified nurse assistant's perceived belongingness, attachment to their organizations, and intentions to leave their jobs. Healthcare reform was the public policy guiding this study. Our findings indicated affective commitment to the organization partially mediated the relationship between organizational identification and turnover intentions.
The Global Journal of Business Research, Aug 10, 2012
This paper presents the conclusions and implications of the research study based on responses fro... more This paper presents the conclusions and implications of the research study based on responses from a sample of 20 manufacturing leader-managers working in the states of California or Florida. This research also presents recommendations for further action followed by a summary of findings. Organizational policies and procedures are in place to ensure standards are implemented for an efficient and safe work environment for all employees. It is expected that employees understand such processes so they can meet the goals of the organizations. Organizations that embrace diversity are able to bring unique talents and ideas that will serve clients' needs. However, when language presents a barrier to communication, then management has to weigh whether it is placing itself in a position to do more harm than good for employees involved. Two questions were fundamental to the research: (1) How do leadermanagers share and transfer organizational knowledge to a linguistically diverse manufacturing workforce to prevent workplace injuries in their organization? (2) What are perceived challenges in sharing and transferring organizational knowledge in a linguistically diverse manufacturing work force to prevent workplace injuries in their organization? JEL: D8, D83
Western Journal of Emergency Medicine, 2021
Introduction: The clinical presentation of coronavirus disease 2019 (COVID-19) overlaps with many... more Introduction: The clinical presentation of coronavirus disease 2019 (COVID-19) overlaps with many other common cold and influenza viruses. Identifying patients with a higher probability of infection becomes crucial in settings with limited access to testing. We developed a prediction instrument to assess the likelihood of a positive polymerase chain reaction (PCR) test, based solely on clinical variables that can be determined within the time frame of an emergency department (ED) patient encounter. Methods: We derived and prospectively validated a model to predict SARS-CoV-2 PCR positivity in patients visiting the ED with symptoms consistent with the disease. Results: Our model was based on 617 ED visits. In the derivation cohort, the median age was 36 years, 43% were men, and 9% had a positive result. The median time to testing from the onset of initial symptoms was four days (interquartile range [IQR]: 2-5 days, range 0-23 days), and 91% of all patients were discharged home. The final model based on a multivariable logistic regression included a history of close contact (adjusted odds ratio [AOR] 2.47, 95% confidence interval [CI],
Journal of Information Assurance & Cybersecurity, 2016
The use of the Internet by terrorists has greatly contributed to international terrorism. The Int... more The use of the Internet by terrorists has greatly contributed to international terrorism. The Internet is a main strategic communication asset for terrorists who use online message boards and chat rooms to share information, coordinate attacks, spread propaganda, raise money, and recruit. The Internet gives terrorists a medium to legitimize, propagate, and intimidate citizens to their cause. Their strategies are based on careful analysis of human communications; thus, messages are adapted and carefully delivered to appeal to people who may need something to believe in. This study bridged the gap in knowledge by exploring, understanding, and explaining the perceptions of 10 American terrorist experts on how the use of the Internet by terrorists has shaped international terrorism. Findings of the study indicate that the use of the Internet by terrorists has shaped international terrorism, which resulted in major challenges for counterterrorism agencies in the United States and abroad due to the ability of terrorists to easily close, change, and create new websites or accounts. In addition, counterterrorism experts also have to deal with advanced encryption software and the anonymity of terrorist suspects. Terrorists are able to attract other like-minded individuals or sympathizers to their cause by using the Internet as the medium of communication. The research is significant in that it is directed at the U.S. intelligence community and international counterterrorism entities in order to make continuous improvements in the United States' homeland security by recognizing terrorist Internet tactics so they can quickly and effectively respond to them. This requires collaboration among counterterrorism agencies and organizations in the U.S. as well as collaboration among member states.
International Journal of Management and Marketing Research, 2013
Several safety-net hospitals have closed in the United States, but the scholarly literature does ... more Several safety-net hospitals have closed in the United States, but the scholarly literature does not adequately explain why. This study examines the relationship between the operational status (open or closed) of safety-net hospitals and unemployment, median household income, gross profit margin, efficiency ratio, operating margin, excess margin, and salary and benefit expenses per full-time equivalent. Study data were collected and analyzed by means of a logistic regression analysis. A significant relationship between hospital operational status and unemployment, operating margin, and salary and benefit expenses per full-time equivalent was indicated in this study. A safety-net hospital closure model was developed that showed that unemployment, operating margin, and salary and benefit expenses per full-time equivalent had a direct impact on hospital closures. Safety-net hospitals that experience upward trends in the unemployment rate in the areas they serve and have a poor operating margin and high salary and benefit expenses that make them more likely to close. This study provides supporting data to hospital administrators so decisions can be made to avoid future safety-net hospital closures. Information from this research can also provide legislators information and data as to why safety-net hospitals close and used as a tool for health care reform.
This paper presents the conclusions and implications of the research study based on responses fro... more This paper presents the conclusions and implications of the research study based on responses from a sample of 20 manufacturing leader-managers working in the states of California or Florida. This research also presents recommendations for further action followed by a summary of findings. Organizational policies and procedures are in place to ensure standards are implemented for an efficient and safe work environment for all employees. It is expected that employees understand such processes so they can meet the goals of the organizations. Organizations that embrace diversity are able to bring unique talents and ideas that will serve clients' needs. However, when language presents a barrier to communication, then management has to weigh whether it is placing itself in a position to do more harm than good for employees involved. Two questions were fundamental to the research: (1) How do leadermanagers share and transfer organizational knowledge to a linguistically diverse manufacturing workforce to prevent workplace injuries in their organization? (2) What are perceived challenges in sharing and transferring organizational knowledge in a linguistically diverse manufacturing work force to prevent workplace injuries in their organization? JEL: D8, D83
Psicoanalisis Revista De La Asociacion Psicoanalitica Colombiana, 2013
El bullying es un término norteamericano que aparece en el escenario alrededor de 1993, acuñado p... more El bullying es un término norteamericano que aparece en el escenario alrededor de 1993, acuñado por Dan Olweus, quien lo utiliza para describir el maltrato sistemático y continuo que se presenta en al ámbito escolar, [identificado inicialmente en el medio estadounidense], y que, si bien se podría definir como acoso, tiene nuevos componentes.
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Papers by Ernesto Alejandro Hernández Escobedo