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Imagen de apoyo de  Generative Design of Modular/Industrial Architectural System = Diseño Generativo de Sistema Arquitectónico Modular/Industrial

Generative Design of Modular/Industrial Architectural System = Diseño Generativo de Sistema Arquitectónico Modular/Industrial

Por: Wilson Giovanny Zárate Granados | Fecha: 2023

Abstract: One of the recurring problems in the construction industry is its recognised lack of productivity due to different factors, among which could be highlighted the fragmentation of the information flow between the different phases of the project life cycle and the difficulty in communication between the different stakeholders. To address this, the industry has reacted through the use of prefabrication and the implementation of new technologies such as Building Information Modelling. The aim is to improve both productivity, through mass customisation, and the flow of information between phases and stakeholders in the projects, through the use of software and platforms, which also give the possibility of automation with processes such as Generative Design. The dissertation investigates the use of these technologies in the area of prefabrication in construction, focusing on the current implementation of configurators and the associated automation that could be derived from their use for the development of projects. Taking a hybrid prefabrication system (wood and concrete) currently used by CASAIS company as a case study, the research seeks to develop a framework that exploits the modular characteristics of these systems, especially in the design phase. It is in this phase where it is possible to take advantage of the limited number of parameters of the prefabricated elements in automating the generation of design proposals and in obtaining information related to KPIs, which would, in turn, allow a more objective feasibility analysis during this first phase of the project. The indicated solution is, firstly, the proposal of a methodology to develop a configurator applied to the case study, which uses tools and/or platforms, that are currently present in the market related to BIM and the construction industry. Then the dissertation continues with the specific development of the section of the methodology corresponding to the generation of the computational model, and for this purpose visual programming is used, taking as initial information the relevant parameters and data to be obtained that are typical of the prefabrication system studied. The research seeks to make a contribution to the current progress in terms of productivity and information flow that has been developed in the construction industry with the implementation of prefabrication and BIM. With the use of configurators, associated with these new technologies, an incursion into automation methods is proposed, especially in the project gestation phases through Generative Design. Thus, by making use of the mass customisation possibilities offered by prefabrication systems and the integration of nonprofessional agents, (taking advantage of the ease of use of the configurators), a more integrated design process and a more objective decision-making process can be achieved, since it is based on more accurate data related to the feasibility of the projects.
Fuente: Biblioteca Virtual Banco de la República Formatos de contenido: Tesis
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Generative Design of Modular/Industrial Architectural System = Diseño Generativo de Sistema Arquitectónico Modular/Industrial

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Imagen de apoyo de  CO2 and H2 Activation on Zinc-Doped Copper Clusters = Activación de CO2 e Hidrógeno en Clusters de Cobre Dopados con Zinc

CO2 and H2 Activation on Zinc-Doped Copper Clusters = Activación de CO2 e Hidrógeno en Clusters de Cobre Dopados con Zinc

Por: Bárbara; Nyulászi Zamora Yusti | Fecha: 2023

Abstract: Here we systematically investigate the CO2 and H2 activation and dissociation on small CunZn{0/+} (n=3-6) clusters using Density Functional Theory. We show that Cu6Zn is a superatom, displaying an increased HOMO-LUMO gap and is inert towards CO2 or H2 activation or dissociation. While other neutral clusters weakly activate CO2, the cationic clusters preferentially bind the CO2 in monodentate nonactivated way. Notably, Cu4Zn allows for the dissociation of activated CO2, whereas larger clusters destabilize all activated CO2 binding modes. Conversely, H2 dissociation is favored on all clusters examined, except for Cu6Zn. Cu3Zn+ and Cu4Zn, favor the formation of formate through the H2 dissociation pathway rather than CO2 dissociation. These findings suggest the potential of these clusters as synthetic targets and underscore their significance in the realm of CO2 hydrogenation. Resumen: En este estudio, llevamos a cabo una investigación sistemática sobre la activación y disociación del CO2 y H2 en pequeños clusters de CunZn{0/+} (n=3-6) utilizando la Teoría del Funcional de la Densidad. Demostramos que Cu6Zn es un superátomo, exhibiendo un aumento en la brecha HOMO-LUMO y es inerte ante la activación y disociación tanto del CO2 como del H2. Mientras que otros clusters neutros activan débilmente el CO2, los clusters catiónicos tienden a enlazar preferentemente el CO2 de manera monodentada no activada. Notablemente, Cu4Zn permite la disociación del CO2 activado, mientras que clusters más grandes desestabilizan todos los modos de enlace activados del CO2. Por otro lado, la disociación del H2 es favorecida en todos los clusters examinados, excepto para Cu6Zn. Cu3Zn+ y Cu4Zn favorecen la formación del ion formato a través de la ruta de disociación del H2 en lugar de la disociación del CO2. Estos hallazgos sugieren el potencial de estos clusters como objetivos sintéticos y subrayan su importancia en el ámbito de la hidrogenación del CO2.
Fuente: Biblioteca Virtual Banco de la República Formatos de contenido: Artículos
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CO2 and H2 Activation on Zinc-Doped Copper Clusters = Activación de CO2 e Hidrógeno en Clusters de Cobre Dopados con Zinc

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Imagen de apoyo de  Assessment of Efficacy and Mechanism of Resistance to Soil-Applied PPO Inhibitors in Amaranthus palmeri = Evaluación de la eficacia y el mecanismo de resistencia a los inhibidores de PPO aplicados al suelo en Amaranthus palmeri

Assessment of Efficacy and Mechanism of Resistance to Soil-Applied PPO Inhibitors in Amaranthus palmeri = Evaluación de la eficacia y el mecanismo de resistencia a los inhibidores de PPO aplicados al suelo en Amaranthus palmeri

Por: Gulab; Porri Rangani | Fecha: 2023

Abstract: Resistance to protoporphyrinogen oxidase (PPO) inhibitors in Palmer amaranth is a majorconcern, given the high selection pressure and increasing number of populations with reducedsensitivity to PPO herbicides in the US. We evaluated the effect of five soil-applied herbicides onPalmer amaranth (Amaranthus palmeriS. Wats.) populations collected in 2014 and 2015 in Arkansas,USA. Soil-applied saflufenacil, sulfentrazone, and flumioxazin reduced the seedling emergence 91–100%; however, fomesafen and oxyfluorfen showed reduced (63–90%) efficacy on some populations.Target-site mutation (TSM) is the major mechanism of resistance to PPO herbicides; therefore, sixpopulations showing resistance to soil-applied fomesafen were selected for molecular investigations.A total of 81 survivors were genotyped for all known resistance-conferring mutations. A total of 64%and 36% survivors had single and double TSMs, respectively, with 69% of plants carrying TSM inboth alleles ofPPO2. Three survivors from two populations showed an additional copy ofPPO2,whereas all other survivors had one copy. Expression analysis showed 3- to 6-fold upregulation ofPPO2in all plants from resistant populations tested. Transgenic overexpression of WT-ApPPO2anddG210-Apppo2inA. thalianaconfirmed the reduced sensitivity to soil-applied fomesafen compared tothe wild type. Collectively, PPO inhibitors applied pre-emergence are still effective in controllingpopulations resistant to foliar-applied PPO herbicides. Mechanically, elevated expression of resistantPPO2, alongside functional TSM, contribute to reduced sensitivity to soilapplied fomesafen.
Fuente: Biblioteca Virtual Banco de la República Formatos de contenido: Artículos
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Assessment of Efficacy and Mechanism of Resistance to Soil-Applied PPO Inhibitors in Amaranthus palmeri = Evaluación de la eficacia y el mecanismo de resistencia a los inhibidores de PPO aplicados al suelo en Amaranthus palmeri

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Imagen de apoyo de  The erasure of topological defects and the saturation phenomenon

The erasure of topological defects and the saturation phenomenon

Por: Juan Sebastián Valbuena Bermúdez | Fecha: 2023

Abstract: When lower-dimensional self-sustained objects encounter higher-dimensional ones, they can be dissolved and absorbed. We delve into this intriguing erasure phenomenon resulting from topological defects’ interaction. This general phenomenon has significant implications in cosmology and fundamental physics, which we discuss in the first part of the thesis. We start with the erasure of onedimensional objects. One key finding is that vortices or strings of all kinds, such as cosmic strings, QCD flux tubes, or fundamental strings, undergo erasure when encountering defects like domain walls, solitonic structures, or D-branes that deconfine their fluxes. Consequently, a new mechanism of cosmic string break-up emerges. We explain the erasure phenomenon by the loss of coherence in the annihilation process. Additionally, for the case of point-like objects immersed in three-dimensional objects, we explore the interactions between magnetic monopoles and domain walls formed by the same order parameter within an SU(2) gauge theory. As previously suggested, a collision between monopoles and a domain wall leads to their erasure. The monopoles unwind and spread their magnetic charge over the wall, with the erasure process consistently occurring due to the loss of coherence in the collision and the entropy suppression on the recreation of a monopole. This erasure phenomenon has significant cosmological implications, particularly in post-inflationary phase transitions. Furthermore, it sheds light on the nature of gauge theories with coexisting phases, such as confining and Higgs phases. The erasure phenomenon has significant imprints in cosmology and astrophysics as well. In particular, a new mechanism of cosmic string break-up emerges. Moreover, the monopole erasure may serve as a solution to the cosmological monopole problem. In another investigation of interactions of topological defects, we examine the annihilation of a pair of ’t Hooft-Polyakov monopoles confined by a string. We focus on scenarios where the scales of monopoles and strings are comparable. The emitted GW spectrum agrees with previous calculations for wavelengths longer than the system width and before the collision. However, in head-on collisions, the monopoles are never re-created. Instead, the system decays into waves of Higgs and gauge fields, and the recreation of a monopole pair becomes highly improbable due to the loss of coherence during the annihilation process. This behavior is expected to be analogous in systems involving heavy quarks connected by a QCD string. Thus, in a similar regime, the string does not re-stretch after the initial collapse, but the system hadronizes and decays into numerous mesons and glueballs. In the second part of the thesis, we changed our subject of study to another self-sustained objects. These objects attain the maximal entropy permitted by unitarity. They are called saturons, as they saturate unitarity and entropy bounds. Interestingly enough, they share many properties with black holes, for which they are considered exceptional. For instance, the time evolution and information-processing properties of BHs are also found in saturons. Thus, we suggest a “Black hole-Saturon” correspondence. Our work confirms this connection within a renormalizable SU(N) invariant theory. The theory’s spectrum contains a tower of non-topological defects of the Q-ball type, or vacuum bubbles, representing bound states of SU(N) Goldstones. Surprisingly, despite the absence of gravity, these saturated bound states exhibit striking similarities to BHs, displaying an information horizon, an entropy governed by the Bekenstein-Hawking formula, thermal evaporation at a rate corresponding to their inverse radius, and an information retrieval time equivalent to Page’s time. The BH-Saturon correspondence has profound implications for BH physics and saturated systems, both in fundamental theory and observational aspects.
Fuente: Biblioteca Virtual Banco de la República Formatos de contenido: Tesis
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Imagen de apoyo de  Confinement Slingshot and Gravitational Waves

Confinement Slingshot and Gravitational Waves

Por: Maximilian; Dvali Bachmaier | Fecha: 2023

Abstract: In this paper, we introduce and numerically simulate a quantum field theoretical phenomenon called the gauge ``slingshot"" effect and study its production of gravitational waves. The effect occurs when a source, such as a magnetic monopole or a quark, crosses the boundary between the Coulomb and confining phases. The corresponding gauge field of the source, either electric or magnetic, gets confined into a flux tube stretching in the form of a string (cosmic or a QCD type) that attaches the source to the domain wall, separating the two phases. The string tension accelerates the source towards the wall as sort of a slingshot. The slingshot phenomenon is also exhibited by various sources of other co-dimensionality, such as cosmic strings confined by domain walls or vortices confined by Z_2 strings. Apart from the field-theoretic value, the slingshot effect has important cosmological implications, as it provides a distinct source for gravitational waves. The effect is expected to be generic in various standard model extensions, such as grand unification.
Fuente: Biblioteca Virtual Banco de la República Formatos de contenido: Artículos
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Imagen de apoyo de  Radiation emission during the erasure of magnetic monopoles

Radiation emission during the erasure of magnetic monopoles

Por: Maximilian; Dvali Bachmaier | Fecha: 2023

Abstract: We study the interactions between ’t Hooft-Polyakov magnetic monopoles and the domain walls formed by the same order parameter within an SU(2) gauge theory. We observe that the collision leads to the erasure of the magnetic monopoles, as suggested by Dvali et al. [Phys. Rev. Lett. 80, 2281 (1998)]. The domain wall represents a layer of vacuum with un-Higgsed SU(2) gauge symmetry. When the monopole enters the wall, it unwinds, and the magnetic charge spreads over the wall. We perform numerical simulations of the collision process and, in particular, analyze the angular distribution of the emitted electromagnetic radiation. As in the previous studies, we observe that erasure always occurs. Although not forbidden by any conservation laws, the monopole never passes through the wall. This is explained by entropy suppression. The erasure phenomenon has important implications for cosmology, as it sheds a very different light on the monopole abundance in postinflationary phase transitions and provides potentially observable imprints in the form of electromagnetic and gravitational radiation. The phenomenon also sheds light on fundamental aspects of gauge theories with coexisting phases, such as confining and Higgs phases.
Fuente: Biblioteca Virtual Banco de la República Formatos de contenido: Artículos
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Radiation emission during the erasure of magnetic monopoles

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Imagen de apoyo de  Mosquerías: Relatos supersticiosos, verdades a oídos

Mosquerías: Relatos supersticiosos, verdades a oídos

Por: Daianna Sierra Camacho | Fecha: 2023

Resumen: Este trabajo final de máster presenta el proceso y los resultados del proyecto de investigación - creación artística Mosquerías: Relatos supersticiosos, verdades a oídos, realizado en el marco de la maestría de producción e investigación artística en la Universidad de Barcelona entre 2022 y 2023. A través de esta investigación indagué de forma crítica, estética y antropológica la construcción de la realidad imaginada y de lo que denomino «verdad a oídos», tomando como marco de análisis relatos supersticiosos acerca de cuerpos aparecidos, de los que surgen elementos a explorar. Para ello presenté postulados teóricos y antecedentes artísticos, que han servido como fundamento para la producción y creación de la obra artística que he desarrollado. Expongo los resultados del proceso, dando paso a cinco piezas que he producido a partir de la experiencia con el barro y con la materia sonora. En estas se interpretan narrativas visuales y sonoras, que interactúan entre sí y en el espacio, y que proponen al espectador experimentar de una manera diferente y descentralizada historias comunes supersticiosas acerca de los cuerpos que se aparecen y que se convierten en constructo de la realidad. Un constructo que se genera a partir de imaginarios colectivos, que toma forma a través de la oralidad y la organicidad que surge a partir de los relatos acerca del cuerpo.
Fuente: Biblioteca Virtual Banco de la República Formatos de contenido: Tesis
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Mosquerías: Relatos supersticiosos, verdades a oídos

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Imagen de apoyo de  Dynamics of confined monopoles and similarities with confined quarks

Dynamics of confined monopoles and similarities with confined quarks

Por: Gia; Valbuena Bermúdez Dvali | Fecha: 2023

Abstract: In this work, we study the annihilation of a pair of ‘t Hooft-Polyakov monopoles due to confinement by a string. We analyze the regime in which the scales of monopoles and strings are comparable. We compute the spectrum of the emitted gravitational waves and find it to agree with the previously calculated pointlike case for wavelengths longer than the system width and before the collision. However, we observe that in a head-on collision, monopoles are never recreated. Correspondingly, not even once the string oscillates. Instead, the system decays into waves of Higgs and gauge fields. We explain this phenomenon by the loss of coherence in the annihilation process. Due to this, the entropy suppression makes the recreation of a monopole pair highly improbable. We argue that in a similar regime, analogous behavior is expected for the heavy quarks connected by a QCD string. There too, instead of restretching a long string after the first collapse, the system hadronizes and decays in a high multiplicity of mesons and glueballs. We discuss the implications of our results.
Fuente: Biblioteca Virtual Banco de la República Formatos de contenido: Artículos
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Dynamics of confined monopoles and similarities with confined quarks

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Imagen de apoyo de  Vortex Effects in Merging Black Holes and Saturons

Vortex Effects in Merging Black Holes and Saturons

Por: Gia; Kaikov Dvali | Fecha: 2023

Abstract: Vorticity has recently been suggested to be a property of highly-spinning black holes. The connection between vorticity and limiting spin represents a universal feature shared by objects of maximal microstate entropy, so-called saturons. Using QQ-ball-like saturons as a laboratory for black holes, we study the collision of two such objects and find that vorticity can have a large impact on the emitted radiation as well as on the charge and angular momentum of the final configuration. As black holes belong to the class of saturons, we expect that the formation of vortices can cause similar effects in black hole mergers, leading to macroscopic deviations in gravitational radiation. This could leave unique signatures detectable with upcoming gravitational-wave searches, which can thereby serve as a portal to macroscopic quantum effects in black holes. Note: ancillary video at https://youtu.be/t29WUvZM-io
Fuente: Biblioteca Virtual Banco de la República Formatos de contenido: Artículos
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Vortex Effects in Merging Black Holes and Saturons

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Imagen de apoyo de  Erasure of strings and vortices

Erasure of strings and vortices

Por: Gia; Valbuena Bermúdez Dvali | Fecha: 2023

Abstract: The interaction of defects can lead to a phenomenon of erasure. During this process, a lower-dimensional object gets absorbed and dissolved by a higher-dimensional one. The phenomenon is very general and has a wide range of cosmological and fundamental implications. In particular, all types of strings, such as cosmic strings, QCD flux tubes, or fundamental strings, get erased when encountering a defect, either solitonic or a D-brane that deconfines their fluxes. This leads to a novel mechanism of cosmic string breakup, accompanied by gravitational and electromagnetic radiations. The arguments based on loss of coherence and the entropy count suggest that the erasure probability is very close to one, and strings never make it through the deconfining layer. We confirm this by a numerical simulation of the system, which effectively captures the essence of the phenomenon: a 2+1- dimensional problem of interaction between a Nielsen-Olesen vortex of a U(1) Higgs model and a domain wall, inside which the U(1) gauge group is un-Higgsed, and the magnetic flux is deconfined. In accordance with the entropy argument, in our simulation, the vortex never makes it across the wall.
Fuente: Biblioteca Virtual Banco de la República Formatos de contenido: Artículos
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Erasure of strings and vortices

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