Development of an Experimental Methodology of Boiling Phenomenon in the Evaporator of a Glass Thermosyphon

Author(s):  
Diógenes Oliveira de Souza ◽  
Ramaiana M. Davies ◽  
PAULO HENRIQUE DIAS DOS SANTOS ◽  
Thiago Antonini Alves
1985 ◽  
Vol 30 (9) ◽  
pp. 711-711
Author(s):  
Steven C. Hayes

Author(s):  
Marie-Pascale Chagny ◽  
John A. Naoum

Abstract Over the years, failures induced by an electrostatic discharge (ESD) have become a major concern for semiconductor manufacturers and electronic equipment makers. The ESD events that cause destructive failures have been studied extensively [1, 2]. However, not all ESD events cause permanent damage. Some events lead to recoverable failures that disrupt system functionality only temporarily (e.g. reboot, lockup, and loss of data). These recoverable failures are not as well understood as the ones causing permanent damage and tend to be ignored in the ESD literature [3, 4]. This paper analyzes and characterizes how these recoverable failures affect computer systems. An experimental methodology is developed to characterize the sensitivity of motherboards to ESD by simulating the systemlevel ESD events induced by computer users. The manuscript presents a case study where this methodology was used to evaluate the robustness of desktop computers to ESD. The method helped isolate several weak nets contributing to the failures and identified a design improvement. The result was that the robustness of the systems improved by a factor of 2.


2021 ◽  
Vol 11 (3) ◽  
pp. 1253
Author(s):  
Evaggelos Kaselouris ◽  
Kyriaki Kosma ◽  
Yannis Orphanos ◽  
Alexandros Skoulakis ◽  
Ioannis Fitilis ◽  
...  

A three-dimensional, thermal-structural finite element model, originally developed for the study of laser–solid interactions and the generation and propagation of surface acoustic waves in the macroscopic level, was downscaled for the investigation of the surface roughness influence on pulsed laser–solid interactions. The dimensions of the computational domain were reduced to include the laser-heated area of interest. The initially flat surface was progressively downscaled to model the spatial roughness profile characteristics with increasing geometrical accuracy. Since we focused on the plastic and melting regimes, where structural changes occur in the submicrometer scale, the proposed downscaling approach allowed for their accurate positioning. Additionally, the multiscale simulation results were discussed in relation to experimental findings based on white light interferometry. The combination of this multiscale modeling approach with the experimental methodology presented in this study provides a multilevel scientific tool for an in-depth analysis of the influence of heat parameters on the surface roughness of solid materials and can be further extended to various laser–solid interaction applications.


Religions ◽  
2021 ◽  
Vol 12 (5) ◽  
pp. 357
Author(s):  
Rafael López Cordero ◽  
Francisca Ruiz Garzón ◽  
Lourdes Medina Martínez ◽  
María del Carmen Olmos-Gómez

The current trend of secularization seems to be leading to a gradual withdrawal of religion from public spaces. However, in an increasingly internationalized world, it is becoming more and more important to study the roles of religion and religiosity and their potential in relation to dialogue and social conflicts and tensions. Education is a vital field within which to address this religious issue and create an educational dialogue in order to promote coexistence. By following a quantitative, descriptive, cross-sectional study, based on a quasi-experimental methodology with a social–analytical character, our aim is to assess the existing connections between religion, interrelation and opinion in Spanish children and adolescents. Special attention is paid to the interaction between age and beliefs. We carried out our study with the use of a questionnaire distributed to eleven secondary schools, with students aged between 11 and 16 years old, in three regions of southern Spain (Andalusia, Ceuta, and Melilla) characterized by high religious diversity and multiculturalism. The multivariate analysis carried out in this study identifies the effects of variance on the influence of age and religion, highlighting the interaction between the two. It is observed that the youngest students are those who express their opinions about religion the least, while those belonging to younger age groups and majority religions are those who express a greater religious coexistence, with Muslims externalizing their religious condition the most.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Rakesh David ◽  
Rhys-Joshua D. Menezes ◽  
Jan De Klerk ◽  
Ian R. Castleden ◽  
Cornelia M. Hooper ◽  
...  

AbstractThe increased diversity and scale of published biological data has to led to a growing appreciation for the applications of machine learning and statistical methodologies to gain new insights. Key to achieving this aim is solving the Relationship Extraction problem which specifies the semantic interaction between two or more biological entities in a published study. Here, we employed two deep neural network natural language processing (NLP) methods, namely: the continuous bag of words (CBOW), and the bi-directional long short-term memory (bi-LSTM). These methods were employed to predict relations between entities that describe protein subcellular localisation in plants. We applied our system to 1700 published Arabidopsis protein subcellular studies from the SUBA manually curated dataset. The system combines pre-processing of full-text articles in a machine-readable format with relevant sentence extraction for downstream NLP analysis. Using the SUBA corpus, the neural network classifier predicted interactions between protein name, subcellular localisation and experimental methodology with an average precision, recall rate, accuracy and F1 scores of 95.1%, 82.8%, 89.3% and 88.4% respectively (n = 30). Comparable scoring metrics were obtained using the CropPAL database as an independent testing dataset that stores protein subcellular localisation in crop species, demonstrating wide applicability of prediction model. We provide a framework for extracting protein functional features from unstructured text in the literature with high accuracy, improving data dissemination and unlocking the potential of big data text analytics for generating new hypotheses.


2021 ◽  
Vol 13 (5) ◽  
pp. 2501
Author(s):  
Valentina Acuña ◽  
Francisca Roldán ◽  
Manuel Tironi ◽  
Leila Juzam

Landslide disaster risks increase worldwide, particularly in urban areas. To design and implement more effective and democratic risk reduction programs, calls for transdisciplinary approaches have recently increased. However, little attention has been paid to the actual articulation of transdisciplinary methods and their associated challenges. To fill this gap, we draw on the case of the 1993 Quebrada de Macul disaster, Chile, to propose what we label as the Geo-Social Model. This experimental methodology aims at integrating recursive interactions between geological and social factors configuring landslide for more robust and inclusive analyses and interventions. It builds upon three analytical blocks or site-specific environments in constant co-determination: (1) The geology and geomorphology of the study area; (2) the built environment, encompassing infrastructural, urban, and planning conditions; and (3) the sociocultural environment, which includes community memory, risk perceptions, and territorial organizing. Our results are summarized in a geo-social map that systematizes the complex interactions between the three environments that facilitated the Quebrada de Macul flow-type landslide. While our results are specific to this event, we argue that the Geo-Social Model can be applied to other territories. In our conclusions, we suggest, first, that landslides in urban contexts are often the result of anthropogenic disruptions of natural balances and systems, often related to the lack of place-sensitive urban planning. Second, that transdisciplinary approaches are critical for sustaining robust and politically effective landslide risk prevention plans. Finally, that inter- and trans-disciplinary approaches to landslide risk prevention need to be integrated into municipal-level planning for a better understanding of—and prevention of—socio-natural hazards.


Materials ◽  
2021 ◽  
Vol 14 (10) ◽  
pp. 2554
Author(s):  
Oleg Naimark ◽  
Vladimir Oborin ◽  
Mikhail Bannikov ◽  
Dmitry Ledon

An experimental methodology was developed for estimating a very high cycle fatigue (VHCF) life of the aluminum alloy AMG-6 subjected to preliminary deformation. The analysis of fatigue damage staging is based on the measurement of elastic modulus decrement according to “in situ” data of nonlinear dynamics of free-end specimen vibrations at the VHCF test. The correlation of fatigue damage staging and fracture surface morphology was studied to establish the scaling properties and kinetic equations for damage localization, “fish-eye” nucleation, and transition to the Paris crack kinetics. These equations, based on empirical parameters related to the structure of the material, allows us to estimate the number of cycles for the nucleation and advance of fatigue crack.


Sensors ◽  
2021 ◽  
Vol 21 (9) ◽  
pp. 2925
Author(s):  
Antonio Mederos-Barrera ◽  
Cristo Jurado-Verdu ◽  
Victor Guerra ◽  
Jose Rabadan ◽  
Rafael Perez-Jimenez

Visible light communications (VLC) technology is emerging as a candidate to meet the demand for interconnected devices’ communications. However, the costs of incorporating specific hardware into end-user devices slow down its market entry. Optical camera communication (OCC) technology paves the way by reusing cameras as receivers. These systems have generally been evaluated under static conditions, in which transmitting sources are recognized using computationally expensive discovery algorithms. In vehicle-to-vehicle networks and wearable devices, tracking algorithms, as proposed in this work, allow one to reduce the time required to locate a moving source and hence the latency of these systems, increasing the data rate by up to 2100%. The proposed receiver architecture combines discovery and tracking algorithms that analyze spatial features of a custom RGB LED transmitter matrix, highlighted in the scene by varying the cameras’ exposure time. By using an anchor LED and changing the intensity of the green LED, the receiver can track the light source with a slow temporal deterioration. Moreover, data bits sent over the red and blue channels do not significantly affect detection, hence transmission occurs uninterrupted. Finally, a novel experimental methodology to evaluate the evolution of the detection’s performance is proposed. With the analysis of the mean and standard deviation of novel K parameters, it is possible to evaluate the detected region-of-interest scale and centrality against the transmitter source’s ideal location.


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