scholarly journals Colapso de la cubierta metálica de un polideportivo; patologías singulares y recurrentes

2012 ◽  
Vol 2 (1) ◽  
pp. 37-45 ◽  
Author(s):  
V. Alegre ◽  
V. Ródenas ◽  
S. Villalba
Keyword(s):  
Stainless Steel ◽  
Knowledge Transmission ◽  
Space Frame ◽  
Steel Bars ◽  
Global Buckling ◽  
Lack Of Knowledge

RESUMENEn ocasiones se producen patologías que aun siendo singulares como es el caso que se presenta, ya se han producido anteriormente, y pese a ello, no se ha sabido transmitir las enseñanzas de esas tipologías de daños, y vuelven a repetirse. Se quiere hacer resaltar que los estudios de daños han de servir para implementar en la normativa los requerimientos necesarios para alejarnos de situaciones de riesgo.Se presenta el colapso de una cubierta espacial metálica con barras de acero inoxidable de sección circular con uniones simplemente ensambladas en sus extremos en una barra que hace las veces de nudo.Palabras clave: Pandeo local y global; cubierta espacial metálica; siniestros; patologías recurrentes.ABSTRACTNon common pathologies can be presented occasionally and recurrently as in this case study. This happens especially because of a lack of knowledge transmission. Most damage studies must serve to prepare standards and documents to avoid risk situations.It is presented the collapse of a space frame roof with circular stainless steel bars with joints of stainless steel which threads the extremes of the space frame bars.Key words: Local and global; buckling space frame roof; disasters; repeated pathology.

Pyrolysis of brown algae (Bifurcaria Bifurcata) in a stainless steel tubular reactor: From a review to a case study

2018 ◽  
Vol 14 (1) ◽  
pp. 31-60 ◽  
Author(s):  
M. Y. Guida ◽  
F. E. Laghchioua ◽  
A. Hannioui
Keyword(s):  
Particle Size ◽  
Stainless Steel ◽  
Flow Rate ◽  
Brown Algae ◽  
Tubular Reactor ◽  
Nitrogen Flow ◽  
Nitrogen Flow Rate ◽  
Bifurcaria Bifurcata ◽  
Bio Oil

This article deals with fast pyrolysis of brown algae, such as Bifurcaria Bifurcata at the range of temperature 300–800 °C in a stainless steel tubular reactor. After a literature review on algae and its importance in renewable sector, a case study was done on pyrolysis of brown algae especially, Bifurcaria Bifurcata. The aim was to experimentally investigate how the temperature, the particle size, the nitrogen flow rate (N2) and the heating rate affect bio-oil, bio-char and gaseous products. These parameters were varied in the ranges of 5–50 °C/min, below 0.2–1 mm and 20–200 mL. min–1, respectively. The maximum bio-oil yield of 41.3wt% was obtained at a pyrolysis temperature of 600 °C, particle size between 0.2–0.5 mm, nitrogen flow rate (N2) of 100 mL. min–1 and heating rate of 5 °C/min. Liquid product obtained under the most suitable and optimal condition was characterized by elemental analysis, 1H-NMR, FT-IR and GC-MS. The analysis of bio-oil showed that bio-oil from Bifurcaria Bifurcata could be a potential source of renewable fuel production and value added chemicals.

scholarly journals The Relation of Test-Related Factors to Software Quality: A Case Study on Apache Systems

2021 ◽  
Vol 26 (2) ◽  
Author(s):  
Fabiano Pecorelli ◽  
Fabio Palomba ◽  
Andrea De Lucia
Keyword(s):  
Software Quality ◽  
Compelling Evidence ◽  
Related Factors ◽  
Code Coverage ◽  
Production Code ◽  
Software Code ◽  
Class Test ◽  
Code Quality ◽  
Lack Of Knowledge

AbstractTesting represents a crucial activity to ensure software quality. Recent studies have shown that test-related factors (e.g., code coverage) can be reliable predictors of software code quality, as measured by post-release defects. While these studies provided initial compelling evidence on the relation between tests and post-release defects, they considered different test-related factors separately: as a consequence, there is still a lack of knowledge of whether these factors are still good predictors when considering all together. In this paper, we propose a comprehensive case study on how test-related factors relate to production code quality in Apache systems. We first investigated how the presence of tests relates to post-release defects; then, we analyzed the role played by the test-related factors previously shown as significantly related to post-release defects. The key findings of the study show that, when controlling for other metrics (e.g., size of the production class), test-related factors have a limited connection to post-release defects.

Bīsotūn and the French Enlightenment

2018 ◽  
Vol 28 (4) ◽  
pp. 583-614
Author(s):  
DANIEL THOMAS POTTS
Keyword(s):  
Knowledge Transmission ◽  
Republic Of Letters ◽  
Western Iran ◽  
The Enlightenment ◽  
French Enlightenment ◽  
Political Service

AbstractThis study examines a little-known case of Enlightenment knowledge transmission centred on the rock-cut monument of Darius I at Bīsotūn in western Iran. It discusses a report on the monument published by the cartographer and historian Jean-Baptiste Bourguignon d'Anville, which originated with the Decalced Carmelite monk Emmanuel de Saint-Albert (born Jean-Claude Ballyet); who transmitted it to Isaac Bellet, a doctor involved in secret negotiations in Constantinople; who in turn sent it to Louis, Duke d'Orléans, in Paris; who passed it on to d'Anville. The collison of scholarly interest, political service and scientific personality offers a fascinating case study of the Enlightenment ‘republic of letters’ in action.

Limitations of Corrosion Resistant Alloy in High CO2 Gas Production Systems: A Case Study

2021 ◽  
Author(s):  
Jorge Rodriguez ◽  
Susana Gómez ◽  
Ngoc Tran Dinh ◽  
Giovanni Ortuño ◽  
Narendra Borole
Keyword(s):  
Heat Transfer ◽  
Fluid Dynamics ◽  
High Pressure ◽  
Stainless Steel ◽  
Carbon Steel ◽  
Material Selection ◽  
Dynamic Modelling ◽  
General Corrosion ◽  
High Co2

Abstract The paper presents the application of a holistic approach to corrosion prediction that overcomes classical pitfalls in corrosion testing and modelling at high pressure, high temperature and high CO2 conditions. Thermodynamic modelling of field and lab conditions allows for more accurate predictions by a novel CO2/H2S general corrosion model validated by laboratory tests. In the proposed workflow, autoclave tests at high pressure and temperature are designed after modeling corrosion in a rigorous thermodynamic framework including fluid-dynamic modelling; the modeled steps include preparation, gas loading and heating of fluid samples at high CO2 concentration, and high flow velocities. An autoclave setup is proposed and validated to simultaneously test different conditions. Corrosion rates are extrapolated to compute service life of the materials and guide material selection. The results from the model and tests extend the application of selected stainless steel grade beyond the threshold conditions calculated by simplistic models and guidelines. Consideration of fugacities and true aqueous compositions allows for accurate thermodynamic representation of field conditions. Computation by rigorous fluid dynamics of shear stress, multiphase flow and heat transfer effects inside completion geometry lead to a proper interpretation of corrosion mechanisms and models to apply. In the case study used to showcase the workflow, conventional stainless steel is validated for most of the tubing. It is observed that some sections of the system in static condition are not exposed to liquid water, allowing for safe use of carbon steel, while as for other critical parts, more noble materials are deemed necessary. Harsh environments pose a challenge to the application of conventional steel materials. The workflow applied to the case study allows accurate representation and application of materials in its application limit region, allowing for safe use of carbon steel or less noble stainless steels in those areas of the completion where corrosion is limited by multiphase fluid-dynamics, heat transfer or the both. The approximation is validated for real case study under high CO2 content, and is considered also valid in the transportation of higher amounts of CO2, for example, in CCUS activities.

scholarly journals Three-Dimensional Assembly Synthesis for Robust Dimensional Integrity Based on Screw Theory

2004 ◽  
Vol 128 (1) ◽  
pp. 243-251 ◽  
Author(s):  
Byungwoo Lee ◽  
Kazuhiro Saitou
Keyword(s):  
Screw Theory ◽  
Three Dimensional ◽  
Proper Part ◽  
Space Frame ◽  
Reverse Sequence ◽  
3D Representation

This paper presents a three-dimensional (3D) extension of our previous work on the synthesis of assemblies whose dimensional integrity is insensitive to the dimensional variations of individual parts. Assuming that assemblies can be built in the reverse sequence of decomposition, the method recursively decomposes a given product geometry into two subassemblies until parts become manufacturable. At each recursion, joints are assigned to the interfaces between two subassemblies to ensure the two criteria for robust dimensional integrity, in-process dimensional adjustability, and proper part constraints. Screw theory is utilized as a unified 3D representation of the two criteria. A case study on an automotive space frame is presented to demonstrate the method.

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