Architecture Takes Time

Though condensed between the stages of design and completion, the conventional process of designing a building is time consuming, involving various stakeholders, planning processes and a wide team of consultants and contractors. What happens, though, if the time period of an architect's involvement is expanded? How might a more process-orientated approach shift the role of the architect? Tobias Armborst, Daniel D'Oca and Georgeen Theodore , principals of Interboro Partners in New York, describe how they have developed projects that have sought opportunities in expanding the timescale and remit of traditional practice.     

Metal hydride material requirements for automotive hydrogen storage systems

The United States Department of Energy (DOE) has published a progression of technical targets to be satisfied by on-board rechargeable hydrogen storage systems in light-duty vehicles. By combining simplified storage system and vehicle models with interpolated data from metal hydride databases, we obtain material-level requirements for metal hydrides that can be assembled into systems that satisfy the DOE targets for 2017. We assume minimal balance-of-plant components for systems with and without a hydrogen combustion loop for supplemental heating. Tank weight and volume are driven by the stringent requirements for refueling time. The resulting requirements suggest that, at least for this specific application, no current on-board rechargeable metal hydride satisfies these requirements.     

Foraging theory for autonomous vehicle speed choice

We consider the optimal control design of an abstract autonomous vehicle (AAV). The AAV searches an area for tasks that are detected with a probability that depends on vehicle speed, and each detected task can be processed or ignored. Both searching and processing are costly, but processing also returns rewards that quantify designer preferences. We generalize results from the analysis of animal foraging behavior to model the AAV. Then, using a performance metric common in behavioral ecology, we explicitly find the optimal speed and task processing choice policy for a version of the AAV problem. Finally, in simulation, we show how parameter estimation can be used to determine the optimal controller online when density of task types is unknown.     

Properties of single-walled carbon nanotube-based aerogels as a function of nanotube loading

Here, we present the synthesis and characterization of low-density single-walled carbon nanotube-based aerogels (SWNT-CA). Aerogels with varying nanotube loading (0–55 wt.%) and density (20–350 mg cm^?3) were fabricated and characterized by four-probe method, electron microscopy, Raman spectroscopy and nitrogen porosimetry. Several properties of the SWNT-CAs were highly dependent upon nanotube loading. At nanotube loadings of 55 wt.%, shrinkage of the aerogel monoliths during carbonization and drying was almost completely eliminated. Electrical conductivities are improved by an order of magnitude for the SWNT-CA (55 wt.% nanotubes) compared to those of foams without nanotubes. Surface areas as high as 184 m² g^?1 were achieved for SWNT-CAs with greater than 20 wt.% nanotube loading.     

Sorption of N-butane,propane, and ethane in ethylcellulose

The sorption of n-butane, propane, and ethane in ethylcellulose has been investigated between 0 and 200 mm Hg pressure over the temperature range from 30 to 70°C. Sorption isotherms of n-butane, propane, and ethane in ethylcellulose suggest that both Henry's law and the Langmuir forms of sorption, are operative. Sorption data were analyzed using the dual sorption model and sorption parameters determined. The sorption attributed to the Langmuir mode decreases as the temperature increases. This result indicates that the nonlinear Langmuir mode of sorption is more characteristic of the glassy state than sorption represented by the Henry's law mode. It was found that sorption attributed to the Henry's law and Langmuir modes decreases as the molecular size of gaseous hydrocarbon penetrants decrease. In this study, the molecular size of gaseous molecule decreased as the gases studied changed from n-butane to propane to ethane. A correlation of the Henry's law constants for the solution of n-butane, propane, and ethane in ethylcellulose with the Lennard-Jones force constants, ?/k at different temperatures was also determined. The temperature dependence of the Henry's law constants were correlated by a van't Hoff relationship and heats of sorption determined.     

Integrated behavior change techniques for problem drinkers in the community.

Evaluated the therapeutic potential of learning techniques in changing abusive drinking patterns and achieving moderation using 80 regularly employed drinkers with intact families, remaining self-esteem, but also alcohol-related problems. The following procedures were studied: videotaped self-confrontation of drunken behavior, aversion training for overconsumption, discrimination training for blood alcohol concentration, alternatives training, behavior counseling, and alcohol education. All the techniques were applied to Group 1 (n?=?23), the last 4 to Group 2 (n?=?19), alcohol education only to Group 3 (n?=?21), and the last 3 to Group 4 (n?=?17). Tests administered included the California Psychological Inventory, the Marlowe-Crowne Social Desirability Scale, and Rotter's Internal–External Locus of Control Scale. During the 1st yr of follow-up, significant decreases in alcohol intake were found for all groups, and the percentage of moderate drinkers changed from 0% to 62.5%. Significant differences between groups were not found. The effects on outcome of a large variance in pretreatment S characteristics such as alcohol intake, the amount of possible change in intake, the program's learning orientation, and blind follow-up are discussed as factors that may partially account for the lack of differential treatment effects. It is concluded that moderation is a more attainable and feasible goal for problem drinkers than for chronic alcoholics. (36 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)