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New evidence of long-distance trade in Somaliland in Antiquity. Imported materials from the 2018‑2019 field seasons at Xiis (Heis), 1st to 3rd centuries AD
Full text linkThe coast of Somaliland was the scenario of intense interactions between merchants and local pastoralists in Antiquity, as part of the Indian Ocean trade pattern. The site of Heis (Xiis in Somali) is a large necropolis, consisting of hundreds of cairns, on the coast of eastern Somaliland. It is known since the late 19th century for its remarkable evidence of trade with the Roman Empire, but it has not been the object of systematic research until 2017. In this chapter, we present new data from surveys and excavations conducted during two f ield seasons, focusing on imported materials (pottery and glass), mainly from the Roman and Parthian empires and South Arabia, between the 1st and 3rd centuries AD. Imported materials represent 99% of all artefacts documented in survey and excavation. This research is part of an ongoing project on long-distance trade in Somaliland.La côte du Somaliland fut le lieu d’interactions intenses entre les marchands et les pasteurs locaux durant l’Antiquité, dans le cadre du développement du commerce dans l’océan Indien. Le site de Heis (Xiis en somali) abrite une vaste nécropole, constituée de centaines de cairns, sur la côte du Somaliland oriental. Il est connu depuis la fin du xixe siècle pour ses vestiges remarquables qui matérialisent l’intensité des échanges avec l’Empire romain. Mais il n’avait pas fait l’objet de recherches systématiques avant 2017. Dans cet article, nous présentons des données nouvelles provenant de prospections et de fouilles menées pendant deux saisons de terrain, en nous concentrant sur le matériel importé (céramique et verre), en provenance notamment des empires romain et parthe et d’Arabie du Sud, et daté du ier et du iiie siècles ap. J.‑C. Les importations représentent 99 % de tous les objets documentés lors des prospections et des fouilles. Cette recherche s’inscrit dans le cadre d’un projet en cours sur le commerce à longue distance au Somaliland.Agencia Estatal de Investigación | Ref. PGC2018-099932-B-I0
Permian lobed Zoophycos as the product of the terrestrialization process: Behavioral innovation in the Tahkandit Limestone (Yukon River, Alaska, USA)
No full textPaleontological survey in the remote Yukon-Charley Rivers National Preserve in Alaska led to the discovery of lobed Zoophycos from the lower Tahkandit Limestone (informally named Sandstone unit), an interval characterized by grayish-green glauconitic sandstone and conglomerate of coastal origin. The studied Zoophycos consists of a lobate skirt-like spreite bounded by a marginal tube. Smaller tongue-shaped lobes branch off from larger parent lobes that share the same tongue-like shape. Sedimentological features, together with body fossils and associated trace fossils (Planolites, Chondrites), indicate a shoreface habitat for the Zoophycos producer. This shallow-marine environmental setting is in contrast with the deeper bathymetries in which lobed Zoophycos are recovered in post-Palaeozoic times. The producer of the lobed Zoophycos of the Yukon River is interpreted as a deposit-feeder that used sensory-driven, directed search for locating heterogeneously distributed trophic resources. The Zoophycos producer filled its burrow with Coprolus-like fecal pellets, possibly complementing deposit feeding with microbial gardening and/or food caching. Data presented here provide useful insight into the morphological evolution and bathymetric distribution of Zoophycos, suggesting two ‘Golden Ages’ for lobed Zoophycos: (1) Carboniferous–Permian and (2) Cretaceous–Neogene. This stratigraphic distribution supports the important ecological role of major terrestrialization events, that are, the Palaeozoic expansion of land plants and the Mesozoic expansion of angiosperms. The consequent increased input of nutrients to coastal areas was an important contributor to declining trends in porewater oxygen concentrations. This phenomenon favored adaptive traits to exploit nutrient-rich but oxygen-poor niches, among which the U-shaped marginal tube of lobed Zoophycos was an efficient adaptation to bring oxygenated water into low-oxygen substrates.Fondazione Alma Mater, Professor G. Gabbianelli (Dipartimento di Scienze Biologiche, Geologiche e Ambientali, Università di Bologna, Italy)CAMBIACLIMA project (University of Genova)Agencia Estatal de Investigación | Ref. FJC2020-044836-
Acquisition activity: do firm age and family control matter?
Full text linkThis article examines the relationship between firm age and acquisition activity and how family and non-family firms differ in the number of acquisitions they undertake. Inspired by previous research requiring firm age as a focal aspect and literature studying the antecedents of acquisitions, we draw on the SEW perspective to test our hypotheses based on the analysis of the acquisition activity of Asia-Pacific public firms. Our empirical findings support a U-shaped relationship between firm age and acquisition activity. Moreover, the findings reveal that family firms engage in fewer acquisitions than non-family firms irrespective of the age of the firm.Universidad de Málaga/CBU
High-frequency impedance measurements on cement paste loaded with steel fibres
Full text linkConducting fibre-reinforced cement-based materials is of great technological interest for their mechanical performance and multifunctional character, from structural to self-sensing applications. The composite's properties depend mainly on the fibre's concentration. However, for a given nominal concentration, the critical practical aspect is the degree of dispersibility achieved during the mixing process. This unsolved problem that greatly conditions the reproducibility of mixes. The present research addresses this problem using the electrochemical impedance spectroscopy technique.
Different cement paste model samples were loaded with stainless steel wires acting as reinforcing fibres. The system's impedance was recorded mainly from 50 MHz to 20 Hz, but lower frequencies were also explored. The results show that the presence of fibres modifies the impedance spectra, decreasing the apparent resistivity measured. This result was already reported in the literature. What is new in this research is the fact that the orientation of the fibres with respect to the electric field used for testing significantly affects the impedance spectra. The numerical simulations show that the presence of fibres modifies the current lines in a manner largely dependent on the ratio of the interfacial impedance to the cementitious impedance, which defines the minimal size for resolving orientation effectsXunta de Galicia | Ref. ED431B 2024/25Agencia Estatal de Investigación | Ref. PID2022-137096OB-I00Universidade de Vigo/CRUE-CSI
Strategies to maximize the dopant‐to‐exciton emission ratio in Mn‐Doped CsPbCl 3 nanocrystals
Full text linkDoping CsPbCl 3 perovskite nanocrystals (NCs) with Mn 2+ has gained attention due to their interesting emission properties. However, the photoluminescence (PL) spectra of these NCs display both dopant and exciton emission peaks. It is critical to achieve color purity for light–emitting diode (LED) applications, but the factors that govern this remain unclear. Herein, a systematic investigation of the factors determining the exciton‐to‐dopant energy transfer process in Mn 2 ⁺‐doped CsPbCl 3 NCs is presented to reveal how the exciton‐to‐Mn 2 ⁺ emission ratio can be maximized. These findings indicate that this process is not only affected by dopant concentration and halide (Cl/Br) composition, but also by the co‐dopants used, as well as surface passivation. These factors can potentially account for the discrepancies in the exciton‐to‐dopant emission ratios across the literature. These results show that post‐synthetic surface passivation of Mn 2 ⁺‐doped CsPbCl 3 NCs with quaternary ammonium salt, such as dimethyldidodecylammonium chloride (DDACl), drastically enhances the exciton‐to‐Mn 2 ⁺ emission ratio, achieving a two‐fold increase. Ultrafast pump‐probe spectroscopy surprisingly reveals that the passivation can introduce shallow trap states that enhance energy transfer to dopant sites and influence overall luminescence efficiency through non‐radiative decay processes. This study sets guidelines for maximizing dopant emission in doped perovskite NCs.Universidade de Vigo/CISUGAgencia Estatal de Investigación | Ref. RYC2018-026103-IAgencia Estatal de Investigación | Ref. PID2023-147567NB-I00Agencia Estatal de Investigación | Ref. TED2021-131628A-I00Agencia Estatal de Investigación | Ref. CNS2022-13553
Automatic detection and segmentation of columns in as-built buildings from point clouds
Full text linkOver the past few years, there has been an increasing need for tools that automate the processing of as-built 3D laser scanner data. Given that a fast and active dimensional analysis of constructive components is essential for construction monitoring, this paper is particularly focused on the detection and segmentation of columns in building interiors from incomplete point clouds acquired with a Terrestrial Laser Scanner. The methodology addresses two types of columns: round cross-section and rectangular cross-section. Considering columns as vertical elements, the global strategy for segmentation involves the rasterization of a point cloud onto the XY plane and the implementation of a model-driven approach based on the Hough Transform. The methodology is tested in two real case studies, and experiments are carried out under different levels of data completeness. The results show the robustness of the methodology to the presence of clutter and partial occlusion, typical in building indoors, even though false positives can be obtained if other elements with the same shape and size as columns are present in the raster
Ranpo and Maruo, mirror images of eroguro
Full text linkEl presente artículo plantea las figuras de Edogawa Ranpo y Maruo Suehiro como reflejos especulares de unos mismos paradigmas estilísticos y temáticos dentro de sus respectivos medios. Se defenderá la idea de que Maruo configura, desde la década de 1980, el manga eroguro canónico, es decir, una transposición de los rasgos identificativos del eroguro original al medio del manga, y que, como consecuencia, es el artista que mejor reproduce el espíritu de esa corriente artística en las adaptaciones al manga de la obra de Edogawa Ranpo. Para ello, se analizarán las principales características del movimiento, del que Ranpo es el máximo representante, así como las situaciones políticas y sociales, referentes y presupuestos conceptuales que dieron origen a esta importante tendencia artística. Se analizará hasta qué punto esos rasgos están presentes también en el imaginario de Maruo. Por último, se hará una comparativa entre las diferentes adaptaciones al manga de la obra de Ranpo, con el fin de determinar si efectivamente Maruo es la traslación ideal del espíritu del eroguro original al manga.This article presents Edogawa Ranpo and Maruo Suehiro as mirror images of the same stylistic and thematic paradigms within their respective media. It will argue that, since the 1980s, Maruo has shaped canonical eroguro manga, that is, a transposition of the identifying features of the original eroguro to the medium of manga, and that, as a result, he is the artist who best reproduces the spirit of this artistic movement in his manga adaptations of Edogawa Ranpo's work. To this end, we will analyse the main characteristics of the movement, of which Ranpo is the leading representative, as well as the political and social situations, references and conceptual assumptions that gave rise to this important artistic trend. We will analyse the extent to which these features are also present in Maruo's imagination. Finally, a comparison will be made between the different manga adaptations of Ranpo's work, in order to determine whether Maruo is indeed the ideal translation of the spirit of the original eroguro into manga.Keywords:Ranpo, Maruo, eroguro, grotesque, abjection
Low-cost aerial unit for outdoor inspection of building façades
No full textGeometry of buildings is an essential measurement during energy inspections, since it has a great influence in the energy performance of the building. Given the difficult access presented to some areas of the buildings that make impossible their complete geometric characterization with terrestrial devices, Unmanned Aerial Vehicles (UAVs) stand as the solution for the acquisition of data both from façades and roofs. In this paper, the potential of UAV to building geometric inspection is analyzed by mounting a Kinect sensor for geometric data acquisition in three-dimensions. The resulting point cloud and 3D model are evaluated in order to validate the performance of the complete system.Xunta de Galici
Actividades, propostas e recomendacións para o desenvolvemento turístico de Vilalba
No full textO informe que realizamos a continuación analiza a Vilalba como un importante territorio, capital
da Terra Chá, e núcleo de referencia da provincia de Lugo pola súa localización centralizada e o seu
relevante papel como centro administrativo, socio-económico e cultural. Este territorio posúe un
gran patrimonio cultural estendido nas súas 30 parroquias, con elementos singulares, un interesante
patrimonio natural, que pon en valor a súa paisaxe e unha tradición gastronómica recoñecida.
Este informe elabórase co obxectivo de proporcionar; por unha banda, unha visión sistémica de todos os
elementos que caracterizan o sistema turístico de Vilalba, e por outro, de achegar unha serie de propostas
e ferramentas de actuación con respecto ao desenvolvemento dunha estratexia de actuación turística.
A estrutura do documento correspóndese cunha serie de capítulos que abordarán, nun primeiro
momento, a análise territorial que contextualiza a Vilalba. Identificando deste xeito aqueles factores
de tipo estrutural que inciden na evolución do turismo, analizando os elementos naturais e culturais
do territorio obxecto de estudo e elementos socioeconómicos que explican as características da
actualidade poboacional do municipio.
Posteriormente, profundamos polo miúdo na composición do sistema turístico de Vilalba, desglosando
tres dimensións fundamentais: análise de recursos turísticos dispoñibles, relación entre a oferta e a
demanda turística e análise da superestructura do concello vilalbés. Deste xeito, quérese dar unha
comprensión sinxela á complexidade e diversidade de elementos interrelacionados do sector turístico
do concello.European Union Interreg Europe programme ERDF (POCTEP
Application of synthetic storm technique for rain attenuation prediction at Ka and Q band for a temperate Location, Vigo, Spain
No full textTime series prediction of rain attenuation from rain rate measurement during rain is made by using Synthetic Storm Technique (SST) for Ka and Q band signal for a temperate location, Vigo, Spain. Rain rate and rain attenuation data for the three year measurement period from 2016 to 2018 have been used to test the validity of the SST model at the present location. As we move from the Ka band to the Q band, larger value of predicted rain attenuation for the same rain rate is observed. For a single rain event, better prediction depends on the actual storm speed measured for the present location. But the long term statistics of predicted rain attenuation are insensitive to storm translation speed. Applicability of the SST model is tested for predicting diurnal, monthly and yearly statistics. Comparison between prediction and measurements are done for both first (rain attenuation occurrence) and second order (fade duration) statistics. Good matching has been observed between prediction and measurement for single rain event as well as for long term statistics. Prediction errors are found to be less than 0.5 dB in all the cases which proves the efficiency of the SST model for the present location.ESA/ESTECEuropean State Agenc