Geometry of curves and surfaces in contemporary chair design

In the present work, we focus on some of the current trends used in furniture design, from a dual point of view: differential geometry of curves and surfaces, and the existing perspective deriving from the usual techniques of computer-aided design. The contributions of architects such as Alvar Aalto, Mies van der Rohe, Marcel Breuer, Arne Jacobsen and Charles and Ray Eames to contemporary chair design are related to these techniques. Among them, we point out those which are performed by means of spatial geometric transformations of curves and surfaces, with an emphasis on ruled surfaces

A scalar approximation to the survey of the architectural, artistic and cultural heritage of the University of Alcalá (Madrid, Spain)

This work presents part of the experience accumulated by the research team of which the authors are members in data collection and information management for the representation of architectural and artistic heritage. To do so, we will analyze the results according to the characteristics of the elements to be studied, which we shall classify according to their scale, location, and nature. In this sense, we propose three working approaches: the L scale, linked to exterior urban spaces, the M scale, for buildings and their interiors, and the S scale, for movable objects and sculptures. Likewise, we address an aspect that is not often dealt with in scientific publications, such as the importance of the graphic planning of tasks and timings in order to make campaigns more efficient. In addition, we performed a critical analysis of the workflows prioritizing the characteristics of the object and the physical constraints that researchers in this field must overcome. As a case study, we shall use the Chapel of San Ildefonso, the foundational space of the University of Alcalá (Madrid), declared a World Heritage Site by UNESCO. The heritage qualities of this space allow us to test and exemplify the work process according to the aforementioned scales of approximation. That is to say, the facade as an example of urban scale (L), the wooden coffered ceiling as the main element of the buildings interior (M) and the tomb of Cardinal Cisneros and the adjacent altarpiece as an example of movable scale (S). In short, the contribution is a reference for the effective planning and execution of the survey process, as well as for the processing of the models discussed

Veinte años de bienales españolas de arquitectura y urbanismo. Vanguardia y difusión de la arquitectura

El presente trabajo estudia la imagen compuesta por un conjunto de obras de arquitectura y urbanismo llevadas a cabo en España a lo largo de veinte años. Para encuadrar el grupo he tomado como base la selección que la Bienal Española de Arquitectura y Urbanismo ha venido realizando como premio a nivel nacional. Éste es un certamen establecido en el año 1991 por el entonces Ministerio de Obras Públicas y Urbanismo, actual Ministerio de Fomento. Desde sus comienzos se ha planteado como una antología coral, que reúne más de trescientos trabajos, principalmente equipamientos, viviendas, actuaciones urbanas, etc. en su mayoría de promoción pública, bajo el paraguas común del reconocimiento de la calidad. Se puede afirmar que frente a otros premios éste se diferencia por su voluntad de reivindicación de la "industria arquitectónica nacional". El jurado de la Bienal, se ha nutrido de arquitectos de reconocido prestigio, que han proyectado a través de sus selecciones, una visión particular de la arquitectura española. Han presentado a la sociedad aquellas obras que consideran más excelentes, no tanto las que representan la realidad media ni lo más conocido por el público, sino una visión ligada a una concepción profesional de la arquitectura, ignorando la mayoría de las grandes obras icónicas que se han realizado en España en los últimos veinte años. La apertura a las corrientes internacionales de la arquitectura española era generalizada ya en los años ochenta, pero a principio de los noventa se produce una ruptura con las corrientes revisionistas del movimiento moderno, tanto interiores como foráneas, dominantes en ese momento. Éstas se dejan a un lado para volver al lenguaje moderno más ortodoxo. Se ponen en valor especialmente los pioneros de la arquitectura moderna española: De La Sota, Coderch, Oiza, Sostres, Corrales y Molezún, etc. y el espíritu racionalista aflora no ya como una búsqueda de lenguaje sino como una refundación disciplinar. Los años dos mil derivarán hacia una mayor libertad formal, y una creciente exuberancia en los acabados: efectos ilusorios, lo translúcido, capas, pieles múltiples, etc. surgen con energía. Como difusión de la propia investigación se han publicado varios artículos que tratan distintos aspectos de la arquitectura contemporánea, tales como la vivienda, la rehabilitación, la expresión gráfica o el urbanismo, analizados a través de la óptica que la privilegiada visión de la Bienal ha ofrecido

Un artesonado poliédrico manierista en Castroverde de Campos (Zamora, España)

This paper analyses an outstanding case in the field of historic Spanish carpentry. Built in the sixteenth century, the fivepanel wood coffered ceiling in the church of Santa María del Río in Castroverde de Campos (Zamora, Spain) shows a Renaissance layout with polygonal coffers. It combines Hispano-Islamic technological heritage with some innovative features, including singular disposition of timber, duplicity of structures and unorthodox carpentry joints. Furthermore, convex coffers are introduced among traditional concave ones giving it a marked Mannerist appearance. The likely double role of the author as designer and contractor explains the relevance of prefabricated elements in the construction process of the ceiling, since this effort for modulation and systematization rationalizes procedures and reduces labour costs.Este artículo analiza un caso excepcional en la carpintería de armar en España. Se trata del artesonado de cinco paños de la iglesia de Santa María del Río, en Castroverde de Campos (Zamora). Construido en el s. XVI, con una trama de artesones poligonales en su intradós, combina el diseño renacentista con la tradición técnica hispano-musulmana de estructuras de madera, y presenta aportaciones novedosas como la inusual disposición de escuadrías, la duplicidad de estructuras y las poco ortodoxas uniones carpinteras utilizadas. Además, la introducción de artesones convexos junto a los convencionales artesones cóncavos le confiere un marcado aspecto manierista y resuelve ingeniosamente el encuentro entre paños. La muy posible coincidencia de diseñador y constructor en la misma persona explicaría un proceso de construcción con módulos prefabricados, con el consiguiente ahorro de costes y riesgos laborales

Generative capacities of cellular automata codification for evolution of NN codification

Proceeding of: International Conference on Artificial Neural Networks. ICANN 2002, Madrid, Spain, August 28-30, 2002Automatic methods for designing artificial neural nets are desired to avoid the laborious and erratically human expert’s job. Evolutionary computation has been used as a search technique to find appropriate NN architectures. Direct and indirect encoding methods are used to codify the net architecture into the chromosome. A reformulation of an indirect encoding method, based on two bi-dimensional cellular automata, and its generative capacity are presented.Publicad

The moderator role of Gender in the Unified Theory of Acceptance and Use of Technology (UTAUT): A study on users of Electronic Document Management Systems

Venkatesh et al. [1] tried to integrate predictability capabilities from the different existing models of technology acceptance. This produced the Unified Theory of Acceptance and Use of Technology (UTAUT). This comprehensive model resulted in the identification of common aspects. It proposed several constructs with a greater explanatory power and analyzed moderating drivers, such as age, Gender, experience and voluntariness of use. By doing so, UTAUT identifies three major drivers of behavioral intention: performance expectancy, effort expectancy and social influence. On the other hand, facilitating conditions and behavioral intention were identified as determinant factors of actual use [1]. In addition to previous considerations about UTAUT, empirical research has scarcely analyzed the moderating role of Gender [2]. This is why this paper particularly aims to fill this gap. Hofstede [3] describes strength, competitiveness and guidance for material success as social roles linked to male values, whilst modesty, tenderness, sensitivity and concern for the quality of life are values associated with women. With respect to UTAUT, existing studies have shown that performance expectancy positively influences behavioral intention more strongly for men (cf. [4], [5], [6] and [7]). Moreover, it has been observed that effort expectancy positively influences behavioral intention more strongly for women (cf. [4], [5] and [6]), while social influence positively affects behavioral intention more strongly for women (cf. [5], [7] and [8]). In our research, with the aim of testing the moderating effects of Gender, a sample of 2,175 users of Electronic Document Management Systems (EDMS) in Portuguese municipalities was used. Taking into account that Gender is a categorical variable, we have adopted a multi-group or multi-sample analysis [9] -dividing the sample into two groups (male = 748; female = 1,427) and estimating each group of observations separately. Before comparing the groups, an analysis of the measurement invariance was carried out to make sure that the construct measures were invariant between both groups [10]. Once the metric invariance had been assessed, we carried out a set of multi-group analyses –interpreting statistically-significant differences in path coefficients as moderating effects. On the one hand, the parametric approach considering both equal variances and different variances has been used [11, 12]. On the other hand, we have applied non-parametric approaches exemplified by the permutation test [13], and Henseler’s PLS multi-group analysis [10, 12, 14]. This study notes slight differences in the results of the aforementioned methods. As a result, the moderating effect of Gender on the relation between performance expectancy and behavioral intention showed that this relationship is stronger among men than women. Finally, a discussion on the implications of Gender as a moderator for the UTAUT model is included

Determinants of User Acceptance of a Local eGovernment Electronic Document Management System (EDMS)

On numerous occasions the significant value of the investments involved in the development of eGovernment and the expectations of governmental information systems use do not correspond to the rate of effective use. This scenario makes it difficult to justify the development of electronic government by governments and local authorities among its citizens. It is therefore important to understand the factors that influence the employees' intention of using governmental information systems. With the aim of understanding the determining factors of using an Electronic Document Management System (EDMS) in the context of Portuguese municipalities, this study develops an empirical analysis using the Unified Theory of Acceptance and Use of Technology (UTAUT) model, (Venkatesh et al., 2003). This model's application for information systems research in the governmental context has a weak expression and is unique in EDMS research. This empirical research follows a realist and positivist approach. Data was collected from a survey answered by 2,175 employees of Portuguese municipalities (EDMS users). Partial Least Squares (PLS) was used to test the model proposed. The results showed that Intention to Use is positively affected by Performance Expectancy, Effort Expectancy, Social Influence and Facilitating Conditions. With respect to the EDMS Use, the results showed that it is positively influenced by Intention to Use and Facilitating Conditions. The main result indicates that EDMS users believe that the use of this information system will help them to obtain performance benefits in their work. However, the increasing use of EDMS is not very influenced by the system's perceived ease of use. In short, this study provides a contribution to the Information Systems Acceptance and Adoption literature in local eGovernmental contexts. In addition, our contribution empirically tests the model for implementation in governmental organizations and provides a better understanding of the adoption and use of an EDM

Geometrical Analysis of a Brick Vault by Slices from the Aurelian Walls in Rome

This work focuses on the analysis of a singular case of brick vault by slices from the Aurelian Walls in Rome. The study is based on an accurate survey carried out through automated photogrammetry. This analysis aims to determine the geometry of the vault and compare it with the theoretical model of its type.Open Access funding provided thanks to the CRUE-CSIC agreement with Springer Nature. This paper is part of the research project "The construction of brick vaults by slices. Historical uses and current possibilities" PID2020-116191 GB-I00, funded by MCIN/AEI/https://doi.org/10.13039/50110001103