Investigation of thermal properties and latent heat reduction mechanisms in nanofluid phase change materials

The thermal properties of paraffin-based nanofluids have been examined to investigate the use of enhanced phase change materials (PCMs) for thermal energy storage (TES). PCMs are promising for TES applications, but low thermal conductivity limits their rate of heat exchange with a working fluid. The nanofluid approach has been established as a method of thermal conductivity enhancement, but effects of particle addition on other thermal properties affecting TES are relatively ignored. Significant reduction in latent heat of fusion below traditional effective medium theory has been observed in nanofluids. An experimental study of paraffin nanofluids, containing various diameter multi-walled carbon nanotubes, has been conducted to investigate these findings. Results demonstrate that the magnitude of nanofluid latent heat reduction increases for smaller diameter particles in suspension. A method to approximate nanofluid latent heat of fusion is presented, considering the diameter-dependent reduction observed. Three possible mechanisms – interfacial liquid layering, Brownian movement, and particle clustering – are examined to explain further reduction in latent heat, through weakening of molecular bond structure. Although interfacial layering effects and Brownian motion contribute some reduction, experimental evidence suggests that particle clustering is the only mechanism capable of explaining the degree of latent heat reduction observed. Additional research is needed to explore these proposed mechanisms. Nanofluid latent heat and effective thermal conductivity were analyzed collectively to investigate the effects of particle size on PCM energy storage performance. It is shown that while particle diameter significantly impacts nanofluid latent heat, thermal conductivity exhibits a negligible size dependency. Governing equations for a finite element model of nanofluid phase change is presented, as a method of quantifying PCM energy storage performance. Measured and approximated thermal properties from this study can be applied as model parameters to size an appropriate storage container for TES applications. The future model will serve as a predictive tool for determining optimum particle diameter and volume fraction to maximize energy stored and extracted over a given period of time

Safety and satisfaction of patients with nurse’s care in the perioperative

Objetivo: investigar a segurança e a satisfação de pacientes e sua relação com os cuidados dos enfermeiros no perioperatório. Método: estudo multinível, transversal, correlacional, realizado com 105 enfermeiros da área cirúrgica e 150 pacientes operados em um hospital terciário espanhol. Para os enfermeiros foram coletadas as variáveis sociodemográficas, a percepção do ambiente de trabalho, o desgaste profissional e a satisfação no trabalho. Para os pacientes, a segurança de eventos adversos e nível de satisfação, por meio de registros e questionários. Utilizou-se análise multinível, univariada e multivariada. Resultados: satisfação no trabalho, compromisso profissional e participação em questões hospitalares foram preditores negativos para eventos adversos relacionados ao paciente, enquanto o cuidado do enfermeiro no pós-operatório foi um preditor positivo. Conclusão: observa-se aumento dos eventos adversos quando os enfermeiros têm insatisfação no trabalho, menor compromisso profissional e baixa disponibilidade para participar nos assuntos de sua unidade. Por outro lado, os eventos adversos diminuem quando os enfermeiros realizam os cuidados no pós-operatório. A satisfação foi boa e não houve associação com as características do cuidado dos enfermeiros. Recomenda-se melhorar esses preditores para aumentar a segurança de pacientes cirúrgicos.Objetivo: investigar la seguridad y la satisfacción de los pacientes y su relación con el cuidado de los enfermeros en el perioperatorio. Método: estudio multinivel, transversal, correlacional, realizado con 105 enfermeros del área quirúrgica y 150 pacientes operados en un hospital terciario español. Para los enfermeros fueron recolectadas las variables sociodemográficas, la percepción del ambiente de trabajo, el desgaste profesional y la satisfacción en el trabajo. Para los pacientes, la seguridad de eventos adversos y el nivel de satisfacción, mediante la aplicación de cuestionarios. Se utilizó análisis univariante y multivariante. Resultados: satisfacción en el trabajo, compromiso profesional y participación en cuestiones hospitalarias fueron predictores negativos para eventos adversos relacionados al paciente, mientras que el cuidado del enfermero en el postoperatorio fue un predictor positivo. Conclusión: se observa aumento de los eventos adversos cuando los enfermeros tienen insatisfacción en el trabajo, menor compromiso profesional y baja disponibilidad para participar en los asuntos de su unidad. Por otro lado, los eventos adversos disminuyen cuando los enfermeros realizan los cuidados en el postoperatorio. La satisfacción fue buena y no hubo asociación con las características de la atención de los enfermeros. Se recomienda mejorar estos predictores para aumentar la seguridad de los pacientes quirúrgicos.Objective: to investigate the safety and satisfaction of patients and their relationship with nurse’s care in the perioperative period. Method: cross-sectional, multi-level, correlational study with 105 nurses in the surgical area and 150 patients operated in a Spanish tertiary hospital. For the nurses the sociodemographic variables, the perception of the work environment, the professional burnout and the satisfaction in the work were collected. For patients, the safety of adverse events and level of satisfaction, through the application of questionnaires. Univariate and multivariate analysis were used. Results: job satisfaction, professional commitment, and participation in hospital issues were negative predictors for adverse events related to the patient, while postoperative nurse care was a positive predictor. Conclusion: there is an increase in adverse events when nurses are dissatisfied at work, less professional commitment and low availability to participate in the subjects of their unit. On the other hand, adverse events decrease when nurses perform the care in the postoperative period. Satisfaction was good and there was no association with the characteristics of nurses’ attention. It is recommended to improve these predictors to increase the safety of surgical patients

Safety and satisfaction of patients with nurse’s care in the perioperative

Objetivo: investigar a segurança e a satisfação de pacientes e sua relação com os cuidados dos enfermeiros no perioperatório. Método: estudo multinível, transversal, correlacional, realizado com 105 enfermeiros da área cirúrgica e 150 pacientes operados em um hospital terciário espanhol. Para os enfermeiros foram coletadas as variáveis sociodemográficas, a percepção do ambiente de trabalho, o desgaste profissional e a satisfação no trabalho. Para os pacientes, a segurança de eventos adversos e nível de satisfação, por meio de registros e questionários. Utilizou-se análise multinível, univariada e multivariada. Resultados: satisfação no trabalho, compromisso profissional e participação em questões hospitalares foram preditores negativos para eventos adversos relacionados ao paciente, enquanto o cuidado do enfermeiro no pós-operatório foi um preditor positivo. Conclusão: observa-se aumento dos eventos adversos quando os enfermeiros têm insatisfação no trabalho, menor compromisso profissional e baixa disponibilidade para participar nos assuntos de sua unidade. Por outro lado, os eventos adversos diminuem quando os enfermeiros realizam os cuidados no pós-operatório. A satisfação foi boa e não houve associação com as características do cuidado dos enfermeiros. Recomenda-se melhorar esses preditores para aumentar a segurança de pacientes cirúrgicos.Objetivo: investigar la seguridad y la satisfacción de los pacientes y su relación con el cuidado de los enfermeros en el perioperatorio. Método: estudio multinivel, transversal, correlacional, realizado con 105 enfermeros del área quirúrgica y 150 pacientes operados en un hospital terciario español. Para los enfermeros fueron recolectadas las variables sociodemográficas, la percepción del ambiente de trabajo, el desgaste profesional y la satisfacción en el trabajo. Para los pacientes, la seguridad de eventos adversos y el nivel de satisfacción, mediante la aplicación de cuestionarios. Se utilizó análisis univariante y multivariante. Resultados: satisfacción en el trabajo, compromiso profesional y participación en cuestiones hospitalarias fueron predictores negativos para eventos adversos relacionados al paciente, mientras que el cuidado del enfermero en el postoperatorio fue un predictor positivo. Conclusión: se observa aumento de los eventos adversos cuando los enfermeros tienen insatisfacción en el trabajo, menor compromiso profesional y baja disponibilidad para participar en los asuntos de su unidad. Por otro lado, los eventos adversos disminuyen cuando los enfermeros realizan los cuidados en el postoperatorio. La satisfacción fue buena y no hubo asociación con las características de la atención de los enfermeros. Se recomienda mejorar estos predictores para aumentar la seguridad de los pacientes quirúrgicos.Objective: to investigate the safety and satisfaction of patients and their relationship with nurse’s care in the perioperative period. Method: cross-sectional, multi-level, correlational study with 105 nurses in the surgical area and 150 patients operated in a Spanish tertiary hospital. For the nurses the sociodemographic variables, the perception of the work environment, the professional burnout and the satisfaction in the work were collected. For patients, the safety of adverse events and level of satisfaction, through the application of questionnaires. Univariate and multivariate analysis were used. Results: job satisfaction, professional commitment, and participation in hospital issues were negative predictors for adverse events related to the patient, while postoperative nurse care was a positive predictor. Conclusion: there is an increase in adverse events when nurses are dissatisfied at work, less professional commitment and low availability to participate in the subjects of their unit. On the other hand, adverse events decrease when nurses perform the care in the postoperative period. Satisfaction was good and there was no association with the characteristics of nurses’ attention. It is recommended to improve these predictors to increase the safety of surgical patients

Valor literario-pedagógico de la fábula. Estudio comparativo de Leonardo da Vinci y Félix María Samaniego.

Sin resume

Trenetako ikusmen artifizialeko sistemaren hardware bidezko azelerazioa

Trenen automatizazioan beharrezkoa da ingurunearen informazioa hautemateko gai izango den sistema bat edukitzea: PER edo PERception modulua. Sentsoreetako datuak irakurri, prozesatu eta erabakiak hartzen dituen sistemari igortzeaz arduratzen den modulu horrek Polaris izena hartzen du CAF Signalling enpresan, eta ikusmen artifizialean oinarritzen du bere jarduna. Informazio-fluxu hori denbora errealeko aplikazioa da, gertaera eman denetik sistemak horren berri izan arte igarotako denbora kritikoa baita. Ziklo hori murrizteko, edo ziklo berean kalkulu gehiago egiteko (sentsore gehiagoren datuak prozesatzeko, adibidez), prozesuaren atalak optimizatu behar dira. Proiektu honen helburua Polaris-eko objektuen detekzioko zatia optimizatzea da. Horretarako, erabiltzen diren hardware azeleragailuei eta une honetan PER sistemak darabilen Nvidia Jetson Xavier AGX gailuaren ezaugarriei buruzko ikerketa lan bat egin da, hasteko. Ateratako ondorioetan ikusi da gailu honetan egokiena Nvidiaren sare neuronalak optimizatzeko TensorRT liburutegia erabiltzea dela. Beraz, ondoren, CNN sareak optimizatu eta inferentzia gauzatzeko prozesua lan honetarako bereziki sortutako Casio azpimoduluan bildu da, Polaris-en integratu ahal izateko. Etorkizunean bestelako modeloetara hedatzea aurreikusi arren, momentuz YOLOv4 sarea optimizatu da, TensorRT-k eskaintzen duena beharrezko metodo eta CUDA kernelekin osatuz. Prozesu horri esker, detekzioetan antzeko kalitatea mantenduz errendimendua nabarmen hobetu da: inferentzia-denbora edo latentzia erdira murrizu da; beste hitzetan, emaria edo throughputa bikoiztea lortu da

Manning, J.G. The last Pharaos. Egypt under the Ptolemies, 305-30 BC. Princeton (New Jersey), Oxford: Princeton University Press, 2010

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Las oligarquías urbanas de Pamplona y Tudela en 1366. Dos comportamientos diversoJ ante el fisco real navarro

The Libro de fuegos de 1366 (The Book on Habits and Customs of 1366) is the only text that allows us to study, in details, the way in which the inhabitants of the two main cities of the realm, Pamplona and Tudela, used to contribute in the tax system. Among a very reduced series of fiscal censuses in Navarra during the Middle Ages, this book is quite unique because it registers both the name of the heads of family and the quota asigned to each one. The meticulous revision of the original manuscript, which transcription by J. Carrasco in 1973 helped us to study it in detail -as well as complementary information obtained through other sources allows us to find surprising conclu­sions. One of them is that the 33 families of the high bourgeoisie in Pamplona paid, on an average, scarcely 3 florins while the average of the 68 most famous lineages in Tudela contributed with 8 florins. We do not know the reasons for this important difference, Tudela's families exceed largely the average of 2,5 florins per family, foreseen for the realm as a whole. We also ignore the reasons why, in Tudela, the four levels of quota (1, 2, 3 and 4 florins) established far that peculiar year by royal norms are not respected.Parmi la mince série de dénombrements fiscaux en Navarre au Moyen Age, le Libro de fuegos de 1366 (Livre des Us et Coutumes de 1366), par le seul fait qu'il enregistre aussi bien les noms des têtes de famille que la quotité qui était assignée à chacune d'elles, est l'unique texte qui nous permet d'étudier, avec quelques détails, la façon done contribuèrent, à cette époque, les habitants des deux principales villes du royaume: Pamplona et Tudela. La minutieuse révision du manuscrit original -que la transcription, publiée par J. Carrasco en 1973, nous a permis d'étudier à fond- en même temps que l'informa­tion complémentaire obtenue à partir d'autres sources, nous permet de déboucher sur de surprenantes conclusions: les 33 familles de la haute bourgeoisie de Pamplona payèrent une moyenne de 3 florins à peine, tandis que la moyenne des 68 noms les plus connus de Tudela intervinrent, eux, pour 8 florins. Nous ne savons pas les raisons de cette claironnante différence, les familles de Tudela dépassant largement la moyenne -prévue pour l’ensemble du royaume- de 2,5 florins par famille, pas plus que nous ne connaissons les raisons pour lesquelles, à Tudela, on ne respecta pas les quatre niveaux de cotisation (quotité) (1, 2, 3 et 4 florins) que les normes royales avaient établis cette année-la