One-shot methods in function space for PDE-constrained optimal control problems

We state and analyse one-shot methods in function space for the optimal control of nonlinear partial differential equations (PDEs) that can be formulated in terms of a fixed-point operator. A general convergence theorem is proved by generalizing the previously obtained results in finite dimensions. As application examples we consider two nonlinear elliptic model problems: the stationary solid fuel ignition model and the stationary viscous Burgers equation. For these problems we present a more detailed convergence analysis of the method. The resulting algorithms are computationally implemented in combination with an adaptive mesh refinement strategy, which leads to an improvement in the performance of the one-shot approach.     

RF/wireless-interconnect: The next wave of connectivity

In the era of the nanometer CMOS technology, due to stringent system requirements in power, performance and other fundamental physical limitations (such as mechanical reliability, thermal constraints, overall system form factor, etc.), future VLSI systems are relying more on ultra-high data rates (up to 100 Gbps/pin or 20 Tbps aggregate), scalable, re-configurable, highly compact and reliable interconnect fabric. To overcome such challenges, we first explore the use of multiband RF/wireless-interconnects wh...     

A Box–Behnken Design-Based Model for Predicting Power Performance in Microbial Fuel Cells Using Wastewater

Although modeling is regarded as a useful tool to understand the performance of microbial fuel cells (MFCs), the number of MFC models remains very low compared with the number of experimental works available in the literature. Moreover, there are very few MFC modeling attempts dealing with the use of wastewater as fuel in these devices, which is essential for the practical implementation of MFCs since the potential of this technology lies in the two-fold benefit of wastewater treatment and bioenergy generation. In this work, a four-factor three-level Box–Behnken design was developed to model the electrochemical power generation in two-chamber MFCs using wastewater as fuel. The optimum values of temperature, external resistance, feed concentration and anodic pH that maximized power output were investigated. Optimum conditions were found at T = 35°C and R = 1 kΩ, corresponding to a maximum power density of 0.88 W·m^?3, while feed concentration and pH did not show statistical significance in the ranges studied. Thus, a Box–Behnken design-based model as empirical approach could provide an effective tool for the optimization study of MFC systems.     

In vitro injury model for oligodendrocytes: development, injury, and recovery

In this study we investigated the effects of severe hypothermia (cryoinjury) on oligodendrocyte (OL) cell marker expression and morphological features. We used a chemically defined cell culture medium, glial development medium (GDM), which favored the optimal expression of the OL phenotype in CG4 cells. Experiments using CG4 cells cultured in 2% serum or in GDM were conducted in parallel. After severe hypothermia, cells were reanimated at 37 degrees C and 4.5% CO(2) and cultured in either GDM or in medium supplemented with 2% serum. In either medium, around 70% of the total number of cells detached within 2 to 4 hours following reanimation. Oligodendroglial markers such as A2B5, O4, Tf, ferritin, tubulin, and MBP were examined by double and triple immunofluorescence. All of these markers except MBP re-appeared at different times during the recovery period for up to 48 hours. Glial fibrillary acidic protein (GFAP) and heat shock protein 60 (HSP-60) were used as injury markers. The presence of serum induced HSP-60 expression, while GDM did not. All CG4 cells expressed HSP-60 in response to hypothermia independently of the cell culture medium used. Cryoinjury induced a spectrum of morphological changes in CG4 cells. The expression of OL specific markers was also influenced by hypothermia. Moreover both, serum and cryoinjury induced the expression of HSP-60 that colocalized with OL and myelin markers. The expression of GFAP by injured cells but not by normal cells corroborated the state of injury of CG4 cells.     

Intentional and unintentional contributions of nonspecific preparation during reaction time foreperiods.

The nonspecific preparation that follows a warning stimulus (WS) to speed responding to an impending imperative stimulus (IS) is generally viewed as a strategic, intentional process. An alternative view holds that WS acts as a conditioned stimulus that unintentionally elicits a tendency to respond at the moment of IS presentation as a result of a process of trace conditioning. These views were contrasted as explanatory frameworks for classical effects on reaction time of the duration and intertrial variability of the foreperiod, the interval between WS and IS. It is shown that the conditioning view accounts for the available data at least as well as the strategic view. In addition, the results of 3 experiments provide support for the conditioning view by showing that unintentional contributions to nonspecific preparation can be dissociated from intentional contributions. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Measuring Water Affordability: A Proposal for Urban Centres in Developed Countries

Although water, at least for basic needs, should be accessible to everyone, many families have trouble paying their water bill. Assessments of water affordability inform the design of water tariffs aimed at ensuring universal access to water. In order to carry out such assessments, managers must have instruments available that accurately reflect the state of water affordability. In this article, a critique is presented of one of the indicators traditionally used to measure water affordability and a proposal of an alternative way of measuring water affordability is put forward. The empirical analysis is applied to data from 301 communities in southern Spain.     

Technological characterization and survival of the exopolysaccharide-producing strain Lactobacillus delbrueckii subsp. lactis 193 and its bile-resistant derivative 193+ in simulated gastric and intestinal juices

The capacity of lactic acid bacteria to produce exopolysaccharides (EPS) conferring microorganisms a ropy phenotype could be an interesting feature from a technological point of view. Progressive adaptation to bile salts might render some lactobacilli able to overcome physiological gut barriers but could also modify functional properties of the strain, including the production of EPS. In this work some technological properties and the survival ability in simulated gastrointestinal conditions of Lactobacillus delbrueckii subsp. lactis 193, and Lb. delbrueckii subsp. lactis 193+, a strain with stable bile-resistant phenotype derived thereof, were characterized in milk in order to know whether the acquisition of resistance to bile could modify some characteristics of the microorganism. Both strains were able to grow and acidify milk similarly; however the production of ethanol increased at the expense of the aroma compound acetaldehyde in milk fermented by the strain 193+, with respect to milk fermented by the strain 193. Both microorganisms produced a heteropolysaccharide composed of glucose and galactose, and were able to increase the viscosity of fermented milks. In spite of the higher production yield of EPS by the bile-resistant strain 193+, it displayed a lower ability to increase viscosity than Lb. delbrueckii subsp. lactis 193. Milk increased survival in simulated gastric juice; the presence of bile improved adhesion to the intestinal cell line HT29-MTX in both strains. However, the acquisition of a stable resistance phenotype did not improve survival in simulated gastric and intestinal conditions or the adhesion to the intestinal cell line HT29-MTX. Thus, Lb. delbrueckii subsp. lactis 193 presents suitable technological properties for the manufacture of fermented dairy products; the acquisition of a stable bile-resistant phenotype modified some properties of the microorganism. This suggests that the possible use of bile-resistant derivative strains should be carefully evaluated in each specific application considering the influence that the acquisition of a stable bile-resistant phenotype could have in survival ability in gastric and intestinal conditions and in technological properties.     

HYDROGEN TRAIPB-NUUEAR MAGNETIC RESONANCE FOR INDUSTRIAL MOISTURE 8EN8MG

ABSTRACT

A procedure was developed based on a three-component physical model to simulate the drying characteristics of Laird lentils. In this model, the cotyledons were simplified as a homogeneous slab where moisture transfer was governed by a one-dimensional diffusion equation, and the hilum and seedcoat were considered as two parallel routes for moisture to escape from a seed. The simulation procedure was verified with the experimental data from thin-layer drying testing on samples of 19.0 to 24.5% initial moisture content at temperatures from 23 to 80°C and relative humidities from 5 to 70%. Using previously obtained information on the transport properties of the cotyledons, the seedcoat, and the hilum, the simulation followed the drying data closely over temperatures between 23 and 60°C.     

Integration between art and science in architectural design

The paper deals with a problem that has been crucial in teaching and practising architectural design since the XVIII century, when the separation between the Academies and the Polytechnics denied the integration between art and science in architectural design. The question becomes more crucial today with the demands arising from the energy saving, environmental awareness and sustainability achievements. An analysis is proposed for focusing the reasons of such a separation and some interventions are suggested in order to improve the efficiency of a design process that composes architectures by means of architectures.