1,067 research outputs found
Which Is the Correct Form of the Popular Name for Our Galaxy: Kumova Slama or Kumovska Slama?
No full textThe paper discusses the formational suffix in the generally accepted Croatian name for our galaxy, the Milky Way. Since there are two forms that occur in normative handbooks: Kumova Slama and Kumovska Slama, the woman author comments the use and the meaning
of the suffixes -ov and -ski for the formation of adjective
A comparison between the SLaMA method and NLFEA for 2D and 3D analyses of masonry structure
No full textEach year, the province of Groningen experiences many induced earthquakes due gas extraction, which has been ongoing since 1963. The earthquakes cause damage to the buildings situated in the Groningen area, and they constitute a potential danger for the safety of the residents. These buildings are typically unreinforced masonry structures which are designed without knowledge of the presence of seismic activity in this area. It is therefore essential develop and use assessment methods that are on one end reliable and accurate, but on the other hand allow to perform a large number of assessments of the vulnerability of the buildings in a short time. In other words, the assessment of all the buildings requires a quick and reliable assessment method. Such an assessment method should offer a strong understanding of the occurring failure mechanism during an earthquake, an acceptable prediction of the ground acceleration at which the collapse of the building may occur (maximum base shear force) and the displacement capacity of unreinforced masonry (URM) building. The NPR9998 recommends four seismic assessment approaches, which differ in complexity and assessment time needed to be performed. The most comprehensive and time-consuming assessment method is the NLTHA (nonlinear time history analysis), which includes both the dynamic and nonlinear effects. In practice, this method is used only in special cases, such as in the case of monumental buildings. A simpler approach is the NLPO (nonlinear pushover) analysis, which is static and considers the nonlinear properties of the structure. An NLPO is less time consuming than an NLTHA, even when the finite element method (FEM) is considered. A more simplified approach is the Simple Lateral Mechanism Analysis (SLaMA). This method is a simplified mechanism-based analytical approach. If the SLaMA method predicts realistically conservative global capacities, it could serve as an effective alternative assessment method for URM buildings, and especially to the NLPO FEM analysis. This study focusses on the comparison between the SLaMA method and the NLPO FEM analysis. Therefore, this study aims to answer the following research question: Could the SLaMA method be a realistically conservative and effective alternative to the NLPO FEM analysis in making a seismic assessment for two-storey unreinforced masonry buildings? In conclusion, the SLaMA method could be a realistically conservative and effective alternative to the NLPO FEM analysis in predicting the maximum base shear force. The displacement capacity predicted using the SLaMA method is validated only for buildings with RC floors. This predicted SLaMA method was realistically conservative compared with the ultimate displacement achieved using the NLPO FEM analysis. The SLaMA method is overall suitable for obtaining a quick understanding of the behaviour of an URM building. However, it requires a proper evaluation of the analyses to identify properly the type and the location of the failure mechanisms. For this reason, this method could be valuable to be applied before using a more complex assessment method.<br/
Extension, refinement and validation of the Simple Lateral Mechanism Analysis (SLaMA) for the seismic assessment of RC structures
No full textIl lavoro in questa tesi riguarda l’estensione, il miglioramento e la validazione della metodologia Simple Lateral Mechanism Analysis (SLaMA) per la valutazione sismica di strutture in CA. Raccomandato nelle linee guida neozelandesi del 2017 relative alla valutazione sismica, NZSEE (2017), SLaMA é un metodo di analisi non-lineare che permette di avere una stima della capacitá di strutture esistenti ed é valido per telai, pareti o sistemi misti telaio/parete. L’idea di base é procedere “dal locale al globale”, partendo dal comportamento di componenti singoli, estendendolo a specifici sottoschemi ed infine giungendo al comportamento globale dell’edificio. É anche possibile considerare gli effetti torsionali in campo non-lineare. Dato che il metodo si basa su ipotesi semplificate, non é necessario ricorrere a modelli numerici e i calcoli possono essere fatti “a mano (i.e. utilizzando un foglio elettronico). La prima parte di questo lavoro di ricerca riguarda i sistemi a telaio nudo, identificando aree di miglioramento della procedura SLaMA esistente e proponendo una procedura estesa e migliorata. Essa é stata validata attraverso la sua applicazione a 40 casi studio ideali e il confronto con i risultati di analisi numeriche raffinate (FEM Pushover). I risultati indicano che la procedura SLaMA modificata permette di identificare accuratamente il meccanismo plastico del telaio, considerando l’effettiva gerarchia delle resistenze dei suoi componenti, e di calcolarne la curva di capacitá con errori accettabili per i suoi parametri più significativi. La parte successiva del lavoro riguarda lo sviluppo di una nuova procedura SLaMA, non presente in NZSEE (2017), per sistemi a telaio tamponato, che rappresentano una cospicua parte del patrimonio edilizio, soprattutto in Europa. La nuova metodologia si basa su una procedura meccanica, proposta in questo lavoro, per disaccoppiare i contributi al taglio alla base relativi al telaio e alle tamponature, per un qualunque valore dello spostamento globale. La procedura di disaggregazione é applicabile a prescindere dalla distribuzione delle tamponature e della curva caratteristica dei puntoni equivalenti. Puó essere inoltre applicata per la post-processione dei risultati di analisi Pushover o Time History di telai tamponati. In analogia a quanto fatto per i telai nudi la procedura SLaMA é stata validata tramite confronto con i risultati di analisi Pushover per 72 casi studio. Sono stati inoltre considerati i sistemi resistenti misti telaio/parete con l’obiettivo di proporre una nuova procedura SLaMA che considerasse esplicitamente l’interazione tra la parte a telaio con quella a parete, includendo il calcolo delle forze da essi scambiate e le eventuali coppie concentrate dovute alla presenza di travi di collegamento. Con la nuova procedura SLaMA é possibile stimare il comportamento dei sistemi duali con grande accuratezza, come dimostrato da una vasta analisi parametrica (SLaMA vs Pushover) che coinvolge 24 casi studio. L’ultima parte del lavoro riguarda la valutazione sismica di un edificio realmente esistito e che ha subito notevoli danni durante la sequenza sismica di Christchurch (Nuova Zelanda) tra il 2010 e il 2011. Lo “score sismico” (capacitá fratto domanda) é stato indipendentemente valutato con diversi metodi di analisi: Lineare Statica, Lineare Dinamica, Non-Lineare Statica (Pushover e SLaMA), Non-Lineare Dinamica. In primis questo confronto incrociato dimostra l’affidabilitá del metodo SLaMA nella valutazione di casi reali complessi. Questo studio dimostra inoltre come le informazioni ottenute utilizzando SLaMA possano essere efficacemente usate per calibrare i parametri fondamentali necessari per gli altri metodi di analisi, o interpretarne i risultati. Sebbene alcuni passi della procedura possono essere calibrati in maniera piú raffinata grazie a sviluppi futuri si puó sicuramente affermare che SLaMA sia un metodo di analisi robusto. Esso é in grado di fornire al tecnico valutatore gli strumenti per comprendere i dettagli del comportamento di un edificio usando esclusivamente calcoli fatti a mano (eventualmente implementati in un semplice foglio elettronico).This dissertation is focused on the extension, refinement and validation of the Simple Lateral Mechanism Analysis (SLaMA) method for the seismic assessment of RC buildings. Suggested in the 2017 New Zealand guidelines for seismic assessment, NZSEE (2017), SLaMA is an analytical non-linear analysis technique that provides a first estimation of the global capacity curve of the primary lateral-resisting systems in RC buildings, including bare frames, cantilever walls and dual wall/frame systems. The basic idea is to progress “from local to global”, extending the local behaviour of the structural members to selected sub-schemes, and finally to the global non-linear response of the building. Inelastic torsional effects are also included. Since simplified assumptions are made, no numerical computer model is needed and hence all the calculations can be performed “by hand” (i.e. implemented in an electronic spreadsheet). The first part of this investigation is related to bare frame Lateral Resisting Systems, with the identification of potential areas of improvement for the existing SLaMA procedure and the proposal of an extended/refined one. The refined procedure for bare frames is validated through the application to a set of 40 ideal case studies and the comparison with refined numerical analyses (FEM Pushover). The results show that the refined SLaMA procedure allows to accurately identify the expected plastic mechanism of the frame, also considering the actual hierarchy of strength of its members, and to properly estimate its non-linear capacity curve with acceptable errors on the most meaningful parameters. The subsequent part of the investigation involves the development of a novel SLaMA method to evaluate the capacity curve of masonry-infilled frames systems, which represent a large portion of the building portfolio, especially in Europe. The incorporation of the contribution of the infills is completely absent in the NZSEE (2017) SLaMA framework. The methodology is based on a proposed mechanically-based procedure to decouple the frame and infills contributions to the overturning moment (and hence base shear) capacity for any value of the global displacement. The decoupling procedure is applicable regardless of the distribution of the infills and of the non-linear Axial load-Axial strain of the equivalent struts. It can be applied to post-process the results of Pushover or Time History analyses of different types of infilled frames (material-wise). Similarly to what done for bare frames, an extensive SLaMA vs numerical Pushover comparison, for a set of 72 ideal case studies, is used to validate the proposed SLaMA procedure. Part of the investigation is dedicated to dual wall/frame system structures, proposing a novel SLaMA procedure in which the coupled behaviour of the frame and wall(s) components is expressly considered, including the calculation of the exchanged forces and the concentrated moment couples due to the possible presence of link beams. By using the new SLaMA procedure it is possible to capture the non-linear behaviour of the dual system with extreme accuracy, as demonstrated with an extensive SLaMA vs numerical Pushover parametric analysis comprising 24 ideal case studies. The last step of the work is the seismic assessment of a real case study building, severely damage in the Christchurch (New Zealand) sequence of earthquakes in 2010-2011. Different analysis techniques are used to independently derive the “seismic score” of the building (capacity over demand), including: Linear Static, Linear Dynamic, Non-Linear Static (numerical Pushover and SLaMA) and Non-Linear Dynamic analyses. Firstly, this demonstrates the reliability of the SLaMA method in assessing real, complex cases by means of a cross-validation. Moreover, and perhaps more importantly, it is deemed that this comparative study demonstrates how the insights gained by using SLaMA can be used to calibrate important parameters needed when adopting other analysis techniques, or interpreting their results. Additional investigations might help in fine-tuning some of its steps but, overall, it is deemed that SLaMA constitutes a robust analysis technique that allows the assessor to really understand the behaviour of an RC building only using hand calculations, possibly implemented in a simple spreadsheet
A Framework and Tool for Knowledge-Based Seismic Risk Assessment of School Buildings: SLaMA-School
No full textWhen dealing with seismic risk assessment at a large scale, the collection of relevant building data is still deemed a challenging task, often leading to limited building knowledge and, consequently, high uncertainties. Therefore, innovative yet standardized frameworks and adaptive tools are needed to support the seismic risk assessment of buildings. Towards this goal, this paper proposes a simplified multi-knowledge seismic assessment methodology involving the analytical-mechanical SLaMA (Simple Lateral Mechanism Analysis) method. An ad-hoc data collection form is first developed to identify the building vulnerabilities by merging and building on existing institutional forms at the international level and integrating new input data. The data are then used to implement the SLaMA-based methodology, at different building knowledge levels, to assess the seismic safety and the economic losses of buildings. The proposed data structure and approach is planned to be included in the “Seismic-Response” module for PELL (Public Energy Living Lab)-School platform, aiming to become a standardized and interoperable database for relevant data of Italian schools and a dashboard for allowing stakeholders to continuously monitor their energetic and static/seismic conditions. The paper discusses the potential and effectiveness of the proposed procedure for large-scale applications and its integration into platforms assessing the energy efficiency of buildings.Structural Design & Mechanic
Rozhovor Britských listů 121. Mám velkou příchylnost k přirozenému životu [Britské listy Interview 121] I have great affinity to natural life
No full textAt the Karlovy Vary International Film Festival, Jan Culik interviews the celebrated Czech film director Bohdan Slama about his five feature films, especially his latest Bába z ledu (Ice Mother, 2017)
Seismic assessment of a RC case study building using the Simple Lateral Mechanism Analysis, SLaMA, method
No full textThe seismic assessment of an existing structure is a complex procedure. In
the
eval-
uation
of
the structural capacity
,
difficulties arise in the definition of the lateral resisting mem-
bers,
in
the estimation of
the
lateral capacity
from component
to
system level
.
T
he
identification
of the local and global mechanism
s
,
depending on the
hierarchy of strength
at subassembly
level, is
a
challenging
task
. Nowadays,
advanced
numerical
analys
i
s
procedures
, implemented
in user
-
friendly commercial software, are commonly adopted in the current practice to over-
come the difficulties in the use of non
-
linear
analyses
.
Ne
vertheless, their accuracy strongly
depends on the ability of the numerical model to capture all the probable failure mechanisms.
To help the user
in the assessment of the probable failure mechanism and to have a first esti-
mation of the building lateral ca
pacity,
the Simple Lateral Mechanism Analysis (SLaMA)
method
has been recently developed and included in the
NZSEE
2016
guidelines. SLaMA is a
simple
and reliable
“by
-
hand”
tool to derive the local and global mechanism of a structural
system and the corresponding capacity curve.
T
his paper
deals with the application of the
SLaMA to
an existing
RC
building severely damaged during the Christchurch earthquake (2011
,
New Zealand
)
.
The lateral capacity of f
our 2D resisting systems
was
assessed following the
SLaMA
method
.
The
results of a refined nonlinear numerical model were used to assess the
accuracy and reliability of
SLaMA.
The good match confirmed that SLaMA can be a useful
and simple
tool to have a first estimation of the building lateral response
. It allows to identify
the main structural weaknesses driving the user to the development of
more refined nonlinear
model
The atomistic modeling of light-harvesting complexes from the physical models to the computational protocol
No full textThe function of light-harvesting complexes is determined by a complex network of dynamic interactions among all the different components: the aggregate of pigments, the protein, and the surrounding environment. Complete and reliable predictions on these types of composite systems can be only achieved with an atomistic description. In the last few decades, there have been important advances in the atomistic modeling of light-harvesting complexes. These advances have involved both the completeness of the physical models and the accuracy and effectiveness of the computational protocols. In this Perspective, we present an overview of the main theoretical and computational breakthroughs attained so far in the field, with particular focus on the important role played by the protein and its dynamics. We then discuss the open problems in their accurate modeling that still need to be addressed. To illustrate an effective computational workflow for the modeling of light harvesting complexes, we take as an example the plant antenna complex CP29 and its H111N mutant. (c) 2022 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/).2022 Author(s)
NEW METHODS REGARDING THE ORGANISATION AND FUNCTIONALITY OF THE BUSINESS ENVIRONMENT IN THE VIRTUAL ECONOMY
No full textGlobalization represents the destiny humankind is drawing near, everybody being affected to a larger or smaller extent by its irreversible mechanism.The business environment relies on the expansion of markets globally. Therefore it is achieved the transivirtual enterprise, virtual society, mobile Web applications
Supstrat kao faktor prinosa u proizvodnji bukovače (Pleurotus ostreatus)
No full textProduction of oyster mushroom has been intensified for the last two decades and it is developing further on. This has been achieved because of its nutritive value, medicinal effects and simple and cheep production. For their production, the substrate is prepared from waste cellulose material from agricultural production, straw, corn stalks, stems of pea and soybean sunflower husks, sawdust, wood shavings, etc. These materials are usually not utilized, often being burnt because of its low value. Due to an increase in the production of oyster mushroom, there is the need to study factors that directly affect its yields. In addition to the genetic potential of the strain concerned, oyster mushroom yields are also directly correlated with the quality of the substrate and the conditions of production. The raw materials must not only have a great capacity for water absorption, it is also important that the elements oyster mushrooms takes from the substrate are in the most favorable form for decomposition. In three years, at the Vegetables Department of the Institute of Field and Vegetable Crops in Novi Sad, several substrates were studied under laboratory conditions in order to determine the most suitable one for strains NS 77, NS 355 and NS 244, in terms of high yield. We studied the following substrates: soybean straw, corn stalks, sunflower stalks, wheat straw 50% + corn stalks 50%, wheat straw 50% + soybean straw 50%, wheat straw 50% + sunflower stalks 50%, and wheat straw as a control.Proizvodnja bukovače je naglo porasla u zadnje dve decenije i dalje je u usponu. Ovo je ostvareno zbog njene hranljive vrednosti, medicinskog efekta i jednostavne i jeftine proizvodnje. Za proizvodnju se koriste supstrati pripremljeni od ostataka celuloznog materijala iz poljoprivredne proizvodnje kao što su slama, stabljike kukuruza, stabljike graška i soje, ljuspice suncokreta, strugotine i dr. Ovaj materijal se obično više ne koristi, već se spaljuje zbog njegove male vrednosti. Zbog povećane proizvodnje potrebno je ispitati faktore koji direktno utiču na prinos. Na prinos bukovače osim genetskog potencijala soja direktno utiče i kvalitet supstrata kao i uslovi proizvodnje. Vrlo je bitno da sirovina osim velikog kapaciteta apsorpcije sadrži i elemente koji su u najpristupačnijem obliku usvajanja iz supstrata (Bugarski i Jovićević, 1993). Tokom tri godine u Zavodu za povrtarstvo Naučnog instituta za ratarstvo i povrtarstvo u Novom Sadu ispitano je nekoliko supstrata u kontrolisanim uslovima u cilju dobijanja najviših prinosa sojeve Pleurotus ostreatus NS 77, Pleurotus ostreatus NS 355 i Pleurotus ostreatus NS 244. Ispitivani su sledeći supstrati: sojina slama stabljike kukuruza, stabljike suncokreta, pšenična slama 50% + sojina slama 50%, pšenična slama 50% + stabljike kukuruza 50%, pšenična slama 50% stabljike suncokreta 50% i pšenična slama kao kontrola
Erratum to: Review of the nutritional benefits and risks related to intense sweeteners
No full textUnfortunately, the original version of this article [1] contained an error. The author’s names were included incorrectly, the surnames were presented before the forename: Bruyère Olivier, Ahmed H. Serge, Atlan Catherine, Belegaud Jacques, Bortolotti Murielle, Canivenc-Lavier Marie-Chantal, Charrière Sybil, Girardet Jean-Philippe, Houdart Sabine, Kalonji Esther, Nadaud Perrine, Rajas Fabienne, Slama Gérard and Margaritis Irène The author list has been corrected in the original article and is also included correctly below: Olivier Bruyère, Serge H. Ahmed, Catherine Atlan, Jacques Belegaud, Murielle Bortolotti, Marie-Chantal Canivenc-Lavier, Sybil Charrière, Jean-Philippe Girardet, Sabine Houdart, Esther Kalonji, Perrine Nadaud, Fabienne Rajas, Gérard Slama, Irène Margaritis.International audienc
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