Short- and long-term analytical solutions for composite beams with partial interaction and shear-lag effects

This paper presents an analytical model for the short- and long-term analysis of composite steel-concrete beams with partial shear interaction and accounting for shear-lag effects. The material properties of the concrete have been assumed to be time-dependent and have been modelled by means of the algebraic methods while the remaining materials forming the cross-section have been supposed to behave in a linear-elastic manner. The global balance condition of the problem has been obtained by means of the principle of virtual work and, integrating this by parts, the governing system of differential equations and corresponding boundary conditions have been determined. Analytical expressions for both short- and long-term solutions have been derived and, to outline their ease of use, a number of case studies relevant for bridge applications have been proposed.     

Environmental Assessment of Sewer Construction in Small to Medium Sized Cities Using Life Cycle Assessment

In a world with an increasing urban population, analysing the construction impacts of sanitation infrastructures through Life Cycle Assessment (LCA) is necessary for defining the best environmental management strategies. In this study, the environmental impacts of one linear meter of sewer constructive solution were analysed for different pipe materials and diameters used in Southern Europe; a unit of different sewer appurtenances (pump, manhole and inspection chamber) was also considered. The impacts of the pipe materials were compared considering different lifespan periods and high-density polyethylene (HDPE) turned out to be the worst option, being polyvinyl chloride (PVC) and concrete the most favourable ones. Few data are available on the material and energy flows in the installation stage; therefore, a comparative analysis of trenches with sand and concrete bedding was conducted. The results show that the installation stage represents up to 80 % of the total life-cycle impact of the constructive solutions. Concrete pipes with half-concrete/half-sand bedding are the best option and produce 20–30 % of the impact of HDPE pipes with concrete bedding. Hence, designers should focus not only on the pipe but also on the trench model. A methodology was presented to enable the impact aggregation of the different sewer elements, and Betanzos (Spain) was selected to conduct a pilot study in small cities. In the future, studies will need to incorporate the use and maintenance stage, as it is not standard and varies according to the physical features of the cities. Finally, this study provides basic concepts for developing eco-efficiency indicators.     

Self-structure in schizophrenia.

This study used a set-theoretical model to construct self-perception structures and person-perception structures for 10 recently hospitalized schizophrenic patients, 10 nonschizophrenic patients recently hospitalized for depression, and 10 nonpsychiatric subjects. Overall self-perception structures were significantly less elaborated in the schizophrenic patients when compared with either the psychiatric or the nonpsychiatric comparison group. No comparable differences were found for measures taken from the person-perception structures. The degree of elaboration of self in the particular context of self as psychiatric patient was found to be correlated (r?=?.74, p     

Self-complexity, self-evaluation, and depression: An examination of form and content within the self-schema.

Six studies examined the relationship between self-complexity and variables related to self-evaluation. Self-complexity was found to comprise two components: positive self-complexity and negative self-complexity. Positive self-complexity was sensitive to methodological factors, namely, variations in stimulus materials used for self-ratings. Negative self-complexity was relatively stable in the face of different rating stimuli and tasks and was related to trait measures of self-evaluation, psychic distress, and psychopathology. These findings were observed and replicated. Higher negative self-complexity was associated with increases in depression symptoms over time. Higher negative self-complexity also predicted a poorer prognosis and less complete recovery from depression in a clinical sample. Results are discussed in light of related research and possible social–cognitive mechanisms. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Exploiting Workload Parallelism for Performance and Power Optimization in Blue Gene

Optimizing future supercomputing applications will depend on delivering the best performance for a given power budget. To determine the effect on efficiency of application-scaling parameters, this article analyzes system power and performance measurement results for real-world applications exploiting thread- and data-level parallelism on the Blue Gene/L system     

Influence of an increased NaCl concentration on yield and quality of cherry tomato grown in posidonia (Posidonia oceanica (L) Delile)

Tomato plants cv Naomi were grown in posidonia (Posidonia oceanica (L) Delile) with two NaCl salinity levels in nutrient solution (EC: 3 and 6 dS m^?1) or with the NaCl level 3 dS m^?1, in the most frequently used substrate in soilless systems, eg rockwool, to determine the effect of substrate or EC on yield, contents of minerals, antioxidants with nutritional and health values (vitamin C, lycopene, α‐tocopherol and glutathione) as well as parameters affecting the organoleptic quality in cherry tomato fruits. Total yield was not influenced by substrate, but it was higher with 3 dS m^?1 than 6 dS m^?1 salinity. The yield reduction was compensated by the improvement of dry matter, total soluble solids, vitamin C and α‐tocopherol, while lycopene and glutathione contents were not affected by NaCl. On average, when tomato plants were grown in the presence of the higher NaCl level, the fruit diameter was between 25 and 35 mm (considered optimal for cherry tomato) while, with 3 dS m^?1, it was greater than 35 mm. Copyright © 2004 Society of Chemical Industry     

Reducing total annualized cost and CO2 emissions in batch distillation: Dynamics and control

In this contribution, the direct vapor recompression approach is introduced in a batch distillation operated at an unsteady state condition. This vapor recompressed batch distillation (VRBD) accompanies an isentropic compressor that runs at a fixed as well as variable speed. Aiming to ensure the optimal use of internal heat source, an open‐loop control policy is proposed for the VRBD that adjusts either the overhead vapor splitting or the external heat supply to the reboiler. Again, the variable speed VRBD additionally involves the manipulation of compression ratio. Developing two alternative configurations of VRBD column, the best heat integrated scheme is attempted to identify in the aspects of energy efficiency and total annualized cost for further advancement. A closed‐loop control algorithm for the best performing variable speed VRBD aiming to meet the end objective of relatively high‐purity product discharged at a constant composition is developed. The separation of a reactive system is considered to illustrate these results and demonstrate the effectiveness of the novel VRBD scheme. Performing simulation tests, it is investigated that the closed‐loop control operation substantially improves not only the distillate purity but also the total amount of product. Achieving significant improvement in thermodynamic efficiency and cost by the controlled heat integrated scheme over its conventional counterpart, finally the attractiveness of the VRBD column by investigating its potential to reduce the greenhouse gas (i.e., CO₂) emissions is shown. © 2013 American Institute of Chemical Engineers AIChE J, 59: 2821–2832, 2013