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Conceptual Model for the Replacement of the Horn of a Nineteenth Century Phonograph

  • Marín-Piñero, Beatriz
  • Madrid García, José Antonio|||0000-0002-4994-2336
  • Bachiller Martin, Maria Carmen|||0000-0002-5518-5060
[EN] 3D printing of missing parts of a cultural heritage artifact opens many possibilities and extends the challenges in the processes of intervention on cultural heritage assets. However, restoring these objects may not only mean the replacement of a missing element from its esthetic point of view, but restoring the function for which objects were created. In these processes, the replica of the object must be exact and of quality, but also specific. In this sense, the presented work is a multi-disciplinary attempt to reproduce the missing horn of a phonograph dated to the late nineteenth century. This phonograph belongs to the collection of the `Vicente Miralles Segarra¿ Telecommunication Museum of the Universitat Politècnica de València. The objective was to recover its esthetic, didactic, and functional levels, i.e restoring its ability to emit sound. To this end, several models were printed with different materials, and the quality of the recorded sound with the different horns was evaluated, assessing their similarity to that obtained from an original horn.

An advanced control strategy for biological nutrient removal in continuous systems based on pH and ORP sensors

  • Ruano, María Victoria
  • Ribes, J.
  • Seco Torrecillas, Aurora
  • Ferrer, J.|||0000-0002-1667-3854
[EN] A fuzzy logic-based control system that uses low-cost sensors for controlling and optimizing the biological nitrogen removal in continuous systems has been developed. The novelty of this control system is the use of several pH, ORP, and dissolved oxygen (DO) sensors instead of on-line nitrogen sensors/analyzers. The nitrogen control system was developed and implemented in a UCT pilot plant fed with wastewater from a full-scale plant. The developed nitrification controller allows the effluent ammonium concentration to be maintained below the effluent criteria discharge with the minimum energy consumption. The denitrification process controller allows the energy consumption derived from pumping to be minimized, as the control system only increases the internal recycle flow rate when the anoxic reactor reveals further capacity for denitrification. This advanced control strategy offers an attractive alternative to on-line, nitrogen analyzer-based control systems since it involves lower investment, maintenance, and operational costs that are derived from the instrumentation. (C) 2011 Elsevier B.V. All rights reserved., The authors would like to express their gratitude to the Ministry of Science and Education for the financial support (Project reference CTM2005-06919-C03-01/TECNO). Financial support from Entitat Publica de Sanejament d'Aigues Residuals de la Comunitat Valenciana and Depuracion de Aguas del Mediterraneo is also gratefully acknowledged.

Evaluating climate change mitigation potential of hydrochars: compounding insights from three different indicators

  • Owsianiak, Mikolaj
  • Brooks, Jennifer
  • Renz, Michael|||0000-0002-1101-9562
  • Laurent, Alexis
[EN] We employed life cycle assessment to evaluate the use of hydrochars, prospective soil conditioners produced from biowaste using hydrothermal carbonization, as an approach to improving agriculture while using carbon present in the biowaste. We considered six different crops (barley, wheat, sugar beet, fava bean, onion, and lucerne) and two different countries (Spain and Germany), and used three different indicators of climate change: global warming potential (GWP), global temperature change potential (GTP), and climate tipping potential (CTP). We found that although climate change benefits (GWP) from just sequestration and temporary storage of carbon are sufficient to outweigh impacts stemming from hydrochar production and transportation to the field, even greater benefits stem from replacing climate-inefficient biowaste management treatment options, like composting in Spain. By contrast, hydrochar addition to soil is not a good approach to improving agriculture in countries where incineration with energy recovery is the dominant treatment option for biowaste, like in Germany. Relatively small, but statistically significant differences in impact scores (ISs) were found between crops. Although these conclusions remained the same in our study, potential benefits from replacing composting were smaller in the GTP approach, which due to its long-term perspective gives less weight to short-lived greenhouse gases (GHGs) like methane. Using CTP as indicator, we also found that there is a risk of contributing to crossing of a short-term climatic target, the tipping point corresponding to an atmospheric GHG concentration of 450 ppm CO2 equivalents, unless hydrochar stability in the soil is optimized. Our results highlight the need for considering complementary perspectives that different climate change indicators offer, and overall provide a foundation for assessing climate change mitigation potential of hydrochars used in agriculture., M.O. and M.R. acknowledge the financial support of the European Commission under the Climate-KIC program; CHARM. A.L. and M.O. acknowledge financial support of European Commission under the seventh framework program; SME-2013-2: NEWAPP, grant agreement 605178.

Kaizen philosophy: The keys of the permanent suggestion systems analyzed from the workers perspective

  • Marin-Garcia, Juan A.|||0000-0001-5416-3938
  • Juárez Tárraga, Amable
  • Santandreu Mascarell, Cristina|||0000-0002-9574-9852
[EN] Purpose ¿ The purpose of this paper is to perform a context analysis about a specific Kaizen program, suggestion systems in permanent teams, and identified the barriers and facilitators that companies encounter while implementing them from the workers¿ perspective. Design/methodology/approach ¿ The authors applied an inductive method, the Grounded Theory, to develop a specific context theory using the information that emerged from a convenience sample of 182 workers in several countries. Findings ¿ The facilitators and barriers identified for the workers in the field study are aligned with those identified in previous studies, generally obtained using information provided by managers. The methodology enabled us to identify the relationships between them and their level of relevance. Research limitations/implications ¿ The main limitations were linked with the source of the data as the authors worked with a convenience sample and only analyzed the information provided by the workers. Practical implications ¿ The identified facilitators, their relationships and their relevance, contribute to understand the functioning phenomena of suggestion systems in permanent teams to facilitate organizations using this continuous improvement program more effectively. Originality/value ¿ The originality of this study, apart from identifying facilitators from the workers¿ perspective, is that the used method enabled us to identify the relationships between them and know how the operators perceived their relevance. Keywords Continuous improvement, Barriers, Kaizen, Team effectiveness, Facilitators, Grounded Theory, Suggestions systems in permanent teams

Partial Inductance Model of Induction Machines for Fault Diagnosis

  • Pineda-Sanchez, Manuel|||0000-0001-7844-8831
  • Puche-Panadero, Rubén|||0000-0003-2090-1941
  • Martinez-Roman, Javier|||0000-0001-7544-8481
  • Sapena-Bano, Angel|||0000-0002-3888-6498
  • Riera-Guasp, Martín|||0000-0003-1327-242X
  • Pérez-Cruz, Juan|||0000-0001-9718-3461
[EN] The development of advanced fault diagnostic systems for induction machines through the stator current requires accurate and fast models that can simulate the machine under faulty conditions, both in steady-state and in transient regime. These models are far more complex than the models used for healthy machines, because one of the effect of the faults is to change the winding configurations (broken bar faults, rotor asymmetries, and inter-turn short circuits) or the magnetic circuit (eccentricity and bearing faults). This produces a change of the self and mutual phase inductances, which induces in the stator currents the characteristic fault harmonics used to detect and to quantify the fault. The development of a machine model that can reflect these changes is a challenging task, which is addressed in this work with a novel approach, based on the concept of partial inductances. Instead of developing the machine model based on the phases¿ coils, it is developed using the partial inductance of a single conductor, obtained through the magnetic vector potential, and combining the partial inductances of all the conductors with a fast Fourier transform for obtaining the phases¿ inductances. The proposed method is validated using a commercial induction motor with forced broken bars, This work was supported by the Spanish "Ministerio de Economia y Competitividad" in the framework of the "Programa Estatal de Investigacion, Desarrollo e Innovacion Orientada a los Retos de la Sociedad" (project reference DPI2014-60881-R).

Estimation of privacy risk through centrality metrics

  • Alemany-Bordera, José
  • Del Val Noguera, Elena
  • Alberola Oltra, Juan Miguel
  • García-Fornes, A|||0000-0003-4482-8793
[EN] Users are not often aware of privacy risks and disclose information in online social networks. They do not consider the audience that will have access to it or the risk that the information continues to spread and may reach an unexpected audience. Moreover, not all users have the same perception of risk. To overcome these issues, we propose a Privacy Risk Score (PRS) that: (1) estimates the reachability of an user¿s sharing action based on the distance between the user and the potential audience; (2) is described in levels to adjust to the risk perception of individuals; (3) does not require the explicit interaction of individuals since it considers information flows; and (4) can be approximated by centrality metrics for scenarios where there is no access to data about information flows. In this case, if there is access to the network structure, the results show that global metrics such as closeness have a high degree of correlation with PRS. Otherwise, local and social centrality metrics based on ego-networks provide a suitable approximation to PRS. The results in real social networks confirm that local and social centrality metrics based on degree perform well in estimating the privacy risk of users., This work is partially supported by the Spanish Government project TIN2014-55206-R and FPI grant BES-2015-074498.

A hypercyclicity criterion for non-metrizable topological vector spaces

  • Peris Manguillot, Alfredo|||0000-0003-1683-2373
[EN] We provide a sufficient condition for an operator T on a non-metrizable and sequentially separable topological vector space X to be sequentially hypercyclic. This condition is applied to some particular examples, namely, a composition operator on the space of real analytic functions on ]0; 1[, which solves two problems of Bonet and Domanski [3], and the ¿snake shift¿ constructed in [5] on direct sums of sequence spaces. The two examples have in common that they do not admit a densely embedded F-space Y for which the operator restricted to Y is continuous and hypercyclic, i.e., the hypercyclicity of these operators cannot be a consequence of the comparison principle with hypercyclic operators on F-spaces., The author thanks Jose Bonet and Pawel Domanski for interesting conversations on the results of the paper, and the referee for valuable comments that produced an improved presentation. He also acknowledges the support of MINECO, Project MTM2016-75963-P, and Generalitat Valenciana, Project PROMETEO/2017/102.

The mathematical work of Pawel Domanski

  • Bonet Solves, José Antonio|||0000-0002-9096-6380
  • Langenbruch, Michael
[EN] We report on the mathematical work of Pawel Domanski (AMU Poznan)., The authors are very grateful to their colleagues in Poznan for their help in the preparation of this paper and for the translation to Polish. Bonet wants to thank the Alexander von Humboldt Foundation for the support. This article was prepared during a stay of him in Germany partially supported by AvH.

Nitric Oxide Controls Constitutive Freezing Tolerance in Arabidopsis by Attenuating the Levels of Osmoprotectants, Stress-Related Hormones and Anthocyanins

  • Costa-Broseta, Álvaro
  • Perea-Resa, Carlos
  • Castillo López Del Toro, Mª Cruz
  • Ruíz, M. Fernanda
  • Salinas, Julio
[EN] Plant tolerance to freezing temperatures is governed by endogenous constitutive components and environmental inducing factors. Nitric oxide (NO) is one of the endogenous components that participate in freezing tolerance regulation. A combined metabolomic and transcriptomic characterization of NO-deficient nia1,2noa1¿2 mutant plants suggests that NO acts attenuating the production and accumulation of osmoprotective and regulatory metabolites, such as sugars and polyamines, stress-related hormones, such as ABA and jasmonates, and antioxidants, such as anthocyanins and flavonoids. Accordingly, NO-deficient plants are constitutively more freezing tolerant than wild type plants., This work was supported by grants BIO2011-27526 and BIO2014-56067-P from the Spanish Ministry of Economy and Competitiveness and FEDER funds. We thank support and comments from Janice Jones and Danny Alexander (Metabolon Inc., USA) on metabolomic analyses.

Design and Validation of an FPGA-Based Configurable Transcranial Doppler Neurofeedback System for Chronic Pain Patients

  • Rey, Beatriz|||0000-0001-9213-1443
  • Rodriguez Ortega, Alejandro
  • Herrero Bosch, Vicente|||0000-0003-0860-2789
  • Monzó Ferrer, José María
[EN] Neurofeedback is a self-regulation technique that can be applied to learn to voluntarily control cerebral activity in specific brain regions. In this work, a Transcranial Doppler-based configurable neurofeedback system is proposed and described. The hardware configuration is based on the Red Pitaya board, which gives great flexibility and processing power to the system. The parameter to be trained can be selected between several temporal, spectral, or complexity features from the cerebral blood flow velocity signal in different vessels. As previous studies have found alterations in these parameters in chronic pain patients, the system could be applied to help them to voluntarily control these parameters. Two protocols based on different temporal lengths of the training periods have been proposed and tested with six healthy subjects that were randomly assigned to one of the protocols at the beginning of the procedure. For the purposes of the testing, the trained parameter was the mean cerebral blood flow velocity in the aggregated data from the two anterior cerebral arteries. Results show that, using the proposed neurofeedback system, the two groups of healthy volunteers can learn to self-regulate a parameter from their brain activity in a reduced number of training sessions., This research was funded by Ministerio de Economia y Competitividad, Spain, grant number PSI2013-48260-C3-2-R. The APC was funded by Ministerio de Economia y Competitividad, Spain, grant number PSI2013-48260-C3-2-R.

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