Papers by LUIS EDUARDO HERNANDEZ ALONSO
arXiv: Computers and Society, Oct 26, 2016
Tourism has been an increasingly important factor in global economy, society and environment, acc... more Tourism has been an increasingly important factor in global economy, society and environment, accounting for a significant share of GDP and labor force. Policy and research on tourism traditionally rely on surveys and economic datasets, which are based on small samples and depict tourism dynamics at low spatial and temporal granularity. Anonymous call detail records (CDRs) are a novel source of data, showing enormous potential in areas of high societal value: such as epidemics, poverty, and urban development. This study demonstrates the added value of using CDRs for the formulation, analysis and evaluation of tourism strategies, at the national and local levels. In the context of the European country of Andorra, we use CDRs to evaluate marketing strategies in tourism, understand tourists' experiences, and evaluate revenues and externalities generated by touristic events. We do this by extracting novel indicators in high spatial and temporal resolutions, such as tourist flows per country of origin, flows of new tourists, tourist revisits, tourist externalities on transportation congestion, spatial distribution, economic impact, and profiling of tourist interests. We exemplify the use of these indicators for the planning and evaluation of high impact touristic events, such as cultural festivals and sports competitions. 1
Proceedings of the 40th International Conference on Software Engineering: Companion Proceeedings, 2018
A fundamental aspect in the requirements engineering process is to know the quality of a specific... more A fundamental aspect in the requirements engineering process is to know the quality of a specification, including how the quality evolves over time. is paper introduces an industrial approach for analysis of requirements quality evolution. e approach has been implemented in the System ality Analyzer tool, exploits quality metrics for requirements correctness, consistency, and completeness, and is based on the storage of quality information in snapshots that are combined and displayed in charts. is can help practitioners to assess the progress and status of a requirements engineering process and to make decisions.
2018 IEEE/ACM 40th International Conference on Software Engineering: Companion (ICSE-Companion), 2018
A fundamental aspect in the requirements engineering process is to know the quality of a specific... more A fundamental aspect in the requirements engineering process is to know the quality of a specification, including how the quality evolves over time. This paper introduces an industrial approach for analysis of requirements quality evolution. The approach has been implemented in the System Quality Analyzer tool, exploits quality metrics for requirements correctness, consistency, and completeness, and is based on the storage of quality information in snapshots that are combined and displayed in charts. This can help practitioners to assess the progress and status of a requirements engineering process and to make decisions.
IEEE Journal of Biomedical and Health Informatics, 2021
Throughout the COVID-19 pandemic, nonpharmaceutical interventions, such as mobility restrictions,... more Throughout the COVID-19 pandemic, nonpharmaceutical interventions, such as mobility restrictions, have been globally adopted as critically important strategies to curb the spread of infection. However, such interventions come with immense social and economic costs and the relative effectiveness of different mobility restrictions are not well understood. Some recent works have used telecoms data sources that cover fractions of a population to understand behavioral changes and how these changes have impacted case growth. This study analyzed uniquely comprehensive datasets in order to examine the relationship between mobility and transmission of COVID-19 in the country of Andorra. The data consisted of spatiotemporal telecoms data for all mobile subscribers in the country, serology screening results for 91% of the population, and COVID-19 case reports. A comprehensive set of mobility metrics was developed using the telecoms data to indicate entrances to the country, contact with tourists, stay-at-home rates, trip-making and levels of crowding. Mobility metrics were compared to infection rates across communities and transmission rate over time. All metrics dropped sharply at the start of the country's lockdown and gradually rose again as the restrictions were gradually lifted. Several of these metrics were highly correlated with lagged transmission rate. There was a stronger correlation for measures of indoor crowding and inter-community tripmaking, and a weaker correlation for total trips (including intra-community trips) and stay-at-homes rates. These findings provide support for policies which aim to discourage gathering indoors while lifting the most restrictive mobility limitations.
CityScope: A Data-Driven Interactive Simulation Tool for Urban Design. Use Case Volpe
Unifying Themes in Complex Systems IX, 2018
MIT City Science Group (CS) studies the interaction of social, economic and physical characterist... more MIT City Science Group (CS) studies the interaction of social, economic and physical characteristics of urban areas to understand how people use and experience cities with the goal of improving urban design practices to facilitate consensus between stakeholders. Long-established processes of engagement around urban transformation have been reliant on visual communication and complex negotiation to facilitate coordination between stakeholders, including community members, administrative bodies and technical professionals. City Science group proposes a novel methodology of interaction and collaboration called CityScope, a data-driven platform that simulates the impacts of interventions on urban ecosystems prior to detail-design and execution. As stakeholders collectively interact with the platform and understand the impact of proposed interventions in real-time, consensus building and optimization of goals can be achieved. In this article, we outline the methodology behind the basic analysis and visualization elements of the tool and the tangible user interface, to demonstrate an alternate solution to urban design strategies as applied to the Volpe Site case study in Kendall Square, Cambridge, MA.
Sustainability, 2020
The MIT Media Lab City Science Group reshapes and reevaluates well-being as an emerging key indic... more The MIT Media Lab City Science Group reshapes and reevaluates well-being as an emerging key indicator due the social challenges that cities are facing, such as inequality, police violence, and breaches to safety and security. Well-being in urban environments has been studied extensively, yet most research focuses on one aspect of well-being rather than multiple dimensions of well-being. Existing well-being indices that are used to compare well-being between different countries or to set a standards for well-being consider a variety of aspects that affect well-being, yet they are not specific to urban environments. When considering that no holistic and comprehensive research has been specifically conducted on well-being in urban environments, we research the relationship between the built features of an urban environment and well-being. In this paper, we propose a Well-Being Index composed of five urban indicators—Community Connectedness, Safety & Security, Physical Health, Mental He...
Journal of minimally invasive gynecology, Jan 6, 2018
Journal of minimally invasive gynecology, Jan 8, 2018
Journal of Minimally Invasive Gynecology, 2017
Frontiers in Plant Science, 2017
Leaf Optical Properties (LOPs) convey information relating to temporally dynamic photosynthetic a... more Leaf Optical Properties (LOPs) convey information relating to temporally dynamic photosynthetic activity and biochemistry. LOPs are also sensitive to variability in anatomically related traits such as Specific Leaf Area (SLA), via the interplay of intra-leaf light scattering and absorption processes. Therefore, variability in such traits, which may demonstrate little plasticity over time, potentially disrupts remote sensing estimates of photosynthesis or biochemistry across space. To help to disentangle the various factors that contribute to the variability of LOPs, we defined baseline variation as variation in LOPs that occurs across space, but not time. Next we hypothesized that there were two main controls of potentially disruptive baseline spatial variability of photosynthetically-related LOPs at our boreal forest site: light environment and species. We measured photosynthetically-related LOPs in conjunction with morphological, biochemical, and photosynthetic leaf traits during summer and across selected boreal tree species and vertical gradients in light environment. We then conducted a detailed correlation analysis to disentangle the spatial factors that control baseline variability of leaf traits and, resultantly, LOPs. Baseline spatial variability of the Photochemical Reflectance Index (PRI) was strongly influenced by species and to a lesser extent light environment. Baseline variability of spectral fluorescence derived LOPs was less influenced by species; however at longer near-infrared wavelengths, light environment was an important control. In summary, remote sensing of chlorophyll fluorescence has good potential to detect variation in photosynthetic performance across space in boreal forests given reduced sensitivity to species related baseline variability in comparison to the PRI. Our results also imply that spatially coarse remote sensing observations are potentially unrepresentative of the full scope of natural variation that occurs within a boreal forest.
Journal of diabetes and its complications, Jan 28, 2016
To evaluate the differences in corneal thickness between type 2 diabetes subjects with HbA1c unde... more To evaluate the differences in corneal thickness between type 2 diabetes subjects with HbA1c under 7.0% and non-diabetes subjects during their preoperative laser surgery examinations. The mean of five consecutive corneal thickness measurements at the central and mid-peripheral cornea was obtained by means of noncontact scanning-slit corneal topography (Orbscan Topography System II; Orbscan, Inc., Salt Lake City, UT, USA) in 35 myopic non-insulin dependent type 2 diabetes subjects (17 males and 18 females) and 48 healthy myopic controls (23 males and 25 females). The corneal thickness values at the central and mid-peripheral cornea were significantly higher in the diabetic group (p<.001). The diabetic subjects presented the highest thickness value in the superior cornea (n=22; 62.9%) followed by the nasal (n=9; 25.7%) and the temporal (n=4; 11.4%) cornea, but never in the inferior cornea. The control subjects presented the highest thickness value in the superior cornea (n=19; 39.6...
Experimental energy consumption of FSA and DQ for data collection scenarios
Sensors
Data collection is a key scenario for the Internet of Things because it enables gathering sensor ... more Data collection is a key scenario for the Internet of Things because it enables gathering sensor data from distributed nodes that use low-power and long-range wireless technologies to communicate in a single-hop approach. In such scenario the network is composed of one coordinator that covers a particular area and a large number of nodes, typically hundreds or thousands, that transmit data to the coordinator upon request. Considering this scenario, in this paper we experimentally validate the energy consumption of two Medium Access Control (MAC) protocols, Frame Slotted ALOHA (FSA) and Distributed Queuing (DQ). We model both protocols as a state machine and conduct experiments to measure the average energy consumption in each state and the average number of times that a node has to be in each state in order to transmit a data packet to the coordinator. The results show that FSA is more energy efficient than DQ if the number of nodes is known a priori because the number of slots per ...
The impact of cooperative physical layer network coding on multicast short range networks
2013 IEEE International Conference on Communications (ICC), 2013
ABSTRACT In this paper, we exploit the characteristics of physical layer network coding (PNC) in ... more ABSTRACT In this paper, we exploit the characteristics of physical layer network coding (PNC) in multicast short range communication (SRC) networks. We present a scalable scenario of partially overlapping SRC networks, where collisions are resolved through indirect inter-group cooperation based on the features of PNC. Our scenario consists of a central network and several peripheral networks. In our previous work we proved that the central network presents significant gains in terms of throughput, delay and energy efficiency when applying the proposed scheme. Here we explore the impact of that scenario on the peripheral networks through a decomposition approach and we prove that they also present significant performance gains.
INTELIGENCIA ARTIFICIAL, 2005
Primary Open Angle Glaucoma is an eye disease that can, eventually, cause irreversible damage to ... more Primary Open Angle Glaucoma is an eye disease that can, eventually, cause irreversible damage to the optic nerve. Because of this an accurate diagnosis at early stages of the disease is necessary to stop or delay its progression. Perimetry, one of the most important tests to detect glaucoma, gives a large amount of numerical data that is difficult to analyze. A number of approaches are described in the literature to overcome this problem, some of them using artificial neural networks, mainly MLP with BP. In this paper, a Hybrid Visual Field Classifier System is proposed, comprising a Self-Organizing Map (SOM) and a rule based expert system, integrating the knowledge that the SOM discovers with the expertise of the ophthalmologist. With this association, individual results of each component are improved up to a diagnostic precision of 97%.
Crystals, 2022
The new ligand HMeATSM, derived from condensation of 2-3-butanedione with 4-methyl-3-thiosemicarb... more The new ligand HMeATSM, derived from condensation of 2-3-butanedione with 4-methyl-3-thiosemicarbazide and 2,4-dimethyl-3-thiosemicarbazide, has been synthesized. Its reactivity with nickel(II) and zinc(II) nitrates was explored and the resulting complexes were thoroughly characterized by elemental analysis, conductivity, mass spectrometry, IR, 1H and 13C NMR spectroscopies and their structures were confirmed by single-crystal X-ray diffraction. The results showed that the complex [Ni(MeATSM)]NO3 1 is formed under every reaction condition. In contrast, the reaction with zinc(II) nitrate depends on the temperature and the presence of LiOH·H2O, leading to the obtaining of complexes [Zn(MeATSM)(OH2)](NO3) 2 and [Zn(Me2TS)2(OH2)](NO3)2 3. The crystal structures of complexes 1 and 2 show that the dissymmetric ligand acts as a N2S2 tetradentate monoanionic ligand. The structural preferences of the metals also determine the structure of the complexes: whereas nickel(II) is in a square-plan...
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Papers by LUIS EDUARDO HERNANDEZ ALONSO