Robustness evaluation of seismic pile response considering uncertainty mechanism of soil properties

Robustness analysis of the seismic pile response of a structure–pile–soil system with uncertain soil properties and concrete Young’s modulus is presented in this paper. The bounds of the bending moment of a pile are investigated by means of the previously proposed uncertainty analysis method (Updated Reference-Point method) and the newly developed revised method (NURP method). An efficient finite-element model of a structure–pile–soil system with smart displacement functions for connecting elements is adopted and a response spectrum method is applied in the evaluation of the seismic pile responses of the system. Two cases of soil uncertainties resulting from different uncertainty mechanisms are considered. It is shown that the worst combination of uncertain soil parameters can be determined by the NURP method in an accurate manner

Simulations of a Variable Friction Device for Multihazard Mitigation

This paper investigates the performance of a novel semiactive damping device at mitigating nonsimultaneous multihazard loads. The device, termed modified friction device (MFD), has been previously proposed by the authors. It consists of a variable friction system based on automotive drum brake technology. The device has been demonstrated in a laboratory environment, and its dynamic behavior has been modeled. This model is used to conduct numerical simulations on two representative structures, one short building located in Japan and the other tall building located in Boston, MA. Simulated hazards include wind, blast, and seismic loads. Various control cases are considered, including semiactive control under five different sets of control weights, and passive viscous and passive friction to benchmark performance. Results show that the semiactive control cases outperforms all of the other cases for the vast majority of hazards and performance indices, provided that the right control weights are utilized

Fail-safe optimization of viscous dampers for seismic retrofitting

This paper presents a new optimization approach for designing minimum-cost fail-safe distributions of fluid viscous dampers for seismic retrofitting. Failure is modeled as either complete damage of the dampers or partial degradation of the dampers' properties. In general, this leads to optimization problems with large number of constraints. Thus, the use of a working-set optimization algorithm is proposed. The main idea is to solve a sequence of relaxed optimization sub-problems with a small sub-set of all constraints. The algorithm terminates once a solution of a sub-problem is found that satisfies all the constraints of the problem. The retrofitting cost is minimized with constraints on the inter-story drifts at the peripheries of frame structures. The structures considered are subjected to a realistic ensemble of ground motions, and their response is evaluated with time-history analyses. The transient optimization problem is efficiently solved with a gradient-based sequential linear programming algorithm. The gradients of the response functions are calculated with a consistent adjoint sensitivity analysis procedure. Promising results attained for 3-D irregular frames are presented and discussed. The numerical results highlight the fact that the optimized layout and size of the dampers can change significantly even for moderate levels of damage

A practical method for optimum seismic design of friction wall dampers

Friction control systems have been widely used as one of the efficient and cost effective solutions to control structural damage during strong earthquakes. However, the height-wise distribution of slip loads can significantly affect the seismic performance of the strengthened frames. In this study, a practical design methodology is developed for more efficient design of friction wall dampers by performing extensive nonlinear dynamic analyses on 3, 5, 10, 15, and 20-story RC frames subjected to seven spectrum-compatible design earthquakes and five different slip load distribution patterns. The results show that a uniform cumulative distribution can provide considerably higher energy dissipation capacity than the commonly used uniform slip load pattern. It is also proved that for a set of design earthquakes, there is an optimum range for slip loads that is a function of number of stories. Based on the results of this study, an empirical equation is proposed to calculate a more efficient slip load distribution of friction wall dampers for practical applications. The efficiency of the proposed method is demonstrated through several design examples

Strategies from Dramatherapy supervision to augment newly qualified secondary school teachers' experience of self-efficacy and coping strategies in their new role

This study aims to investigate if strategies from Dramatherapy supervision can augment newly qualified teachers’ (NQTs) experience of self-efficacy and coping strategies in their new role. This research study sets out to explore the growing necessity for a more specific form of reflective practice for two separate cohorts of NQTs n =10 (per group) over the course of two consecutive academic years. According to recent research, teacher turnover is more prevalent in disadvantaged urban schools as a result of contextual factors: ‘an increasing workload’, ‘school situation’, the ‘turbulent student-teacher classroom dynamics’, as well as the ‘conflicting agendas between teachers and educational reform’. The study’s theoretical framework draws from teacher education, psychodynamic theory and Dramatherapy supervision theory and practice, to help NQTs develop coping pathways for self-exploration and personal growth, to obtain an increased awareness of the social and emotional processes involved in teaching and learning and to manage both individual and contextual factors that influence their sense of efficacy in their new role as a teacher. The study uses mixed methods to ascertain the efficacy of strategies from Dramatherapy supervision. Quantitative outcome measures are employed to ascertain overall self-efficacy, coping strategies and job satisfaction. Interpretative phenomenological Analyses is used to analyse the qualitative findings amassed from the post-intervention interviews with the NQTs. Autoethnography is employed to bracket the researcher’s personal reflections on the fieldnotes and to study the process of change over time in three case studies, in relation to the NQTs’ sense of efficacy and coping skills. Conclusions drawn from the results highlight that methods from Dramatherapy supervision can be beneficial for developing NQTs’ self-awareness, deepening their understanding of the challenging interpersonal dynamics and providing them with a reflective ‘meditative’ space created through creative techniques. However, the success of these findings is dependent on a number of internal and external variables that influence the NQTs’ sense of efficacy. Recommendations for education include: addressing the impact that the target driven educational climate has on the emotional well-being of teachers and subsequently their pupils, implementing compulsory regular group reflection into teacher practice based on the intervention of ‘strategies from Dramatherapy supervision’ with particular focus on mode 2 of the double matrix model of supervision and embedding training in school communities about and how to be in relationships

Combining blue native polyacrylamide gel electrophoresis with liquid chromatography tandem mass spectrometry as an effective strategy for analyzing potential membrane protein complexes of Mycobacterium bovis bacillus Calmette-Guérin

<p>Abstract</p> <p>Background</p> <p>Tuberculosis is an infectious bacterial disease in humans caused primarily by <it>Mycobacterium tuberculosis</it>, and infects one-third of the world's total population. <it>Mycobacterium bovis </it>bacillus Calmette-Guérin (BCG) vaccine has been widely used to prevent tuberculosis worldwide since 1921. Membrane proteins play important roles in various cellular processes, and the protein-protein interactions involved in these processes may provide further information about molecular organization and cellular pathways. However, membrane proteins are notoriously under-represented by traditional two-dimensional polyacrylamide gel electrophoresis (2-D PAGE) and little is known about mycobacterial membrane and membrane-associated protein complexes. Here we investigated <it>M. bovis </it>BCG by an alternative proteomic strategy coupling blue native PAGE to liquid chromatography tandem mass spectrometry (LC-MS/MS) to characterize potential protein-protein interactions in membrane fractions.</p> <p>Results</p> <p>Using this approach, we analyzed native molecular composition of protein complexes in BCG membrane fractions. As a result, 40 proteins (including 12 integral membrane proteins), which were organized in 9 different gel bands, were unambiguous identified. The proteins identified have been experimentally confirmed using 2-D SDS PAGE. We identified MmpL8 and four neighboring proteins that were involved in lipid transport complexes, and all subunits of ATP synthase complex in their monomeric states. Two phenolpthiocerol synthases and three arabinosyltransferases belonging to individual operons were obtained in different gel bands. Furthermore, two giant multifunctional enzymes, Pks7 and Pks8, and four mycobacterial Hsp family members were determined. Additionally, seven ribosomal proteins involved in polyribosome complex and two subunits of the succinate dehydrogenase complex were also found. Notablely, some proteins with high hydrophobicity or multiple transmembrane helixes were identified well in our work.</p> <p>Conclusions</p> <p>In this study, we utilized LC-MS/MS in combination with blue native PAGE to characterize modular components of multiprotein complexes in BCG membrane fractions. The results demonstrated that the proteomic strategy was a reliable and reproducible tool for analysis of BCG multiprotein complexes. The identification in our study may provide some evidence for further study of BCG protein interaction.</p

Metal-Substituted Microporous Aluminophosphates

This chapter aims to present the zeotypes aluminophosphates (AlPOs) as a complementary alternative to zeolites in the isomorphic incorporation of metal ions within all-inorganic microporous frameworks as well as to discuss didactically the catalytic consequences derived from the distinctive features of both frameworks. It does not intend to be a compilation of either all or the most significant publications involving metal-substituted microporous aluminophosphates. Families of AlPOs and zeolites, which include metal ion-substituted variants, are the dominant microporous materials. Both these systems are widely used as catalysts, in particular through aliovalent metal ions substitution. Here, some general description of the synthesis procedures and characterization techniques of the MeAPOs (metal-contained aluminophosphates) is given along with catalytic properties. Next, some illustrative examples of the catalytic possibilities of MeAPOs as catalysts in the transformation of the organic molecules are given. The oxidation of the hardly activated hydrocarbons has probably been the most successful use of AlPOs doped with the divalent transition metal ions Co2+, Mn2+, and Fe2+, whose incorporation in zeolites is disfavoured. The catalytic role of these MeAPOs is rationalized based on the knowledge acquired from a combination of the most advanced characterization techniques. Finally, the importance of the high specificity of the structure-directing agents employed in the preparation of MeAPOs is discussed taking N,N-methyldicyclohexylamine in the synthesis of AFI-structured materials as a driving force. It is shown how such a high specificity could be predicted and how it can open great possibilities in the control of parameters as critical in catalysis as crystal size, inter-and intracrystalline mesoporosity, acidity, redox properties, incorporation of a great variety of heteroatom ions or final environment of the metal site (surrounding it by either P or Al)