Herramientas paramétricas como una base constructiva de una arquitectura efímera pasado - presente - futuro

El trabajo de estudio que se expone a continuación explora el uso de las herramientas paramétricas en arquitectura a través de una investigación teórica sobre las exposiciones que se expusieron a lo largo de la historia, desde el pasado al presente y hacia el futuro. Con la idea de analizar pabellones efímeros paramétricos, se recorre desde la definición entre la paramétrica y lo efímero, explorando los años de entrada de las nuevas herramientas y, los inicios de una arquitectura efímera, pasando de la idea de refugio, alojamiento temporal, a generar más posibilidades de espacios, como son los espacios de mercado y, de estos espacios hacia lo que tenemos hoy en día, las exposiciones. Partiendo de la primera exposición mundial más reconocida del 1851, con la división de diferentes etapas, se seleccionan las exposiciones más influenciadas que tuvieron lugar a lo largo de los años hasta llegar a la última exposición del 2020 en Dubái. Se plantea también la búsqueda de cómo se habían enfrentado los arquitectos de cada época a construir algo efímero, temporal. Que tipo de herramientas se usa para el diseño y cómo se materializa. Y para alcanzar este objetivo se plantea mediante un análisi y comparación de 3 de las obras más emblemáticas con características formales y de función similares de diferentes etapas de exposición: El palacio de trabajo, Expo Roof y el pabellón Sostenibilidad. Finalmente pudiendo Llegar a conclusiones de la evolución del mismo, como con las nuevas herramientas se ha conseguido una mejora en un ámbito de la arquitectura y, en un futuro próximo quizás se pueda aplicar en más ámbitos de la arquitectura, no sólo para las exposiciones

Effective and efficient midlevel visual elements-oriented land-use classification using VHR remote sensing images

Land-use classification using remote sensing images covers a wide range of applications. With more detailed spatial and textural information provided in very high resolution (VHR) remote sensing images, a greater range of objects and spatial patterns can be observed than ever before. This offers us a new opportunity for advancing the performance of land-use classification. In this paper, we first introduce an effective midlevel visual elements-oriented land-use classification method based on “partlets,” which are a library of pretrained part detectors used for midlevel visual elements discovery. Taking advantage of midlevel visual elements rather than low-level image features, a partlets-based method represents images by computing their responses to a large number of part detectors. As the number of part detectors grows, a main obstacle to the broader application of this method is its computational cost. To address this problem, we next propose a novel framework to train coarse-to-fine shared intermediate representations, which are termed “sparselets,” from a large number of pretrained part detectors. This is achieved by building a single-hidden-layer autoencoder and a single-hidden-layer neural network with an L0-norm sparsity constraint, respectively. Comprehensive evaluations on a publicly available 21-class VHR land-use data set and comparisons with state-of-the-art approaches demonstrate the effectiveness and superiority of this paper

Transfer of spin to orbital angular momentum in the Bethe-Heitler process

According to the conservation of angular momentum, when a plane-wave polarized photon splits into a pair of electron-positron under the influence of the Coulomb field, the spin angular momentum (SAM) of the photon is converted into the angular momentum of the leptons. We investigate this process (the Bethe-Heitler process) by describing the final electron and positron with twisted states and find that the SAM of the incident photon is not only converted into SAM of the produced pair, but also into their orbital angular momentum (OAM), which has not been considered previously. The average OAM gained by the leptons surpasses the average SAM, while their orientations coincide. Both properties depend on the energy and open angle of the emitted leptons. The demonstrated spin-orbit transfer shown in the Bethe-Heitler process may exist in a large group of QED scattering processes

Navigating Discrete Difference Equation Governed WMR by Virtual Linear Leader Guided HMPC

In this paper, we revisit model predictive control (MPC) for the classical wheeled mobile robot (WMR) navigation problem. We prove that the reachable set based hierarchical MPC (HMPC), a state-of-the-art MPC, cannot handle WMR navigation in theory due to the non-existence of non-trivial linear system with an under-approximate reachable set of WMR. Nevertheless, we propose a virtual linear leader guided MPC (VLL-MPC) to enable HMPC structure. Different from current HMPCs, we use a virtual linear system with an under-approximate path set rather than the traditional trace set to guide the WMR. We provide a valid construction of the virtual linear leader. We prove the stability of VLL-MPC, and discuss its complexity. In the experiment, we demonstrate the advantage of VLL-MPC empirically by comparing it with NMPC, LMPC and anytime RRT* in several scenarios

From offline toward real-time: A hybrid systems model checking and CPS co-design approach for Medical Device Plug-andPlay (MDPnP

Abstract—Hybrid systems model checking is a great success in guaranteeing the safety of computerized control cyber-physical systems (CPS). However, when applying hybrid systems model checking to Medical Device Plug-and-Play (MDPnP) CPS, we encounter two challenges due to the complexity of human body: i) there are no good offline differential equation based models for many human body parameters; ii) the complexity of human body can result in many variables, complicating the system model. In an attempt to address the challenges, we propose to alter the traditional approach of offline hybrid systems model checking of time-unbounded (i.e., infinite-horizon, a.k.a., long-run) future behavior to online hybrid systems model checking of time-bounded (i.e., finite-horizon, a.k.a., short-run) future behavior. According to this proposal, online model checking runs as a real-time task to prevent faults. To meet the real-time requirements, certain design patterns must be followed, which brings up the co-design issue. We propose two sets of system co-design patterns for hard real-time and soft real-time respectively. To evaluate our proposals, a case study on laser tracheotomy MDPnP is carried out. The study shows the necessity of online model checking. Furthermore, test results based on real-world human subject trace show the feasibility and effectiveness of our proposed co-design.

ARCH-COMP20 Category Report: Hybrid Systems with Piecewise Constant Dynamics and Bounded Model Checking

This report presents the results of a friendly competition for formal verification of continuous and hybrid systems with piecewise constant dynamics. The friendly competition took place as part of the workshop Applied Verification for Continuous and Hybrid Systems (ARCH) in 2020. In this fourth edition, five tools have been applied to solve six different benchmark problems in the category for piecewise constant dynamics: BACH, PHAVerLite, PHAVer/SX, TROPICAL, and XSpeed. Compared to last year, we combine the HBMC and HPWC categories of ARCH-COMP 2019 to a new category PCDB (hybrid systems with Piecewise Constant bounds on the Dynamics (HPCD) and Bounded model checking (BMC) of HPCD systems). The result is a snapshot of the current landscape of tools and the types of benchmarks they are particularly suited for. Due to the diversity of problems, we are not ranking tools, yet the presented results probably provide the most complete assessment of tools for the safety verification of continuous and hybrid systems with piecewise constant dynamics up to this date