SEMI-EMPIRICAL METHOD FOR DESIGNING EXCAVATION SUPPORT SYSTEMS BASED ON DEFORMATION CONTROL

Due to space limitations in urban areas, underground construction has become a common practice worldwide. When using deep excavations, excessive lateral movements are a major concern because they can lead to significant displacements and rotations in adjacent structures. Therefore, accurate predictions of lateral wall deflections and surface settlements are important design criteria in the analysis and design of excavation support systems. This research shows that the current design methods, based on plane strain analyses, are not accurate for designing excavation support systems and that fully three-dimensional (3D) analyses including wall installation effects are needed. A complete 3D finite element simulation of the wall installation at the Chicago and State Street excavation case history is carried out to show the effects of modeling: (i) the installation sequence of the supporting wall, (ii) the excavation method for the wall, and (iii) existing adjacent infrastructure. This model is the starting point of a series of parametric analyses that show the effects of the system stiffness on the resulting excavation-related ground movements. Furthermore, a deformation-based methodology for the analysis and design of excavation support systems is proposed in order to guide the engineer in the different stages of the design. The methodology is condensed in comprehensive flow charts that allow the designer to size the wall and supports, given the allowable soil distortion of adjacent structures or predict ground movements, given data about the soil and support system

Dynamics of Price Adjustments: Evidence From Micro Level Data For Chile

This paper characterizes the dynamics of price adjustments in Chile using data at the establishment level of goods in the CPI basket. Our results show that nominal rigidities are lower when measured at micro-level compared to estimates based on macro data. The frequency of price adjustments appears to be relatively stable over the sample period 1999-2005. On the other hand, if we decompose price adjustments in upward and downward changes, we observe that these frequencies of adjustments for some groups of products are correlated with the level of aggregate inflation. Thus, the data shows that the intensive and extensive margins of price adjustment play a role in determining price dynamics. Finally, we find a considerable degree of synchronization in price adjustments across establishments and a moderate increase in price dispersion since 1999.

Two-week joint mobilization intervention improves self-reported function, range of motion, and dynamic balance in those with chronic ankle instability

We examined the effect of a 2-week anterior-to-posterior ankle joint mobilization intervention on weight-bearing dorsiflexion range of motion (ROM), dynamic balance, and self-reported function in subjects with chronic ankle instability (CAI). In this prospective cohort study, subjects received six Maitland Grade III anterior-to-posterior joint mobilization treatments over 2 weeks. Weightbearing dorsiflexion ROM, the anterior, posteromedial, and posterolateral reach directions of the Star Excursion Balance Test (SEBT), and self-reported function on the Foot and Ankle Ability Measure (FAAM) were assessed 1 week before the intervention (baseline), prior to the first treatment (pre-intervention), 24–48 h following the final treatment (post-intervention), and 1 week later (1-week follow-up) in 12 adults (6 males and 6 females) with CAI. The results indicate that dorsiflexion ROM, reach distance in all directions of the SEBT, and the FAAM improved (p < 0.05 for all) in all measures following the intervention compared to those prior to the intervention. No differences were observed in any assessments between the baseline and pre-intervention measures or between the postintervention and 1-week follow-up measures (p > 0.05). These results indicate that the joint mobilization intervention that targeted posterior talar glide was able to improve measures of function in adults with CAI for at least 1 week

Hacia un proceso de migración de la seguridad de sistemas heredados al Cloud

El desarrollo de la computación en la nube es una tendencia fuerte en la industria de las TI que hace que los clientes de este nuevo modelo de prestación de servicios, sobre todo las empresas, se enfrenten a desafíos nuevos en lo que se refiere a la gestión de la seguridad de sus aplicaciones heredadas en el nuevo entorno. La cuestión es en cómo migrar de forma segura los sistemas de información heredados de estas empresas. Este artículo presenta un proceso (SMiLe2Cloud) y un marco de trabajo con el que se puede migrar de forma segura los sistemas corporativos heredados a infraestructuras o entornos en la nube, siguiendo los 14 dominios de seguridad del CSA y utilizando ingeniería inversa.Esta investigación es parte de los siguientes proyectos: GEODAS (TIN2012-37493-C03-01) y SIGMA-CC (TIN2012-36904) financiados por el “Ministerio de Economía y Competitividad y Fondo Europeo de Desarrollo Regional FEDER”, España

Stated preferences for anti-malarial drug characteristics in Zomba, a malaria endemic area of Malawi

Background The evidence on determinants of individuals’ choices for anti-malarial drug treatments is scarce. This study sought to measure the strength of preference for adult antimalarial drug treatment attributes of heads of urban, rural and peri-urban households in a resource-limited malaria-endemic area of sub-Saharan Africa. Methods Discrete choice experiments were conducted with 508 heads of household interviewed face-to-face for a household population survey of health-seeking behavior in Zomba District, Malawi. The interviews were held in Chichewa and the choice experiment questions were presented with cartoon aids. The anti-malarial drug attributes included in the stated preference experiment were: speed of fever resolution, side effects (pruritus) risk, protection (duration of prophylactic effect), price, duration of treatment course and recommendation by a health professional. Sixteen treatment profiles from a fractional factorial design by orthogonal array were paired into choice scenarios, and scenarios were randomly assigned to participants so that each participant was presented with a series of eight pairwise choice scenarios. Respondents had the option to state indifference between the two profiles or decline to choose. Data were analysed in a mixed logit model, with normally distributed coefficients for all six attributes. Results The sex ratio was balanced in urban areas, whereas 63% of participants in rural areas were male. The proportion of individuals with no education was considerably higher in the rural group (25%) than in the urban (5%) and peri-urban (6%) groups. All attributes investigated had the expected influence, and traded-off in most respondents’ choices. There were heterogeneous effects of price, pruritus risk, treatment recommendation by a professional, and duration of prophylaxis across respondents, only partly explained by their differences in education, household per capita expenditure, sex and age. Individuals´ demand elasticity (simulated median, inter-quartile range) was highest (most responsive) to speed of symptom resolution (0.88, 0.80-0.89) and pruritus risk (0.25, 0.08-0.62). Conclusions Most adult antimalarial users are willing to use treatments without recommendation from health professional, and may be influenced by price. Future studies should investigate the magnitude of differences in price and treatment attribute sensitivity between adult anti-malarial drug users in rural, peri-urban and urban areas in order to determine optimal price subsidies

GFET Asymmetric Transfer Response Analysis through Access Region Resistances

Graphene-based devices are planned to augment the functionality of Si and III-V based technology in radio-frequency (RF) electronics. The expectations in designing graphene field-effect transistors (GFETs) with enhanced RF performance have attracted significant experimental efforts, mainly concentrated on achieving high mobility samples. However, little attention has been paid, so far, to the role of the access regions in these devices. Here, we analyse in detail, via numerical simulations, how the GFET transfer response is severely impacted by these regions, showing that they play a significant role in the asymmetric saturated behaviour commonly observed in GFETs. We also investigate how the modulation of the access region conductivity (i.e., by the influence of a back gate) and the presence of imperfections in the graphene layer (e.g., charge puddles) affects the transfer response. The analysis is extended to assess the application of GFETs for RF applications, by evaluating their cut-off frequency.This research was founded by Spanish government grant numbers TEC2017-89955-P (MINECO/AEI/FEDER, UE), TEC2015-67462-C2-1-R (MINECO), IJCI-2017-32297 (MINECO/AEI), FPU16/04043 and FPU14/02579, and the European Union’s Horizon 2020 Research and Innovation Program under Grant GrapheneCore2 785219

La Seguridad como una asignatura indispensable para un Ingeniero del Software

La seguridad informática ha venido cobrando mayor importancia para las organizaciones dado el marcado crecimiento de las nuevas tecnologías de la información, servicios Web, comercio electrónico, etc. Es por ello que existe la necesidad de contar con nuevos profesionales en este entorno. Para ello, es necesario contar con asignaturas de Seguridad en las escuelas universitarias, que doten al futuro profesional de los conocimientos necesarios para afrontar con éxito las necesidades que el mundo empresarial actual demanda. Así, aprovechando el estado actual de implantación del sistema europeo de créditos, en este artículo se resume una propuesta de grado de informática, y se presenta la asignatura de Seguridad de Sistemas Software, ubicada en el perfil de Ingeniería del Software, definiendo el contenido de dicha asignatura de acuerdo a las directrices del sistema ECTS, y a las necesidades reales que cualquier ingeniero del software puede encontrarse en el mundo empresarial actual.Peer Reviewe

Métricas para la medición de las competencias generales y específicas para el Grado en Ingeniería Informática

El proceso de elaboración de las memorias de grado se ha basado en un conjunto de competencias generales y específicas que, en la mayoría de los casos, entrañan un alto nivel de abstracción y ambigüedad. Por otro lado, la aparición de las competencias no ha ayudado a los alumnos a entender mejor en qué medida alcanzan los objetivos de las diferentes asignaturas, ni a tomar mejores decisiones sobre los pasos a seguir en su carrera profesional. En este artículo se pretende mostrar los resultados obtenidos durante la investigación realizada, que ha tenido como objetivo desgranar las competencias generales y específicas del Grado en Ingeniería Informática, de modo que se ofrezca un acercamiento mucho más concreto y detallado con las asignaturas y, consecuentemente, que pueda justificarse adecuadamente la forma en que las asignaturas permiten alcanzar parcial o completamente las competencias para el grado. Este enfoque, y su orientación a obtener métricas sobre las que valorar el grado en que se han alcanzado los objetivos, también permitirá que los alumnos puedan tomar mejores decisiones a la hora de seleccionar las diferentes asignaturas del grado y conocer para qué competencias están mejor cualificados.SUMMARY -- The process of writing honours theses is based on a set of general and specific competences which, in the majority of cases, entail a high level of abstraction and ambiguity. What is more, the apparition of these competences has not helped students towards a better understanding of the extent to which they attain the objectives of their various subjects, or to make better decisions as regards the steps to follow in their professional careers. The intention of this paper is to show the results obtained during research whose objective was to separate the general and specific competences involved in the Computer Engineering Degree in order to provide a much more concrete and detailed approach to the subjects, which will consequently allow the way in which the subjects permit the partial or total attainment of the competences for the degree to be justified. This approach, and its orientation towards obtaining metrics with which to evaluate the degree to which the objectives have been attained, will also allow students to make better decisions when selecting various degree subjects and to discover for which competences they are best qualified.Peer Reviewe

Active Stars in the Spectroscopic Survey of Mid-to-Late M Dwarfs Within 15pc

We present results from the volume-complete spectroscopic survey of 0.1-0.3M$_\odot$ M dwarfs within 15pc. This work discusses the active sample without close binary companions, providing a comprehensive picture of these 123 stars with H${\alpha}$ emission stronger than -1\unicode{xC5}. Our analysis includes rotation periods (including 31 new measurements), H${\alpha}$ equivalent widths, rotational broadening, inclinations, and radial velocities, determined using high-resolution, multi-epoch spectroscopic data from the TRES and CHIRON spectrographs supplemented by photometry from TESS and MEarth. Using this volume-complete sample, we establish that the majority of active, low-mass M dwarfs are very rapid rotators: specifically, 74$\pm$4% have rotation periods shorter than 2 days, while 19$\pm$4% have intermediate rotation periods of 2-20 days, and the remaining 8$\pm$3% have periods longer than 20 days. Among the latter group, we identify a population of stars with very high H${\alpha}$ emission, which we suggest is indicative of dramatic spindown as these stars transition from the rapidly to slowly rotating modes. We are unable to determine rotation periods for six stars and suggest that some of the stars without measured rotation periods may be viewed pole-on, as such stars are absent from the distribution of inclinations we measure; this lack notwithstanding, we recover the expected isotropic distribution of spin axes. Our spectroscopic and photometric data sets also allow us to investigate activity-induced radial-velocity variability, which we show can be estimated as the product of rotational broadening and the photometric amplitude of spot modulation.Comment: Accepted for publication in AJ; 18 pages, 12 figures, 3 table