TECNALIA Publications Repository
Welcome to TECNALIA Publications, the Institutional Repository of TECNALIA.
TECNALIA Publications main objective is to collect, preserve and disseminate the intellectual production resulting from the research activity of TECNALIA to generate transferable knowledge and contribute thereby to development and social progress.
Recent Submissions
A hierarchical algorithm for optimal plug-in electric vehicle charging with usage constraints
(2016) Cortés, Andres; Martínez, Sonia
We present a hierarchical offline coordination algorithm for charging of Plug-in Electric Vehicles (PEVs), in which PEVs aim to optimally charge their batteries, subject to usage constraints along the day. With this algorithm, each PEV adjusts its charging strategy according to the price information, which is provided by an aggregator, while usage schedule constraints are respected at every iteration. A non-anonymous version of the algorithm is able to operate under communication failures. Both versions of the algorithm are proven to converge to the set of optimal solutions of the charging problem. This solution is optimal in the sense that it minimizes the cost of the consumed energy by both PEV and non-PEV loads. The solution has a valley-filling profile, since it leads to a configuration where PEVs aim to charge at low demand hours, minimizing, if possible, load peaks that are known to degrade the performance of power systems. In order to show convergence, we present an invariance result for difference inclusions, which works under a set of assumptions where LaSalle invariance principle does not apply. The algorithm performance is demonstrated throughout simulations.
A hierarchical algorithm for optimal plug-in electric vehicle charging with usage constraints
(2016) Cortés, Andres; Martínez, Sonia
We present a hierarchical offline coordination algorithm for charging of Plug-in Electric Vehicles (PEVs), in which PEVs aim to optimally charge their batteries, subject to usage constraints along the day. With this algorithm, each PEV adjusts its charging strategy according to the price information, which is provided by an aggregator, while usage schedule constraints are respected at every iteration. A non-anonymous version of the algorithm is able to operate under communication failures. Both versions of the algorithm are proven to converge to the set of optimal solutions of the charging problem. This solution is optimal in the sense that it minimizes the cost of the consumed energy by both PEV and non-PEV loads. The solution has a valley-filling profile, since it leads to a configuration where PEVs aim to charge at low demand hours, minimizing, if possible, load peaks that are known to degrade the performance of power systems. In order to show convergence, we present an invariance result for difference inclusions, which works under a set of assumptions where LaSalle invariance principle does not apply. The algorithm performance is demonstrated throughout simulations.
A hierarchical algorithm for optimal plug-in electric vehicle charging with usage constraints
(2016) Cortés, Andres; Martínez, Sonia
We present a hierarchical offline coordination algorithm for charging of Plug-in Electric Vehicles (PEVs), in which PEVs aim to optimally charge their batteries, subject to usage constraints along the day. With this algorithm, each PEV adjusts its charging strategy according to the price information, which is provided by an aggregator, while usage schedule constraints are respected at every iteration. A non-anonymous version of the algorithm is able to operate under communication failures. Both versions of the algorithm are proven to converge to the set of optimal solutions of the charging problem. This solution is optimal in the sense that it minimizes the cost of the consumed energy by both PEV and non-PEV loads. The solution has a valley-filling profile, since it leads to a configuration where PEVs aim to charge at low demand hours, minimizing, if possible, load peaks that are known to degrade the performance of power systems. In order to show convergence, we present an invariance result for difference inclusions, which works under a set of assumptions where LaSalle invariance principle does not apply. The algorithm performance is demonstrated throughout simulations.
A hierarchical algorithm for optimal plug-in electric vehicle charging with usage constraints
(2016) Cortés, Andres; Martínez, Sonia
We present a hierarchical offline coordination algorithm for charging of Plug-in Electric Vehicles (PEVs), in which PEVs aim to optimally charge their batteries, subject to usage constraints along the day. With this algorithm, each PEV adjusts its charging strategy according to the price information, which is provided by an aggregator, while usage schedule constraints are respected at every iteration. A non-anonymous version of the algorithm is able to operate under communication failures. Both versions of the algorithm are proven to converge to the set of optimal solutions of the charging problem. This solution is optimal in the sense that it minimizes the cost of the consumed energy by both PEV and non-PEV loads. The solution has a valley-filling profile, since it leads to a configuration where PEVs aim to charge at low demand hours, minimizing, if possible, load peaks that are known to degrade the performance of power systems. In order to show convergence, we present an invariance result for difference inclusions, which works under a set of assumptions where LaSalle invariance principle does not apply. The algorithm performance is demonstrated throughout simulations.
Pasos aprendizajes sobre densificación a partir del caso español y algunas actuaciones en el sur y el norte de América
(2025-12-26) Lamíquiz-Daudén, Patxi J.; Benito-Moreno, Manuel; Carpio-Pinedo, José; Rodríguez, Daniel A.; Laboratorio de Transformación urbana
Densification understood as episodic “verticalization” has become a mainstream trend in many global capital cities, supported by expected benefits such as being an alternative to “sprawl” or strengthening urban centers by supporting a higher quality of life. This study begins from the historical link between density, proximity, and social benefits to then review the empirical evidence and examine the barriers and opportunities of select cases of densification in South and North America, areas with more dynamic urban realities than Spain. The purpose is to extract lessons applicable to Spain at a time of transition, where planning is shifting towards a greater emphasis on strategic thinking and reliance on systems of indicators and performance. The conclusions point to the need for comprehensive planning of these actions with a different emphasis: densification for urban regeneration and renodalization.
Beyond land use mix, walkable trips. An approach based on parcel-level land use data and network analysis
(2021) Carpio-Pinedo, José; Benito-Moreno, Manuel; Lamíquiz-Daudén, Patxi J.
Land use mix is one of the cornerstones for urban sustainability, in opposition to functional segregation and zoning policies. Land use mix is a prerequisite for urban proximity dynamics, healthier lifestyles and public space vitality. However, methodological shortcomings to its measurement remain and are responsible for the unexpected weak association with pedestrian activity. This study puts forward a novel method to reframe, measure and map land use mix as ‘walkable trips’, a closer approach to its benefits based on functional and spatial complementarity. The method draws on newly available cadastral microdata at the parcel-level that, combined with trip generation rates and network analysis tools, enable a detailed assessment and mapping of potential for walkable trips, as well as a proxy to the spatial patterns of urban vitality, in line with the principle of the 15-minute city. The method is applied to the case of the Madrid metropolitan area.
Proximity Features:
A Random Forest Approach to the Influence of the Built Environment on Local Travel Behavior
(2025-04) Benito-Moreno, Manuel; Carpio-Pinedo, José; Lamíquiz-Daudén, Patxi J.; Urban Transformation Laboratory
Recent European policies fostering sustainable mobility target urban proximity as a core strategy for a modal shift towards low-carbon modes. Urban proximity, as a characteristic of the built environment, can be studied as a sub-thread of a broad and complex body of literature which associates urban factors such as density or land use mix with observed travel behavior, so as to address their relative influence on the latter. Building on this previous knowledge, the present work addresses the importance of a diverse set of factors on local travel modal choice between walking and other modes, according to the 2018 Household Mobility Survey of the Metropolitan Region of Madrid, and a large variety of demographic and built environment characteristics. The work proposes to address this importance through a workflow on a set of Machine Learning models, filtering different distance thresholds and purposes of the trips, going through a strict feature selection process, and executing under different schema definitions. The resulting models are inspected for accuracy, feature importance, and composition. Results suggest that even small changes in distance thresholds exert a great impact on all models; sociodemographic variables are slightly more important in most models, yet building age, along with other street layout factors, pervasively obtain fairly accurate predictions too.
Pge production in Southern Africa, part II:
Environmental aspects
(2017-11-18) Buchspies, Benedikt; Thormann, Lisa; Mbohwa, Charles; Kaltschmitt, Martin
Platinum group elements (PGEs, 6E PGE = Pt + Pd + Rh + Ru + Ir + Au) are used in numerous applications that seek to reduce environmental impacts of mobility and energy generation. Consequently, the future demand for PGEs is predicted to increase. Previous studies indicate that environmental impacts of PGE production change over time emphasizing the need of up-to-date data and assessments. In this context, an analysis of environmental aspects of PGE production is needed to support the environmental assessment of technologies using PGEs, to reveal environmental hotspots within the production chain and to identify optimization potential. Therefore, this paper assesses greenhouse gas (GHG) emissions, cumulative fossil energy demand (CEDfossil), sulfur dioxide (SO2) emissions and water use of primary PGE production in Southern Africa, where most of today’s supply originates from. The analysis shows that in 2015, emissions amounted to 45 t CO2-eq. and 502 kg SO2 per kg 6E PGE in the case GHG and SO2 emissions, respectively. GHG emissions are dominated by emissions from electricity provision contributing more than 90% to the overall GHG emissions. The CEDfossil amounted to 0.60 TJ per kg 6E PGE. A detailed analysis of the CEDfossil reveals that electricity provision based on coal power consumes the most fossil energy carriers among all energy forms. Results show that the emissions are directly related to the electricity demand. Thus, the reduction in the electricity demand presents the major lever to reduce the consumption of fossil energy resources and the emission of GHGs and SO2. In 2015, the water withdrawal amounted to 0.272 million L per kg 6E PGE. Additionally, 0.402 million L of recycled water were used per kg 6E PGE. All assessed indicators except ore grades and production volumes reveal increasing trends in the period from 2010 to 2015. It can be concluded that difficult market conditions (see part I of this paper series) and increasing environmental impacts present a challenging situation for the Southern African PGE mining industry.
PGE production in southern Africa, part 1:
Production and market trends
(2017-11-18) Thormann, Lisa; Buchspies, Benedikt; Mbohwa, Charles; Kaltschmitt, Martin
Platinum group elements (PGEs) are an important resource for many applications, such as automotive catalytic converters for vehicles, jewelry, electrical devices and as catalysts in the chemical and petroleum industries. At present, the greatest share of global PGE supply is extracted from the South African Bushveld Complex and from the Zimbabwean Great Dyke. In this context, this article provides a comprehensive summary of detailed mining data between 2010 and 2015 and discusses these in regard to the global PGE market. On the supply side, the data reveal that the production volumes as well as the ore grades fluctuated in recent years, while the mining and processing of economically less favorable Upper Group 2 (UG2) ore increased. The average head grade from 2010 to 2015 was 3.58 g 6E/t. In the long term, the ore grades decreased. On the market side, PGE prices and increasing (primary) production costs can be observed. On the market side, the demand for vehicles is expected to grow globally resulting in an increase in PGE demand. At the same time, secondary production is expected to increase and will eventually compete with primary production. These findings indicate challenging conditions for the Southern African PGE industry.
Celiac Diasease–associated lncRNA Named HCG14 Regulates NOD1 Expression in Intestinal Cells
(2018) Santin, Izortze; Jauregi-Miguel, Amaia; Velayos, Teresa; Castellanos-Rubio, Ainara; Garcia-Etxebarria, Koldo; Romero-Garmendia, Irati; Fernandez-Jimenez, Nora; Irastorza, Iñaki; Castaño, Luis; Bilbao, Jose Ramón
Objective: The aim of the study is to identify additional celiac disease associated loci in the major histocompatibility complex (MHC) independent from classical HLA risk alleles (HLA-DR3-DQ2) and to characterize their potential functional impact in celiac disease pathogenesis at the intestinal level. Methods: We performed a high-resolution single-nucleotide polymorphism (SNP) genotyping of the MHC region, comparing HLA-DR3 homozygous celiac patients and non-celiac controls carrying a single copy of the B8-DR3-DQ2 conserved extended haplotype. Expression level of potential novel risk genes was determined by RT-PCR in intestinal biopsies and in intestinal and immune cells isolated from control and celiac individuals. Small interfering RNA-driven silencing of selected genes was performed in the intestinal cell line T84. Results: MHC genotyping revealed 2 associated SNPs, one located in TRIM27 gene and another in the non-coding gene HCG14. After stratification analysis, only HCG14 showed significant association independent from HLA-DR-DQ loci. Expression of HCG14 was slightly downregulated in epithelial cells isolated from duodenal biopsies of celiac patients, and eQTL analysis revealed that polymorphisms in HCG14 region were associated with decreased NOD1 expression in duodenal intestinal cells. Conclusions: We have successfully employed a conserved extended haplotype-matching strategy and identified a novel additional celiac disease risk variant in the lncRNA HCG14. This lncRNA seems to regulate the expression of NOD1 in an allele-specific manner. Further functional studies are needed to clarify the role of HCG14 in the regulation of gene expression and to determine the molecular mechanisms by which the risk variant in HCG14 contributes to celiac disease pathogenesis.
