Optimal railway infrastructure maintenance and repair policies to manage risk under uncertainty with adaptive control

The aim of this paper is to apply two adaptive control formulations under uncertainty, say open-loop and closed-loop, to the process of developing maintenance and repair policies for railway infrastructures. To establish the optimal maintenance and repair policies for railway lines, we use a previous design of risk model based on two factors: the criticality and the deterioration ratios of the facilities. Thus, our theory benefits from the Reliability Centered Management methodology application, but it also explicitly models uncertainty in characterizing a facility deterioration rate to decide the optimal policy to maintain the railway infrastructures. This may be the major contribution of this work. To verify the models presented, a computation study has been developed and tested for a real scenario: the railway line Villalba-Cercedilla in Madrid (Spain). Our results demonstrate again that applying any adaptive formulation, the cost of the railway lines maintenance shown is decreased. Moreover applying a Closed Loop Formulation the cost associated to the risk takes smaller values (40% less cost for the same risk than the deterministic approach), but with an Open Loop formulation the generated risk in the railway line is also smaller

OPTIMAL RAILWAY INFRASTRUCTURE MAINTENANCE AND REPAIR POLICIES TO MANAGE RISK UNDER UNCERTAINTY WITH ADAPTIVE CONTROL

The aim of this paper is to apply two adaptive control formulations under uncertainty, say open-loop and closed-loop, to the process of developing maintenance and repair policies for railway infrastructures. To establish the optimal maintenance and repair policies for railway lines, we use a previous design of risk model based on two factors: the criticality and the deterioration ratios of the facilities. Thus, our theory benefits from the Reliability Centered Management methodology application, but it also explicitly models uncertainty in characterizing a facility deterioration rate to decide the optimal policy to maintain the railway infrastructures. This may be the major contribution of this work. To verify the models presented, a computation study has been developed and tested for a real scenario: the railway line Villalba-Cercedilla in Madrid (Spain). Our results demonstrate again that applying any adaptive formulation, the cost of the railway lines maintenance shown is decreased. Moreover applying a Closed Loop Formulation the cost associated to the risk takes smaller values (40% less cost for the same risk than the deterministic approach), but with an Open Loop formulation the generated risk in the railway line is also smaller.

High-Performance low-vcc in-order core

Power density grows in new technology nodes, thus requiring Vcc to scale especially in mobile platforms where energy is critical. This paper presents a novel approach to decrease Vcc while keeping operating frequency high. Our mechanism is referred to as immediate read after write (IRAW) avoidance. We propose an implementation of the mechanism for an Intel® SilverthorneTM in-order core. Furthermore, we show that our mechanism can be adapted dynamically to provide the highest performance and lowest energy-delay product (EDP) at each Vcc level. Results show that IRAW avoidance increases operating frequency by 57% at 500mV and 99% at 400mV with negligible area and power overhead (below 1%), which translates into large speedups (48% at 500mV and 90% at 400mV) and EDP reductions (0.61 EDP at 500mV and 0.33 at 400mV).Peer ReviewedPostprint (published version

Search algorithm to find optimum strategies to shape political action with subjective assessment

This paper introduces a problem related to decision making and the shaping of political strategies in the course of one term of office, in which the government and the opposition shape their proposals for action on two issues that are relevant for the citizens. A variable component is considered regarding both the relevance of the issues to be dealt with and the strategies that the parties are presumed to adopt. The aim of this study is to find the optimum strategies for the two majority parties of a country, while allowing them to vary their proposals to a certain degree. In addition, the process is dynamic because the proposals are intended to be modified taking into account the other party’s foreseen action. The contribution of this article lies in this approach, as well as in its taking into account variable components. The problem is dealt with from a geometric point of view, and a search algorithm to find optimum strategies is developed

High Conductivity in a Fluorine-Free K-Ion Polymer Electrolyte

Solid polymer electrolytes (SPEs) could play a major role in the transition to safer and high-energy-density potassium-based batteries. However, most polymeric K-ion electrolytes are based on fluorine-containing anions and flammable organic solvents, whose safety is nowadays in question. Herein, we report a facile solvent-free synthesis of a series of several poly(ethylene oxide) (PEO)-based SPE solid solutions with KBPh4 salt as potassium-ion source, including the formation of two crystalline (PEO)$_{n}$/KBPh$_{4}$ complexes. The ionic conductivity of these novel K-ion SPEs above and below the melting point of PEO is rationalized in light of their glass-transition temperature and chemical composition. We highlight that below the melting point of PEO, the crystalline complexes may not be intrinsically ionically conducting, but they act as ion sinks preventing the polymer cross-linking and the formation of contact ion pairs and lower the glass-transition temperature leading to a conductivity of 1.1 × 10$^{-4}$ S cm$^{-1}$ at 55 °C. A high ionic conductivity of 1.8 × 10$^{-3}$ S cm$^{-1}$ is achieved at 80 °C for the optimum (PEO)$_{30}$/KBPh$_{4}$4 composition (3.2 mol % KBPh$_{4}$). Besides, the SPE compositions were found to be stable up to 4 V vs K$^{0}$ metal electrode at 60 °C. The (PEO)$_{30}$/KBPh$_{4}$ composite electrolyte employed in an all-solid-state symmetric cell with Prussian Blue electrodes showed reversible K$^{+}$-ion (de)intercalation, where a reversible capacity of 20 mAh g$^{-1}$ and low voltage hysteresis were achieved for 20 cycles. Considering the material availability, ease of synthesis, and promising electrochemical properties, this work may encourage future research on fluorine-free polymer electrolytes for K-ion batteries

Catalytic Asymmetric Synthesis of Bicycloprolines by a 1,3-Dipolar Cycloaddition/Intramolecular Alkylation Strategy

This document is the Accepted Manuscript version of a Published Work that appeared in final form inJournal of Organic Chemistry, copyright © American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see http://dx.doi.org/10.1021/acs.joc.6b01100 to Published Work, see http://pubs.acs.org/page/policy/articlesonrequest/index.htmlThe diastereoselective one-pot synthesis of hexahydrocyclopenta [b] pyrrole derivatives (bicycloprolines) has been achieved by base-mediated reactions of (E)-tert-butyl 6-bromo-2-hexenoate with α-imino esters. The catalytic asymmetric version of this process has been efficiently achieved using the CuI/(R)-DTBM-Segphos complex as a catalyst following a two-step 1,3-dipolar cycloaddition/intramolecular alkylation sequence.Financial support of this work by the Ministerio de Economía y Competitividad and Fondo Europeo de Desarrollo Regional (MINECO CTQ2012-35790 and MINECO/FEDER CTQ2015-66954-P) are gratefully acknowledged. M.G.-E. and A.P.-E. thank the MICINN for predoctoral fellowship

Compact polyelectrolyte hydrogels of gelatin and chondroitin sulfate as ion's mobile media in sustainable all-solid state electrochemical devices

The creation of flexible and high strength hydrogel materials from natural polymers aslow cost and safe solid electrolytes is an area of intense research nowadays. We presenta novel approach for the preparation of gelatin and chondroitin sulfate hydrogelscomplexes by using a simple centrifugation process. The innovative dual-bio-gelnetworkis able to swell and shrink upon environmental changes on the pH and NaClconcentration. The solid bio-gels sandwiched between two macroporous carbonelectrodes materials are assembled in symmetric cells and their electrochemicalproperties are evaluated by cyclic voltammetry, galvanostatic, and impedancespectroscopy. The cells exhibit areal capacitance values by up to 2.74 mF/cm2 (3.1 F/g)and a low resistance value of 12 Ohm.cm2 for graphene electrode materials. Theseproperties are the consequence of the successful infiltration of the solid gel inside theporous structure of the carbon electrode that boosts the charge transfer at thebiopolymer/carbon electrode interphase. The results obtained may provide additionalinspiration in the emerging field of bioelectronics, where biocompatible and poweredsystems are of the utmost importance.Fil: Gonzalez, Jimena Soledad. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones en Ciencia y Tecnología de Materiales. Universidad Nacional de Mar del Plata. Facultad de Ingeniería. Instituto de Investigaciones en Ciencia y Tecnología de Materiales; Argentina. Consejo Superior de Investigaciones Científicas; EspañaFil: Burlaka, Arsen. Consejo Superior de Investigaciones Científicas; EspañaFil: Paz, José. Consejo Superior de Investigaciones Científicas; EspañaFil: Salavagione, Horacio. Consejo Superior de Investigaciones Científicas; EspañaFil: Carretero González, Javier. Consejo Superior de Investigaciones Científicas; EspañaFil: Hernández, Rebeca. Consejo Superior de Investigaciones Científicas; Españ

Online error detection and correction of erratic bits in register files

Aggressive voltage scaling needed for low power in each new process generation causes large deviations in the threshold voltage of minimally sized devices of the 6T SRAM cell. Gate oxide scaling can cause large transient gate leakage (a trap in the gate oxide), which is known as the erratic bits phenomena. Register file protection is necessary to prevent errors from quickly spreading to different parts of the system, which may cause applications to crash or silent data corruption. This paper proposes a simple and cost-effective mechanism that increases the resiliency of the register files to erratic bits. Our mechanism detects those registers that have erratic bits, recovers from the error and quarantines the faulty register. After the quarantine period, it is able to detect whether they are fully operational with low overhead.Postprint (published version

Aneurysmal bone cyst of the mandible : case presentation and review of the literature

The aneurysmatic osseus cyst is a very infrequent bone lesion which in some occasions can be found at the craneofacial skeleton. Among all the cystic lesions that can be found at the mandible or the maxilla it is very rare. On the other side it is at the same time very interesting in terms of its differential diagnose with other types of maxillary bone lesions We present the case of a Caucasian male with an aneurysmatic cyst located at the right angle of the mandible and a review of the literature concerning the case. We have focused on the differential diagnose, mainly with the malignancies that can be found at this location. We also comment the therapeutic options clasically described for these kind of pathologies. In our patient, the surgical excision allowed a complete removal of the lesion and a posterior bone healing which made possible a implant-supported rehabilitation of the edentulous segment

Rhinoorbitocerebral mucormycosis : A case report and literature review

Mucormycosis is a rare oportunistic infection typically described in diabetic patients with a ketoacidotic status, as well as neutropenic patients. The infection is caused by a group of saprophytic fungi of the class Phycomicetes, being the most frequent ones the Rhizomucor, Rhizopus and Mucor. Its hystological findings include vascular trombosis and tissue necrosis, predominantly in the rino-orbito-cerebral area. Even though the frequency of presentation is very low, given its rapid evolution and severe consequences which include a high mortality rate, it is very important to be aware of the main features of the disease and treat it promptly. Although the diagnosis is based on the high clinical suspect, the computed tomography (CT) and the magnetic resonance image (MRI) plays an important role in determining the extension. The patients should receive treatment in a reference hospital so that a multidisciplinary approach is ensured. In this sense, we present a case of rhino-orbito-cerebralmucormycosis in a diabetic patient, recently treated in our Department. A comprehensive review of the literature has been performed to update the physiopathology and diagnosis. Finally, we describe the different treatment options focusing in the surgical approach, as well as the medical treatment with amphotericine and posaconzol