Internet sales as a new mode of internationalization

The way that organizations explore the Internet has been the focus of a substantial body of scientific studies and non-academic reflection. The main goal of this study is to analyze the potential of the internet as a mode of internationalization and the factors that influence the results of the adoption of this mean to access foreign markets. For this purpose, we examine the determinants of the level of international sales made via internet estimating an ordered probit model. The results show that the importance of previous experience in using the internet and developing international activity, together with the level of internet marketing budget , the level of investment on internet sophistication, the firm dimension, the business age and the type pf activity are variables that determine the results obtain in the international sales trough the internet.info:eu-repo/semantics/publishedVersio

Evaluation of upper limb joint contribution to racket head speed in elite tennis players using IMU sensors: comparison between the cross-court and inside-out attacking Forehand Drive

This study aimed to quantify and compare the upper limb angular kinematics and its contributions to the racket head speed between the cross-court (CC) and inside-out (IO) attacking tennis forehand of elite tennis players in a competitive environment. A new approach was used to study the forehand drive with mini-inertial sensors of motion capture to record the kinematic data. Six strokes in each direction per participant (72 shots in total) were chosen for analysis. Upper limb kinematics were calculated in the Visual 3D platform (Visual 3D Professional V5.01.21, C-motion, Germantown, MD, USA). The method used to calculate the upper limb’s contributions was performed with MATLAB software and used the segment’s (upper arm, forearm and hand) angular velocities and their respective displacement vectors obtained through the inertial sensors. Upper limb kinematics demonstrated a higher shoulder rotation in the IO direction with significant differences at the end of the backswing, which could be a key factor in distinguishing the two directions of the shot. Results also demonstrated that the horizontal flexion of the upper arm (around the shoulder joint) was primarily responsible for the racket velocity in the anteroposterior direction (48.1% CC and 45.2% IO), followed by the extension of the forearm (around the elbow joint) (17.3% CC and 20.9% IO) and the internal rotation of the upper arm (around the shoulder joint) (15.6% CC and 14.2% IO). No significant differences were shown in the contributions of upper limbs to the racket head velocity between the two directions of the shot. Tennis coaches and players should develop a specific training programme to perform higher angular velocities in these specific joint rotations.info:eu-repo/semantics/publishedVersio

Neotectonic activity on the Carcavai fault zone (Algarve, Portugal)

Studies performed on the Carcavai fault zone, Eastern Algarve, revealed several deformational features in Plio-Quaternary sediments with potential neotectonic implications. These features include fracturing (faults and joints) and clastic dikes, located along the Carcavai fault. Most of the fractures appear to be the expression of the fault activity affecting the Plio-Quaternary sediments. This is suggested by a consistent strike, subparallel to the major tectonic structure, and by the location pattern. Evidences of the fault activity were also identified in the Mesozoic and Paleozoic rocks, though the age of that deformation is poorly constrained. It consists in the presence of zones of intensely brecciated rock and of adjoining coarse sedimentary deposits probably related to the dismantling of a fault scarp. The acquired data point to a late hercynian structure, reactivated as a left-lateral strike-slip fault with a thrust component during the Plio-Quaternary

Estudos de neotectónica na falha de Carcavai, Algarve Oriental

Estudos levados a cabo na zona da falha de Carcavai revelaram a ocorrência de deformações (fracturação e filões detríticos) em sedimentos plio-quaternários, indicando actividade neotectónica. A generalidade das fracturas aparenta corresponder à expressão superficial secundária da actividade naquela zona de falha. Os dados adquiridos apontampara uma zona de falha complexa de desligamento esquerdo, com componente vertical inversa, desde o final do Mesozóico ou início do Cenozóico. Os filões detríticos foram interpretados como estruturas resultantes de liquefacção induzida sismicamente

The 1909 Benavente (Portugal) earthquake : search for the source

The Lower Tagus River Valley has been affected by severe earthquakes comprising distant events, as in 1755, and local earthquakes, as in 1344, 1531, and 1909. The 1909 earthquake was located NE of Lisbon, near Benavente, causing serious damage and many losses. Mw 6.0 has been assessed for this earthquake and a reverse faulting focal mechanism solution has been calculated. Poor epicenter location, possible directivity and site effects, low fault slip rates, and the thick Cenozoic sedimentary cover make difficult correlation with regional structures. The focal mechanism indicates an ENE reverse fault as source, though it does not match any outcropping active structure suggesting that the event could have been produced by a blind thrust beneath the Cenozoic sedimentary fill. Hidden sources, inferred from seismic reflection data, are a possible NE structure linking the Vila Franca de Xira and the Azambuja faults, or the southern extension of the later. Evidence of surface rupturing is inhibited by the thick Holocene alluvial cover and the high fluvial sedimentation rate, though a slightly depressed area was identified in the Tagus alluvial plain W of Benavente which was investigated as possible geomorphic evidence of co-seismic surface deformation. A high-resolution seismic reflection profile was acquired across a 0.5 m high scarp at this site, and two trenches were opened across the scarp for paleoseismic research. Some deformation of dubious tectonic origin was found, requiring further studies

A modeling domain-specific language for IoT-enabled operating systems

With the increased complexity of low-end devices in the Internet of Things (IoT), mainly due to the connectivity and interoperability requirements, the development and configuration of embedded operating systems (OSes) for such devices is not straight forward. The complexity of the communication requirements is usually mitigated by the OS, e.g., the Contiki-OS, as it already incorporates an IoT-compliant network stack. Yet, the configuration of such stack requires major knowledge on the code structure, leading to additional development time, particularly when the network comprises several wireless nodes and individual configurations with subsequent firmware that needs to be generated. Based on a developed software modeling domain-specific language, this paper presents the EL4IoT framework. It aims to reduce and ease the development time by promoting a design automation tool that can configure, and automatically generate code (ready to compile) for low-end IoT devices running the Contiki-OS. Although leveraging the whole Contiki-OS modeling, this work only refactored and modeled the network stack while approaching the OS itself as one big building block or component. The proposed approach can be extended to other IoT-enabled OSes as well as integrated in other design automation tools.This work has been supported by COMPETE: POCI-01-0145-FEDER-007043 and FCT - Fundação para a Ciência e Tecnologia within the Project Scope: UID/CEC/00319/2013. Tiago Gomes is supported by FCT PhD grant SFRH/BD/90162/2012

Improving land cover classification using genetic programming for feature construction

Batista, J. E., Cabral, A. I. R., Vasconcelos, M. J. P., Vanneschi, L., & Silva, S. (2021). Improving land cover classification using genetic programming for feature construction. Remote Sensing, 13(9), [1623]. https://doi.org/10.3390/rs13091623Genetic programming (GP) is a powerful machine learning (ML) algorithm that can produce readable white-box models. Although successfully used for solving an array of problems in different scientific areas, GP is still not well known in the field of remote sensing. The M3GP algorithm, a variant of the standard GP algorithm, performs feature construction by evolving hyperfeatures from the original ones. In this work, we use the M3GP algorithm on several sets of satellite images over different countries to create hyperfeatures from satellite bands to improve the classification of land cover types. We add the evolved hyperfeatures to the reference datasets and observe a significant improvement of the performance of three state-of-the-art ML algorithms (decision trees, random forests, and XGBoost) on multiclass classifications and no significant effect on the binary classifications. We show that adding the M3GP hyperfeatures to the reference datasets brings better results than adding the well-known spectral indices NDVI, NDWI, and NBR. We also compare the performance of the M3GP hyperfeatures in the binary classification problems with those created by other feature construction methods such as FFX and EFS.publishersversionpublishe